Say the payout in chips, not just in money

"Ann - $135" is the answer to the arithmetic. The dealer's actual job at that moment
is working out that $135 is a black, a green and two reds, while four people watch
them do it.

The chip legend has known the denominations all along. It was only being used to read
chips *into* an amount -- counting a seat's stack -- and never to turn an amount back
into chips.

  Final Payouts
    Ann - $135
    1x$100, 1x$25, 2x$5

Largest first, which is greedy and so not optimal for an arbitrary set of values. Poker
chips are not arbitrary: every real set is canonical -- each denomination divides the
next, 1/5/25/100/500 -- and greedy is exactly optimal on those. A dealer who invents a
3-and-7 chip set still gets a valid answer, possibly one chip longer than it needed to
be, which is a fair trade for not solving a knapsack in a modal.

Two cases where saying nothing is the right answer, and one where it is not.

A table with no chip legend gets the amount on its own -- it has not told us its
denominations, so there is no advice to give. But a legend that exists and cannot reach
the amount does say so: "$3 no chip covers" when the smallest chip is $5. Half a dollar
in a dollar-chip game is the dealer's problem to solve and they can only solve it if
they are told, so it is never rounded away.

12 tests (244 total): the breakdown adds up to the amount across eight amounts, cent
chips make cent amounts exactly, a jumbled legend still pays largest first, the colour
comes along for a future caller, and the two no-advice cases are told apart from the
cannot-reach one.

Driven through a real all-in hand at four sizes: $135 reads "1x$100, 1x$25, 2x$5" and
a tournament-sized $1,350 reads "2x$500, 3x$100, 2x$25", fitting without spill down to
360px. With the legend emptied the line disappears and the payout stands alone.
Contrast clean, no console errors.

Co-Authored-By: Claude Opus 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_015bnp7xKUPFFSpwkYNFaPgb

.gitea/workflows/deploy.yml

@@ -0,0 +1,97 @@
+# .gitea/workflows/deploy.yml
+name: Build and Deploy
+
+on:
+  push:
+    branches: [ "master" ]
+  workflow_dispatch: {}
+
+concurrency:
+  group: deploy-${{ gitea.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build-deploy:
+    # Gitea's runner images are lean, so the toolchain is installed below rather
+    # than assumed. The glibc that libchess_engine.so links against comes from
+    # this image, not from the runner host — keep it matched to the prod server.
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Install toolchain
+        run: |
+          apt-get update
+          apt-get install -y --no-install-recommends \
+            cmake build-essential rsync openssh-client
+
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: '8.0.x'
+
+      - name: Restore
+        run: dotnet restore JoshHeaps.Net/JoshHeaps.Net.csproj
+
+      - name: Build native chess engine (libchess_engine.so)
+        run: |
+          cmake -S native/chess_engine -B native/chess_engine/build -DCMAKE_BUILD_TYPE=Release
+          cmake --build native/chess_engine/build
+          cp native/chess_engine/build/libchess_engine.so JoshHeaps.Net/Resources/
+
+      # Publishing the project rather than the solution keeps chess_engine.vcxproj
+      # (Windows-only MSBuild C++ targets) and the UiTests assemblies out of it.
+      - name: Publish
+        run: dotnet publish JoshHeaps.Net/JoshHeaps.Net.csproj -c Release -o ./publish
+
+      - name: Verify payload
+        run: |
+          set -euo pipefail
+          test -f publish/Resources/libchess_engine.so \
+            || { echo "libchess_engine.so missing from publish output"; exit 1; }
+          test -x publish/Resources/stockfish-ubuntu-x86-64-sse41-popcnt \
+            || { echo "stockfish is not executable"; exit 1; }
+
+      - name: Prepare SSH
+        env:
+          SSH_KEY:  ${{ secrets.SSH_KEY }}
+          SSH_HOST: ${{ secrets.SSH_HOST }}
+          SSH_PORT: ${{ secrets.SSH_PORT }}
+        run: |
+          set -euo pipefail
+          PORT="${SSH_PORT:-22}"
+          install -m 700 -d ~/.ssh
+          printf '%s\n' "$SSH_KEY" > ~/.ssh/deploy_key
+          chmod 600 ~/.ssh/deploy_key
+          ssh-keyscan -p "$PORT" "$SSH_HOST" >> ~/.ssh/known_hosts 2>/dev/null
+
+      # --exclude chess-data: never let --delete remove the learned-engine training
+      # data, which lives in the deploy dir unless ChessEngine__WeightsPath is set.
+      - name: Rsync to server
+        env:
+          SSH_HOST:   ${{ secrets.SSH_HOST }}
+          SSH_PORT:   ${{ secrets.SSH_PORT }}
+          SSH_USER:   ${{ secrets.SSH_USER }}
+          TARGET_DIR: ${{ secrets.TARGET_DIR }}
+        run: |
+          set -euo pipefail
+          PORT="${SSH_PORT:-22}"
+          rsync -az --delete --exclude 'chess-data' \
+            -e "ssh -p $PORT -i ~/.ssh/deploy_key -o StrictHostKeyChecking=yes" \
+            publish/ "$SSH_USER@$SSH_HOST:$TARGET_DIR/"
+
+      - name: Reload and restart service
+        env:
+          SSH_HOST:     ${{ secrets.SSH_HOST }}
+          SSH_PORT:     ${{ secrets.SSH_PORT }}
+          SSH_USER:     ${{ secrets.SSH_USER }}
+          SERVICE_NAME: ${{ secrets.SERVICE_NAME }}
+        run: |
+          set -euo pipefail
+          PORT="${SSH_PORT:-22}"
+          ssh -p "$PORT" -i ~/.ssh/deploy_key "$SSH_USER@$SSH_HOST" \
+            "sudo systemctl daemon-reload \
+             && sudo systemctl restart '$SERVICE_NAME' \
+             && systemctl --no-pager status '$SERVICE_NAME' --lines=0"

.github/workflows/deploy.yml

@@ -54,6 +54,12 @@ jobs:
           name: site-publish
           path: publish
 
+      # GitHub artifacts don't preserve the Unix executable bit, so Stockfish (the only file
+      # the app spawns as a subprocess) arrives non-executable. Restore 755 here; rsync -a then
+      # carries it to the server, where the service user can run it regardless of file owner.
+      - name: Restore Stockfish executable bit
+        run: chmod 755 publish/Resources/stockfish-ubuntu-x86-64-sse41-popcnt
+
       - name: Prepare SSH
         run: |
           install -m 700 -d ~/.ssh
@@ -63,7 +69,9 @@ jobs:
 
       - name: Rsync to server
         run: |
-          rsync -az --delete -e "ssh -p ${{ secrets.SSH_PORT || 22 }} -i ~/.ssh/id_rsa" \
+          # --exclude chess-data: never let --delete remove the learned-engine training
+          # data, which lives in the deploy dir unless ChessEngine__WeightsPath is set.
+          rsync -az --delete --exclude 'chess-data' -e "ssh -p ${{ secrets.SSH_PORT || 22 }} -i ~/.ssh/id_rsa" \
             publish/ ${{ secrets.SSH_USER }}@${{ secrets.SSH_HOST }}:${{ secrets.TARGET_DIR }}/
 
       - name: Reload and restart service

.github/workflows/holdem-tests.yml

@@ -0,0 +1,26 @@
+# Unit tests for the Texas Hold'em dealer's money logic.
+#
+# The betting engine, the side-pot calculator and the table state are plain script-tag
+# modules with no build step, so they run directly under Node's built-in test runner —
+# no package.json, no install step, nothing to keep up to date.
+
+name: Hold'em tests
+
+on:
+  pull_request:
+    branches: [ "master" ]
+  push:
+    branches: [ "master" ]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Setup Node
+      uses: actions/setup-node@v4
+      with:
+        node-version: 20
+    - name: Run Hold'em unit tests
+      run: node --test tests/holdem/*.test.js

.gitignore

@@ -3,6 +3,9 @@
 ##
 ## Get latest from https://github.com/github/gitignore/blob/master/VisualStudio.gitignore
 
+# Learned chess engine weights (runtime training output, not source)
+chess-data/
+
 # User-specific files
 *.rsuser
 *.suo

JoshHeaps.Net/Controllers/ChessController.cs

@@ -1,10 +1,9 @@
-using JoshHeaps.Net.Hubs;
+using JoshHeaps.Net.Hubs;
 using JoshHeaps.Net.Models;
 using JoshHeaps.Net.Services.Implementations;
 using JoshHeaps.Net.Services.Interfaces;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.SignalR;
-using System.Collections.Concurrent;
 
 namespace JoshHeaps.Net.Controllers;
 
@@ -15,58 +14,60 @@ public class ChessController(
     IBackgroundTaskQueue queue,
     IChessEngineFactory engineFactory,
     IComputerMoveOrchestrator orchestrator,
+    ILearnedWeightsStore weightsStore,
+    IGameStore gameStore,
+    ISelfPlayCoordinator selfPlay,
+    AutoTrainingSettings autoTraining,
     IHubContext<ChessHub> chessHub) : ControllerBase
 {
-    /// <summary>
-    /// Store of ongoing games.
-    /// </summary>
-    private static readonly ConcurrentDictionary<Guid, GameState> _games = [];
-    private static readonly ConcurrentDictionary<Guid, Task> _gameRemovalTasks = [];
-    private static readonly ConcurrentDictionary<Guid, CancellationTokenSource> _gameRemovalCancellationTokens = [];
-
     private static readonly TimeSpan _computerGameTimeout = TimeSpan.FromHours(1);
     private static readonly TimeSpan _multiplayerGameTimeout = TimeSpan.FromDays(1);
     private static readonly TimeSpan _gameCleanupTimeout = TimeSpan.FromMinutes(1);
-    private static readonly TimeSpan _selfPlayMoveDelay = TimeSpan.FromSeconds(1);
-    private static readonly TimeSpan _selfPlayResultTimeout = TimeSpan.FromSeconds(30);
 
     /// <summary>
     /// Create a new chess game and store it in-memory.
     /// </summary>
     [HttpGet("new")]
     [HttpGet("new/{difficulty}")]
-    public ActionResult CreateGame(int difficulty = 20)
+    public ActionResult CreateGame(int difficulty = 20, string color = "random")
     {
         var gameState = chessService.CreateNewGame();
-        _games[gameState.GameId] = gameState;
+        gameStore.Add(gameState);
 
         gameState.IsVsComputer = true;
         gameState.WhiteJoined = true;
         gameState.BlackJoined = true;
         Guid playerId = Guid.NewGuid();
         Guid computerId = Guid.NewGuid();
-        var isWhite = Random.Shared.Next(2) == 0;
+        var isWhite = color.ToLowerInvariant() switch
+        {
+            "white" => true,
+            "black" => false,
+            _ => Random.Shared.Next(2) == 0,
+        };
 
-        gameState.Computer = engineFactory.Create(difficulty);
+        var computer = engineFactory.Create(difficulty);
 
         if (isWhite)
         {
             gameState.WhitePlayerId = playerId;
             gameState.BlackPlayerId = computerId;
+            gameState.BlackComputer = computer;
         }
         else
         {
             gameState.WhitePlayerId = computerId;
             gameState.BlackPlayerId = playerId;
+            gameState.WhiteComputer = computer;
             queue.Queue(async () =>
             {
                 // Give user's browser time to connect to signalR and such.
                 await Task.Delay(TimeSpan.FromSeconds(1));
-                await orchestrator.PlayAsync(gameState, gameState.Computer!);
+                await orchestrator.PlayAsync(gameState);
             });
         }
 
-        ScheduleRemoveGame(gameState.GameId, _computerGameTimeout);
+        gameStore.ScheduleRemove(gameState.GameId, _computerGameTimeout);
 
         return Ok(new
         {
@@ -77,28 +78,52 @@ public class ChessController(
     }
 
     /// <summary>
-    /// Create a game the computer plays against itself and auto-play it move by move,
-    /// broadcasting each move so it can be watched on the spectator page.
+    /// Create a computer-vs-computer game and auto-play it move by move, broadcasting each
+    /// move so it can be watched on the spectator page. Each side's engine and skill can be
+    /// chosen independently; when the learned engine plays, the game also trains it.
     /// </summary>
     [HttpGet("watch/cpu")]
     [HttpGet("watch/cpu/{difficulty}")]
-    public ActionResult CreateSelfPlayGame(int difficulty = 4)
+    public ActionResult CreateSelfPlayGame(
+        int difficulty = 4,
+        string whiteEngine = "custom",
+        string blackEngine = "custom",
+        int? whiteSkill = null,
+        int? blackSkill = null)
     {
-        var gameState = chessService.CreateNewGame();
-        _games[gameState.GameId] = gameState;
+        var config = new SelfPlayConfig(
+            ParseEngineKind(whiteEngine), whiteSkill ?? difficulty,
+            ParseEngineKind(blackEngine), blackSkill ?? difficulty);
 
-        gameState.IsVsComputer = true;
-        gameState.IsComputerVsComputer = true;
-        gameState.WhiteJoined = true;
-        gameState.BlackJoined = true;
-        gameState.WhitePlayerId = Guid.NewGuid();
-        gameState.BlackPlayerId = Guid.NewGuid();
-        gameState.Computer = engineFactory.Create(difficulty);
+        var (gameId, _) = selfPlay.StartGame(config);
 
-        ScheduleRemoveGame(gameState.GameId, _computerGameTimeout);
-        StartSelfPlay(gameState);
+        return Ok(new { GameId = gameId });
+    }
 
-        return Ok(new { gameState.GameId });
+    private static ChessEngineKind ParseEngineKind(string value) => value.ToLowerInvariant() switch
+    {
+        "stockfish" => ChessEngineKind.Stockfish,
+        "customlearned" or "learned" => ChessEngineKind.CustomLearned,
+        _ => ChessEngineKind.Custom
+    };
+
+    /// <summary>
+    /// Current number of background auto-training games (and the allowed maximum). Auto-training
+    /// itself runs only outside Development; this reflects the target the service is keeping.
+    /// </summary>
+    [HttpGet("autotrain")]
+    public ActionResult GetAutoTrain() =>
+        Ok(new { count = autoTraining.GameCount, max = AutoTrainingSettings.MaxGames });
+
+    /// <summary>
+    /// Set how many auto-training games run concurrently (clamped to 0..max; 0 pauses training).
+    /// Takes effect live — the background service tops up or drains toward the new count.
+    /// </summary>
+    [HttpPost("autotrain")]
+    public ActionResult SetAutoTrain([FromQuery] int count)
+    {
+        autoTraining.GameCount = count;   // clamped inside the setter
+        return Ok(new { count = autoTraining.GameCount, max = AutoTrainingSettings.MaxGames });
     }
 
     /// <summary>
@@ -110,12 +135,12 @@ public class ChessController(
     public ActionResult JoinGame()
     {
         Console.WriteLine("joining game");
-        GameState? gameState = _games.Values.FirstOrDefault(g => g.IsOpen);
+        GameState? gameState = gameStore.All.FirstOrDefault(g => g.IsOpen);
 
         if (gameState == null)
         {
             gameState = chessService.CreateNewGame();
-            _games[gameState.GameId] = gameState;
+            gameStore.Add(gameState);
         }
 
         Guid playerId = Guid.NewGuid();
@@ -133,7 +158,7 @@ public class ChessController(
             isWhite = false;
         }
 
-        ScheduleRemoveGame(gameState.GameId, _multiplayerGameTimeout);
+        gameStore.ScheduleRemove(gameState.GameId, _multiplayerGameTimeout);
 
         return Ok(new
         {
@@ -149,7 +174,7 @@ public class ChessController(
     [HttpGet("active")]
     public ActionResult GetActiveGames()
     {
-        var activeGames = _games.Values
+        var activeGames = gameStore.All
             // In-progress games, plus finished computer-vs-computer games still in their result window.
             .Where(g => g.WhiteJoined && g.BlackJoined
                 && ((!g.IsCheckmate && !g.IsStalemate && !g.IsForfeited && !g.IsThreefoldRepetition) || g.IsComputerVsComputer))
@@ -158,6 +183,8 @@ public class ChessController(
                 g.GameId,
                 g.IsVsComputer,
                 g.IsComputerVsComputer,
+                WhiteEngine = g.WhiteEngineKind.ToString(),
+                BlackEngine = g.BlackEngineKind.ToString(),
                 CurrentPlayer = g.CurrentPlayer.ToString(),
                 MoveCount = g.MoveHistory.Count,
                 g.IsCheck
@@ -167,52 +194,46 @@ public class ChessController(
         return Ok(activeGames);
     }
 
+    /// <summary>
+    /// The learned engine's piece-square bonus table, for the weights-visualization page:
+    /// one 64-entry array per piece type (Pawn..King), white-relative (A1=0 .. H8=63).
+    /// </summary>
+    [HttpGet("weights")]
+    public ActionResult GetLearnedWeights()
+    {
+        var names = new[] { "Pawn", "Knight", "Bishop", "Rook", "Queen", "King" };
+        var featureNames = new[] { "Mobility N", "Mobility B", "Mobility R", "Mobility Q", "Passed", "Isolated", "Doubled", "King safety" };
+
+        var snapshot = weightsStore.Snapshot();
+
+        return Ok(new
+        {
+            mg = snapshot.Mg.Select((squares, i) => new { name = names[i], squares }),
+            eg = snapshot.Eg.Select((squares, i) => new { name = names[i], squares }),
+            features = snapshot.Features.Select((value, i) => new { name = featureNames[i], value })
+        });
+    }
+
     /// <summary>
     /// Get the state of an existing game by ID.
     /// </summary>
     [HttpGet("{gameId}")]
     public ActionResult GetGameState(Guid gameId)
     {
-        if (!_games.TryGetValue(gameId, out var gameState))
+        if (!gameStore.TryGet(gameId, out var gameState))
             return NotFound("Game not found");
 
-        var response = new
-        {
-            gameState.GameId,
-            CurrentPlayer = gameState.CurrentPlayer.ToString(),
-            gameState.IsCheck,
-            gameState.IsCheckmate,
-            gameState.IsStalemate,
-            gameState.IsThreefoldRepetition,
-            EnPassantTarget = gameState.EnPassantTarget?.ToString() ?? null,
-            gameState.WhiteCanCastleKingside,
-            gameState.WhiteCanCastleQueenside,
-            gameState.BlackCanCastleKingside,
-            gameState.BlackCanCastleQueenside,
-            Pieces = gameState.Pieces
-                .Where(p => p.Position.Row >= 0)
-                .Select(p => new {
-                    p.Id,
-                    p.Type,
-                    p.Color,
-                    p.Position.Row,
-                    p.Position.Col,
-                    p.HasMoved
-                }),
-            gameState.MoveHistory
-        };
-
-        return Ok(response);
+        return Ok(gameState.ToDto());
     }
 
     /// <summary>
-    /// Make a move in the specified game. 
+    /// Make a move in the specified game.
     /// The test passes a JSON body with a MoveDto.
     /// </summary>
     [HttpPost("move")]
-    public ActionResult MakeMove([FromBody] MoveDto moveDto)
+    public async Task<ActionResult> MakeMove([FromBody] MoveDto moveDto)
     {
-        if (!_games.TryGetValue(moveDto.GameId, out var gameState))
+        if (!gameStore.TryGet(moveDto.GameId, out var gameState))
             return NotFound("Game not found");
 
         // Check if player is authorized to move
@@ -239,16 +260,28 @@ public class ChessController(
         var isGameOver = result.IsCheckmate || result.IsStalemate || result.IsThreefoldRepetition;
 
         if (isGameOver)
-            ScheduleRemoveGame(gameState.GameId, _gameCleanupTimeout);
+            gameStore.ScheduleRemove(gameState.GameId, _gameCleanupTimeout);
         else if (gameState.IsVsComputer)
-            ScheduleRemoveGame(gameState.GameId, _computerGameTimeout);
+            gameStore.ScheduleRemove(gameState.GameId, _computerGameTimeout);
         else
-            ScheduleRemoveGame(gameState.GameId, _multiplayerGameTimeout);
+            gameStore.ScheduleRemove(gameState.GameId, _multiplayerGameTimeout);
 
-        if (!isGameOver && gameState.IsVsComputer && gameState.Computer is not null)
-            queue.Queue(() => orchestrator.PlayAsync(gameState, gameState.Computer!));
+        var state = gameState.ToDto();
 
-        return Ok(result);
+        // Broadcast the move (with the full resulting state) to everyone watching this
+        // game. The mover also receives this echo but drops it via the version guard,
+        // since it already rendered the same state from this response.
+        await chessHub.Clients.Group(gameState.GameId.ToString())
+            .SendAsync("ReceiveMoveUpdate", gameState.GameId.ToString(), moveDto, result, state);
+
+        var sideToMoveEngine = gameState.CurrentPlayer == PieceColor.White
+            ? gameState.WhiteComputer
+            : gameState.BlackComputer;
+
+        if (!isGameOver && gameState.IsVsComputer && sideToMoveEngine is not null)
+            queue.Queue(() => orchestrator.PlayAsync(gameState));
+
+        return Ok(new { result, state });
     }
 
     /// <summary>
@@ -258,7 +291,7 @@ public class ChessController(
     [HttpPost("forfeit")]
     public async Task<ActionResult> Forfeit([FromBody] ForfeitDto forfeit)
     {
-        if (!_games.TryGetValue(forfeit.GameId, out var gameState))
+        if (!gameStore.TryGet(forfeit.GameId, out var gameState))
             return NotFound("Game not found");
 
         if (gameState.IsCheckmate || gameState.IsStalemate || gameState.IsForfeited)
@@ -276,7 +309,7 @@ public class ChessController(
         await chessHub.Clients.Group(gameState.GameId.ToString())
             .SendAsync("ReceiveGameOver", gameState.GameId.ToString(), gameState.Winner.ToString(), "forfeit");
 
-        ScheduleRemoveGame(gameState.GameId, _gameCleanupTimeout);
+        gameStore.ScheduleRemove(gameState.GameId, _gameCleanupTimeout);
 
         return Ok();
     }
@@ -287,7 +320,7 @@ public class ChessController(
     [HttpGet("{gameId}/pgn")]
     public ActionResult GetPgn(Guid gameId)
     {
-        if (!_games.TryGetValue(gameId, out var gameState))
+        if (!gameStore.TryGet(gameId, out var gameState))
             return NotFound("Game not found");
 
         return Content(gameState.ToPgn(), "application/x-chess-pgn");
@@ -299,7 +332,7 @@ public class ChessController(
     [HttpGet("{gameId}/legalMoves/{pieceId}")]
     public ActionResult GetLegalMoves(Guid gameId, string pieceId)
     {
-        if (!_games.TryGetValue(gameId, out var gameState))
+        if (!gameStore.TryGet(gameId, out var gameState))
             return NotFound("Game not found");
 
         var moves = chessService.GetLegalMovesForPiece(gameState, pieceId);
@@ -313,7 +346,7 @@ public class ChessController(
     [HttpGet("{gameId}/legalMoves")]
     public ActionResult GetAllLegalMoves(Guid gameId)
     {
-        if (!_games.TryGetValue(gameId, out var gameState))
+        if (!gameStore.TryGet(gameId, out var gameState))
             return NotFound("Game not found");
 
         var allMoves = chessService.GetAllLegalMoves(gameState)
@@ -325,75 +358,4 @@ public class ChessController(
 
         return Ok(allMoves);
     }
-
-    /// <summary>
-    /// Drives a computer-vs-computer game: keeps asking the engine for the side-to-move's
-    /// move (which applies and broadcasts it) until the game ends or is removed.
-    /// </summary>
-    private void StartSelfPlay(GameState gameState)
-    {
-        queue.Queue(async () =>
-        {
-            // Give spectators a moment to join the SignalR group before the first move.
-            await Task.Delay(TimeSpan.FromSeconds(1));
-
-            while (_games.ContainsKey(gameState.GameId)
-                && !gameState.IsCheckmate
-                && !gameState.IsStalemate
-                && !gameState.IsThreefoldRepetition
-                && !gameState.IsForfeited)
-            {
-                try
-                {
-                    await orchestrator.PlayAsync(gameState, gameState.Computer!);
-                }
-                catch (Exception ex)
-                {
-                    Console.WriteLine($"Self-play game {gameState.GameId} stopped: {ex.Message}");
-                    break;
-                }
-
-                await Task.Delay(_selfPlayMoveDelay);
-            }
-
-            // Leave the finished game in place briefly so spectators can see the result.
-            if (_games.ContainsKey(gameState.GameId))
-                ScheduleRemoveGame(gameState.GameId, _selfPlayResultTimeout);
-        });
-    }
-
-    private static void ScheduleRemoveGame(Guid id, TimeSpan delay)
-    {
-        if (_gameRemovalCancellationTokens.TryRemove(id, out var oldCts))
-        {
-            oldCts.Cancel();
-            oldCts.Dispose();
-        }
-
-        var cts = new CancellationTokenSource();
-        _gameRemovalCancellationTokens[id] = cts;
-
-        _gameRemovalTasks[id] = Task.Run(async () =>
-        {
-            try
-            {
-                await Task.Delay(delay, cts.Token);
-
-                if (_games.TryGetValue(id, out var game) && game.Computer is not null)
-                    await game.Computer.DisposeAsync();
-
-                _games.Remove(id, out _);
-            }
-            catch (OperationCanceledException) { }
-            finally
-            {
-                if (_gameRemovalCancellationTokens.TryGetValue(id, out var currentCts) && currentCts == cts)
-                {
-                    _gameRemovalCancellationTokens.TryRemove(id, out _);
-                }
-
-                cts.Dispose();
-            }
-        });
-    }
 }

JoshHeaps.Net/Hubs/ChessHub.cs

@@ -1,5 +1,4 @@
-using JoshHeaps.Net.Models;
-using Microsoft.AspNetCore.SignalR;
+using Microsoft.AspNetCore.SignalR;
 
 namespace JoshHeaps.Net.Hubs;
 
@@ -11,11 +10,6 @@ public class ChessHub : Hub
         await Groups.AddToGroupAsync(Context.ConnectionId, gameId);
     }
 
-    public async Task MoveMade(string gameId, MoveDto moveDto, MoveResultDto moveResult)
-    {
-        await Clients.OthersInGroup(gameId).SendAsync("ReceiveMoveUpdate", gameId, moveDto, moveResult);
-    }
-
     public async Task LeaveWebsocketGroup(string gameId)
     {
         Console.WriteLine($"❌ Leaving group {gameId}");

JoshHeaps.Net/Models/GameState.cs

@@ -1,4 +1,5 @@
-using JoshHeaps.Net.Services.Interfaces;
+using JoshHeaps.Net.Services.Implementations;
+using JoshHeaps.Net.Services.Interfaces;
 
 namespace JoshHeaps.Net.Models;
 
@@ -59,7 +60,20 @@ public class GameState
     public bool IsVsComputer { get; set; } = false;
     public bool IsComputerVsComputer { get; set; } = false;
 
-    public IChessEngine? Computer { get; set; }
+    // The engine playing each side (null for a human). In a human-vs-computer game only the
+    // computer's side is set; the orchestrator picks the engine for whoever is to move.
+    public IChessEngine? WhiteComputer { get; set; }
+    public IChessEngine? BlackComputer { get; set; }
+
+    // Which engine implementation each side uses — lets game-over handling know which side(s)
+    // are the learning engine, and lets spectators see who is playing.
+    public ChessEngineKind WhiteEngineKind { get; set; }
+    public ChessEngineKind BlackEngineKind { get; set; }
+
+    // Native per-game training accumulator (nint.Zero when this game isn't training the
+    // learned engine). The engine records each played position into it and applies the
+    // result on game over.
+    public nint Trainer { get; set; }
 
     // optional: convenience
     public bool IsOpen => !WhiteJoined || !BlackJoined;

JoshHeaps.Net/Models/GameStateDto.cs

@@ -0,0 +1,61 @@
+using System.Linq;
+
+namespace JoshHeaps.Net.Models;
+
+/// <summary>
+/// A single piece as sent to the client. Captured pieces keep their original
+/// type and color; their position is meaningless and omitted.
+/// </summary>
+public record ChessPieceDto(string Id, PieceType Type, PieceColor Color, int Row, int Col, bool HasMoved);
+
+/// <summary>
+/// The full board state pushed to clients. The same shape is returned by the
+/// state endpoint, the move endpoint, and every SignalR move broadcast, so the
+/// client always renders from one authoritative payload instead of re-fetching.
+/// </summary>
+public record GameStateDto(
+    Guid GameId,
+    string CurrentPlayer,
+    bool IsCheck,
+    bool IsCheckmate,
+    bool IsStalemate,
+    bool IsThreefoldRepetition,
+    string? EnPassantTarget,
+    bool WhiteCanCastleKingside,
+    bool WhiteCanCastleQueenside,
+    bool BlackCanCastleKingside,
+    bool BlackCanCastleQueenside,
+    IReadOnlyList<ChessPieceDto> Pieces,
+    IReadOnlyList<ChessPieceDto> CapturedPieces,
+    IReadOnlyList<string> MoveHistory,
+    // Moves in standard algebraic notation, for the move-list panel.
+    IReadOnlyList<string> SanHistory,
+    // Monotonic ply counter the client uses to drop stale or echoed updates.
+    int Version);
+
+public static class GameStateMapper
+{
+    public static GameStateDto ToDto(this GameState gameState) => new(
+        gameState.GameId,
+        gameState.CurrentPlayer.ToString(),
+        gameState.IsCheck,
+        gameState.IsCheckmate,
+        gameState.IsStalemate,
+        gameState.IsThreefoldRepetition,
+        gameState.EnPassantTarget?.ToString(),
+        gameState.WhiteCanCastleKingside,
+        gameState.WhiteCanCastleQueenside,
+        gameState.BlackCanCastleKingside,
+        gameState.BlackCanCastleQueenside,
+        gameState.Pieces
+            .Where(p => p.Position.Row >= 0)
+            .Select(p => new ChessPieceDto(p.Id, p.Type, p.Color, p.Position.Row, p.Position.Col, p.HasMoved))
+            .ToList(),
+        gameState.Pieces
+            .Where(p => p.Position.Row < 0)
+            .Select(p => new ChessPieceDto(p.Id, p.Type, p.Color, p.Position.Row, p.Position.Col, p.HasMoved))
+            .ToList(),
+        gameState.MoveHistory,
+        gameState.SanHistory,
+        gameState.MoveHistory.Count);
+}

JoshHeaps.Net/Models/LearnedWeightsSnapshot.cs

@@ -0,0 +1,9 @@
+namespace JoshHeaps.Net.Models;
+
+/// <summary>
+/// A copy of the learned engine's weights for display: midgame and endgame piece-square
+/// tables (one 64-entry array per piece, in canonical Pawn..King order, white-relative
+/// A1=0..H8=63) plus the feature weights (mobility N/B/R/Q, passed, isolated, doubled,
+/// king safety).
+/// </summary>
+public sealed record LearnedWeightsSnapshot(int[][] Mg, int[][] Eg, int[] Features);

JoshHeaps.Net/Pages/Casino.cshtml

@@ -0,0 +1,58 @@
+@page
+@model JoshHeaps.Net.Pages.CasinoModel
+@{
+    ViewData["Title"] = "Casino Games";
+    Layout = "_Layout";
+}
+
+<div class="casino-container">
+    <h1 class="casino-header">Casino Games</h1>
+    <p class="casino-subtitle">Tools for running table games without doing the math yourself</p>
+
+    <div class="games-grid">
+        <a href="/casino/texasholdem" class="game-card">
+            <div class="game-icon">🃏</div>
+            <div class="game-title">Texas Hold'em</div>
+            <div class="game-description">
+                A dealer's assistant: seat players around the table, track blinds, chips and
+                all-ins, then split main and side pots automatically.
+            </div>
+        </a>
+
+        <a href="/casino/texasholdem/quicksplit" class="game-card">
+            <div class="game-icon">➗</div>
+            <div class="game-title">Quick Split</div>
+            <div class="game-description">
+                Chop a pot in seconds on your phone — no table setup, just the amount,
+                how many players are splitting it, and the smallest chip in play.
+            </div>
+        </a>
+
+        <div class="game-card disabled">
+            <div class="game-icon">🎲</div>
+            <div class="game-title">Craps</div>
+            <div class="game-description">Payout calculator for the table.</div>
+            <div class="coming-soon">Coming soon...</div>
+        </div>
+
+        <div class="game-card disabled">
+            <div class="game-icon">🎡</div>
+            <div class="game-title">Roulette</div>
+            <div class="game-description">Bet tracking and payout reference.</div>
+            <div class="coming-soon">Coming soon...</div>
+        </div>
+
+        <div class="game-card disabled">
+            <div class="game-icon">🂡</div>
+            <div class="game-title">Blackjack</div>
+            <div class="game-description">Multi-hand dealer tracker.</div>
+            <div class="coming-soon">Coming soon...</div>
+        </div>
+    </div>
+
+    <a href="/" class="home-button">← Back to Home</a>
+</div>
+
+@section Styles {
+    <link href="/css/casino/page.css?v=@ViewData["cssVersion"]" rel="stylesheet" type="text/css" />
+}

JoshHeaps.Net/Pages/Casino.cshtml.cs

@@ -0,0 +1,11 @@
+using Microsoft.AspNetCore.Mvc.RazorPages;
+
+namespace JoshHeaps.Net.Pages
+{
+    public class CasinoModel : PageModel
+    {
+        public void OnGet()
+        {
+        }
+    }
+}

JoshHeaps.Net/Pages/Casino/TexasHoldem.cshtml

@@ -0,0 +1,464 @@
+@page
+@model JoshHeaps.Net.Pages.Casino.TexasHoldemModel
+@{
+    ViewData["Title"] = "Texas Hold'em Dealer";
+    Layout = "_Layout";
+}
+
+<div id="holdemApp">
+    <header id="holdemHeader">
+        <div id="holdemHeaderLeft">
+            <h1>Texas Hold'em Dealer</h1>
+            <p class="holdemSubtitle">Seat your players, track the action, split the pot.</p>
+            <span id="handCounterBadge" class="handCounterBadge">Hand #1</span>
+        </div>
+        <div id="holdemHeaderActions">
+            <a href="/casino/texasholdem/quicksplit" class="holdemBtn" title="Chop a pot without setting up a table">Quick Split</a>
+            <button id="nextHandBtn" class="holdemBtn" title="Move the button, small blind and big blind to the next occupied seat">Next Hand ⟳</button>
+            <button id="resolvePotBtn" class="holdemBtn holdemBtnAccent">Resolve Pot</button>
+            <button id="resetTableBtn" class="holdemBtn holdemBtnDanger">Reset Table</button>
+            <a href="/casino" class="holdemBtn holdemBtnGhost">← Casino</a>
+        </div>
+    </header>
+
+    <div id="holdemLayout">
+        <section id="tableSection">
+            <div id="pokerTableWrap">
+                <div id="pokerTable">
+                    <div id="tableWatermark" aria-hidden="true">Texas Hold'em</div>
+                    <div id="potBadge">
+                        <span id="potBadgeLabel">Pot</span>
+                        <span id="potBadgeAmount">$0</span>
+                    </div>
+                </div>
+                <div id="betsLayer" aria-hidden="true"></div>
+                <div id="seatsLayer"></div>
+            </div>
+            <p id="tableHint" class="tableHint"></p>
+            <p class="tableHintActions">
+                <button type="button" id="openRulingsBtn" class="linkBtn">Common rulings</button>
+            </p>
+        </section>
+
+        <aside id="holdemSidebar">
+            <section id="seatEditorPanel" class="sidebarPanel seatEditorPanel">
+                <div class="seatSheetGrip" aria-hidden="true"></div>
+                <div class="seatEditorHeader">
+                    <h2 id="seatEditorTitle">Select a seat</h2>
+                    <button id="closeSeatEditorBtn" class="seatSheetClose" aria-label="Done editing this seat">Done</button>
+                </div>
+                <div id="seatEditorBody">
+                    <p class="fieldHint">Click a seat at the table to edit their name, cards, chips and anything else.</p>
+                </div>
+            </section>
+
+            <details class="sidebarPanel" open>
+                <summary>Table Setup</summary>
+                <div class="panelBody">
+                    <label class="fieldRow">
+                        <span>Seats at table</span>
+                        <input type="number" id="seatCountInput" min="2" max="24" value="10" />
+                    </label>
+                    <label class="fieldRow">
+                        <span>Blinds move</span>
+                        <select id="directionSelect">
+                            <option value="clockwise" selected>Clockwise</option>
+                            <option value="counterclockwise">Counterclockwise</option>
+                        </select>
+                    </label>
+                    <label class="fieldRow">
+                        <span>Dedicated dealer (not a seat)</span>
+                        <input type="checkbox" id="dedicatedDealerToggle" />
+                    </label>
+                    <p class="fieldHint">Turn this on if a person outside the game deals — no seat shows the dealer button, but blinds still rotate automatically each hand.</p>
+                    <div class="blindsRow">
+                        <label class="fieldRow">
+                            <span>Small blind</span>
+                            <input type="number" id="smallBlindInput" min="0" step="0.5" />
+                        </label>
+                        <label class="fieldRow">
+                            <span>Big blind</span>
+                            <input type="number" id="bigBlindInput" min="0" step="0.5" />
+                        </label>
+                    </div>
+                    <label class="fieldRow">
+                        <span>Starting stack ($)</span>
+                        <input type="number" id="defaultStackInput" min="0" step="1" placeholder="e.g. 200" />
+                    </label>
+                    <p class="fieldHint">Blinds post themselves each hand. Seats without their own stack start here.</p>
+
+                    <details class="subPanel">
+                        <summary>Without live betting</summary>
+                        <div class="subPanelBody">
+                            <label class="fieldRow">
+                                <span>Base pot amount ($)</span>
+                                <input type="number" id="basePotInput" min="0" step="1" placeholder="e.g. 500" />
+                            </label>
+                            <p class="fieldHint">For tracking a hand by hand instead of tapping the action: everyone is assumed to have put in this much, unless their seat says otherwise.</p>
+                        </div>
+                    </details>
+                </div>
+            </details>
+
+            <details class="sidebarPanel">
+                <summary>Session</summary>
+                <div class="panelBody">
+                    <h3 class="panelSubhead">Standings</h3>
+                    <div class="standingsTableWrap">
+                        <div id="standingsTable">
+                            <div class="standingsRow standingsHeader">
+                                <span>Player</span>
+                                <span class="standingsInHead">In</span>
+                                <span class="standingsWonHead">Won</span>
+                                <span>Net</span>
+                                <span title="Chips in front of them, less the cash they handed over">Cash out</span>
+                            </div>
+                            <div id="standingsList"></div>
+                        </div>
+                    </div>
+                    <p id="standingsEmptyHint" class="fieldHint">Everyone who has bought in shows up here, with what they'd be owed if the night ended now.</p>
+
+                    <div id="bankReconcile" class="bankReconcile" hidden>
+                        <div class="bankReconcileRow">
+                            <span>Cash taken</span>
+                            <span id="bankCashIn"></span>
+                        </div>
+                        <div class="bankReconcileRow">
+                            <span>Chips in play</span>
+                            <span id="bankChipsInPlay"></span>
+                        </div>
+                        <p id="bankReconcileVerdict" class="bankReconcileVerdict"></p>
+                    </div>
+
+                    <div id="settleUp" hidden>
+                        <h3 class="panelSubhead">Settle up</h3>
+                        <ul id="settleUpList" class="settleUpList"></ul>
+                        <p id="settleUpNote" class="fieldHint"></p>
+                    </div>
+
+                    <h3 class="panelSubhead">Hands</h3>
+                    <div id="handHistoryList"></div>
+                    <p id="handHistoryEmptyHint" class="fieldHint">Resolved pots are logged here, in case a chip count is disputed later.</p>
+
+                    <div class="handHistoryActions">
+                        <button id="exportHistoryBtn" class="holdemBtn holdemBtnSmall">Export CSV</button>
+                        <button id="clearHistoryBtn" class="holdemBtn holdemBtnSmall holdemBtnDanger">Clear history</button>
+                    </div>
+                </div>
+            </details>
+
+            <details class="sidebarPanel">
+                <summary>Chip Legend</summary>
+                <div class="panelBody">
+                    <div id="chipLegendList"></div>
+                    <button id="addChipColorBtn" class="holdemBtn holdemBtnSmall">+ Add chip color</button>
+                    <p class="fieldHint">Give each chip color a value, then count chips on a seat instead of typing a total.</p>
+                </div>
+            </details>
+
+            <details class="sidebarPanel">
+                <summary>Table Notes</summary>
+                <div class="panelBody">
+                    <textarea id="tableNotes" rows="4" aria-label="Table notes" placeholder="Anything else worth tracking — side bets, IOUs, running totals..."></textarea>
+                </div>
+            </details>
+        </aside>
+    </div>
+</div>
+
+<template id="seatTemplate">
+    <div class="seat" draggable="true">
+        <div class="seatChairNumber"></div>
+        <button class="dealerChip" type="button" title="Make this seat the dealer button">D</button>
+        <span class="blindBadge sbBadge">SB</span>
+        <span class="blindBadge bbBadge">BB</span>
+        <div class="seatPuckName"></div>
+        <div class="seatPuckCards"></div>
+        <div class="seatPuckTotal"></div>
+        <div class="seatPuckStack"></div>
+    </div>
+</template>
+
+<template id="seatEditorTemplate">
+    <div class="seatEditorForm">
+        <label class="fieldRow">
+            <span>Name</span>
+            <input type="text" class="seatNameInput" placeholder="Seat" maxlength="24" />
+        </label>
+        <div class="seatCardToggles">
+            <label class="inHandToggle" title="This seat is playing the current hand">
+                <input type="checkbox" class="inHandCheckbox" />
+                <span>In hand</span>
+            </label>
+            <label class="foldToggle" title="Folded">
+                <input type="checkbox" class="foldCheckbox" />
+                <span>Fold</span>
+            </label>
+        </div>
+        <div class="seatCards">
+            <button type="button" class="cardSlot card1Slot" aria-label="Choose first card"></button>
+            <button type="button" class="cardSlot card2Slot" aria-label="Choose second card"></button>
+        </div>
+        <label class="fieldRow stackRow">
+            <span>Stack</span>
+            <input type="number" class="stackInput" min="0" step="1" placeholder="table default" />
+        </label>
+        <div class="seatBuyIns" hidden></div>
+        <div class="seatContribution">
+            <div class="chipCounts"></div>
+            <label class="fieldRow amountOverrideRow">
+                <span>$ amount</span>
+                <input type="number" class="amountOverrideInput" min="0" step="1" placeholder="auto" />
+            </label>
+            <div class="seatTotal">Total: <span class="seatTotalAmount">$0</span></div>
+        </div>
+        <div class="customFields"></div>
+        <button class="holdemBtn holdemBtnSmall addFieldBtn">+ field</button>
+    </div>
+</template>
+
+<template id="chipLegendRowTemplate">
+    <div class="chipLegendRow">
+        <input type="color" class="chipColorInput" aria-label="Chip colour" />
+        <input type="number" class="chipValueInput" min="0" step="0.01" placeholder="value" aria-label="Chip value" />
+        <button class="holdemBtn holdemBtnSmall holdemBtnDanger removeChipColorBtn">×</button>
+    </div>
+</template>
+
+<template id="chipCountTemplate">
+    <label class="chipCountRow">
+        <span class="chipSwatch"></span>
+        <input type="number" class="chipCountInput" min="0" step="1" value="0" />
+    </label>
+</template>
+
+<template id="customFieldTemplate">
+    <div class="customFieldRow">
+        <input type="text" class="customFieldLabel" placeholder="Label" maxlength="20" />
+        <input type="text" class="customFieldValue" placeholder="Value" maxlength="40" />
+        <button class="holdemBtn holdemBtnSmall holdemBtnDanger removeFieldBtn">×</button>
+    </div>
+</template>
+
+<template id="standingsRowTemplate">
+    <div class="standingsRow">
+        <span class="standingsName"></span>
+        <span class="standingsIn"></span>
+        <span class="standingsWon"></span>
+        <span class="standingsNet"></span>
+        <span class="standingsCashOut"></span>
+    </div>
+</template>
+
+<template id="handHistoryRowTemplate">
+    <div class="handHistoryRow">
+        <div class="handHistoryRowHeader">
+            <span class="handHistoryHandNumber"></span>
+            <span class="handHistoryPot"></span>
+            <span class="handHistoryTime"></span>
+        </div>
+        <div class="handHistoryPayouts"></div>
+    </div>
+</template>
+
+<div id="addChipsOverlay" hidden>
+    <div id="addChipsSheet" role="dialog" aria-labelledby="addChipsTitle">
+        <div class="seatSheetGrip" aria-hidden="true"></div>
+        <div class="addChipsHeader">
+            <h2 id="addChipsTitle"></h2>
+            <span id="addChipsSubtitle"></span>
+        </div>
+        <div id="addChipsQuick"></div>
+        <div class="addChipsEntry">
+            <span class="addChipsCurrency">$</span>
+            <input type="text" id="addChipsInput" inputmode="decimal" autocomplete="off" aria-label="Amount to add" />
+        </div>
+        <div class="addChipsActions">
+            <button id="addChipsConfirmBtn" class="holdemBtn holdemBtnAccent" type="button">Add to stack</button>
+            <button id="addChipsCancelBtn" data-modal-close class="holdemBtn holdemBtnGhost" type="button">Cancel</button>
+        </div>
+    </div>
+</div>
+
+<div id="rulingsOverlay" hidden>
+    <div id="rulingsSheet" role="dialog" aria-labelledby="rulingsTitle">
+        <div class="seatSheetGrip" aria-hidden="true"></div>
+        <div class="rulingsHeader">
+            <h2 id="rulingsTitle">Common rulings</h2>
+            <button id="closeRulingsBtn" data-modal-close class="holdemBtn holdemBtnSmall holdemBtnGhost" type="button">Done</button>
+        </div>
+
+        <p class="rulingsIntro">
+            The conventions most rooms follow, for the calls that come up mid-hand.
+            Your house rules always win — and settle a dispute before the next hand,
+            not during it.
+        </p>
+
+        <section class="ruling">
+            <h3>Redeal it — misdeal</h3>
+            <ul>
+                <li>The first card goes to the wrong seat.</li>
+                <li>A seat entitled to a hand gets dealt out, or a seat that isn't entitled gets dealt in.</li>
+                <li>Two or more boxed cards turn up on the initial deal.</li>
+                <li>Either of the first two cards is exposed by dealer error.</li>
+            </ul>
+        </section>
+
+        <section class="ruling">
+            <h3>A board card turned too early</h3>
+            <p>
+                If the fourth board card gets turned before the betting round is finished,
+                that card is out of play for the round. Finish the betting, then burn and
+                turn what would have been the fifth card in the fourth card's place.
+            </p>
+        </section>
+
+        <section class="ruling">
+            <h3>Acting out of turn</h3>
+            <p>
+                A one-off is usually just backed up if no one has acted behind them.
+                Doing it repeatedly is what earns a penalty.
+            </p>
+        </section>
+
+        <section class="ruling">
+            <h3>A short all-in doesn't reopen the betting</h3>
+            <p>
+                Somebody shoving in less than a full raise — say $3 more when the last
+                raise was $8 — does not give the players behind them another go. Anyone
+                who has already acted owes the difference or folds; they don't get to
+                raise again because a short stack happened to land between them.
+            </p>
+            <p>
+                A player who hadn't acted yet keeps full rights and may still raise, and
+                the minimum raise stays measured off the last <em>full</em> raise, not
+                off the short one. The action bar follows this for you.
+            </p>
+        </section>
+
+        <section class="ruling">
+            <h3>Chips nobody called come back</h3>
+            <p>
+                Bet more than anyone was able to call and the excess is returned to you
+                before the showdown — it was never contested, so it isn't part of the
+                pot. The pot breakdown shows it as "uncalled" rather than pretending it's
+                a side pot you could win.
+            </p>
+        </section>
+
+        <section class="ruling">
+            <h3>One big chip, nothing said</h3>
+            <p>
+                The most common argument at a home table. A player facing a bet who
+                pushes out a single oversized chip without saying anything has
+                <em>called</em> — not raised, however big the chip is. To raise with one
+                chip you have to say "raise" before it lands; say it without an amount
+                and the raise is the most that chip allows.
+            </p>
+            <p>
+                Facing no bet, the same silent chip is a bet of the whole chip. And a
+                clear verbal declaration in turn is binding either way — if words and
+                chips disagree, whichever came first is the action.
+            </p>
+        </section>
+
+        <section class="ruling">
+            <h3>A raise has to be a full raise</h3>
+            <p>
+                At least as much again as the last raise, or the big blind if there
+                hasn't been one. Anything between a call and that minimum isn't a raise
+                a player can make — it's a call, unless they're putting their last chips
+                in. The raise pad says so if you type one, and won't stop you: your
+                ruling beats the arithmetic.
+            </p>
+        </section>
+
+        <section class="ruling">
+            <h3>The odd chip in a split pot</h3>
+            <p>
+                When a chopped pot won't divide evenly, the odd chip goes to the first
+                player left of the button, not to whoever the dealer happened to tick
+                first. Pot payouts here order the winners that way, so the leftover lands
+                on the right seat every time.
+            </p>
+        </section>
+
+        <p class="rulingsSource">
+            Follows the Tournament Directors Association rules, which most rooms and
+            home games take their lead from.
+        </p>
+    </div>
+</div>
+
+<div id="seatMenuOverlay" hidden>
+    <div id="seatMenuSheet" role="dialog" aria-labelledby="seatMenuTitle">
+        <div class="seatSheetGrip" aria-hidden="true"></div>
+        <div class="seatMenuHeader">
+            <h2 id="seatMenuTitle"></h2>
+            <span id="seatMenuSubtitle"></span>
+        </div>
+        <div id="seatMenuActions"></div>
+        <button id="seatMenuCancelBtn" data-modal-close class="holdemBtn holdemBtnGhost" type="button">Cancel</button>
+    </div>
+</div>
+
+<div id="cardPickerOverlay" hidden>
+    <div id="cardPickerSheet" role="dialog" aria-labelledby="cardPickerTitle">
+        <div class="seatSheetGrip" aria-hidden="true"></div>
+        <div class="cardPickerHeader">
+            <h2 id="cardPickerTitle"></h2>
+            <button id="cardPickerClearBtn" class="holdemBtn holdemBtnSmall" type="button">Clear</button>
+            <button id="cardPickerCloseBtn" data-modal-close class="holdemBtn holdemBtnSmall holdemBtnGhost" type="button">Done</button>
+        </div>
+        <div id="cardPickerSlots"></div>
+        <div id="cardPickerGrid"></div>
+    </div>
+</div>
+
+<div id="actionBar" aria-live="polite" hidden></div>
+
+<div id="toastHost" aria-live="polite"></div>
+
+<div id="confirmOverlay" hidden>
+    <div id="confirmModal" role="alertdialog" aria-labelledby="confirmTitle" aria-describedby="confirmMessage" tabindex="-1">
+        <h2 id="confirmTitle"></h2>
+        <p id="confirmMessage"></p>
+        <div class="confirmActions">
+            <button id="confirmCancelBtn" data-modal-close class="holdemBtn holdemBtnGhost" type="button">Cancel</button>
+            <button id="confirmAcceptBtn" class="holdemBtn holdemBtnDanger" type="button">Confirm</button>
+        </div>
+    </div>
+</div>
+
+<div id="potWizardOverlay" hidden>
+    <div id="potWizardModal" role="dialog" aria-labelledby="potWizardTitle">
+        <div class="potWizardHeader">
+            <h2 id="potWizardTitle">Resolve the Pot</h2>
+            <button id="closePotWizardBtn" data-modal-close class="holdemBtn holdemBtnGhost">✕</button>
+        </div>
+        <div id="potWizardBody"></div>
+    </div>
+</div>
+
+@section Styles {
+    <link href="/css/casino/holdem.css?v=@ViewData["cssVersion"]" rel="stylesheet" type="text/css" />
+}
+
+@section Scripts {
+    <script src="~/js/casino/holdem/money.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/feedback.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/potCalculator.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/state.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/settleUp.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/render.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/cardPicker.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/seatMenu.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/addChips.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/betting.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/actionBar.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/shortcuts.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/potWizard.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/handHistoryExport.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/modal.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/main.js?v=@ViewData["cssVersion"]"></script>
+}

JoshHeaps.Net/Pages/Casino/TexasHoldem.cshtml.cs

@@ -0,0 +1,11 @@
+using Microsoft.AspNetCore.Mvc.RazorPages;
+
+namespace JoshHeaps.Net.Pages.Casino
+{
+    public class TexasHoldemModel : PageModel
+    {
+        public void OnGet()
+        {
+        }
+    }
+}

JoshHeaps.Net/Pages/Casino/TexasHoldem/QuickSplit.cshtml

@@ -0,0 +1,95 @@
+@page
+@model JoshHeaps.Net.Pages.Casino.TexasHoldem.QuickSplitModel
+@{
+    ViewData["Title"] = "Quick Split";
+    Layout = "_Layout";
+}
+
+<div id="splitApp">
+    <header id="splitHeader">
+        <h1>Quick Split</h1>
+        <p class="splitSubtitle">Chop a pot without setting up a table.</p>
+    </header>
+
+    <div id="modeToggle" class="chipRow" role="group" aria-label="How the money went in">
+        <button type="button" id="modeEvenBtn" class="choiceChip selected">Everyone matched</button>
+        <button type="button" id="modeUnevenBtn" class="choiceChip">Someone's all-in</button>
+    </div>
+
+    <div id="splitResult" aria-live="polite">
+        <div id="splitResultLabel">Each player gets</div>
+        <div id="splitResultAmount">$0.00</div>
+        <div id="splitOddNote" hidden></div>
+        <div id="splitDustNote" hidden></div>
+    </div>
+
+    <div id="unevenResult" hidden aria-live="polite">
+        <div id="unevenPots"></div>
+        <p id="unevenEmpty" class="unevenEmpty">Enter what each player put in.</p>
+    </div>
+
+    <section class="splitField unevenOnly" hidden>
+        <span class="splitLabel">What each player put in</span>
+        <div id="unevenRows"></div>
+        <button type="button" id="addPlayerBtn" class="splitBtn splitBtnGhost">+ Add player</button>
+    </section>
+
+    <section class="splitField evenOnly">
+        <label for="potInput" class="splitLabel">Pot</label>
+        <div class="potInputWrap">
+            <span class="potCurrency">$</span>
+            <input type="text" id="potInput" inputmode="decimal" autocomplete="off"
+                   placeholder="0" aria-label="Pot amount" />
+            <button type="button" id="clearPotBtn" class="clearPotBtn" aria-label="Clear pot amount" hidden>✕</button>
+        </div>
+    </section>
+
+    <section class="splitField evenOnly">
+        <span class="splitLabel" id="waysLabel">Split between</span>
+        <div id="waysChoices" class="chipRow" role="group" aria-labelledby="waysLabel"></div>
+    </section>
+
+    <section class="splitField evenOnly">
+        <span class="splitLabel" id="chipLabel">Smallest chip in play</span>
+        <div id="chipChoices" class="chipRow" role="group" aria-labelledby="chipLabel"></div>
+    </section>
+
+    <div id="splitActions">
+        <button type="button" id="resetSplitBtn" class="splitBtn splitBtnGhost">Clear</button>
+        <a href="/casino/texasholdem" class="splitBtn splitBtnGhost">Full dealer table →</a>
+    </div>
+
+    <p class="splitFootnote evenOnly">
+        If somebody was all-in for less than the others, switch to
+        <strong>Someone's all-in</strong> above.
+    </p>
+
+    <p class="splitFootnote unevenOnly" hidden>
+        Pots are listed with who can win each. Award them by hand strength, best hand
+        first. Nothing here is saved — the <a href="/casino/texasholdem">full table</a>
+        keeps a log.
+    </p>
+</div>
+
+<template id="unevenRowTemplate">
+    <div class="unevenRow">
+        <span class="unevenRowLabel"></span>
+        <div class="unevenAmountWrap">
+            <span class="unevenCurrency">$</span>
+            <input type="text" class="unevenAmount" inputmode="decimal" autocomplete="off" placeholder="0" />
+        </div>
+        <button type="button" class="unevenFoldBtn" aria-pressed="false">Folded</button>
+        <button type="button" class="unevenRemoveBtn" aria-label="Remove player">✕</button>
+    </div>
+</template>
+
+@section Styles {
+    <link href="/css/casino/quicksplit.css?v=@ViewData["cssVersion"]" rel="stylesheet" type="text/css" />
+}
+
+@section Scripts {
+    <script src="~/js/casino/holdem/money.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/splitCalculator.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/potCalculator.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/casino/holdem/quickSplit.js?v=@ViewData["cssVersion"]"></script>
+}

JoshHeaps.Net/Pages/Casino/TexasHoldem/QuickSplit.cshtml.cs

@@ -0,0 +1,11 @@
+using Microsoft.AspNetCore.Mvc.RazorPages;
+
+namespace JoshHeaps.Net.Pages.Casino.TexasHoldem
+{
+    public class QuickSplitModel : PageModel
+    {
+        public void OnGet()
+        {
+        }
+    }
+}

JoshHeaps.Net/Pages/Chess.cshtml

@@ -6,7 +6,14 @@
 }
 
 <div id="chessContainer">
-    <div id="boardContainer">
+    <section id="boardArea">
+        <div class="playerBar" id="topPlayerBar">
+            <span class="playerDot black"></span>
+            <span class="playerName">Opponent</span>
+            <div class="capturedTray" id="captured-top"></div>
+            <span class="advantage" id="advantage-top"></span>
+        </div>
+
         <div id="chessBoard">
             <!-- Placeholder squares -->
             @for (int i = 0; i < 64; i++)
@@ -14,18 +21,41 @@
                 <div id="square-@i" class="chessSquare @( (i + i / 8) % 2 == 0 ? "light" : "dark" )"></div>
             }
         </div>
-    </div>
 
-    <div id="textContainer" class="sideContent">
-        <h1>Chess</h1>
-        <p>Click a button to start a game :)</p>
-    </div>
+        <div class="playerBar" id="bottomPlayerBar">
+            <span class="playerDot white"></span>
+            <span class="playerName">You</span>
+            <div class="capturedTray" id="captured-bottom"></div>
+            <span class="advantage" id="advantage-bottom"></span>
+        </div>
+    </section>
 
-    <div id="buttonContainer" class="sideContent">
-        <button id="startGameBtn" onclick="startNewGame()">Start New Game</button>
-        <button id="startCPUGame" onclick="startCPUGame()">Vs CPU</button>
-        <button id="copyPgnBtn" onclick="copyPgn()" style="display: none">Copy PGN</button>
-        <a id="watchLink" href="/watch">Watch other games →</a>
+    <aside id="gamePanel">
+        <header class="panelHeader">
+            <span class="panelLogo">&#9822;</span>
+            <h1>Chess</h1>
+            <button id="menuClose" class="iconBtn" aria-label="Close menu" onclick="closeMenu()">&times;</button>
+        </header>
+
+        <div id="moveList">
+            <p class="movePlaceholder">Moves will appear here once a game begins.</p>
+        </div>
+
+        <div id="statusLine">Start a game to play.</div>
+
+        <div id="panelButtons">
+            <button id="startGameBtn" class="btn btn-primary" onclick="startNewGame()">New Game</button>
+            <button id="startCPUGame" class="btn btn-secondary" onclick="startCPUGame()">Play vs CPU</button>
+            <button id="copyPgnBtn" class="btn btn-ghost" onclick="copyPgn()" style="display: none">Copy PGN</button>
+            <a id="watchLink" href="/watch">Watch other games &rarr;</a>
+        </div>
+    </aside>
+
+    <div id="menuBackdrop" onclick="closeMenu()"></div>
+
+    <div id="mobileBar">
+        <span id="mobileStatus">Start a game to play.</span>
+        <button id="menuToggle" class="btn btn-primary" onclick="toggleMenu()">Menu</button>
     </div>
 </div>
 
@@ -59,19 +89,31 @@
     </div>
 </div>
 
+<div id="colorModal" style="display: none;">
+    <p>Play as:</p>
+    <div id="colorButtonContainer">
+        <button onclick="selectColor('white')">White</button>
+        <button onclick="selectColor('black')">Black</button>
+        <button onclick="selectColor('random')">Random</button>
+    </div>
+</div>
+
 @section Scripts {
     <script src="~/js/signalr/signalr.min.js"></script>
-    <script src="~/js/ChessScripts/GameState.js"></script>
-    <script src="~/js/ChessScripts/ChessUtils.js"></script>
-    <script src="~/js/ChessScripts/ChessAPI.js"></script>
-    <script src="~/js/ChessScripts/ChessSignalR.js"></script>
-    <script src="~/js/ChessScripts/ChessInteractions.js"></script>
-    <script src="~/js/ChessScripts/ChessBoard.js"></script>
-    <script src="~/js/ChessScripts/ChessModals.js"></script>
-    <script src="~/js/ChessScripts/chessMain.js"></script>
+    <script src="~/js/ChessScripts/GameState.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/ChessScripts/ChessUtils.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/ChessScripts/ChessAPI.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/ChessScripts/ChessSignalR.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/ChessScripts/ChessInteractions.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/ChessScripts/ChessBoard.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/ChessScripts/ChessModals.js?v=@ViewData["cssVersion"]"></script>
+    <script src="~/js/ChessScripts/chessMain.js?v=@ViewData["cssVersion"]"></script>
 }
 
 @section Styles {
+    <link rel="preconnect" href="https://fonts.googleapis.com" />
+    <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
+    <link href="https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700;800&display=swap" rel="stylesheet" />
     <link rel="stylesheet" href="~/css/chess/game.css?v=@ViewData["cssVersion"]" />
     <link rel="stylesheet" href="~/css/chess/site.css?v=@ViewData["cssVersion"]" />
 }

JoshHeaps.Net/Pages/Index.cshtml

@@ -64,6 +64,7 @@
         <button class="demoButton" onclick="window.location.href='/watch'">Watch Live Chess</button>
         <button class="demoButton" onclick="window.location.href='/particles'">Particle Simulator</button>
         <button class="demoButton" onclick="window.location.href='/memorylane'">Memory Lane</button>
+        <button class="demoButton" onclick="window.location.href='/casino'">Casino Games</button>
         <button class="demoButton" onclick="window.location.href='https://media.joshheaps.net'">Cloud Image Storage</button>
         <button id="MoreFiller" class="demoButton">More coming soon...</button>
     </div>

JoshHeaps.Net/Pages/Watch.cshtml

@@ -9,16 +9,43 @@
     <h1>Live Chess</h1>
     <p id="watchStatus">Loading games…</p>
     <div id="watchControls">
-        <label for="cpuDifficulty">Difficulty</label>
-        <select id="cpuDifficulty">
-            @for (int i = 1; i <= 20; i++)
-            {
-                <option value="@i" @(i == 4 ? "selected" : "")>@i</option>
-            }
-        </select>
+        <fieldset class="enginePicker">
+            <legend>White</legend>
+            <select id="whiteEngine">
+                <option value="custom">Custom (v1)</option>
+                <option value="customLearned" selected>Custom (Learned)</option>
+                <option value="stockfish">Stockfish</option>
+            </select>
+            <select id="whiteSkill">
+                @for (int i = 1; i <= 20; i++)
+                {
+                    <option value="@i" @(i == 4 ? "selected" : "")>@i</option>
+                }
+            </select>
+        </fieldset>
+        <fieldset class="enginePicker">
+            <legend>Black</legend>
+            <select id="blackEngine">
+                <option value="custom" selected>Custom (v1)</option>
+                <option value="customLearned">Custom (Learned)</option>
+                <option value="stockfish">Stockfish</option>
+            </select>
+            <select id="blackSkill">
+                @for (int i = 1; i <= 20; i++)
+                {
+                    <option value="@i" @(i == 4 ? "selected" : "")>@i</option>
+                }
+            </select>
+        </fieldset>
         <button id="startCpuVsCpu" onclick="Spectate.startCpuGame()">Watch CPU vs CPU</button>
+        <fieldset class="enginePicker">
+            <legend>Auto-train games</legend>
+            <input id="autoTrainCount" type="number" min="0" max="16" step="1" />
+            <button id="applyAutoTrain" onclick="Spectate.setAutoTrainCount()">Apply</button>
+        </fieldset>
     </div>
     <a id="backToPlay" href="/chess">← Play a game</a>
+    <a id="viewWeights" href="/weights">View learned weights →</a>
 </div>
 
 <div id="gamesFeed"></div>

JoshHeaps.Net/Pages/Weights.cshtml

@@ -0,0 +1,44 @@
+@page
+@model JoshHeaps.Net.Pages.WeightsModel
+@{
+    Layout = "_Layout";
+    ViewData["Title"] = "Learned Weights";
+}
+
+<div id="weightsHeader">
+    <h1>Learned Piece-Square Weights</h1>
+    <p id="weightsStatus">Where the learned engine thinks each piece belongs.</p>
+    <div id="weightsControls">
+        <div class="heatLegend">
+            <span>low</span>
+            <span class="legendBar"></span>
+            <span>high</span>
+        </div>
+        <button id="refreshWeights" onclick="Weights.refresh()">Refresh</button>
+    </div>
+    <a id="backToWatch" href="/watch">← Watch / train</a>
+</div>
+
+<section class="weightsSection">
+    <h2>Feature weights</h2>
+    <p class="sectionHint">Learned value of each contextual feature (per normalized unit). Mobility is per piece type; passed pawns are endgame-weighted, king safety midgame-weighted.</p>
+    <div id="featureWeights" class="featurePanel"></div>
+</section>
+
+<section class="weightsSection">
+    <h2>Midgame tables</h2>
+    <div id="weightsGridMg" class="weightsGrid"></div>
+</section>
+
+<section class="weightsSection">
+    <h2>Endgame tables</h2>
+    <div id="weightsGridEg" class="weightsGrid"></div>
+</section>
+
+@section Scripts {
+    <script src="~/js/ChessScripts/Weights.js"></script>
+}
+
+@section Styles {
+    <link rel="stylesheet" href="~/css/chess/weights.css?v=@ViewData["cssVersion"]" />
+}

JoshHeaps.Net/Pages/Weights.cshtml.cs

@@ -0,0 +1,11 @@
+using Microsoft.AspNetCore.Mvc.RazorPages;
+
+namespace JoshHeaps.Net.Pages
+{
+    public class WeightsModel : PageModel
+    {
+        public void OnGet()
+        {
+        }
+    }
+}

JoshHeaps.Net/Pages/_Layout.cshtml

@@ -1,6 +1,6 @@
 @{
     Layout = null;
-    ViewData["cssVersion"] = "1.0.5"; // <--- change this once to bust cache
+    ViewData["cssVersion"] = "1.0.8"; // <--- change this once to bust cache
 }
 
 <!DOCTYPE html>

JoshHeaps.Net/Program.cs

@@ -23,12 +23,23 @@ builder.Services.AddSingleton<IChessService, ChessService>();
 builder.Services.AddSingleton<IBackgroundTaskQueue, BackgroundTaskQueue>();
 
 builder.Services.Configure<ChessEngineOptions>(configuration.GetSection(ChessEngineOptions.SectionName));
+builder.Services.AddSingleton<ILearnedWeightsStore, LearnedWeightsStore>();
 builder.Services.AddSingleton<IChessEngineFactory, ChessEngineFactory>();
 builder.Services.AddSingleton<IComputerMoveOrchestrator, ComputerMoveOrchestrator>();
+builder.Services.AddSingleton<IGameStore, GameStore>();
+builder.Services.AddSingleton<ISelfPlayCoordinator, SelfPlayCoordinator>();
+builder.Services.AddSingleton<AutoTrainingSettings>();
 
 if (!builder.Environment.IsDevelopment())
+{
     builder.Services.AddHostedService<AutoIpUpdateService>();
 
+    // Continuously train the learned engine against Stockfish in the background. Toggle off
+    // via ChessEngine:AutoTrain (env ChessEngine__AutoTrain=false) without a redeploy.
+    if (configuration.GetValue($"{ChessEngineOptions.SectionName}:{nameof(ChessEngineOptions.AutoTrain)}", true))
+        builder.Services.AddHostedService<AutoTrainingService>();
+}
+
 var app = builder.Build();
 
 // Configure the HTTP request pipeline.

JoshHeaps.Net/Services/Implementations/AutoTrainingService.cs

@@ -0,0 +1,73 @@
+using JoshHeaps.Net.Services.Interfaces;
+
+namespace JoshHeaps.Net.Services.Implementations;
+
+/// <summary>
+/// Continuously trains the learned engine in the background by keeping a configurable number of
+/// self-play games running — the learned engine (skill 6) against Stockfish (skill 20), alternating
+/// which color Stockfish takes so the model trains on both. The target count is read live from
+/// <see cref="AutoTrainingSettings"/> (adjustable from the website): when a game finishes another
+/// starts to refill the pool, raising the count starts more, and lowering it lets the surplus drain
+/// as games finish (0 pauses training). Registered only outside Development and gated by the
+/// ChessEngine:AutoTrain config flag.
+/// </summary>
+public sealed class AutoTrainingService(
+    ISelfPlayCoordinator coordinator,
+    AutoTrainingSettings settings,
+    ILogger<AutoTrainingService> logger) : BackgroundService
+{
+    private const int LearnedSkill = 6;
+    private const int StockfishSkill = 20;
+    private static readonly TimeSpan _restartBackoff = TimeSpan.FromSeconds(5);
+    private static readonly TimeSpan _pollInterval = TimeSpan.FromSeconds(2);
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        var running = new List<Task>();
+        int started = 0;
+
+        while (!stoppingToken.IsCancellationRequested)
+        {
+            running.RemoveAll(t => t.IsCompleted);
+
+            int desired = settings.GameCount;
+            bool startFailed = false;
+
+            while (running.Count < desired && !stoppingToken.IsCancellationRequested)
+            {
+                // Alternate Stockfish's color so the learned engine trains as both white and black.
+                var config = started++ % 2 == 0
+                    ? new SelfPlayConfig(ChessEngineKind.CustomLearned, LearnedSkill, ChessEngineKind.Stockfish, StockfishSkill)
+                    : new SelfPlayConfig(ChessEngineKind.Stockfish, StockfishSkill, ChessEngineKind.CustomLearned, LearnedSkill);
+
+                try
+                {
+                    var (_, completion) = coordinator.StartGame(config, stoppingToken);
+                    running.Add(completion);
+                }
+                catch (Exception ex)
+                {
+                    // Most likely an engine failing to start (e.g. Stockfish). Back off so a
+                    // persistent failure doesn't spin a tight loop, then try again.
+                    logger.LogError(ex, "Failed to start an auto-training game; retrying after backoff.");
+                    startFailed = true;
+                    break;
+                }
+            }
+
+            try
+            {
+                if (startFailed)
+                    await Task.Delay(_restartBackoff, stoppingToken);
+                else if (running.Count > 0)
+                    // Wake when any game finishes (to refill) or after a short poll (to pick up a
+                    // count increase promptly).
+                    await Task.WhenAny(Task.WhenAny(running), Task.Delay(_pollInterval, stoppingToken));
+                else
+                    // Pool is empty (count is 0) — just poll for the count to change.
+                    await Task.Delay(_pollInterval, stoppingToken);
+            }
+            catch (OperationCanceledException) { break; }
+        }
+    }
+}

JoshHeaps.Net/Services/Implementations/AutoTrainingSettings.cs

@@ -0,0 +1,31 @@
+using Microsoft.Extensions.Options;
+
+namespace JoshHeaps.Net.Services.Implementations;
+
+/// <summary>
+/// Runtime-adjustable auto-training settings. Singleton so the value set from the website (via the
+/// chess controller) is seen live by the background <see cref="AutoTrainingService"/>. Seeded from
+/// <see cref="ChessEngineOptions.AutoTrainGameCount"/> and clamped to a sane range.
+/// </summary>
+public sealed class AutoTrainingSettings
+{
+    /// <summary>Upper bound on concurrent auto-training games (each spawns a Stockfish + a learned engine).</summary>
+    public const int MaxGames = 16;
+
+    private int _gameCount;
+
+    public AutoTrainingSettings(IOptions<ChessEngineOptions> options)
+        => _gameCount = Clamp(options.Value.AutoTrainGameCount);
+
+    /// <summary>
+    /// Number of auto-training games to keep running concurrently. 0 pauses auto-training.
+    /// Reads/writes are atomic; the background service reads this every cycle.
+    /// </summary>
+    public int GameCount
+    {
+        get => Volatile.Read(ref _gameCount);
+        set => Volatile.Write(ref _gameCount, Clamp(value));
+    }
+
+    private static int Clamp(int n) => Math.Clamp(n, 0, MaxGames);
+}

JoshHeaps.Net/Services/Implementations/BlogService.cs

@@ -1,4 +1,4 @@
-using System.Collections.Concurrent;
+using System.Collections.Concurrent;
 using System.Text.Json;
 using JoshHeaps.Net.Models;
 using JoshHeaps.Net.Services.Interfaces;
@@ -10,6 +10,7 @@ public class BlogService : IBlogService
     private readonly HttpClient _httpClient;
     private readonly ILogger<BlogService> _logger;
     private readonly TimeSpan _cacheTtl = TimeSpan.FromMinutes(5);
+    private readonly TimeSpan _staleGrace = TimeSpan.FromHours(1);
 
     private readonly ConcurrentDictionary<string, CacheEntry> _cache = new();
 
@@ -65,7 +66,9 @@ public class BlogService : IBlogService
 
     private async Task<T?> GetCachedAsync<T>(string key, Func<Task<T?>> factory) where T : class
     {
-        if (_cache.TryGetValue(key, out var entry) && entry.ExpiresAt > DateTime.UtcNow)
+        _cache.TryGetValue(key, out var entry);
+
+        if (entry is not null && entry.ExpiresAt > DateTime.UtcNow)
             return (T?)entry.Value;
 
         var result = await factory();
@@ -73,15 +76,26 @@ public class BlogService : IBlogService
         if (result is not null)
         {
             _cache[key] = new CacheEntry(result, DateTime.UtcNow.Add(_cacheTtl));
+            return result;
         }
-        else if (entry is not null)
+
+        return entry is null ? null : ServeStale<T>(key, entry);
+    }
+
+    // Stale entries are dropped once the grace window closes so that a dead API fails the same
+    // way for every key. Serving them indefinitely let a cached post list render next to 404s on
+    // the posts themselves, which reads as a site bug rather than an outage.
+    private T? ServeStale<T>(string key, CacheEntry entry) where T : class
+    {
+        if (entry.ExpiresAt.Add(_staleGrace) > DateTime.UtcNow)
         {
-            // API unreachable — serve stale cache
-            _logger.LogWarning("Serving stale cache for key {Key}", key);
+            _logger.LogWarning("Blog API unreachable, serving stale cache for key {Key}", key);
             return (T?)entry.Value;
         }
 
-        return result;
+        _cache.TryRemove(key, out _);
+        _logger.LogError("Blog API unreachable for over {StaleGrace}, dropping stale cache for key {Key}", _staleGrace, key);
+        return null;
     }
 
     public void ClearCache()

JoshHeaps.Net/Services/Implementations/ChessEngineFactory.cs

@@ -7,7 +7,10 @@ namespace JoshHeaps.Net.Services.Implementations;
 public enum ChessEngineKind
 {
     Stockfish,
-    Custom
+    Custom,
+
+    /// <summary>The custom engine with the reinforcement-learned piece-square evaluation.</summary>
+    CustomLearned
 }
 
 /// <summary>Configuration selecting which <see cref="IChessEngine"/> to use.</summary>
@@ -16,17 +19,46 @@ public sealed class ChessEngineOptions
     public const string SectionName = "ChessEngine";
 
     public ChessEngineKind Engine { get; set; } = ChessEngineKind.Stockfish;
+
+    /// <summary>
+    /// Absolute path to the learned-weights file. Leave null to default to
+    /// <c>{ContentRoot}/chess-data/learned-weights.txt</c> (fine for local dev). In
+    /// production set this to a stable, service-writable location OUTSIDE the deploy
+    /// directory (e.g. <c>/var/lib/joshheaps/chess-data/learned-weights.txt</c>) so the
+    /// trained weights survive deploys and avoid deploy-user vs service-user permission
+    /// clashes. Override via the <c>ChessEngine__WeightsPath</c> environment variable.
+    /// </summary>
+    public string? WeightsPath { get; set; }
+
+    /// <summary>
+    /// When true (and outside Development), a background service continuously plays the learned
+    /// engine against Stockfish to train it. Set to false to stop auto-training without a
+    /// redeploy. Override via the <c>ChessEngine__AutoTrain</c> environment variable.
+    /// </summary>
+    public bool AutoTrain { get; set; } = true;
+
+    /// <summary>
+    /// How many auto-training games run concurrently (when <see cref="AutoTrain"/> is on). This is
+    /// the starting value; it can be changed at runtime from the website. Override the default via
+    /// the <c>ChessEngine__AutoTrainGameCount</c> environment variable.
+    /// </summary>
+    public int AutoTrainGameCount { get; set; } = 2;
 }
 
 /// <summary>Creates the configured <see cref="IChessEngine"/> per game.</summary>
-public sealed class ChessEngineFactory(IOptions<ChessEngineOptions> options) : IChessEngineFactory
+public sealed class ChessEngineFactory(
+    IOptions<ChessEngineOptions> options,
+    ILearnedWeightsStore weightsStore) : IChessEngineFactory
 {
     private readonly ChessEngineKind _kind = options.Value.Engine;
 
-    public IChessEngine Create(int skill) => _kind switch
+    public IChessEngine Create(int skill) => Create(skill, _kind);
+
+    public IChessEngine Create(int skill, ChessEngineKind kind) => kind switch
     {
         ChessEngineKind.Custom => new CustomChessEngine(skill),
+        ChessEngineKind.CustomLearned => new CustomChessEngine(skill, EngineVariant.Learned, weightsStore.WeightsFilePath),
         ChessEngineKind.Stockfish => new Stockfish(skill),
-        _ => throw new InvalidOperationException($"Unknown chess engine '{_kind}'.")
+        _ => throw new InvalidOperationException($"Unknown chess engine '{kind}'.")
     };
 }

JoshHeaps.Net/Services/Implementations/ComputerMoveOrchestrator.cs

@@ -11,23 +11,60 @@ namespace JoshHeaps.Net.Services.Implementations;
 /// </summary>
 public sealed class ComputerMoveOrchestrator(
     IHubContext<ChessHub> chessHub,
-    IChessService chessService) : IComputerMoveOrchestrator
+    IChessService chessService,
+    ILearnedWeightsStore weightsStore) : IComputerMoveOrchestrator
 {
-    public async Task<(MoveDto move, MoveResultDto result)> PlayAsync(GameState state, IChessEngine engine)
+    public async Task<(MoveDto move, MoveResultDto result)> PlayAsync(GameState state)
     {
+        var engine = (state.CurrentPlayer == PieceColor.White ? state.WhiteComputer : state.BlackComputer)
+            ?? throw new InvalidOperationException($"No engine is set for {state.CurrentPlayer} in game {state.GameId}.");
+
         var uci = await engine.GetBestMoveAsync(state.ToFen(), state.RepetitionHistory());
+        var move = uci.ToMoveDto(state, CurrentPlayerId(state));
 
-        var move = uci.ToMoveDto(
-            state,
-            state.CurrentPlayer == PieceColor.White
-                ? state.WhitePlayerId
-                : state.BlackPlayerId);
+        return await ApplyAndBroadcastAsync(state, move);
+    }
 
+    public async Task PlayRandomMoveAsync(GameState state)
+    {
+        var options = chessService.GetAllLegalMoves(state);
+
+        // No legal moves means the game is already over; let the caller's loop detect it.
+        if (options.Count == 0)
+            return;
+
+        var (piece, moves) = options[Random.Shared.Next(options.Count)];
+        var target = moves[Random.Shared.Next(moves.Count)];
+
+        var move = new MoveDto
+        {
+            GameId = state.GameId,
+            PlayerId = CurrentPlayerId(state),
+            PieceId = piece.Id,
+            SourceRow = piece.Position.Row,
+            SourceCol = piece.Position.Col,
+            TargetRow = target.Row,
+            TargetCol = target.Col,
+            PromotionChoice = null   // a pawn cannot reach the last rank within the opening plies
+        };
+
+        await ApplyAndBroadcastAsync(state, move);
+    }
+
+    private async Task<(MoveDto move, MoveResultDto result)> ApplyAndBroadcastAsync(GameState state, MoveDto move)
+    {
         var result = chessService.MakeMove(state, move);
 
+        // Record the played position for training (no-op for non-training games).
+        if (state.Trainer != nint.Zero)
+            weightsStore.Record(state.Trainer, state.ToFen());
+
         await chessHub.Clients.Group(state.GameId.ToString())
-            .SendAsync("ReceiveMoveUpdate", state.GameId.ToString(), move, result);
+            .SendAsync("ReceiveMoveUpdate", state.GameId.ToString(), move, result, state.ToDto());
 
         return (move, result);
     }
+
+    private static Guid CurrentPlayerId(GameState state) =>
+        state.CurrentPlayer == PieceColor.White ? state.WhitePlayerId : state.BlackPlayerId;
 }

JoshHeaps.Net/Services/Implementations/CustomChessEngine.cs

@@ -5,6 +5,16 @@ using System.Runtime.InteropServices;
 
 namespace JoshHeaps.Net.Services.Implementations;
 
+/// <summary>Which evaluation the native engine uses.</summary>
+public enum EngineVariant
+{
+    /// <summary>The hand-crafted evaluation.</summary>
+    Classic,
+
+    /// <summary>Material plus a learned per-square bonus table loaded from a weights file.</summary>
+    Learned
+}
+
 /// <summary>
 /// Middleman wrapper over the native custom chess engine (chess_engine.dll / libchess_engine.so).
 /// Shares <see cref="IChessEngine"/> with <see cref="Stockfish"/> so the two are swappable.
@@ -16,11 +26,17 @@ public sealed partial class CustomChessEngine : IChessEngine
 
     public int Skill { get; }
 
-    public CustomChessEngine(int skill = 20)
+    public CustomChessEngine(int skill = 20, EngineVariant variant = EngineVariant.Classic, string? weightsPath = null)
     {
         Skill = skill;
 
-        var handle = NativeMethods.engine_create($"skill={skill}");
+        // weights= must come last: the native side reads the path as the rest of the
+        // string, which lets it contain ';' and spaces.
+        var options = variant == EngineVariant.Learned
+            ? $"skill={skill};variant=learned;weights={weightsPath}"
+            : $"skill={skill}";
+
+        var handle = NativeMethods.engine_create(options);
 
         if (handle == IntPtr.Zero)
             throw new InvalidOperationException("Native chess engine failed to initialize (engine_create returned null).");
@@ -79,8 +95,9 @@ public sealed partial class CustomChessEngine : IChessEngine
     /// <summary>
     /// P/Invoke surface for chess_engine.(dll|so). The resolver maps the logical name
     /// "chess_engine" to the platform binary in the Resources folder (mirrors Stockfish).
+    /// Internal so <see cref="LearnedWeightsStore"/> can share the single import resolver.
     /// </summary>
-    private static partial class NativeMethods
+    internal static partial class NativeMethods
     {
         private const string LibName = "chess_engine";
 
@@ -115,5 +132,31 @@ public sealed partial class CustomChessEngine : IChessEngine
         [LibraryImport(LibName)]
         [UnmanagedCallConv(CallConvs = [typeof(CallConvCdecl)])]
         internal static partial void engine_destroy(IntPtr engine);
+
+        // ---- Learned-weights / training ABI (see chess_engine.h) ----
+
+        [LibraryImport(LibName, StringMarshalling = StringMarshalling.Utf8)]
+        [UnmanagedCallConv(CallConvs = [typeof(CallConvCdecl)])]
+        internal static partial void learned_load(string path);
+
+        [LibraryImport(LibName)]
+        [UnmanagedCallConv(CallConvs = [typeof(CallConvCdecl)])]
+        internal static unsafe partial int weights_snapshot(int* outBuf, int outLen);
+
+        [LibraryImport(LibName)]
+        [UnmanagedCallConv(CallConvs = [typeof(CallConvCdecl)])]
+        internal static partial IntPtr trainer_create();
+
+        [LibraryImport(LibName, StringMarshalling = StringMarshalling.Utf8)]
+        [UnmanagedCallConv(CallConvs = [typeof(CallConvCdecl)])]
+        internal static partial void trainer_record(IntPtr trainer, string fen);
+
+        [LibraryImport(LibName)]
+        [UnmanagedCallConv(CallConvs = [typeof(CallConvCdecl)])]
+        internal static partial void trainer_apply(IntPtr trainer, int winner, double weight);
+
+        [LibraryImport(LibName)]
+        [UnmanagedCallConv(CallConvs = [typeof(CallConvCdecl)])]
+        internal static partial void trainer_destroy(IntPtr trainer);
     }
 }

JoshHeaps.Net/Services/Implementations/GameStore.cs

@@ -0,0 +1,69 @@
+using System.Collections.Concurrent;
+using JoshHeaps.Net.Models;
+using JoshHeaps.Net.Services.Interfaces;
+
+namespace JoshHeaps.Net.Services.Implementations;
+
+/// <summary>
+/// In-memory game registry with a delayed-removal lifecycle. Singleton: the game state is
+/// process-wide, not per-request, so it lives in a service rather than static controller fields.
+/// </summary>
+public sealed class GameStore(ILearnedWeightsStore weightsStore) : IGameStore
+{
+    private readonly ConcurrentDictionary<Guid, GameState> _games = [];
+    private readonly ConcurrentDictionary<Guid, Task> _removalTasks = [];
+    private readonly ConcurrentDictionary<Guid, CancellationTokenSource> _removalCts = [];
+
+    public void Add(GameState game) => _games[game.GameId] = game;
+
+    public bool TryGet(Guid id, out GameState game) => _games.TryGetValue(id, out game!);
+
+    public bool Contains(Guid id) => _games.ContainsKey(id);
+
+    public IReadOnlyCollection<GameState> All => [.. _games.Values];
+
+    public void ScheduleRemove(Guid id, TimeSpan delay)
+    {
+        if (_removalCts.TryRemove(id, out var oldCts))
+        {
+            oldCts.Cancel();
+            oldCts.Dispose();
+        }
+
+        var cts = new CancellationTokenSource();
+        _removalCts[id] = cts;
+
+        _removalTasks[id] = Task.Run(async () =>
+        {
+            try
+            {
+                await Task.Delay(delay, cts.Token);
+
+                if (_games.TryGetValue(id, out var game))
+                {
+                    if (game.WhiteComputer is not null)
+                        await game.WhiteComputer.DisposeAsync();
+                    if (game.BlackComputer is not null)
+                        await game.BlackComputer.DisposeAsync();
+
+                    // Free the trainer if the game never reached ApplyLearning (e.g. timed out).
+                    if (game.Trainer != nint.Zero)
+                    {
+                        weightsStore.DestroyTrainer(game.Trainer);
+                        game.Trainer = nint.Zero;
+                    }
+                }
+
+                _games.Remove(id, out _);
+            }
+            catch (OperationCanceledException) { }
+            finally
+            {
+                if (_removalCts.TryGetValue(id, out var currentCts) && currentCts == cts)
+                    _removalCts.TryRemove(id, out _);
+
+                cts.Dispose();
+            }
+        });
+    }
+}

JoshHeaps.Net/Services/Implementations/LearnedWeightsStore.cs

@@ -0,0 +1,84 @@
+using JoshHeaps.Net.Models;
+using JoshHeaps.Net.Services.Interfaces;
+using Microsoft.Extensions.Options;
+
+namespace JoshHeaps.Net.Services.Implementations;
+
+/// <summary>
+/// Managed facade over the native learned-weights model (see <see cref="ILearnedWeightsStore"/>).
+/// On construction it points the native engine at the weights file; everything else delegates
+/// to the shared native ABI in <see cref="CustomChessEngine"/>.
+/// </summary>
+public sealed class LearnedWeightsStore : ILearnedWeightsStore
+{
+    private const int Pieces = 6;       // Pawn..King
+    private const int Squares = 64;
+    private const int Features = 8;     // mobility N/B/R/Q, passed, isolated, doubled, king safety
+
+    public string WeightsFilePath { get; }
+
+    public LearnedWeightsStore(IHostEnvironment env, IOptions<ChessEngineOptions> options, ILogger<LearnedWeightsStore> logger)
+    {
+        // Prefer the configured path (production points this outside the deploy dir); fall
+        // back to the content root for local dev.
+        var configured = options.Value.WeightsPath;
+        WeightsFilePath = string.IsNullOrWhiteSpace(configured)
+            ? Path.Combine(env.ContentRootPath, "chess-data", "learned-weights.txt")
+            : configured;
+
+        // A missing/unwritable/misconfigured path must not take down the whole app — the
+        // learned engine just plays from a neutral table and can't persist training.
+        try
+        {
+            Directory.CreateDirectory(Path.GetDirectoryName(WeightsFilePath)!);
+            CustomChessEngine.NativeMethods.learned_load(WeightsFilePath);
+        }
+        catch (Exception ex)
+        {
+            logger.LogError(ex,
+                "Could not initialize the learned-weights store at {Path}. The learned engine will " +
+                "play from a neutral table and training will not persist. In production set " +
+                "ChessEngine:WeightsPath (env ChessEngine__WeightsPath) to a service-writable directory.",
+                WeightsFilePath);
+        }
+    }
+
+    public nint CreateTrainer() => CustomChessEngine.NativeMethods.trainer_create();
+
+    public void Record(nint trainer, string fen) =>
+        CustomChessEngine.NativeMethods.trainer_record(trainer, fen);
+
+    public void ApplyResult(nint trainer, PieceColor winner, double weight) =>
+        CustomChessEngine.NativeMethods.trainer_apply(trainer, winner == PieceColor.White ? 0 : 1, weight);
+
+    public void DestroyTrainer(nint trainer) =>
+        CustomChessEngine.NativeMethods.trainer_destroy(trainer);
+
+    public LearnedWeightsSnapshot Snapshot()
+    {
+        const int total = Pieces * Squares * 2 + Features;
+        var buffer = new int[total];
+
+        unsafe
+        {
+            fixed (int* p = buffer)
+                CustomChessEngine.NativeMethods.weights_snapshot(p, total);
+        }
+
+        var mg = new int[Pieces][];
+        var eg = new int[Pieces][];
+
+        for (int piece = 0; piece < Pieces; piece++)
+        {
+            mg[piece] = new int[Squares];
+            eg[piece] = new int[Squares];
+            Array.Copy(buffer, piece * Squares, mg[piece], 0, Squares);
+            Array.Copy(buffer, Pieces * Squares + piece * Squares, eg[piece], 0, Squares);
+        }
+
+        var features = new int[Features];
+        Array.Copy(buffer, Pieces * Squares * 2, features, 0, Features);
+
+        return new LearnedWeightsSnapshot(mg, eg, features);
+    }
+}

JoshHeaps.Net/Services/Implementations/SelfPlayCoordinator.cs

@@ -0,0 +1,257 @@
+using JoshHeaps.Net.Models;
+using JoshHeaps.Net.Services.Interfaces;
+
+namespace JoshHeaps.Net.Services.Implementations;
+
+/// <summary>
+/// Runs CPU-vs-CPU games: builds the game and engines, plays a randomized opening (for training
+/// variety), drives the move loop to completion, then trains the learned engine from the result.
+/// </summary>
+public sealed class SelfPlayCoordinator(
+    IChessService chessService,
+    IChessEngineFactory engineFactory,
+    IComputerMoveOrchestrator orchestrator,
+    ILearnedWeightsStore weightsStore,
+    IGameStore gameStore) : ISelfPlayCoordinator
+{
+    private static readonly TimeSpan _computerGameTimeout = TimeSpan.FromHours(1);
+    private static readonly TimeSpan _selfPlayMoveDelay = TimeSpan.FromSeconds(1);
+    private static readonly TimeSpan _selfPlayResultTimeout = TimeSpan.FromSeconds(30);
+
+    // Abandon a game that goes this long without a move being played — i.e. an engine (usually
+    // Stockfish) that crashed or froze. The game is killed with no result recorded; if it was an
+    // auto-training game the trainer schedules a replacement once this one's task completes.
+    private static readonly TimeSpan _idleTimeout = TimeSpan.FromSeconds(60);
+
+    // Plies of random legal moves at the start of a training game, so self-play and
+    // engine-vs-engine games explore different lines instead of replaying one game.
+    private const int _openingRandomPlies = 4;
+
+    public (Guid GameId, Task Completion) StartGame(SelfPlayConfig config, CancellationToken cancellationToken = default)
+    {
+        var whiteComputer = engineFactory.Create(config.WhiteSkill, config.WhiteKind);
+        IChessEngine blackComputer;
+        try
+        {
+            blackComputer = engineFactory.Create(config.BlackSkill, config.BlackKind);
+        }
+        catch
+        {
+            // Don't leak the first engine if the second fails to start (e.g. Stockfish process).
+            whiteComputer.DisposeAsync().AsTask().GetAwaiter().GetResult();
+            throw;
+        }
+
+        var gameState = chessService.CreateNewGame();
+        gameState.IsVsComputer = true;
+        gameState.IsComputerVsComputer = true;
+        gameState.WhiteJoined = true;
+        gameState.BlackJoined = true;
+        gameState.WhitePlayerId = Guid.NewGuid();
+        gameState.BlackPlayerId = Guid.NewGuid();
+        gameState.WhiteEngineKind = config.WhiteKind;
+        gameState.BlackEngineKind = config.BlackKind;
+        gameState.WhiteComputer = whiteComputer;
+        gameState.BlackComputer = blackComputer;
+
+        // When the learned engine is playing, attach a trainer so the outcome can train it.
+        if (config.WhiteKind == ChessEngineKind.CustomLearned || config.BlackKind == ChessEngineKind.CustomLearned)
+            gameState.Trainer = weightsStore.CreateTrainer();
+
+        gameStore.Add(gameState);
+        gameStore.ScheduleRemove(gameState.GameId, _computerGameTimeout);
+
+        var completion = Task.Run(() => RunAsync(gameState, cancellationToken));
+        return (gameState.GameId, completion);
+    }
+
+    /// <summary>
+    /// Drives the game to completion, then trains from it. Never throws — a failure (or a frozen
+    /// engine) just ends the game and the trainer is always freed, so callers can await or ignore.
+    /// </summary>
+    private async Task RunAsync(GameState gameState, CancellationToken cancellationToken)
+    {
+        bool aborted = false;
+
+        try
+        {
+            // Give spectators a moment to join the SignalR group before the first move.
+            await Task.Delay(_selfPlayMoveDelay, cancellationToken);
+
+            // Training games open with random moves so they don't replay the same line.
+            if (gameState.Trainer != nint.Zero)
+                for (int i = 0; i < _openingRandomPlies && IsLive(gameState, cancellationToken); i++)
+                {
+                    await orchestrator.PlayRandomMoveAsync(gameState);
+                    await Task.Delay(_selfPlayMoveDelay, cancellationToken);
+                }
+
+            var lastMoveCount = gameState.MoveHistory.Count;
+            var lastProgress = DateTime.UtcNow;
+
+            while (IsLive(gameState, cancellationToken))
+            {
+                await PlayMoveWithTimeoutAsync(gameState, cancellationToken);
+
+                // Watchdog: abandon the game if it stops making moves (a crashed or frozen engine
+                // can leave PlayAsync returning without progressing). Reset the clock on a real
+                // move; otherwise bail once nothing has happened for the idle timeout.
+                if (gameState.MoveHistory.Count != lastMoveCount)
+                {
+                    lastMoveCount = gameState.MoveHistory.Count;
+                    lastProgress = DateTime.UtcNow;
+                }
+                else if (DateTime.UtcNow - lastProgress > _idleTimeout)
+                    throw new TimeoutException("no move played within the idle timeout");
+
+                await Task.Delay(_selfPlayMoveDelay, cancellationToken);
+            }
+        }
+        catch (OperationCanceledException) { aborted = true; /* service shutting down */ }
+        catch (TimeoutException)
+        {
+            aborted = true;
+            Console.WriteLine($"Self-play game {gameState.GameId} abandoned: no move for over " +
+                              $"{_idleTimeout.TotalSeconds:n0}s (likely a crashed or frozen engine).");
+        }
+        catch (Exception ex)
+        {
+            aborted = true;
+            Console.WriteLine($"Self-play game {gameState.GameId} stopped: {ex.Message}");
+        }
+
+        // A clean finish trains the learned engine; an abandoned game (cancelled, crashed, or
+        // idle past the timeout) records nothing and just frees its trainer.
+        if (aborted)
+            DiscardTraining(gameState);
+        else
+            ApplyLearning(gameState);
+
+        // A clean finish lingers briefly so spectators see the result; an abandoned game is torn
+        // down immediately so its engines (and any crashed/frozen Stockfish process) are released.
+        if (gameStore.Contains(gameState.GameId))
+            gameStore.ScheduleRemove(gameState.GameId, aborted ? TimeSpan.Zero : _selfPlayResultTimeout);
+    }
+
+    /// <summary>
+    /// Plays one engine move, abandoning it if it exceeds <see cref="_idleTimeout"/> (throwing
+    /// <see cref="TimeoutException"/>) so a single hung move can't block the loop forever. The
+    /// abandoned move's eventual fault — it errors once the game's engines are disposed — is
+    /// observed so it isn't an unobserved task exception.
+    /// </summary>
+    private async Task PlayMoveWithTimeoutAsync(GameState gameState, CancellationToken cancellationToken)
+    {
+        var play = orchestrator.PlayAsync(gameState);
+        try
+        {
+            await play.WaitAsync(_idleTimeout, cancellationToken);
+        }
+        catch (TimeoutException)
+        {
+            _ = play.ContinueWith(static t => { _ = t.Exception; }, TaskScheduler.Default);
+            throw;
+        }
+    }
+
+    private bool IsLive(GameState gameState, CancellationToken cancellationToken) =>
+        !cancellationToken.IsCancellationRequested
+        && gameStore.Contains(gameState.GameId)
+        && !IsGameOver(gameState);
+
+    private static bool IsGameOver(GameState gameState) =>
+        gameState.IsCheckmate || gameState.IsStalemate || gameState.IsThreefoldRepetition || gameState.IsForfeited;
+
+    /// <summary>
+    /// Feeds a finished training game's result into the learned weights, then frees the trainer.
+    /// A checkmate is a full-strength result; a material-imbalance draw is a half-strength win
+    /// for the lower-material side (holding a draw while down material is a success; only drawing
+    /// while up is a failure). A balanced draw, forfeit, or unfinished game teaches nothing.
+    /// </summary>
+    private void ApplyLearning(GameState gameState)
+    {
+        if (gameState.Trainer == nint.Zero)
+            return;
+
+        if (TryDetermineOutcome(gameState, out var winner, out var weight))
+            weightsStore.ApplyResult(gameState.Trainer, winner, weight);
+
+        weightsStore.DestroyTrainer(gameState.Trainer);
+        gameState.Trainer = nint.Zero;
+    }
+
+    /// <summary>
+    /// Frees an abandoned game's trainer without recording any result — a cancelled, crashed, or
+    /// idle-timed-out game teaches the model nothing.
+    /// </summary>
+    private void DiscardTraining(GameState gameState)
+    {
+        if (gameState.Trainer == nint.Zero)
+            return;
+
+        weightsStore.DestroyTrainer(gameState.Trainer);
+        gameState.Trainer = nint.Zero;
+    }
+
+    /// <summary>
+    /// Determines the trainable outcome of a finished game: the winning color and the reward
+    /// weight. Returns false when the game teaches nothing (balanced draw, forfeit, unfinished).
+    /// </summary>
+    private static bool TryDetermineOutcome(GameState gameState, out PieceColor winner, out double weight)
+    {
+        winner = PieceColor.White;
+        weight = 1.0;
+
+        if (gameState.IsCheckmate)
+        {
+            // The side to move is the mated one, so the winner is the other color.
+            winner = gameState.CurrentPlayer == PieceColor.White ? PieceColor.Black : PieceColor.White;
+            return true;
+        }
+
+        if (gameState.IsStalemate || gameState.IsThreefoldRepetition)
+        {
+            var (white, black) = MaterialCounts(gameState);
+
+            if (white == black)
+                return false;                 // a balanced draw carries no signal
+
+            winner = white < black ? PieceColor.White : PieceColor.Black;
+            weight = 0.5;
+            return true;
+        }
+
+        return false;                         // forfeit / unfinished
+    }
+
+    /// <summary>Total non-king material per side (P=1, N=B=3, R=5, Q=9), for draw adjudication.</summary>
+    private static (int white, int black) MaterialCounts(GameState gameState)
+    {
+        int white = 0, black = 0;
+
+        for (int row = 0; row < 8; row++)
+            for (int col = 0; col < 8; col++)
+            {
+                var piece = gameState.Board[row, col];
+
+                if (piece is null)
+                    continue;
+
+                int value = piece.Type switch
+                {
+                    PieceType.Pawn => 1,
+                    PieceType.Knight => 3,
+                    PieceType.Bishop => 3,
+                    PieceType.Rook => 5,
+                    PieceType.Queen => 9,
+                    _ => 0
+                };
+
+                if (piece.Color == PieceColor.White)
+                    white += value;
+                else
+                    black += value;
+            }
+
+        return (white, black);
+    }
+}

JoshHeaps.Net/Services/Implementations/Stockfish.cs

@@ -100,11 +100,26 @@ public sealed class Stockfish : IChessEngine
             if (line == token) break;
     }
 
+    // If Stockfish doesn't exit on "quit" (crashed, zombie, ignores stdin close), don't hang
+    // here forever — that would block GameStore's removal task and leave the finished game
+    // stuck in the store, cluttering the watch page indefinitely.
+    private static readonly TimeSpan _exitTimeout = TimeSpan.FromSeconds(5);
+
     public async ValueTask DisposeAsync()
     {
         Send("quit");
         _stdin.Close();
-        await _p.WaitForExitAsync();
+
+        try
+        {
+            await _p.WaitForExitAsync().WaitAsync(_exitTimeout);
+        }
+        catch (TimeoutException)
+        {
+            if (!_p.HasExited)
+                _p.Kill(entireProcessTree: true);
+        }
+
         _p.Dispose();
     }
 }

JoshHeaps.Net/Services/Interfaces/IChessEngineFactory.cs

@@ -1,3 +1,5 @@
+using JoshHeaps.Net.Services.Implementations;
+
 namespace JoshHeaps.Net.Services.Interfaces;
 
 /// <summary>
@@ -6,9 +8,20 @@ namespace JoshHeaps.Net.Services.Interfaces;
 public interface IChessEngineFactory
 {
     /// <summary>
-    /// Creates a new engine instance for a single game. The caller owns and disposes it.
+    /// Creates a new engine instance for a single game using the configured default engine.
+    /// The caller owns and disposes it.
     /// </summary>
     /// <param name="skill">The desired playing strength / search depth.</param>
     /// <returns>A new, owned <see cref="IChessEngine"/>.</returns>
     IChessEngine Create(int skill);
+
+    /// <summary>
+    /// Creates a new engine instance for a single game using an explicitly chosen engine
+    /// (e.g. for picking a different engine per side in a CPU-vs-CPU game). The caller owns
+    /// and disposes it.
+    /// </summary>
+    /// <param name="skill">The desired playing strength / search depth.</param>
+    /// <param name="kind">The engine implementation to create.</param>
+    /// <returns>A new, owned <see cref="IChessEngine"/>.</returns>
+    IChessEngine Create(int skill, ChessEngineKind kind);
 }

JoshHeaps.Net/Services/Interfaces/IComputerMoveOrchestrator.cs

@@ -3,16 +3,24 @@ using JoshHeaps.Net.Models;
 namespace JoshHeaps.Net.Services.Interfaces;
 
 /// <summary>
-/// Drives a computer move: asks the engine for a move, applies it through the rules
-/// service, and broadcasts the result to the game's clients.
+/// Drives a computer move: asks the side-to-move's engine for a move, applies it through
+/// the rules service, and broadcasts the result to the game's clients.
 /// </summary>
 public interface IComputerMoveOrchestrator
 {
     /// <summary>
-    /// Has the engine pick a move for the current position, applies it, and broadcasts it.
+    /// Has the side-to-move's engine pick a move for the current position, applies it, and
+    /// broadcasts it. The engine is taken from the game's per-side computer assignments.
     /// </summary>
     /// <param name="state">The game to play a move in.</param>
-    /// <param name="engine">The engine that selects the move.</param>
     /// <returns>The applied move and its result.</returns>
-    Task<(MoveDto move, MoveResultDto result)> PlayAsync(GameState state, IChessEngine engine);
+    Task<(MoveDto move, MoveResultDto result)> PlayAsync(GameState state);
+
+    /// <summary>
+    /// Plays a uniformly-random legal move for the side to move (no engine), applying and
+    /// broadcasting it. Used to randomize the opening of training games so self-play and
+    /// engine-vs-engine games don't replay the same line every time.
+    /// </summary>
+    /// <param name="state">The game to play a random move in.</param>
+    Task PlayRandomMoveAsync(GameState state);
 }

JoshHeaps.Net/Services/Interfaces/IGameStore.cs

@@ -0,0 +1,29 @@
+using JoshHeaps.Net.Models;
+
+namespace JoshHeaps.Net.Services.Interfaces;
+
+/// <summary>
+/// Process-wide registry of in-memory games and their cleanup lifecycle. Shared by the HTTP
+/// controller (human and single-computer games) and the self-play coordinator (CPU-vs-CPU and
+/// auto-training games), so every game is reachable from one place for lookup and spectating.
+/// </summary>
+public interface IGameStore
+{
+    /// <summary>Add (or replace) a game in the registry.</summary>
+    void Add(GameState game);
+
+    /// <summary>Look a game up by id.</summary>
+    bool TryGet(Guid id, out GameState game);
+
+    /// <summary>Whether a game with this id is still in the registry.</summary>
+    bool Contains(Guid id);
+
+    /// <summary>Snapshot of all games currently in the registry.</summary>
+    IReadOnlyCollection<GameState> All { get; }
+
+    /// <summary>
+    /// Schedule removal of a game after <paramref name="delay"/>, cancelling any prior schedule
+    /// for it. On removal the game's engines are disposed and any training accumulator freed.
+    /// </summary>
+    void ScheduleRemove(Guid id, TimeSpan delay);
+}

JoshHeaps.Net/Services/Interfaces/ILearnedWeightsStore.cs

@@ -0,0 +1,33 @@
+using JoshHeaps.Net.Models;
+
+namespace JoshHeaps.Net.Services.Interfaces;
+
+/// <summary>
+/// Thin managed facade over the native learned-weights model. The weights, all feature
+/// computation, per-game accumulation, the update rule, and persistence live in the native
+/// engine; this just points it at the weights file, hands out per-game trainers, and reads
+/// the table back for visualization.
+/// </summary>
+public interface ILearnedWeightsStore
+{
+    /// <summary>Absolute path to the weights file the native engine loads and saves.</summary>
+    string WeightsFilePath { get; }
+
+    /// <summary>A copy of the current weights (midgame/endgame tables + feature weights).</summary>
+    LearnedWeightsSnapshot Snapshot();
+
+    /// <summary>Creates a per-game training accumulator. The caller owns it (see <see cref="DestroyTrainer"/>).</summary>
+    nint CreateTrainer();
+
+    /// <summary>Records one played position (post-move FEN) into a trainer.</summary>
+    void Record(nint trainer, string fen);
+
+    /// <summary>
+    /// Applies a finished game's outcome to the global weights (and saves): rewards the
+    /// winner's squares/features, punishes the loser's, scaled by <paramref name="weight"/>.
+    /// </summary>
+    void ApplyResult(nint trainer, PieceColor winner, double weight);
+
+    /// <summary>Frees a trainer. Safe to call with <see cref="nint.Zero"/>.</summary>
+    void DestroyTrainer(nint trainer);
+}

JoshHeaps.Net/Services/Interfaces/ISelfPlayCoordinator.cs

@@ -0,0 +1,23 @@
+using JoshHeaps.Net.Services.Implementations;
+
+namespace JoshHeaps.Net.Services.Interfaces;
+
+/// <summary>Per-side engine and strength for a CPU-vs-CPU game.</summary>
+public sealed record SelfPlayConfig(
+    ChessEngineKind WhiteKind, int WhiteSkill,
+    ChessEngineKind BlackKind, int BlackSkill);
+
+/// <summary>
+/// Creates and runs CPU-vs-CPU games to completion: randomized opening, move loop, and (when
+/// the learned engine plays) feeding the result back into the learned weights. Used by the
+/// spectator "watch" endpoint and by the auto-trainer.
+/// </summary>
+public interface ISelfPlayCoordinator
+{
+    /// <summary>
+    /// Create, register, and start running a self-play game. Returns immediately with the new
+    /// game's id and a task that completes when the game finishes (or is cancelled). Callers
+    /// that only need the id can ignore the task; the auto-trainer awaits it to start the next.
+    /// </summary>
+    (Guid GameId, Task Completion) StartGame(SelfPlayConfig config, CancellationToken cancellationToken = default);
+}

JoshHeaps.Net/wwwroot/css/casino/page.css

@@ -0,0 +1,126 @@
+body {
+    background: #1a1a1a;
+    min-height: 100vh;
+    margin: 0;
+    padding: 0;
+}
+
+.casino-container {
+    max-width: 1000px;
+    margin: 0 auto;
+    padding: 4rem 2rem;
+    text-align: center;
+}
+
+.casino-header {
+    color: #f5f5f5;
+    font-size: 2.5rem;
+    margin-bottom: 0.5rem;
+    font-weight: 300;
+    letter-spacing: 0.1em;
+}
+
+.casino-subtitle {
+    color: #a0a0a0;
+    font-size: 1rem;
+    margin-bottom: 4rem;
+    font-weight: 300;
+}
+
+.games-grid {
+    display: grid;
+    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
+    gap: 1.5rem;
+    margin: 3rem auto;
+    max-width: 900px;
+    padding: 0 1rem;
+}
+
+.game-card {
+    background: #2a2a2a;
+    border: 1px solid #3a3a3a;
+    border-radius: 4px;
+    padding: 2rem 1.5rem;
+    transition: all 0.3s ease;
+    cursor: pointer;
+    text-decoration: none;
+    color: inherit;
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+}
+
+.game-card:hover {
+    background: #2f2f2f;
+    border-color: #4a4a4a;
+    transform: translateY(-2px);
+}
+
+.game-card.disabled {
+    opacity: 0.4;
+    cursor: not-allowed;
+}
+
+.game-card.disabled:hover {
+    background: #2a2a2a;
+    border-color: #3a3a3a;
+    transform: none;
+}
+
+.game-icon {
+    font-size: 2.5rem;
+    margin-bottom: 1rem;
+    opacity: 0.9;
+}
+
+.game-title {
+    font-size: 1.2rem;
+    font-weight: 400;
+    color: #f5f5f5;
+    margin-bottom: 0.75rem;
+    letter-spacing: 0.05em;
+}
+
+.game-description {
+    font-size: 0.9rem;
+    color: #999;
+    line-height: 1.6;
+    font-weight: 300;
+}
+
+.coming-soon {
+    color: #666;
+    font-style: italic;
+    margin-top: 0.5rem;
+    font-size: 0.85rem;
+}
+
+.home-button {
+    margin-top: 4rem;
+    padding: 0.75rem 1.5rem;
+    font-size: 0.9rem;
+    background: transparent;
+    color: #f5f5f5;
+    border: 1px solid #3a3a3a;
+    border-radius: 4px;
+    cursor: pointer;
+    transition: all 0.3s ease;
+    text-decoration: none;
+    display: inline-block;
+    letter-spacing: 0.05em;
+}
+
+.home-button:hover {
+    background: #2a2a2a;
+    border-color: #4a4a4a;
+}
+
+@media (max-width: 768px) {
+    .casino-header {
+        font-size: 2rem;
+    }
+
+    .games-grid {
+        grid-template-columns: 1fr;
+    }
+}

JoshHeaps.Net/wwwroot/css/casino/quicksplit.css

@@ -0,0 +1,541 @@
+/* Quick Split is phone-first: sized for one thumb at the table, then allowed to
+   breathe on a laptop. Palette matches the dealer table so the two read as one tool. */
+
+body {
+    background: radial-gradient(ellipse at 50% -10%, #1c1c1c 0%, #101010 55%, #0a0a0a 100%);
+    min-height: 100vh;
+    margin: 0;
+    color: #e6e6e6;
+    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
+}
+
+/* Same touch handling as the dealer table — see the note there. This page is the one
+   a dealer opens mid-hand to chop a pot, so the ~300ms the browser spends deciding
+   whether a tap was a double-tap-to-zoom is the last thing it needs. */
+button,
+[role="button"],
+input,
+select,
+textarea,
+a {
+    touch-action: manipulation;
+}
+
+button,
+[role="button"],
+input,
+select,
+textarea,
+a {
+    -webkit-tap-highlight-color: transparent;
+}
+
+/* Not on the fields — a dealer typing a pot amount still needs to select it. */
+button,
+[role="button"] {
+    -webkit-user-select: none;
+    user-select: none;
+}
+
+.clearPotBtn:active:not(:disabled),
+.choiceChip:active:not(:disabled),
+.stepBtn:active:not(:disabled),
+.splitBtn:active:not(:disabled),
+.splitBtnGhost:active:not(:disabled),
+.unevenFoldBtn:active:not(:disabled),
+.unevenRemoveBtn:active:not(:disabled) {
+    transform: translateY(1px);
+    filter: brightness(1.25);
+    transition-duration: 0.04s;
+}
+
+@media (prefers-reduced-motion: reduce) {
+    .clearPotBtn:active:not(:disabled),
+    .choiceChip:active:not(:disabled),
+    .stepBtn:active:not(:disabled),
+    .splitBtn:active:not(:disabled),
+    .splitBtnGhost:active:not(:disabled),
+    .unevenFoldBtn:active:not(:disabled),
+    .unevenRemoveBtn:active:not(:disabled) {
+        transform: none;
+    }
+}
+
+#splitApp {
+    max-width: 480px;
+    margin: 0 auto;
+    padding: 1.25rem 1rem 3rem;
+}
+
+/* ---------- Header ---------- */
+
+#splitHeader h1 {
+    margin: 0;
+    font-size: 1.5rem;
+    font-weight: 300;
+    letter-spacing: 0.04em;
+    color: #f5f5f5;
+    position: relative;
+    display: inline-block;
+    padding-bottom: 0.35rem;
+}
+
+#splitHeader h1::after {
+    content: "";
+    position: absolute;
+    left: 0;
+    bottom: 0;
+    width: 36px;
+    height: 3px;
+    border-radius: 2px;
+    background: linear-gradient(90deg, #d8b46a, #a9782f);
+}
+
+.splitSubtitle {
+    margin: 0.35rem 0 1.25rem;
+    color: #8f8f8f;
+    font-size: 0.85rem;
+}
+
+/* ---------- Mode toggle ---------- */
+
+#modeToggle {
+    margin-bottom: 1.1rem;
+}
+
+/* ---------- Uneven amounts ---------- */
+
+#unevenRows {
+    display: flex;
+    flex-direction: column;
+    gap: 0.45rem;
+    margin-bottom: 0.6rem;
+}
+
+.unevenRow {
+    display: flex;
+    align-items: center;
+    gap: 0.45rem;
+}
+
+.unevenRowLabel {
+    flex: none;
+    width: 2rem;
+    color: #8f8f8f;
+    font-size: 0.8rem;
+    font-weight: 600;
+}
+
+.unevenAmountWrap {
+    flex: 1;
+    min-width: 0;
+    display: flex;
+    align-items: center;
+    gap: 0.3rem;
+    background: #141414;
+    border: 1px solid #3a3a3a;
+    border-radius: 10px;
+    padding: 0 0.6rem;
+}
+
+.unevenAmountWrap:focus-within {
+    border-color: #d8b46a;
+}
+
+.unevenCurrency {
+    color: #777;
+}
+
+.unevenAmount {
+    flex: 1;
+    min-width: 0;
+    background: none;
+    border: none;
+    outline: none;
+    color: #f2f2f2;
+    font-family: inherit;
+    font-size: 16px;
+    font-variant-numeric: tabular-nums;
+    padding: 0.6rem 0;
+}
+
+.unevenFoldBtn {
+    flex: none;
+    min-height: 44px;
+    padding: 0 0.6rem;
+    border-radius: 9px;
+    border: 1px solid #3a3a3a;
+    background: #232323;
+    color: #8f8f8f;
+    font-family: inherit;
+    font-size: 0.72rem;
+    cursor: pointer;
+}
+
+.unevenFoldBtn.selected {
+    background: linear-gradient(180deg, #3d1f1f, #2c1515);
+    border-color: #5b2626;
+    color: #ffd6d6;
+}
+
+.unevenRemoveBtn {
+    flex: none;
+    width: 30px;
+    height: 44px;
+    border: none;
+    background: none;
+    color: #6a6a6a;
+    font-size: 0.85rem;
+    cursor: pointer;
+}
+
+.unevenRemoveBtn:disabled {
+    opacity: 0.3;
+    cursor: not-allowed;
+}
+
+#unevenResult {
+    background: linear-gradient(160deg, #1f2a21, #161c17);
+    border: 1px solid #2c3a2f;
+    border-radius: 14px;
+    padding: 0.9rem 1rem;
+    margin-bottom: 1.5rem;
+}
+
+#unevenResult[hidden] {
+    display: none;
+}
+
+.unevenPot {
+    display: flex;
+    align-items: baseline;
+    gap: 0.6rem;
+    padding: 0.3rem 0;
+    font-size: 0.85rem;
+}
+
+.unevenPot + .unevenPot {
+    border-top: 1px solid rgba(255, 255, 255, 0.06);
+}
+
+.unevenPotLabel {
+    flex: none;
+    color: #d8b46a;
+    font-weight: 600;
+}
+
+.unevenPotAmount {
+    flex: none;
+    color: #f2f2f2;
+    font-weight: 600;
+    font-variant-numeric: tabular-nums;
+}
+
+.unevenPotWho {
+    flex: 1;
+    min-width: 0;
+    text-align: right;
+    color: #9a9a9a;
+    font-size: 0.78rem;
+}
+
+.unevenPotReturn .unevenPotLabel,
+.unevenPotReturn .unevenPotAmount {
+    color: #9a9a9a;
+    font-weight: 500;
+}
+
+.unevenPotTotal {
+    margin-top: 0.15rem;
+    border-top: 1px solid rgba(255, 255, 255, 0.14) !important;
+}
+
+.unevenPotTotal .unevenPotLabel {
+    color: #8f9d92;
+    font-weight: 500;
+}
+
+.unevenEmpty {
+    margin: 0;
+    color: #8f9d92;
+    font-size: 0.82rem;
+    line-height: 1.45;
+}
+
+/* ---------- The answer ---------- */
+
+#splitResult {
+    background: linear-gradient(160deg, #1f2a21, #161c17);
+    border: 1px solid #2c3a2f;
+    border-radius: 14px;
+    padding: 1.4rem 1.1rem;
+    text-align: center;
+    margin-bottom: 1.5rem;
+    transition: border-color 0.2s ease, box-shadow 0.2s ease;
+}
+
+#splitResult.hasAmount {
+    border-color: #3c6b46;
+    box-shadow: 0 0 0 1px rgba(78, 201, 122, 0.08), 0 6px 20px rgba(0, 0, 0, 0.35);
+}
+
+#splitResultLabel {
+    color: #8f9d92;
+    font-size: 0.78rem;
+    letter-spacing: 0.06em;
+    text-transform: uppercase;
+}
+
+#splitResultAmount {
+    margin-top: 0.35rem;
+    font-size: clamp(2.6rem, 14vw, 3.4rem);
+    font-weight: 600;
+    line-height: 1.05;
+    color: #f2f2f2;
+    font-variant-numeric: tabular-nums;
+    letter-spacing: -0.01em;
+}
+
+#splitResult.hasAmount #splitResultAmount {
+    color: #7ee2a0;
+}
+
+#splitOddNote {
+    margin-top: 0.7rem;
+    color: #d8b46a;
+    font-size: 0.85rem;
+    line-height: 1.45;
+}
+
+#splitDustNote {
+    margin-top: 0.5rem;
+    color: #e0a1a1;
+    font-size: 0.8rem;
+    line-height: 1.4;
+}
+
+/* ---------- Inputs ---------- */
+
+.splitField {
+    display: block;
+    margin-bottom: 1.35rem;
+}
+
+/* A `display` declaration outranks the browser's own [hidden] rule, so anything
+   given one has to opt back out explicitly or toggling `hidden` does nothing. */
+[hidden] {
+    display: none !important;
+}
+
+.splitLabel {
+    display: block;
+    margin-bottom: 0.5rem;
+    color: #9a9a9a;
+    font-size: 0.75rem;
+    letter-spacing: 0.06em;
+    text-transform: uppercase;
+}
+
+.potInputWrap {
+    display: flex;
+    align-items: center;
+    gap: 0.4rem;
+    background: #141414;
+    border: 1px solid #3a3a3a;
+    border-radius: 12px;
+    padding: 0.2rem 0.75rem;
+    transition: border-color 0.15s ease, box-shadow 0.15s ease;
+}
+
+.potInputWrap:focus-within {
+    border-color: #d8b46a;
+    box-shadow: 0 0 0 3px rgba(216, 180, 106, 0.12);
+}
+
+.potCurrency {
+    color: #777;
+    font-size: 1.6rem;
+    font-weight: 300;
+}
+
+#potInput {
+    flex: 1;
+    min-width: 0;
+    background: none;
+    border: none;
+    outline: none;
+    color: #f2f2f2;
+    font-size: 2rem;
+    font-weight: 500;
+    font-variant-numeric: tabular-nums;
+    padding: 0.55rem 0;
+    font-family: inherit;
+}
+
+#potInput::placeholder {
+    color: #4a4a4a;
+}
+
+.clearPotBtn {
+    flex: none;
+    width: 34px;
+    height: 34px;
+    border-radius: 50%;
+    border: none;
+    background: #262626;
+    color: #999;
+    font-size: 0.85rem;
+    cursor: pointer;
+}
+
+@media (hover: hover) {
+    .clearPotBtn:hover {
+        background: #333;
+        color: #ddd;
+    }
+}
+
+/* ---------- Tap targets ---------- */
+
+.chipRow {
+    display: flex;
+    flex-wrap: wrap;
+    gap: 0.5rem;
+}
+
+.choiceChip {
+    flex: 1 1 auto;
+    min-width: 58px;
+    min-height: 52px;
+    padding: 0.5rem 0.7rem;
+    background: linear-gradient(180deg, #2e2e2e, #232323);
+    border: 1px solid #3a3a3a;
+    border-radius: 11px;
+    color: #ddd;
+    font-size: 1rem;
+    font-family: inherit;
+    cursor: pointer;
+    transition: all 0.15s ease;
+}
+
+@media (hover: hover) {
+    .choiceChip:hover {
+        border-color: #4a4a4a;
+        background: linear-gradient(180deg, #383838, #2a2a2a);
+    }
+}
+
+.choiceChip.selected {
+    background: linear-gradient(180deg, #3a2f18, #241d0f);
+    border-color: #d8b46a;
+    color: #f0d9a8;
+    font-weight: 600;
+}
+
+.waysStepper {
+    display: flex;
+    align-items: center;
+    gap: 0.35rem;
+    flex: 1 1 auto;
+    min-width: 150px;
+    background: #191919;
+    border: 1px solid #333;
+    border-radius: 11px;
+    padding: 0.2rem 0.4rem;
+}
+
+.stepBtn {
+    width: 40px;
+    height: 44px;
+    border: none;
+    border-radius: 8px;
+    background: #262626;
+    color: #ddd;
+    font-size: 1.25rem;
+    line-height: 1;
+    font-family: inherit;
+    cursor: pointer;
+}
+
+@media (hover: hover) {
+    .stepBtn:hover {
+        background: #333;
+    }
+}
+
+.waysReadout {
+    flex: 1;
+    text-align: center;
+    color: #999;
+    font-size: 0.8rem;
+    font-variant-numeric: tabular-nums;
+}
+
+/* ---------- Footer actions ---------- */
+
+#splitActions {
+    display: flex;
+    gap: 0.6rem;
+    margin-top: 1.75rem;
+}
+
+.splitBtn {
+    flex: 1;
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    min-height: 48px;
+    padding: 0.6rem 0.9rem;
+    border-radius: 10px;
+    border: 1px solid #3a3a3a;
+    background: linear-gradient(180deg, #2e2e2e, #232323);
+    color: #ddd;
+    font-size: 0.9rem;
+    font-family: inherit;
+    text-decoration: none;
+    cursor: pointer;
+    transition: all 0.15s ease;
+}
+
+@media (hover: hover) {
+    .splitBtn:hover {
+        border-color: #4a4a4a;
+        background: linear-gradient(180deg, #383838, #2a2a2a);
+    }
+}
+
+.splitBtnGhost {
+    background: transparent;
+}
+
+.splitFootnote {
+    margin-top: 1.5rem;
+    color: #6f6f6f;
+    font-size: 0.78rem;
+    line-height: 1.5;
+    text-align: center;
+}
+
+/* This footnote names a control the dealer is being told to reach for, so the name
+   itself has to be readable — it was 3.39:1 at its worst, inheriting the muted grey
+   the surrounding sentence is deliberately set in. Emphasised text carrying the
+   instruction gets its own colour rather than the aside's. */
+.splitFootnote strong {
+    color: #a8a8a8;
+    font-weight: 600;
+}
+
+.splitFootnote a {
+    color: #a9782f;
+}
+
+/* Roomier once there's a real screen to work with. */
+@media (min-width: 700px) {
+    #splitApp {
+        padding-top: 2.5rem;
+    }
+
+    #splitHeader h1 {
+        font-size: 1.8rem;
+    }
+}

JoshHeaps.Net/wwwroot/css/chess/game.css

@@ -1,12 +1,4 @@
-#boardContainer {
-    position: relative;
-    width: fit-content;
-    margin: 2vw auto;
-}
-
-#chessBoard {
-    width: 60vw;
-    height: 60vw;
+#chessBoard {
     display: grid;
     grid-template-columns: repeat(8, 1fr);
     grid-template-rows: repeat(8, 1fr);
@@ -165,6 +157,47 @@
     pointer-events: none; /* ensures img doesn't steal the click */
 }
 
+#colorModal {
+    position: absolute;
+    top: 50%;
+    left: 50%;
+    transform: translate(-50%, -50%);
+    background-color: #1e1e1e;
+    padding: 20px;
+    border-radius: 10px;
+    box-shadow: 0 0 20px rgba(0,0,0,0.6);
+    color: white;
+    z-index: 1000;
+    text-align: center;
+}
+
+#colorModal p {
+    margin-bottom: 15px;
+    font-size: 18px;
+    font-weight: bold;
+}
+
+#colorButtonContainer {
+    display: flex;
+    gap: 10px;
+    justify-content: center;
+}
+
+#colorButtonContainer button {
+    background-color: #2c2c2c;
+    border: none;
+    padding: 10px 18px;
+    border-radius: 8px;
+    cursor: pointer;
+    transition: transform 0.2s ease;
+    color: white;
+}
+
+#colorButtonContainer button:hover {
+    transform: scale(1.1);
+    background-color: #3a3a3a;
+}
+
 .chessSquare .coordinate-label {
     position: absolute;
     font-size: 1.2vw;

JoshHeaps.Net/wwwroot/css/chess/site.css

@@ -1,159 +1,429 @@
-html, body {
-    background-color: #2b2c30;
-    color: #d6d6d6;
-    cursor: default;
+:root {
+    --bg: #2b2c30;
+    --panel: #21232a;
+    --panel-row: rgba(255, 255, 255, 0.035);
+    --bar: #1e2026;
+    --accent: #8cd5ed;
+    --accent-ink: #10222a;
+    --text: #d6d6d6;
+    --muted: #8b8f99;
+    --line: #34373f;
+    --bar-h: clamp(34px, 5.5vh, 50px);
+    --radius: 12px;
+    --font: 'Outfit', system-ui, -apple-system, Segoe UI, sans-serif;
+}
+
+html, body {
     height: 100%;
     margin: 0;
+    background: var(--bg);
+    color: var(--text);
+    font-family: var(--font);
+    cursor: default;
+    /* The chess page is a fixed, single-screen app: never scroll. */
+    overflow: hidden;
 }
 
-#startGameBtn {
-    background-color: #8cd5ed;
-    color: #262626;
-    border-radius: 30px;
-    border: 0px;
-    cursor: pointer;
-    order: 1;
-    padding: 2vh;
-    margin: 2vh;
+main {
+    height: 100%;
 }
 
-#startCPUGame {
-    background-color: #8cd5ed;
-    color: #262626;
-    border-radius: 30px;
-    border: 0px;
-    cursor: pointer;
-    order: 1;
-    padding: 2vh;
-    margin: 2vh;
-}
-
-#copyPgnBtn {
-    background-color: #8cd5ed;
-    color: #262626;
-    border-radius: 30px;
-    border: 0px;
-    cursor: pointer;
-    order: 1;
-    padding: 2vh;
-    margin: 2vh;
-}
-
-#watchLink {
-    color: #8cd5ed;
-    text-decoration: none;
-    margin: 2vh;
-    order: 2;
-}
-
-#watchLink:hover {
-    text-decoration: underline;
-}
+/* ---- Layout ------------------------------------------------------------ */
 
+/* Portrait / narrow: board on top, panel stacked below. */
 #chessContainer {
+    height: 100vh;
+    height: 100dvh;
+    box-sizing: border-box;
     display: flex;
     flex-direction: column;
     align-items: center;
-    justify-content: space-evenly;
-    height: 100vh;
-    box-sizing: border-box;
-    padding: 5vw;
+    gap: clamp(8px, 1.6vh, 16px);
+    padding: clamp(10px, 2vh, 20px);
+    overflow: hidden;
+}
+
+#boardArea {
+    display: flex;
+    flex-direction: column;
+    gap: 6px;
+    flex: 0 0 auto;
+    width: min(94vw, 56vh);
 }
 
 #chessBoard {
-    aspect-ratio: 1 / 1;
-    width: 90vw; /* use the smaller of width or height */
+    width: 100%;
     height: auto;
-    max-height: 90vw;
+    aspect-ratio: 1 / 1;
+    border-radius: 6px;
+    overflow: hidden;
+    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.45);
 }
 
-#boardContainer {
-    align-content: center;
-    flex-grow: 1;
-}
-
-.sideContent {
+#gamePanel {
+    width: min(94vw, 56vh);
+    flex: 1 1 auto;
+    min-height: 0;
     display: flex;
     flex-direction: column;
-    align-content: center;
-    justify-content: center;
-    text-align: center;
+    background: var(--panel);
+    border-radius: var(--radius);
+    overflow: hidden;
+    box-shadow: 0 6px 24px rgba(0, 0, 0, 0.35);
 }
 
-#textContainer {
-    flex-direction: column;
-    order: -1;
-    flex-shrink: 1;
-    font-size: large;
-    margin: 5vw;
-}
-
-#buttonContainer {
-    flex-grow: 3;
-}
-
-/* Put UI to left/right when screen is short */
+/* Landscape / wide: board left, game panel right (chess.com style). */
 @media (min-aspect-ratio: 1/1) {
     #chessContainer {
-        display: grid;
-        grid-template-columns: auto, auto;
-        grid-template-rows: auto, auto;
-        align-items: center;
         flex-direction: row;
+        align-items: center;
         justify-content: center;
-        align-items: center;
-        height: 100vh;
-        padding: 0;
+        gap: clamp(16px, 3vw, 48px);
+        padding: clamp(12px, 3vh, 28px);
     }
 
-    .sideContent {
-        display: flex;
-        flex-direction: column;
-        flex-grow: 1;
-        flex-shrink: 0;
-        align-items: center;
-        text-align: center;
-        padding: min(5vw, 5vh);
-    }
-
-    #boardContainer {
-        grid-row: 1 / span 2;
-        grid-column: 1;
-    }
-
-    #textContainer {
-        grid-row: 1;
-        grid-column: 2;
-        text-align: center;
-        font-size: x-large;
-    }
-
-    #buttonContainer {
-        grid-row: 2;
-        grid-column: 2;
-        text-align: left;
-        align-self: start;
-    }
-
-    #startGameBtn {
-        padding: 1vw;
-        font-size: large;
-    }
-
-    #startCPUGame {
-        padding: 1vw;
-        margin: 1vw;
-        font-size: large;
+    #boardArea {
+        width: auto;
+        height: 100%;
+        justify-content: center;
+        flex: 0 0 auto;
     }
 
     #chessBoard {
-        aspect-ratio: 1 / 1;
-        flex-shrink: 1;
-        width: min(90vh, 90vw);
-        max-height: 90vh;
+        width: min(72vh, 54vw);
+        height: min(72vh, 54vw);
     }
 
-    #difficultyButtonContainer {
-        grid-template-columns: repeat(10, 1fr);
+    .playerBar {
+        width: min(72vh, 54vw);
     }
-}
+
+    #gamePanel {
+        width: clamp(300px, 26vw, 380px);
+        height: min(86vh, 100%);
+        align-self: center;
+    }
+}
+
+/* ---- Player bars ------------------------------------------------------- */
+
+.playerBar {
+    display: flex;
+    align-items: center;
+    gap: 10px;
+    width: 100%;
+    box-sizing: border-box;
+    height: var(--bar-h);
+    padding: 0 12px;
+    background: var(--bar);
+    border-radius: 8px;
+}
+
+.playerDot {
+    width: 14px;
+    height: 14px;
+    border-radius: 50%;
+    flex: 0 0 auto;
+}
+
+.playerDot.white {
+    background: #ededed;
+    box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.4) inset;
+}
+
+.playerDot.black {
+    background: #2c2c2c;
+    box-shadow: 0 0 0 1px #565656 inset;
+}
+
+.playerName {
+    font-weight: 600;
+    white-space: nowrap;
+}
+
+.capturedTray {
+    display: flex;
+    flex-wrap: wrap;
+    align-items: center;
+    gap: 1px;
+    flex: 1;
+    min-width: 0;
+    overflow: hidden;
+}
+
+.capturedPiece {
+    height: clamp(15px, calc(var(--bar-h) * 0.58), 26px);
+    width: auto;
+    margin-right: -5px;
+}
+
+.advantage {
+    margin-left: auto;
+    font-weight: 700;
+    color: var(--accent);
+    white-space: nowrap;
+}
+
+/* ---- Game panel -------------------------------------------------------- */
+
+.panelHeader {
+    display: flex;
+    align-items: center;
+    gap: 10px;
+    padding: 14px 16px;
+    border-bottom: 1px solid var(--line);
+    flex: 0 0 auto;
+}
+
+.panelLogo {
+    font-size: 1.5rem;
+    color: var(--accent);
+    line-height: 1;
+}
+
+.panelHeader h1 {
+    margin: 0;
+    font-size: 1.25rem;
+    font-weight: 700;
+    letter-spacing: 0.01em;
+}
+
+#moveList {
+    flex: 1 1 auto;
+    min-height: 0;
+    overflow-y: auto;
+    padding: 6px 0;
+}
+
+.movePlaceholder {
+    margin: 0;
+    padding: 18px 16px;
+    color: var(--muted);
+    font-size: 0.95rem;
+}
+
+.moveRow {
+    display: grid;
+    grid-template-columns: 2.4em 1fr 1fr;
+    align-items: center;
+    gap: 6px;
+    padding: 4px 14px;
+    font-size: 0.98rem;
+}
+
+.moveRow:nth-child(odd) {
+    background: var(--panel-row);
+}
+
+.moveNum {
+    color: var(--muted);
+    font-variant-numeric: tabular-nums;
+}
+
+.moveSan {
+    padding: 2px 7px;
+    border-radius: 5px;
+}
+
+.moveSan.latest {
+    background: var(--accent);
+    color: var(--accent-ink);
+    font-weight: 600;
+}
+
+#statusLine {
+    flex: 0 0 auto;
+    padding: 12px 16px;
+    border-top: 1px solid var(--line);
+    color: var(--muted);
+    font-weight: 500;
+}
+
+#statusLine.alert {
+    color: var(--accent);
+    font-weight: 700;
+}
+
+#panelButtons {
+    flex: 0 0 auto;
+    display: flex;
+    flex-direction: column;
+    gap: 10px;
+    padding: 14px 16px 16px;
+    border-top: 1px solid var(--line);
+}
+
+.btn {
+    font-family: inherit;
+    font-weight: 600;
+    font-size: clamp(0.92rem, 1vw, 1.05rem);
+    border: 0;
+    border-radius: 8px;
+    padding: clamp(10px, 1.4vh, 14px) 16px;
+    cursor: pointer;
+    transition: transform 0.08s ease, filter 0.15s ease, background 0.15s ease;
+}
+
+.btn:active {
+    transform: translateY(1px);
+}
+
+.btn-primary {
+    background: var(--accent);
+    color: var(--accent-ink);
+}
+
+.btn-primary:hover {
+    filter: brightness(1.08);
+}
+
+.btn-secondary {
+    background: #363a44;
+    color: var(--text);
+}
+
+.btn-secondary:hover {
+    background: #424752;
+}
+
+.btn-ghost {
+    background: transparent;
+    color: var(--accent);
+    border: 1px solid var(--line);
+}
+
+.btn-ghost:hover {
+    background: #2a2e37;
+}
+
+#watchLink {
+    color: var(--muted);
+    text-decoration: none;
+    text-align: center;
+    font-size: 0.9rem;
+    margin-top: 2px;
+}
+
+#watchLink:hover {
+    color: var(--accent);
+}
+
+/* ---- Mobile chrome (hidden on desktop) --------------------------------- */
+
+.iconBtn {
+    background: transparent;
+    border: 0;
+    color: var(--text);
+    font-size: 1.7rem;
+    line-height: 1;
+    cursor: pointer;
+    padding: 0 4px;
+}
+
+.iconBtn:hover {
+    color: var(--accent);
+}
+
+#menuClose {
+    margin-left: auto;
+}
+
+/* Default (tablet/desktop): no mobile bar, menu button, or sheet chrome. */
+#mobileBar,
+#menuBackdrop,
+#menuClose {
+    display: none;
+}
+
+/* ---- Phone layout ------------------------------------------------------ */
+/* The full panel doesn't fit alongside a usable board on a phone, so we show
+   the board + a slim status/menu bar, and tuck the move list and secondary
+   actions into a slide-up sheet. The page itself still never scrolls. */
+@media (max-width: 640px) {
+    #chessContainer {
+        flex-direction: column;
+        justify-content: flex-start;
+        gap: 8px;
+        padding: 8px;
+    }
+
+    #boardArea {
+        width: min(94vw, 60vh);
+        flex: 0 0 auto;
+    }
+
+    .playerBar {
+        width: 100%;
+    }
+
+    /* Right rail becomes a hidden bottom sheet, revealed by the Menu button. */
+    #gamePanel {
+        display: none;
+        position: fixed;
+        left: 0;
+        right: 0;
+        bottom: 0;
+        top: auto;
+        width: 100%;
+        height: auto;
+        max-height: 85dvh;
+        border-radius: 16px 16px 0 0;
+        z-index: 60;
+        box-shadow: 0 -8px 30px rgba(0, 0, 0, 0.5);
+    }
+
+    body.menu-open #gamePanel {
+        display: flex;
+    }
+
+    /* The slim bar already shows status, so hide the sheet's inline copy. */
+    #gamePanel #statusLine {
+        display: none;
+    }
+
+    #menuClose {
+        display: block;
+    }
+
+    #menuBackdrop {
+        position: fixed;
+        inset: 0;
+        background: rgba(0, 0, 0, 0.55);
+        z-index: 55;
+    }
+
+    body.menu-open #menuBackdrop {
+        display: block;
+    }
+
+    #mobileBar {
+        display: flex;
+        align-items: center;
+        gap: 10px;
+        width: min(94vw, 60vh);
+        flex: 0 0 auto;
+        box-sizing: border-box;
+        background: var(--panel);
+        border-radius: 10px;
+        padding: 8px 10px;
+    }
+
+    #mobileStatus {
+        flex: 1;
+        min-width: 0;
+        color: var(--muted);
+        font-weight: 600;
+        white-space: nowrap;
+        overflow: hidden;
+        text-overflow: ellipsis;
+    }
+
+    #mobileStatus.alert {
+        color: var(--accent);
+    }
+
+    #mobileBar #menuToggle {
+        flex: 0 0 auto;
+        padding: 10px 20px;
+    }
+}

JoshHeaps.Net/wwwroot/css/chess/spectate.css

@@ -21,11 +21,27 @@ html, body {
     display: flex;
     align-items: center;
     justify-content: center;
-    gap: 0.5rem;
+    flex-wrap: wrap;
+    gap: 0.75rem;
     margin: 1rem 0;
 }
 
-#cpuDifficulty {
+.enginePicker {
+    display: flex;
+    align-items: center;
+    gap: 0.4rem;
+    border: 1px solid #444;
+    border-radius: 8px;
+    padding: 0.3rem 0.6rem 0.5rem;
+}
+
+.enginePicker legend {
+    color: #9a9a9a;
+    font-size: 0.8rem;
+    padding: 0 0.3rem;
+}
+
+#watchControls select {
     background-color: #1e1e1e;
     color: #d6d6d6;
     border: 1px solid #444;

JoshHeaps.Net/wwwroot/css/chess/weights.css

@@ -0,0 +1,187 @@
+body {
+    margin: 0;
+    background-color: #141414;
+    color: #d6d6d6;
+    font-family: "Segoe UI", system-ui, sans-serif;
+}
+
+#weightsHeader {
+    text-align: center;
+    padding: 1.5rem 1rem 0.5rem;
+}
+
+#weightsHeader h1 {
+    margin: 0 0 0.25rem;
+    font-size: 1.6rem;
+}
+
+#weightsStatus {
+    color: #9a9a9a;
+    margin: 0.25rem 0 1rem;
+}
+
+#weightsControls {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    gap: 1.25rem;
+    margin-bottom: 0.5rem;
+}
+
+.heatLegend {
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+    font-size: 0.8rem;
+    color: #9a9a9a;
+}
+
+.legendBar {
+    width: 120px;
+    height: 10px;
+    border-radius: 5px;
+    background: linear-gradient(to right, rgba(232, 74, 74, 1), #2a2a2a, rgba(74, 134, 232, 1));
+}
+
+#refreshWeights {
+    background-color: #8cd5ed;
+    color: #262626;
+    border: 0;
+    border-radius: 30px;
+    padding: 0.5rem 1.1rem;
+    cursor: pointer;
+}
+
+#refreshWeights:hover {
+    background-color: #a5e0f2;
+}
+
+#backToWatch {
+    display: inline-block;
+    margin-top: 0.5rem;
+    color: #8cd5ed;
+    text-decoration: none;
+}
+
+.weightsSection {
+    margin: 0 auto;
+    max-width: 1200px;
+    padding: 0.5rem 1rem;
+}
+
+.weightsSection h2 {
+    text-align: center;
+    font-size: 1.2rem;
+    margin: 1rem 0 0.25rem;
+}
+
+.sectionHint {
+    text-align: center;
+    color: #9a9a9a;
+    font-size: 0.8rem;
+    margin: 0 0 0.75rem;
+}
+
+.weightsGrid {
+    display: flex;
+    flex-wrap: wrap;
+    justify-content: center;
+    gap: 1.25rem;
+    padding: 0.5rem 0;
+}
+
+.featurePanel {
+    max-width: 520px;
+    margin: 0 auto;
+    display: flex;
+    flex-direction: column;
+    gap: 0.4rem;
+}
+
+.featureRow {
+    display: flex;
+    align-items: center;
+    gap: 0.6rem;
+}
+
+.featureLabel {
+    flex: 0 0 6.5rem;
+    font-size: 0.8rem;
+    color: #c8c8c8;
+    text-align: right;
+}
+
+.featureTrack {
+    flex: 1 1 auto;
+    height: 14px;
+    background-color: #232323;
+    border-radius: 7px;
+    overflow: hidden;
+}
+
+.featureBar {
+    height: 100%;
+    border-radius: 7px;
+    min-width: 2px;
+}
+
+.featureValue {
+    flex: 0 0 3rem;
+    font-size: 0.8rem;
+    color: #e8e8e8;
+    text-align: left;
+}
+
+.weightBoard {
+    background-color: #1c1c1c;
+    border: 1px solid #2e2e2e;
+    border-radius: 10px;
+    padding: 0.75rem;
+}
+
+.weightBoardHeader {
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+    margin-bottom: 0.5rem;
+    font-weight: 600;
+}
+
+.weightBoardIcon {
+    width: 22px;
+    height: 22px;
+}
+
+.weightRange {
+    margin-left: auto;
+    font-weight: 400;
+    font-size: 0.75rem;
+    color: #888;
+}
+
+.miniHeat {
+    display: grid;
+    grid-template-columns: 1.1rem repeat(8, 34px);
+}
+
+.heatSquare {
+    width: 34px;
+    height: 34px;
+    box-sizing: border-box;
+    border: 1px solid #2a2a2a;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    font-size: 0.62rem;
+    color: #f0f0f0;
+    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.8);
+}
+
+.heatLabel {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    padding: 2px 0;
+    font-size: 0.6rem;
+    color: #777;
+}

JoshHeaps.Net/wwwroot/js/ChessScripts/ChessAPI.js

@@ -4,8 +4,8 @@ const ChessAPI = {
         return await response.json();
     },
 
-    async createCPUGame(difficulty) {
-        const response = await fetch(`/api/chess/new/${difficulty}`);
+    async createCPUGame(difficulty, color = "random") {
+        const response = await fetch(`/api/chess/new/${difficulty}?color=${color}`);
         return await response.json();
     },
 
@@ -46,13 +46,15 @@ const ChessAPI = {
             throw new Error(message || "Invalid move or not your turn.");
         }
 
-        const result = await response.json();
+        // The move endpoint returns both the move result and the full resulting
+        // board state, so the caller can render without a follow-up fetch.
+        const data = await response.json();
 
-        if (!result.success) {
-            throw new Error(result.message || "Invalid move or not your turn.");
+        if (!data.result.success) {
+            throw new Error(data.result.message || "Invalid move or not your turn.");
         }
 
-        return result;
+        return data;
     },
 
     async handleMove(targetRow, targetCol) {
@@ -85,16 +87,14 @@ const ChessAPI = {
         GameState.setPreviousMove([GameState.selectedPiece.row, GameState.selectedPiece.col], [targetRow, targetCol]);
 
         try {
-            const moveResult = await this.makeMove(moveDto);
+            const { result, state } = await this.makeMove(moveDto);
 
-            const updatedGame = await this.getGameState(GameState.currentGameId);
-            ChessBoard.renderPieces(updatedGame.pieces);
+            ChessBoard.renderState(state);
 
             GameState.clearSelection();
             ChessInteractions.clearHighlights();
 
-            await ChessSignalR.notifyMoveMade(moveDto, moveResult);
-            this.alertGameStatusChange(moveResult);
+            this.alertGameStatusChange(result);
 
         } catch (error) {
             alert("❌ " + error.message);

JoshHeaps.Net/wwwroot/js/ChessScripts/ChessBoard.js

@@ -1,4 +1,91 @@
+// Material value per piece type, indexed by PieceType (0=Pawn .. 5=King).
+const PIECE_VALUES = [1, 5, 3, 3, 9, 0];
+
 const ChessBoard = {
+    // Render from a full game-state payload (the shape returned by the move/state
+    // endpoints and pushed over SignalR). Ignores state older than what's already
+    // shown, so a slow initial fetch can't clobber a move that arrived first.
+    renderState(state) {
+        if (!state || !GameState.shouldApply(state.version)) return;
+        this.renderPieces(state.pieces);
+        this.renderCapturedTrays(state.pieces, state.capturedPieces);
+        this.renderMoveList(state.sanHistory);
+        this.renderStatus(state);
+        GameState.setVersion(state.version);
+    },
+
+    // Two-column numbered move list (white move, black move), latest highlighted.
+    renderMoveList(sanHistory) {
+        const list = document.getElementById("moveList");
+        if (!list) return;
+
+        const san = sanHistory ?? [];
+
+        if (san.length === 0) {
+            list.innerHTML = '<p class="movePlaceholder">Moves will appear here once a game begins.</p>';
+            return;
+        }
+
+        list.innerHTML = "";
+
+        for (let i = 0; i < san.length; i += 2) {
+            const row = document.createElement("div");
+            row.className = "moveRow";
+
+            const num = document.createElement("span");
+            num.className = "moveNum";
+            num.textContent = `${i / 2 + 1}.`;
+            row.appendChild(num);
+
+            row.appendChild(this.moveCell(san[i], i === san.length - 1));
+
+            if (i + 1 < san.length)
+                row.appendChild(this.moveCell(san[i + 1], i + 1 === san.length - 1));
+
+            list.appendChild(row);
+        }
+
+        list.scrollTop = list.scrollHeight;
+    },
+
+    moveCell(san, isLatest) {
+        const cell = document.createElement("span");
+        cell.className = isLatest ? "moveSan latest" : "moveSan";
+        cell.textContent = san;
+        return cell;
+    },
+
+    renderStatus(state) {
+        let text;
+        let alert = false;
+
+        if (state.isCheckmate) {
+            const winner = state.currentPlayer === "White" ? "Black" : "White";
+            text = `Checkmate — ${winner} wins`;
+            alert = true;
+        } else if (state.isStalemate) {
+            text = "Draw — stalemate";
+            alert = true;
+        } else if (state.isThreefoldRepetition) {
+            text = "Draw — threefold repetition";
+            alert = true;
+        } else {
+            text = `${state.currentPlayer} to move`;
+            if (state.isCheck) {
+                text += " — check";
+                alert = true;
+            }
+        }
+
+        // Mirror to both the desktop panel status and the mobile bar status.
+        ["statusLine", "mobileStatus"].forEach(id => {
+            const el = document.getElementById(id);
+            if (!el) return;
+            el.textContent = text;
+            el.classList.toggle("alert", alert);
+        });
+    },
+
     renderPieces(pieces) {
         this.clearAllSquares();
         this.renderCoordinateLabels();
@@ -7,6 +94,48 @@ const ChessBoard = {
         this.highlightPreviousMove();
     },
 
+    // Show each side's captured pieces and the leading side's material advantage,
+    // arranged so the current player's tray sits below the board.
+    renderCapturedTrays(activePieces, capturedPieces) {
+        const captured = capturedPieces ?? [];
+
+        // A captured piece's color is the side that lost it, so White's haul is the
+        // captured Black pieces, and vice versa.
+        const whiteCaptured = captured.filter(p => p.color === 1);
+        const blackCaptured = captured.filter(p => p.color === 0);
+
+        // Net material from pieces still on the board, so promotions count correctly.
+        const advantage = (activePieces ?? []).reduce(
+            (sum, p) => sum + (p.color === 0 ? PIECE_VALUES[p.type] : -PIECE_VALUES[p.type]), 0);
+
+        const white = { captured: whiteCaptured, advantage: Math.max(advantage, 0) };
+        const black = { captured: blackCaptured, advantage: Math.max(-advantage, 0) };
+
+        const isWhite = GameState.currentPlayerIsWhite !== false;
+        this.fillCapturedTray("bottom", isWhite ? white : black);
+        this.fillCapturedTray("top", isWhite ? black : white);
+    },
+
+    fillCapturedTray(position, side) {
+        const tray = document.getElementById(`captured-${position}`);
+        const badge = document.getElementById(`advantage-${position}`);
+        if (!tray || !badge) return;
+
+        tray.innerHTML = "";
+        [...side.captured]
+            .sort((a, b) => PIECE_VALUES[a.type] - PIECE_VALUES[b.type])
+            .forEach(piece => {
+                const img = document.createElement("img");
+                img.src = ChessUtils.getPieceImageUrl(piece);
+                img.alt = piece.type;
+                img.className = "capturedPiece";
+                img.draggable = false;
+                tray.appendChild(img);
+            });
+
+        badge.textContent = side.advantage > 0 ? `+${side.advantage}` : "";
+    },
+
     clearAllSquares() {
         for (let i = 0; i < 64; i++) {
             const square = document.getElementById(`square-${i}`);

JoshHeaps.Net/wwwroot/js/ChessScripts/ChessModals.js

@@ -23,6 +23,16 @@ const ChessModals = {
                 resolve(difficulty);
             };
         });
+    },
+
+    promptColor() {
+        return new Promise(resolve => {
+            document.getElementById("colorModal").style.display = "block";
+            window.selectColor = (color) => {
+                document.getElementById("colorModal").style.display = "none";
+                resolve(color);
+            };
+        });
     }
 };
 

JoshHeaps.Net/wwwroot/js/ChessScripts/ChessSignalR.js

@@ -11,8 +11,8 @@ const ChessSignalR = {
             console.error("❌ SignalR connection closed:", err?.message);
         });
 
-        this.connection.on("ReceiveMoveUpdate", async (gameId, moveDto, moveResultDto) => {
-            await this.handleMoveUpdate(gameId, moveDto, moveResultDto);
+        this.connection.on("ReceiveMoveUpdate", async (gameId, moveDto, moveResultDto, state) => {
+            await this.handleMoveUpdate(gameId, moveDto, moveResultDto, state);
         });
 
         this.connection.on("ReceiveGameOver", async (gameId, winner, reason) => {
@@ -28,12 +28,14 @@ const ChessSignalR = {
         }
     },
 
-    async handleMoveUpdate(gameId, moveDto, moveResultDto) {
+    async handleMoveUpdate(gameId, moveDto, moveResultDto, state) {
         if (gameId !== GameState.currentGameId) return;
 
-        const gameState = await ChessAPI.getGameState(gameId);
+        // Drop the echo of our own move and any out-of-order delivery.
+        if (!GameState.shouldApply(state?.version)) return;
+
         GameState.setPreviousMove([moveDto.sourceRow, moveDto.sourceCol], [moveDto.targetRow, moveDto.targetCol]);
-        ChessBoard.renderPieces(gameState.pieces);
+        ChessBoard.renderState(state);
 
         ChessAPI.alertGameStatusChange(moveResultDto);
     },
@@ -50,12 +52,6 @@ const ChessSignalR = {
         await this.leaveGame();
     },
 
-    async notifyMoveMade(moveDto, moveResult) {
-        if (this.connection) {
-            await this.connection.invoke("MoveMade", GameState.currentGameId, moveDto, moveResult);
-        }
-    },
-
     async leaveGame() {
         if (this.connection) {
             await this.connection.invoke("LeaveWebsocketGroup", GameState.currentGameId);

JoshHeaps.Net/wwwroot/js/ChessScripts/GameState.js

@@ -6,6 +6,10 @@ const GameState = {
     legalMoves: [],
     previousMoveStart: null,
     previousMoveEnd: null,
+    // Highest ply (move count) already rendered. Lets us ignore stale or
+    // already-applied updates that arrive out of order, including the echo
+    // of our own move.
+    lastVersion: -1,
 
     reset() {
         this.currentGameId = null;
@@ -15,12 +19,22 @@ const GameState = {
         this.legalMoves = [];
         this.previousMoveStart = null;
         this.previousMoveEnd = null;
+        this.lastVersion = -1;
+    },
+
+    shouldApply(version) {
+        return typeof version !== "number" || version > this.lastVersion;
+    },
+
+    setVersion(version) {
+        if (typeof version === "number") this.lastVersion = version;
     },
 
     setGameInfo(gameId, playerId, isWhite) {
         this.currentGameId = gameId;
         this.currentPlayerId = playerId;
         this.currentPlayerIsWhite = isWhite;
+        this.lastVersion = -1;
     },
 
     setSelectedPiece(piece) {

JoshHeaps.Net/wwwroot/js/ChessScripts/Spectate.js

@@ -11,8 +11,8 @@ const Spectate = {
             .configureLogging(signalR.LogLevel.Warning)
             .build();
 
-        this.connection.on("ReceiveMoveUpdate", (gameId, moveDto) =>
-            this.handleMoveUpdate(gameId, moveDto));
+        this.connection.on("ReceiveMoveUpdate", (gameId, moveDto, _moveResult, state) =>
+            this.handleMoveUpdate(gameId, moveDto, state));
 
         this.connection.on("ReceiveGameOver", (gameId) => this.removeGame(gameId));
 
@@ -23,14 +23,50 @@ const Spectate = {
         }
 
         await this.refreshGames();
+        await this.loadAutoTrainCount();
         setInterval(() => this.refreshGames(), 5000);
     },
 
-    async startCpuGame() {
-        const difficulty = document.getElementById("cpuDifficulty").value;
+    // Auto-training runs server-side; show its target count and let it be changed here.
+    async loadAutoTrainCount() {
+        const input = document.getElementById("autoTrainCount");
+        if (!input) return;
 
         try {
-            await fetch(`/api/chess/watch/cpu/${difficulty}`);
+            const response = await fetch("/api/chess/autotrain");
+            const data = await response.json();
+            input.max = data.max;
+            // Don't clobber the value while the user is editing it.
+            if (document.activeElement !== input)
+                input.value = data.count;
+        } catch {
+            // Leave the control as-is if auto-training status can't be read.
+        }
+    },
+
+    async setAutoTrainCount() {
+        const input = document.getElementById("autoTrainCount");
+        const count = Math.max(0, parseInt(input.value, 10) || 0);
+
+        try {
+            const response = await fetch(`/api/chess/autotrain?count=${count}`, { method: "POST" });
+            const data = await response.json();
+            input.value = data.count;
+        } catch (err) {
+            console.error("❌ Could not set the auto-training game count.", err);
+        }
+    },
+
+    async startCpuGame() {
+        const params = new URLSearchParams({
+            whiteEngine: document.getElementById("whiteEngine").value,
+            whiteSkill: document.getElementById("whiteSkill").value,
+            blackEngine: document.getElementById("blackEngine").value,
+            blackSkill: document.getElementById("blackSkill").value
+        });
+
+        try {
+            await fetch(`/api/chess/watch/cpu?${params}`);
             await this.refreshGames();
         } catch (err) {
             console.error("❌ Could not start CPU vs CPU game.", err);
@@ -68,7 +104,9 @@ const Spectate = {
     async addGame(game) {
         this.games.set(game.gameId, {
             isVsComputer: game.isVsComputer,
-            isComputerVsComputer: game.isComputerVsComputer
+            isComputerVsComputer: game.isComputerVsComputer,
+            whiteEngine: game.whiteEngine,
+            blackEngine: game.blackEngine
         });
 
         const card = document.createElement("div");
@@ -117,7 +155,10 @@ const Spectate = {
 
         if (!response.ok) return;
 
-        const state = await response.json();
+        this.renderFromState(gameId, await response.json());
+    },
+
+    renderFromState(gameId, state) {
         const result = this.resultTextFromState(state);
         const stored = this.games.get(gameId);
 
@@ -128,10 +169,13 @@ const Spectate = {
         this.setResult(gameId, result);
     },
 
-    async handleMoveUpdate(gameId, moveDto) {
+    async handleMoveUpdate(gameId, moveDto, state) {
         if (!this.games.has(gameId)) return;
 
-        await this.renderGame(gameId);
+        // Render from the pushed state; fall back to a fetch only if it's missing.
+        if (state) this.renderFromState(gameId, state);
+        else await this.renderGame(gameId);
+
         this.highlightMove(gameId, moveDto);
     },
 
@@ -177,11 +221,21 @@ const Spectate = {
     },
 
     gameLabel(stored) {
-        if (stored.isComputerVsComputer) return "CPU vs CPU";
+        if (stored.isComputerVsComputer)
+            return `${this.engineName(stored.whiteEngine)} (W) vs ${this.engineName(stored.blackEngine)} (B)`;
         if (stored.isVsComputer) return "Vs CPU";
         return "Player vs Player";
     },
 
+    engineName(kind) {
+        switch (kind) {
+            case "CustomLearned": return "Learned";
+            case "Custom": return "Custom";
+            case "Stockfish": return "Stockfish";
+            default: return kind || "CPU";
+        }
+    },
+
     headerText(stored, currentPlayer, moveCount, isCheck) {
         if (stored.result)
             return `${this.gameLabel(stored)} · move ${moveCount} · final`;

JoshHeaps.Net/wwwroot/js/ChessScripts/Weights.js

@@ -0,0 +1,158 @@
+const Weights = {
+    async init() {
+        await this.refresh();
+    },
+
+    async refresh() {
+        let data;
+
+        try {
+            const response = await fetch("/api/chess/weights");
+            data = await response.json();
+        } catch (err) {
+            console.error("❌ Could not load weights.", err);
+            document.getElementById("weightsStatus").textContent = "Could not load weights.";
+            return;
+        }
+
+        this.renderBoardSet(data.mg, "weightsGridMg");
+        this.renderBoardSet(data.eg, "weightsGridEg");
+        this.renderFeatures(data.features);
+
+        const trained = [...data.mg, ...data.eg].some(b => b.squares.some(v => v !== 0))
+            || data.features.some(f => f.value !== 0);
+
+        document.getElementById("weightsStatus").textContent = trained
+            ? "Where the learned engine thinks each piece belongs. Blue = preferred, red = avoided. Midgame vs endgame tables are blended by how much material is left."
+            : "No training yet — everything is neutral. Run some learned games on the Watch page.";
+    },
+
+    // pieces: [{ name, squares[64] }]. Prepends an "Overall" board summing the set.
+    renderBoardSet(pieces, containerId) {
+        const overall = new Array(64).fill(0);
+        for (const piece of pieces)
+            for (let sq = 0; sq < 64; sq++)
+                overall[sq] += piece.squares[sq];
+
+        const boards = [{ name: "Overall", squares: overall }, ...pieces];
+        const grid = document.getElementById(containerId);
+        grid.innerHTML = "";
+        boards.forEach(board => grid.appendChild(this.buildBoard(board)));
+    },
+
+    buildBoard(board) {
+        const wrapper = document.createElement("div");
+        wrapper.className = "weightBoard";
+
+        const maxAbs = board.squares.reduce((m, v) => Math.max(m, Math.abs(v)), 0);
+
+        const header = document.createElement("div");
+        header.className = "weightBoardHeader";
+        if (board.name !== "Overall") {
+            const icon = document.createElement("img");
+            icon.src = `/images/Chess Images/White${board.name}.svg`;
+            icon.alt = board.name;
+            icon.className = "weightBoardIcon";
+            header.appendChild(icon);
+        }
+        const title = document.createElement("span");
+        title.textContent = board.name;
+        header.appendChild(title);
+        const range = document.createElement("span");
+        range.className = "weightRange";
+        range.textContent = maxAbs === 0 ? "neutral" : `±${maxAbs}`;
+        header.appendChild(range);
+        wrapper.appendChild(header);
+
+        const heat = document.createElement("div");
+        heat.className = "miniHeat";
+
+        for (let row = 0; row < 8; row++) {
+            const rankLabel = document.createElement("div");
+            rankLabel.className = "heatLabel";
+            rankLabel.textContent = 8 - row;          // rank 8 at top, 1 at bottom
+            heat.appendChild(rankLabel);
+
+            for (let col = 0; col < 8; col++) {
+                const rank = 7 - row;                 // rank index, 0 = rank 1
+                const sq = rank * 8 + col;            // white-relative square (A1 = 0)
+                heat.appendChild(this.buildSquare(board.squares[sq], sq, maxAbs));
+            }
+        }
+
+        heat.appendChild(this.cornerSpacer());
+        for (let col = 0; col < 8; col++) {
+            const fileLabel = document.createElement("div");
+            fileLabel.className = "heatLabel";
+            fileLabel.textContent = String.fromCharCode(97 + col);
+            heat.appendChild(fileLabel);
+        }
+
+        wrapper.appendChild(heat);
+        return wrapper;
+    },
+
+    buildSquare(value, sq, maxAbs) {
+        const cell = document.createElement("div");
+        cell.className = "heatSquare";
+
+        if (value !== 0 && maxAbs > 0) {
+            const ratio = Math.abs(value) / maxAbs;
+            const alpha = (0.12 + 0.88 * ratio).toFixed(3);
+            cell.style.backgroundColor = value > 0
+                ? `rgba(74, 134, 232, ${alpha})`      // high -> blue
+                : `rgba(232, 74, 74, ${alpha})`;      // low  -> red
+            cell.textContent = value;
+        }
+
+        const file = String.fromCharCode(97 + (sq & 7));
+        const rank = (sq >> 3) + 1;
+        cell.title = `${file}${rank}: ${value}`;
+        return cell;
+    },
+
+    cornerSpacer() {
+        const spacer = document.createElement("div");
+        spacer.className = "heatLabel";
+        return spacer;
+    },
+
+    // features: [{ name, value }]
+    renderFeatures(features) {
+        const panel = document.getElementById("featureWeights");
+        panel.innerHTML = "";
+
+        const maxAbs = features.reduce((m, f) => Math.max(m, Math.abs(f.value)), 0);
+
+        features.forEach(feature => {
+            const row = document.createElement("div");
+            row.className = "featureRow";
+
+            const label = document.createElement("span");
+            label.className = "featureLabel";
+            label.textContent = feature.name;
+
+            const track = document.createElement("div");
+            track.className = "featureTrack";
+            const bar = document.createElement("div");
+            bar.className = "featureBar";
+            const ratio = maxAbs === 0 ? 0 : Math.abs(feature.value) / maxAbs;
+            bar.style.width = `${(ratio * 100).toFixed(1)}%`;
+            bar.style.backgroundColor = feature.value >= 0
+                ? "rgba(74, 134, 232, 0.85)"
+                : "rgba(232, 74, 74, 0.85)";
+            track.appendChild(bar);
+
+            const value = document.createElement("span");
+            value.className = "featureValue";
+            value.textContent = feature.value;
+
+            row.append(label, track, value);
+            panel.appendChild(row);
+        });
+    }
+};
+
+window.addEventListener("load", () => Weights.init());
+
+console.log("Weights.js loaded");

JoshHeaps.Net/wwwroot/js/ChessScripts/chessMain.js

@@ -30,6 +30,18 @@ function resetCopyPgn() {
 window.copyPgn = copyPgn;
 window.showCopyPgn = showCopyPgn;
 
+// Mobile slide-up menu (move list + secondary actions).
+function toggleMenu() {
+    document.body.classList.toggle("menu-open");
+}
+
+function closeMenu() {
+    document.body.classList.remove("menu-open");
+}
+
+window.toggleMenu = toggleMenu;
+window.closeMenu = closeMenu;
+
 async function forfeitCurrentGame() {
     const gameId = ChessUtils.getCookie("chessGameId");
     const playerId = ChessUtils.getCookie("chessPlayerId");
@@ -44,6 +56,7 @@ async function forfeitCurrentGame() {
 }
 
 async function startNewGame() {
+    closeMenu();
     await ChessSignalR.stopConnection();
     await forfeitCurrentGame();
     resetCopyPgn();
@@ -63,7 +76,7 @@ async function startNewGame() {
         await ChessSignalR.setupConnection();
 
         const gameState = await ChessAPI.getGameState(gameData.gameId);
-        ChessBoard.renderPieces(gameState.pieces);
+        ChessBoard.renderState(gameState);
 
     } catch (error) {
         console.error("Failed to start new game:", error);
@@ -71,13 +84,15 @@ async function startNewGame() {
 }
 
 async function startCPUGame() {
+    closeMenu();
     await ChessSignalR.stopConnection();
     await forfeitCurrentGame();
     resetCopyPgn();
 
     try {
         const difficulty = await ChessModals.promptDifficulty();
-        const gameData = await ChessAPI.createCPUGame(difficulty);
+        const color = await ChessModals.promptColor();
+        const gameData = await ChessAPI.createCPUGame(difficulty, color);
 
         GameState.setGameInfo(gameData.gameId, gameData.id, gameData.isWhite);
         GameState.clearPreviousMove();
@@ -91,7 +106,7 @@ async function startCPUGame() {
         await ChessSignalR.setupConnection();
 
         const gameState = await ChessAPI.getGameState(gameData.gameId);
-        ChessBoard.renderPieces(gameState.pieces);
+        ChessBoard.renderState(gameState);
 
     } catch (error) {
         console.error("Failed to start CPU game:", error);
@@ -111,7 +126,7 @@ async function resumeSavedGame() {
             GameState.setGameInfo(savedGameId, savedPlayerId, savedPlayerIsWhite === "true");
 
             await ChessSignalR.setupConnection();
-            ChessBoard.renderPieces(gameState.pieces);
+            ChessBoard.renderState(gameState);
 
         } catch (err) {
             console.warn("Saved game not found or expired.", err);

JoshHeaps.Net/wwwroot/js/casino/holdem/actionBar.js

@@ -0,0 +1,625 @@
+// The bar a dealer's thumb lives on while a hand is running: who's to act, what it
+// costs them, and one tap per decision. Sits at the bottom of the screen on a phone
+// so it's reachable without looking, and re-renders after every action because the
+// next player's numbers are different.
+const ActionBar = {
+    state: null,
+    hooks: null,
+    raiseOpen: false,
+    raiseDraft: null,
+
+    mount(state, hooks) {
+        this.state = state;
+        this.hooks = hooks;
+        this.watchHeight();
+        this.render();
+    },
+
+    // The bar is fixed to the bottom of the screen, so everything else has to know how
+    // tall it is or the table simply runs underneath it — on a 640px-tall phone the
+    // bottom seats of the oval were sitting behind the Fold button. Its height isn't a
+    // constant either: opening the raise pad grows it. Publishing the measured height
+    // as a custom property lets the layout and the toast both stay clear of it without
+    // anyone guessing a number.
+    watchHeight() {
+        const host = document.getElementById("actionBar");
+        if (!host || this.heightWatcher) return;
+
+        const publish = () => {
+            const visible = !host.hidden;
+            const height = visible ? host.getBoundingClientRect().height : 0;
+            document.documentElement.style.setProperty("--actionBarHeight", `${Math.round(height)}px`);
+            this.publishFeltRoom(height);
+        };
+
+        if (typeof ResizeObserver === "function") {
+            this.heightWatcher = new ResizeObserver(publish);
+            this.heightWatcher.observe(host);
+        }
+        window.addEventListener("resize", publish);
+        window.addEventListener("orientationchange", publish);
+        publish();
+    },
+
+    // Half a seat, the gap left under the lowest one, and the smallest felt worth
+    // drawing. A seat is about 73px tall at every width — the puck is text-sized, not
+    // table-sized — so the overhang is a constant rather than something read back off
+    // the layout this is about to change. Measuring it would mean shrinking the felt,
+    // moving the seats, and getting a different answer on the next pass.
+    SEAT_OVERHANG_PX: 37,
+    FELT_GAP_PX: 8,
+    FELT_MIN_PX: 220,
+
+    // How tall the felt can be and still leave the whole ring of seats above the bar.
+    //
+    // Publishing the bar's height was only half the job. The wide layout never used it:
+    // the felt sizes itself from its own width — a box 72% as tall as it is wide — and
+    // so has no idea what is underneath it. The bar meanwhile grows with the hand, from
+    // 117px to 172px the moment there's a side pot to show, which is exactly when the
+    // dealer most needs to see who is still in. Measured with two side pots, the bottom
+    // seat sat 22px into the bar at 1280x900, 54px at 1600x1000, 23px at 768x1024.
+    //
+    // The wrap's offset is taken in document space rather than viewport space, so
+    // scrolling the page doesn't resize the table under the dealer's hands.
+    publishFeltRoom(barHeight) {
+        const wrap = document.getElementById("pokerTableWrap");
+        if (!wrap) return;
+        const topInDocument = wrap.getBoundingClientRect().top + window.scrollY;
+        const room = window.innerHeight - barHeight - topInDocument -
+            this.SEAT_OVERHANG_PX - this.FELT_GAP_PX;
+        document.documentElement.style.setProperty(
+            "--feltRoomPx", `${Math.max(this.FELT_MIN_PX, Math.round(room))}px`);
+    },
+
+    // Anything to act on? A hand with nobody dealt in doesn't get a bar — and that
+    // still holds during setup, because a seated player is a live seat whether or not
+    // the betting has been opened. An empty table stays uncluttered.
+    isRunning() {
+        return Betting.liveSeats(this.state).length > 0;
+    },
+
+    render() {
+        const host = document.getElementById("actionBar");
+        if (!host) return;
+        host.innerHTML = "";
+
+        if (!this.isRunning()) {
+            host.hidden = true;
+            document.body.classList.remove("hasActionBar");
+            document.documentElement.style.setProperty("--actionBarHeight", "0px");
+            this.stopTankTimer();
+            this.tankSeatIndex = null;
+            return;
+        }
+        host.hidden = false;
+        document.body.classList.add("hasActionBar");
+
+        host.appendChild(this.renderStatus());
+
+        const breakdown = this.renderPotBreakdown();
+        if (breakdown) host.appendChild(breakdown);
+
+        if (!this.state.bettingOpen) {
+            host.appendChild(this.renderDealPrompt());
+        } else if (Betting.isHandOver(this.state)) {
+            host.appendChild(this.renderHandOver());
+        } else if (this.state.actingSeatIndex === null || this.state.actingSeatIndex === undefined) {
+            host.appendChild(this.renderStreetDone());
+        } else if (this.raiseOpen) {
+            host.appendChild(this.renderRaisePad());
+        } else {
+            host.appendChild(this.renderActions());
+        }
+
+        this.syncTankTimer();
+    },
+
+    renderStatus() {
+        const row = document.createElement("div");
+        row.className = "actionStatus";
+
+        const street = document.createElement("span");
+        street.className = "actionStreet";
+        street.textContent = Betting.streetLabel(this.state.street);
+        row.appendChild(street);
+
+        const pot = document.createElement("span");
+        pot.className = "actionPot";
+        pot.textContent = `Pot ${Money.format(Betting.potSoFar(this.state))}`;
+        row.appendChild(pot);
+
+        // How many are still in the hand — part of the standard per-street
+        // announcement, and the number a dealer is asked for most often. Before the
+        // deal it counts the table as it will be dealt, so a busted player waiting on a
+        // rebuy isn't announced as one of the players. Read-only: the sitting-out
+        // itself happens when the hand is dealt, not while the bar is being drawn.
+        const counted = this.state.bettingOpen ? this.state : Betting.tableAsDealt(this.state);
+        const remaining = Betting.liveSeats(counted).length;
+        const players = document.createElement("span");
+        players.className = "actionPlayers";
+        players.textContent = `${remaining} ${remaining === 1 ? "player" : "players"}`;
+        row.appendChild(players);
+
+        // Nobody is being asked to act because nobody can — say so, or the bar just
+        // looks like it's waiting for something.
+        if (Betting.isRunningOut(this.state) && !Betting.isHandOver(this.state)) {
+            const runout = document.createElement("span");
+            runout.className = "actionRunout";
+            const stillIn = Betting.liveSeats(this.state).length;
+            runout.textContent = `All-in — running out the board (${stillIn} players)`;
+            row.appendChild(runout);
+        }
+
+        const index = this.state.actingSeatIndex;
+        if (index !== null && index !== undefined && !Betting.isHandOver(this.state)) {
+            const player = this.state.seats[index];
+            const who = document.createElement("span");
+            who.className = "actionWho";
+            who.textContent = `${HoldemState.displayName(player, index)} · ${Money.format(Betting.stackOf(this.state, player))} behind`;
+            row.appendChild(who);
+
+            const tank = document.createElement("span");
+            tank.className = "actionTank";
+            tank.id = "actionTank";
+            tank.title = "How long this player has been thinking";
+            tank.textContent = "0:00";
+            row.appendChild(tank);
+        }
+
+        // A standing control rather than a toast per action: a dealer taps this bar
+        // constantly, and a toast after every fold would be noise they'd learn to
+        // ignore — which is exactly when they'd miss the one that mattered.
+        const undoLabel = this.hooks.lastActionLabel();
+        if (undoLabel) {
+            const undo = document.createElement("button");
+            undo.type = "button";
+            undo.className = "actionUndo";
+            undo.title = `Undo ${undoLabel}`;
+            undo.textContent = `↶ ${undoLabel}`;
+            undo.addEventListener("click", () => this.hooks.undoLast());
+            row.appendChild(undo);
+        }
+
+        return row;
+    },
+
+    // ---- Think timer ----
+    //
+    // A player who hasn't noticed the action is on them costs more time than anything
+    // else a dealer does, so the bar shows how long the current player has been in the
+    // tank. It's a stopwatch, not a shot clock: nothing happens when it grows, it just
+    // tells the dealer when it's worth a nudge.
+    NUDGE_AFTER_S: 30,
+    SLOW_AFTER_S: 60,
+
+    tankSeatIndex: null,
+    tankStartedAt: null,
+    tankInterval: null,
+
+    // Restarts only when the action actually moves — a re-render for any other reason
+    // (a chip edit, a name change) must not put a thinking player back to zero.
+    syncTankTimer() {
+        const index = this.state.actingSeatIndex;
+        const running = index !== null && index !== undefined && !Betting.isHandOver(this.state);
+
+        if (!running) {
+            this.stopTankTimer();
+            this.tankSeatIndex = null;
+            return;
+        }
+
+        if (this.tankSeatIndex !== index) {
+            this.tankSeatIndex = index;
+            this.tankStartedAt = Date.now();
+        }
+
+        if (!this.tankInterval) {
+            this.tankInterval = setInterval(() => this.paintTank(), 1000);
+        }
+        this.paintTank();
+    },
+
+    stopTankTimer() {
+        if (this.tankInterval) {
+            clearInterval(this.tankInterval);
+            this.tankInterval = null;
+        }
+    },
+
+    // Updates only the timer's own text, so the seconds ticking over never rebuilds the
+    // buttons under the dealer's thumb.
+    paintTank() {
+        const el = document.getElementById("actionTank");
+        if (!el || this.tankStartedAt === null) return;
+
+        const seconds = Math.floor((Date.now() - this.tankStartedAt) / 1000);
+        const mins = Math.floor(seconds / 60);
+        el.textContent = `${mins}:${String(seconds % 60).padStart(2, "0")}`;
+        el.classList.toggle("tankNudge", seconds >= this.NUDGE_AFTER_S && seconds < this.SLOW_AFTER_S);
+        el.classList.toggle("tankSlow", seconds >= this.SLOW_AFTER_S);
+    },
+
+    // Shown only once someone is all-in and the money has actually split — a single
+    // undivided pot needs no announcement, and a line that's always there stops being
+    // read.
+    renderPotBreakdown() {
+        // Only worth showing once someone is actually all-in. Mid-street the amounts in
+        // front of players are unequal all the time — the blinds alone are unequal —
+        // and layering that would announce a side pot on every hand before anyone had
+        // even acted.
+        const someoneAllIn = this.state.seats.some(
+            player => player.inHand && Betting.handTotal(player) > 0 && Betting.stackOf(this.state, player) <= 0
+        );
+        if (!someoneAllIn) return null;
+
+        const contributions = this.state.seats.map((player, index) => ({
+            id: player.id,
+            index,
+            contribution: Betting.handTotal(player),
+            folded: player.folded,
+        }));
+
+        const nameById = new Map(
+            this.state.seats.map((player, index) => [player.id, HoldemState.displayName(player, index)])
+        );
+
+        return Render.buildPotBreakdown(
+            PotCalculator.layers(contributions),
+            PotCalculator.uncalledReturns(contributions),
+            id => nameById.get(id)
+        );
+    },
+
+    // Which key presses each button. Shown on the button itself and hidden on touch
+    // devices — a shortcut nobody can discover may as well not exist, and a key badge
+    // on a phone is just clutter.
+    KEY_HINTS: {
+        actionFold: "F",
+        actionCheck: "C",
+        actionCall: "C",
+        actionRaise: "R",
+        actionAdvance: "↵",
+        raiseConfirm: "↵",
+        raiseCancel: "esc",
+    },
+
+    button(label, className, onClick, sublabel) {
+        const btn = document.createElement("button");
+        btn.type = "button";
+        btn.className = `actionBtn ${className}`;
+
+        const main = document.createElement("span");
+        main.className = "actionBtnLabel";
+        main.textContent = label;
+        btn.appendChild(main);
+
+        const hint = this.KEY_HINTS[className];
+        if (hint) {
+            const kbd = document.createElement("kbd");
+            kbd.className = "actionKey";
+            kbd.textContent = hint;
+            btn.appendChild(kbd);
+        }
+
+        if (sublabel) {
+            const sub = document.createElement("span");
+            sub.className = "actionBtnSub";
+            sub.textContent = sublabel;
+            btn.appendChild(sub);
+        }
+
+        btn.addEventListener("click", onClick);
+        return btn;
+    },
+
+    // Every action taken from the bar goes through here, which is also where it gets
+    // recorded so it can be taken back. A misclick on Fold is the one mistake in this
+    // tool a dealer can't talk their way out of.
+    commit(label, mutate) {
+        this.hooks.beginAction(label);
+        mutate();
+        this.hooks.save(this.state);
+        this.hooks.rerender();
+    },
+
+    renderActions() {
+        const index = this.state.actingSeatIndex;
+        const player = this.state.seats[index];
+        const owed = Betting.toCall(this.state, player);
+        const stack = Betting.stackOf(this.state, player);
+        const who = HoldemState.displayName(player, index);
+
+        const row = document.createElement("div");
+        row.className = "actionButtons";
+
+        row.appendChild(this.button("Fold", "actionFold", () => this.commit(`${who}'s fold`, () => Betting.fold(this.state, index))));
+
+        if (owed <= 0) {
+            row.appendChild(this.button("Check", "actionCheck", () => this.commit(`${who}'s check`, () => Betting.check(this.state, index))));
+        } else if (owed >= stack) {
+            // Calling would put them all-in, so say that rather than quoting a number
+            // they can't cover.
+            row.appendChild(this.button("Call all-in", "actionCall", () => this.commit(`${who}'s all-in`, () => Betting.allIn(this.state, index)), Money.format(stack)));
+        } else {
+            row.appendChild(this.button("Call", "actionCall", () => this.commit(`${who}'s call`, () => Betting.call(this.state, index)), Money.format(owed)));
+        }
+
+        if (stack > owed) {
+            // Not "does this player owe anything" — the big blind owes nothing and is
+            // still raising. It's whether there is a live bet to raise.
+            const raising = Betting.wagerVerb(this.state) === "raise";
+            row.appendChild(this.button(raising ? "Raise" : "Bet", "actionRaise", () => {
+                this.raiseOpen = true;
+                this.raiseDraft = Math.min(Betting.minRaiseTo(this.state), Betting.committed(player) + stack);
+                this.render();
+            }));
+        }
+
+        return row;
+    },
+
+    // Quick amounts first, keypad second — a dealer calling "raise to sixty" wants a
+    // button, and only reaches for digits when the table does something odd.
+    renderRaisePad() {
+        // A toast is transient news about the action just taken; the raise pad is the
+        // dealer deciding the next one. On a short screen they compete for the same
+        // strip: the pad makes the bar 217px tall on a 640px phone, and the toast —
+        // which floats just above the bar — gets pushed up over the table, covering
+        // seats outright. Rather than squeeze both in, the older one gets out of the
+        // way. Nothing is lost: the toast's Undo is also the bar's own undo control.
+        if (typeof Toast !== "undefined" && Toast.dismiss) Toast.dismiss();
+
+        const index = this.state.actingSeatIndex;
+        const player = this.state.seats[index];
+        const stack = Betting.stackOf(this.state, player);
+        const maxTo = Betting.round(Betting.committed(player) + stack);
+        const pot = Betting.potSoFar(this.state);
+        // Two different minimums, and conflating them was a bug. `minTo` is clamped to
+        // what this player can actually put in, which is what the Min button should
+        // offer. `legalMin` is what the rules require — for a short stack the two are
+        // different, and it's the rules one the warnings have to be measured against,
+        // or a player whose whole stack is under a full raise never gets told that.
+        const legalMin = Betting.minRaiseTo(this.state);
+        const minTo = Math.min(legalMin, maxTo);
+        const raising = Betting.wagerVerb(this.state) === "raise";
+
+        const wrap = document.createElement("div");
+        wrap.className = "raisePad";
+
+        const quick = document.createElement("div");
+        quick.className = "raiseQuick";
+
+        const options = [
+            { label: "Min", value: minTo },
+            { label: "½ pot", value: Betting.round(this.state.currentBet + pot / 2) },
+            { label: "Pot", value: Betting.round(this.state.currentBet + pot) },
+            { label: "All-in", value: maxTo },
+        ];
+        options.forEach(option => {
+            const value = Math.max(minTo, Math.min(option.value, maxTo));
+            const btn = this.button(option.label, "raiseQuickBtn", () => {
+                this.raiseDraft = value;
+                this.render();
+            }, Money.format(value));
+            if (Betting.round(this.raiseDraft) === value) btn.classList.add("selected");
+            quick.appendChild(btn);
+        });
+        wrap.appendChild(quick);
+
+        const entry = document.createElement("div");
+        entry.className = "raiseEntry";
+
+        const input = document.createElement("input");
+        input.type = "text";
+        input.inputMode = "decimal";
+        input.className = "raiseInput";
+        input.value = this.raiseDraft ?? minTo;
+        input.setAttribute("aria-label", raising ? "Raise to amount" : "Bet amount");
+        input.addEventListener("input", () => {
+            this.raiseDraft = input.value.replace(/[^0-9.]/g, "");
+            this.updateRaiseNote(wrap, legalMin, maxTo);
+        });
+        entry.appendChild(input);
+
+        entry.appendChild(this.button("Cancel", "raiseCancel", () => {
+            this.raiseOpen = false;
+            this.render();
+        }));
+
+        // "Raise to $60" and "Bet $10" — a bet isn't *to* anything, there's nothing
+        // under it to raise past.
+        entry.appendChild(this.button(raising ? "Raise to" : "Bet", "raiseConfirm", () => {
+            const target = Math.max(0, Math.min(Number(this.raiseDraft) || 0, maxTo));
+            this.raiseOpen = false;
+            const who = HoldemState.displayName(player, index);
+            const label = raising
+                ? `${who}'s raise to ${Money.format(target)}`
+                : `${who}'s bet of ${Money.format(target)}`;
+            this.commit(label, () => Betting.raiseTo(this.state, index, target));
+        }));
+
+        wrap.appendChild(entry);
+
+        const note = document.createElement("p");
+        note.className = "raiseNote";
+        note.hidden = true;
+        wrap.appendChild(note);
+        this.updateRaiseNote(wrap, legalMin, maxTo);
+
+        return wrap;
+    },
+
+    // Says something when the amount typed isn't a legal raise. It never blocks —
+    // a dealer overruling the arithmetic is right more often than the arithmetic is,
+    // and the whole tool is built on tapping what the humans actually did.
+    //
+    // But an under-minimum raise from a player with chips behind them is the single
+    // most common thing that stops a home game dead, and until now the bar took it
+    // without a word: type 13 when the minimum is 18 and it was simply accepted. The
+    // engine then treats it as a short raise and correctly doesn't reopen the betting,
+    // which is right for an all-in and wrong for somebody who just misheard the bet.
+    updateRaiseNote(wrap, minTo, maxTo) {
+        const note = wrap.querySelector(".raiseNote");
+        if (!note) return;
+
+        const typed = Number(this.raiseDraft);
+        const current = this.state.currentBet || 0;
+        const raising = Betting.wagerVerb(this.state) === "raise";
+
+        if (!Number.isFinite(typed) || typed <= 0) { note.hidden = true; return; }
+
+        // Going all-in for less than a full raise is perfectly legal, and worth saying
+        // out loud because of what follows from it.
+        const isAllIn = Math.abs(typed - maxTo) < Betting.EPSILON_CHIPS;
+
+        if (typed > current && typed < minTo - Betting.EPSILON_CHIPS && !isAllIn) {
+            // The way out of an under-minimum differs: with a bet in front of you the
+            // alternative is calling it, and with an empty pot there's nothing to call.
+            note.textContent = raising
+                ? `${Money.format(typed)} is under the ${Money.format(minTo)} minimum. A legal raise is ${Money.format(minTo)} or more — otherwise it's a call, or all-in.`
+                : `${Money.format(typed)} is under the ${Money.format(minTo)} minimum. A legal bet is ${Money.format(minTo)} or more — otherwise it's a check, or all-in.`;
+            note.className = "raiseNote raiseNoteWarn";
+            note.hidden = false;
+            return;
+        }
+
+        if (isAllIn && typed > current && typed < minTo - Betting.EPSILON_CHIPS) {
+            note.textContent = raising
+                ? `All-in for less than a full raise. Legal, but it doesn't reopen the betting — anyone who has already acted owes the difference or folds.`
+                : `All-in for less than a full bet. Legal, but it doesn't reopen the betting — anyone who has already checked can call it or fold, not raise.`;
+            note.className = "raiseNote raiseNoteInfo";
+            note.hidden = false;
+            return;
+        }
+
+        if (typed > current && typed < current + Betting.EPSILON_CHIPS) { note.hidden = true; return; }
+
+        if (typed > maxTo + Betting.EPSILON_CHIPS) {
+            note.textContent = `More than they have. This goes in as all-in for ${Money.format(maxTo)}.`;
+            note.className = "raiseNote raiseNoteInfo";
+            note.hidden = false;
+            return;
+        }
+
+        if (typed <= current) {
+            note.textContent = `${Money.format(typed)} is not above the ${Money.format(current)} already bet — that's a call, not a raise.`;
+            note.className = "raiseNote raiseNoteWarn";
+            note.hidden = false;
+            return;
+        }
+
+        note.hidden = true;
+    },
+
+    // The table is set but the cards aren't out. This is the step that used to happen
+    // by itself the instant the previous hand ended, which meant blinds were committed
+    // while people were still sitting down — and the blind badges would drift away from
+    // the money already posted as seats changed. Now the dealer says when.
+    renderDealPrompt() {
+        const wrap = document.createElement("div");
+        wrap.className = "dealPrompt";
+
+        const preview = Betting.blindPreview(this.state);
+        const seated = Betting.liveSeats(this.state).length;
+        const broke = Betting.brokeSeats(this.state);
+        const name = i => HoldemState.displayName(this.state.seats[i], i);
+        const listNames = indexes => indexes.length === 1
+            ? name(indexes[0])
+            : `${indexes.slice(0, -1).map(name).join(", ")} and ${name(indexes[indexes.length - 1])}`;
+
+        const line = document.createElement("p");
+        line.className = "dealPromptLine";
+
+        if (!preview) {
+            // Two players is the least you can deal. Say what's missing rather than
+            // offering a button that would quietly do nothing — and say the *right*
+            // thing: "only one player is dealt in" is wrong when four are sitting there
+            // and three of them are just out of chips.
+            const withChips = seated - broke.length;
+            if (broke.length > 0 && withChips < 2) {
+                line.textContent = withChips === 1
+                    ? `Only ${listNames(Betting.liveSeats(this.state).map(s => s.index).filter(i => !broke.includes(i)))} has chips — ${listNames(broke)} ${broke.length === 1 ? "needs" : "need"} to buy in.`
+                    : "Nobody at the table has chips left. Add a buy-in to deal.";
+            } else {
+                line.textContent = seated === 0
+                    ? "Nobody is dealt in yet. Tap a seat to add a player."
+                    : "Only one player is dealt in — a hand needs two.";
+            }
+            line.classList.add("dealPromptBlocked");
+            wrap.appendChild(line);
+            return wrap;
+        }
+
+        line.textContent =
+            `${name(preview.sbIndex)} posts ${Money.format(preview.smallBlind)}, ` +
+            `${name(preview.bbIndex)} posts ${Money.format(preview.bigBlind)}` +
+            `${preview.headsUp ? " · heads-up" : ""}${preview.manual ? " · blinds set by hand" : ""}`;
+        wrap.appendChild(line);
+
+        // Dealing relocates a button sitting on an empty chair. That has to be said
+        // before it happens rather than discovered afterwards — a fresh table starts
+        // the button on seat 1 whether or not anyone is sitting there.
+        if (preview.buttonMoves) {
+            const moved = document.createElement("p");
+            moved.className = "dealPromptLine dealPromptAside";
+            moved.textContent =
+                `Button moves to ${name(preview.buttonIndex)} — seat ${this.state.dealerSeatIndex + 1} is empty.`;
+            wrap.appendChild(moved);
+        }
+
+        // Dealing sits out anyone with nothing behind. Said before it happens, for the
+        // same reason the button move is: a dealer shouldn't find out from the felt.
+        if (preview.satOut.length > 0) {
+            const out = document.createElement("p");
+            out.className = "dealPromptLine dealPromptAside";
+            out.textContent = `${listNames(preview.satOut)} ${preview.satOut.length === 1 ? "has" : "have"} no chips — ` +
+                `${preview.satOut.length === 1 ? "sitting" : "they sit"} out this hand.`;
+            wrap.appendChild(out);
+        }
+
+        const row = document.createElement("div");
+        row.className = "actionButtons";
+        row.appendChild(this.button("Post blinds & deal", "actionDeal", () => {
+            this.commit("dealing the hand", () => Betting.beginHand(this.state));
+        }));
+        wrap.appendChild(row);
+
+        return wrap;
+    },
+
+    renderStreetDone() {
+        const row = document.createElement("div");
+        row.className = "actionButtons";
+
+        const isRiver = this.state.street === "river";
+        const label = isRiver ? "Showdown — resolve pot" : `Deal ${Betting.streetLabel(Betting.STREETS[Betting.STREETS.indexOf(this.state.street) + 1])}`;
+
+        row.appendChild(this.button(label, "actionAdvance", () => {
+            if (isRiver) {
+                this.hooks.resolvePot();
+                return;
+            }
+            this.commit(`dealing the ${Betting.streetLabel(Betting.STREETS[Betting.STREETS.indexOf(this.state.street) + 1]).toLowerCase()}`, () => Betting.closeStreet(this.state));
+        }));
+
+        return row;
+    },
+
+    renderHandOver() {
+        const row = document.createElement("div");
+        row.className = "actionButtons";
+        const live = Betting.liveSeats(this.state);
+        const winner = live.length === 1 ? HoldemState.displayName(live[0].player, live[0].index) : null;
+
+        row.appendChild(this.button(
+            winner ? `Award pot to ${winner}` : "Resolve pot",
+            "actionAdvance",
+            () => this.hooks.resolvePot()
+        ));
+        return row;
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = ActionBar;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/addChips.js

@@ -0,0 +1,92 @@
+// "Add chips" — a rebuy, a top-up, or the first buy-in of the night.
+//
+// Quick amounts come off the table's starting stack, because a rebuy is almost
+// always one buy-in, sometimes half or two. The keypad is there for the times it
+// isn't. Recorded as cash in as well as chips, so at the end of the night the
+// dealer can say what each player actually handed over.
+const AddChips = {
+    state: null,
+    onConfirm: null,
+    seatIndex: null,
+    draft: "",
+
+    open(state, seatIndex, onConfirm) {
+        this.state = state;
+        this.seatIndex = seatIndex;
+        this.onConfirm = onConfirm;
+        this.draft = String(this.baseAmount());
+        this.render();
+        document.getElementById("addChipsOverlay").hidden = false;
+    },
+
+    close() {
+        document.getElementById("addChipsOverlay").hidden = true;
+    },
+
+    // The table's starting stack if there is one, otherwise something sane to nudge
+    // rather than an empty box.
+    baseAmount() {
+        const configured = Number(this.state.defaultStack);
+        if (!Number.isNaN(configured) && configured > 0) return configured;
+        const bb = Number(this.state.bigBlind) || 0;
+        return bb > 0 ? bb * 100 : 100;
+    },
+
+    quickAmounts() {
+        const base = this.baseAmount();
+        return [
+            { label: "½ buy-in", value: Money.round(base / 2) },
+            { label: "Buy-in", value: base },
+            { label: "2 buy-ins", value: base * 2 },
+        ];
+    },
+
+    render() {
+        const player = this.state.seats[this.seatIndex];
+        document.getElementById("addChipsTitle").textContent =
+            `Add chips — ${HoldemState.displayName(player, this.seatIndex)}`;
+
+        const stack = Betting.stackOf(this.state, player);
+        const boughtIn = Number(player.buyIns) || 0;
+        document.getElementById("addChipsSubtitle").textContent = boughtIn > 0
+            ? `${Money.format(stack)} in front · ${Money.format(boughtIn)} in so far`
+            : `${Money.format(stack)} in front`;
+
+        const quick = document.getElementById("addChipsQuick");
+        quick.innerHTML = "";
+        this.quickAmounts().forEach(option => {
+            const btn = document.createElement("button");
+            btn.type = "button";
+            btn.className = "addChipsQuickBtn";
+            btn.classList.toggle("selected", Number(this.draft) === option.value);
+
+            const label = document.createElement("span");
+            label.className = "addChipsQuickLabel";
+            label.textContent = option.label;
+            const amount = document.createElement("span");
+            amount.className = "addChipsQuickAmount";
+            amount.textContent = Money.format(option.value);
+
+            btn.appendChild(label);
+            btn.appendChild(amount);
+            btn.addEventListener("click", () => {
+                this.draft = String(option.value);
+                this.render();
+            });
+            quick.appendChild(btn);
+        });
+
+        const input = document.getElementById("addChipsInput");
+        input.value = this.draft;
+    },
+
+    confirm() {
+        const amount = Math.max(0, Number(document.getElementById("addChipsInput").value) || 0);
+        this.close();
+        if (amount > 0) this.onConfirm(this.seatIndex, Money.round(amount));
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = AddChips;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/betting.js

@@ -0,0 +1,483 @@
+// Live betting: who's to act, what it costs them, and where the money goes.
+//
+// This is bookkeeping, not a game — the dealer taps what the humans at the table
+// actually did, and the tool keeps the arithmetic straight. It deliberately never
+// blocks an action it thinks is "illegal"; a dealer overruling the maths is right
+// more often than the maths is.
+//
+// Money model: `player.committed` is what a seat has put in on the current street.
+// When a street closes it sweeps into `player.amountOverride`, which is the seat's
+// total for the hand — the same field the pot badge, the pot wizard, the standings
+// and the CSV already read. So the betting bar is a fast way to fill in a field
+// that already existed, and nothing downstream had to change.
+const Betting = {
+    STREETS: ["preflop", "flop", "turn", "river"],
+
+    streetLabel(street) {
+        return { preflop: "Pre-flop", flop: "Flop", turn: "Turn", river: "River" }[street] || "Pre-flop";
+    },
+
+    round(amount) {
+        return Money.round(amount);
+    },
+
+    // ---- Reading the table ----
+
+    liveSeats(state) {
+        return state.seats
+            .map((player, index) => ({ player, index }))
+            .filter(s => s.player.inHand && !s.player.folded);
+    },
+
+    // Who would post if the hand were dealt right now. Used to preview the blinds
+    // while the table is still being set, so a dealer can see where they'll land
+    // before any money moves.
+    // A seat that is dealt in, has nothing in the pot, and has no chips behind.
+    //
+    // Not the same as all-in: an all-in player has money riding on the hand. This is
+    // somebody who busted and hasn't bought back in yet, which a home game produces
+    // about once an hour. A seat with no stack *recorded* isn't broke either —
+    // stackOf falls back to the table's starting stack for those — only an explicit
+    // zero counts.
+    brokeSeats(state) {
+        const broke = [];
+        state.seats.forEach((player, index) => {
+            if (!player.inHand) return;
+            if (this.handTotal(player) > this.EPSILON_CHIPS) return;
+            if (this.stackOf(state, player) > this.EPSILON_CHIPS) return;
+            broke.push(index);
+        });
+        return broke;
+    },
+
+    // The table as it will be once the seats that can't post are dealt around. A view,
+    // not a change: the preview has to ask the same question the deal will answer, and
+    // asking it of a different shape of table is how the two came apart last time.
+    tableAsDealt(state) {
+        const broke = this.brokeSeats(state);
+        if (broke.length === 0) return state;
+        const skip = new Set(broke);
+        return {
+            ...state,
+            seats: state.seats.map((player, index) =>
+                skip.has(index) ? { ...player, inHand: false, folded: false } : player),
+        };
+    },
+
+    blindPreview(state) {
+        // Dealing relocates a button parked on an empty chair before it works out who
+        // posts, so the preview has to answer for the button where it *will* be. Asking
+        // from where it currently sits gave a different pair of blinds than the deal
+        // produced — the preview promising one thing and doing another is exactly the
+        // guessing this whole step exists to remove. Same reason the broke seats come
+        // out first: the preview once promised a small blind from a seat with no chips.
+        const dealt = this.tableAsDealt(state);
+        const buttonIndex = HoldemState.buttonSeatForDeal(dealt);
+        const asDealt = buttonIndex === dealt.dealerSeatIndex
+            ? dealt
+            : { ...dealt, dealerSeatIndex: buttonIndex };
+
+        const satOut = this.brokeSeats(state);
+        const { sbIndex, bbIndex, headsUp, manual } = HoldemState.getBlindSeats(asDealt);
+        if (sbIndex === null || bbIndex === null) return null;
+        return {
+            sbIndex, bbIndex, headsUp, manual: !!manual,
+            buttonIndex,
+            buttonMoves: buttonIndex !== state.dealerSeatIndex,
+            satOut,
+            smallBlind: this.round(state.smallBlind || 0),
+            bigBlind: this.round(state.bigBlind || 0),
+        };
+    },
+
+    // Does handing this seat chips also put them back in the game?
+    //
+    // At a real table those are one event, and here they were two: a busted player got
+    // their chips and stayed sat out, silently skipped hand after hand until somebody
+    // noticed and found "Deal in" in the seat menu. Nothing said so — the toast just
+    // read "Ben added $100".
+    //
+    // Not for a seat that was sat out while *holding* chips. That's a dealer who sat
+    // somebody out on purpose and is topping them up, and dealing them back in would be
+    // the tool guessing at something it wasn't told. Only a seat with no stack of its
+    // own: busted at zero, or a chair being bought into for the first time.
+    //
+    // Deliberately reads player.stack rather than stackOf(), which substitutes the
+    // table's starting stack for a seat that has none — the question here is what this
+    // seat was actually recorded as holding.
+    buyInDealsThemIn(player) {
+        if (!player || player.inHand) return false;
+        const own = player.stack;
+        const recorded = own !== null && own !== undefined && String(own).trim() !== "";
+        return !recorded || Number(own) <= this.EPSILON_CHIPS;
+    },
+
+    // "bet" or "raise" — what putting more in is actually called right now.
+    //
+    // A wager into a pot nobody has wagered into is a bet; everything after that is a
+    // raise. The bar decided this from what the acting player still owes, which gets
+    // the big blind's option backwards: they owe nothing, so it offered "Bet", but
+    // their own blind is a live bet and putting more in is a raise. It gets the other
+    // half wrong too — the raise pad said "Raise to" for an opening bet on the flop,
+    // and wrote "Ann's raise to $10" into the undo control for it.
+    //
+    // The arithmetic was always right (minRaiseTo returns two big blinds for the big
+    // blind's option and one for an opening bet). This is only what it's called, which
+    // for a tool a dealer announces the action from is not a small thing.
+    wagerVerb(state) {
+        return (state.currentBet || 0) > this.EPSILON_CHIPS ? "raise" : "bet";
+    },
+
+    committed(player) {
+        return this.round(player.committed || 0);
+    },
+
+    // Everything this seat has put in across the whole hand, including the street
+    // still in progress.
+    handTotal(player) {
+        return this.round((Number(player.amountOverride) || 0) + this.committed(player));
+    },
+
+    // Never below zero. A seat can't have negative chips in front of it, and a typo in
+    // the stack field used to come back as-is — which then flowed into putIn(), where
+    // `Math.min(amount, -50)` moves a negative amount and *adds* chips to the table.
+    stackOf(state, player) {
+        const own = player.stack;
+        if (own !== null && own !== undefined && String(own).trim() !== "") {
+            return Math.max(0, this.round(own));
+        }
+        const fallback = Number(state.defaultStack);
+        return Number.isNaN(fallback) ? 0 : Math.max(0, this.round(fallback));
+    },
+
+    toCall(state, player) {
+        return Math.max(0, this.round((state.currentBet || 0) - this.committed(player)));
+    },
+
+    // A raise has to at least match the last one; before any raise, the big blind
+    // is the yardstick.
+    minRaiseTo(state) {
+        const increment = this.round(state.lastRaiseSize || state.bigBlind || 0);
+        return this.round((state.currentBet || 0) + (increment || 1));
+    },
+
+    potSoFar(state) {
+        return this.round(
+            state.seats.reduce((sum, p) => sum + this.handTotal(p), 0)
+        );
+    },
+
+    // ---- Moving the action ----
+
+    nextLiveIndex(state, fromIndex) {
+        const count = state.seatCount;
+        for (let step = 1; step <= count; step++) {
+            const index = this.seatAt(state, fromIndex, step);
+            const player = state.seats[index];
+            if (player.inHand && !player.folded) return index;
+        }
+        return null;
+    },
+
+    // Who the dealer asks next. A player who is all-in is still in the hand and still
+    // wins pots, but has no decision left, so the action passes over them.
+    nextToAct(state, fromIndex) {
+        const count = state.seatCount;
+        for (let step = 1; step <= count; step++) {
+            const index = this.seatAt(state, fromIndex, step);
+            const player = state.seats[index];
+            if (player.inHand && !player.folded && this.stackOf(state, player) > this.EPSILON_CHIPS) return index;
+        }
+        return null;
+    },
+
+    // A player still in the hand with chips in the pot and nothing left behind. This is
+    // the same stack test nextToAct uses to pass over them, which is the point: the
+    // seat the felt marks all-in is exactly the seat the dealer will never be asked to
+    // act on again.
+    //
+    // The "chips in the pot" half matters. A seat with an empty stack who hasn't put
+    // anything in is a busted player who shouldn't have been dealt in, not a player
+    // who moved all-in, and calling them all-in on the felt would be a lie.
+    isAllIn(state, player) {
+        if (!player || !player.inHand || player.folded) return false;
+        return this.handTotal(player) > this.EPSILON_CHIPS &&
+            this.stackOf(state, player) <= this.EPSILON_CHIPS;
+    },
+
+    // Which chair sits `step` places along in the direction of play. The table owns
+    // this — walking the seats is exactly where the button, the blinds and the action
+    // used to drift apart from each other, so there is one implementation of it.
+    seatAt(state, fromIndex, step) {
+        return HoldemState.nextSeatIndex(state, fromIndex, step);
+    },
+
+    // A street is done when everyone still live has either matched the bet or has
+    // no chips left to argue with, and everyone has had a turn since the last raise.
+    isStreetComplete(state) {
+        const live = this.liveSeats(state);
+        if (live.length <= 1) return true;
+
+        const unsettled = live.filter(s => {
+            const allIn = this.stackOf(state, s.player) <= 0;
+            const matched = this.toCall(state, s.player) <= 0;
+            return !allIn && (!matched || !s.player.hasActed);
+        });
+        return unsettled.length === 0;
+    },
+
+    // ---- Actions ----
+
+    // Moves `amount` from a seat's stack into the middle for this street. Returns
+    // what actually moved, which is less than asked for if it puts them all-in.
+    putIn(state, index, amount) {
+        const player = state.seats[index];
+        const stack = this.stackOf(state, player);
+        const moved = this.round(Math.min(Math.max(0, amount), stack));
+
+        player.stack = this.round(stack - moved);
+        player.committed = this.round(this.committed(player) + moved);
+        return moved;
+    },
+
+    fold(state, index) {
+        state.seats[index].folded = true;
+        state.seats[index].hasActed = true;
+        this.passAction(state, index);
+    },
+
+    check(state, index) {
+        state.seats[index].hasActed = true;
+        this.passAction(state, index);
+    },
+
+    call(state, index) {
+        const player = state.seats[index];
+        this.putIn(state, index, this.toCall(state, player));
+        player.hasActed = true;
+        this.passAction(state, index);
+    },
+
+    // `total` is what the seat's street commitment becomes — "raise to", the way a
+    // dealer says it out loud, not "raise by".
+    raiseTo(state, index, total) {
+        const player = state.seats[index];
+        const target = this.round(total);
+        const delta = this.round(target - this.committed(player));
+        const moved = this.putIn(state, index, delta);
+        const newBet = this.committed(player);
+        const previousBet = state.currentBet || 0;
+
+        if (newBet > previousBet) {
+            const increase = this.round(newBet - previousBet);
+            // What a full raise would have had to be: at least as much again as the
+            // last one, or the big blind if there hasn't been a raise yet.
+            const fullRaise = this.round(state.lastRaiseSize || state.bigBlind || 0);
+            const isFullRaise = increase >= fullRaise - this.EPSILON_CHIPS;
+
+            state.currentBet = newBet;
+
+            if (isFullRaise) {
+                state.lastRaiseSize = increase;
+                // A real raise reopens the action: everyone else owes a response again.
+                state.seats.forEach((p, i) => {
+                    if (i !== index && p.inHand && !p.folded) p.hasActed = false;
+                });
+            }
+            // Otherwise this is a short all-in — somebody with less than a full raise
+            // left shoving it in. The most misread rule in poker: it does *not* reopen
+            // the betting to anyone who has already acted. They owe the difference or
+            // they fold; they don't get to raise again because a short stack happened
+            // to be between them. Players yet to act keep their full rights, which
+            // they do here because their hasActed is already false.
+            //
+            // lastRaiseSize deliberately isn't lowered either, or the next legal raise
+            // would be computed off the short amount and come out too small.
+        }
+
+        player.hasActed = true;
+        this.passAction(state, index);
+        return moved;
+    },
+
+    allIn(state, index) {
+        const player = state.seats[index];
+        return this.raiseTo(state, index, this.round(this.committed(player) + this.stackOf(state, player)));
+    },
+
+    passAction(state, index) {
+        state.actingSeatIndex = this.isStreetComplete(state) ? null : this.nextToAct(state, index);
+    },
+
+    // ---- Street and hand boundaries ----
+
+    // Pulls whatever is in front of the players into their hand totals. Anything that
+    // reads a seat's contribution — the pot wizard above all — has to run after this,
+    // or it will price the pot without the chips sitting on the current street.
+    sweepToHandTotals(state) {
+        state.seats.forEach(player => {
+            const moved = this.committed(player);
+            if (moved > 0) {
+                player.amountOverride = this.round((Number(player.amountOverride) || 0) + moved);
+            }
+            player.committed = 0;
+            player.hasActed = false;
+        });
+    },
+
+    // Sweeps the street's chips into each seat's hand total and opens the next one.
+    closeStreet(state) {
+        this.sweepToHandTotals(state);
+
+        state.currentBet = 0;
+        state.lastRaiseSize = 0;
+
+        const nextStreetIndex = this.STREETS.indexOf(state.street || "preflop") + 1;
+        state.street = this.STREETS[nextStreetIndex] || "river";
+
+        // It takes two players with chips to have a bet. Once everyone left is all-in
+        // the rest of the board is just dealt out.
+        if (!this.canStillBet(state)) {
+            state.actingSeatIndex = null;
+            return;
+        }
+
+        // After the flop the first live player left of the button acts — which heads-up
+        // is the big blind, since the button is the small blind. Naming the big blind
+        // directly also covers a button parked on a seat nobody is sitting in, and it
+        // still has to be someone with chips left to bet.
+        const { bbIndex, headsUp } = HoldemState.getBlindSeats(state);
+        const bigBlindCanAct =
+            headsUp &&
+            bbIndex !== null &&
+            !state.seats[bbIndex].folded &&
+            this.stackOf(state, state.seats[bbIndex]) > this.EPSILON_CHIPS;
+
+        state.actingSeatIndex = bigBlindCanAct
+            ? bbIndex
+            : this.nextToAct(state, state.dealerSeatIndex);
+    },
+
+    isHandOver(state) {
+        return this.liveSeats(state).length <= 1;
+    },
+
+    // Players still in the hand who have chips left to put in. Fewer than two of them
+    // means the betting is finished even though the hand isn't.
+    seatsWithChips(state) {
+        return this.liveSeats(state).filter(s => this.stackOf(state, s.player) > this.EPSILON_CHIPS);
+    },
+
+    EPSILON_CHIPS: Money.EPSILON,
+
+    canStillBet(state) {
+        return this.liveSeats(state).length > 1 && this.seatsWithChips(state).length > 1;
+    },
+
+    // True when the hand is still live but nobody can bet again — the dealer is just
+    // running the board out.
+    isRunningOut(state) {
+        // Only while a hand is actually being played. Before the deal, a table of
+        // busted players who haven't rebought looks exactly like a table of all-ins to
+        // this test, and the bar was announcing a run-out over a felt with no cards and
+        // no chips on it.
+        if (!state.bettingOpen) return false;
+        return this.liveSeats(state).length > 1 && !this.canStillBet(state);
+    },
+
+    // True while nothing has happened in this hand except the blinds going in. Up to
+    // that point the dealer can still move the button or rename the blinds and have
+    // it cost nothing — which is the state a home game spends a lot of time in,
+    // arguing about whose turn it is before the cards come out.
+    onlyBlindsIn(state) {
+        return (state.street || "preflop") === "preflop" && state.seats.every(p => !p.hasActed);
+    },
+
+    // Pulls the blinds back off the table and posts them again from wherever the
+    // button and the blind assignment now say they belong. Refunding first is what
+    // keeps the chip count straight when the button gets passed round three or four
+    // times before anybody is happy with it.
+    repostBlinds(state) {
+        state.seats.forEach(player => {
+            const back = this.committed(player);
+            if (back > 0) player.stack = this.round(this.stackOf(state, player) + back);
+            player.committed = 0;
+            player.hasActed = false;
+        });
+        this.beginHand(state);
+    },
+
+    // Deals a fresh betting round: blinds posted, action to the seat after the big
+    // blind, which is where a dealer expects to be looking when the cards go out.
+    //
+    // Called when the dealer says the table is ready, not automatically when the
+    // previous hand ends — everything before this point is setup, where seats and the
+    // button can move freely because no money has been committed.
+    beginHand(state) {
+        state.bettingOpen = true;
+        state.street = "preflop";
+        state.currentBet = 0;
+        state.lastRaiseSize = 0;
+
+        // Deal around anyone with no chips, before anything else reads the table.
+        //
+        // A busted player who hasn't rebought used to be dealt in anyway, and the
+        // result was a hand nobody could finish: the table promised a small blind from
+        // a seat with nothing to post it with, took it from nobody, put the action on
+        // the big blind with only their own money in front of them, and announced
+        // "3 players — all-in, running out the board" before a card was dealt.
+        //
+        // Sitting them out is what a dealer does. Seat, name and buy-in record are
+        // untouched, so dealing them back in is one tap when they buy chips.
+        this.brokeSeats(state).forEach(index => {
+            state.seats[index].inHand = false;
+            state.seats[index].folded = false;
+        });
+
+        // Position is read off the button all through the hand, so it has to be on
+        // somebody before the blinds are worked out — not on the empty seat 1 a
+        // brand-new table starts on.
+        HoldemState.ensureButtonOnPlayer(state);
+
+        state.seats.forEach(player => {
+            player.committed = 0;
+            player.hasActed = false;
+        });
+
+        const sb = Number(state.smallBlind) || 0;
+        const bb = Number(state.bigBlind) || 0;
+        const { sbIndex, bbIndex, headsUp } = HoldemState.getBlindSeats(state);
+
+        if (sbIndex === null || bbIndex === null) {
+            state.currentBet = 0;
+            state.actingSeatIndex = null;
+            return;
+        }
+
+        if (sb > 0) this.putIn(state, sbIndex, sb);
+        if (bb > 0) this.putIn(state, bbIndex, bb);
+
+        state.currentBet = this.round(Math.max(this.committed(state.seats[sbIndex]), this.committed(state.seats[bbIndex])));
+        state.lastRaiseSize = bb || 0;
+
+        // Heads-up the button is the small blind and acts first before the flop; with
+        // three or more it's the seat after the big blind. Either way, a blind big
+        // enough to put that player all-in leaves them nothing to decide.
+        state.actingSeatIndex = headsUp
+            ? (this.stackOf(state, state.seats[sbIndex]) > this.EPSILON_CHIPS ? sbIndex : this.nextToAct(state, sbIndex))
+            : this.nextToAct(state, bbIndex);
+    },
+
+    // Winners get their share put back in front of them.
+    creditWinnings(state, payouts) {
+        payouts.forEach(payout => {
+            const player = state.seats.find(p => p.id === payout.id);
+            if (!player) return;
+            player.stack = this.round(this.stackOf(state, player) + payout.amount);
+        });
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = Betting;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/cardPicker.js

@@ -0,0 +1,131 @@
+// Tap a card instead of typing it.
+//
+// Typing "AH" into a two-character box is fine at a desk and miserable at a table:
+// it needs a keyboard, it accepts nonsense like "ZZ", and it happily lets the same
+// card land in two players' hands. The picker is one tap per card, greys out cards
+// already dealt somewhere else at the table, and stores exactly the same two-character
+// string the rest of the tool has always read.
+const CardPicker = {
+    RANKS: ["A", "K", "Q", "J", "T", "9", "8", "7", "6", "5", "4", "3", "2"],
+    SUITS: [
+        { code: "S", symbol: "♠", red: false },
+        { code: "H", symbol: "♥", red: true },
+        { code: "D", symbol: "♦", red: true },
+        { code: "C", symbol: "♣", red: false },
+    ],
+
+    state: null,
+    hooks: null,
+    seatIndex: null,
+    cardIndex: 0,
+
+    open(state, hooks, seatIndex, cardIndex) {
+        this.state = state;
+        this.hooks = hooks;
+        this.seatIndex = seatIndex;
+        this.cardIndex = cardIndex;
+        this.render();
+        document.getElementById("cardPickerOverlay").hidden = false;
+    },
+
+    close() {
+        document.getElementById("cardPickerOverlay").hidden = true;
+    },
+
+    // Every card sitting in front of anyone else. The slot being edited is excluded,
+    // so re-picking the card that's already there isn't treated as a duplicate.
+    cardsInUse() {
+        const used = new Map();
+        this.state.seats.forEach((player, seat) => {
+            (player.cards || []).forEach((card, slot) => {
+                if (!card) return;
+                if (seat === this.seatIndex && slot === this.cardIndex) return;
+                used.set(card.toUpperCase(), HoldemState.displayName(player, seat));
+            });
+        });
+        return used;
+    },
+
+    assign(card) {
+        const player = this.state.seats[this.seatIndex];
+        player.cards[this.cardIndex] = card;
+        this.hooks.onPick(this.seatIndex, this.cardIndex, card);
+
+        // Straight on to the second card — a dealer picking hole cards is always
+        // picking two, and making them re-open the picker doubles the taps.
+        if (this.cardIndex === 0 && !player.cards[1]) {
+            this.cardIndex = 1;
+            this.render();
+            return;
+        }
+        this.close();
+    },
+
+    clearSlot() {
+        const player = this.state.seats[this.seatIndex];
+        player.cards[this.cardIndex] = "";
+        this.hooks.onPick(this.seatIndex, this.cardIndex, "");
+        this.render();
+    },
+
+    render() {
+        const player = this.state.seats[this.seatIndex];
+        const used = this.cardsInUse();
+
+        document.getElementById("cardPickerTitle").textContent =
+            `${HoldemState.displayName(player, this.seatIndex)} — card ${this.cardIndex + 1}`;
+
+        // Which slot the next tap fills, switchable without closing the sheet.
+        const slots = document.getElementById("cardPickerSlots");
+        slots.innerHTML = "";
+        [0, 1].forEach(slot => {
+            const btn = document.createElement("button");
+            btn.type = "button";
+            btn.className = "pickerSlot";
+            btn.classList.toggle("active", slot === this.cardIndex);
+            const value = player.cards[slot] || "";
+            btn.textContent = value || "—";
+            btn.classList.toggle("cardRed", /[HD]$/i.test(value));
+            btn.addEventListener("click", () => {
+                this.cardIndex = slot;
+                this.render();
+            });
+            slots.appendChild(btn);
+        });
+
+        const grid = document.getElementById("cardPickerGrid");
+        grid.innerHTML = "";
+        this.RANKS.forEach(rank => {
+            this.SUITS.forEach(suit => {
+                const card = `${rank}${suit.code}`;
+                const takenBy = used.get(card);
+
+                const btn = document.createElement("button");
+                btn.type = "button";
+                btn.className = "pickerCard";
+                btn.classList.toggle("cardRed", suit.red);
+                btn.disabled = !!takenBy;
+                if (takenBy) btn.title = `Already dealt to ${takenBy}`;
+                if ((player.cards[this.cardIndex] || "").toUpperCase() === card) {
+                    btn.classList.add("selected");
+                }
+
+                const rankEl = document.createElement("span");
+                rankEl.className = "pickerRank";
+                rankEl.textContent = rank;
+                const suitEl = document.createElement("span");
+                suitEl.className = "pickerSuit";
+                suitEl.textContent = suit.symbol;
+                btn.appendChild(rankEl);
+                btn.appendChild(suitEl);
+
+                btn.addEventListener("click", () => this.assign(card));
+                grid.appendChild(btn);
+            });
+        });
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = CardPicker;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/feedback.js

@@ -0,0 +1,115 @@
+// Toasts and confirmation dialogs, so the table never has to fall back on the
+// browser's own alert boxes. A system confirm() steals focus, looks nothing like
+// the rest of the page, and on a phone it's a full-screen interruption — all of
+// which is a bad trade for a dealer trying to keep a game moving.
+
+// A short-lived message at the bottom of the screen, optionally with one action
+// (in practice: Undo). Only one is ever on screen; a second replaces the first.
+const Toast = {
+    DEFAULT_DURATION_MS: 8000,
+    timer: null,
+
+    show(message, options = {}) {
+        const host = document.getElementById("toastHost");
+        if (!host) return;
+
+        this.dismiss();
+
+        const toast = document.createElement("div");
+        toast.className = "toast";
+        toast.setAttribute("role", "status");
+
+        const text = document.createElement("span");
+        text.className = "toastText";
+        text.textContent = message;
+        toast.appendChild(text);
+
+        if (options.actionLabel && options.onAction) {
+            const action = document.createElement("button");
+            action.type = "button";
+            action.className = "toastAction";
+            action.textContent = options.actionLabel;
+            action.addEventListener("click", () => {
+                this.dismiss();
+                options.onAction();
+            });
+            toast.appendChild(action);
+        }
+
+        const close = document.createElement("button");
+        close.type = "button";
+        close.className = "toastClose";
+        close.setAttribute("aria-label", "Dismiss");
+        close.textContent = "✕";
+        close.addEventListener("click", () => this.dismiss());
+        toast.appendChild(close);
+
+        host.appendChild(toast);
+        // Next frame, so the entrance transition actually runs.
+        requestAnimationFrame(() => toast.classList.add("toastVisible"));
+
+        this.timer = setTimeout(
+            () => this.dismiss(),
+            options.duration || this.DEFAULT_DURATION_MS
+        );
+    },
+
+    dismiss() {
+        if (this.timer) {
+            clearTimeout(this.timer);
+            this.timer = null;
+        }
+        const host = document.getElementById("toastHost");
+        if (host) host.innerHTML = "";
+    },
+};
+
+// Styled stand-in for confirm(). Resolves true if the dealer goes through with it.
+const Dialog = {
+    confirm({ title, message, confirmLabel = "Confirm", cancelLabel = "Cancel", danger = false }) {
+        return new Promise(resolve => {
+            const overlay = document.getElementById("confirmOverlay");
+            const modal = overlay.querySelector("#confirmModal");
+            overlay.querySelector("#confirmTitle").textContent = title;
+            overlay.querySelector("#confirmMessage").textContent = message;
+
+            const confirmBtn = overlay.querySelector("#confirmAcceptBtn");
+            const cancelBtn = overlay.querySelector("#confirmCancelBtn");
+            confirmBtn.textContent = confirmLabel;
+            cancelBtn.textContent = cancelLabel;
+            confirmBtn.classList.toggle("holdemBtnDanger", danger);
+            confirmBtn.classList.toggle("holdemBtnAccent", !danger);
+
+            const finish = result => {
+                overlay.hidden = true;
+                confirmBtn.removeEventListener("click", onAccept);
+                cancelBtn.removeEventListener("click", onCancel);
+                overlay.removeEventListener("click", onBackdrop);
+                document.removeEventListener("keydown", onKey);
+                resolve(result);
+            };
+            const onAccept = () => finish(true);
+            const onCancel = () => finish(false);
+            const onBackdrop = e => {
+                if (e.target === overlay) finish(false);
+            };
+            const onKey = e => {
+                if (e.key === "Escape") finish(false);
+                if (e.key === "Enter") finish(true);
+            };
+
+            confirmBtn.addEventListener("click", onAccept);
+            cancelBtn.addEventListener("click", onCancel);
+            overlay.addEventListener("click", onBackdrop);
+            document.addEventListener("keydown", onKey);
+
+            overlay.hidden = false;
+            modal.focus();
+            confirmBtn.focus();
+        });
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = { Toast, Dialog };
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/handHistoryExport.js

@@ -0,0 +1,105 @@
+// Turns the in-memory hand history into a CSV file the dealer can download for a
+// paper trail — a house manager or a disputed chip count needs something that
+// outlives the browser tab, not just a scrollable panel in the sidebar.
+const HandHistoryExport = {
+    csvField(value) {
+        const str = String(value ?? "");
+        return /[",\n]/.test(str) ? `"${str.replace(/"/g, '""')}"` : str;
+    },
+
+    formatTimestamp(timestamp) {
+        try {
+            return new Date(timestamp).toLocaleString();
+        } catch {
+            return "";
+        }
+    },
+
+    // Money columns go in as bare numbers. Written as "$1,250,000.00" they import as
+    // text, so the one thing anybody opens this file to do — total a column and see
+    // who owes what — doesn't work without cleaning every cell first. The commas were
+    // quoted correctly, so the file parsed; it just wouldn't add up.
+    toCsv(handHistory, standings = []) {
+        const rows = [["Hand #", "Time", "Pot", "Payouts"]];
+        // handHistory is stored newest-first; the export reads better oldest-first.
+        [...handHistory].reverse().forEach(entry => {
+            const payouts = (entry.payouts || [])
+                .map(p => `${p.label}: ${Money.format(p.amount)}`)
+                .join("; ");
+            rows.push([
+                entry.handNumber,
+                this.formatTimestamp(entry.timestamp),
+                Money.forSheet(entry.pot),
+                payouts,
+            ]);
+        });
+
+        // The settle-up numbers go in the same file as the hands they came from, so a
+        // dealer handing over one export isn't asked for a second one at cash-out.
+        if (standings.length > 0) {
+            rows.push([]);
+            rows.push(["Session Standings"]);
+            // Bought in and chips now are what a cash-out is settled from; paid in and
+            // won describe the hands. Both belong in the file the dealer hands over.
+            rows.push(["Player", "Paid In", "Won", "Net", "Bought In", "Chips Now", "Up/Down"]);
+            standings.forEach(row => {
+                rows.push([
+                    row.name,
+                    Money.forSheet(row.in),
+                    Money.forSheet(row.won),
+                    Money.forSheet(row.net),
+                    Money.forSheet(row.boughtIn || 0),
+                    Money.forSheet(row.chipsNow || 0),
+                    Money.forSheet(row.cashPosition || 0),
+                ]);
+            });
+
+            // And the answer the standings are read to get to. Whoever opens this file
+            // wants the payment list, not to redo the arithmetic in a spreadsheet.
+            const plan = SettleUp.plan(standings);
+            if (plan.payments.length > 0) {
+                rows.push([]);
+                rows.push(["Settle Up"]);
+                rows.push(["Pays", "Receives", "Amount"]);
+                plan.payments.forEach(payment => {
+                    rows.push([payment.from, payment.to, Money.forSheet(payment.amount)]);
+                });
+                if (!plan.balanced) {
+                    // The file is the paper trail, so the caveat travels with it rather
+                    // than living only in a sidebar nobody exported.
+                    rows.push([
+                        plan.shortBy > 0
+                            ? `Unpaid: ${Money.forSheet(plan.shortBy)} — more chips in play than cash taken`
+                            : `Unclaimed: ${Money.forSheet(plan.overBy)} — more cash taken than chips in play`,
+                    ]);
+                }
+            }
+        }
+
+        return rows.map(row => row.map(f => this.csvField(f)).join(",")).join("\r\n");
+    },
+
+    fileName() {
+        const now = new Date();
+        const pad = n => String(n).padStart(2, "0");
+        const stamp = `${now.getFullYear()}-${pad(now.getMonth() + 1)}-${pad(now.getDate())}-${pad(now.getHours())}${pad(now.getMinutes())}`;
+        return `holdem-hand-history-${stamp}.csv`;
+    },
+
+    download(handHistory, standings = []) {
+        const csv = this.toCsv(handHistory, standings);
+        const blob = new Blob([csv], { type: "text/csv;charset=utf-8;" });
+        const url = URL.createObjectURL(blob);
+        const link = document.createElement("a");
+        link.href = url;
+        link.download = this.fileName();
+        document.body.appendChild(link);
+        link.click();
+        document.body.removeChild(link);
+        URL.revokeObjectURL(url);
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = HandHistoryExport;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/main.js

@@ -0,0 +1,502 @@
+document.addEventListener("DOMContentLoaded", () => {
+    const state = HoldemState.load();
+
+    // Focus, Tab-trapping and Escape for every overlay, wired once by watching the
+    // `hidden` attribute they all already toggle.
+    Modal.mount();
+
+    // Undo works by swapping the whole table back to a snapshot. `state` is handed out
+    // by reference to every module at mount time, so it has to be refilled in place —
+    // reassigning the variable would leave the renderer and the betting bar pointing at
+    // the old object and quietly ignoring the undo.
+    const snapshotState = () => JSON.parse(JSON.stringify(state));
+
+    const restoreState = snapshot => {
+        Object.keys(state).forEach(key => delete state[key]);
+        Object.assign(state, snapshot);
+        HoldemState.save(state);
+        Render.renderAll();
+    };
+
+    // A gesture on a seat is a shortcut for something the dealer could do the long
+    // way, so each one is undoable the same way the header buttons are.
+    const seatAction = (index, message, mutate) => {
+        const snapshot = snapshotState();
+        mutate(state.seats[index], index);
+        HoldemState.save(state);
+        Render.renderAll();
+
+        Toast.show(message, {
+            actionLabel: "Undo",
+            onAction: () => {
+                restoreState(snapshot);
+                Toast.show("Undone.", { duration: 2500 });
+            },
+            duration: 6000,
+        });
+    };
+
+    const nameOf = index => HoldemState.displayName(state.seats[index], index);
+
+    const hooks = {
+        save: s => HoldemState.save(s),
+        rerender: () => Render.renderAll(),
+
+        onSeatDoubleTap: index => {
+            const player = state.seats[index];
+            if (!player.inHand) return;
+            if (player.folded) {
+                seatAction(index, `${nameOf(index)} is back in the hand.`, p => { p.folded = false; });
+                return;
+            }
+            seatAction(index, `${nameOf(index)} folds.`, () => {
+                if (state.actingSeatIndex === index) Betting.fold(state, index);
+                else player.folded = true;
+            });
+        },
+
+        onSeatLongPress: index => SeatMenu.open(state, seatMenuHooks, index),
+        onGiveButton: index => seatMenuHooks.makeDealer(index),
+    };
+
+    const seatMenuHooks = {
+        fold: index => hooks.onSeatDoubleTap(index),
+        unfold: index => seatAction(index, `${nameOf(index)} is back in the hand.`, p => { p.folded = false; }),
+        allIn: index => seatAction(index, `${nameOf(index)} is all-in.`, () => Betting.allIn(state, index)),
+        toggleDealtIn: index => {
+            const player = state.seats[index];
+            const dealtIn = player.inHand;
+            const handRunning = !Betting.onlyBlindsIn(state) || Betting.potSoFar(state) > 0;
+            const alreadyIn = Betting.handTotal(player);
+
+            // Somebody walking away mid-hand doesn't get their chips back — they're
+            // dead money the winner collects. Say so, because the pot total pointedly
+            // does not go down and a dealer needs to know that's deliberate.
+            const message = dealtIn
+                ? (alreadyIn > 0
+                    ? `${nameOf(index)} is out — their ${Money.format(alreadyIn)} stays in the pot.`
+                    : `${nameOf(index)} sits out.`)
+                : (handRunning
+                    ? `${nameOf(index)} is in from the next hand.`
+                    : `${nameOf(index)} is dealt in.`);
+
+            seatAction(index, message, p => {
+                p.inHand = !dealtIn;
+                if (!p.inHand) {
+                    // Their chips stay put; only the fold flag is cleared, since being
+                    // out of the hand already covers not winning it.
+                    p.folded = false;
+                    if (state.actingSeatIndex === index) Betting.passAction(state, index);
+                } else if (handRunning) {
+                    // Joining a hand already in progress means sitting this one out —
+                    // you can't buy into a pot you haven't been paying for. `folded`
+                    // is exactly that state, and the next hand clears it.
+                    p.folded = true;
+                }
+            });
+        },
+
+        // Two players change chairs. Undoable like every other seat action, because a
+        // swap is easy to aim wrong and the seats look alike at a glance.
+        swapSeats: (from, to) => {
+            const movedName = nameOf(from);
+            const intoName = nameOf(to);
+            const wasEmpty = Render.isEmptySeat(state.seats[to]);
+            runUndoable(
+                wasEmpty
+                    ? `${movedName} moved to seat ${to + 1}.`
+                    : `${movedName} and ${intoName} changed seats.`,
+                () => HoldemState.swapSeats(state, from, to));
+        },
+
+        makeDealer: index => {
+            // Before the deal there's nothing posted, so this is just moving a marker.
+            // After it, the blinds have to follow the button or the badges and the
+            // money disagree — but that's a real thing happening to real chips, and
+            // the dealer gets told rather than finding out later.
+            const willRepost = state.bettingOpen && Betting.onlyBlindsIn(state) &&
+                HoldemState.unresolvedContributions(state) > Betting.EPSILON_CHIPS;
+
+            seatAction(index, willRepost
+                ? `Button on ${nameOf(index)} — blinds taken back and re-posted.`
+                : `Button on ${nameOf(index)}.`, () => {
+                state.dealerSeatIndex = index;
+                if (willRepost) Betting.repostBlinds(state);
+            });
+        },
+
+        assignBlind: (index, which) => {
+            const blinds = HoldemState.getBlindSeats(state);
+            const other = which === "sb" ? blinds.bbIndex : blinds.sbIndex;
+            // Naming one blind pins the other where it already is, so the dealer only
+            // has to state the part they're changing. If that would land both on one
+            // player, the other blind moves to the next seat along.
+            let partner = other !== null && other !== undefined && other !== index
+                ? other
+                : Betting.nextLiveIndex(state, index);
+            if (partner === index || partner === null) partner = Betting.nextLiveIndex(state, index);
+
+            const label = which === "sb" ? "small blind" : "big blind";
+            seatAction(index, `${nameOf(index)} posts the ${label}.`, () => {
+                state.blindOverride = which === "sb"
+                    ? { sbIndex: index, bbIndex: partner }
+                    : { sbIndex: partner, bbIndex: index };
+                if (Betting.onlyBlindsIn(state)) Betting.repostBlinds(state);
+            });
+        },
+
+        clearBlindOverride: () => seatAction(state.dealerSeatIndex, "Blinds follow the button again.", () => {
+            state.blindOverride = null;
+            if (Betting.onlyBlindsIn(state)) Betting.repostBlinds(state);
+        }),
+
+        editSeat: index => Render.toggleSeatEditor(index),
+
+        addChips: index => AddChips.open(state, index, (seatIndex, amount) => {
+            // Buying chips puts you back in the game — see Betting.buyInDealsThemIn.
+            const dealBackIn = Betting.buyInDealsThemIn(state.seats[seatIndex]);
+            const handRunning = !Betting.onlyBlindsIn(state) || Betting.potSoFar(state) > 0;
+
+            const message = `${nameOf(seatIndex)} added ${Money.format(amount)}` +
+                (dealBackIn
+                    ? handRunning ? " — in from the next hand." : " — dealt in."
+                    : ".");
+
+            seatAction(seatIndex, message, p => {
+                // Chips in front and cash in are different questions — the stack moves
+                // every hand, what they've handed over only moves when they buy.
+                p.stack = Money.round(Betting.stackOf(state, p) + amount);
+                p.buyIns = Money.round((Number(p.buyIns) || 0) + amount);
+
+                if (dealBackIn) {
+                    p.inHand = true;
+                    // Same rule "Deal in" follows: you can't buy into a pot you haven't
+                    // been paying for, and `folded` is exactly that state for one hand.
+                    p.folded = handRunning;
+                }
+            });
+        }),
+    };
+
+    Render.mount(state, hooks);
+
+    const openPotWizard = () => {
+        // Chips still in front of players belong in the pot being priced, so bank them
+        // before the wizard reads anyone's contribution.
+        Betting.sweepToHandTotals(state);
+        hooks.save(state);
+        Render.renderAll();
+
+        PotWizard.open(state, payouts => {
+            const paid = payouts.map(p => `${p.label} ${Money.format(p.amount)}`).join(", ");
+            runUndoable(paid ? `Paid ${paid}.` : "Hand closed with nothing to pay out.", () => {
+                if (payouts.length > 0) {
+                    HoldemState.recordHand(state, payouts);
+                    // Winnings go straight back in front of the player, so the next
+                    // hand's stacks are already right.
+                    Betting.creditWinnings(state, payouts);
+                }
+                // Settling a pot ends the hand; it doesn't start the next one. The
+                // table goes back to setup so people can sit down or cash out before
+                // any blinds are committed.
+                HoldemState.startNextHand(state);
+            });
+        });
+    };
+
+    // A short history of actions taken from the bar, so a misclicked Fold can be taken
+    // back — and the one before it, since a dealer usually notices a beat late. Kept in
+    // memory only: this is for the mistake you just made, not last night's hand.
+    const MAX_UNDO_STEPS = 12;
+    const actionHistory = [];
+
+    ActionBar.mount(state, {
+        save: hooks.save,
+        rerender: hooks.rerender,
+        resolvePot: openPotWizard,
+
+        beginAction: label => {
+            actionHistory.push({ label, snapshot: snapshotState() });
+            if (actionHistory.length > MAX_UNDO_STEPS) actionHistory.shift();
+        },
+
+        lastActionLabel: () => (actionHistory.length ? actionHistory[actionHistory.length - 1].label : null),
+
+        undoLast: () => {
+            const step = actionHistory.pop();
+            if (!step) return;
+            restoreState(step.snapshot);
+            Toast.show(`Took back ${step.label}.`, { duration: 2500 });
+        },
+    });
+
+    // Anything that ends the hand makes the per-action history meaningless — the
+    // snapshots refer to a hand that no longer exists.
+    const clearActionHistory = () => { actionHistory.length = 0; };
+
+    // Keyboard shortcuts press the very same buttons a dealer would tap, rather than
+    // calling the betting engine themselves — there's no second code path to drift out
+    // of step with what the bar is actually offering right now.
+    const pressInBar = selector => {
+        const btn = document.querySelector(`#actionBar ${selector}`);
+        if (!btn || btn.disabled) return false;
+        btn.click();
+        return true;
+    };
+
+    const quickRaiseButton = label =>
+        [...document.querySelectorAll("#actionBar .raiseQuickBtn")]
+            .find(b => b.querySelector(".actionBtnLabel").textContent === label);
+
+    Shortcuts.mount({
+        fold: () => pressInBar(".actionFold"),
+        checkOrCall: () => pressInBar(".actionCheck") || pressInBar(".actionCall"),
+        raise: () => pressInBar(".actionRaise"),
+        allIn: () => {
+            // Open the raise pad first if it isn't already, then take its All-in amount.
+            if (!document.querySelector("#actionBar .raisePad") && !pressInBar(".actionRaise")) return false;
+            const quick = quickRaiseButton("All-in");
+            if (!quick) return false;
+            quick.click();
+            return true;
+        },
+        // Enter confirms a raise if one is being entered, otherwise moves the hand on.
+        // Dealing is an advance too — Enter should carry a dealer through setup, deal,
+        // streets and showdown without reaching for the trackpad.
+        advance: () => pressInBar(".raiseConfirm") || pressInBar(".actionAdvance") || pressInBar(".actionDeal"),
+        undo: () => pressInBar(".actionUndo"),
+        cancel: () => pressInBar(".raiseCancel"),
+    });
+
+    // Moving to the next hand used to ask "are you sure?" every single time —
+    // the most-pressed button in a session, gated behind a system dialog. It now
+    // just happens, and the toast offers the way back for the few seconds anyone
+    // would notice a misclick. The snapshot is deliberately in-memory only: an
+    // undo is for the mistake you just made, not one from last night's session.
+    const runUndoable = (message, mutate) => {
+        const snapshot = snapshotState();
+        mutate();
+        // Starting or settling a hand invalidates the per-action history: those
+        // snapshots describe a hand that's over. The whole-step Undo below replaces it.
+        clearActionHistory();
+        hooks.save(state);
+        Render.renderAll();
+
+        Toast.show(message, {
+            actionLabel: "Undo",
+            onAction: () => {
+                restoreState(snapshot);
+                Toast.show("Undone.", { duration: 2500 });
+            },
+        });
+    };
+
+    // A seat that has anything of a player in it — a name, chips, cash in, or a hand
+    // in progress. Shrinking the table throws these away permanently, and it also
+    // orphans them in the session standings, where they keep their winnings but lose
+    // the stack and buy-in the settle-up is worked out from.
+    const seatHasSomeoneIn = player =>
+        !!(player.name && player.name.trim()) ||
+        player.inHand ||
+        (Number(player.stack) || 0) > 0 ||
+        (Number(player.buyIns) || 0) > 0 ||
+        (Number(player.amountOverride) || 0) > 0;
+
+    document.getElementById("seatCountInput").addEventListener("change", async e => {
+        const requested = Math.max(2, Math.min(24, Math.floor(Number(e.target.value)) || state.seatCount));
+        const losing = state.seats.slice(requested).filter(seatHasSomeoneIn);
+
+        if (losing.length > 0) {
+            const who = losing
+                .map((p, i) => HoldemState.displayName(p, requested + state.seats.slice(requested).indexOf(p)))
+                .join(", ");
+            const ok = await Dialog.confirm({
+                title: `Remove ${losing.length} ${losing.length === 1 ? "player" : "players"}?`,
+                message: `Going down to ${requested} seats takes ${who} off the table along with their chips and buy-ins, and their session totals stop adding up.`,
+                confirmLabel: "Remove them",
+                danger: true,
+            });
+            if (!ok) {
+                e.target.value = state.seatCount;
+                return;
+            }
+        }
+
+        runUndoable(`Table set to ${requested} seats.`, () => HoldemState.resizeSeats(state, requested));
+    });
+
+    document.getElementById("directionSelect").addEventListener("change", e => {
+        state.direction = e.target.value;
+        hooks.save(state);
+        Render.renderSeats();
+    });
+
+    document.getElementById("basePotInput").addEventListener("input", e => {
+        state.basePotAmount = e.target.value === "" ? null : Number(e.target.value);
+        hooks.save(state);
+        Render.renderAll();
+    });
+
+    document.getElementById("dedicatedDealerToggle").addEventListener("change", e => {
+        state.dedicatedDealer = e.target.checked;
+        hooks.save(state);
+        Render.renderSeats();
+        Render.renderTableHint();
+    });
+
+    document.getElementById("tableNotes").addEventListener("input", e => {
+        state.notes = e.target.value;
+        hooks.save(state);
+    });
+
+    document.getElementById("addChipColorBtn").addEventListener("click", () => {
+        state.chipLegend.push({
+            id: HoldemState.makeId("chip"),
+            color: "#888888",
+            value: 1,
+        });
+        hooks.save(state);
+        Render.renderAll();
+    });
+
+    document.getElementById("nextHandBtn").addEventListener("click", async () => {
+        // Moving on wipes every seat's contribution, so an unresolved pot is simply
+        // destroyed — measured at a four-handed table, pressing this with $8 in the
+        // middle took the table from 800 chips to 792, and the toast said nothing
+        // about it. Chips only ever leave this tool because a dealer meant them to.
+        const unresolved = HoldemState.unresolvedContributions(state);
+
+        if (unresolved > Betting.EPSILON_CHIPS) {
+            const ok = await Dialog.confirm({
+                title: `Throw away ${Money.format(unresolved)}?`,
+                message: "There's still money in the middle from this hand. Starting the next one takes it off the table without paying anybody — use Resolve Pot if somebody won it.",
+                confirmLabel: "Throw it away",
+                danger: true,
+            });
+            if (!ok) return;
+        }
+
+        // startNextHand moves the button on by one; say where it landed so the
+        // dealer can confirm the rotation without hunting for the badge.
+        const nextDealer = HoldemState.nextSeatIndex(state, state.dealerSeatIndex, 1);
+        const where = state.dedicatedDealer
+            ? `small blind on seat ${HoldemState.nextSeatIndex(state, nextDealer, 1) + 1}`
+            : `button on seat ${nextDealer + 1}`;
+        const discarded = unresolved > Betting.EPSILON_CHIPS
+            ? ` ${Money.format(unresolved)} taken off the table.`
+            : "";
+
+        runUndoable(`Next hand — ${where}. Seat the table, then deal.${discarded}`, () => {
+            HoldemState.startNextHand(state);
+        });
+    });
+
+    document.getElementById("resetTableBtn").addEventListener("click", async () => {
+        const ok = await Dialog.confirm({
+            title: "Reset the whole table?",
+            message: "Every seat, chip colour and note goes back to defaults. The hand history and session standings are cleared too.",
+            confirmLabel: "Reset table",
+            danger: true,
+        });
+        if (!ok) return;
+
+        HoldemState.clear();
+        Object.assign(state, HoldemState.createDefault());
+        clearActionHistory();
+        Render.mount(state, hooks);
+        Toast.show("Table reset.", { duration: 2500 });
+    });
+
+    // A pre-filled amount is a suggestion, so reaching for the box replaces it.
+    //
+    // Delegated from the document rather than wired per field: the raise pad, the
+    // add-chips sheet and the seat editor all build their inputs fresh every render,
+    // and a box added later should not have to remember to ask for this.
+    document.addEventListener("focusin", event => {
+        const field = event.target;
+        if (!Money.selectsOnFocus(field)) return;
+        if (!field.value) return;
+        // After the browser has finished placing its own caret, or it wins the race
+        // and the selection collapses again the moment the tap completes.
+        setTimeout(() => {
+            if (document.activeElement !== field) return;
+            try {
+                field.select();
+            } catch {
+                // A number input refuses setSelectionRange in some browsers; select()
+                // is the one that works on both, and if neither does the field is
+                // simply left as it was.
+            }
+        }, 0);
+    });
+
+    document.getElementById("resolvePotBtn").addEventListener("click", openPotWizard);
+
+    [
+        ["smallBlindInput", "smallBlind"],
+        ["bigBlindInput", "bigBlind"],
+        ["defaultStackInput", "defaultStack"],
+    ].forEach(([id, key]) => {
+        document.getElementById(id).addEventListener("input", e => {
+            state[key] = e.target.value === "" ? null : Number(e.target.value);
+            hooks.save(state);
+            Render.renderAll();
+        });
+    });
+
+    document.getElementById("closeSeatEditorBtn").addEventListener("click", () => Render.closeSeatEditor());
+
+    document.getElementById("addChipsConfirmBtn").addEventListener("click", () => AddChips.confirm());
+    document.getElementById("addChipsCancelBtn").addEventListener("click", () => AddChips.close());
+    document.getElementById("addChipsOverlay").addEventListener("click", e => {
+        if (e.target.id === "addChipsOverlay") AddChips.close();
+    });
+    document.getElementById("addChipsInput").addEventListener("keydown", e => {
+        if (e.key === "Enter") AddChips.confirm();
+    });
+
+    // Escape is Modal's job now, for this sheet and the five others that never had it.
+    const rulingsOverlay = document.getElementById("rulingsOverlay");
+    const closeRulings = () => { rulingsOverlay.hidden = true; };
+    document.getElementById("openRulingsBtn").addEventListener("click", () => { rulingsOverlay.hidden = false; });
+    document.getElementById("closeRulingsBtn").addEventListener("click", closeRulings);
+    rulingsOverlay.addEventListener("click", e => {
+        if (e.target === rulingsOverlay) closeRulings();
+    });
+
+    document.getElementById("seatMenuCancelBtn").addEventListener("click", () => SeatMenu.close());
+    document.getElementById("seatMenuOverlay").addEventListener("click", e => {
+        if (e.target.id === "seatMenuOverlay") SeatMenu.close();
+    });
+
+    document.getElementById("cardPickerCloseBtn").addEventListener("click", () => CardPicker.close());
+    document.getElementById("cardPickerClearBtn").addEventListener("click", () => CardPicker.clearSlot());
+    document.getElementById("cardPickerOverlay").addEventListener("click", e => {
+        if (e.target.id === "cardPickerOverlay") CardPicker.close();
+    });
+
+    document.getElementById("closePotWizardBtn").addEventListener("click", () => PotWizard.close());
+    document.getElementById("potWizardOverlay").addEventListener("click", e => {
+        if (e.target.id === "potWizardOverlay") PotWizard.close();
+    });
+
+    document.getElementById("clearHistoryBtn").addEventListener("click", async () => {
+        const ok = await Dialog.confirm({
+            title: "Clear the hand history?",
+            message: "This wipes every logged hand and the session standings, and puts the hand counter back to #1. Export first if anyone might want the numbers.",
+            confirmLabel: "Clear history",
+            danger: true,
+        });
+        if (!ok) return;
+
+        HoldemState.clearHistory(state);
+        hooks.save(state);
+        Render.renderAll();
+        Toast.show("Hand history cleared.", { duration: 2500 });
+    });
+
+    document.getElementById("exportHistoryBtn").addEventListener("click", () => {
+        if ((state.handHistory || []).length === 0) return;
+        HandHistoryExport.download(state.handHistory, HoldemState.sessionStandings(state));
+    });
+});

JoshHeaps.Net/wwwroot/js/casino/holdem/modal.js

@@ -0,0 +1,147 @@
+// Keyboard and screen-reader behaviour for every overlay in the tool, in one place.
+//
+// There are six of them — seat menu, card picker, add chips, rulings, pot wizard,
+// confirm — opened and closed by five different modules, and each one was missing
+// the same three things: focus never moved into the dialog, Tab walked straight out
+// of it into the page behind the scrim, and Escape did nothing (only the rulings
+// sheet handled it). Measured before this: 0 of 5 moved focus in, 5 of 5 leaked Tab,
+// 1 of 5 closed on Escape.
+//
+// Rather than patch that into five modules, this watches the `hidden` attribute every
+// overlay already toggles. Nothing else had to change, and an overlay added later
+// gets the same behaviour without anyone remembering to wire it up — which is the
+// failure this is fixing in the first place.
+const Modal = {
+    // `:not([hidden])` matters — a sheet that is itself hidden inside an open overlay
+    // must not be a Tab stop.
+    FOCUSABLE: [
+        "a[href]",
+        "button:not([disabled])",
+        'input:not([disabled]):not([type="hidden"])',
+        "select:not([disabled])",
+        "textarea:not([disabled])",
+        '[tabindex]:not([tabindex="-1"])',
+    ].join(","),
+
+    open: [],
+
+    mount() {
+        document.querySelectorAll('[id$="Overlay"]').forEach(overlay => this.watch(overlay));
+        // Capture phase: the dialog gets first refusal on Escape and Tab, before any
+        // table-level shortcut sees them.
+        document.addEventListener("keydown", e => this.onKeyDown(e), true);
+    },
+
+    watch(overlay) {
+        const sync = () => {
+            const isOpen = !overlay.hidden;
+            const known = this.open.some(entry => entry.overlay === overlay);
+            if (isOpen && !known) this.onOpened(overlay);
+            else if (!isOpen && known) this.onClosed(overlay);
+        };
+        new MutationObserver(sync).observe(overlay, { attributes: true, attributeFilter: ["hidden"] });
+        sync();
+    },
+
+    sheetOf(overlay) {
+        return overlay.querySelector('[role="dialog"], [role="alertdialog"]') || overlay.firstElementChild || overlay;
+    },
+
+    focusableIn(overlay) {
+        return [...overlay.querySelectorAll(this.FOCUSABLE)].filter(el => {
+            if (el.closest("[hidden]")) return false;
+            const rect = el.getBoundingClientRect();
+            return rect.width > 0 && rect.height > 0;
+        });
+    },
+
+    onOpened(overlay) {
+        const sheet = this.sheetOf(overlay);
+        // aria-modal is only true while the thing is actually open, so it's set here
+        // rather than baked into the markup.
+        if (sheet) sheet.setAttribute("aria-modal", "true");
+
+        this.open.push({ overlay, returnFocus: document.activeElement });
+
+        // Focus the first real control. A dialog that leaves focus on the button
+        // behind it reads, to a screen reader, as though nothing happened at all.
+        // Content-only sheets get focus on the sheet so the title is announced.
+        const focusable = this.focusableIn(overlay);
+        const target = focusable[0];
+        if (target) {
+            target.focus({ preventScroll: true });
+        } else if (sheet) {
+            if (!sheet.hasAttribute("tabindex")) sheet.setAttribute("tabindex", "-1");
+            sheet.focus({ preventScroll: true });
+        }
+    },
+
+    onClosed(overlay) {
+        const index = this.open.findIndex(entry => entry.overlay === overlay);
+        if (index === -1) return;
+        const [entry] = this.open.splice(index, 1);
+
+        const sheet = this.sheetOf(overlay);
+        if (sheet) sheet.removeAttribute("aria-modal");
+
+        // Put the dealer back where they were. Without this, closing the pot wizard
+        // drops focus to the top of the document and the next Tab starts from the
+        // page header.
+        const back = entry.returnFocus;
+        if (back && back.isConnected && typeof back.focus === "function") {
+            back.focus({ preventScroll: true });
+        }
+    },
+
+    topmost() {
+        return this.open.length ? this.open[this.open.length - 1] : null;
+    },
+
+    // Escape presses the dialog's own cancel/close button rather than just hiding the
+    // overlay, so whatever that button does — resolving the confirm promise, clearing
+    // the add-chips draft — still happens. Only if there isn't one does it hide the
+    // overlay directly.
+    dismiss(overlay) {
+        const closer = overlay.querySelector("[data-modal-close]");
+        if (closer) closer.click();
+        else overlay.hidden = true;
+    },
+
+    onKeyDown(event) {
+        const top = this.topmost();
+        if (!top) return;
+
+        if (event.key === "Escape") {
+            event.preventDefault();
+            event.stopPropagation();
+            this.dismiss(top.overlay);
+            return;
+        }
+
+        if (event.key !== "Tab") return;
+
+        // Keep Tab inside the dialog. Everything behind the scrim is unreachable by
+        // mouse, so letting the keyboard wander back there is a trap with no way out.
+        const focusable = this.focusableIn(top.overlay);
+        if (focusable.length === 0) {
+            event.preventDefault();
+            return;
+        }
+
+        const first = focusable[0];
+        const last = focusable[focusable.length - 1];
+        const active = document.activeElement;
+
+        if (event.shiftKey && (active === first || !top.overlay.contains(active))) {
+            event.preventDefault();
+            last.focus({ preventScroll: true });
+        } else if (!event.shiftKey && (active === last || !top.overlay.contains(active))) {
+            event.preventDefault();
+            first.focus({ preventScroll: true });
+        }
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = Modal;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/money.js

@@ -0,0 +1,133 @@
+// Shared money handling for every casino surface. Kept apart from the table's
+// rendering so the quick-split calculator can pull it in without dragging the whole
+// seat/chip UI along with it.
+//
+// Everything the dealer touches is money, and money is decimal, so every module used
+// to carry its own `Math.round(x * 100) / 100`. That's one rounding rule written out
+// sixteen times in six files, which is sixteen chances for one of them to drift.
+// It lives here now, and the modules that do arithmetic call these instead.
+const Money = {
+    // Half a cent. Chip comparisons need a tolerance: a stack that lands on
+    // 0.0000000001 after a split is empty as far as a dealer is concerned, and an
+    // exact `> 0` would treat that player as still having chips to bet.
+    EPSILON: 0.004,
+
+    // All money maths goes through cents, so 0.1 + 0.2 never reaches a payout.
+    toCents(amount) {
+        return Math.round((Number(amount) || 0) * 100);
+    },
+
+    fromCents(cents) {
+        return cents / 100;
+    },
+
+    round(amount) {
+        return this.toCents(amount) / 100;
+    },
+
+    // Cents only when there are cents.
+    //
+    // A chip game deals in whole numbers nearly all the time, and a trailing ".00"
+    // is two characters that say nothing — measured at ~22px, against the 64px a
+    // seat puck has to show a stack in. "$1,250,000.00" doesn't fit and wraps;
+    // "$1,250,000" does. Amounts that genuinely carry cents still show them, so a
+    // 25c-blind game reads exactly as it did.
+    format(amount) {
+        const value = Number(amount) || 0;
+        const hasCents = this.toCents(value) % 100 !== 0;
+        return `$${value.toLocaleString(undefined, {
+            minimumFractionDigits: hasCents ? 2 : 0,
+            maximumFractionDigits: 2,
+        })}`;
+    },
+
+    // The same amount for a spreadsheet rather than for a person: no currency symbol
+    // and no thousands separators, because those are what make a column of money
+    // import as text and refuse to add up.
+    forSheet(amount) {
+        return (this.toCents(amount) / 100).toFixed(2);
+    },
+
+    // The chips to actually push, for an amount.
+    //
+    // A payout figure is the answer to the arithmetic, not to the dealer's job: they
+    // still have to work out that $132 is two blacks, a green, a red and two whites
+    // while six people watch. The chip legend already knows the denominations.
+    //
+    // Largest first, which is greedy and therefore not optimal for an arbitrary set of
+    // values — but poker chips are not arbitrary. Every real set is canonical (each
+    // denomination divides the next: 1, 5, 25, 100, 500), and greedy is exactly optimal
+    // on those. A dealer who invents a 3-and-7 chip set gets a valid answer that might
+    // use one chip more than it had to.
+    //
+    // Anything the smallest chip can't make comes back as `remainder` rather than being
+    // rounded away: a 50c share in a game whose smallest chip is a dollar is a real
+    // problem for the dealer to solve, not a rounding error to hide.
+    chipBreakdown(amount, legend) {
+        let cents = this.toCents(amount);
+        if (cents <= 0) return { chips: [], remainder: 0 };
+
+        const values = (legend || [])
+            .map(chip => ({ chip, cents: this.toCents(chip.value) }))
+            .filter(entry => entry.cents > 0)
+            .sort((a, b) => b.cents - a.cents);
+
+        const chips = [];
+        values.forEach(entry => {
+            const count = Math.floor(cents / entry.cents);
+            if (count <= 0) return;
+            cents -= count * entry.cents;
+            chips.push({ value: this.fromCents(entry.cents), count, color: entry.chip.color });
+        });
+
+        return { chips, remainder: this.fromCents(cents) };
+    },
+
+    // "2×$50, 1×$25, 2×$1" — the breakdown as a dealer would say it out loud.
+    //
+    // A table with no chip legend gets nothing rather than "$132 no chip covers": it
+    // hasn't told us its denominations, so there is no advice to give and the amount
+    // stands on its own. A legend that exists but can't reach the amount is different,
+    // and does say so.
+    formatChipBreakdown(amount, legend) {
+        const hasDenominations = (legend || []).some(chip => this.toCents(chip.value) > 0);
+        if (!hasDenominations) return "";
+
+        const { chips, remainder } = this.chipBreakdown(amount, legend);
+        if (chips.length === 0 && remainder === 0) return "";
+        const parts = chips.map(chip => `${chip.count}×${this.format(chip.value)}`);
+        if (remainder > 0) parts.push(`${this.format(remainder)} no chip covers`);
+        return parts.join(", ");
+    },
+
+    // Should focusing this field select what's already in it?
+    //
+    // Every amount box in this tool opens pre-filled with a suggestion: the raise pad
+    // offers the minimum, Add chips offers a buy-in, the seat editor offers the stack
+    // it already has. A dealer taps the box because they want a *different* number,
+    // and a tap puts the caret after the suggestion instead of over it. Measured on a
+    // phone: the raise pad showing 4, tap, type "60" — the field reads 460. Add chips
+    // showing 200, tap, type "50" — 20050.
+    //
+    // Only number boxes. A name or a note is a thing you edit, and selecting all of
+    // it on focus would be the same mistake pointing the other way.
+    selectsOnFocus(field) {
+        if (!field || field.tagName !== "INPUT") return false;
+        const type = String(field.type || "").toLowerCase();
+        if (type === "number") return true;
+        return type === "text" && String(field.inputMode || "").toLowerCase() === "decimal";
+    },
+
+    // "+$40.00" / "-$40.00" rather than "$-40.00" — a standings column is read at a
+    // glance, and the sign belongs out front where the eye lands first.
+    formatSigned(amount) {
+        const value = Number(amount) || 0;
+        if (value > 0) return `+${this.format(value)}`;
+        if (value < 0) return `-${this.format(Math.abs(value))}`;
+        return this.format(0);
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = Money;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/potCalculator.js

@@ -0,0 +1,173 @@
+// Pure side-pot math. No DOM, no globals besides the PotCalculator namespace, so the
+// dealer's payout logic can be reasoned about (and unit tested) on its own.
+//
+// A "contribution entry" is { id, remaining, folded }. `remaining` starts as the amount
+// that player put in the pot and is whittled down round by round as money gets paid out.
+const PotCalculator = {
+    EPSILON: Money.EPSILON,
+
+    // Builds the initial entry list from raw contributions, keeping folded players in
+    // (their chips are still "dead money" owed to whoever wins) while excluding anyone
+    // who put in nothing at all.
+    buildEntries(players) {
+        return players
+            .filter(p => p.contribution > this.EPSILON)
+            .map(p => ({ id: p.id, remaining: p.contribution, folded: !!p.folded }));
+    },
+
+    totalPot(entries) {
+        return entries.reduce((sum, e) => sum + e.remaining, 0);
+    },
+
+    // Players still eligible to be picked as a winner for the money that's left.
+    getContenders(entries) {
+        return entries.filter(e => !e.folded && e.remaining > this.EPSILON);
+    },
+
+    // Splits the money on the table into the main pot and any side pots, with who can
+    // win each. Read-only — this is what a dealer says out loud before the showdown
+    // ("main pot four-eighty, side pot ninety between seats 3 and 5"), which is the
+    // announcement that goes missing far more often than the arithmetic goes wrong.
+    //
+    // Every distinct all-in amount opens a new layer: each player pays into a layer up
+    // to their own contribution, and only players who reached that height can win it.
+    // Folded money stays in — it's dead money owed to whoever wins the layer it fell in.
+    layers(players) {
+        // Uncalled chips were never played for, so they come off the top before any
+        // pot is built. Deriving the pots from what's left is what keeps this function
+        // and uncalledReturns() from disagreeing about the same money — they used to
+        // decide "uncontested" separately, and an overbet that its own bettor was
+        // still live for got announced as a side pot only they could win.
+        const returned = new Map(this.uncalledReturns(players).map(r => [r.id, Money.toCents(r.amount)]));
+        const live = players
+            .map(p => ({ ...p, cents: Money.toCents(p.contribution) - (returned.get(p.id) || 0) }))
+            .filter(p => p.cents > 0);
+        if (live.length === 0) return [];
+
+        const heights = [...new Set(live.map(p => p.cents))].sort((a, b) => a - b);
+
+        const layers = [];
+        let floor = 0;
+        heights.forEach(height => {
+            const band = height - floor;
+            const payers = live.filter(p => p.cents >= height);
+            const amount = band * payers.length;
+            const eligible = payers.filter(p => !p.folded).map(p => p.id);
+
+            if (amount > 0) {
+                if (eligible.length > 0) {
+                    layers.push({ amount: Money.fromCents(amount), eligible });
+                } else if (layers.length > 0) {
+                    // Everyone who reached this height folded, so it isn't a pot of its
+                    // own — it's dead money owed to whoever wins the layer underneath.
+                    // Dropping it would quietly shrink the announced pot.
+                    const below = layers[layers.length - 1];
+                    below.amount = Money.round(below.amount + Money.fromCents(amount));
+                }
+                // With no layer underneath either, nobody in the hand is live at all.
+                // That's a fold flag the dealer needs to fix, not a payout to guess at.
+            }
+            floor = height;
+        });
+
+        // Consecutive layers with the same set of eligible players are one pot to a
+        // dealer — nobody announces two side pots between the same two people.
+        const merged = [];
+        layers.forEach(layer => {
+            const previous = merged[merged.length - 1];
+            const sameEligibility =
+                previous &&
+                previous.eligible.length === layer.eligible.length &&
+                previous.eligible.every(id => layer.eligible.includes(id));
+
+            if (sameEligibility) {
+                previous.amount = Money.round(previous.amount + layer.amount);
+            } else {
+                merged.push({ ...layer });
+            }
+        });
+
+        return merged.map((layer, index) => ({
+            ...layer,
+            label: index === 0 ? "Main pot" : `Side pot ${index}`,
+        }));
+    },
+
+    // Chips nobody could call, which the dealer pushes back rather than into the pot.
+    //
+    // A bet is only called up to what somebody *else* was willing to put in, so the
+    // ceiling for each player is the largest contribution among everyone but them.
+    // Measuring against the whole table instead — including the bettor's own chips —
+    // makes the biggest bet its own yardstick, so the one case this exists for (you
+    // shove, a short stack calls for less) comes back empty.
+    uncalledReturns(players) {
+        const contributing = players.filter(p => p.contribution > this.EPSILON);
+
+        // Nobody live at all means the fold flags are wrong, not that every chip on
+        // the table was uncalled. That's a correction for the dealer to make, so say
+        // nothing here and let the wizard ask them to fix it.
+        if (contributing.filter(p => !p.folded).length === 0) return [];
+
+        const cents = contributing.map(p => Money.toCents(p.contribution));
+
+        return contributing
+            .map((p, index) => {
+                const others = cents.filter((_, i) => i !== index);
+                const cap = others.length > 0 ? Math.max(...others) : 0;
+                return { id: p.id, amount: Money.fromCents(cents[index] - cap) };
+            })
+            .filter(r => r.amount > this.EPSILON);
+    },
+
+    // Awards the current pot layer to `winnerIds` (one id, or several for a split/tie).
+    // The payout is capped at the smallest remaining contribution among the winners —
+    // that's the classic side-pot rule: an all-in player can only win what everyone at
+    // the table matched, and the excess rolls forward to the next round.
+    resolveRound(entries, winnerIds) {
+        const winners = entries.filter(e => winnerIds.includes(e.id) && e.remaining > this.EPSILON);
+        if (winners.length === 0) {
+            throw new Error("No valid winners selected for this round.");
+        }
+
+        const cap = Math.min(...winners.map(w => w.remaining));
+        let payoutPool = 0;
+        const updatedEntries = entries.map(e => {
+            if (e.remaining <= this.EPSILON) return e;
+            const used = Math.min(e.remaining, cap);
+            payoutPool += used;
+            return { ...e, remaining: Money.round(e.remaining - used) };
+        });
+
+        payoutPool = Money.round(payoutPool);
+        const baseShareCents = Math.floor(Money.toCents(payoutPool) / winners.length);
+        let leftoverCents = Money.toCents(payoutPool) - baseShareCents * winners.length;
+
+        const perWinner = winnerIds
+            .filter(id => winners.some(w => w.id === id))
+            .map(id => ({ id, amountCents: baseShareCents }));
+
+        // Odd cents (can't split evenly) go one at a time to the winners, in the order
+        // they were selected, so nothing is ever lost to rounding.
+        let i = 0;
+        while (leftoverCents > 0 && perWinner.length > 0) {
+            perWinner[i % perWinner.length].amountCents += 1;
+            leftoverCents--;
+            i++;
+        }
+
+        const result = perWinner.map(w => ({ id: w.id, amount: Money.fromCents(w.amountCents) }));
+        const remainingContenders = this.getContenders(updatedEntries);
+
+        return {
+            payoutPool,
+            capApplied: cap,
+            perWinner: result,
+            updatedEntries,
+            remainingContenders,
+        };
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = PotCalculator;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/potWizard.js

@@ -0,0 +1,315 @@
+// Walks the dealer through awarding the pot: "who won?", and if that player was
+// all-in for less than everyone else, "who's next?" — repeating until every dollar
+// in the pot has been assigned. Built on PotCalculator's pure round-resolution math.
+const PotWizard = {
+    state: null,
+    onFinished: null,
+    entries: [],
+    playerLabelById: new Map(),
+    log: [],
+
+    open(state, onFinished) {
+        this.state = state;
+        this.onFinished = onFinished;
+
+        const players = state.seats.filter(
+            p => HoldemState.computeContribution(p, state.chipLegend, state.basePotAmount) > 0
+        );
+        this.playerLabelById = new Map(
+            players.map(p => [p.id, this.labelFor(p, state.seats.indexOf(p))])
+        );
+        this.seatIndexById = new Map(players.map(p => [p.id, state.seats.indexOf(p)]));
+        // The label carries name and cards together for the log and the payout lines;
+        // the choice rows want them separately so each can be styled and read on its own.
+        this.nameById = new Map(
+            players.map(p => [p.id, HoldemState.displayName(p, state.seats.indexOf(p))])
+        );
+        this.cardsById = new Map(
+            players.map(p => [p.id, (p.cards || []).filter(Boolean)])
+        );
+        const contributions = players.map(p => ({
+            id: p.id,
+            contribution: HoldemState.computeContribution(p, state.chipLegend, state.basePotAmount),
+            // A seat switched off mid-hand still has its chips in the pot, but it
+            // can no more win them than a folded one can — same dead money, and the
+            // wizard must not offer it as a winner.
+            folded: p.folded || HoldemState.isDeadMoney(p),
+        }));
+        this.entries = PotCalculator.buildEntries(contributions);
+        // Kept so the wizard can show the whole breakdown up front, not just the layer
+        // it happens to be asking about.
+        this.layers = PotCalculator.layers(contributions);
+        this.returns = PotCalculator.uncalledReturns(contributions);
+        this.log = [];
+        this.totals = new Map();
+
+        document.getElementById("potWizardOverlay").hidden = false;
+        this.renderStep();
+    },
+
+    close() {
+        document.getElementById("potWizardOverlay").hidden = true;
+    },
+
+    labelFor(player, seatIndex) {
+        const name = HoldemState.displayName(player, seatIndex);
+        const cards = (player.cards || []).filter(Boolean).map(c => Render.formatCard(c)).join(" ");
+        return cards ? `${name} (${cards})` : name;
+    },
+
+    addToTotal(id, amount) {
+        this.totals.set(id, (this.totals.get(id) || 0) + amount);
+    },
+
+    // A chopped pot rarely divides exactly, and the odd chip goes to the first player
+    // left of the button — not to whoever the dealer happened to tick first. The
+    // calculator hands leftovers out in the order it's given the winners, so ordering
+    // them here is what makes the payout match the rule.
+    orderFromButton(ids) {
+        const distance = new Map();
+        for (let step = 1; step <= this.state.seatCount; step++) {
+            distance.set(HoldemState.nextSeatIndex(this.state, this.state.dealerSeatIndex, step), step);
+        }
+        return [...ids].sort((a, b) =>
+            (distance.get(this.seatIndexById.get(a)) ?? 0) - (distance.get(this.seatIndexById.get(b)) ?? 0)
+        );
+    },
+
+    renderStep() {
+        // Auto-resolve any round where only one player is left standing — nothing to ask.
+        let contenders = PotCalculator.getContenders(this.entries);
+        while (contenders.length === 1) {
+            const result = PotCalculator.resolveRound(this.entries, [contenders[0].id]);
+            this.recordRound(result);
+            this.entries = result.updatedEntries;
+            contenders = PotCalculator.getContenders(this.entries);
+        }
+
+        const body = document.getElementById("potWizardBody");
+        body.innerHTML = "";
+        if (this.log.length === 0) body.appendChild(this.renderBreakdown());
+        body.appendChild(this.renderLog());
+
+        const remaining = PotCalculator.totalPot(this.entries.filter(e => e.remaining > PotCalculator.EPSILON));
+
+        if (contenders.length === 0 && remaining > PotCalculator.EPSILON) {
+            const warning = document.createElement("p");
+            warning.className = "potWizardPrompt";
+
+            // Money left over because nobody could call it isn't a pot anyone won —
+            // it goes back to whoever put it in. Telling the dealer to un-fold someone
+            // to "win" it would be wrong.
+            const returned = (this.returns || []).reduce((sum, r) => sum + r.amount, 0);
+            if (Math.abs(returned - remaining) <= PotCalculator.EPSILON && returned > 0) {
+                const who = this.returns.map(r => this.playerLabelById.get(r.id)).join(", ");
+                warning.textContent = `${Money.format(remaining)} was never called — push it back to ${who} rather than paying it out.`;
+            } else {
+                warning.textContent = `${Money.format(remaining)} is still unassigned, but every remaining player is marked Folded. Uncheck Fold on whoever should win it.`;
+            }
+            body.appendChild(warning);
+            body.appendChild(this.renderSummary());
+            return;
+        }
+
+        if (contenders.length === 0 || remaining <= PotCalculator.EPSILON) {
+            body.appendChild(this.renderSummary());
+            return;
+        }
+
+        const round = document.createElement("div");
+        round.className = "potWizardRound";
+
+        const prompt = document.createElement("p");
+        prompt.className = "potWizardPrompt";
+        prompt.innerHTML = this.log.length === 0
+            ? `Who won the hand? <strong>${Money.format(remaining)}</strong> is in play.`
+            : `That side pot still leaves <strong>${Money.format(remaining)}</strong> unassigned — who's next best?`;
+        round.appendChild(prompt);
+
+        const choices = document.createElement("div");
+        choices.className = "potWizardChoices";
+        contenders.forEach(c => {
+            const label = document.createElement("label");
+            label.className = "potWizardChoice";
+
+            const checkbox = document.createElement("input");
+            checkbox.type = "checkbox";
+            checkbox.value = c.id;
+            // The row is the target, not the box — so the row has to look chosen too.
+            checkbox.addEventListener("change", () => {
+                label.classList.toggle("chosen", checkbox.checked);
+            });
+            label.appendChild(checkbox);
+
+            const text = document.createElement("span");
+            text.className = "potWizardChoiceText";
+
+            const name = document.createElement("span");
+            name.className = "potWizardChoiceName";
+            name.textContent = this.nameById.get(c.id);
+            text.appendChild(name);
+
+            const upTo = document.createElement("span");
+            upTo.className = "potWizardChoiceUpTo";
+            upTo.textContent = `up to ${Money.format(c.remaining)}`;
+            text.appendChild(upTo);
+            label.appendChild(text);
+
+            // Cards sit apart from the name rather than inside it, so a dealer reading
+            // a row across the table sees the hand, not a sentence.
+            const cards = this.cardsById.get(c.id) || [];
+            if (cards.length > 0) {
+                const cardsEl = document.createElement("span");
+                cardsEl.className = "potWizardChoiceCards";
+                cards.forEach((card, i) => {
+                    if (i > 0) cardsEl.appendChild(document.createTextNode(" "));
+                    const span = document.createElement("span");
+                    if (/[HD]$/i.test(card)) span.className = "cardRed";
+                    span.textContent = Render.formatCard(card);
+                    cardsEl.appendChild(span);
+                });
+                label.appendChild(cardsEl);
+            }
+
+            choices.appendChild(label);
+        });
+        round.appendChild(choices);
+
+        const hint = document.createElement("p");
+        hint.className = "fieldHint";
+        hint.textContent = "Check more than one to split the pot on a tie.";
+        round.appendChild(hint);
+
+        const confirmBtn = document.createElement("button");
+        confirmBtn.className = "holdemBtn holdemBtnAccent";
+        confirmBtn.textContent = "Confirm Winner(s)";
+        confirmBtn.addEventListener("click", () => {
+            const selected = Array.from(choices.querySelectorAll("input:checked")).map(i => i.value);
+            if (selected.length === 0) return;
+            const result = PotCalculator.resolveRound(this.entries, this.orderFromButton(selected));
+            this.recordRound(result);
+            this.entries = result.updatedEntries;
+            this.renderStep();
+        });
+        round.appendChild(confirmBtn);
+
+        body.appendChild(round);
+    },
+
+    recordRound(result) {
+        result.perWinner.forEach(w => this.addToTotal(w.id, w.amount));
+        this.log.push({
+            amount: result.payoutPool,
+            winners: result.perWinner.map(w => `${this.playerLabelById.get(w.id)} (${Money.format(w.amount)})`),
+        });
+    },
+
+    // The announcement, spelled out before anyone is asked to pick a winner: what the
+    // main pot is worth, what each side pot is worth, and who can win each.
+    renderBreakdown() {
+        const node = Render.buildPotBreakdown(
+            this.layers || [],
+            this.returns || [],
+            id => this.playerLabelById.get(id),
+            "Announce before the showdown"
+        );
+        if (!node) return document.createDocumentFragment();
+        node.classList.add("potBreakdownWizard");
+        return node;
+    },
+
+    renderLog() {
+        const wrap = document.createElement("div");
+        wrap.className = "potWizardLog";
+        if (this.log.length === 0) return wrap;
+
+        this.log.forEach((entry, idx) => {
+            const line = document.createElement("p");
+            line.className = "potWizardLogLine";
+            line.textContent = `Pot ${idx + 1}: ${Money.format(entry.amount)} → ${entry.winners.join(", ")}`;
+            wrap.appendChild(line);
+        });
+        return wrap;
+    },
+
+    renderSummary() {
+        const wrap = document.createElement("div");
+        wrap.className = "potWizardSummary";
+
+        const heading = document.createElement("h3");
+        heading.textContent = "Final Payouts";
+        wrap.appendChild(heading);
+
+        if (this.totals.size === 0) {
+            const empty = document.createElement("p");
+            empty.className = "fieldHint";
+            empty.textContent = "Nobody has money in this pot yet — mark seats \"In hand\" and set contributions first.";
+            wrap.appendChild(empty);
+        } else {
+            const legend = (this.state && this.state.chipLegend) || [];
+            const list = document.createElement("ul");
+            for (const [id, amount] of this.totals.entries()) {
+                const li = document.createElement("li");
+                li.textContent = `${this.playerLabelById.get(id)} — ${Money.format(amount)}`;
+
+                // The amount is the answer to the arithmetic; the chips are the answer
+                // to the dealer's job. Only when the legend has been filled in — a
+                // table that never set up chip colours gets the number on its own,
+                // which is what it had before.
+                const chips = Money.formatChipBreakdown(amount, legend);
+                if (chips) {
+                    const note = document.createElement("span");
+                    note.className = "payoutChips";
+                    note.textContent = chips;
+                    li.appendChild(note);
+                }
+                list.appendChild(li);
+            }
+            wrap.appendChild(list);
+        }
+
+        const actions = document.createElement("div");
+        actions.className = "potWizardActions";
+
+        const applyBtn = document.createElement("button");
+        applyBtn.className = "holdemBtn holdemBtnAccent";
+        applyBtn.textContent = "Start Next Hand";
+        applyBtn.addEventListener("click", () => {
+            const payouts = Array.from(this.totals.entries()).map(([id, amount]) => ({
+                id,
+                label: this.playerLabelById.get(id),
+                amount,
+            }));
+            this.close();
+            this.onFinished(payouts);
+        });
+        actions.appendChild(applyBtn);
+
+        // This button cancels — it does not pay anybody. Under a heading reading
+        // "Final Payouts" with an amount beside a name, "Close" reads like dismissing
+        // something already done, and a dealer who taps it walks away believing the
+        // pot has been pushed. It hasn't: the chips are still in the middle and the
+        // hand isn't logged. So it says what it does.
+        const cancelBtn = document.createElement("button");
+        cancelBtn.className = "holdemBtn holdemBtnGhost";
+        cancelBtn.textContent = "Cancel — don't pay yet";
+        cancelBtn.addEventListener("click", () => this.close());
+        actions.appendChild(cancelBtn);
+
+        if (this.totals.size > 0) {
+            const note = document.createElement("p");
+            note.className = "fieldHint potWizardPendingNote";
+            note.textContent = "Nothing has been paid out yet. Start Next Hand pushes the pot and logs the hand.";
+            wrap.appendChild(actions);
+            wrap.appendChild(note);
+            return wrap;
+        }
+
+        wrap.appendChild(actions);
+        return wrap;
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = PotWizard;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/quickSplit.js

@@ -0,0 +1,287 @@
+// The quick-split screen: pot in, payout out, nothing to set up and nothing saved.
+// A dealer opens this one-handed with players waiting, so every control is a tap and
+// the answer updates as they type rather than behind a "calculate" button.
+const QuickSplit = {
+    WAY_CHOICES: [2, 3, 4, 5],
+    CHIP_CHOICES: [
+        { value: 0.01, label: "1¢" },
+        { value: 0.25, label: "25¢" },
+        { value: 1, label: "$1" },
+        { value: 5, label: "$5" },
+        { value: 25, label: "$25" },
+    ],
+    MAX_WAYS: 12,
+
+    ways: 2,
+    chip: 1,
+
+    // "even" is the common case — one pot, everyone matched. "uneven" is the one this
+    // screen used to send people back to the full table for: somebody all-in for less,
+    // so the money splits into a main pot and side pots.
+    mode: "even",
+    entries: [],
+
+    mount() {
+        this.potInput = document.getElementById("potInput");
+        this.clearPotBtn = document.getElementById("clearPotBtn");
+        this.entries = [{ amount: "", folded: false }, { amount: "", folded: false }, { amount: "", folded: false }];
+
+        this.renderWayChoices();
+        this.renderChipChoices();
+        this.renderUnevenRows();
+
+        document.getElementById("modeEvenBtn").addEventListener("click", () => this.setMode("even"));
+        document.getElementById("modeUnevenBtn").addEventListener("click", () => this.setMode("uneven"));
+        document.getElementById("addPlayerBtn").addEventListener("click", () => {
+            this.entries.push({ amount: "", folded: false });
+            this.renderUnevenRows();
+            this.update();
+        });
+
+        this.potInput.addEventListener("input", () => {
+            this.sanitizePotInput();
+            this.update();
+        });
+
+        this.clearPotBtn.addEventListener("click", () => {
+            this.potInput.value = "";
+            this.potInput.focus();
+            this.update();
+        });
+
+        document.getElementById("resetSplitBtn").addEventListener("click", () => {
+            this.potInput.value = "";
+            this.ways = 2;
+            this.chip = 1;
+            this.renderWayChoices();
+            this.renderChipChoices();
+            this.potInput.focus();
+            this.update();
+        });
+
+        this.update();
+    },
+
+    // Keeps the field to something parseable without fighting the typist: digits and a
+    // single decimal point, at most two places.
+    sanitizePotInput() {
+        const cleaned = this.potInput.value
+            .replace(/[^0-9.]/g, "")
+            .replace(/(\..*)\./g, "$1")
+            .replace(/(\.\d\d)\d+/, "$1");
+        if (cleaned !== this.potInput.value) this.potInput.value = cleaned;
+    },
+
+    makeChoiceButton(label, isSelected, onPick) {
+        const btn = document.createElement("button");
+        btn.type = "button";
+        btn.className = "choiceChip";
+        btn.textContent = label;
+        btn.setAttribute("aria-pressed", String(isSelected));
+        btn.classList.toggle("selected", isSelected);
+        btn.addEventListener("click", onPick);
+        return btn;
+    },
+
+    renderWayChoices() {
+        const row = document.getElementById("waysChoices");
+        row.innerHTML = "";
+
+        this.WAY_CHOICES.forEach(count => {
+            row.appendChild(
+                this.makeChoiceButton(String(count), this.ways === count, () => {
+                    this.ways = count;
+                    this.renderWayChoices();
+                    this.update();
+                })
+            );
+        });
+
+        // Beyond a five-way chop it's rare enough to hide behind a stepper rather than
+        // spend a row of buttons on it.
+        const more = document.createElement("div");
+        more.className = "waysStepper";
+
+        const minus = this.makeStepButton("−", () => this.stepWays(-1));
+        const plus = this.makeStepButton("+", () => this.stepWays(1));
+        const readout = document.createElement("span");
+        readout.className = "waysReadout";
+        readout.textContent = `${this.ways} ways`;
+
+        more.appendChild(minus);
+        more.appendChild(readout);
+        more.appendChild(plus);
+        row.appendChild(more);
+    },
+
+    makeStepButton(label, onPick) {
+        const btn = document.createElement("button");
+        btn.type = "button";
+        btn.className = "stepBtn";
+        btn.textContent = label;
+        btn.addEventListener("click", onPick);
+        return btn;
+    },
+
+    stepWays(delta) {
+        this.ways = Math.max(2, Math.min(this.MAX_WAYS, this.ways + delta));
+        this.renderWayChoices();
+        this.update();
+    },
+
+    renderChipChoices() {
+        const row = document.getElementById("chipChoices");
+        row.innerHTML = "";
+        this.CHIP_CHOICES.forEach(choice => {
+            row.appendChild(
+                this.makeChoiceButton(choice.label, this.chip === choice.value, () => {
+                    this.chip = choice.value;
+                    this.renderChipChoices();
+                    this.update();
+                })
+            );
+        });
+    },
+
+    setMode(mode) {
+        this.mode = mode;
+        document.getElementById("modeEvenBtn").classList.toggle("selected", mode === "even");
+        document.getElementById("modeUnevenBtn").classList.toggle("selected", mode === "uneven");
+
+        document.querySelectorAll(".evenOnly").forEach(el => { el.hidden = mode !== "even"; });
+        document.querySelectorAll(".unevenOnly").forEach(el => { el.hidden = mode !== "uneven"; });
+        document.getElementById("splitResult").hidden = mode !== "even";
+        document.getElementById("unevenResult").hidden = mode !== "uneven";
+
+        this.update();
+    },
+
+    renderUnevenRows() {
+        const host = document.getElementById("unevenRows");
+        const template = document.getElementById("unevenRowTemplate");
+        host.innerHTML = "";
+
+        this.entries.forEach((entry, index) => {
+            const row = template.content.firstElementChild.cloneNode(true);
+            row.querySelector(".unevenRowLabel").textContent = `P${index + 1}`;
+
+            const amount = row.querySelector(".unevenAmount");
+            amount.value = entry.amount;
+            amount.setAttribute("aria-label", `Player ${index + 1} amount`);
+            amount.addEventListener("input", () => {
+                entry.amount = amount.value.replace(/[^0-9.]/g, "").replace(/(\..*)\./g, "$1");
+                if (entry.amount !== amount.value) amount.value = entry.amount;
+                this.update();
+            });
+
+            // Folded money stays in the pot as dead money, but its owner can't win any
+            // of it — which is exactly the distinction that makes side pots tricky.
+            const fold = row.querySelector(".unevenFoldBtn");
+            fold.classList.toggle("selected", entry.folded);
+            fold.setAttribute("aria-pressed", String(entry.folded));
+            fold.addEventListener("click", () => {
+                entry.folded = !entry.folded;
+                this.renderUnevenRows();
+                this.update();
+            });
+
+            const remove = row.querySelector(".unevenRemoveBtn");
+            remove.disabled = this.entries.length <= 2;
+            remove.addEventListener("click", () => {
+                this.entries.splice(index, 1);
+                this.renderUnevenRows();
+                this.update();
+            });
+
+            host.appendChild(row);
+        });
+    },
+
+    updateUneven() {
+        const players = this.entries
+            .map((entry, index) => ({ id: `P${index + 1}`, contribution: Number(entry.amount) || 0, folded: entry.folded }))
+            .filter(p => p.contribution > 0);
+
+        const pots = PotCalculator.layers(players);
+        const returns = PotCalculator.uncalledReturns(players);
+
+        const host = document.getElementById("unevenPots");
+        const empty = document.getElementById("unevenEmpty");
+        host.innerHTML = "";
+
+        if (pots.length === 0 && returns.length === 0) {
+            empty.hidden = false;
+            empty.textContent = players.length === 0
+                ? "Enter what each player put in."
+                : "Nobody left who can win — un-fold whoever should take it.";
+            return;
+        }
+        empty.hidden = true;
+
+        const addRow = (label, amount, who, className) => {
+            const row = document.createElement("div");
+            row.className = `unevenPot ${className || ""}`;
+            const name = document.createElement("span");
+            name.className = "unevenPotLabel";
+            name.textContent = label;
+            const value = document.createElement("span");
+            value.className = "unevenPotAmount";
+            value.textContent = Money.format(amount);
+            const eligible = document.createElement("span");
+            eligible.className = "unevenPotWho";
+            eligible.textContent = who;
+            row.appendChild(name);
+            row.appendChild(value);
+            row.appendChild(eligible);
+            host.appendChild(row);
+        };
+
+        pots.forEach(pot => addRow(pot.label, pot.amount, pot.eligible.join(", ")));
+        returns.forEach(ret => addRow("Uncalled", ret.amount, `back to ${ret.id}`, "unevenPotReturn"));
+
+        const total = players.reduce((sum, p) => sum + p.contribution, 0);
+        addRow("On the table", Money.round(total), "", "unevenPotTotal");
+    },
+
+    update() {
+        if (this.mode === "uneven") {
+            this.updateUneven();
+            return;
+        }
+
+        const potValue = Number(this.potInput.value);
+        const pot = Number.isNaN(potValue) ? 0 : potValue;
+        this.clearPotBtn.hidden = this.potInput.value === "";
+
+        const result = SplitCalculator.split(pot, this.ways, this.chip);
+
+        document.getElementById("splitResultLabel").textContent =
+            `Each of ${result.players} players gets`;
+        document.getElementById("splitResultAmount").textContent = Money.format(result.each);
+
+        const oddNote = document.getElementById("splitOddNote");
+        if (result.valid && result.oddChips > 0) {
+            oddNote.textContent = result.oddChips === 1
+                ? `plus one odd ${Money.format(result.chip)} chip to the first player left of the button`
+                : `plus ${result.oddChips} odd ${Money.format(result.chip)} chips — one each to the ` +
+                  `first ${result.oddChips} players left of the button`;
+            oddNote.hidden = false;
+        } else {
+            oddNote.hidden = true;
+        }
+
+        const dustNote = document.getElementById("splitDustNote");
+        if (result.valid && result.dust > 0) {
+            dustNote.textContent =
+                `${Money.format(result.dust)} doesn't divide into ${Money.format(result.chip)} chips — ` +
+                `pick a smaller denomination.`;
+            dustNote.hidden = false;
+        } else {
+            dustNote.hidden = true;
+        }
+
+        document.getElementById("splitResult").classList.toggle("hasAmount", result.valid && result.each > 0);
+    },
+};
+
+document.addEventListener("DOMContentLoaded", () => QuickSplit.mount());

JoshHeaps.Net/wwwroot/js/casino/holdem/render.js

@@ -0,0 +1,907 @@
+// All DOM rendering + drag/drop for the table. Talks to the outside world only through
+// the `hooks` object passed to mount(): hooks.save(state) persists, hooks.rerender()
+// re-draws everything (used after structural changes like resizing seats or the chip
+// legend).
+//
+// The table itself only shows compact seat "pucks" — name, cards, total, blind/dealer
+// badges — because a full data-entry form (chip counts, custom fields, etc.) doesn't fit
+// next to nine others arranged in a circle at any screen size. Clicking a puck opens the
+// full form in the seat editor panel instead.
+const Render = {
+    state: null,
+    hooks: null,
+    selectedSeatIndex: null,
+
+    mount(state, hooks) {
+        this.state = state;
+        this.hooks = hooks;
+        this.selectedSeatIndex = null;
+        // A reset hands over a different table entirely, so nothing cached about the
+        // last one still applies.
+        this.lastHistorySignature = null;
+        this.handTimeCache.clear();
+        this.renderAll();
+    },
+
+    renderAll() {
+        if (this.selectedSeatIndex !== null && this.selectedSeatIndex >= this.state.seatCount) {
+            this.selectedSeatIndex = null;
+        }
+        this.renderSeats();
+        this.renderSeatEditor();
+        this.renderChipLegend();
+        this.renderNotes();
+        this.updatePotBadge();
+        this.renderSetupFields();
+        this.renderTableHint();
+        this.renderStandings();
+        this.renderHandHistory();
+        if (typeof ActionBar !== "undefined" && ActionBar.state) ActionBar.render();
+    },
+
+    renderSetupFields() {
+        document.getElementById("seatCountInput").value = this.state.seatCount;
+        document.getElementById("directionSelect").value = this.state.direction;
+        document.getElementById("basePotInput").value = this.state.basePotAmount ?? "";
+        document.getElementById("dedicatedDealerToggle").checked = !!this.state.dedicatedDealer;
+        document.getElementById("smallBlindInput").value = this.state.smallBlind ?? "";
+        document.getElementById("bigBlindInput").value = this.state.bigBlind ?? "";
+        document.getElementById("defaultStackInput").value = this.state.defaultStack ?? "";
+    },
+
+    // Whether this device can actually drag a seat. HTML5 drag events are never
+    // generated from a touch screen, so on a phone the last clause of the hint below
+    // described something impossible — on the device the rest of the sentence was
+    // written for. Touch gets told about the menu route instead, which works.
+    canDragSeats() {
+        return typeof matchMedia !== "function" || matchMedia("(hover: hover)").matches;
+    },
+
+    renderTableHint() {
+        const hint = document.getElementById("tableHint");
+        // Gestures are invisible until someone tells you about them, and this is the
+        // only place on the table with room to say so.
+        hint.textContent = this.canDragSeats()
+            ? "Tap a seat to edit · double-tap to fold · press and hold for quick actions · drag to swap seats."
+            : "Tap a seat to edit · double-tap to fold · press and hold for quick actions, including moving a seat.";
+    },
+
+    renderNotes() {
+        const notesEl = document.getElementById("tableNotes");
+        if (document.activeElement !== notesEl) notesEl.value = this.state.notes || "";
+    },
+
+    updatePotBadge() {
+        // Chips still sitting in front of players on the current street are part of
+        // the pot as far as anyone at the table is concerned, so count them — waiting
+        // until the street closes would show a stale number for most of every hand.
+        const swept = HoldemState.totalPot(this.state);
+        const onStreet = this.state.seats.reduce((sum, p) => sum + Betting.committed(p), 0);
+        document.getElementById("potBadgeAmount").textContent = Money.format(swept + onStreet);
+    },
+
+    // ---- Seats around the table (compact pucks) ----
+
+    seatPosition(index, count) {
+        return this.positionOnRing(index, count, 44, 42);
+    },
+
+    // Bets sit on the felt between their player and the pot, the way chips actually
+    // do — closer in than the seats, on the same spoke. The bets layer is inset to
+    // match the seat ring (see the CSS), so this one radius holds at every size.
+    betPosition(index, count) {
+        return this.positionOnRing(index, count, 27, 25);
+    },
+
+    positionOnRing(index, count, rx, ry) {
+        const angle = -90 + (360 / count) * index;
+        const radians = (angle * Math.PI) / 180;
+        return {
+            left: 50 + rx * Math.cos(radians),
+            top: 50 + ry * Math.sin(radians),
+        };
+    },
+
+    // Colour a bet by the biggest chip that fits it, so a table with a chip legend
+    // gets bets that look like the chips actually being pushed out.
+    chipColorFor(amount) {
+        const legend = [...(this.state.chipLegend || [])]
+            .filter(chip => Number(chip.value) > 0)
+            .sort((a, b) => Number(b.value) - Number(a.value));
+        const match = legend.find(chip => amount >= Number(chip.value));
+        return (match || legend[legend.length - 1] || {}).color || "#8a8a8a";
+    },
+
+    // ---- Bets on the felt ----
+
+    makeBetChip(bet) {
+        const chip = document.createElement("div");
+        chip.className = "betChip";
+
+        const disc = document.createElement("span");
+        disc.className = "betChipDisc";
+        disc.style.background = this.chipColorFor(bet);
+
+        const amount = document.createElement("span");
+        amount.className = "betChipAmount";
+        amount.textContent = Money.format(bet);
+
+        chip.appendChild(disc);
+        chip.appendChild(amount);
+        return chip;
+    },
+
+    // A phone's felt has no room for a third ring: measured every radius between the
+    // seats and the pot badge and each one collides with one or the other. So on a
+    // narrow screen the bet clings to its own puck instead — same chip, no ring —
+    // sitting on whichever side faces the middle of the table.
+    renderBets() {
+        const layer = document.getElementById("betsLayer");
+        if (!layer) return;
+        layer.innerHTML = "";
+
+        const anchorToSeat = window.matchMedia("(max-width: 700px)").matches;
+
+        this.state.seats.forEach((player, index) => {
+            const bet = Betting.committed(player);
+            if (bet <= 0) return;
+
+            const chip = this.makeBetChip(bet);
+            const pos = this.betPosition(index, this.state.seatCount);
+
+            if (anchorToSeat) {
+                const seat = document.querySelector(`.seat[data-seat-index="${index}"]`);
+                if (!seat) return;
+                const seatPos = this.seatPosition(index, this.state.seatCount);
+                chip.classList.add("betChipAnchored", seatPos.top > 50 ? "betChipAbove" : "betChipBelow");
+                seat.appendChild(chip);
+                return;
+            }
+
+            chip.style.left = `${pos.left}%`;
+            chip.style.top = `${pos.top}%`;
+            layer.appendChild(chip);
+        });
+    },
+
+    puckLabel(player, seatIndex) {
+        return HoldemState.displayName(player, seatIndex);
+    },
+
+    renderSeats() {
+        const layer = document.getElementById("seatsLayer");
+        layer.innerHTML = "";
+        const template = document.getElementById("seatTemplate");
+        const { dealerIndex, sbIndex, bbIndex, manual: manualBlinds } = HoldemState.getBlindSeats(this.state);
+
+        this.state.seats.forEach((player, index) => {
+            const node = template.content.firstElementChild.cloneNode(true);
+            const pos = this.seatPosition(index, this.state.seatCount);
+            node.style.left = `${pos.left}%`;
+            node.style.top = `${pos.top}%`;
+            node.dataset.seatIndex = String(index);
+
+            // Which side of the seat the pot is on, which is the side its bet chip
+            // arrives from — the chip sits on the same spoke, closer in. For a seat on
+            // the top of the ring that's from below; on the bottom, from above.
+            //
+            // The blind badge has to be on the other side or the chip lands on top of
+            // it. Measured on a 390px phone: the big blind's own $2 chip covered 196 of
+            // the badge's 288 square pixels, and it sits a layer higher, so the marker
+            // telling the dealer who the big blind is was simply gone.
+            node.classList.toggle("seatBelowCentre", pos.top > 50);
+
+            node.querySelector(".seatChairNumber").textContent = index + 1;
+
+            const dealerChip = node.querySelector(".dealerChip");
+            const hasButton = index === dealerIndex;
+            dealerChip.classList.toggle("active", hasButton);
+            dealerChip.classList.toggle("hidden", !!this.state.dedicatedDealer);
+            // Every one of these announced itself as "D", so a screen reader heard a row
+            // of nine identical buttons and couldn't tell which seat held the real one.
+            // The label now says whose it is, or what pressing it would do.
+            const who = (player.name || "").trim() || `seat ${index + 1}`;
+            const chipLabel = hasButton
+                ? `${who} has the dealer button`
+                : `Give the dealer button to ${who}`;
+            dealerChip.setAttribute("aria-label", chipLabel);
+            dealerChip.title = chipLabel;
+            // Tapping the puck is the same act as "Give the button" in the seat menu,
+            // so it goes through the same hook — otherwise this one path would move
+            // the button without moving the blinds that follow it.
+            dealerChip.addEventListener("click", e => {
+                e.stopPropagation();
+                this.hooks.onGiveButton(index);
+            });
+
+            const sbBadge = node.querySelector(".sbBadge");
+            const bbBadge = node.querySelector(".bbBadge");
+            sbBadge.classList.toggle("visible", index === sbIndex);
+            bbBadge.classList.toggle("visible", index === bbIndex);
+            // A blind the dealer named by hand isn't where the button would have put
+            // it, so it's marked — otherwise the table looks like it's just wrong.
+            // The `!!` matters: getBlindSeats leaves `manual` undefined when the
+            // blinds are positional, and classList.toggle with an undefined second
+            // argument *flips* the class instead of clearing it, so the marker
+            // appeared and disappeared on alternate renders.
+            sbBadge.classList.toggle("blindManual", !!manualBlinds && index === sbIndex);
+            bbBadge.classList.toggle("blindManual", !!manualBlinds && index === bbIndex);
+
+            this.updatePuckContent(node, player, index);
+            node.classList.toggle("seatSelected", index === this.selectedSeatIndex);
+
+            this.wireSeatGestures(node, index);
+            this.wireDragAndDrop(node, index);
+
+            layer.appendChild(node);
+        });
+
+        this.renderBets();
+    },
+
+    isRedSuit(card) {
+        return /[HD]$/i.test(card || "");
+    },
+
+    SUIT_SYMBOLS: { S: "♠", H: "♥", D: "♦", C: "♣" },
+
+    // "KD" -> "K♦". Stored cards stay two plain characters so every existing reader
+    // keeps working; the suit only becomes a symbol on its way to a human.
+    formatCard(card) {
+        const value = (card || "").toUpperCase();
+        if (!value) return "";
+        return `${value[0]}${this.SUIT_SYMBOLS[value[1]] || value[1] || ""}`;
+    },
+
+    // An empty slot has to look like something you can tap, so it gets a placeholder
+    // rather than going blank.
+    paintCardSlot(slot, card) {
+        const value = (card || "").toUpperCase();
+        slot.classList.toggle("cardRed", this.isRedSuit(value));
+        slot.classList.toggle("cardSlotEmpty", !value);
+        slot.textContent = value ? this.formatCard(value) : "＋";
+    },
+
+    // A chair nobody has claimed: no name typed, not dealt in, nothing in the pot.
+    // Worth calling out, because at a short-handed table the open seats are what
+    // the dealer is looking for.
+    isEmptySeat(player) {
+        const named = !!(player.name && player.name.trim());
+        const contributing =
+            HoldemState.computeContribution(player, this.state.chipLegend, this.state.basePotAmount) > 0;
+        return !named && !player.inHand && !contributing;
+    },
+
+    updatePuckContent(node, player, index) {
+        const empty = this.isEmptySeat(player);
+        const nameEl = node.querySelector(".seatPuckName");
+        nameEl.textContent = empty ? "Empty" : (player.name || "").trim();
+        nameEl.classList.toggle("seatEmptyLabel", empty);
+
+        const cardsEl = node.querySelector(".seatPuckCards");
+        cardsEl.innerHTML = "";
+        (player.cards || []).filter(Boolean).forEach((card, i) => {
+            if (i > 0) cardsEl.appendChild(document.createTextNode(" "));
+            const span = document.createElement("span");
+            if (this.isRedSuit(card)) span.className = "cardRed";
+            span.textContent = this.formatCard(card);
+            cardsEl.appendChild(span);
+        });
+        // Always this player's total for the hand. What they've just pushed out on this
+        // street is shown as a chip on the felt instead — the puck used to flip between
+        // the two meanings depending on the moment, which is a bad thing for a number
+        // sitting next to a stack size to do.
+        const handTotal = Betting.handTotal(player);
+        const total = handTotal > 0
+            ? handTotal
+            : HoldemState.computeContribution(player, this.state.chipLegend, this.state.basePotAmount);
+        const totalEl = node.querySelector(".seatPuckTotal");
+        totalEl.textContent = total > 0 ? Money.format(total) : "";
+        this.fitAmount(totalEl);
+
+        // A player with nothing behind used to leave this line blank, so the felt drew
+        // an all-in exactly like a seat whose stack nobody had entered. On a table with
+        // side pots that's the one distinction the dealer is working from — who can
+        // still be bet at, and who is already committed for everything they have.
+        const stackEl = node.querySelector(".seatPuckStack");
+        const stack = Betting.stackOf(this.state, player);
+        const allIn = Betting.isAllIn(this.state, player);
+        stackEl.textContent = empty ? "" : allIn ? "ALL IN" : stack > 0 ? Money.format(stack) : "";
+        stackEl.classList.toggle("seatPuckAllIn", allIn);
+        this.fitAmount(stackEl);
+
+        node.classList.toggle("seatAllIn", allIn);
+        node.classList.toggle("seatActing", index === this.state.actingSeatIndex);
+        node.classList.toggle("seatEmpty", empty);
+        node.classList.toggle("seatInactive", !player.inHand && !empty);
+        node.classList.toggle("seatFolded", player.folded);
+        node.classList.toggle("seatLive", player.inHand && !player.folded);
+    },
+
+    // A seat puck is 64px of usable width. A tournament stack doesn't fit in that and,
+    // because the number has no spaces to break on, it doesn't wrap or ellipsise
+    // either — it just draws straight out over the neighbouring seat. Stepping the
+    // font down keeps every digit, which matters: a dealer misreading a stack is a
+    // worse outcome than a small one, so this shrinks rather than abbreviating.
+    fitAmount(el) {
+        const length = (el.textContent || "").length;
+        el.classList.toggle("puckAmountLong", length >= 8 && length < 10);
+        el.classList.toggle("puckAmountHuge", length >= 10);
+    },
+
+    // Cheaper than a full renderSeats() — used after edits so the seat editor's inputs
+    // (which live in a separate panel) never lose focus.
+    refreshPuck(index) {
+        const node = document.querySelector(`.seat[data-seat-index="${index}"]`);
+        if (node) this.updatePuckContent(node, this.state.seats[index], index);
+    },
+
+    // ---- Seat gestures ----
+    //
+    // One puck, three intents: tap to edit, double-tap to fold, press and hold for
+    // the quick menu. The single tap waits out the double-tap window before it
+    // fires — a fifth of a second of latency on opening a form, in exchange for a
+    // fold that doesn't also fling a sheet up over the table.
+
+    LONG_PRESS_MS: 500,
+    DOUBLE_TAP_MS: 220,
+    DRAG_SLOP_PX: 8,
+    pendingTap: null,
+
+    wireSeatGestures(node, index) {
+        let longPressTimer = null;
+        let longPressFired = false;
+        let startX = 0;
+        let startY = 0;
+
+        const cancelLongPress = () => {
+            if (longPressTimer) {
+                clearTimeout(longPressTimer);
+                longPressTimer = null;
+            }
+        };
+
+        node.addEventListener("pointerdown", e => {
+            longPressFired = false;
+            startX = e.clientX;
+            startY = e.clientY;
+            cancelLongPress();
+            longPressTimer = setTimeout(() => {
+                longPressTimer = null;
+                longPressFired = true;
+                this.cancelPendingTap();
+                node.classList.remove("seatPressing");
+                this.hooks.onSeatLongPress(index);
+            }, this.LONG_PRESS_MS);
+            node.classList.add("seatPressing");
+        });
+
+        // Moving means they're dragging the seat, not holding it.
+        node.addEventListener("pointermove", e => {
+            if (Math.abs(e.clientX - startX) > this.DRAG_SLOP_PX || Math.abs(e.clientY - startY) > this.DRAG_SLOP_PX) {
+                cancelLongPress();
+                node.classList.remove("seatPressing");
+            }
+        });
+
+        ["pointerup", "pointercancel", "pointerleave"].forEach(type => {
+            node.addEventListener(type, () => {
+                cancelLongPress();
+                node.classList.remove("seatPressing");
+            });
+        });
+        node.addEventListener("dragstart", () => {
+            cancelLongPress();
+            this.cancelPendingTap();
+            node.classList.remove("seatPressing");
+        });
+
+        node.addEventListener("click", e => {
+            // The long press already did something; don't also treat the release as a tap.
+            if (longPressFired) {
+                longPressFired = false;
+                e.preventDefault();
+                e.stopPropagation();
+                return;
+            }
+            this.handleSeatTap(index);
+        });
+    },
+
+    cancelPendingTap() {
+        if (this.pendingTap) {
+            clearTimeout(this.pendingTap.timer);
+            this.pendingTap = null;
+        }
+    },
+
+    handleSeatTap(index) {
+        if (this.pendingTap && this.pendingTap.index === index) {
+            this.cancelPendingTap();
+            this.hooks.onSeatDoubleTap(index);
+            return;
+        }
+
+        this.cancelPendingTap();
+        const timer = setTimeout(() => {
+            this.pendingTap = null;
+            this.toggleSeatEditor(index);
+        }, this.DOUBLE_TAP_MS);
+        this.pendingTap = { index, timer };
+    },
+
+    // Tapping the open seat again closes it — on a phone the editor is a sheet over
+    // the table, and the seat you just tapped is the closest thing to hand for
+    // dismissing it.
+    toggleSeatEditor(index) {
+        this.selectedSeatIndex = this.selectedSeatIndex === index ? null : index;
+        this.renderSeats();
+        this.renderSeatEditor();
+    },
+
+    wireDragAndDrop(node, index) {
+        node.addEventListener("dragstart", e => {
+            e.dataTransfer.setData("text/plain", String(index));
+            e.dataTransfer.effectAllowed = "move";
+            node.classList.add("dragging");
+        });
+        node.addEventListener("dragend", () => node.classList.remove("dragging"));
+        node.addEventListener("dragover", e => {
+            e.preventDefault();
+            node.classList.add("dropTarget");
+        });
+        node.addEventListener("dragleave", () => node.classList.remove("dropTarget"));
+        node.addEventListener("drop", e => {
+            e.preventDefault();
+            node.classList.remove("dropTarget");
+            const sourceIndex = Number(e.dataTransfer.getData("text/plain"));
+            const targetIndex = index;
+            if (Number.isNaN(sourceIndex) || sourceIndex === targetIndex) return;
+            const seats = this.state.seats;
+            [seats[sourceIndex], seats[targetIndex]] = [seats[targetIndex], seats[sourceIndex]];
+            this.hooks.save(this.state);
+            this.renderSeats();
+            if (this.selectedSeatIndex === sourceIndex || this.selectedSeatIndex === targetIndex) {
+                this.renderSeatEditor();
+            }
+        });
+    },
+
+    // ---- Seat editor panel (the full form for whichever seat is selected) ----
+
+    closeSeatEditor() {
+        this.selectedSeatIndex = null;
+        this.renderSeats();
+        this.renderSeatEditor();
+    },
+
+    renderSeatEditor() {
+        const title = document.getElementById("seatEditorTitle");
+        const body = document.getElementById("seatEditorBody");
+
+        // Drives the mobile bottom sheet: the panel only slides up over the table
+        // while a seat is actually being edited.
+        document.body.classList.toggle("seatSheetOpen", this.selectedSeatIndex !== null);
+
+        if (this.selectedSeatIndex === null) {
+            title.textContent = "Select a seat";
+            body.innerHTML = '<p class="fieldHint">Click a seat at the table to edit their name, cards, chips and anything else.</p>';
+            return;
+        }
+
+        const index = this.selectedSeatIndex;
+        const player = this.state.seats[index];
+        title.textContent = this.puckLabel(player, index);
+
+        body.innerHTML = "";
+        const template = document.getElementById("seatEditorTemplate");
+        const form = template.content.firstElementChild.cloneNode(true);
+
+        this.wireSeatFields(form, player, index);
+        this.renderChipCounts(form, player, index);
+        this.renderCustomFields(form, player, index);
+        this.renderSeatTotal(form, player);
+
+        body.appendChild(form);
+    },
+
+    renderSeatTotal(form, player) {
+        const total = HoldemState.computeContribution(player, this.state.chipLegend, this.state.basePotAmount);
+        form.querySelector(".seatTotalAmount").textContent = Money.format(total);
+    },
+
+    commitSeatChange(form, player, index) {
+        this.hooks.save(this.state);
+        this.updatePotBadge();
+        this.renderSeatTotal(form, player);
+        this.refreshPuck(index);
+    },
+
+    wireSeatFields(form, player, index) {
+        const nameInput = form.querySelector(".seatNameInput");
+        nameInput.value = player.name;
+        nameInput.addEventListener("input", () => {
+            player.name = nameInput.value;
+            document.getElementById("seatEditorTitle").textContent = this.puckLabel(player, index);
+            this.commitSeatChange(form, player, index);
+        });
+
+        const inHandCheckbox = form.querySelector(".inHandCheckbox");
+        inHandCheckbox.checked = player.inHand;
+        inHandCheckbox.addEventListener("change", () => {
+            player.inHand = inHandCheckbox.checked;
+            if (!player.inHand) player.folded = false;
+            foldCheckboxRef.checked = player.folded;
+            foldCheckboxRef.disabled = !player.inHand;
+            this.commitSeatChange(form, player, index);
+        });
+
+        const foldCheckboxRef = form.querySelector(".foldCheckbox");
+        foldCheckboxRef.checked = player.folded;
+        foldCheckboxRef.disabled = !player.inHand;
+        foldCheckboxRef.addEventListener("change", () => {
+            player.folded = foldCheckboxRef.checked;
+            this.commitSeatChange(form, player, index);
+        });
+
+        const slots = [form.querySelector(".card1Slot"), form.querySelector(".card2Slot")];
+        slots.forEach((slot, cardIdx) => {
+            this.paintCardSlot(slot, player.cards[cardIdx]);
+            slot.addEventListener("click", () => {
+                CardPicker.open(this.state, {
+                    onPick: (seatIndex, pickedIdx, card) => {
+                        this.paintCardSlot(slots[pickedIdx], card);
+                        this.commitSeatChange(form, player, seatIndex);
+                    },
+                }, index, cardIdx);
+            });
+        });
+
+        // What they've handed over tonight, shown next to what's in front of them so a
+        // cash-out is one subtraction rather than a memory test.
+        const boughtIn = Number(player.buyIns) || 0;
+        const boughtInEl = form.querySelector(".seatBuyIns");
+        boughtInEl.textContent = boughtIn > 0 ? `Bought in ${Money.format(boughtIn)}` : "";
+        boughtInEl.hidden = boughtIn <= 0;
+
+        const stackInput = form.querySelector(".stackInput");
+        stackInput.value = player.stack ?? "";
+        stackInput.addEventListener("input", () => {
+            player.stack = stackInput.value === "" ? null : Number(stackInput.value);
+            this.commitSeatChange(form, player, index);
+        });
+
+        const amountInput = form.querySelector(".amountOverrideInput");
+        amountInput.value = player.amountOverride ?? "";
+        amountInput.addEventListener("input", () => {
+            player.amountOverride = amountInput.value === "" ? null : amountInput.value;
+            this.commitSeatChange(form, player, index);
+        });
+
+        const addFieldBtn = form.querySelector(".addFieldBtn");
+        addFieldBtn.addEventListener("click", () => {
+            player.customFields.push({ label: "", value: "" });
+            this.renderCustomFields(form, player, index);
+            this.hooks.save(this.state);
+        });
+    },
+
+    renderChipCounts(form, player, index) {
+        const container = form.querySelector(".chipCounts");
+        container.innerHTML = "";
+        const template = document.getElementById("chipCountTemplate");
+
+        this.state.chipLegend.forEach(chip => {
+            const row = template.content.firstElementChild.cloneNode(true);
+            row.querySelector(".chipSwatch").style.background = chip.color;
+            row.title = `$${chip.value} chips`;
+            const input = row.querySelector(".chipCountInput");
+            input.value = player.chipCounts[chip.id] || 0;
+            input.addEventListener("input", () => {
+                const count = Math.max(0, Math.floor(Number(input.value)) || 0);
+                player.chipCounts[chip.id] = count;
+                this.commitSeatChange(form, player, index);
+            });
+            container.appendChild(row);
+        });
+    },
+
+    renderCustomFields(form, player, index) {
+        const container = form.querySelector(".customFields");
+        container.innerHTML = "";
+        const template = document.getElementById("customFieldTemplate");
+
+        player.customFields.forEach((field, fieldIdx) => {
+            const row = template.content.firstElementChild.cloneNode(true);
+            const labelInput = row.querySelector(".customFieldLabel");
+            const valueInput = row.querySelector(".customFieldValue");
+            labelInput.value = field.label;
+            valueInput.value = field.value;
+            labelInput.addEventListener("input", () => {
+                field.label = labelInput.value;
+                this.hooks.save(this.state);
+            });
+            valueInput.addEventListener("input", () => {
+                field.value = valueInput.value;
+                this.hooks.save(this.state);
+            });
+            row.querySelector(".removeFieldBtn").addEventListener("click", () => {
+                player.customFields.splice(fieldIdx, 1);
+                this.renderCustomFields(form, player, index);
+                this.hooks.save(this.state);
+            });
+            container.appendChild(row);
+        });
+    },
+
+    // ---- Chip legend ----
+
+    renderChipLegend() {
+        const list = document.getElementById("chipLegendList");
+        list.innerHTML = "";
+        const template = document.getElementById("chipLegendRowTemplate");
+
+        this.state.chipLegend.forEach(chip => {
+            const row = template.content.firstElementChild.cloneNode(true);
+            const colorInput = row.querySelector(".chipColorInput");
+            const valueInput = row.querySelector(".chipValueInput");
+            colorInput.value = chip.color;
+            valueInput.value = chip.value;
+
+            colorInput.addEventListener("input", () => {
+                chip.color = colorInput.value;
+                this.hooks.save(this.state);
+            });
+            valueInput.addEventListener("input", () => {
+                chip.value = Number(valueInput.value) || 0;
+                this.hooks.save(this.state);
+                this.renderSeats();
+                this.renderSeatEditor();
+                this.updatePotBadge();
+            });
+            row.querySelector(".removeChipColorBtn").addEventListener("click", () => {
+                this.state.chipLegend = this.state.chipLegend.filter(c => c.id !== chip.id);
+                this.hooks.save(this.state);
+                this.renderAll();
+            });
+
+            list.appendChild(row);
+        });
+    },
+
+    // ---- Pot breakdown ----
+
+    // Shared by the action bar (live, mid-hand) and the pot wizard (before winners are
+    // picked), because both are showing the dealer the same announcement.
+    buildPotBreakdown(pots, returns, nameFor, heading) {
+        if (pots.length < 2 && returns.length === 0) return null;
+
+        const wrap = document.createElement("div");
+        wrap.className = "potBreakdown";
+
+        if (heading) {
+            const title = document.createElement("p");
+            title.className = "potBreakdownHeading";
+            title.textContent = heading;
+            wrap.appendChild(title);
+        }
+
+        const addRow = (label, amount, who, className) => {
+            const row = document.createElement("div");
+            row.className = `potLayer ${className || ""}`;
+
+            const labelEl = document.createElement("span");
+            labelEl.className = "potLayerLabel";
+            labelEl.textContent = label;
+
+            const amountEl = document.createElement("span");
+            amountEl.className = "potLayerAmount";
+            amountEl.textContent = Money.format(amount);
+
+            const whoEl = document.createElement("span");
+            whoEl.className = "potLayerWho";
+            whoEl.textContent = who;
+
+            row.appendChild(labelEl);
+            row.appendChild(amountEl);
+            row.appendChild(whoEl);
+            wrap.appendChild(row);
+        };
+
+        pots.forEach(pot => addRow(pot.label, pot.amount, pot.eligible.map(nameFor).join(", ")));
+        returns.forEach(ret => addRow("Uncalled", ret.amount, `back to ${nameFor(ret.id)}`, "potLayerReturn"));
+
+        return wrap;
+    },
+
+    // ---- Session standings ----
+
+    renderStandings() {
+        const list = document.getElementById("standingsList");
+        const emptyHint = document.getElementById("standingsEmptyHint");
+        const table = document.getElementById("standingsTable");
+        const standings = HoldemState.sessionStandings(this.state);
+
+        list.innerHTML = "";
+        emptyHint.hidden = standings.length > 0;
+        table.hidden = standings.length === 0;
+
+        const template = document.getElementById("standingsRowTemplate");
+        standings.forEach(row => {
+            const node = template.content.firstElementChild.cloneNode(true);
+            node.querySelector(".standingsName").textContent = row.name;
+            node.querySelector(".standingsIn").textContent = Money.format(row.in);
+            node.querySelector(".standingsWon").textContent = Money.format(row.won);
+
+            const netEl = node.querySelector(".standingsNet");
+            netEl.textContent = Money.formatSigned(row.net);
+            netEl.classList.toggle("netUp", row.net > 0);
+            netEl.classList.toggle("netDown", row.net < 0);
+
+            // What they'd actually be handed if the night ended now: chips in front of
+            // them less the cash they gave the banker. This was computed and written to
+            // the CSV all along, but never shown to the person doing the paying out.
+            const cashEl = node.querySelector(".standingsCashOut");
+            cashEl.textContent = Money.formatSigned(row.cashPosition);
+            cashEl.classList.toggle("netUp", row.cashPosition > 0);
+            cashEl.classList.toggle("netDown", row.cashPosition < 0);
+
+            list.appendChild(node);
+        });
+
+        this.renderBankReconciliation();
+        this.renderSettleUp(standings);
+    },
+
+    // The last step the standings stopped short of. Six signed numbers at 2am is not
+    // the answer to "who pays whom" — it's the arithmetic the dealer still has to do,
+    // and it's the part of the night people actually get wrong.
+    renderSettleUp(standings) {
+        const host = document.getElementById("settleUp");
+        if (!host) return;
+
+        const plan = SettleUp.plan(standings);
+        const note = document.getElementById("settleUpNote");
+        const list = document.getElementById("settleUpList");
+
+        // Nothing to show before anyone is up or down. A panel that says "no payments"
+        // to a table that hasn't played a hand is just noise in the sidebar.
+        host.hidden = plan.payments.length === 0 && plan.balanced;
+        if (host.hidden) return;
+
+        list.innerHTML = "";
+        plan.payments.forEach(payment => {
+            const row = document.createElement("li");
+            row.className = "settleUpRow";
+
+            const who = document.createElement("span");
+            who.className = "settleUpWho";
+            // An arrow rather than "pays": the direction is the whole content of the
+            // line, and it survives being read at a glance from across the table.
+            who.textContent = `${payment.from} → ${payment.to}`;
+            row.appendChild(who);
+
+            const amount = document.createElement("span");
+            amount.className = "settleUpAmount";
+            amount.textContent = Money.format(payment.amount);
+            row.appendChild(amount);
+
+            list.appendChild(row);
+        });
+
+        if (plan.balanced) {
+            const count = plan.payments.length;
+            note.textContent = count === 1
+                ? "One payment and the night is square."
+                : `${count} payments and the night is square.`;
+        } else if (plan.shortBy > 0) {
+            note.textContent =
+                `${Money.format(plan.shortBy)} of winnings has nothing to pay it — there are more chips on the table than cash was taken for. Fix that above before anyone cashes out.`;
+        } else {
+            note.textContent =
+                `${Money.format(plan.overBy)} is owed with nobody to pay it to — more cash was taken than there are chips in play. Fix that above before anyone cashes out.`;
+        }
+        note.classList.toggle("settleUpOff", !plan.balanced);
+    },
+
+    // Does the cash box cover the chips on the table? Nothing asked this before, and
+    // it's the question that decides whether the last two players can be paid.
+    renderBankReconciliation() {
+        const host = document.getElementById("bankReconcile");
+        if (!host) return;
+
+        const bank = HoldemState.bankReconciliation(this.state);
+        // Nothing to reconcile before anybody has handed over money or taken a chip.
+        host.hidden = bank.cashIn === 0 && bank.chipsInPlay === 0;
+        if (host.hidden) return;
+
+        document.getElementById("bankCashIn").textContent = Money.format(bank.cashIn);
+        document.getElementById("bankChipsInPlay").textContent = Money.format(bank.chipsInPlay);
+
+        const verdict = document.getElementById("bankReconcileVerdict");
+        if (bank.balanced) {
+            verdict.textContent = "Balanced — the cash covers every chip on the table.";
+        } else if (bank.difference > 0) {
+            verdict.textContent =
+                `${Money.format(bank.difference)} more in chips than cash taken. Someone's rebuy probably wasn't recorded — the box will be short at cash-out.`;
+        } else {
+            verdict.textContent =
+                `${Money.format(Math.abs(bank.difference))} more cash than chips in play. Someone has paid for chips they haven't been given.`;
+        }
+        verdict.classList.toggle("bankBalanced", bank.balanced);
+        verdict.classList.toggle("bankOff", !bank.balanced);
+    },
+
+    // ---- Hand counter + history ----
+
+    // toLocaleTimeString is the single most expensive call in the history panel, and a
+    // logged hand's timestamp never changes, so the answer is worth keeping.
+    handTimeCache: new Map(),
+
+    formatHandTime(timestamp) {
+        if (this.handTimeCache.has(timestamp)) return this.handTimeCache.get(timestamp);
+        let formatted = "";
+        try {
+            formatted = new Date(timestamp).toLocaleTimeString(undefined, { hour: "2-digit", minute: "2-digit" });
+        } catch {
+            formatted = "";
+        }
+        this.handTimeCache.set(timestamp, formatted);
+        return formatted;
+    },
+
+    // Cheap stand-in for "has the log changed". Entries are immutable once written and
+    // only ever added at the front, so the length, the counter and the newest row
+    // between them catch a recorded hand, a cleared history and an undo.
+    historySignature() {
+        const history = this.state.handHistory || [];
+        const newest = history[0];
+        return [
+            history.length,
+            this.state.handNumber || 1,
+            newest ? newest.handNumber : "",
+            newest ? newest.timestamp : "",
+            newest ? newest.pot : "",
+        ].join("|");
+    },
+
+    // Rebuilding this panel measured 25.7ms of the 30ms a full re-render costs — and a
+    // full re-render runs after every fold, call and raise. The log only changes when a
+    // hand is settled or the history is cleared, perhaps once every thirty taps, so it
+    // is skipped unless it actually did change. Everything else on the table reflects
+    // the current hand and still redraws every time.
+    renderHandHistory(force = false) {
+        const signature = this.historySignature();
+        if (!force && signature === this.lastHistorySignature) return;
+        this.lastHistorySignature = signature;
+
+        document.getElementById("handCounterBadge").textContent = `Hand #${this.state.handNumber || 1}`;
+
+        const list = document.getElementById("handHistoryList");
+        const emptyHint = document.getElementById("handHistoryEmptyHint");
+        const history = this.state.handHistory || [];
+        emptyHint.hidden = history.length > 0;
+        document.getElementById("exportHistoryBtn").disabled = history.length === 0;
+
+        // Built off-document so the panel is laid out once instead of once per row.
+        const fragment = document.createDocumentFragment();
+        const template = document.getElementById("handHistoryRowTemplate");
+        history.forEach(entry => {
+            const row = template.content.firstElementChild.cloneNode(true);
+            row.querySelector(".handHistoryHandNumber").textContent = `Hand #${entry.handNumber}`;
+            row.querySelector(".handHistoryPot").textContent = Money.format(entry.pot);
+            row.querySelector(".handHistoryTime").textContent = this.formatHandTime(entry.timestamp);
+
+            const payoutsEl = row.querySelector(".handHistoryPayouts");
+            payoutsEl.textContent = entry.payouts.map(p => `${p.label} ${Money.format(p.amount)}`).join(", ");
+
+            fragment.appendChild(row);
+        });
+        list.innerHTML = "";
+        list.appendChild(fragment);
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = { Render };
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/seatMenu.js

@@ -0,0 +1,157 @@
+// The long-press menu on a seat. Everything a dealer does to one player mid-hand,
+// one press and one tap away, without opening the full editor and without hunting
+// for whose turn it is in the action bar.
+const SeatMenu = {
+    state: null,
+    hooks: null,
+    seatIndex: null,
+
+    mode: null,
+
+    open(state, hooks, seatIndex) {
+        this.state = state;
+        this.hooks = hooks;
+        this.seatIndex = seatIndex;
+        // Always the action list, never whatever the sheet was showing when it last
+        // closed — a seat menu that opens on a list of chairs is a menu that lost the
+        // dealer's place.
+        this.mode = null;
+        this.render();
+        document.getElementById("seatMenuOverlay").hidden = false;
+    },
+
+    close() {
+        document.getElementById("seatMenuOverlay").hidden = true;
+    },
+
+    // Only the actions that make sense for this seat right now — a folded player has
+    // nothing to go all-in with, and an empty chair has nothing to fold.
+    actionsFor(player, index) {
+        const actions = [];
+        const dealtIn = player.inHand;
+        const live = dealtIn && !player.folded;
+
+        if (live) {
+            actions.push({ label: "Fold", className: "menuDanger", run: () => this.hooks.fold(index) });
+            actions.push({ label: "All-in", className: "menuAccent", run: () => this.hooks.allIn(index) });
+        } else if (dealtIn && player.folded) {
+            actions.push({ label: "Un-fold", run: () => this.hooks.unfold(index) });
+        }
+
+        // The most common interruption in a cash game, and until now it meant opening
+        // the editor and retyping a stack from memory.
+        actions.push({ label: "Add chips…", run: () => this.hooks.addChips(index) });
+
+        actions.push({
+            label: dealtIn ? "Sit out" : "Deal in",
+            run: () => this.hooks.toggleDealtIn(index),
+        });
+
+        if (!this.state.dedicatedDealer && index !== this.state.dealerSeatIndex) {
+            actions.push({ label: "Give the button", run: () => this.hooks.makeDealer(index) });
+        }
+
+        // Naming a blind by hand. Only offered while nothing but the blinds are in —
+        // once somebody has called, moving a blind would mean unpicking a bet that
+        // has already been answered, and that's a decision for the dealer's mouth,
+        // not a menu item. Which blind a seat already has is shown rather than
+        // offered again.
+        if (dealtIn && Betting.onlyBlindsIn(this.state)) {
+            const blinds = HoldemState.getBlindSeats(this.state);
+            if (blinds.sbIndex !== index) {
+                actions.push({ label: "Make small blind", run: () => this.hooks.assignBlind(index, "sb") });
+            }
+            if (blinds.bbIndex !== index) {
+                actions.push({ label: "Make big blind", run: () => this.hooks.assignBlind(index, "bb") });
+            }
+            if (this.state.blindOverride) {
+                actions.push({ label: "Blinds follow the button again", run: () => this.hooks.clearBlindOverride() });
+            }
+        }
+
+        // Changing chairs was drag-and-drop only, and HTML5 drag events are never
+        // generated from a touch screen — so on the device this tool is mostly used on,
+        // the "drag to swap seats" the hint advertised did nothing at all. This is the
+        // same move, by the route a thumb can actually take.
+        if (this.state.seats.length > 1) {
+            actions.push({ label: "Move to…", run: () => this.openMovePicker() });
+        }
+
+        actions.push({ label: "Edit seat…", run: () => this.hooks.editSeat(index) });
+        return actions;
+    },
+
+    // The chairs this player could move to. Every other chair: swapping into an empty
+    // one is how a player moves, and swapping with an occupied one is two players
+    // changing places, which is the other half of the same job.
+    destinationsFor(index) {
+        return this.state.seats
+            .map((player, seat) => ({ player, seat }))
+            .filter(entry => entry.seat !== index);
+    },
+
+    openMovePicker() {
+        this.mode = "move";
+        this.render();
+    },
+
+    render() {
+        const player = this.state.seats[this.seatIndex];
+        const title = document.getElementById("seatMenuTitle");
+        const subtitle = document.getElementById("seatMenuSubtitle");
+        const list = document.getElementById("seatMenuActions");
+        list.innerHTML = "";
+
+        if (this.mode === "move") {
+            title.textContent = `Move ${HoldemState.displayName(player, this.seatIndex)} to…`;
+            subtitle.textContent = "Their chips, cards and bet go with them. The button and the blinds stay on the chair.";
+            this.destinationsFor(this.seatIndex).forEach(({ player: other, seat }) => {
+                const btn = document.createElement("button");
+                btn.type = "button";
+                btn.className = "seatMenuBtn";
+                // displayName falls back to "Seat 5" for a chair with nobody in it,
+                // which reads as "Seat 5 — Seat 5". An empty chair says it's empty.
+                const named = (other.name || "").trim();
+                btn.textContent = named ? `Seat ${seat + 1} — ${named}` : `Seat ${seat + 1} — empty`;
+                btn.addEventListener("click", () => {
+                    const from = this.seatIndex;
+                    this.close();
+                    this.hooks.swapSeats(from, seat);
+                });
+                list.appendChild(btn);
+            });
+            return;
+        }
+
+        title.textContent = HoldemState.displayName(player, this.seatIndex);
+
+        const stack = Betting.stackOf(this.state, player);
+        const owed = Betting.toCall(this.state, player);
+        const bits = [];
+        if (stack > 0) bits.push(`${Money.format(stack)} behind`);
+        if (owed > 0) bits.push(`${Money.format(owed)} to call`);
+        subtitle.textContent = bits.join(" · ");
+
+        this.actionsFor(player, this.seatIndex).forEach(action => {
+            const btn = document.createElement("button");
+            btn.type = "button";
+            btn.className = `seatMenuBtn ${action.className || ""}`;
+            btn.textContent = action.label;
+            btn.addEventListener("click", () => {
+                // "Move to…" stays on the sheet and swaps it for the seat list; every
+                // other action is the end of the interaction.
+                if (action.label === "Move to…") {
+                    action.run();
+                    return;
+                }
+                this.close();
+                action.run();
+            });
+            list.appendChild(btn);
+        });
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = SeatMenu;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/settleUp.js

@@ -0,0 +1,66 @@
+// Who hands cash to whom at the end of the night.
+//
+// The standings panel already works out what everyone is up or down. It then stopped,
+// which leaves the dealer with six signed numbers at 2am and the actual job still to
+// do: turning them into payments. That's the step people get wrong — not the poker.
+//
+// Everything is done in cents. A settlement that has to come out exactly right is the
+// last place to let a float land on 41.99999999.
+const SettleUp = {
+    // Largest debt against largest win, repeatedly. It's greedy rather than optimal,
+    // and for this problem that's the right trade: finding the true minimum number of
+    // transfers is NP-hard, while this is guaranteed to need at most one payment fewer
+    // than there are people, and each payment it does emit clears somebody out of the
+    // list entirely. A dealer wants a short list they can read down, not a proof.
+    //
+    // Payers are the outer loop so that everything one person owes is printed together
+    // — the list is read out loud, one player at a time.
+    plan(standings) {
+        const owed = [];
+        const owing = [];
+
+        (standings || []).forEach(row => {
+            const cents = Money.toCents(row.cashPosition);
+            if (cents > 0) owed.push({ name: row.name, cents });
+            else if (cents < 0) owing.push({ name: row.name, cents: -cents });
+        });
+
+        owed.sort((a, b) => b.cents - a.cents || a.name.localeCompare(b.name));
+        owing.sort((a, b) => b.cents - a.cents || a.name.localeCompare(b.name));
+
+        const payments = [];
+        let creditor = 0;
+        owing.forEach(payer => {
+            while (payer.cents > 0 && creditor < owed.length) {
+                const taker = owed[creditor];
+                const amount = Math.min(payer.cents, taker.cents);
+                payments.push({ from: payer.name, to: taker.name, amount: Money.fromCents(amount) });
+                payer.cents -= amount;
+                taker.cents -= amount;
+                if (taker.cents === 0) creditor++;
+            }
+        });
+
+        // What's left over when the chips on the table don't match the cash that came
+        // in. It is never a rounding artifact — the arithmetic is integer cents — so it
+        // is always the thing the bank check is already warning about: a rebuy nobody
+        // wrote down, or a miscount. Reported rather than quietly spread across the
+        // payments, because inventing a transfer to make the columns agree is how a
+        // real person ends up short.
+        const unpaid = Money.fromCents(owed.reduce((sum, row) => sum + row.cents, 0));
+        const unspent = Money.fromCents(owing.reduce((sum, row) => sum + row.cents, 0));
+
+        return {
+            payments,
+            // Only one of these can be non-zero: either there are more chips than cash
+            // or less, never both.
+            shortBy: unpaid,
+            overBy: unspent,
+            balanced: unpaid === 0 && unspent === 0,
+        };
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = SettleUp;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/shortcuts.js

@@ -0,0 +1,80 @@
+// Keyboard control for a dealer running this on a laptop.
+//
+// The phone has gestures; the desktop had a mouse and nothing else. These are the
+// same actions the bar already offers, reachable without moving a hand to the
+// trackpad between every decision — which is the whole point when the bar is being
+// tapped thirty times a hand.
+const Shortcuts = {
+    // Deliberately single letters with no modifier: a dealer's spare hand rests on
+    // the keyboard, and a chord is slower than reaching for the button would be.
+    KEYS: {
+        f: "fold",
+        c: "checkOrCall",
+        r: "raise",
+        a: "allIn",
+        " ": "advance",
+        enter: "advance",
+        u: "undo",
+        escape: "cancel",
+    },
+
+    mount(handlers) {
+        this.handlers = handlers;
+        document.addEventListener("keydown", e => this.onKey(e));
+    },
+
+    // Nothing fires while the dealer is typing a name, an amount, or a note — the
+    // "c" in "Cass" must not fold the table.
+    isTyping() {
+        const el = document.activeElement;
+        if (!el) return false;
+        const tag = el.tagName;
+        return tag === "INPUT" || tag === "TEXTAREA" || tag === "SELECT" || el.isContentEditable;
+    },
+
+    // An overlay owns the keyboard while it's up. Asking the document which overlays
+    // are open, rather than listing them, means a sheet added later can't quietly
+    // start letting "f" fold the table behind it — the same reason Modal watches for
+    // them instead of being told about each one.
+    overlayOpen() {
+        return [...document.querySelectorAll('[id$="Overlay"]')].some(el => !el.hidden);
+    },
+
+    // Enter and Space are how a keyboard presses the control it is already sitting on.
+    // Claiming them for "advance" didn't just block that press — it ran a different
+    // action instead. Measured: Tab to Resolve Pot, press Enter, and the table dealt
+    // the next hand. Space on the same button worked, because "advance" happened to
+    // decline that time and the browser's own activation got through. A control that
+    // does something else every other press is worse than one that does nothing.
+    //
+    // Only these two keys are handed back. The letter shortcuts stay live with a
+    // button focused, because a button does nothing with "f" and the dealer's hand
+    // shouldn't have to leave them.
+    focusedControlOwnsKey(key) {
+        if (key !== "enter" && key !== " ") return false;
+        const el = document.activeElement;
+        return !!(el && el.matches && el.matches('button, [role="button"], a[href], summary'));
+    },
+
+    onKey(e) {
+        if (e.metaKey || e.ctrlKey || e.altKey) return;
+
+        const key = e.key.length === 1 ? e.key.toLowerCase() : e.key.toLowerCase();
+        const action = this.KEYS[key];
+        if (!action) return;
+
+        if (this.focusedControlOwnsKey(key)) return;
+
+        // Escape is the exception: it should still close the raise pad even if focus
+        // happens to be sitting in its amount field.
+        if (this.isTyping() && !(action === "cancel")) return;
+        if (this.overlayOpen()) return;
+
+        const handled = this.handlers[action] && this.handlers[action]();
+        if (handled) e.preventDefault();
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = Shortcuts;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/splitCalculator.js

@@ -0,0 +1,53 @@
+// Pure math for chopping one pot between tied players. No DOM.
+//
+// A dealer can't push half a chip across the felt, so this works in whole chips of
+// whatever the smallest denomination in play is: everyone gets the same stack, and
+// whatever won't divide is called out separately as odd chips. House rule for those
+// is that they go to the first player left of the button, one at a time.
+const SplitCalculator = {
+    // Everything is done in cents to keep 0.1 + 0.2 out of a payout.
+    toCents(amount) {
+        return Money.toCents(amount);
+    },
+
+    split(potAmount, ways, chipAmount) {
+        const potCents = this.toCents(potAmount);
+        const chipCents = Math.max(1, this.toCents(chipAmount));
+        const players = Math.max(1, Math.floor(Number(ways) || 0));
+
+        if (potCents <= 0) {
+            return { valid: false, each: 0, oddChips: 0, chip: chipCents / 100, dust: 0, players };
+        }
+
+        const wholeChips = Math.floor(potCents / chipCents);
+        // Left over when the pot itself isn't a whole number of the smallest chip —
+        // usually means the dealer picked the wrong denomination, so it's surfaced
+        // rather than silently rolled into someone's stack.
+        const dustCents = potCents - wholeChips * chipCents;
+
+        const chipsEach = Math.floor(wholeChips / players);
+        const oddChips = wholeChips - chipsEach * players;
+
+        return {
+            valid: true,
+            players,
+            each: (chipsEach * chipCents) / 100,
+            oddChips,
+            chip: chipCents / 100,
+            dust: dustCents / 100,
+        };
+    },
+
+    // Sanity check for the UI: what the split actually hands out has to equal the pot.
+    accountedFor(result) {
+        return Money.fromCents(
+            Money.toCents(result.each) * result.players +
+            Money.toCents(result.chip) * result.oddChips +
+            Money.toCents(result.dust)
+        );
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = SplitCalculator;
+}

JoshHeaps.Net/wwwroot/js/casino/holdem/state.js

@@ -0,0 +1,519 @@
+// Table state: seats, chips, blinds, notes. Persisted to localStorage so a dealer's
+// browser refresh mid-game doesn't lose the table.
+const HoldemState = {
+    STORAGE_KEY: "casino.holdem.state.v1",
+    DEFAULT_SEAT_COUNT: 10,
+
+    DEFAULT_CHIP_LEGEND: [
+        { id: "white", color: "#f5f5f5", value: 1 },
+        { id: "red", color: "#c0392b", value: 5 },
+        { id: "green", color: "#1e8449", value: 25 },
+        { id: "black", color: "#111111", value: 100 },
+        { id: "purple", color: "#6c3483", value: 500 },
+    ],
+
+    makeId(prefix) {
+        return `${prefix}-${Date.now().toString(36)}-${Math.random().toString(36).slice(2, 8)}`;
+    },
+
+    makePlayer() {
+        return {
+            id: this.makeId("player"),
+            name: "",
+            inHand: false,
+            folded: false,
+            cards: ["", ""],
+            chipCounts: {},
+            amountOverride: null,
+            customFields: [],
+            // Live-betting fields: chips in front of the player, chips they've put in
+            // on the current street, and whether they've answered the current bet.
+            stack: null,
+            committed: 0,
+            hasActed: false,
+            // Cash handed over tonight, which only moves when they buy chips.
+            buyIns: 0,
+        };
+    },
+
+    MAX_HISTORY_ENTRIES: 200,
+
+    createDefault() {
+        const seatCount = this.DEFAULT_SEAT_COUNT;
+        return {
+            seatCount,
+            direction: "clockwise",
+            basePotAmount: null,
+            dealerSeatIndex: 0,
+            dedicatedDealer: false,
+            chipLegend: this.DEFAULT_CHIP_LEGEND.map(c => ({ ...c })),
+            seats: Array.from({ length: seatCount }, () => this.makePlayer()),
+            notes: "",
+            handNumber: 1,
+            handHistory: [],
+            smallBlind: 1,
+            bigBlind: 2,
+            defaultStack: null,
+            street: "preflop",
+            currentBet: 0,
+            lastRaiseSize: 0,
+            actingSeatIndex: null,
+            // Whether the betting has actually been opened for this hand.
+            //
+            // Dealing and betting used to be one button: "Next Hand" moved the button
+            // and posted the blinds in the same breath. That meant the moment between
+            // hands — the one where people are still sitting down, standing up and
+            // arguing about whose turn it is — was spent with money already committed,
+            // and the blind badges recomputing off `inHand` while the posted chips
+            // stayed frozen from when the hand began. Seat somebody after pressing it
+            // and the table would show a big blind who had posted nothing.
+            //
+            // So the dealer says when. False means the table is being set up: nothing
+            // is committed, the badges are a preview, and seating or moving the button
+            // costs nothing.
+            bettingOpen: false,
+            // Set when the dealer names the blinds by hand instead of letting them
+            // follow the button — { sbIndex, bbIndex }. Home games do this constantly
+            // ("you had it last time", someone arriving late owing a blind), and the
+            // button order is the wrong answer often enough that it has to be
+            // overridable. Cleared at the start of every hand.
+            blindOverride: null,
+        };
+    },
+
+    load() {
+        try {
+            const raw = localStorage.getItem(this.STORAGE_KEY);
+            if (!raw) return this.createDefault();
+            const parsed = JSON.parse(raw);
+            if (!parsed || !Array.isArray(parsed.seats)) return this.createDefault();
+            if (typeof parsed.handNumber !== "number" || parsed.handNumber < 1) parsed.handNumber = 1;
+            if (!Array.isArray(parsed.handHistory)) parsed.handHistory = [];
+
+            // Tables saved before live betting existed are missing its fields; fill
+            // them in rather than making the dealer reset a table mid-session.
+            const defaults = this.createDefault();
+            ["smallBlind", "bigBlind", "defaultStack", "street", "currentBet", "lastRaiseSize",
+                "actingSeatIndex", "blindOverride"]
+                .forEach(key => {
+                    if (parsed[key] === undefined) parsed[key] = defaults[key];
+                });
+
+            // A table saved before dealing and betting were separate has no flag, and
+            // guessing false would show "deal the hand" over a hand already in
+            // progress. Anything already committed, or anyone already on the clock,
+            // means the betting was open when they closed the tab.
+            if (parsed.bettingOpen === undefined) {
+                parsed.bettingOpen =
+                    parsed.actingSeatIndex !== null && parsed.actingSeatIndex !== undefined ||
+                    parsed.seats.some(p =>
+                        (Number(p.committed) || 0) > 0 || (Number(p.amountOverride) || 0) > 0);
+            }
+            parsed.seats.forEach(player => {
+                if (player.stack === undefined) player.stack = null;
+                if (player.committed === undefined) player.committed = 0;
+                if (player.hasActed === undefined) player.hasActed = false;
+                if (player.buyIns === undefined) player.buyIns = 0;
+            });
+
+            return parsed;
+        } catch {
+            return this.createDefault();
+        }
+    },
+
+    save(state) {
+        try {
+            localStorage.setItem(this.STORAGE_KEY, JSON.stringify(state));
+        } catch {
+            // Storage full/unavailable (private browsing, etc.) — the table still works
+            // for the rest of the session, it just won't survive a refresh.
+        }
+    },
+
+    clear() {
+        try {
+            localStorage.removeItem(this.STORAGE_KEY);
+        } catch {
+            // ignore
+        }
+    },
+
+    resizeSeats(state, newCount) {
+        const count = Math.max(2, Math.min(24, Math.floor(newCount) || this.DEFAULT_SEAT_COUNT));
+        const seats = state.seats.slice(0, count);
+        while (seats.length < count) seats.push(this.makePlayer());
+        state.seats = seats;
+        state.seatCount = count;
+        if (state.dealerSeatIndex >= count) state.dealerSeatIndex = 0;
+        return state;
+    },
+
+    // What to call a seat in logs, payouts and standings when the dealer hasn't
+    // typed a name in yet.
+    displayName(player, seatIndex) {
+        return player.name && player.name.trim() ? player.name.trim() : `Seat ${seatIndex + 1}`;
+    },
+
+    // Contribution the table calculator will treat this player as having put in.
+    //
+    // Chips already pushed into the middle count whether or not the player is still
+    // in the hand. Someone who storms off, gets taken out by the dealer, or is
+    // dealt out mid-hand leaves their money on the felt — it's dead money owed to
+    // whoever wins, and it is not theirs to take back. Reading `inHand` first is
+    // how those chips used to disappear out of the pot the instant a seat was
+    // switched off, quietly shrinking the payout by whatever they had posted.
+    computeContribution(player, chipLegend, basePotAmount) {
+        const override = player.amountOverride;
+        if (override !== null && override !== undefined && String(override).trim() !== "") {
+            const parsed = Number(override);
+            if (!Number.isNaN(parsed)) return Math.max(0, parsed);
+        }
+
+        const chipTotal = chipLegend.reduce((sum, chip) => {
+            const count = Number(player.chipCounts[chip.id]) || 0;
+            return sum + count * Number(chip.value || 0);
+        }, 0);
+        if (chipTotal > 0) return chipTotal;
+
+        // The table-wide default is the one thing that stays tied to being dealt in:
+        // it's a stand-in for "everyone put the same amount in", so applying it to
+        // empty chairs would invent a contribution from every seat nobody is using.
+        if (!player.inHand) return 0;
+
+        const base = Number(basePotAmount);
+        return Number.isNaN(base) ? 0 : Math.max(0, base);
+    },
+
+    // Anyone whose chips are in the pot, whether or not they're still in the hand.
+    // A seat that's been switched off mid-hand is dead money: it counts towards the
+    // pot but can never be picked as a winner, exactly like a fold.
+    isDeadMoney(player) {
+        return !player.inHand;
+    },
+
+    // What starting the next hand would take off the table for good: exactly the
+    // fields startNextHand clears.
+    //
+    // Deliberately not totalPot(). The table-wide base pot is a standing ante — a
+    // stand-in for "everyone puts the same in every hand", used by a dealer who
+    // isn't tracking stacks — so it re-applies to the next hand rather than being
+    // lost with this one. Counting it would mean warning about money that isn't
+    // going anywhere, on every single hand, for exactly the dealers who chose the
+    // simplest way to run the table.
+    unresolvedContributions(state) {
+        const total = state.seats.reduce((sum, player) => {
+            const override = player.amountOverride;
+            let banked = 0;
+
+            if (override !== null && override !== undefined && String(override).trim() !== "") {
+                const parsed = Number(override);
+                if (!Number.isNaN(parsed)) banked = Math.max(0, parsed);
+            }
+
+            if (banked === 0) {
+                banked = (state.chipLegend || []).reduce((chips, chip) => {
+                    const count = Number(player.chipCounts[chip.id]) || 0;
+                    return chips + count * Number(chip.value || 0);
+                }, 0);
+            }
+
+            return sum + banked + Math.max(0, Number(player.committed) || 0);
+        }, 0);
+
+        return Money.round(total);
+    },
+
+    totalPot(state) {
+        return state.seats.reduce(
+            (sum, p) => sum + this.computeContribution(p, state.chipLegend, state.basePotAmount),
+            0
+        );
+    },
+
+    // Next occupied-by-index seat in the current blind direction. Every seat index
+    // counts (there's no separate "empty chair" concept) — a dealer running fewer
+    // players just keeps the seat count matched to who's actually sitting down.
+    nextSeatIndex(state, fromIndex, step = 1) {
+        const count = state.seatCount;
+        const delta = state.direction === "counterclockwise" ? -step : step;
+        return ((fromIndex + delta) % count + count) % count;
+    },
+
+    // The button passes to the next player, not the next chair. Moving it one seat at
+    // a time parks it on empty chairs — with four players spread around ten seats it
+    // sits on nobody most hands — and that isn't only untidy: position and blinds are
+    // supposed to come round to each player at the same rate, and they don't if the
+    // button is rotating past chairs nobody is sitting in.
+    advanceButton(state) {
+        for (let step = 1; step <= state.seatCount; step++) {
+            const index = this.nextSeatIndex(state, state.dealerSeatIndex, step);
+            if (state.seats[index].inHand) {
+                state.dealerSeatIndex = index;
+                return;
+            }
+        }
+        // Nobody is dealt in; move it along anyway so it doesn't look stuck.
+        state.dealerSeatIndex = this.nextSeatIndex(state, state.dealerSeatIndex, 1);
+    },
+
+    // Seats dealt into this hand, in blind order starting from the seat after the
+    // button. Blinds follow the players, not the chairs — the seats immediately left
+    // of the button are empty often enough that counting chairs posts them to nobody.
+    liveOrderFromButton(state) {
+        const order = [];
+        for (let step = 1; step <= state.seatCount; step++) {
+            const index = this.nextSeatIndex(state, state.dealerSeatIndex, step);
+            if (state.seats[index].inHand) order.push(index);
+        }
+        return order;
+    },
+
+    // A button sitting on an empty chair is only cosmetic until you try to read
+    // position off it. On the very first hand of a fresh table it starts on seat 1
+    // whether or not anybody is sitting there, and a table that empties out around it
+    // leaves it stranded. Move it to a real player before a hand is dealt.
+    // Where the button will be when the hand is dealt — without moving it.
+    //
+    // Kept separate from ensureButtonOnPlayer because the deal preview has to be able
+    // to ask the question without answering it. It couldn't, and so the preview lied:
+    // with the button parked on an empty chair it promised one pair of blinds and
+    // dealing produced another, because beginHand relocates the button first and then
+    // works out who posts.
+    buttonSeatForDeal(state) {
+        const seated = state.seats[state.dealerSeatIndex];
+        if (seated && seated.inHand) return state.dealerSeatIndex;
+        for (let step = 0; step < state.seatCount; step++) {
+            const index = this.nextSeatIndex(state, state.dealerSeatIndex, step);
+            if (state.seats[index].inHand) return index;
+        }
+        return state.dealerSeatIndex;
+    },
+
+    ensureButtonOnPlayer(state) {
+        state.dealerSeatIndex = this.buttonSeatForDeal(state);
+    },
+
+    // A hand-picked blind is only usable if that seat is actually in the hand — a
+    // dealer who names a blind and then deals that player out shouldn't have the
+    // table quietly post to nobody.
+    validBlindOverride(state) {
+        const o = state.blindOverride;
+        if (!o) return null;
+        const ok = i => Number.isInteger(i) && i >= 0 && i < state.seatCount && state.seats[i] && state.seats[i].inHand;
+        if (!ok(o.sbIndex) || !ok(o.bbIndex) || o.sbIndex === o.bbIndex) return null;
+        return o;
+    },
+
+    // Who posts what. Heads-up is its own rule: with two players the button posts the
+    // small blind, which is the opposite of the usual order.
+    getBlindSeats(state) {
+        const live = this.liveOrderFromButton(state);
+        const dealerIndex = state.dealerSeatIndex;
+
+        // A blind the dealer named by hand wins over anything positional. Heads-up is
+        // still reported honestly so the betting order stays right — who posts what
+        // is the dealer's call, but two-handed play acting in reverse is a rule.
+        const override = this.validBlindOverride(state);
+        if (override) {
+            return {
+                dealerIndex,
+                sbIndex: override.sbIndex,
+                bbIndex: override.bbIndex,
+                headsUp: live.length === 2,
+                manual: true,
+            };
+        }
+
+        if (live.length < 2) {
+            return { dealerIndex, sbIndex: null, bbIndex: null, headsUp: false };
+        }
+
+        if (live.length === 2) {
+            const buttonIsPlaying = state.seats[dealerIndex].inHand;
+            const sbIndex = buttonIsPlaying ? dealerIndex : live[0];
+            const bbIndex = live.find(i => i !== sbIndex);
+            return { dealerIndex, sbIndex, bbIndex, headsUp: true };
+        }
+
+        return { dealerIndex, sbIndex: live[0], bbIndex: live[1], headsUp: false };
+    },
+
+    startNextHand(state) {
+        this.advanceButton(state);
+        // Cards aren't out and nothing is posted until the dealer says so.
+        state.bettingOpen = false;
+        state.actingSeatIndex = null;
+        state.street = "preflop";
+        state.currentBet = 0;
+        state.lastRaiseSize = 0;
+        // A hand-picked blind applies to the hand it was picked for. Carrying it into
+        // the next one would freeze the blinds on two players for the rest of the
+        // night, which is the opposite of what naming them once is for.
+        state.blindOverride = null;
+        state.seats.forEach(p => {
+            p.folded = false;
+            p.cards = ["", ""];
+            p.chipCounts = {};
+            p.amountOverride = null;
+            p.committed = 0;
+            p.hasActed = false;
+        });
+        // Anyone who joined mid-hand is a full player again from here.
+        this.ensureButtonOnPlayer(state);
+    },
+
+    // Appends a resolved-pot record to the running session log a dealer can point to
+    // for chip-count disputes, then advances the hand counter. `payouts` is
+    // [{ id, label, amount }, ...] — who got paid what out of this hand's pot(s).
+    //
+    // Must be called before startNextHand() clears the seats: the per-player `ledger`
+    // it stores alongside the payouts is what session standings are summed from later,
+    // and it needs this hand's contributions while they're still on the table.
+    recordHand(state, payouts) {
+        if (typeof state.handNumber !== "number") state.handNumber = 1;
+        if (!Array.isArray(state.handHistory)) state.handHistory = [];
+
+        const pot = payouts.reduce((sum, p) => sum + p.amount, 0);
+        const wonById = new Map(payouts.map(p => [p.id, p.amount]));
+        const ledger = state.seats
+            .map((player, index) => ({
+                id: player.id,
+                name: this.displayName(player, index),
+                in: this.computeContribution(player, state.chipLegend, state.basePotAmount),
+                won: wonById.get(player.id) || 0,
+            }))
+            .filter(row => row.in > 0 || row.won > 0);
+
+        state.handHistory.unshift({
+            handNumber: state.handNumber,
+            timestamp: Date.now(),
+            pot,
+            payouts,
+            ledger,
+        });
+        if (state.handHistory.length > this.MAX_HISTORY_ENTRIES) {
+            state.handHistory.length = this.MAX_HISTORY_ENTRIES;
+        }
+        state.handNumber += 1;
+    },
+
+    clearHistory(state) {
+        state.handHistory = [];
+        state.handNumber = 1;
+    },
+
+    // Running per-player totals for the whole session, so a dealer settling up at the
+    // end of the night reads one number per person instead of adding up every hand.
+    // Keyed by seat id, which survives renames and reseating; hands recorded before
+    // the ledger existed simply don't contribute to the totals.
+    sessionStandings(state) {
+        const totals = new Map();
+
+        (state.handHistory || []).forEach(entry => {
+            (entry.ledger || []).forEach(row => {
+                // History is newest-first, so the first name seen for an id is the
+                // most recent one the dealer typed.
+                const running = totals.get(row.id) || { id: row.id, name: row.name, in: 0, won: 0 };
+                running.in += row.in;
+                running.won += row.won;
+                totals.set(row.id, running);
+            });
+        });
+
+        // Cash bought in and chips currently in front don't come from the hand log at
+        // all, so they're read off the seat rather than summed — a rebuy isn't a hand.
+        const seatById = new Map(state.seats.map(p => [p.id, p]));
+
+        // Anyone who has money in the game belongs in the settle-up, whether or not
+        // they've been in a logged hand yet. Building the list from the hand log alone
+        // left a player who bought in and then sat through a few hands folding —
+        // or who just sat down — missing entirely, so the banker's own record didn't
+        // mention the cash they'd taken. They turn up at cash-out holding chips the
+        // list never accounted for.
+        state.seats.forEach((player, index) => {
+            if (totals.has(player.id)) return;
+            const hasMoneyInPlay =
+                (Number(player.buyIns) || 0) > 0 ||
+                (Number(player.stack) || 0) > 0 ||
+                (Number(player.amountOverride) || 0) > 0 ||
+                (Number(player.committed) || 0) > 0;
+            if (!hasMoneyInPlay) return;
+            totals.set(player.id, { id: player.id, name: this.displayName(player, index), in: 0, won: 0 });
+        });
+
+        return Array.from(totals.values())
+            .map(t => {
+                const seat = seatById.get(t.id);
+                const boughtIn = seat ? Money.round(Number(seat.buyIns) || 0) : 0;
+                const chipsNow = seat ? Money.round(Number(seat.stack) || 0) : 0;
+                // Chips already pushed into the hand in progress are still this
+                // player's money until it's won. Leaving them out makes the cash
+                // position disagree with the hand log for as long as a hand is open —
+                // and blinds are posted the instant the previous one settles, so that
+                // window is almost always.
+                const inFrontOfThem = seat ? (Number(seat.amountOverride) || 0) + (Number(seat.committed) || 0) : 0;
+
+                return {
+                    ...t,
+                    in: Money.round(t.in),
+                    won: Money.round(t.won),
+                    net: Money.round(t.won - t.in),
+                    boughtIn,
+                    chipsNow,
+                    cashPosition: Money.round(chipsNow + inFrontOfThem - boughtIn),
+                };
+            })
+            .sort((a, b) => b.net - a.net);
+    },
+
+    // Two players change chairs.
+    //
+    // The whole seat moves — name, stack, cards, what they have in the pot — because
+    // that is what changing chairs is. What stays behind is everything that belongs to
+    // the *position*: the button, the blinds and the acting index all name a chair, and
+    // a player who moves into the big blind's chair is the big blind. That is the same
+    // answer a card room gives.
+    swapSeats(state, a, b) {
+        const seats = state.seats || [];
+        if (a === b) return false;
+        if (!seats[a] || !seats[b]) return false;
+        [seats[a], seats[b]] = [seats[b], seats[a]];
+        return true;
+    },
+
+    // The one check a banker actually needs, and the one nothing here did.
+    //
+    // Every chip on the table is a promise to pay cash for it later. If the chips in
+    // play add up to more than the cash that came in, that promise can't be kept —
+    // and the way you find out is the last two players cashing out and the box being
+    // empty. It's always someone taking chips without paying, a rebuy that never got
+    // recorded, or a miscount, and it's silent until it's too late to work out which.
+    //
+    // Chips in play counts everything a player could hand back: what's in front of
+    // them and what's in the middle waiting to be won.
+    bankReconciliation(state) {
+        const cashIn = state.seats.reduce((sum, p) => sum + Math.max(0, Number(p.buyIns) || 0), 0);
+        const chipsInPlay = state.seats.reduce(
+            (sum, p) =>
+                sum +
+                Math.max(0, Number(p.stack) || 0) +
+                Math.max(0, Number(p.committed) || 0) +
+                Math.max(0, Number(p.amountOverride) || 0),
+            0
+        );
+
+        const difference = Money.round(chipsInPlay - cashIn);
+        return {
+            cashIn: Money.round(cashIn),
+            chipsInPlay: Money.round(chipsInPlay),
+            difference,
+            // Half a cent of float dust isn't a discrepancy worth alarming anyone over.
+            balanced: Math.abs(difference) <= Money.EPSILON,
+        };
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = HoldemState;
+}

native/chess_engine/include/chess_engine.h

@@ -32,6 +32,9 @@ extern "C" {                          /* prevent C++ name mangling */
  * Internally it points to your engine state object. */
 typedef struct ChessEngine* EngineHandle;
 
+/* Opaque per-game training accumulator (see the learned-weights ABI at the bottom). */
+typedef struct Trainer* TrainerHandle;
+
 /* Return codes. 0 == success; negative == error. Keep these values stable. */
 enum {
     CHESS_OK              =  0,
@@ -79,6 +82,36 @@ CHESS_API int CHESS_CALL engine_version(char* out_buf, int out_len);
 /* Destroy an instance created by engine_create. Safe to call with NULL. */
 CHESS_API void CHESS_CALL engine_destroy(EngineHandle engine);
 
+/* ---- Learned-weights / training ABI ----
+ * The learned engine's weights live process-globally here. The host orchestrates games but
+ * owns no chess logic: it points the engine at the weights file, records each played
+ * position, and applies the game's result. */
+
+/* Load the global learned weights from `path` and remember it for later saves. Idempotent;
+ * a missing/short file leaves the weights neutral. Call once before learned play/training. */
+CHESS_API void CHESS_CALL learned_load(const char* path);
+
+/* Copy the global weights out for visualization: 6*64 midgame + 6*64 endgame (PAWN..KING,
+ * squares 0..63) + feature weights. Returns the count written, or CHESS_ERR_BUFFER if
+ * out_len is too small (needs >= 776). */
+CHESS_API int CHESS_CALL weights_snapshot(int* out, int out_len);
+
+/* Create / destroy a per-game training accumulator. Safe to destroy NULL. */
+CHESS_API TrainerHandle CHESS_CALL trainer_create(void);
+CHESS_API void          CHESS_CALL trainer_destroy(TrainerHandle trainer);
+
+/* Record one played position (post-move FEN) into the accumulator. */
+CHESS_API void CHESS_CALL trainer_record(TrainerHandle trainer, const char* fen);
+
+/* Apply a finished game's outcome to the global weights and save. Each touched cell (a piece
+ * on a square, or a feature) tracks a presence-weighted running average of the game's
+ * "advantage" — the game's outcome (scaled by `weight`, e.g. 0.5 for a material-imbalance
+ * draw) minus how much of that outcome the winner's average material edge already explains —
+ * so mg/eg/featW end up as a fractional win-rate (percent of games won with that piece there,
+ * minus percent lost), not an unbounded plus/minus tally, and a piece doesn't get credit
+ * merely for existing on the winning side of a material blowout. winner: 0 = white, 1 = black. */
+CHESS_API void CHESS_CALL trainer_apply(TrainerHandle trainer, int winner, double weight);
+
 #ifdef __cplusplus
 }
 #endif

native/chess_engine/src/chess_engine.cpp

@@ -20,10 +20,13 @@
 
 #include <algorithm>
 #include <atomic>
+#include <cmath>
 #include <cstdint>
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
+#include <fstream>
+#include <iomanip>
 #include <mutex>
 #include <new>
 #include <string>
@@ -76,10 +79,79 @@ static chess::Move tt_move (uint64_t d) { return chess::Move(static_cast<uint16_
 static int         tt_depth(uint64_t d) { return static_cast<int>(static_cast<uint8_t>(d >> 48)); }
 static Bound       tt_bound(uint64_t d) { return static_cast<Bound>(static_cast<uint8_t>(d >> 56)); }
 
-/* Internal engine state. One ChessEngine = one game. The table is NOT here: it is the
- * shared g_tt above. */
+/* Eval variant for an engine handle. CLASSIC = the hand-crafted evaluate(); LEARNED =
+ * material + learned phase-split piece-square tables + learned feature weights. */
+enum EvalVariant : int { EVAL_CLASSIC = 0, EVAL_LEARNED = 1 };
+
+/* The learned feature knobs (beyond the piece-square tables). Each has one weight learned
+ * from game outcomes; its activation is computed by compute_features(). Mobility is per
+ * piece type. Order is fixed — it is the on-disk and snapshot layout after the two tables. */
+enum Feature : int {
+    FEAT_MOB_N, FEAT_MOB_B, FEAT_MOB_R, FEAT_MOB_Q,   /* legal-move counts, per piece type */
+    FEAT_PASSED,                                       /* passed pawns, endgame-weighted     */
+    FEAT_ISOLATED,                                     /* isolated pawns                     */
+    FEAT_DOUBLED,                                       /* doubled pawns                      */
+    FEAT_KING,                                          /* king pawn-shelter, midgame-weighted */
+    FEATURE_NB
+};
+
+/* Per-handle eval configuration, snapshotted from the global learned weights at
+ * engine_create so the search reads a stable copy. The tables are white-relative: a black
+ * piece indexes the rank-mirrored square (sq ^ 56). `mg`/`eg` are blended by game phase.
+ * Indexed by chess::PieceType (PAWN..KING). Only consulted when variant == EVAL_LEARNED. */
+struct EvalParams {
+    int variant = EVAL_CLASSIC;
+    int mg[chess::PIECE_TYPE_NB][64] = {};
+    int eg[chess::PIECE_TYPE_NB][64] = {};
+    int featW[FEATURE_NB] = {};
+};
+
+/* Internal engine state. One ChessEngine = one game. The transposition table is NOT
+ * here: it is the shared g_tt above. */
 struct ChessEngine {
-    int skill = 20;          /* 1..20 from the UI; controls search depth */
+    int        skill = 20;   /* 1..20 from the UI; controls search depth */
+    EvalParams eval;         /* which evaluation the search uses, plus any learned weights */
+};
+
+/* The process-global learned weights: the single source of truth, loaded from disk once and
+ * updated in place by training. Engine handles snapshot it at creation; the visualization
+ * snapshots it on demand. Guarded by g_weightsMutex for updates/saves (eval reads its own
+ * per-handle copy, so it never touches this concurrently).
+ *
+ * mg/eg/featW are DERIVED, not accumulated: each is always exactly OUT_SCALE * (score/visits)
+ * for its cell (see trainer_apply), recomputed whenever that cell's stats change. visits is
+ * the presence-weighted count of games that touched the cell (how much to trust the average);
+ * score is the presence-weighted sum of each game's material-adjusted advantage (see
+ * trainer_apply) — so score/visits is literally "fraction of (presence-weighted) games won
+ * with this piece here, minus fraction lost," bounded to [-1,1] by construction. */
+struct LearnedWeights {
+    int mg[chess::PIECE_TYPE_NB][64] = {};
+    int eg[chess::PIECE_TYPE_NB][64] = {};
+    int featW[FEATURE_NB] = {};
+
+    double mgVisits[chess::PIECE_TYPE_NB][64] = {};
+    double mgScore [chess::PIECE_TYPE_NB][64] = {};
+    double egVisits[chess::PIECE_TYPE_NB][64] = {};
+    double egScore [chess::PIECE_TYPE_NB][64] = {};
+    double featVisits[FEATURE_NB] = {};
+    double featScore [FEATURE_NB] = {};
+};
+
+static LearnedWeights g_weights;
+static std::mutex     g_weightsMutex;
+static std::string    g_weightsPath;
+
+/* Per-game training accumulator (one per learned CPU-vs-CPU game). Records, per ply, where
+ * each side's pieces sat (split into midgame/endgame by phase), each side's feature
+ * activations, and the white-minus-black material balance; trainer_apply turns the totals
+ * into a presence-weighted update to the running per-cell averages. Squares are white-relative
+ * (black indexes sq ^ 56), so a side's tally lines up with the shared white-relative table. */
+struct Trainer {
+    double mgOcc[chess::COLOR_NB][chess::PIECE_TYPE_NB][64] = {};
+    double egOcc[chess::COLOR_NB][chess::PIECE_TYPE_NB][64] = {};
+    double featAcc[chess::COLOR_NB][FEATURE_NB] = {};
+    double matDiffAcc = 0.0;      /* sum over plies of (white material - black material), cp */
+    int    plies = 0;
 };
 
 static int copy_out(const char* src, char* out_buf, int out_len) {
@@ -108,6 +180,83 @@ static int parse_skill(const char* options, int fallback) {
     return v < 1 ? 1 : v > 20 ? 20 : v;
 }
 
+/* "variant=learned" in the options selects the learned eval; anything else is classic. */
+static int parse_variant(const char* options) {
+    if (!options) return EVAL_CLASSIC;
+    const char* p = std::strstr(options, "variant=");
+    if (!p) return EVAL_CLASSIC;
+    return std::strncmp(p + 8, "learned", 7) == 0 ? EVAL_LEARNED : EVAL_CLASSIC;
+}
+
+/* On-disk format: 6*64 mg ints (PAWN..KING, squares 0..63), then 6*64 eg ints, then
+ * FEATURE_NB feature ints, then the backing visits/score doubles for each (mgVisits, mgScore,
+ * egVisits, egScore, featVisits, featScore) in the same shapes, all whitespace-separated. A
+ * missing file or short read leaves the rest neutral (0), so an absent weights file just means
+ * "train from a blank slate" — and a file written by the pre-fractional-learning format (which
+ * ends after the feature ints) loads its mg/eg/featW fine and simply starts every cell's
+ * visits/score history fresh from the next game that touches it. Caller holds g_weightsMutex. */
+static void load_global_weights(const char* path) {
+    g_weights = LearnedWeights{};                    /* reset to neutral before loading */
+
+    if (!path || !*path) return;
+    std::ifstream f(path);
+    if (!f) return;
+
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq)
+            if (!(f >> g_weights.mg[pt][sq])) return;
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq)
+            if (!(f >> g_weights.eg[pt][sq])) return;
+    for (int i = 0; i < FEATURE_NB; ++i)
+        if (!(f >> g_weights.featW[i])) return;
+
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq)
+            if (!(f >> g_weights.mgVisits[pt][sq])) return;
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq)
+            if (!(f >> g_weights.mgScore[pt][sq])) return;
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq)
+            if (!(f >> g_weights.egVisits[pt][sq])) return;
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq)
+            if (!(f >> g_weights.egScore[pt][sq])) return;
+    for (int i = 0; i < FEATURE_NB; ++i)
+        if (!(f >> g_weights.featVisits[i])) return;
+    for (int i = 0; i < FEATURE_NB; ++i)
+        if (!(f >> g_weights.featScore[i])) return;
+}
+
+/* Persist g_weights to g_weightsPath in the format load_global_weights reads. Full round-trip
+ * precision on the doubles (visits/score are running sums that keep accumulating across many
+ * games, so truncating them would drift the derived mg/eg/featW over time). Caller holds the
+ * lock. */
+static void save_global_weights() {
+    if (g_weightsPath.empty()) return;
+    std::ofstream f(g_weightsPath);
+    if (!f) return;
+
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq) f << g_weights.mg[pt][sq] << (sq == 63 ? '\n' : ' ');
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq) f << g_weights.eg[pt][sq] << (sq == 63 ? '\n' : ' ');
+    for (int i = 0; i < FEATURE_NB; ++i) f << g_weights.featW[i] << (i == FEATURE_NB - 1 ? '\n' : ' ');
+
+    f << std::setprecision(17);
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq) f << g_weights.mgVisits[pt][sq] << (sq == 63 ? '\n' : ' ');
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq) f << g_weights.mgScore[pt][sq] << (sq == 63 ? '\n' : ' ');
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq) f << g_weights.egVisits[pt][sq] << (sq == 63 ? '\n' : ' ');
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq) f << g_weights.egScore[pt][sq] << (sq == 63 ? '\n' : ' ');
+    for (int i = 0; i < FEATURE_NB; ++i) f << g_weights.featVisits[i] << (i == FEATURE_NB - 1 ? '\n' : ' ');
+    for (int i = 0; i < FEATURE_NB; ++i) f << g_weights.featScore[i] << (i == FEATURE_NB - 1 ? '\n' : ' ');
+}
+
 /* Maps the 1..20 difficulty to a search depth. Kept modest: the search has no
  * quiescence yet, so deep fixed-depth runs get expensive quickly. */
 static int depth_for_skill(int skill) {
@@ -208,14 +357,32 @@ static int evaluatePawn(const chess::Position& pos, const chess::Color c, const
     return score;
 }
 
+static int piece_value(chess::PieceType pt) {
+    switch (pt) {
+    case chess::PAWN:   return 100;
+    case chess::KNIGHT: return 320;
+    case chess::BISHOP: return 330;
+    case chess::ROOK:   return 500;
+    case chess::QUEEN:  return 900;
+    default:            return 0;
+    }
+}
+
 static int castleIncentive(const chess::Position& pos, chess::Color c) {
-    if (!pos.pieces(chess::QUEEN))
-        return 0;
+    chess::Bitboard pcs = pos.pieces();
+    int total = 0;
+    while (pcs) {
+        chess::Square s = chess::pop_lsb(pcs);
+        chess::Piece pc = pos.piece_on(s);
+        chess::Color c = chess::color_of(pc);
+        total += piece_value(chess::type_of(pc));
+    }
+
     chess::Square k = pos.king_square(c);
     bool castled = (c == chess::WHITE) ? (k == chess::G1 || k == chess::C1)
         : (k == chess::G8 || k == chess::C8);
 
-    return castled ? 600 : 0;
+    return castled ? (total / 10) : 0;
 }
 
 static int evaluatePiece(const chess::Position& pos, const chess::Square& s, const chess::Piece& pc, const chess::Color& c) {
@@ -261,10 +428,141 @@ static int evaluate(const chess::Position& pos) {
     return score;
 }
 
+/* ---- Learned (phase-split tables + feature knobs) evaluation ---------------------------
+ * The model is a linear combination of features whose weights are learned from outcomes:
+ *   eval = Σ pieces [ material + blend(mg, eg, phase) ]  +  Σ features featW[i]·activation[i]
+ * compute_features() is the single source of feature activations, used by BOTH the eval here
+ * and the trainer, so the two can never disagree. Constants below are the only tunables. */
+
+/* Per-game-outcome learning constants. Squares and features both learn a presence/activation-
+ * weighted AVERAGE advantage in [-1,1] (see trainer_apply) — OUT_SCALE just converts that
+ * average into a centipawn-ish int for the eval/table to add directly. FEAT_SCALE normalizes
+ * each feature's raw per-ply activation to a comparable magnitude before it's used as a weight
+ * (so high-count mobility doesn't dwarf the small pawn-structure terms), same as before.
+ * MATERIAL_ELO_SCALE is the classic centipawn-to-win-probability curve
+ * (expected = 1/(1+10^(-cp/400))) used to compute how much of a result material already
+ * explains, so training credits placement/features only for the part of the result that
+ * material didn't already predict. */
+static constexpr int    SQ_OUT_SCALE      = 250;
+static constexpr int    FEAT_OUT_SCALE    = 500;
+static constexpr double MATERIAL_ELO_SCALE = 400.0;
+static constexpr double FEAT_SCALE[FEATURE_NB] = { 4, 6, 8, 14, 2, 1, 1, 2 };
+
+/* Game phase in [0,1] from remaining non-pawn material (PeSTO weights N=B=1, R=2, Q=4; max
+ * 24 for both full sides): 0 = opening, 1 = bare kings. Drives the mg/eg table blend and
+ * the phase weighting of the passed-pawn (×phase) and king-safety (×(1−phase)) features. */
+static double game_phase(const chess::Position& pos) {
+    int npm = chess::popcount(pos.pieces(chess::KNIGHT)) * 1
+            + chess::popcount(pos.pieces(chess::BISHOP)) * 1
+            + chess::popcount(pos.pieces(chess::ROOK))   * 2
+            + chess::popcount(pos.pieces(chess::QUEEN))  * 4;
+    constexpr int MAX = 24;
+    if (npm >= MAX) return 0.0;
+    return double(MAX - npm) / MAX;
+}
+
+/* Blend a midgame and endgame value by phase, rounding per-piece (so training credits a
+ * square the same way the eval reads it). */
+static int blend(int mg, int eg, double phase) {
+    return int(std::lround((1.0 - phase) * mg + phase * eg));
+}
+
+/* Fills `out[FEATURE_NB]` with one color's raw feature activations for a position. The piece-
+ * square tables handle "where pieces belong"; these capture context a static table can't:
+ * legal mobility (per piece type, so pins reduce it), passed pawns (endgame-weighted), pawn
+ * structure, and king shelter (midgame-weighted). Ported nowhere — this is the only copy. */
+static void compute_features(chess::Position& pos, chess::Color c, double phase, double out[FEATURE_NB]) {
+    for (int i = 0; i < FEATURE_NB; ++i) out[i] = 0.0;
+
+    /* Mobility: legal moves for color c, bucketed by the moving piece's type. */
+    chess::MoveList moves;
+    pos.generate_legal_for(c, moves);
+    for (int i = 0; i < moves.size(); ++i) {
+        switch (chess::type_of(pos.piece_on(moves.moves[i].from()))) {
+            case chess::KNIGHT: out[FEAT_MOB_N] += 1; break;
+            case chess::BISHOP: out[FEAT_MOB_B] += 1; break;
+            case chess::ROOK:   out[FEAT_MOB_R] += 1; break;
+            case chess::QUEEN:  out[FEAT_MOB_Q] += 1; break;
+            default: break;
+        }
+    }
+
+    /* Pawn structure. */
+    chess::Bitboard pawns = pos.pieces(c, chess::PAWN);
+    chess::Bitboard bb = pawns;
+    while (bb) {
+        chess::Square s = chess::pop_lsb(bb);
+
+        if (!(front_span(c, s) & pos.pieces(~c, chess::PAWN))) {          /* passed */
+            chess::Rank r = chess::rank_of(s);
+            int toPromotion = (c == chess::WHITE) ? (chess::RANK_8 - r) : (r - chess::RANK_1);
+            out[FEAT_PASSED] += (6 - toPromotion) * phase;               /* 0..5 ranks advanced, late-game */
+        }
+        if (front_span_file_only(c, s) & pawns)                          /* doubled (friendly pawn ahead) */
+            out[FEAT_DOUBLED] += 1;
+
+        chess::File f = chess::file_of(s);
+        chess::Bitboard adjacent = 0;
+        if (f > chess::FILE_A) adjacent |= chess::file_bb(chess::File(f - 1));
+        if (f < chess::FILE_H) adjacent |= chess::file_bb(chess::File(f + 1));
+        if (!(adjacent & pawns))                                          /* isolated */
+            out[FEAT_ISOLATED] += 1;
+    }
+
+    /* King safety: friendly pawns sheltering the king (its file + adjacent files, the two
+     * ranks in front), worth more in the midgame. */
+    chess::Square k = pos.king_square(c);
+    chess::File kf = chess::file_of(k);
+    chess::Rank kr = chess::rank_of(k);
+    chess::Bitboard kingFiles = chess::file_bb(kf);
+    if (kf > chess::FILE_A) kingFiles |= chess::file_bb(chess::File(kf - 1));
+    if (kf < chess::FILE_H) kingFiles |= chess::file_bb(chess::File(kf + 1));
+    chess::Bitboard shelterRanks = 0;
+    for (int d = 1; d <= 2; ++d) {
+        int rr = (c == chess::WHITE) ? (kr + d) : (kr - d);
+        if (rr >= 0 && rr <= 7) shelterRanks |= (0xFFULL << (8 * rr));
+    }
+    out[FEAT_KING] += chess::popcount(kingFiles & shelterRanks & pawns) * (1.0 - phase);
+}
+
+/* Learned eval (white-positive/absolute, like evaluate()): material + phase-blended piece-
+ * square tables + learned feature weights. Black pieces index the rank-mirrored square
+ * (s ^ 56) so both colors share one white-relative table. Non-const because mobility
+ * generates legal moves (which the position's move generator does via do/undo). */
+static int evaluateLearned(chess::Position& pos, const EvalParams& ep) {
+    double phase = game_phase(pos);
+    int score = 0;
+
+    chess::Bitboard white = pos.pieces(chess::WHITE);
+    while (white) {
+        chess::Square s = chess::pop_lsb(white);
+        chess::PieceType pt = chess::type_of(pos.piece_on(s));
+        score += piece_value(pt) + blend(ep.mg[pt][s], ep.eg[pt][s], phase);
+    }
+
+    chess::Bitboard black = pos.pieces(chess::BLACK);
+    while (black) {
+        chess::Square s = chess::pop_lsb(black);
+        chess::PieceType pt = chess::type_of(pos.piece_on(s));
+        score -= piece_value(pt) + blend(ep.mg[pt][s ^ 56], ep.eg[pt][s ^ 56], phase);
+    }
+
+    double wFeat[FEATURE_NB], bFeat[FEATURE_NB];
+    compute_features(pos, chess::WHITE, phase, wFeat);
+    compute_features(pos, chess::BLACK, phase, bFeat);
+
+    double feature = 0.0;
+    for (int i = 0; i < FEATURE_NB; ++i)
+        feature += ep.featW[i] * (wFeat[i] - bFeat[i]) / FEAT_SCALE[i];
+    score += int(std::lround(feature));
+
+    return score;
+}
+
 /* evaluate() is white-positive (absolute). Negamax needs it relative to the side to
  * move, so flip the sign when black is to move. */
-static int evaluate_stm(const chess::Position& pos, bool whiteToMove) {
-    int s = evaluate(pos);
+static int evaluate_stm(chess::Position& pos, bool whiteToMove, const EvalParams& ep) {
+    int s = (ep.variant == EVAL_LEARNED) ? evaluateLearned(pos, ep) : evaluate(pos);
     return whiteToMove ? s : -s;
 }
 
@@ -274,17 +572,6 @@ static int evaluate_stm(const chess::Position& pos, bool whiteToMove) {
 static int score_to_tt(int s, int ply)   { return s >=  MATE_BOUND ? s + ply : s <= -MATE_BOUND ? s - ply : s; }
 static int score_from_tt(int s, int ply) { return s >=  MATE_BOUND ? s - ply : s <= -MATE_BOUND ? s + ply : s; }
 
-static int piece_value(chess::PieceType pt) {
-    switch (pt) {
-        case chess::PAWN:   return 100;
-        case chess::KNIGHT: return 320;
-        case chess::BISHOP: return 330;
-        case chess::ROOK:   return 500;
-        case chess::QUEEN:  return 900;
-        default:            return 0;
-    }
-}
-
 /* Heuristic for searching the most promising moves first, which makes alpha-beta prune far
  * more. Bands, highest first: the TT best move, then captures by MVV-LVA (most valuable
  * victim, least valuable attacker), then the two killer moves for this ply (quiet moves that
@@ -351,6 +638,15 @@ CHESS_API EngineHandle CHESS_CALL engine_create(const char* options) {
     auto* e = new (std::nothrow) ChessEngine();
     if (!e) return nullptr;
     e->skill = parse_skill(options, e->skill);
+    e->eval.variant = parse_variant(options);
+    if (e->eval.variant == EVAL_LEARNED) {
+        /* Snapshot the current global weights so the search reads a stable copy (training
+         * updates the global between games; the weights path is owned by learned_load). */
+        std::lock_guard<std::mutex> lock(g_weightsMutex);
+        std::memcpy(e->eval.mg,    g_weights.mg,    sizeof e->eval.mg);
+        std::memcpy(e->eval.eg,    g_weights.eg,    sizeof e->eval.eg);
+        std::memcpy(e->eval.featW, g_weights.featW, sizeof e->eval.featW);
+    }
     return e;
 }
 
@@ -369,8 +665,9 @@ CHESS_API int CHESS_CALL engine_set_option(EngineHandle engine,
 static constexpr int MAX_PLY = 128;            /* ply never exceeds maxDepth (<= 20) */
 
 struct SearchContext {
-    uint64_t    nodes = 0;
-    chess::Move killers[MAX_PLY][2] = {};      /* [ply][slot]; MOVE_NONE until filled */
+    uint64_t          nodes = 0;
+    const EvalParams* eval  = nullptr;         /* eval config for this search; set by engine_best_move */
+    chess::Move       killers[MAX_PLY][2] = {};/* [ply][slot]; MOVE_NONE until filled */
 };
 
 /* Negamax alpha-beta over the shared transposition table. `maxDepth` is the searching
@@ -387,7 +684,7 @@ static int negamax(chess::Position& pos, int maxDepth, int depth, int ply,
         return 0;
 
     if (depth <= 0)
-        return evaluate_stm(pos, whiteToMove);
+        return evaluate_stm(pos, whiteToMove, *ctx.eval);
 
     const uint64_t key  = pos.key();
     TTEntry&       slot = g_tt.entries[key & g_tt.mask];
@@ -502,6 +799,7 @@ CHESS_API int CHESS_CALL engine_best_move(EngineHandle engine,
         return CHESS_ERR_NO_MOVE;
 
     SearchContext ctx;
+    ctx.eval = &engine->eval;
     int maxDepth = depth_for_skill(engine->skill);
     chess::Move bestMove = moves.moves[0];            /* guaranteed-legal fallback */
 
@@ -547,4 +845,135 @@ CHESS_API void CHESS_CALL engine_destroy(EngineHandle engine) {
     delete engine;                                        /* delete nullptr is safe */
 }
 
+/* ---- Learned-weights / training C ABI --------------------------------------------------
+ * The managed side orchestrates games but owns no chess logic: it tells the engine where
+ * to load/save the global weights, records each played position, and applies the result. */
+
+CHESS_API void CHESS_CALL learned_load(const char* path) {
+    std::lock_guard<std::mutex> lock(g_weightsMutex);
+    g_weightsPath = path ? path : "";
+    load_global_weights(path);
+}
+
+CHESS_API int CHESS_CALL weights_snapshot(int* out, int out_len) {
+    const int need = 6 * 64 * 2 + FEATURE_NB;     /* mg + eg (PAWN..KING) + features = 776 */
+    if (!out || out_len < need) return CHESS_ERR_BUFFER;
+
+    std::lock_guard<std::mutex> lock(g_weightsMutex);
+    int n = 0;
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq) out[n++] = g_weights.mg[pt][sq];
+    for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+        for (int sq = 0; sq < 64; ++sq) out[n++] = g_weights.eg[pt][sq];
+    for (int i = 0; i < FEATURE_NB; ++i) out[n++] = g_weights.featW[i];
+    return n;
+}
+
+CHESS_API TrainerHandle CHESS_CALL trainer_create(void) {
+    return new (std::nothrow) Trainer();
+}
+
+CHESS_API void CHESS_CALL trainer_record(TrainerHandle t, const char* fen) {
+    if (!t || !fen || !*fen) return;
+    ensure_initialized();
+
+    chess::Position pos = chess::Position::from_fen(fen);
+    double phase = game_phase(pos);
+
+    /* Per-square occupancy, split into midgame/endgame by phase, white-relative; and the
+     * white-minus-black material balance at this ply, used at trainer_apply time to strip
+     * "material already explains this" out of the training signal. */
+    chess::Bitboard occ = pos.pieces();
+    while (occ) {
+        chess::Square s  = chess::pop_lsb(occ);
+        chess::Piece  pc = pos.piece_on(s);
+        chess::Color  c  = chess::color_of(pc);
+        chess::PieceType pt = chess::type_of(pc);
+        int relSq = (c == chess::WHITE) ? int(s) : (int(s) ^ 56);
+        t->mgOcc[c][pt][relSq] += (1.0 - phase);
+        t->egOcc[c][pt][relSq] += phase;
+        t->matDiffAcc += (c == chess::WHITE ? 1 : -1) * piece_value(pt);
+    }
+
+    /* Per-side feature activations. */
+    double w[FEATURE_NB], b[FEATURE_NB];
+    compute_features(pos, chess::WHITE, phase, w);
+    compute_features(pos, chess::BLACK, phase, b);
+    for (int i = 0; i < FEATURE_NB; ++i) {
+        t->featAcc[chess::WHITE][i] += w[i];
+        t->featAcc[chess::BLACK][i] += b[i];
+    }
+
+    t->plies++;
+}
+
+/* Applies a finished game's outcome as a presence-weighted running average per cell, instead
+ * of an unbounded incremental nudge:
+ *
+ *   score[cell] / visits[cell]  ==  "fraction of (presence-weighted) games won with this piece
+ *                                    on this square, minus fraction lost"
+ *
+ * `weight` is the caller's confidence in the result (1.0 for a checkmate, 0.5 for a
+ * material-imbalance draw, as before). On top of that, the update is scaled by how much of the
+ * result ISN'T already explained by material: `expected` is the win probability the winner's
+ * average material edge over the game implies (the same centipawn->win-probability curve
+ * engines use for Elo estimates); `1 - expected` is the "surprise" left over once material is
+ * accounted for. A win where the winner was already up a rook the whole game is unsurprising
+ * (expected ~= 1, ~no update) — the eval already knows material matters via piece_value(), so
+ * square/feature tables shouldn't get credit for "a piece existed"; a win pulled off (or a draw
+ * held) while materially behind is highly informative and gets a correspondingly large update.
+ * This same magnitude applies to BOTH the winner's reward and the loser's punishment: by the
+ * symmetry of win probabilities (P(loser wins) = 1 - P(winner wins)), the loser's own advantage
+ * — actual(0) minus their expected win probability — has exactly the same magnitude, `1 -
+ * expected`, just negative. */
+CHESS_API void CHESS_CALL trainer_apply(TrainerHandle t, int winner, double weight) {
+    if (!t || t->plies <= 0) return;
+
+    double avgMaterialDiff = t->matDiffAcc / t->plies;                        /* white - black, cp */
+    double winnerMaterialDiff = (winner == chess::WHITE) ? avgMaterialDiff : -avgMaterialDiff;
+    double expected = 1.0 / (1.0 + std::pow(10.0, -winnerMaterialDiff / MATERIAL_ELO_SCALE));
+    double advantageMag = weight * (1.0 - expected);
+
+    std::lock_guard<std::mutex> lock(g_weightsMutex);
+
+    /* pass 0 = winner (positive advantage); pass 1 = loser (negative advantage). */
+    for (int pass = 0; pass < 2; ++pass) {
+        chess::Color side = chess::Color((pass == 0 ? winner : (winner ^ 1)) & 1);
+        double advantage = pass == 0 ? advantageMag : -advantageMag;
+
+        for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
+            for (int sq = 0; sq < 64; ++sq) {
+                double mgFrac = t->mgOcc[side][pt][sq] / t->plies;   /* fraction of the game spent here, [0,1] */
+                if (mgFrac != 0.0) {
+                    g_weights.mgVisits[pt][sq] += mgFrac;
+                    g_weights.mgScore [pt][sq] += mgFrac * advantage;
+                    g_weights.mg[pt][sq] = int(std::lround(
+                        SQ_OUT_SCALE * g_weights.mgScore[pt][sq] / g_weights.mgVisits[pt][sq]));
+                }
+                double egFrac = t->egOcc[side][pt][sq] / t->plies;
+                if (egFrac != 0.0) {
+                    g_weights.egVisits[pt][sq] += egFrac;
+                    g_weights.egScore [pt][sq] += egFrac * advantage;
+                    g_weights.eg[pt][sq] = int(std::lround(
+                        SQ_OUT_SCALE * g_weights.egScore[pt][sq] / g_weights.egVisits[pt][sq]));
+                }
+            }
+
+        for (int i = 0; i < FEATURE_NB; ++i) {
+            double activation = (t->featAcc[side][i] / t->plies) / FEAT_SCALE[i];  /* per-ply average, normalized */
+            if (activation == 0.0) continue;
+            g_weights.featVisits[i] += std::abs(activation);
+            g_weights.featScore [i] += activation * advantage;
+            g_weights.featW[i] = int(std::lround(
+                FEAT_OUT_SCALE * g_weights.featScore[i] / g_weights.featVisits[i]));
+        }
+    }
+
+    save_global_weights();
+}
+
+CHESS_API void CHESS_CALL trainer_destroy(TrainerHandle t) {
+    delete t;                                             /* delete nullptr is safe */
+}
+
 } /* extern "C" */

native/chess_engine/src/position.h

@@ -47,6 +47,22 @@ public:
     void do_move(Move m);
     void undo_move(Move m);
 
+    // Legal moves for a SPECIFIED color (for mobility eval of either side). When c is not
+    // the side to move, temporarily flips side-to-move (and clears the en-passant square,
+    // which belongs to the other side) so generate_legal runs for c, then restores. The
+    // Zobrist key is untouched and unused by move generation, so this leaves the position
+    // observably unchanged.
+    void generate_legal_for(Color c, MoveList& list) {
+        if (sideToMove == c) { generate_legal(list); return; }
+        Color  savedSide = sideToMove;
+        Square savedEp    = epSquare;
+        sideToMove = c;
+        epSquare   = SQ_NONE;
+        generate_legal(list);
+        sideToMove = savedSide;
+        epSquare   = savedEp;
+    }
+
     // Seed prior-position keys (oldest first, excluding the current position) so
     // is_draw() can see game history the FEN doesn't carry. Call once, right after
     // from_fen and before any do_move.

tests/holdem/README.md

@@ -0,0 +1,83 @@
+# Hold'em dealer tests
+
+Unit tests for the money logic behind `/Casino/TexasHoldem` — the betting engine, the
+side-pot calculator, the split calculator and the table state.
+
+```bash
+node --test tests/holdem/*.test.js
+```
+
+No install step, no `package.json`, no dependencies. The browser modules are plain
+script-tag files that each end with a `module.exports` guard, so Node can require them
+as-is; `load.js` puts them on `globalThis` under the same names they use to find each
+other in the page, in the load order from `TexasHoldem.cshtml`.
+
+## What's covered
+
+| File | Covers |
+| --- | --- |
+| `potCalculator.test.js` | Main and side pots, dead money, uncalled bets, odd-cent distribution |
+| `betting.test.js` | Blinds, street completion, raises reopening the action, all-in run-outs |
+| `state.test.js` | Button rotation, which seats post blinds, session standings |
+| `splitCalculator.test.js` | Chopped pots, odd chips, unmakeable denominations |
+| `invariants.test.js` | 1000 randomised hands per property (see below) |
+
+## The layout audit
+
+The unit tests above cover the money. `uiAudit.js` covers the thing you can only see
+in a browser: whether a dealer can actually reach every control.
+
+```bash
+node tests/holdem/runUiAudit.js          # needs Playwright and the site running
+```
+
+It checks WCAG AA contrast, touch target sizes, touch-action and tap highlights, that fields stay selectable and are large
+enough not to trigger iOS zoom, that nothing important is covered or off-screen with
+no way to scroll to it, that no grid column has collapsed to nothing, and that no
+text is painted outside its box. It runs over the table, all five overlays and Quick
+Split, at thirteen viewports from a 360px phone to a 1600px desktop and the same
+phones on their side.
+
+Deliberately not in CI: the unit suite is dependency-free and runs in a second, while
+this one needs a browser and a running site. Run it after any change that adds or
+resizes a control. With no Playwright to hand, paste `uiAudit.js` into devtools and
+call `LayoutAudit.runAll()`.
+
+The contrast check is built so it cannot report a false positive: backgrounds
+composite through alpha, and where a gradient is involved every colour stop is tried
+and the most flattering one used. A finding means the text fails even under the
+reading most generous to it. Two earlier attempts at this got it wrong in both
+directions — one read only `background-color` and scored text on a gradient against
+nothing, the other treated low-alpha stops as opaque — so `uiAudit.js` is checked
+against known-answer cases before it is believed.
+
+Touch targets are measured by probing outward with `elementFromPoint` rather than by
+reading the element box, because the box lies in both directions: a small control can
+be padded out with a transparent `::after` and respond well beyond its painted size,
+and a checkbox inside a label is hit by tapping the label. The 44px rule is only
+enforced where `hover: none` says there's no mouse.
+
+It exists because these checks were being re-typed into a console every time
+something changed, and each time they only covered whatever had just been touched.
+That is how the standings table shipped with a player-name column zero pixels wide
+and kept it for two rounds.
+
+## Why the randomised suite exists
+
+Every correctness bug found in this tool so far has been shape-dependent: blinds posted
+to empty chairs, the button skipping past players, heads-up acting out of order, an
+overbet announced as a side pot. None of them show up on a full six-handed table with
+equal stacks, which is the table anyone writes a fixed example for.
+
+`invariants.test.js` deals a thousand hands across random seat counts, random empty
+chairs, random stack depths and random dealer input, and checks the things a dealer
+would notice being wrong:
+
+- chips are never created or destroyed during play
+- the pot breakdown plus the uncalled returns always equal the money that went in
+- paying the pot out settles it to the cent
+- once uncalled chips are handed back, nobody is still betting above the whole table
+- the button and both blinds always land on players who are actually in the hand
+
+The generator is seeded, so a failure reproduces from the seed printed in the message
+rather than being a flake to re-run.

tests/holdem/allInMarker.test.js

@@ -0,0 +1,98 @@
+// Who the felt marks "ALL IN".
+//
+// The mark's whole value is that a dealer can scan the ring and see who can still be
+// bet at, so the test that matters most is the last one: the seats it marks are
+// exactly the seats the betting round refuses to ask for another chip.
+const test = require("node:test");
+const assert = require("node:assert");
+const { Betting, HoldemState, makeTable, chipsOnTable } = require("./load");
+
+test("a player who moved all-in is marked", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100 });
+    state.seats[3].stack = 12;
+    Betting.beginHand(state);
+    Betting.allIn(state, state.actingSeatIndex);
+
+    assert.equal(Betting.isAllIn(state, state.seats[3]), true);
+    assert.equal(state.seats[3].stack, 0);
+});
+
+test("a player with chips behind is not", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    Betting.beginHand(state);
+    assert.equal(Betting.isAllIn(state, state.seats[0]), false);
+    assert.equal(Betting.isAllIn(state, state.seats[1]), false);
+});
+
+test("a busted player who was dealt in but has put nothing in is not", () => {
+    // An empty stack alone isn't all-in — it's someone who shouldn't have been dealt
+    // in. Calling that "ALL IN" on the felt would be a lie about a live pot.
+    const state = makeTable({ seatCount: 4, seated: [0, 1, 2], stack: 100 });
+    state.seats[2].stack = 0;
+    assert.equal(Betting.isAllIn(state, state.seats[2]), false);
+});
+
+test("a folded player with an empty stack is not", () => {
+    const state = makeTable({ seatCount: 4, seated: [0, 1, 2], stack: 100 });
+    state.seats[1].committed = 5;
+    state.seats[1].stack = 0;
+    state.seats[1].folded = true;
+    assert.equal(Betting.isAllIn(state, state.seats[1]), false);
+});
+
+test("an empty chair is not", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1], stack: 100 });
+    assert.equal(Betting.isAllIn(state, state.seats[4]), false);
+});
+
+test("a seat with no stack of its own falls back to the table's and isn't marked", () => {
+    const state = makeTable({ seatCount: 4, seated: [0, 1, 2], stack: 100 });
+    state.defaultStack = 200;
+    state.seats[2].stack = null;
+    state.seats[2].committed = 10;
+    assert.equal(Betting.isAllIn(state, state.seats[2]), false);
+});
+
+test("the seats marked are exactly the ones the action passes over", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100 });
+    state.seats[1].stack = 8;
+    state.seats[3].stack = 30;
+    Betting.beginHand(state);
+
+    // Everyone in, two of them for less than the others can cover.
+    for (let step = 0; step < 4; step++) Betting.allIn(state, state.actingSeatIndex);
+
+    const marked = state.seats
+        .map((player, index) => (Betting.isAllIn(state, player) ? index : null))
+        .filter(index => index !== null);
+    const skipped = state.seats
+        .map((player, index) =>
+            player.inHand && !player.folded && Betting.nextToAct(state, index - 1) !== index ? index : null)
+        .filter(index => index !== null);
+
+    assert.deepEqual(marked, skipped);
+    assert.ok(marked.length > 0, "the scenario should actually produce all-in players");
+});
+
+test("nobody is marked once the next hand starts", () => {
+    const state = makeTable({ seatCount: 4, seated: [0, 1, 2], stack: 100 });
+    state.seats[2].stack = 5;
+    Betting.beginHand(state);
+    Betting.allIn(state, state.actingSeatIndex);
+    assert.ok(state.seats.some(player => Betting.isAllIn(state, player)));
+
+    // The short stack got there by winning nothing; give them chips back the way a
+    // dealer would before the next deal.
+    HoldemState.startNextHand(state);
+    state.seats[2].stack = 50;
+    assert.equal(state.seats.filter(player => Betting.isAllIn(state, player)).length, 0);
+});
+
+test("marking nobody doesn't move a chip", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100 });
+    state.seats[3].stack = 12;
+    Betting.beginHand(state);
+    const before = chipsOnTable(state);
+    state.seats.forEach(player => Betting.isAllIn(state, player));
+    assert.equal(chipsOnTable(state), before);
+});

tests/holdem/bankAudit.test.js

@@ -0,0 +1,169 @@
+// The banker's job, which is a different job from the dealer's: every chip on the
+// table is a promise to pay cash for it later, and somebody has to be able to check
+// that the promise can be kept before the last two players try to cash out.
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { Betting, HoldemState, Money, makeTable } = require("./load");
+
+const seat = (state, index, name, cash, chips) => {
+    const p = state.seats[index];
+    p.name = name; p.inHand = true; p.buyIns = cash; p.stack = chips;
+    return p;
+};
+
+describe("everyone with money in the game is accounted for", () => {
+    test("a player who has bought in but played no logged hand still appears", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 0 });
+        seat(state, 0, "Ann", 100, 100);
+        seat(state, 1, "Ben", 100, 100);
+        seat(state, 2, "Cal", 200, 200); // just sat down
+
+        state.seats[0].amountOverride = 10;
+        state.seats[1].amountOverride = 10;
+        HoldemState.recordHand(state, [{ id: state.seats[0].id, label: "Ann", amount: 20 }]);
+        state.seats[0].amountOverride = null;
+        state.seats[1].amountOverride = null;
+
+        const names = HoldemState.sessionStandings(state).map(r => r.name);
+        assert.ok(names.includes("Cal"), `Cal handed over $200 and is missing: ${names.join(", ")}`);
+    });
+
+    test("their row reads as no hands played, not as a loss", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1], stack: 0 });
+        seat(state, 0, "Ann", 100, 100);
+        seat(state, 1, "Ben", 200, 200);
+
+        const cal = HoldemState.sessionStandings(state).find(r => r.name === "Ben");
+        assert.equal(cal.in, 0);
+        assert.equal(cal.won, 0);
+        assert.equal(cal.net, 0);
+        assert.equal(cal.boughtIn, 200);
+        assert.equal(cal.cashPosition, 0, "level: they've bought chips and still hold them");
+    });
+
+    test("an empty chair is not dragged into the settle-up", () => {
+        const state = makeTable({ seatCount: 9, seated: [0], stack: 0 });
+        seat(state, 0, "Ann", 100, 100);
+        const rows = HoldemState.sessionStandings(state);
+        assert.equal(rows.length, 1);
+    });
+
+    test("somebody who has cashed out completely still shows what they took", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1], stack: 0 });
+        seat(state, 0, "Ann", 100, 0);   // handed every chip back
+        seat(state, 1, "Ben", 100, 200);
+        const ann = HoldemState.sessionStandings(state).find(r => r.name === "Ann");
+        assert.equal(ann.cashPosition, -100, "down the whole buy-in");
+    });
+});
+
+describe("does the cash box cover the chips on the table", () => {
+    test("a straight game balances", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2], stack: 0 });
+        seat(state, 0, "Ann", 100, 60);
+        seat(state, 1, "Ben", 100, 140);
+        seat(state, 2, "Cal", 100, 100);
+
+        const bank = HoldemState.bankReconciliation(state);
+        assert.equal(bank.cashIn, 300);
+        assert.equal(bank.chipsInPlay, 300);
+        assert.equal(bank.difference, 0);
+        assert.equal(bank.balanced, true);
+    });
+
+    test("chips outrunning the cash box is caught before cash-out", () => {
+        // The 2am failure: the last players out can't be paid.
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2], stack: 0 });
+        seat(state, 0, "Ann", 100, 100);
+        seat(state, 1, "Ben", 100, 100);
+        seat(state, 2, "Cal", 100, 260); // took chips for a rebuy nobody wrote down
+
+        const bank = HoldemState.bankReconciliation(state);
+        assert.equal(bank.cashIn, 300);
+        assert.equal(bank.chipsInPlay, 460);
+        assert.equal(bank.difference, 160);
+        assert.equal(bank.balanced, false);
+    });
+
+    test("cash taken for chips never handed over is caught too", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1], stack: 0 });
+        seat(state, 0, "Ann", 200, 100); // paid 200, only got 100 in chips
+        seat(state, 1, "Ben", 100, 100);
+
+        const bank = HoldemState.bankReconciliation(state);
+        assert.equal(bank.difference, -100);
+        assert.equal(bank.balanced, false);
+    });
+
+    test("chips in the middle still count as chips in play", () => {
+        // Money in the pot is somebody's; it just hasn't been won yet. Leaving it out
+        // would report a shortfall every time a hand was open — which is nearly always.
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        state.seats.forEach(p => { if (p.inHand) p.buyIns = 100; });
+
+        const before = HoldemState.bankReconciliation(state);
+        assert.equal(before.balanced, true);
+
+        Betting.beginHand(state);              // blinds go in
+        Betting.raiseTo(state, 0, 25);         // and a raise
+        Betting.sweepToHandTotals(state);      // banked into the pot
+
+        const during = HoldemState.bankReconciliation(state);
+        assert.equal(during.balanced, true, "an open pot is not a discrepancy");
+        assert.equal(during.chipsInPlay, before.chipsInPlay);
+    });
+
+    test("a whole session of play never knocks the books out", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        state.seats.forEach(p => { if (p.inHand) p.buyIns = 100; });
+
+        for (let hand = 0; hand < 6; hand++) {
+            Betting.beginHand(state);
+            Betting.liveSeats(state).forEach(s => {
+                if (Betting.toCall(state, s.player) > 0) Betting.call(state, s.index);
+            });
+            Betting.sweepToHandTotals(state);
+
+            const pot = HoldemState.totalPot(state);
+            const winner = Betting.liveSeats(state)[0];
+            const payouts = [{ id: winner.player.id, label: "w", amount: pot }];
+            HoldemState.recordHand(state, payouts);
+            Betting.creditWinnings(state, payouts);
+            HoldemState.startNextHand(state);
+
+            assert.equal(HoldemState.bankReconciliation(state).balanced, true, `books off after hand ${hand + 1}`);
+        }
+    });
+
+    test("a rebuy keeps the books straight, a chip grab doesn't", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1], stack: 0 });
+        seat(state, 0, "Ann", 100, 100);
+        seat(state, 1, "Ben", 100, 100);
+
+        // A proper rebuy: cash to the banker, chips to the player.
+        state.seats[0].buyIns += 100;
+        state.seats[0].stack += 100;
+        assert.equal(HoldemState.bankReconciliation(state).balanced, true);
+
+        // Chips taken without paying.
+        state.seats[1].stack += 50;
+        const bank = HoldemState.bankReconciliation(state);
+        assert.equal(bank.balanced, false);
+        assert.equal(bank.difference, 50);
+    });
+
+    test("nothing to reconcile before anybody has bought in", () => {
+        const state = makeTable({ seatCount: 6, seated: [], stack: 0 });
+        const bank = HoldemState.bankReconciliation(state);
+        assert.equal(bank.cashIn, 0);
+        assert.equal(bank.chipsInPlay, 0);
+        assert.equal(bank.balanced, true);
+    });
+
+    test("float dust is not a discrepancy", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1], stack: 0 });
+        seat(state, 0, "Ann", 0.1 + 0.2, 0.3);
+        seat(state, 1, "Ben", 10, 10);
+        assert.equal(HoldemState.bankReconciliation(state).balanced, true);
+    });
+});

tests/holdem/betting.test.js

@@ -0,0 +1,198 @@
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { Betting, makeTable, chipsOnTable } = require("./load");
+
+describe("Betting.beginHand", () => {
+    test("blinds are posted and the seat after the big blind acts first", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 0, smallBlind: 1, bigBlind: 2 });
+        Betting.beginHand(state);
+
+        assert.equal(state.seats[1].committed, 1, "small blind");
+        assert.equal(state.seats[2].committed, 2, "big blind");
+        assert.equal(state.currentBet, 2);
+        assert.equal(state.actingSeatIndex, 3, "under the gun");
+    });
+
+    test("heads-up, the button posts the small blind and acts first pre-flop", () => {
+        const state = makeTable({ seatCount: 6, seated: [2, 5], dealerSeatIndex: 2 });
+        Betting.beginHand(state);
+
+        assert.equal(state.seats[2].committed, 1, "the button is the small blind");
+        assert.equal(state.seats[5].committed, 2);
+        assert.equal(state.actingSeatIndex, 2, "the small blind acts first pre-flop heads-up");
+    });
+
+    test("heads-up, the big blind acts first once the flop is out", () => {
+        const state = makeTable({ seatCount: 6, seated: [2, 5], dealerSeatIndex: 2 });
+        Betting.beginHand(state);
+        Betting.call(state, 2);
+        Betting.check(state, 5);
+        Betting.closeStreet(state);
+
+        assert.equal(state.street, "flop");
+        assert.equal(state.actingSeatIndex, 5, "the big blind is first to act after the flop");
+    });
+
+    test("a blind bigger than a stack puts that player all-in without stalling the action", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1], dealerSeatIndex: 0, smallBlind: 50, bigBlind: 100 });
+        state.seats[0].stack = 10; // can't cover the small blind
+
+        Betting.beginHand(state);
+        assert.equal(state.seats[0].stack, 0, "all-in for what they had");
+        assert.equal(state.seats[0].committed, 10);
+        assert.notEqual(state.actingSeatIndex, 0, "a player with no chips has nothing to decide");
+    });
+
+    test("posting blinds never invents or destroys chips", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100 });
+        const before = chipsOnTable(state);
+        Betting.beginHand(state);
+        assert.equal(chipsOnTable(state), before);
+    });
+});
+
+describe("Betting street completion", () => {
+    test("a street ends once everyone has matched the bet and had a turn", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+
+        Betting.call(state, 3);
+        Betting.call(state, 0);
+        Betting.call(state, 1);
+        assert.equal(Betting.isStreetComplete(state), false, "the big blind still has an option");
+
+        Betting.check(state, 2);
+        assert.equal(Betting.isStreetComplete(state), true);
+        assert.equal(state.actingSeatIndex, null);
+    });
+
+    test("a raise reopens the action for everyone who had already called", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+
+        Betting.call(state, 3);
+        Betting.call(state, 0);
+        assert.equal(state.seats[3].hasActed, true);
+
+        Betting.raiseTo(state, 1, 10);
+        assert.equal(state.seats[3].hasActed, false, "seat 3 owes a response again");
+        assert.equal(state.seats[0].hasActed, false);
+        assert.equal(state.currentBet, 10);
+        assert.equal(Betting.isStreetComplete(state), false);
+    });
+
+    test("the action skips a player who is all-in but still in the hand", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        state.seats[3].stack = 5;
+        Betting.beginHand(state);
+
+        Betting.allIn(state, 3);
+        assert.equal(state.seats[3].stack, 0);
+        assert.notEqual(state.actingSeatIndex, 3);
+        // They are still live and can still win the pot.
+        assert.ok(Betting.liveSeats(state).some(s => s.index === 3));
+    });
+
+    test("closing a street sweeps chips into hand totals and resets the bet", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.call(state, 3);
+        Betting.call(state, 0);
+        Betting.call(state, 1);
+        Betting.check(state, 2);
+
+        const before = chipsOnTable(state);
+        Betting.closeStreet(state);
+
+        assert.equal(state.currentBet, 0);
+        assert.equal(state.street, "flop");
+        assert.equal(chipsOnTable(state), before, "sweeping moves chips, it doesn't change the total");
+        state.seats.forEach(p => assert.equal(p.committed, 0));
+        assert.equal(Betting.handTotal(state.seats[2]), 2);
+    });
+});
+
+describe("Betting all-in run-outs", () => {
+    test("with everyone all-in there is nobody left to ask", () => {
+        const state = makeTable({ seatCount: 3, seated: [0, 1, 2], stack: 20, dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.allIn(state, 2);
+        Betting.allIn(state, 0);
+        Betting.allIn(state, 1);
+
+        assert.equal(Betting.canStillBet(state), false);
+        assert.equal(Betting.isRunningOut(state), true, "the board just gets dealt out");
+
+        Betting.closeStreet(state);
+        assert.equal(state.actingSeatIndex, null, "no phantom action on the flop");
+    });
+
+    test("one player with chips against an all-in cannot bet alone", () => {
+        const state = makeTable({ seatCount: 3, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        state.seats[1].stack = 5;
+        Betting.beginHand(state);
+        Betting.fold(state, 2);
+        Betting.allIn(state, 0);
+        Betting.allIn(state, 1);
+
+        assert.equal(Betting.canStillBet(state), false);
+        assert.equal(Betting.isHandOver(state), false, "two players are still live for the showdown");
+    });
+
+    test("everyone folding to one player ends the hand", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.fold(state, 3);
+        Betting.fold(state, 0);
+        Betting.fold(state, 1);
+
+        assert.equal(Betting.isHandOver(state), true);
+    });
+});
+
+describe("Betting money handling", () => {
+    test("a player can never put in more than they have", () => {
+        const state = makeTable({ seatCount: 3, seated: [0, 1, 2], stack: 30, dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        const moved = Betting.putIn(state, 0, 500);
+        assert.equal(moved, 30);
+        assert.equal(state.seats[0].stack, 0);
+    });
+
+    test("raise-to is what a dealer says out loud, not raise-by", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.raiseTo(state, 3, 10);
+        assert.equal(state.seats[3].committed, 10, "their street total is 10, not 10 on top");
+        assert.equal(state.seats[3].stack, 90);
+    });
+
+    test("the minimum raise has to match the last one", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        assert.equal(Betting.minRaiseTo(state), 4, "a big blind of 2 makes the first raise 4");
+
+        Betting.raiseTo(state, 3, 10);
+        assert.equal(Betting.minRaiseTo(state), 18, "an 8-chip raise means the next one is to 18");
+    });
+
+    test("winnings land back in front of the player", () => {
+        const state = makeTable({ seatCount: 3, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.creditWinnings(state, [{ id: state.seats[0].id, amount: 42.5 }]);
+        assert.equal(state.seats[0].stack, 142.5, "the button posts nothing three-handed");
+    });
+
+    test("fractional blinds don't drift into floating-point dust", () => {
+        const state = makeTable({ seatCount: 3, seated: [0, 1, 2], stack: 10, smallBlind: 0.1, bigBlind: 0.2 });
+        Betting.beginHand(state);
+        Betting.call(state, 0); // button limps
+        Betting.call(state, 1); // small blind completes
+        Betting.check(state, 2); // big blind is happy
+        Betting.closeStreet(state);
+
+        assert.equal(chipsOnTable(state), 30, "0.1 + 0.2 arithmetic didn't lose a chip");
+        assert.equal(Betting.potSoFar(state), 0.6);
+        state.seats.forEach(p => assert.equal(p.stack, 9.8));
+    });
+});

tests/holdem/brokeSeats.test.js

@@ -0,0 +1,148 @@
+// Dealing around a player who busted and hasn't bought back in.
+//
+// A home game produces one of these about once an hour. The table used to deal them
+// in anyway, promise a blind from a seat with nothing to post it with, take it from
+// nobody, and then sit on a hand that could never finish.
+const test = require("node:test");
+const assert = require("node:assert");
+const { Betting, HoldemState, makeTable, chipsOnTable } = require("./load");
+
+const postedBy = state =>
+    state.seats
+        .map((player, index) => (player.committed > 0 ? { seat: index + 1, amount: player.committed } : null))
+        .filter(Boolean);
+
+test("a seat with no chips and nothing in the pot is broke", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.seats[2].stack = 0;
+    assert.deepEqual(Betting.brokeSeats(state), [2]);
+});
+
+test("an all-in player is not broke — they have money riding on the hand", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.seats[2].stack = 12;
+    Betting.beginHand(state);
+    Betting.allIn(state, 2);
+
+    assert.equal(Betting.stackOf(state, state.seats[2]), 0);
+    assert.equal(Betting.isAllIn(state, state.seats[2]), true);
+    assert.deepEqual(Betting.brokeSeats(state), []);
+});
+
+test("a seat with no stack recorded falls back to the table's and isn't broke", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.defaultStack = 200;
+    state.seats[2].stack = null;
+    assert.deepEqual(Betting.brokeSeats(state), []);
+});
+
+test("a chair nobody is sitting in isn't broke, it's empty", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    assert.deepEqual(Betting.brokeSeats(state), []);
+});
+
+test("dealing sits the broke seat out and leaves everything else about it alone", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100 });
+    state.seats[2].stack = 0;
+    state.seats[2].name = "Cal";
+    state.seats[2].buyIns = 100;
+
+    Betting.beginHand(state);
+
+    assert.equal(state.seats[2].inHand, false);
+    assert.equal(state.seats[2].folded, false, "sat out, not folded — they didn't muck anything");
+    assert.equal(state.seats[2].name, "Cal");
+    assert.equal(state.seats[2].buyIns, 100);
+});
+
+test("the blinds skip the broke seat and land on players who can post", () => {
+    // Button on seat 1, so the blinds would be seats 2 and 3. Seat 2 is busted.
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100, dealerSeatIndex: 0 });
+    state.seats[1].stack = 0;
+
+    Betting.beginHand(state);
+
+    assert.deepEqual(postedBy(state), [
+        { seat: 3, amount: state.smallBlind },
+        { seat: 4, amount: state.bigBlind },
+    ]);
+});
+
+test("the preview promises what the deal produces", () => {
+    // The fault this whole step exists to prevent: the preview once read a table the
+    // deal was about to change underneath it.
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100, dealerSeatIndex: 0 });
+    state.seats[1].stack = 0;
+    state.bettingOpen = false;
+
+    const preview = Betting.blindPreview(state);
+    assert.deepEqual(preview.satOut, [1]);
+
+    Betting.beginHand(state);
+    const posted = postedBy(state);
+    assert.equal(posted.find(p => p.amount === state.smallBlind).seat, preview.sbIndex + 1);
+    assert.equal(posted.find(p => p.amount === state.bigBlind).seat, preview.bbIndex + 1);
+});
+
+test("asking for the preview doesn't sit anybody out on its own", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.seats[1].stack = 0;
+
+    Betting.blindPreview(state);
+
+    assert.equal(state.seats[1].inHand, true, "the preview is a view, not a change");
+});
+
+test("with only one player left holding chips there is nothing to preview", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.seats[1].stack = 0;
+    state.seats[2].stack = 0;
+
+    assert.equal(Betting.blindPreview(state), null);
+});
+
+test("no chips move when the broke seats are dealt around", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100 });
+    state.seats[2].stack = 0;
+    const before = chipsOnTable(state);
+
+    Betting.beginHand(state);
+
+    assert.equal(chipsOnTable(state), before);
+});
+
+test("the board isn't running out before the hand is dealt", () => {
+    // Two busted players and one with chips looks exactly like a table of all-ins to
+    // the run-out test, and the bar was announcing one over an empty felt.
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.seats[1].stack = 0;
+    state.seats[2].stack = 0;
+    state.bettingOpen = false;
+
+    assert.equal(Betting.isRunningOut(state), false);
+});
+
+test("buying back in puts them in the next hand", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.seats[2].stack = 0;
+    Betting.beginHand(state);
+    assert.equal(state.seats[2].inHand, false);
+
+    // What the dealer does when they hand over cash: chips, and back in.
+    state.seats[2].stack = 100;
+    state.seats[2].inHand = true;
+    HoldemState.startNextHand(state);
+    Betting.beginHand(state);
+
+    assert.equal(state.seats[2].inHand, true);
+    assert.equal(Betting.liveSeats(state).length, 3);
+});
+
+test("the table dealt around them counts the right number of players", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100 });
+    state.seats[3].stack = 0;
+
+    assert.equal(Betting.liveSeats(state).length, 4);
+    assert.equal(Betting.liveSeats(Betting.tableAsDealt(state)).length, 3);
+    assert.equal(state.seats[3].inHand, true, "the view didn't touch the table");
+});

tests/holdem/buyIn.test.js

@@ -0,0 +1,76 @@
+// Whether handing a seat chips also puts them back in the game.
+const test = require("node:test");
+const assert = require("node:assert");
+const { Betting, makeTable } = require("./load");
+
+test("a busted player who has been sat out comes back in", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.seats[1].stack = 0;
+    Betting.beginHand(state);           // the deal sits them out
+
+    assert.equal(state.seats[1].inHand, false);
+    assert.equal(Betting.buyInDealsThemIn(state.seats[1]), true);
+});
+
+test("a chair being bought into for the first time comes in", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1], stack: 100 });
+    state.seats[4].name = "Eve";
+    state.seats[4].stack = null;
+
+    assert.equal(Betting.buyInDealsThemIn(state.seats[4]), true);
+});
+
+test("a seat sat out while holding chips stays out", () => {
+    // A dealer sat them out on purpose and is topping them up. Dealing them back in
+    // would be the tool guessing at something it wasn't told.
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.seats[2].inHand = false;
+
+    assert.equal(Betting.buyInDealsThemIn(state.seats[2]), false);
+});
+
+test("somebody already in the hand is left exactly where they are", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    assert.equal(Betting.buyInDealsThemIn(state.seats[0]), false);
+
+    // Including a player who is in but out of chips — they're all-in, not sat out.
+    state.seats[2].stack = 0;
+    assert.equal(state.seats[2].inHand, true);
+    assert.equal(Betting.buyInDealsThemIn(state.seats[2]), false);
+});
+
+test("a blank stack field reads as nothing recorded, not as a number", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1], stack: 100 });
+    state.seats[3].name = "Dee";
+    state.seats[3].stack = "";
+
+    assert.equal(Betting.buyInDealsThemIn(state.seats[3]), true);
+});
+
+test("it doesn't ask the table what a missing stack would have been", () => {
+    // stackOf substitutes the table's starting stack for a seat that has none, which
+    // would make a seat with nothing recorded look like it was holding chips.
+    const state = makeTable({ seatCount: 6, seated: [0, 1], stack: 100 });
+    state.defaultStack = 500;
+    state.seats[4].name = "Eve";
+    state.seats[4].stack = null;
+
+    assert.equal(Betting.stackOf(state, state.seats[4]), 500);
+    assert.equal(Betting.buyInDealsThemIn(state.seats[4]), true);
+});
+
+test("asking doesn't change anything", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.seats[2].stack = 0;
+    state.seats[2].inHand = false;
+    const before = JSON.stringify(state);
+
+    Betting.buyInDealsThemIn(state.seats[2]);
+
+    assert.equal(JSON.stringify(state), before);
+});
+
+test("nothing to decide about a seat that isn't there", () => {
+    assert.equal(Betting.buyInDealsThemIn(null), false);
+    assert.equal(Betting.buyInDealsThemIn(undefined), false);
+});

tests/holdem/chipBreakdown.test.js

@@ -0,0 +1,82 @@
+// The chips to actually push, for an amount.
+const test = require("node:test");
+const assert = require("node:assert");
+const { Money } = require("./load");
+
+// A standard house set.
+const LEGEND = [
+    { value: 1, color: "#fff" },
+    { value: 5, color: "#c0392b" },
+    { value: 25, color: "#27ae60" },
+    { value: 100, color: "#2c3e50" },
+    { value: 500, color: "#8e44ad" },
+];
+
+const say = (amount, legend = LEGEND) => Money.formatChipBreakdown(amount, legend);
+
+test("a payout comes back as chips, largest first", () => {
+    assert.equal(say(132), "1×$100, 1×$25, 1×$5, 2×$1");
+});
+
+test("it uses the fewest chips on a normal set", () => {
+    const { chips } = Money.chipBreakdown(500, LEGEND);
+    assert.deepEqual(chips.map(c => `${c.count}×${c.value}`), ["1×500"]);
+});
+
+test("a denomination that doesn't fit is skipped rather than listed as none", () => {
+    assert.equal(say(7), "1×$5, 2×$1");
+});
+
+test("nothing to pay is nothing to say", () => {
+    assert.equal(say(0), "");
+    assert.equal(say(-5), "");
+});
+
+test("no legend means no advice, not a wrong answer", () => {
+    // A table that never set chip colours up gets the amount on its own.
+    assert.equal(say(132, []), "");
+    assert.equal(say(132, null), "");
+});
+
+test("a legend with no values in it yet is the same as none", () => {
+    assert.equal(say(132, [{ value: "", color: "#fff" }, { value: 0, color: "#000" }]), "");
+});
+
+test("what the smallest chip can't make is reported, not rounded away", () => {
+    // 50c in a game whose smallest chip is a dollar is the dealer's problem to solve,
+    // and they can only solve it if they're told.
+    const { chips, remainder } = Money.chipBreakdown(10.5, LEGEND);
+    assert.deepEqual(chips.map(c => `${c.count}×${c.value}`), ["2×5"]);
+    assert.equal(remainder, 0.5);
+    assert.equal(say(10.5), "2×$5, $0.50 no chip covers");
+});
+
+test("cent chips make cent amounts exactly", () => {
+    const cents = [{ value: 0.25 }, { value: 0.05 }, { value: 0.01 }];
+    assert.equal(say(0.41, cents), "1×$0.25, 3×$0.05, 1×$0.01");
+    assert.equal(Money.chipBreakdown(0.41, cents).remainder, 0);
+});
+
+test("the chips add up to the amount", () => {
+    for (const amount of [1, 7, 33, 132, 499, 500, 1234, 9999]) {
+        const { chips, remainder } = Money.chipBreakdown(amount, LEGEND);
+        const total = chips.reduce((sum, c) => sum + c.count * c.value, 0) + remainder;
+        assert.equal(Money.round(total), amount, `${amount} should be accounted for`);
+    }
+});
+
+test("a legend in any order still pays largest first", () => {
+    const jumbled = [{ value: 25 }, { value: 1 }, { value: 500 }, { value: 5 }, { value: 100 }];
+    assert.equal(say(631, jumbled), "1×$500, 1×$100, 1×$25, 1×$5, 1×$1");
+});
+
+test("the colour comes along, so the felt can say it in chips", () => {
+    const { chips } = Money.chipBreakdown(25, LEGEND);
+    assert.equal(chips[0].color, "#27ae60");
+});
+
+test("a legend that exists but can't reach the amount does say so", () => {
+    // Different from having no legend at all: this table has told us its chips, and
+    // the answer is that they don't go that low.
+    assert.equal(say(3, [{ value: 5 }, { value: 25 }]), "$3 no chip covers");
+});

tests/holdem/dealStep.test.js

@@ -0,0 +1,205 @@
+// Dealing and betting are two decisions, and fusing them meant the table guessed.
+//
+// The moment between hands is when people sit down, stand up and argue about whose
+// turn it is. With blinds posted the instant the previous hand ended, the blind
+// badges recomputed off `inHand` while the committed chips stayed frozen — so seating
+// somebody produced a big blind who had posted nothing.
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { Betting, HoldemState, makeTable, chipsOnTable } = require("./load");
+
+const postedBy = state => state.seats
+    .map((p, i) => (Betting.committed(p) > 0 ? i : null))
+    .filter(i => i !== null);
+
+describe("the table waits to be dealt", () => {
+    test("finishing a hand leaves the next one un-dealt", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        assert.equal(state.bettingOpen, true);
+
+        HoldemState.startNextHand(state);
+
+        assert.equal(state.bettingOpen, false, "the next hand hasn't been dealt");
+        assert.equal(state.actingSeatIndex, null, "nobody is on the clock");
+        assert.deepEqual(postedBy(state), [], "and no blind has been committed");
+    });
+
+    test("no money moves until the dealer deals", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        const start = chipsOnTable(state);
+        HoldemState.startNextHand(state);
+
+        assert.equal(chipsOnTable(state), start);
+        assert.equal(HoldemState.totalPot(state), 0);
+
+        Betting.beginHand(state);
+        assert.equal(state.bettingOpen, true);
+        assert.equal(postedBy(state).length, 2, "now the blinds are in");
+        assert.equal(chipsOnTable(state), start, "and nothing was created doing it");
+    });
+});
+
+describe("setting the table costs nothing", () => {
+    test("seating a player before the deal changes who posts", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        HoldemState.startNextHand(state);
+
+        const before = Betting.blindPreview(state);
+        state.seats[3].inHand = true;
+        state.seats[3].stack = 100;
+        const after = Betting.blindPreview(state);
+
+        assert.notDeepEqual(
+            [before.sbIndex, before.bbIndex],
+            [after.sbIndex, after.bbIndex],
+            "the preview follows the new table"
+        );
+        assert.deepEqual(postedBy(state), [], "and still nothing is committed");
+
+        Betting.beginHand(state);
+        assert.deepEqual(postedBy(state).sort(), [after.sbIndex, after.bbIndex].sort(),
+            "the money lands where the preview said it would");
+    });
+
+    test("removing a player before the deal can't strand their blind", () => {
+        // The old failure: take out the big blind after the hand had begun and their
+        // chips stayed in the pot while the badge moved to somebody who'd posted
+        // nothing. Before the deal there is nothing to strand.
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        HoldemState.startNextHand(state);
+
+        const doomed = Betting.blindPreview(state).bbIndex;
+        state.seats[doomed].inHand = false;
+
+        assert.deepEqual(postedBy(state), [], "nobody has posted, so nothing is stranded");
+
+        Betting.beginHand(state);
+        const posted = postedBy(state);
+        assert.ok(!posted.includes(doomed), "the player who left posts nothing");
+        posted.forEach(i => assert.ok(state.seats[i].inHand, "only players in the hand post"));
+    });
+
+    test("moving the button before the deal just moves it", () => {
+        const state = makeTable({ seatCount: 8, seated: [0, 2, 4, 6], dealerSeatIndex: 0 });
+        const start = chipsOnTable(state);
+        HoldemState.startNextHand(state);
+
+        [2, 4, 6, 0].forEach(seat => {
+            state.dealerSeatIndex = seat;
+            assert.deepEqual(postedBy(state), [], `passing the button to seat ${seat + 1} posted something`);
+            assert.equal(chipsOnTable(state), start);
+        });
+
+        Betting.beginHand(state);
+        assert.equal(chipsOnTable(state), start, "dealing moves chips between stacks, not into thin air");
+    });
+
+    test("what the preview promises is what gets posted", () => {
+        const state = makeTable({ seatCount: 9, seated: [1, 3, 6, 8], dealerSeatIndex: 1 });
+        HoldemState.startNextHand(state);
+
+        const preview = Betting.blindPreview(state);
+        Betting.beginHand(state);
+
+        assert.equal(Betting.committed(state.seats[preview.sbIndex]), preview.smallBlind);
+        assert.equal(Betting.committed(state.seats[preview.bbIndex]), preview.bigBlind);
+    });
+
+    test("there's nothing to preview without two players", () => {
+        const alone = makeTable({ seatCount: 6, seated: [2] });
+        HoldemState.startNextHand(alone);
+        assert.equal(Betting.blindPreview(alone), null);
+
+        const empty = makeTable({ seatCount: 6, seated: [] });
+        HoldemState.startNextHand(empty);
+        assert.equal(Betting.blindPreview(empty), null);
+    });
+
+    test("a hand-picked blind shows up in the preview", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        HoldemState.startNextHand(state);
+        state.blindOverride = { sbIndex: 3, bbIndex: 0 };
+
+        const preview = Betting.blindPreview(state);
+        assert.equal(preview.manual, true);
+        assert.equal(preview.sbIndex, 3);
+        assert.equal(preview.bbIndex, 0);
+    });
+});
+
+describe("a table saved mid-hand comes back mid-hand", () => {
+    const loadWith = saved => {
+        const original = globalThis.localStorage;
+        globalThis.localStorage = { getItem: () => JSON.stringify(saved), setItem: () => {}, removeItem: () => {} };
+        const state = HoldemState.load();
+        globalThis.localStorage = original;
+        return state;
+    };
+
+    test("chips already committed mean the betting was open", () => {
+        const state = loadWith({
+            seats: [{ id: "a", name: "Ann", inHand: true, committed: 2 }, { id: "b", name: "Ben", inHand: true, committed: 0 }],
+            handNumber: 3,
+        });
+        assert.equal(state.bettingOpen, true, "otherwise it would offer to deal over a live hand");
+    });
+
+    test("somebody on the clock means the betting was open", () => {
+        const state = loadWith({
+            seats: [{ id: "a", inHand: true }, { id: "b", inHand: true }],
+            actingSeatIndex: 1, handNumber: 2,
+        });
+        assert.equal(state.bettingOpen, true);
+    });
+
+    test("a quiet table comes back waiting to be dealt", () => {
+        const state = loadWith({
+            seats: [{ id: "a", inHand: true }, { id: "b", inHand: true }],
+            actingSeatIndex: null, handNumber: 5,
+        });
+        assert.equal(state.bettingOpen, false);
+    });
+});
+
+describe("the preview tells the truth about the button", () => {
+    test("a button parked on an empty chair is answered for where it will be", () => {
+        // The preview used to read the button where it sat, while dealing relocated it
+        // first — so it promised one pair of blinds and produced another.
+        const state = makeTable({ seatCount: 6, seated: [1, 2, 3], dealerSeatIndex: 0 });
+        state.bettingOpen = false;
+        assert.equal(state.seats[0].inHand, false, "the button is on an empty chair");
+
+        const preview = Betting.blindPreview(state);
+        assert.equal(preview.buttonMoves, true, "and the preview knows it will move");
+
+        Betting.beginHand(state);
+
+        assert.equal(Betting.committed(state.seats[preview.sbIndex]), preview.smallBlind);
+        assert.equal(Betting.committed(state.seats[preview.bbIndex]), preview.bigBlind);
+        assert.equal(state.dealerSeatIndex, preview.buttonIndex, "and it moved where it said");
+    });
+
+    test("asking where the button will be doesn't move it", () => {
+        const state = makeTable({ seatCount: 6, seated: [1, 2, 3], dealerSeatIndex: 0 });
+        state.bettingOpen = false;
+
+        Betting.blindPreview(state);
+        Betting.blindPreview(state);
+
+        assert.equal(state.dealerSeatIndex, 0, "the preview is a question, not an action");
+    });
+
+    test("a button already on a player is left alone", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        state.bettingOpen = false;
+        const preview = Betting.blindPreview(state);
+        assert.equal(preview.buttonMoves, false);
+        assert.equal(preview.buttonIndex, 0);
+    });
+
+    test("buttonSeatForDeal copes with a table nobody is sitting at", () => {
+        const state = makeTable({ seatCount: 6, seated: [] });
+        assert.equal(HoldemState.buttonSeatForDeal(state), state.dealerSeatIndex);
+    });
+});

tests/holdem/historyCache.test.js

@@ -0,0 +1,118 @@
+// The hand-history panel is only rebuilt when its signature changes, which takes a
+// full re-render from ~30ms to ~3ms. The whole saving depends on that signature
+// noticing every way the log can actually change — a stale panel would have the
+// dealer reading last hand's payouts while settling this one.
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { Render, HoldemState, makeTable } = require("./load");
+
+// historySignature() reads Render.state, so point it at a table for each case.
+const signatureOf = state => {
+    Render.state = state;
+    return Render.historySignature();
+};
+
+const tableWithHands = (count) => {
+    const state = makeTable({ seatCount: 4, seated: [0, 1, 2] });
+    for (let i = 0; i < count; i++) {
+        state.seats[0].amountOverride = 2;
+        state.seats[1].amountOverride = 2;
+        HoldemState.recordHand(state, [{ id: state.seats[0].id, label: "Ann", amount: 4 }]);
+    }
+    return state;
+};
+
+describe("the history panel knows when to redraw", () => {
+    test("nothing changes while a hand is being played", () => {
+        const state = tableWithHands(3);
+        const before = signatureOf(state);
+
+        // A whole street of betting touches no part of the log.
+        state.seats[0].committed = 5;
+        state.seats[1].folded = true;
+        state.actingSeatIndex = 2;
+        state.street = "flop";
+
+        assert.equal(signatureOf(state), before, "betting must not force a rebuild");
+    });
+
+    test("settling a hand changes it", () => {
+        const state = tableWithHands(3);
+        const before = signatureOf(state);
+        HoldemState.recordHand(state, [{ id: state.seats[1].id, label: "Ben", amount: 12 }]);
+        assert.notEqual(signatureOf(state), before);
+    });
+
+    test("clearing the history changes it", () => {
+        const state = tableWithHands(5);
+        const before = signatureOf(state);
+        HoldemState.clearHistory(state);
+        assert.notEqual(signatureOf(state), before);
+    });
+
+    test("undoing back to a shorter log changes it", () => {
+        const state = tableWithHands(2);
+        const snapshot = JSON.parse(JSON.stringify(state));
+        HoldemState.recordHand(state, [{ id: state.seats[0].id, label: "Ann", amount: 30 }]);
+        const afterRecord = signatureOf(state);
+
+        // The undo path swaps the state's contents in place.
+        Object.keys(state).forEach(k => delete state[k]);
+        Object.assign(state, snapshot);
+
+        assert.notEqual(signatureOf(state), afterRecord, "an undone hand must disappear from the panel");
+    });
+
+    test("two hands that differ only in payout are told apart", () => {
+        const a = tableWithHands(1);
+        const b = tableWithHands(1);
+        // Same count and hand number; different pot.
+        b.handHistory[0].pot = a.handHistory[0].pot + 25;
+        assert.notEqual(signatureOf(a), signatureOf(b));
+    });
+
+    test("the hand counter moving on changes it", () => {
+        // The counter badge is drawn by the same function, so a new hand number has
+        // to invalidate even when the log itself is untouched.
+        const state = tableWithHands(2);
+        const before = signatureOf(state);
+        state.handNumber += 1;
+        assert.notEqual(signatureOf(state), before);
+    });
+
+    test("an empty log has a stable signature of its own", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1] });
+        const first = signatureOf(state);
+        assert.equal(signatureOf(state), first);
+
+        HoldemState.recordHand(state, [{ id: state.seats[0].id, label: "Ann", amount: 4 }]);
+        assert.notEqual(signatureOf(state), first, "the first hand ever must draw the panel");
+    });
+});
+
+describe("the hand-time cache", () => {
+    test("the same timestamp is only formatted once, and formats the same", () => {
+        Render.handTimeCache.clear();
+        const stamp = Date.UTC(2026, 8, 1, 15, 4);
+        const first = Render.formatHandTime(stamp);
+        assert.equal(Render.handTimeCache.size, 1);
+
+        const second = Render.formatHandTime(stamp);
+        assert.equal(second, first);
+        assert.equal(Render.handTimeCache.size, 1, "not re-formatted");
+    });
+
+    test("different timestamps still format differently", () => {
+        Render.handTimeCache.clear();
+        const a = Render.formatHandTime(Date.UTC(2026, 8, 1, 15, 4));
+        const b = Render.formatHandTime(Date.UTC(2026, 8, 1, 18, 47));
+        assert.notEqual(a, b);
+        assert.equal(Render.handTimeCache.size, 2);
+    });
+
+    test("a nonsense timestamp doesn't throw", () => {
+        Render.handTimeCache.clear();
+        assert.doesNotThrow(() => Render.formatHandTime(undefined));
+        assert.doesNotThrow(() => Render.formatHandTime("not a date"));
+    });
+});

tests/holdem/invariants.test.js

@@ -0,0 +1,213 @@
+// Randomised whole-hand play against the invariants a dealer would notice being broken.
+//
+// These ran once, by hand, in a browser console while the betting engine was being
+// fixed, and then went away with the tab. The bugs they caught (blinds posted to empty
+// chairs, the button skipping players, heads-up acting out of order) are all cases you
+// only hit on a particular table shape, so a fixed set of examples misses them. Keeping
+// the generator means the next change gets checked against the same thousand tables.
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { Betting, PotCalculator, HoldemState, Money, makeTable, chipsOnTable, contributions } = require("./load");
+
+// Deterministic PRNG: a failure has to be reproducible from the seed printed with it,
+// otherwise a randomised suite is just a flaky one.
+function rng(seed) {
+    let s = seed >>> 0;
+    return () => {
+        s = (s * 1664525 + 1013904223) >>> 0;
+        return s / 4294967296;
+    };
+}
+
+// Plays one hand to completion with random but legal-ish dealer input.
+function playHand(random) {
+    const seatCount = 2 + Math.floor(random() * 9);
+    const seatIndexes = [...Array(seatCount).keys()];
+    const seated = seatIndexes.filter(() => random() < 0.7);
+    if (seated.length < 2) seated.push(...seatIndexes.filter(i => !seated.includes(i)).slice(0, 2 - seated.length));
+
+    const bigBlind = [2, 5, 0.5][Math.floor(random() * 3)];
+    const state = makeTable({
+        seatCount,
+        seated,
+        stack: 0,
+        smallBlind: bigBlind / 2,
+        bigBlind,
+        dealerSeatIndex: Math.floor(random() * seatCount),
+    });
+
+    // Varied stack depths, so short stacks and side pots actually happen.
+    seated.forEach(i => {
+        state.seats[i].stack = Money.round(bigBlind * (1 + Math.floor(random() * 60)));
+    });
+
+    const startingChips = chipsOnTable(state);
+    Betting.beginHand(state);
+
+    let guard = 0;
+    while (!Betting.isHandOver(state) && state.street !== "done" && guard++ < 400) {
+        if (state.actingSeatIndex === null) {
+            if (state.street === "river" || !Betting.canStillBet(state)) break;
+            Betting.closeStreet(state);
+            continue;
+        }
+
+        const index = state.actingSeatIndex;
+        const player = state.seats[index];
+        const toCall = Betting.toCall(state, player);
+        const roll = random();
+
+        if (roll < 0.15) Betting.fold(state, index);
+        else if (roll < 0.25) Betting.allIn(state, index);
+        else if (toCall > 0) Betting.call(state, index);
+        else if (roll < 0.75) Betting.check(state, index);
+        else Betting.raiseTo(state, index, Betting.minRaiseTo(state));
+    }
+
+    Betting.sweepToHandTotals(state);
+    return { state, startingChips, seated };
+}
+
+describe("randomised hands hold the dealer's invariants", () => {
+    const HANDS = 1000;
+
+    test(`${HANDS} hands never create or destroy a chip`, () => {
+        const random = rng(20260901);
+        for (let hand = 0; hand < HANDS; hand++) {
+            const { state, startingChips } = playHand(random);
+            assert.equal(
+                chipsOnTable(state),
+                startingChips,
+                `hand ${hand}: chips on the table changed during play`
+            );
+        }
+    });
+
+    test(`${HANDS} hands: pots plus uncalled returns always equal the money in`, () => {
+        const random = rng(778899);
+        let sidePotHands = 0;
+        let returnHands = 0;
+
+        for (let hand = 0; hand < HANDS; hand++) {
+            const { state } = playHand(random);
+            const players = contributions(state);
+            const inThePot = players.reduce((sum, p) => sum + p.contribution, 0);
+            if (inThePot <= 0) continue;
+
+            // Fold flags can leave nobody live, which the calculator deliberately
+            // refuses to guess at — that's a dealer correction, not an invariant.
+            if (players.every(p => p.folded)) continue;
+
+            const layered = PotCalculator.layers(players).reduce((s, l) => s + l.amount, 0);
+            const returned = PotCalculator.uncalledReturns(players).reduce((s, r) => s + r.amount, 0);
+
+            assert.equal(
+                Money.toCents(layered + returned),
+                Money.toCents(inThePot),
+                `hand ${hand}: pot breakdown doesn't add up to what went in`
+            );
+
+            if (PotCalculator.layers(players).length > 1) sidePotHands++;
+            if (returned > 0) returnHands++;
+        }
+
+        assert.ok(sidePotHands > 20, `expected side pots to occur; saw ${sidePotHands}`);
+        assert.ok(returnHands > 20, `expected uncalled bets to occur; saw ${returnHands}`);
+    });
+
+    test(`${HANDS} hands: what's left after returns is money somebody actually matched`, () => {
+        // The rule the pot breakdown rests on: you are only called up to what somebody
+        // else was willing to put in. Once the uncalled chips are handed back, no
+        // player should still be sitting above every other player at the table.
+        //
+        // A single-eligible pot is *not* the thing to look for here — that's legitimate
+        // when a player called and then folded, leaving dead money one contender
+        // collects. The bug this guards against is subtler: chips nobody ever matched
+        // being dressed up as a pot to play for.
+        const random = rng(13579);
+        for (let hand = 0; hand < HANDS; hand++) {
+            const { state } = playHand(random);
+            const players = contributions(state);
+            if (players.every(p => p.folded)) continue;
+
+            const returns = PotCalculator.uncalledReturns(players);
+            assert.ok(returns.length <= 1, `hand ${hand}: only the biggest bet can go uncalled`);
+
+            returns.forEach(r => {
+                const player = players.find(p => p.id === r.id);
+                assert.ok(r.amount <= player.contribution + 0.001, `hand ${hand}: returned more than was put in`);
+            });
+
+            const returned = new Map(returns.map(r => [r.id, r.amount]));
+            const capped = players.map(p => Money.toCents(p.contribution - (returned.get(p.id) || 0)));
+
+            capped.forEach((cents, index) => {
+                const others = capped.filter((_, i) => i !== index);
+                const mostAnyoneElsePaid = others.length ? Math.max(...others) : 0;
+                assert.ok(
+                    cents <= mostAnyoneElsePaid,
+                    `hand ${hand}: a player is still ${Money.fromCents(cents - mostAnyoneElsePaid)} ` +
+                    `above everyone else after returns — that money was never matched`
+                );
+            });
+        }
+    });
+
+    test(`${HANDS} hands: paying the pot out settles it exactly`, () => {
+        const random = rng(24680);
+        for (let hand = 0; hand < HANDS; hand++) {
+            const { state } = playHand(random);
+            const players = contributions(state);
+            if (players.every(p => p.folded)) continue;
+
+            // Take the uncalled money off first, the way the dealer would.
+            const returned = new Map(PotCalculator.uncalledReturns(players).map(r => [r.id, r.amount]));
+            const contested = players.map(p => ({
+                ...p,
+                contribution: Money.round(p.contribution - (returned.get(p.id) || 0)),
+            }));
+
+            let entries = PotCalculator.buildEntries(contested);
+            const potBefore = PotCalculator.totalPot(entries);
+            let paidOut = 0;
+            let rounds = 0;
+
+            while (PotCalculator.getContenders(entries).length > 0 && rounds++ < 30) {
+                const contenders = PotCalculator.getContenders(entries);
+                const winner = contenders[Math.floor(random() * contenders.length)];
+                const result = PotCalculator.resolveRound(entries, [winner.id]);
+                paidOut += result.perWinner.reduce((s, w) => s + w.amount, 0);
+                entries = result.updatedEntries;
+            }
+
+            assert.equal(
+                Money.toCents(paidOut),
+                Money.toCents(potBefore),
+                `hand ${hand}: paying out the pot left ${potBefore - paidOut} unaccounted for`
+            );
+        }
+    });
+
+    test(`${HANDS} hands: the button and blinds land on real players`, () => {
+        const random = rng(112233);
+        for (let hand = 0; hand < HANDS; hand++) {
+            const seatCount = 2 + Math.floor(random() * 9);
+            const seated = [...Array(seatCount).keys()].filter(() => random() < 0.6);
+            if (seated.length < 2) continue;
+
+            const state = makeTable({ seatCount, seated, dealerSeatIndex: Math.floor(random() * seatCount) });
+            HoldemState.advanceButton(state);
+            assert.ok(state.seats[state.dealerSeatIndex].inHand, `hand ${hand}: button on an empty chair`);
+
+            const { sbIndex, bbIndex, headsUp } = HoldemState.getBlindSeats(state);
+            assert.ok(state.seats[sbIndex].inHand, `hand ${hand}: small blind on an empty chair`);
+            assert.ok(state.seats[bbIndex].inHand, `hand ${hand}: big blind on an empty chair`);
+            assert.notEqual(sbIndex, bbIndex, `hand ${hand}: both blinds on one player`);
+
+            if (seated.length === 2) {
+                assert.ok(headsUp, `hand ${hand}: two players should be heads-up`);
+                assert.equal(sbIndex, state.dealerSeatIndex, `hand ${hand}: heads-up button posts the small blind`);
+            }
+        }
+    });
+});

tests/holdem/load.js

@@ -0,0 +1,87 @@
+// Loads the dealer's browser modules into Node so they can be tested directly.
+//
+// The modules are plain script-tag files: each one declares a `const` namespace and
+// ends with a `module.exports` guard. In the browser they find each other as globals,
+// so the same names have to exist on `globalThis` here or `Betting` can't reach
+// `HoldemState`. Load order matches the <script> order in TexasHoldem.cshtml.
+const path = require("path");
+
+const SRC = path.join(__dirname, "..", "..", "JoshHeaps.Net", "wwwroot", "js", "casino", "holdem");
+
+function load(name) {
+    const mod = require(path.join(SRC, `${name}.js`));
+    globalThis[name.charAt(0).toUpperCase() + name.slice(1)] = mod;
+    return mod;
+}
+
+const Money = load("money");
+const PotCalculator = load("potCalculator");
+const SplitCalculator = load("splitCalculator");
+const Betting = load("betting");
+const SettleUp = load("settleUp");
+const HandHistoryExport = load("handHistoryExport");
+
+// render.js exports { Render } rather than the namespace directly.
+const Render = require(path.join(SRC, "render.js")).Render;
+globalThis.Render = Render;
+
+// state.js exports `HoldemState`, which doesn't match its filename.
+const HoldemState = require(path.join(SRC, "state.js"));
+globalThis.HoldemState = HoldemState;
+
+// ---- Table builders ----------------------------------------------------------
+
+// A table with `seatCount` chairs where `seated` (a list of seat indexes) are dealt
+// in with `stack` chips each. Everything else is the app's own defaults, so a test
+// that forgets to set a field gets whatever a real dealer would get.
+function makeTable({ seatCount = 6, seated = null, stack = 100, smallBlind = 1, bigBlind = 2, dealerSeatIndex = 0 } = {}) {
+    const state = HoldemState.createDefault();
+    HoldemState.resizeSeats(state, seatCount);
+    state.smallBlind = smallBlind;
+    state.bigBlind = bigBlind;
+    state.dealerSeatIndex = dealerSeatIndex;
+
+    const sitting = seated || state.seats.map((_, i) => i);
+    state.seats.forEach((player, index) => {
+        player.inHand = sitting.includes(index);
+        player.stack = sitting.includes(index) ? stack : null;
+        player.name = `P${index + 1}`;
+    });
+    return state;
+}
+
+// Total chips the table is accountable for: what's in front of everyone, plus what
+// they've pushed in this street, plus what's already banked into the pot.
+function chipsOnTable(state) {
+    return Money.round(
+        state.seats.reduce(
+            (sum, p) => sum + (Number(p.stack) || 0) + (Number(p.committed) || 0) + (Number(p.amountOverride) || 0),
+            0
+        )
+    );
+}
+
+// Contributions in the shape PotCalculator wants them.
+function contributions(state) {
+    return state.seats
+        .filter(p => p.inHand)
+        .map(p => ({
+            id: p.id,
+            contribution: Betting.handTotal(p),
+            folded: p.folded,
+        }));
+}
+
+module.exports = {
+    Money,
+    Render,
+    HandHistoryExport,
+    PotCalculator,
+    SplitCalculator,
+    SettleUp,
+    Betting,
+    HoldemState,
+    makeTable,
+    chipsOnTable,
+    contributions,
+};

tests/holdem/messyTables.test.js

@@ -0,0 +1,260 @@
+// Home games are messy. People walk up mid-hand, storm off mid-hand, argue about
+// whose blind it is, and pass the button round three times before anyone deals.
+// These are the cases the positional rules quietly get wrong.
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { Betting, HoldemState, PotCalculator, Money, makeTable, chipsOnTable, contributions } = require("./load");
+
+const potOf = state => HoldemState.totalPot(state);
+
+describe("a player leaves in the middle of a hand", () => {
+    test("their chips stay in the pot", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.call(state, 3); Betting.call(state, 0); Betting.call(state, 1); Betting.check(state, 2);
+        Betting.sweepToHandTotals(state);
+
+        const before = potOf(state);
+        assert.equal(before, 8);
+
+        state.seats[1].inHand = false; // dealer takes them out
+
+        assert.equal(potOf(state), before, "the pot must not shrink when a player is taken out");
+    });
+
+    test("they cannot be paid out of a pot they walked away from", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.call(state, 0); Betting.call(state, 1); Betting.check(state, 2);
+        Betting.sweepToHandTotals(state);
+
+        state.seats[1].inHand = false;
+
+        const players = state.seats
+            .filter(p => HoldemState.computeContribution(p, state.chipLegend, state.basePotAmount) > 0)
+            .map(p => ({
+                id: p.id,
+                contribution: HoldemState.computeContribution(p, state.chipLegend, state.basePotAmount),
+                folded: p.folded || HoldemState.isDeadMoney(p),
+            }));
+
+        const layers = PotCalculator.layers(players);
+        assert.ok(!layers[0].eligible.includes(state.seats[1].id), "a departed player can't win");
+        assert.equal(layers.reduce((s, l) => s + l.amount, 0), 6, "but their money is still being played for");
+    });
+
+    test("taking out the player who is to act moves the action on", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        const acting = state.actingSeatIndex;
+
+        state.seats[acting].inHand = false;
+        Betting.passAction(state, acting);
+
+        assert.notEqual(state.actingSeatIndex, acting, "the table can't wait on somebody who left");
+        assert.ok(state.actingSeatIndex === null || state.seats[state.actingSeatIndex].inHand);
+    });
+
+    test("an empty chair still contributes nothing, base pot or not", () => {
+        // The table-wide default must not be read as an ante from seats nobody is in.
+        const state = makeTable({ seatCount: 6, seated: [0, 1], dealerSeatIndex: 0 });
+        state.basePotAmount = 25;
+        assert.equal(HoldemState.computeContribution(state.seats[4], state.chipLegend, 25), 0);
+    });
+});
+
+describe("a player joins in the middle of a hand", () => {
+    test("they sit the hand out rather than joining a pot they never paid into", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.call(state, 0); Betting.call(state, 1); Betting.check(state, 2);
+        Betting.sweepToHandTotals(state);
+
+        // Walks up and is dealt in — the app marks them folded for this hand.
+        state.seats[4].inHand = true;
+        state.seats[4].stack = 100;
+        state.seats[4].folded = true;
+
+        assert.ok(!Betting.liveSeats(state).some(s => s.index === 4), "not live this hand");
+        assert.equal(HoldemState.computeContribution(state.seats[4], state.chipLegend, state.basePotAmount), 0);
+    });
+
+    test("they are a full player again on the next hand", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        state.seats[4].inHand = true;
+        state.seats[4].stack = 100;
+        state.seats[4].folded = true;
+
+        HoldemState.startNextHand(state);
+        Betting.beginHand(state);
+
+        assert.equal(state.seats[4].folded, false);
+        assert.ok(Betting.liveSeats(state).some(s => s.index === 4), "dealt in like anyone else");
+    });
+});
+
+describe("passing the button around before the cards come out", () => {
+    test("moving the button re-posts the blinds and keeps the chip count straight", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        const startingChips = chipsOnTable(state);
+        Betting.beginHand(state);
+
+        assert.equal(state.seats[1].committed, 1);
+        assert.equal(state.seats[2].committed, 2);
+
+        state.dealerSeatIndex = 2;
+        Betting.repostBlinds(state);
+
+        assert.equal(state.seats[1].committed, 0, "the old small blind got their chip back");
+        assert.equal(state.seats[3].committed, 1, "and the new one has posted");
+        assert.equal(state.seats[0].committed, 2);
+        assert.equal(chipsOnTable(state), startingChips, "no chips created or lost in the shuffle");
+    });
+
+    test("passing it round many times still balances", () => {
+        const state = makeTable({ seatCount: 8, seated: [0, 2, 3, 5, 7], dealerSeatIndex: 0 });
+        const startingChips = chipsOnTable(state);
+        Betting.beginHand(state);
+
+        [2, 5, 7, 3, 0, 5].forEach(seat => {
+            state.dealerSeatIndex = seat;
+            Betting.repostBlinds(state);
+            assert.equal(chipsOnTable(state), startingChips, `chips drifted after passing to seat ${seat}`);
+        });
+
+        const { sbIndex, bbIndex } = HoldemState.getBlindSeats(state);
+        assert.equal(Betting.committed(state.seats[sbIndex]), 1);
+        assert.equal(Betting.committed(state.seats[bbIndex]), 2);
+    });
+
+    test("once somebody has acted, the blinds are settled", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        assert.equal(Betting.onlyBlindsIn(state), true, "nothing but blinds so far");
+
+        Betting.call(state, 3);
+        assert.equal(Betting.onlyBlindsIn(state), false, "a call means the blinds are set where they are");
+    });
+});
+
+describe("naming the blinds by hand", () => {
+    test("a named blind wins over the button order", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        state.blindOverride = { sbIndex: 3, bbIndex: 0 };
+
+        const { sbIndex, bbIndex, manual } = HoldemState.getBlindSeats(state);
+        assert.equal(sbIndex, 3);
+        assert.equal(bbIndex, 0);
+        assert.equal(manual, true);
+
+        Betting.beginHand(state);
+        assert.equal(state.seats[3].committed, 1);
+        assert.equal(state.seats[0].committed, 2);
+        assert.equal(state.seats[1].committed, 0, "the positional small blind posts nothing");
+    });
+
+    test("a named blind on a player who isn't dealt in is ignored", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        state.blindOverride = { sbIndex: 4, bbIndex: 0 }; // seat 4 is an empty chair
+
+        const { sbIndex, manual } = HoldemState.getBlindSeats(state);
+        assert.ok(!manual, "falls back to the button order rather than posting to nobody");
+        assert.ok(state.seats[sbIndex].inHand);
+    });
+
+    test("both blinds on one player is refused", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        state.blindOverride = { sbIndex: 1, bbIndex: 1 };
+        const { sbIndex, bbIndex } = HoldemState.getBlindSeats(state);
+        assert.notEqual(sbIndex, bbIndex);
+    });
+
+    test("naming blinds heads-up still acts in the right order", () => {
+        const state = makeTable({ seatCount: 6, seated: [2, 5], dealerSeatIndex: 2 });
+        state.blindOverride = { sbIndex: 5, bbIndex: 2 }; // deliberately the reverse
+
+        Betting.beginHand(state);
+        assert.equal(state.seats[5].committed, 1);
+        assert.equal(state.seats[2].committed, 2);
+        assert.equal(state.actingSeatIndex, 5, "the small blind acts first pre-flop heads-up");
+
+        Betting.call(state, 5);
+        Betting.check(state, 2);
+        Betting.closeStreet(state);
+        assert.equal(state.actingSeatIndex, 2, "and the big blind leads after the flop");
+    });
+
+    test("the naming only lasts the hand it was made for", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        state.blindOverride = { sbIndex: 3, bbIndex: 0 };
+        Betting.beginHand(state);
+
+        HoldemState.startNextHand(state);
+        assert.equal(state.blindOverride, null, "blinds go back to following the button");
+    });
+});
+
+describe("the first hand on a fresh table", () => {
+    test("the button never starts on an empty chair", () => {
+        const state = HoldemState.createDefault();
+        HoldemState.resizeSeats(state, 9);
+        [4, 6, 7].forEach(i => { state.seats[i].inHand = true; state.seats[i].stack = 100; });
+        assert.equal(state.dealerSeatIndex, 0, "a fresh table starts the button on seat 1");
+        assert.equal(state.seats[0].inHand, false, "which nobody is sitting in");
+
+        Betting.beginHand(state);
+
+        assert.ok(state.seats[state.dealerSeatIndex].inHand, "the button moved to a real player");
+        const { sbIndex, bbIndex } = HoldemState.getBlindSeats(state);
+        assert.ok(state.seats[sbIndex].inHand);
+        assert.ok(state.seats[bbIndex].inHand);
+        assert.notEqual(sbIndex, bbIndex);
+    });
+
+    test("a table that empties out around the button recovers", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 3 });
+        state.seats[3].inHand = false; // the player holding the button leaves
+        HoldemState.ensureButtonOnPlayer(state);
+        assert.ok(state.seats[state.dealerSeatIndex].inHand);
+    });
+
+    test("two players left after everyone else walks is heads-up, blinds reversed", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        [2, 3].forEach(i => { state.seats[i].inHand = false; });
+
+        HoldemState.startNextHand(state);
+        Betting.beginHand(state);
+
+        const { sbIndex, headsUp } = HoldemState.getBlindSeats(state);
+        assert.equal(headsUp, true);
+        assert.equal(sbIndex, state.dealerSeatIndex, "heads-up the button posts the small blind");
+    });
+});
+
+describe("chips survive a messy table", () => {
+    test("joining, leaving and passing the button never changes the chip count", () => {
+        const state = makeTable({ seatCount: 8, seated: [0, 1, 2, 3], stack: 100, dealerSeatIndex: 0 });
+        state.seats[6].stack = 100; // sitting down but not dealt in yet
+        const startingChips = chipsOnTable(state);
+
+        Betting.beginHand(state);
+        state.dealerSeatIndex = 2;
+        Betting.repostBlinds(state);
+
+        state.seats[6].inHand = true;   // walks up mid-hand
+        state.seats[6].folded = true;
+        assert.equal(chipsOnTable(state), startingChips);
+
+        Betting.call(state, state.actingSeatIndex);
+        state.seats[1].inHand = false;  // and someone storms off
+        Betting.sweepToHandTotals(state);
+
+        assert.equal(chipsOnTable(state), startingChips, "every chip is still accounted for");
+        assert.equal(
+            Money.toCents(potOf(state) + state.seats.reduce((s, p) => s + (Number(p.stack) || 0), 0)),
+            Money.toCents(startingChips),
+            "and the pot plus the stacks is the whole table"
+        );
+    });
+});

tests/holdem/money.test.js

@@ -0,0 +1,126 @@
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { Money, HandHistoryExport } = require("./load");
+
+describe("Money.format", () => {
+    test("whole amounts drop the pointless cents", () => {
+        assert.equal(Money.format(12), "$12");
+        assert.equal(Money.format(450), "$450");
+        assert.equal(Money.format(1250000), "$1,250,000");
+        assert.equal(Money.format(0), "$0");
+    });
+
+    test("amounts that carry cents still show them", () => {
+        assert.equal(Money.format(12.5), "$12.50");
+        assert.equal(Money.format(0.25), "$0.25");
+        assert.equal(Money.format(3.01), "$3.01");
+    });
+
+    test("a quarter-blind game reads exactly as it did", () => {
+        // The case that would be ruined by dropping cents unconditionally.
+        [0.25, 0.5, 1.75, 12.05].forEach(v => {
+            assert.match(Money.format(v), /\.\d\d$/, `${v} lost its cents`);
+        });
+    });
+
+    test("floating-point dust doesn't invent cents", () => {
+        assert.equal(Money.format(0.1 + 0.2), "$0.30");
+        assert.equal(Money.format(1.0000000001), "$1");
+    });
+
+    test("signed amounts put the sign out front, both scales", () => {
+        assert.equal(Money.formatSigned(87500), "+$87,500");
+        assert.equal(Money.formatSigned(-87500), "-$87,500");
+        assert.equal(Money.formatSigned(-12.5), "-$12.50");
+        assert.equal(Money.formatSigned(0), "$0");
+    });
+
+    test("rubbish in doesn't produce rubbish out", () => {
+        assert.equal(Money.format(null), "$0");
+        assert.equal(Money.format(undefined), "$0");
+        assert.equal(Money.format("nonsense"), "$0");
+    });
+});
+
+describe("Money.forSheet", () => {
+    test("a bare number a spreadsheet will add up", () => {
+        assert.equal(Money.forSheet(1250000), "1250000.00");
+        assert.equal(Money.forSheet(12.5), "12.50");
+        assert.equal(Money.forSheet(-87500), "-87500.00");
+    });
+
+    test("no currency symbol and no thousands separators", () => {
+        const written = Money.forSheet(1234567.89);
+        assert.ok(!written.includes("$"), "a $ makes the cell text");
+        assert.ok(!written.includes(","), "a comma makes the cell text");
+        assert.equal(Number(written), 1234567.89, "and it parses straight back to a number");
+    });
+});
+
+describe("the exported CSV", () => {
+    const history = [
+        { handNumber: 2, timestamp: 0, pot: 1250000, payouts: [{ id: "a", label: "Alexandra", amount: 1250000 }] },
+        { handNumber: 1, timestamp: 0, pot: 24.5, payouts: [{ id: "b", label: "Bob", amount: 24.5 }] },
+    ];
+    const standings = [
+        { id: "a", name: "Alexandra", in: 1250000, won: 1250000, net: 0, boughtIn: 3200000, chipsNow: 3200000, cashPosition: 0 },
+        { id: "b", name: "Bob", in: 24.5, won: 0, net: -24.5, boughtIn: 100, chipsNow: 75.5, cashPosition: -24.5 },
+    ];
+
+    // Splitting on commas isn't good enough: the timestamp column legitimately holds
+    // one ("1/1/1970, 5:00:00 PM") and is quoted for exactly that reason.
+    const splitRow = line => {
+        const fields = [];
+        let field = "";
+        let quoted = false;
+        for (let i = 0; i < line.length; i++) {
+            const c = line[i];
+            if (quoted) {
+                if (c === '"' && line[i + 1] === '"') { field += '"'; i++; }
+                else if (c === '"') quoted = false;
+                else field += c;
+            } else if (c === '"') quoted = true;
+            else if (c === ",") { fields.push(field); field = ""; }
+            else field += c;
+        }
+        fields.push(field);
+        return fields;
+    };
+
+    test("every money cell parses as a number", () => {
+        const csv = HandHistoryExport.toCsv(history, standings);
+        const lines = csv.split("\r\n");
+
+        lines.slice(1, 3).forEach(line => {
+            const cell = splitRow(line)[2]; // Pot
+            assert.ok(cell !== "" && !Number.isNaN(Number(cell)), `pot cell "${cell}" isn't a number`);
+        });
+
+        // Standings rows: every column after the name has to be numeric.
+        const standingsStart = lines.findIndex(l => l.startsWith("Player,"));
+        lines.slice(standingsStart + 1).filter(Boolean).forEach(line => {
+            splitRow(line).slice(1).forEach(cell => {
+                assert.ok(cell !== "" && !Number.isNaN(Number(cell)), `standings cell "${cell}" isn't a number`);
+            });
+        });
+    });
+
+    test("a million-dollar pot doesn't need quoting any more", () => {
+        const csv = HandHistoryExport.toCsv(history, []);
+        assert.ok(csv.includes("1250000.00"), "written plainly");
+        assert.ok(!csv.includes('"$1,250,000'), "not as a quoted, unsummable string");
+    });
+
+    test("names and payout descriptions stay human", () => {
+        const csv = HandHistoryExport.toCsv(history, standings);
+        assert.ok(csv.includes("Alexandra"), "the name column is still a name");
+        assert.ok(csv.includes("Alexandra: $1,250,000"), "the payout column still reads like a sentence");
+    });
+
+    test("a name with a comma is still quoted properly", () => {
+        const csv = HandHistoryExport.toCsv([], [
+            { id: "x", name: "Smith, John", in: 0, won: 0, net: 0, boughtIn: 0, chipsNow: 0, cashPosition: 0 },
+        ]);
+        assert.ok(csv.includes('"Smith, John"'), "the CSV escaping still applies where it's needed");
+    });
+});

tests/holdem/potCalculator.test.js

@@ -0,0 +1,124 @@
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { PotCalculator } = require("./load");
+
+const p = (id, contribution, folded = false) => ({ id, contribution, folded });
+
+describe("PotCalculator.layers", () => {
+    test("one pot when everyone put in the same", () => {
+        const layers = PotCalculator.layers([p("a", 50), p("b", 50), p("c", 50)]);
+        assert.equal(layers.length, 1);
+        assert.equal(layers[0].amount, 150);
+        assert.equal(layers[0].label, "Main pot");
+        assert.deepEqual(layers[0].eligible.sort(), ["a", "b", "c"]);
+    });
+
+    test("a short all-in opens a side pot only the deeper players can win", () => {
+        // a is all-in for 20, b and c keep betting to 60.
+        const layers = PotCalculator.layers([p("a", 20), p("b", 60), p("c", 60)]);
+        assert.equal(layers.length, 2);
+
+        assert.equal(layers[0].amount, 60); // 20 x 3
+        assert.deepEqual(layers[0].eligible.sort(), ["a", "b", "c"]);
+
+        assert.equal(layers[1].amount, 80); // 40 x 2
+        assert.deepEqual(layers[1].eligible.sort(), ["b", "c"]);
+        assert.equal(layers[1].label, "Side pot 1");
+    });
+
+    test("folded money stays in the pot as dead money but wins nothing", () => {
+        const layers = PotCalculator.layers([p("a", 50), p("b", 50), p("folder", 50, true)]);
+        assert.equal(layers.length, 1);
+        assert.equal(layers[0].amount, 150, "the folder's chips are still in the middle");
+        assert.ok(!layers[0].eligible.includes("folder"));
+    });
+
+    test("layers with the same eligible players are announced as one pot", () => {
+        // Two folders at different heights would each open a band, but a dealer
+        // announces one pot between the two players who can actually win it.
+        const layers = PotCalculator.layers([
+            p("a", 100),
+            p("b", 100),
+            p("f1", 20, true),
+            p("f2", 40, true),
+        ]);
+        const eligibleSets = layers.map(l => l.eligible.slice().sort().join(","));
+        assert.deepEqual(eligibleSets, ["a,b"], "one announceable pot, not three");
+        assert.equal(layers[0].amount, 260);
+    });
+
+    test("layer amounts always sum to the contested money", () => {
+        const players = [p("a", 12.5), p("b", 33.25), p("c", 33.25), p("d", 5, true)];
+        const total = players.reduce((s, x) => s + x.contribution, 0);
+        const uncalled = PotCalculator.uncalledReturns(players).reduce((s, r) => s + r.amount, 0);
+        const layered = PotCalculator.layers(players).reduce((s, l) => s + l.amount, 0);
+        assert.equal(Math.round((layered + uncalled) * 100), Math.round(total * 100));
+    });
+
+    test("nobody contributed means no pots, not an empty main pot", () => {
+        assert.deepEqual(PotCalculator.layers([p("a", 0), p("b", 0)]), []);
+    });
+});
+
+describe("PotCalculator.uncalledReturns", () => {
+    test("an overbet nobody called goes back to whoever bet it", () => {
+        // b shoves 200, a calls only 50 and everyone else folds.
+        const returns = PotCalculator.uncalledReturns([p("a", 50), p("b", 200)]);
+        assert.deepEqual(returns, [{ id: "b", amount: 150 }]);
+    });
+
+    test("a called bet leaves nothing to return", () => {
+        assert.deepEqual(PotCalculator.uncalledReturns([p("a", 50), p("b", 50)]), []);
+    });
+
+    test("the cap is the biggest live contribution, so a folder's overbet comes back", () => {
+        const returns = PotCalculator.uncalledReturns([p("live", 30), p("bully", 90, true)]);
+        assert.deepEqual(returns, [{ id: "bully", amount: 60 }]);
+    });
+
+    test("with nobody live it stays quiet rather than refunding the table", () => {
+        // Every fold flag set is a dealer mistake to correct, not a signal that
+        // every chip on the felt was uncalled.
+        assert.deepEqual(PotCalculator.uncalledReturns([p("a", 10, true), p("b", 20, true)]), []);
+    });
+});
+
+describe("PotCalculator.resolveRound", () => {
+    test("a single winner takes the layer they were matched for", () => {
+        const entries = PotCalculator.buildEntries([p("a", 50), p("b", 50)]);
+        const result = PotCalculator.resolveRound(entries, ["a"]);
+        assert.equal(result.payoutPool, 100);
+        assert.deepEqual(result.perWinner, [{ id: "a", amount: 100 }]);
+        assert.equal(result.remainingContenders.length, 0);
+    });
+
+    test("an all-in winner only takes what everyone matched, the rest rolls forward", () => {
+        const entries = PotCalculator.buildEntries([p("short", 20), p("b", 60), p("c", 60)]);
+        const result = PotCalculator.resolveRound(entries, ["short"]);
+        assert.equal(result.capApplied, 20);
+        assert.equal(result.payoutPool, 60, "20 from each of three players");
+        // b and c still have 40 each left to play for.
+        assert.deepEqual(result.remainingContenders.map(e => e.id).sort(), ["b", "c"]);
+        assert.equal(PotCalculator.totalPot(result.updatedEntries), 80);
+    });
+
+    test("a chopped pot splits evenly", () => {
+        const entries = PotCalculator.buildEntries([p("a", 30), p("b", 30)]);
+        const result = PotCalculator.resolveRound(entries, ["a", "b"]);
+        assert.deepEqual(result.perWinner, [{ id: "a", amount: 30 }, { id: "b", amount: 30 }]);
+    });
+
+    test("odd cents go to the winners in selection order and nothing is lost", () => {
+        // A $10.01 pot three ways doesn't divide: 3.34 / 3.34 / 3.33.
+        const entries = PotCalculator.buildEntries([p("a", 3.34), p("b", 3.34), p("c", 3.33)]);
+        const result = PotCalculator.resolveRound(entries, ["a", "b", "c"]);
+        const paid = result.perWinner.reduce((s, w) => s + w.amount, 0);
+        assert.equal(Math.round(paid * 100), Math.round(result.payoutPool * 100), "no chips lost to rounding");
+        assert.ok(result.perWinner[0].amount >= result.perWinner[2].amount, "odd cent goes to the first selected");
+    });
+
+    test("selecting nobody who can win is an error, not a silent no-op", () => {
+        const entries = PotCalculator.buildEntries([p("a", 50), p("b", 50)]);
+        assert.throws(() => PotCalculator.resolveRound(entries, ["ghost"]), /No valid winners/);
+    });
+});

tests/holdem/potSafety.test.js

@@ -0,0 +1,103 @@
+// Chips only ever leave this tool because a dealer meant them to. Starting the next
+// hand clears every seat's contribution, so an unresolved pot is simply destroyed —
+// the UI now asks first, and the number it quotes has to be exactly what goes.
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { Betting, HoldemState, Money, makeTable, chipsOnTable } = require("./load");
+
+// The same measure the confirmation uses.
+const unresolvedPot = state => HoldemState.unresolvedContributions(state);
+
+describe("what starting the next hand destroys", () => {
+    test("the quoted amount is exactly what leaves the table", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.call(state, 3); Betting.call(state, 0); Betting.call(state, 1); Betting.check(state, 2);
+        Betting.sweepToHandTotals(state);
+
+        const before = chipsOnTable(state);
+        const quoted = unresolvedPot(state);
+        assert.ok(quoted > 0, "there is a pot to warn about");
+
+        HoldemState.startNextHand(state);
+
+        assert.equal(
+            Money.toCents(chipsOnTable(state)),
+            Money.toCents(before - quoted),
+            "the dealer must be told the real number, not an approximation"
+        );
+    });
+
+    test("chips still in front of players on the current street are counted too", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        Betting.beginHand(state);          // blinds are `committed`, not yet banked
+        Betting.raiseTo(state, 0, 25);     // and so is a raise mid-street
+
+        const before = chipsOnTable(state);
+        const quoted = unresolvedPot(state);
+        HoldemState.startNextHand(state);
+
+        assert.equal(Money.toCents(chipsOnTable(state)), Money.toCents(before - quoted));
+        assert.ok(quoted >= 25, `a live raise has to be included; quoted ${quoted}`);
+    });
+
+    test("a hand that was paid out properly leaves nothing to warn about", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.call(state, 0); Betting.call(state, 1); Betting.check(state, 2);
+        Betting.sweepToHandTotals(state);
+
+        const pot = HoldemState.totalPot(state);
+        const payouts = [{ id: state.seats[0].id, label: "Ann", amount: pot }];
+        HoldemState.recordHand(state, payouts);
+        Betting.creditWinnings(state, payouts);
+        HoldemState.startNextHand(state);
+
+        assert.equal(unresolvedPot(state), 0, "nothing left over after a settled hand");
+    });
+
+    test("settling then dealing on conserves every chip", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        const start = chipsOnTable(state);
+
+        for (let hand = 0; hand < 5; hand++) {
+            Betting.beginHand(state);
+            const live = Betting.liveSeats(state);
+            live.forEach(s => { if (Betting.toCall(state, s.player) > 0) Betting.call(state, s.index); });
+            Betting.sweepToHandTotals(state);
+
+            const pot = HoldemState.totalPot(state);
+            const winner = Betting.liveSeats(state)[0];
+            const payouts = [{ id: winner.player.id, label: "w", amount: pot }];
+            HoldemState.recordHand(state, payouts);
+            Betting.creditWinnings(state, payouts);
+            HoldemState.startNextHand(state);
+
+            assert.equal(chipsOnTable(state), start, `chips drifted on hand ${hand + 1}`);
+        }
+    });
+
+    test("an empty table has no phantom pot to warn about", () => {
+        const state = makeTable({ seatCount: 6, seated: [] });
+        assert.equal(unresolvedPot(state), 0);
+    });
+
+    test("a standing ante is never warned about, because it isn't lost", () => {
+        // The table default is a stand-in for "everyone puts the same in every hand",
+        // used by a dealer not tracking stacks at all. It re-applies to the next hand
+        // rather than going anywhere, so counting it would nag this dealer before
+        // every single hand — which is why the warning measures the fields
+        // startNextHand actually clears rather than the pot badge.
+        const state = makeTable({ seatCount: 9, seated: [0, 1] });
+        state.basePotAmount = 25;
+        state.seats.forEach(p => { p.amountOverride = null; });
+
+        // The base pot carries into the next hand, so nothing is being thrown away
+        // and the dealer must not be asked to confirm anything.
+        assert.equal(HoldemState.totalPot(state), 50, "the badge still shows a pot");
+        assert.equal(unresolvedPot(state), 0, "but none of it is at risk, so no warning");
+
+        HoldemState.startNextHand(state);
+        assert.equal(HoldemState.totalPot(state), 50, "the standing ante applies to the new hand too");
+    });
+});

tests/holdem/reopeningBetting.test.js

@@ -0,0 +1,143 @@
+// When does a bet reopen the action? The most misread rule in poker, and the one a
+// home game argues about longest: a player shoving in less than a full raise does not
+// give everybody behind them another go.
+//
+// TDA Rule 44 — an all-in wager of less than a full raise does not reopen the betting
+// to a player who has already acted and is not facing a full raise.
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { Betting, makeTable, chipsOnTable } = require("./load");
+
+const actedFlags = state => state.seats
+    .map((p, i) => ({ seat: i, acted: p.hasActed, live: p.inHand && !p.folded }))
+    .filter(s => s.live);
+
+describe("a short all-in does not reopen the betting", () => {
+    // Blinds 1/2. Seat 4 raises to 10 (a full raise of 8). Seat 1 calls.
+    // Seat 2 is all-in for 13 — three more, where a full raise needs eight.
+    const shortAllInTable = () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], stack: 100, dealerSeatIndex: 0 });
+        state.seats[1].stack = 13;
+        Betting.beginHand(state);
+        Betting.raiseTo(state, 3, 10);
+        Betting.call(state, 0);
+        return state;
+    };
+
+    test("players who already acted are not asked to act again", () => {
+        const state = shortAllInTable();
+        assert.equal(state.seats[0].hasActed, true, "seat 1 has called");
+        assert.equal(state.seats[3].hasActed, true, "seat 4 has raised");
+
+        Betting.allIn(state, 1);
+
+        assert.equal(state.seats[0].hasActed, true, "seat 1 must not be reopened");
+        assert.equal(state.seats[3].hasActed, true, "seat 4 must not be reopened");
+    });
+
+    test("but they do still owe the difference", () => {
+        const state = shortAllInTable();
+        Betting.allIn(state, 1);
+
+        assert.equal(Betting.toCall(state, state.seats[0]), 3, "seat 1 owes the extra 3");
+        assert.equal(Betting.isStreetComplete(state), false, "so the street isn't over");
+    });
+
+    test("a player who had not acted yet keeps full rights", () => {
+        const state = shortAllInTable();
+        assert.equal(state.seats[2].hasActed, false, "seat 3 hasn't acted");
+        Betting.allIn(state, 1);
+        assert.equal(state.seats[2].hasActed, false, "and still hasn't — they may still raise");
+    });
+
+    test("the minimum raise is not shrunk by the short all-in", () => {
+        const state = shortAllInTable();
+        assert.equal(state.lastRaiseSize, 8);
+
+        Betting.allIn(state, 1);
+
+        assert.equal(state.lastRaiseSize, 8, "still the last *full* raise");
+        assert.equal(Betting.minRaiseTo(state), 21, "13 to call plus a full raise of 8");
+    });
+
+    test("calling the short all-in ends the street", () => {
+        const state = shortAllInTable();
+        Betting.allIn(state, 1);
+        Betting.call(state, 2);   // seat 3, who had full rights, just calls
+        Betting.call(state, 3);
+        Betting.call(state, 0);
+        assert.equal(Betting.isStreetComplete(state), true);
+    });
+
+    test("no chips are created or lost by any of it", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], stack: 100, dealerSeatIndex: 0 });
+        state.seats[1].stack = 13;
+        const start = chipsOnTable(state);
+        Betting.beginHand(state);
+        Betting.raiseTo(state, 3, 10);
+        Betting.call(state, 0);
+        Betting.allIn(state, 1);
+        Betting.call(state, 2);
+        Betting.call(state, 3);
+        Betting.call(state, 0);
+        assert.equal(chipsOnTable(state), start);
+    });
+});
+
+describe("a full raise still reopens the betting", () => {
+    test("an all-in that is a full raise or more reopens everyone", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], stack: 100, dealerSeatIndex: 0 });
+        state.seats[1].stack = 40;
+        Betting.beginHand(state);
+        Betting.raiseTo(state, 3, 10);
+        Betting.call(state, 0);
+
+        Betting.allIn(state, 1);   // to 40: an increase of 30, well over the 8 needed
+
+        assert.equal(state.seats[0].hasActed, false, "seat 1 gets another go");
+        assert.equal(state.seats[3].hasActed, false, "and so does seat 4");
+        assert.equal(state.lastRaiseSize, 30);
+        assert.equal(Betting.minRaiseTo(state), 70);
+    });
+
+    test("an ordinary raise reopens everyone", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.call(state, 3);
+        Betting.call(state, 0);
+        assert.equal(state.seats[3].hasActed, true);
+
+        Betting.raiseTo(state, 1, 10);
+
+        assert.equal(state.seats[3].hasActed, false);
+        assert.equal(state.seats[0].hasActed, false);
+    });
+
+    test("a raise exactly the size of the last one counts as full", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], stack: 100, dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.raiseTo(state, 3, 10);      // raise of 8
+        Betting.call(state, 0);
+
+        Betting.raiseTo(state, 1, 18);      // exactly 8 more — a legal minimum raise
+
+        assert.equal(state.seats[0].hasActed, false, "a minimum raise still reopens");
+        assert.equal(state.lastRaiseSize, 8);
+    });
+
+    test("the first raise of a street is measured against the big blind", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2, 3], stack: 100, dealerSeatIndex: 0 });
+        Betting.beginHand(state);
+        Betting.call(state, 3);
+        Betting.call(state, 0);
+        Betting.call(state, 1);
+        Betting.check(state, 2);
+        Betting.closeStreet(state);         // to the flop, no bet yet
+
+        const first = Betting.nextToAct(state, state.dealerSeatIndex);
+        Betting.raiseTo(state, first, 2);   // a bet of exactly one big blind
+
+        const others = state.seats.filter((p, i) => p.inHand && !p.folded && i !== first);
+        assert.ok(others.every(p => p.hasActed === false), "a full-sized opening bet reopens everyone");
+    });
+});

tests/holdem/robustness.test.js

@@ -0,0 +1,144 @@
+// Values a dealer can actually produce with a typo, and the ones a corrupted save
+// can produce on its own. None of these should be able to move chips.
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { Betting, HoldemState, makeTable, chipsOnTable } = require("./load");
+
+describe("a stack can never go negative", () => {
+    test("a mistyped negative stack reads as empty, not as owing chips", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2] });
+        state.seats[0].stack = -50;
+        assert.equal(Betting.stackOf(state, state.seats[0]), 0);
+    });
+
+    test("a negative stack can't be bet with", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2] });
+        state.seats[0].stack = -50;
+        const before = state.seats.reduce((s, p) => s + Math.max(0, Number(p.stack) || 0), 0);
+
+        const moved = Betting.putIn(state, 0, 25);
+
+        assert.equal(moved, 0, "nothing moves out of an empty stack");
+        assert.ok(Betting.stackOf(state, state.seats[0]) >= 0);
+        assert.equal(state.seats[0].committed, 0, "and nothing appears in front of them");
+        assert.ok(state.seats.reduce((s, p) => s + Math.max(0, Number(p.stack) || 0), 0) <= before);
+    });
+
+    test("a negative table default doesn't hand everyone a negative stack", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2] });
+        state.seats.forEach(p => { p.stack = null; });
+        state.defaultStack = -100;
+        state.seats.forEach(p => assert.equal(Betting.stackOf(state, p), 0));
+    });
+
+    test("a negative stack doesn't make a player look like they can still bet", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2] });
+        state.seats[0].stack = -50;
+        assert.ok(!Betting.seatsWithChips(state).some(s => s.index === 0));
+    });
+});
+
+describe("blinds that can't be posted", () => {
+    test("negative blinds post nothing rather than paying players to sit down", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2] });
+        state.smallBlind = -5;
+        state.bigBlind = -10;
+        const before = chipsOnTable(state);
+
+        Betting.beginHand(state);
+
+        state.seats.forEach(p => assert.equal(p.committed, 0));
+        assert.equal(chipsOnTable(state), before);
+    });
+
+    test("an unreadable blind doesn't wedge the hand", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2] });
+        state.bigBlind = NaN;
+        state.smallBlind = 1;
+
+        Betting.beginHand(state);
+
+        assert.ok(Number.isFinite(state.currentBet), "the bet to match is still a number");
+        assert.ok(!Number.isNaN(Betting.potSoFar(state)));
+    });
+
+    test("blinds nobody can cover put those players all-in and move on", () => {
+        const state = makeTable({ seatCount: 4, seated: [0, 1, 2], stack: 10 });
+        state.smallBlind = 500;
+        state.bigBlind = 1000;
+        const before = chipsOnTable(state);
+
+        Betting.beginHand(state);
+
+        assert.equal(chipsOnTable(state), before, "no chips invented covering a blind");
+        state.seats.forEach(p => assert.ok((Number(p.stack) || 0) >= 0));
+        assert.ok(state.actingSeatIndex === null || state.seats[state.actingSeatIndex].inHand);
+    });
+});
+
+describe("a saved table that comes back damaged", () => {
+    test("unreadable storage falls back to a fresh table", () => {
+        // load() has to survive whatever is in localStorage, because the alternative
+        // is a dealer opening the tool mid-session to a blank screen.
+        const original = globalThis.localStorage;
+        globalThis.localStorage = {
+            getItem: () => "{not json at all",
+            setItem: () => {},
+            removeItem: () => {},
+        };
+        const state = HoldemState.load();
+        globalThis.localStorage = original;
+
+        assert.equal(state.seats.length, HoldemState.DEFAULT_SEAT_COUNT);
+        assert.equal(state.handNumber, 1);
+    });
+
+    test("a save missing its seats is treated as no save at all", () => {
+        const original = globalThis.localStorage;
+        globalThis.localStorage = {
+            getItem: () => JSON.stringify({ handNumber: 7, smallBlind: 3 }),
+            setItem: () => {},
+            removeItem: () => {},
+        };
+        const state = HoldemState.load();
+        globalThis.localStorage = original;
+
+        assert.ok(Array.isArray(state.seats) && state.seats.length > 0);
+    });
+
+    test("a save from before a field existed gets the field, not undefined", () => {
+        const original = globalThis.localStorage;
+        globalThis.localStorage = {
+            getItem: () => JSON.stringify({
+                seats: [{ id: "a", name: "Ann", inHand: true }, { id: "b", name: "Ben", inHand: true }],
+                handNumber: 4,
+            }),
+            setItem: () => {},
+            removeItem: () => {},
+        };
+        const state = HoldemState.load();
+        globalThis.localStorage = original;
+
+        assert.equal(state.blindOverride, null);
+        assert.equal(state.street, "preflop");
+        state.seats.forEach(p => {
+            assert.equal(p.committed, 0);
+            assert.equal(p.hasActed, false);
+            assert.equal(p.buyIns, 0);
+        });
+        // And it has to be playable, not just parseable.
+        assert.doesNotThrow(() => Betting.beginHand(state));
+    });
+
+    test("storage that refuses to be written doesn't take the table down", () => {
+        const original = globalThis.localStorage;
+        globalThis.localStorage = {
+            getItem: () => null,
+            setItem: () => { throw new Error("QuotaExceededError"); },
+            removeItem: () => {},
+        };
+        const state = HoldemState.createDefault();
+        assert.doesNotThrow(() => HoldemState.save(state), "a full disk must not break the hand in progress");
+        globalThis.localStorage = original;
+    });
+});

tests/holdem/runUiAudit.js

@@ -0,0 +1,134 @@
+// Drives uiAudit.js over the dealer's surfaces at every viewport worth caring about.
+//
+//   node tests/holdem/runUiAudit.js [baseUrl]
+//
+// Needs Playwright available (`npx playwright install chromium` once). It is
+// deliberately NOT wired into the unit-test suite or CI, because that suite is
+// dependency-free and runs in a second — this one needs a browser and a running
+// site. Run it after any change that adds or resizes a control.
+//
+// No Playwright to hand? Open the page, paste tests/holdem/uiAudit.js into devtools,
+// and call LayoutAudit.runAll(). Same checks, one viewport.
+const path = require("path");
+
+const BASE = process.argv[2] || "http://localhost:5299";
+const AUDIT = path.join(__dirname, "uiAudit.js");
+
+// Portrait phones, tablets, desktops, then the same phones on their side — landscape
+// is where this layout has broken most often, because the table is sized from width
+// and the action bar is fixed to a very short viewport.
+const VIEWPORTS = [
+    [360, 640, "Galaxy S8"], [375, 667, "iPhone SE"], [390, 844, "iPhone 14"],
+    [412, 915, "Pixel 7"], [430, 932, "iPhone Pro Max"],
+    [768, 1024, "iPad"], [834, 1112, "iPad Air"], [1024, 1366, "iPad Pro"],
+    [1280, 900, "desktop"], [1600, 1000, "wide desktop"],
+    [640, 360, "S8 landscape"], [667, 375, "SE landscape"], [844, 390, "iPhone landscape"],
+];
+
+const OVERLAYS = [
+    ["rulings", () => document.getElementById("openRulingsBtn").click()],
+    ["seat menu", () => SeatMenu.open(HoldemState.load(), {}, 0)],
+    ["card picker", () => { document.getElementById("cardPickerOverlay").hidden = false; }],
+    ["add chips", () => AddChips.open(HoldemState.load(), 0, () => {})],
+    ["pot wizard", () => document.getElementById("resolvePotBtn").click()],
+];
+
+// A table part-way through a real night: long names, uneven stacks, a hand log.
+function seedTable() {
+    const state = HoldemState.createDefault();
+    HoldemState.resizeSeats(state, 9);
+    [["Christopher", 1200], ["Mike from work", 800], ["Alexandra", 1500], ["Bob", 250], ["Dee", 600]]
+        .forEach(([name, cash], i) => {
+            state.seats[i].name = name;
+            state.seats[i].inHand = true;
+            state.seats[i].buyIns = cash;
+            state.seats[i].stack = cash;
+        });
+    state.smallBlind = 5;
+    state.bigBlind = 10;
+    for (let hand = 1; hand <= 4; hand++) {
+        state.handHistory.push({
+            handNumber: hand, timestamp: Date.now(), pot: 120,
+            payouts: [{ id: state.seats[hand % 5].id, label: "P", amount: 120 }],
+            ledger: state.seats.slice(0, 5).map(p => ({ id: p.id, name: p.name, in: 30, won: 0 })),
+        });
+    }
+    state.handNumber = 5;
+    HoldemState.save(state);
+}
+
+async function main() {
+    let chromium;
+    try {
+        ({ chromium } = require("playwright"));
+    } catch {
+        console.error("This script needs Playwright: npm i -D playwright && npx playwright install chromium");
+        console.error("Or paste tests/holdem/uiAudit.js into devtools and call LayoutAudit.runAll().");
+        process.exit(2);
+    }
+
+    const browser = await chromium.launch();
+    const page = await browser.newPage();
+    const failures = [];
+    const warnings = [];
+    let checks = 0;
+
+    for (const [width, height, label] of VIEWPORTS) {
+        await page.setViewportSize({ width, height });
+
+        await page.goto(`${BASE}/Casino/TexasHoldem`);
+        await page.evaluate(seedTable);
+        await page.goto(`${BASE}/Casino/TexasHoldem`);
+        await page.click("#nextHandBtn");
+        await page.waitForTimeout(300);
+        await page.evaluate(() => document.querySelectorAll("details.sidebarPanel").forEach(d => { d.open = true; }));
+        await page.addScriptTag({ path: AUDIT });
+
+        const table = await page.evaluate(() => LayoutAudit.runAll());
+        checks++;
+        if (!table.clean) failures.push({ where: `table · ${label} ${width}x${height}`, offenders: table.failed.flatMap(f => f.offenders) });
+        table.warnings.forEach(w => warnings.push(`${label}: ${w}`));
+
+        for (const [name, open] of OVERLAYS) {
+            await page.evaluate(open);
+            await page.waitForTimeout(180);
+            checks++;
+            const result = await page.evaluate(() => {
+                const overlay = [...document.querySelectorAll("[id$='Overlay']")].find(o => !o.hidden);
+                if (!overlay) return { offenders: [] };
+                return LayoutAudit.occlusion(`#${overlay.id} button, #${overlay.id} a, #${overlay.id} input`);
+            });
+            await page.evaluate(() => document.querySelectorAll("[id$='Overlay']").forEach(o => { o.hidden = true; }));
+            if (result.offenders.length) failures.push({ where: `${name} · ${label} ${width}x${height}`, offenders: result.offenders });
+        }
+    }
+
+    for (const [width, height, label] of VIEWPORTS.filter((_, i) => i % 4 === 0)) {
+        await page.setViewportSize({ width, height });
+        await page.goto(`${BASE}/Casino/TexasHoldem/QuickSplit`);
+        await page.evaluate(() => {
+            const button = [...document.querySelectorAll("button")].find(b => /all.?in/i.test(b.textContent));
+            if (button) button.click();
+        });
+        await page.addScriptTag({ path: AUDIT });
+        checks++;
+        const result = await page.evaluate(() => LayoutAudit.runAll({ occlusionSelector: "main button, main a, main input" }));
+        if (!result.clean) failures.push({ where: `quick split · ${label} ${width}x${height}`, offenders: result.failed.flatMap(f => f.offenders) });
+    }
+
+    await browser.close();
+
+    console.log(`${checks} audits across ${VIEWPORTS.length} viewports`);
+    warnings.forEach(w => console.log(`  note: ${w}`));
+    if (failures.length === 0) {
+        console.log("clean");
+        return;
+    }
+    failures.forEach(f => {
+        console.log(`\nFAIL ${f.where}`);
+        f.offenders.forEach(o => console.log(`  ${o}`));
+    });
+    process.exit(1);
+}
+
+main();

tests/holdem/selectsOnFocus.test.js

@@ -0,0 +1,53 @@
+// Which fields replace their contents when a dealer reaches for them.
+const test = require("node:test");
+const assert = require("node:assert");
+const { Money } = require("./load");
+
+// Enough of an input to answer the question, without a DOM.
+const field = (props = {}) => ({ tagName: "INPUT", type: "text", inputMode: "", ...props });
+
+test("a number box selects", () => {
+    assert.equal(Money.selectsOnFocus(field({ type: "number" })), true);
+});
+
+test("a decimal keypad box selects", () => {
+    // The raise pad's amount is type=text with inputmode=decimal, so the phone shows
+    // a number pad without the browser's spinner arrows.
+    assert.equal(Money.selectsOnFocus(field({ type: "text", inputMode: "decimal" })), true);
+});
+
+test("a name does not", () => {
+    // Selecting all of a name on focus is the same mistake pointing the other way:
+    // a name is a thing you edit, not a suggestion you replace.
+    assert.equal(Money.selectsOnFocus(field({ type: "text" })), false);
+});
+
+test("a colour swatch does not", () => {
+    assert.equal(Money.selectsOnFocus(field({ type: "color" })), false);
+});
+
+test("a checkbox does not", () => {
+    assert.equal(Money.selectsOnFocus(field({ type: "checkbox" })), false);
+});
+
+test("a textarea does not, whatever it is asked", () => {
+    assert.equal(Money.selectsOnFocus({ tagName: "TEXTAREA", type: "text", inputMode: "decimal" }), false);
+});
+
+test("a select does not", () => {
+    assert.equal(Money.selectsOnFocus({ tagName: "SELECT", type: "select-one" }), false);
+});
+
+test("case doesn't matter", () => {
+    assert.equal(Money.selectsOnFocus(field({ type: "NUMBER" })), true);
+    assert.equal(Money.selectsOnFocus(field({ type: "TEXT", inputMode: "DECIMAL" })), true);
+});
+
+test("nothing at all is not a field", () => {
+    assert.equal(Money.selectsOnFocus(null), false);
+    assert.equal(Money.selectsOnFocus(undefined), false);
+});
+
+test("a field with no type stated is a text box, so it does not", () => {
+    assert.equal(Money.selectsOnFocus({ tagName: "INPUT" }), false);
+});

tests/holdem/settleUp.test.js

@@ -0,0 +1,124 @@
+// Turning the standings into "who hands cash to whom".
+const test = require("node:test");
+const assert = require("node:assert");
+const { Money, HoldemState, SettleUp, makeTable } = require("./load");
+
+const standings = pairs => pairs.map(([name, cashPosition]) => ({ name, cashPosition }));
+const lines = plan => plan.payments.map(p => `${p.from} -> ${p.to} ${Money.format(p.amount)}`);
+const paidTo = (plan, name) =>
+    plan.payments.filter(p => p.to === name).reduce((sum, p) => sum + p.amount, 0);
+const paidBy = (plan, name) =>
+    plan.payments.filter(p => p.from === name).reduce((sum, p) => sum + p.amount, 0);
+
+test("one loser, one winner", () => {
+    const plan = SettleUp.plan(standings([["Ann", 40], ["Ben", -40]]));
+    assert.deepEqual(lines(plan), ["Ben -> Ann $40"]);
+    assert.equal(plan.balanced, true);
+});
+
+test("everybody flat means nothing to do", () => {
+    const plan = SettleUp.plan(standings([["Ann", 0], ["Ben", 0]]));
+    assert.deepEqual(plan.payments, []);
+    assert.equal(plan.balanced, true);
+});
+
+test("nobody at all means nothing to do", () => {
+    const plan = SettleUp.plan([]);
+    assert.deepEqual(plan.payments, []);
+    assert.equal(plan.balanced, true);
+});
+
+test("each player ends up square", () => {
+    const table = standings([
+        ["Ann", 120], ["Ben", -75], ["Cal", -60], ["Dee", 30], ["Eve", -15],
+    ]);
+    const plan = SettleUp.plan(table);
+
+    table.forEach(row => {
+        const settled = paidTo(plan, row.name) - paidBy(plan, row.name);
+        assert.equal(settled, row.cashPosition, `${row.name} should end up square`);
+    });
+    assert.equal(plan.balanced, true);
+});
+
+test("at most one payment fewer than there are people", () => {
+    const table = standings([
+        ["Ann", 120], ["Ben", -75], ["Cal", -60], ["Dee", 30], ["Eve", -15],
+    ]);
+    const plan = SettleUp.plan(table);
+    assert.ok(plan.payments.length <= table.length - 1,
+        `${plan.payments.length} payments for ${table.length} players`);
+});
+
+test("a player who owes two people has both lines together", () => {
+    // The list gets read out one player at a time, so a payer's obligations must not
+    // be split up by somebody else's.
+    const plan = SettleUp.plan(standings([["Ann", 50], ["Cal", 30], ["Ben", -80]]));
+    assert.deepEqual(lines(plan), ["Ben -> Ann $50", "Ben -> Cal $30"]);
+});
+
+test("cents survive", () => {
+    const plan = SettleUp.plan(standings([["Ann", 0.1], ["Ben", 0.2], ["Cal", -0.3]]));
+    assert.deepEqual(lines(plan), ["Cal -> Ben $0.20", "Cal -> Ann $0.10"]);
+    assert.equal(plan.balanced, true);
+});
+
+test("more chips than cash leaves somebody unpaid, and says so", () => {
+    // The table is $25 up on the bank — an unrecorded rebuy or a miscount. The winners
+    // cannot all be paid, and pretending otherwise is how a real person ends up short.
+    const plan = SettleUp.plan(standings([["Ann", 100], ["Ben", -75]]));
+    assert.deepEqual(lines(plan), ["Ben -> Ann $75"]);
+    assert.equal(plan.shortBy, 25);
+    assert.equal(plan.overBy, 0);
+    assert.equal(plan.balanced, false);
+});
+
+test("less chips than cash leaves a payer with nowhere to send it", () => {
+    const plan = SettleUp.plan(standings([["Ann", 50], ["Ben", -75]]));
+    assert.deepEqual(lines(plan), ["Ben -> Ann $50"]);
+    assert.equal(plan.overBy, 25);
+    assert.equal(plan.shortBy, 0);
+    assert.equal(plan.balanced, false);
+});
+
+test("no payment is ever for nothing", () => {
+    const plan = SettleUp.plan(standings([
+        ["Ann", 60], ["Ben", -60], ["Cal", 0], ["Dee", 0],
+    ]));
+    assert.ok(plan.payments.every(p => p.amount > 0));
+    assert.equal(plan.payments.length, 1);
+});
+
+test("nobody pays themselves", () => {
+    const plan = SettleUp.plan(standings([
+        ["Ann", 90], ["Ben", -30], ["Cal", -30], ["Dee", -30],
+    ]));
+    assert.ok(plan.payments.every(p => p.from !== p.to));
+});
+
+test("the payments total what the winners are owed", () => {
+    const table = standings([["Ann", 42.5], ["Ben", 17.5], ["Cal", -60]]);
+    const plan = SettleUp.plan(table);
+    const moved = plan.payments.reduce((sum, p) => sum + p.amount, 0);
+    assert.equal(Money.round(moved), 60);
+});
+
+test("it settles a real table's standings, not just hand-made numbers", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.seats[0].buyIns = 100;
+    state.seats[1].buyIns = 100;
+    state.seats[2].buyIns = 100;
+    state.seats[0].stack = 175;
+    state.seats[1].stack = 90;
+    state.seats[2].stack = 35;
+
+    const rows = HoldemState.sessionStandings(state);
+    const plan = SettleUp.plan(rows);
+
+    // Bank balances — 300 in, 300 on the table — so everyone can be paid.
+    assert.equal(HoldemState.bankReconciliation(state).balanced, true);
+    assert.equal(plan.balanced, true);
+    rows.forEach(row => {
+        assert.equal(paidTo(plan, row.name) - paidBy(plan, row.name), row.cashPosition);
+    });
+});

tests/holdem/shortcuts.test.js

@@ -0,0 +1,110 @@
+// The keyboard shortcuts, and the one rule that keeps them from stealing a press.
+//
+// Shortcuts talks to `document` directly, so these tests stand a small fake one up
+// rather than a whole DOM: the only things it asks about are what has focus and
+// whether an overlay is open.
+const test = require("node:test");
+const assert = require("node:assert");
+const path = require("path");
+
+const Shortcuts = require(path.join(
+    __dirname, "..", "..", "JoshHeaps.Net", "wwwroot", "js", "casino", "holdem", "shortcuts.js"));
+
+// A stand-in for a focused element. `matches` answers the same selector list the
+// real one would, which is the whole of what focusedControlOwnsKey looks at.
+function element(tagName, { selectors = [], isContentEditable = false } = {}) {
+    return {
+        tagName,
+        isContentEditable,
+        matches: selector => selectors.some(s => selector.includes(s)),
+    };
+}
+
+const BUTTON = element("BUTTON", { selectors: ["button"] });
+const SUMMARY = element("SUMMARY", { selectors: ["summary"] });
+const LINK = element("A", { selectors: ["a[href]"] });
+const DIV = element("DIV");
+const TEXT_FIELD = element("INPUT");
+
+// Runs one keypress against a fresh Shortcuts and reports which action fired.
+function press(key, { focused = DIV, overlays = [] } = {}) {
+    const fired = [];
+    let defaultPrevented = false;
+
+    globalThis.document = {
+        activeElement: focused,
+        addEventListener() {},
+        querySelectorAll: () => overlays,
+    };
+
+    const handlers = {};
+    for (const action of Object.values(Shortcuts.KEYS)) {
+        handlers[action] = () => { fired.push(action); return true; };
+    }
+    Shortcuts.handlers = handlers;
+    Shortcuts.onKey({ key, preventDefault: () => { defaultPrevented = true; } });
+
+    return { fired: fired[0] || null, defaultPrevented };
+}
+
+test.after(() => { delete globalThis.document; });
+
+test("Enter on a focused button is left to the button", () => {
+    assert.equal(press("Enter", { focused: BUTTON }).fired, null);
+});
+
+test("Space on a focused button is left to the button", () => {
+    assert.equal(press(" ", { focused: BUTTON }).fired, null);
+});
+
+test("a key left to the control is not swallowed either", () => {
+    // preventDefault would stop the browser activating the button, which is the
+    // half of the bug that turned "wrong action" into "no action".
+    assert.equal(press("Enter", { focused: BUTTON }).defaultPrevented, false);
+});
+
+test("summary and links own Enter and Space too", () => {
+    assert.equal(press("Enter", { focused: SUMMARY }).fired, null);
+    assert.equal(press(" ", { focused: LINK }).fired, null);
+});
+
+test("Space still advances when nothing pressable has focus", () => {
+    assert.equal(press(" ", { focused: DIV }).fired, "advance");
+});
+
+test("Enter still advances when nothing pressable has focus", () => {
+    assert.equal(press("Enter", { focused: DIV }).fired, "advance");
+});
+
+test("the letter shortcuts stay live with a button focused", () => {
+    // A button does nothing with "f", so there is no press to hand back — and a
+    // dealer whose hand is on the keys shouldn't lose them to a stray focus ring.
+    assert.equal(press("f", { focused: BUTTON }).fired, "fold");
+    assert.equal(press("c", { focused: BUTTON }).fired, "checkOrCall");
+    assert.equal(press("r", { focused: BUTTON }).fired, "raise");
+    assert.equal(press("a", { focused: BUTTON }).fired, "allIn");
+    assert.equal(press("u", { focused: BUTTON }).fired, "undo");
+});
+
+test("typing still silences everything but Escape", () => {
+    assert.equal(press("f", { focused: TEXT_FIELD }).fired, null);
+    assert.equal(press("Escape", { focused: TEXT_FIELD }).fired, "cancel");
+});
+
+test("an open overlay still owns the keyboard", () => {
+    assert.equal(press("f", { focused: DIV, overlays: [{ hidden: false }] }).fired, null);
+    assert.equal(press("f", { focused: DIV, overlays: [{ hidden: true }] }).fired, "fold");
+});
+
+test("a focused control wins before the overlay check, not after", () => {
+    // Both would decline here; the point is that neither path fires an action.
+    assert.equal(press("Enter", { focused: BUTTON, overlays: [{ hidden: false }] }).fired, null);
+});
+
+test("modified keys are never shortcuts", () => {
+    globalThis.document = { activeElement: DIV, addEventListener() {}, querySelectorAll: () => [] };
+    const fired = [];
+    Shortcuts.handlers = { advance: () => { fired.push("advance"); return true; } };
+    Shortcuts.onKey({ key: " ", ctrlKey: true, preventDefault() {} });
+    assert.deepEqual(fired, []);
+});

tests/holdem/splitCalculator.test.js

@@ -0,0 +1,65 @@
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { SplitCalculator, Money } = require("./load");
+
+describe("SplitCalculator.split", () => {
+    test("an even chop hands everyone the same stack", () => {
+        const result = SplitCalculator.split(90, 3, 1);
+        assert.equal(result.each, 30);
+        assert.equal(result.oddChips, 0);
+        assert.equal(result.dust, 0);
+        assert.equal(SplitCalculator.accountedFor(result), 90);
+    });
+
+    test("what won't divide is called out as odd chips, not rolled into a stack", () => {
+        // $100 three ways in $5 chips: 20 chips, 6 each, 2 left over.
+        const result = SplitCalculator.split(100, 3, 5);
+        assert.equal(result.each, 30);
+        assert.equal(result.oddChips, 2);
+        assert.equal(SplitCalculator.accountedFor(result), 100);
+    });
+
+    test("a pot that isn't a whole number of chips surfaces the remainder", () => {
+        // $47 in $5 chips: 9 chips ($45) and $2 that no chip in play can pay.
+        const result = SplitCalculator.split(47, 2, 5);
+        assert.equal(result.dust, 2, "the dealer picked a denomination the pot can't make");
+        assert.equal(SplitCalculator.accountedFor(result), 47);
+    });
+
+    test("every split accounts for the whole pot", () => {
+        const chips = [0.25, 0.5, 1, 5, 25, 100];
+        for (let pot = 1; pot <= 400; pot += 7) {
+            for (let ways = 2; ways <= 6; ways++) {
+                chips.forEach(chip => {
+                    const result = SplitCalculator.split(pot, ways, chip);
+                    assert.equal(
+                        Money.toCents(SplitCalculator.accountedFor(result)),
+                        Money.toCents(pot),
+                        `${pot} split ${ways} ways in ${chip} chips lost money`
+                    );
+                });
+            }
+        }
+    });
+
+    test("odd chips are always fewer than the number of players", () => {
+        for (let pot = 1; pot <= 200; pot += 3) {
+            for (let ways = 2; ways <= 8; ways++) {
+                const result = SplitCalculator.split(pot, ways, 1);
+                assert.ok(result.oddChips < ways, "a whole extra chip each would have been dealt out");
+            }
+        }
+    });
+
+    test("an empty pot isn't a valid split", () => {
+        assert.equal(SplitCalculator.split(0, 3, 1).valid, false);
+        assert.equal(SplitCalculator.split(-5, 3, 1).valid, false);
+    });
+
+    test("nonsense inputs fall back to something a dealer can read", () => {
+        const result = SplitCalculator.split(50, 0, 0);
+        assert.equal(result.players, 1, "a split has to be at least one way");
+        assert.equal(result.chip, 0.01, "and at least one cent a chip");
+        assert.equal(SplitCalculator.accountedFor(result), 50);
+    });
+});

tests/holdem/state.test.js

@@ -0,0 +1,147 @@
+const { test, describe } = require("node:test");
+const assert = require("node:assert/strict");
+const { HoldemState, makeTable } = require("./load");
+
+describe("HoldemState.advanceButton", () => {
+    test("the button moves to the next player, not the next empty chair", () => {
+        // Four players spread around a ten-seat table: 0, 3, 4, 8.
+        const state = makeTable({ seatCount: 10, seated: [0, 3, 4, 8], dealerSeatIndex: 0 });
+        HoldemState.advanceButton(state);
+        assert.equal(state.dealerSeatIndex, 3, "skips the three empty chairs between");
+        HoldemState.advanceButton(state);
+        assert.equal(state.dealerSeatIndex, 4);
+        HoldemState.advanceButton(state);
+        assert.equal(state.dealerSeatIndex, 8);
+        HoldemState.advanceButton(state);
+        assert.equal(state.dealerSeatIndex, 0, "wraps back round to the first player");
+    });
+
+    test("every player gets the button once per orbit", () => {
+        const seated = [1, 2, 6, 7, 9];
+        const state = makeTable({ seatCount: 12, seated, dealerSeatIndex: 1 });
+        const visited = [];
+        for (let i = 0; i < seated.length; i++) {
+            visited.push(state.dealerSeatIndex);
+            HoldemState.advanceButton(state);
+        }
+        assert.deepEqual(visited.slice().sort((a, b) => a - b), seated);
+    });
+
+    test("it still moves when nobody is dealt in, rather than looking stuck", () => {
+        const state = makeTable({ seatCount: 6, seated: [], dealerSeatIndex: 2 });
+        HoldemState.advanceButton(state);
+        assert.equal(state.dealerSeatIndex, 3);
+    });
+
+    test("counterclockwise play runs the button the other way", () => {
+        const state = makeTable({ seatCount: 6, seated: [0, 2, 4], dealerSeatIndex: 4 });
+        state.direction = "counterclockwise";
+        HoldemState.advanceButton(state);
+        assert.equal(state.dealerSeatIndex, 2);
+    });
+});
+
+describe("HoldemState.getBlindSeats", () => {
+    test("blinds follow the players, not the chairs left of the button", () => {
+        // Seats 1 and 2 are empty, so the blinds belong on 3 and 7.
+        const state = makeTable({ seatCount: 9, seated: [0, 3, 7], dealerSeatIndex: 0 });
+        const { sbIndex, bbIndex, headsUp } = HoldemState.getBlindSeats(state);
+        assert.equal(headsUp, false);
+        assert.equal(sbIndex, 3);
+        assert.equal(bbIndex, 7);
+    });
+
+    test("heads-up, the button posts the small blind", () => {
+        const state = makeTable({ seatCount: 6, seated: [2, 5], dealerSeatIndex: 2 });
+        const { sbIndex, bbIndex, headsUp } = HoldemState.getBlindSeats(state);
+        assert.equal(headsUp, true);
+        assert.equal(sbIndex, 2, "the button is the small blind heads-up");
+        assert.equal(bbIndex, 5);
+    });
+
+    test("heads-up with the button on an empty chair still posts both blinds", () => {
+        const state = makeTable({ seatCount: 6, seated: [1, 4], dealerSeatIndex: 0 });
+        const { sbIndex, bbIndex, headsUp } = HoldemState.getBlindSeats(state);
+        assert.equal(headsUp, true);
+        assert.equal(sbIndex, 1);
+        assert.equal(bbIndex, 4);
+        assert.notEqual(sbIndex, bbIndex, "two blinds never land on one player");
+    });
+
+    test("fewer than two players means no blinds to post", () => {
+        const state = makeTable({ seatCount: 6, seated: [3], dealerSeatIndex: 0 });
+        const { sbIndex, bbIndex } = HoldemState.getBlindSeats(state);
+        assert.equal(sbIndex, null);
+        assert.equal(bbIndex, null);
+    });
+});
+
+describe("HoldemState.sessionStandings", () => {
+    test("a player's cash position counts chips in front plus chips in the pot", () => {
+        const state = makeTable({ seatCount: 3, seated: [0, 1, 2], stack: 0 });
+        const [a] = state.seats;
+        a.buyIns = 100;
+        a.stack = 60;
+        a.amountOverride = 25; // banked into the hand in progress
+        a.committed = 15;      // still in front of them on this street
+
+        HoldemState.recordHand(state, [{ id: a.id, label: "P1", amount: 0 }]);
+        const standings = HoldemState.sessionStandings(state);
+        const row = standings.find(s => s.id === a.id);
+
+        // 60 in front + 40 in the pot - 100 bought in = level.
+        assert.equal(row.cashPosition, 0, "money in the pot is still theirs until it's won");
+        assert.equal(row.boughtIn, 100);
+        assert.equal(row.chipsNow, 60);
+    });
+
+    test("hand results accumulate across the session", () => {
+        const state = makeTable({ seatCount: 2, seated: [0, 1], stack: 0 });
+        const [a, b] = state.seats;
+        a.amountOverride = 10;
+        b.amountOverride = 10;
+        HoldemState.recordHand(state, [{ id: a.id, label: "P1", amount: 20 }]);
+
+        a.amountOverride = 5;
+        b.amountOverride = 5;
+        HoldemState.recordHand(state, [{ id: b.id, label: "P2", amount: 10 }]);
+
+        const standings = HoldemState.sessionStandings(state);
+        assert.equal(standings.find(s => s.id === a.id).net, 5);
+        assert.equal(standings.find(s => s.id === b.id).net, -5);
+        assert.equal(state.handNumber, 3, "the counter moved on twice");
+    });
+
+    test("the history is capped so a long session can still be saved", () => {
+        const state = makeTable({ seatCount: 2, seated: [0, 1], stack: 0 });
+        for (let i = 0; i < HoldemState.MAX_HISTORY_ENTRIES + 25; i++) {
+            HoldemState.recordHand(state, [{ id: state.seats[0].id, label: "P1", amount: 1 }]);
+        }
+        assert.equal(state.handHistory.length, HoldemState.MAX_HISTORY_ENTRIES);
+        assert.equal(state.handHistory[0].handNumber, HoldemState.MAX_HISTORY_ENTRIES + 25, "newest first");
+    });
+});
+
+describe("HoldemState.resizeSeats", () => {
+    test("the table is clamped to a size a dealer could actually run", () => {
+        const state = makeTable({ seatCount: 6 });
+        HoldemState.resizeSeats(state, 100);
+        assert.equal(state.seatCount, 24);
+        HoldemState.resizeSeats(state, 1);
+        assert.equal(state.seatCount, 2);
+    });
+
+    test("an unreadable seat count falls back to a standard table", () => {
+        // Empty or non-numeric input (and zero, which is equally meaningless)
+        // lands on the default rather than a two-seat table.
+        const state = makeTable({ seatCount: 6 });
+        HoldemState.resizeSeats(state, NaN);
+        assert.equal(state.seatCount, HoldemState.DEFAULT_SEAT_COUNT);
+    });
+
+    test("shrinking past the button brings it back onto the table", () => {
+        const state = makeTable({ seatCount: 9, dealerSeatIndex: 8 });
+        HoldemState.resizeSeats(state, 4);
+        assert.ok(state.dealerSeatIndex < 4);
+    });
+});

tests/holdem/swapSeats.test.js

@@ -0,0 +1,95 @@
+// Two players changing chairs.
+const test = require("node:test");
+const assert = require("node:assert");
+const { Betting, HoldemState, makeTable, chipsOnTable } = require("./load");
+
+test("the whole seat moves", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    state.seats[0].name = "Ann";
+    state.seats[0].cards = ["AS", "KD"];
+    state.seats[0].stack = 175;
+    state.seats[4].name = "";
+
+    HoldemState.swapSeats(state, 0, 4);
+
+    assert.equal(state.seats[4].name, "Ann");
+    assert.deepEqual(state.seats[4].cards, ["AS", "KD"]);
+    assert.equal(state.seats[4].stack, 175);
+    assert.equal(state.seats[0].name, "");
+});
+
+test("what they have in the pot goes with them", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100 });
+    Betting.beginHand(state);
+    const posted = state.seats.map(p => p.committed);
+    const before = chipsOnTable(state);
+
+    HoldemState.swapSeats(state, 1, 4);
+
+    assert.equal(state.seats[4].committed, posted[1]);
+    assert.equal(state.seats[1].committed, posted[4]);
+    assert.equal(chipsOnTable(state), before, "a swap never creates or destroys a chip");
+});
+
+test("the button stays on the chair, not on the player", () => {
+    // A card room moves the button around the table, not around the people. Somebody
+    // who sits down in the big blind's chair is the big blind.
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100, dealerSeatIndex: 0 });
+    state.seats[0].name = "Ann";
+
+    HoldemState.swapSeats(state, 0, 2);
+
+    assert.equal(state.dealerSeatIndex, 0);
+    assert.notEqual(state.seats[0].name, "Ann");
+});
+
+test("the blinds follow the chairs too", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100, dealerSeatIndex: 0 });
+    Betting.beginHand(state);
+    const before = HoldemState.getBlindSeats(state);
+
+    HoldemState.swapSeats(state, before.sbIndex, before.bbIndex);
+    const after = HoldemState.getBlindSeats(state);
+
+    assert.equal(after.sbIndex, before.sbIndex);
+    assert.equal(after.bbIndex, before.bbIndex);
+});
+
+test("swapping a seat with itself does nothing and says so", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1], stack: 100 });
+    const before = JSON.stringify(state);
+
+    assert.equal(HoldemState.swapSeats(state, 1, 1), false);
+    assert.equal(JSON.stringify(state), before);
+});
+
+test("a chair that isn't there is refused rather than swallowed", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1], stack: 100 });
+    const before = JSON.stringify(state);
+
+    assert.equal(HoldemState.swapSeats(state, 0, 99), false);
+    assert.equal(HoldemState.swapSeats(state, -1, 0), false);
+    assert.equal(JSON.stringify(state), before);
+});
+
+test("swapping twice puts everything back", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100 });
+    Betting.beginHand(state);
+    const before = JSON.stringify(state);
+
+    HoldemState.swapSeats(state, 1, 3);
+    HoldemState.swapSeats(state, 1, 3);
+
+    assert.equal(JSON.stringify(state), before);
+});
+
+test("moving into an empty chair leaves an empty chair behind", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1], stack: 100 });
+    state.seats[1].name = "Ben";
+
+    HoldemState.swapSeats(state, 1, 5);
+
+    assert.equal(state.seats[5].name, "Ben");
+    assert.equal(state.seats[5].inHand, true);
+    assert.equal(state.seats[1].inHand, false);
+});

tests/holdem/uiAudit.js

@@ -0,0 +1,582 @@
+// Layout and touch audits for the dealer, written once so they stop being written
+// again every round.
+//
+// These checks have been re-typed into a browser console at least six times over
+// the course of building this thing, and each time they only covered whatever had
+// just been changed. That is exactly how the standings table shipped with a
+// zero-pixel player-name column and survived two rounds: the audit that would have
+// caught it existed only in a previous session's scrollback.
+//
+// This file is deliberately dependency-free and browser-side. It is injected into
+// the page (see runUiAudit.js) rather than imported, so it needs no build step, no
+// package.json, and no browser automation of its own — anyone can also paste it
+// into devtools and call LayoutAudit.runAll().
+const LayoutAudit = {
+    // Everything a dealer has to be able to hit.
+    CONTROL_SELECTOR: "button, a, input, select, textarea, [role='button'], .seat",
+
+    describe(el) {
+        if (!el) return "(nothing)";
+        const id = el.id ? `#${el.id}` : "";
+        const cls = (el.className || "").toString().trim().split(/\s+/).filter(Boolean).slice(0, 2).join(".");
+        const text = (el.textContent || "").replace(/\s+/g, " ").trim().slice(0, 24);
+        return `${el.tagName.toLowerCase()}${id}${cls ? "." + cls : ""}${text ? ` "${text}"` : ""}`;
+    },
+
+    visibleControls() {
+        return [...document.querySelectorAll(this.CONTROL_SELECTOR)].filter(el => {
+            const rect = el.getBoundingClientRect();
+            if (rect.width === 0 || rect.height === 0) return false;
+            const style = getComputedStyle(el);
+            return style.visibility !== "hidden" && style.display !== "none";
+        });
+    },
+
+    // ---- Touch (see the mobile round) ----
+
+    // Without touch-action: manipulation a mobile browser holds every tap for ~300ms
+    // deciding whether it was a double-tap-to-zoom. This tool uses double-tap on a
+    // seat as its fold shortcut, so that wait is on the critical path.
+    touchAction() {
+        const offenders = this.visibleControls()
+            .filter(el => getComputedStyle(el).touchAction === "auto")
+            .map(el => this.describe(el));
+        return { name: "touch-action", offenders, checked: this.visibleControls().length };
+    },
+
+    tapHighlight() {
+        const offenders = this.visibleControls()
+            .filter(el => {
+                const colour = getComputedStyle(el).webkitTapHighlightColor;
+                return colour && !/rgba\(0,\s*0,\s*0,\s*0\)|transparent/.test(colour);
+            })
+            .map(el => this.describe(el));
+        return { name: "tap-highlight", offenders, checked: this.visibleControls().length };
+    },
+
+    // Text selection must stay ON for anything a dealer types into.
+    textSelectable() {
+        const offenders = [...document.querySelectorAll("input[type='text'], input[type='number'], textarea")]
+            .filter(el => el.offsetParent !== null)
+            .filter(el => {
+                const style = getComputedStyle(el);
+                return (style.webkitUserSelect || style.userSelect) === "none";
+            })
+            .map(el => this.describe(el));
+        return { name: "fields stay selectable", offenders };
+    },
+
+    // ---- Reachability (see the occlusion round) ----
+
+    // A control covered by something else is unreachable however good it looks.
+    // Sampling several points matters: a button you can only hit in one corner is
+    // covered for practical purposes.
+    // Can this element be brought into view by scrolling? Something below the fold on
+    // a page that scrolls is perfectly reachable; something below the fold in a panel
+    // that *doesn't* scroll is lost. The first version of this check didn't make the
+    // distinction and reported every link under the fold as a fault.
+    reachableByScrolling(el) {
+        const rect = el.getBoundingClientRect();
+        if (getComputedStyle(el).position === "fixed") return false;
+
+        for (let node = el.parentElement; node; node = node.parentElement) {
+            const style = getComputedStyle(node);
+            const scrolls = /auto|scroll|overlay/.test(style.overflowY) || node === document.body;
+            if (!scrolls) continue;
+            const box = node === document.body ? { top: 0, bottom: innerHeight } : node.getBoundingClientRect();
+            const room = node === document.body
+                ? document.documentElement.scrollHeight - innerHeight - scrollY
+                : node.scrollHeight - node.clientHeight - node.scrollTop;
+            if (rect.top >= box.bottom && room > 0) return true;
+            if (rect.bottom <= box.top && (node === document.body ? scrollY > 0 : node.scrollTop > 0)) return true;
+        }
+        return false;
+    },
+
+    occlusion(selector = "#actionBar button, #holdemHeader button, .seat") {
+        const offenders = [];
+        const warnings = [];
+        [...document.querySelectorAll(selector)].forEach(el => {
+            const rect = el.getBoundingClientRect();
+            if (rect.width === 0 || rect.height === 0) return;
+
+            const outsideViewport = rect.bottom <= 0 || rect.top >= innerHeight ||
+                                    rect.right <= 0 || rect.left >= innerWidth;
+            if (outsideViewport) {
+                if (!this.reachableByScrolling(el)) {
+                    offenders.push(`${this.describe(el)} :: off-screen and cannot be scrolled to`);
+                }
+                return;
+            }
+
+            const points = [
+                [rect.left + rect.width / 2, rect.top + rect.height / 2],
+                [rect.left + rect.width * 0.25, rect.top + rect.height * 0.3],
+                [rect.left + rect.width * 0.75, rect.top + rect.height * 0.3],
+                [rect.left + rect.width * 0.25, rect.top + rect.height * 0.7],
+                [rect.left + rect.width * 0.75, rect.top + rect.height * 0.7],
+            ].filter(([x, y]) => x >= 0 && y >= 0 && x < innerWidth && y < innerHeight);
+            if (points.length === 0) return;
+
+            let blocked = 0;
+            let testable = 0;
+            let blockedBy = null;
+            points.forEach(([x, y]) => {
+                const top = document.elementFromPoint(x, y);
+                // A null result means the point isn't hit-testable — typically it sits
+                // inside the element but outside a scrollable ancestor's clip, i.e. the
+                // control is scrolled out of view rather than covered by anything.
+                // Counting that as "covered by null" was reporting a perfectly
+                // reachable button in a sheet that scrolls.
+                if (!top) return;
+                testable++;
+                if (el.contains(top) || top === el || top.contains(el)) return;
+                // Seats ring a round table and overlap each other at the rim by
+                // design; that is crowding, not an overlay hiding a control.
+                //
+                // But only the seat's *body* is harmless. A neighbouring seat's own
+                // controls sitting on top of this one is a control being stolen, and
+                // exempting the whole seat subtree hid exactly that: an enlarged
+                // dealer-chip hit area was taking the centre of the seat three
+                // places round the table, and this check called it crowding and
+                // moved on.
+                const neighbourSeat = top.closest && top.closest(".seat");
+                if (neighbourSeat) {
+                    const isControl = top.matches && top.matches("button, a, input, select, textarea, [role='button']");
+                    if (!isControl) return;
+                }
+                blocked++;
+                if (!blockedBy) blockedBy = this.describe(top);
+            });
+
+            if (testable === 0) {
+                if (!this.reachableByScrolling(el)) {
+                    offenders.push(`${this.describe(el)} :: not hit-testable anywhere and cannot be scrolled to`);
+                }
+                return;
+            }
+            if (blocked === 0) return;
+
+            const note = `${this.describe(el)} :: ${blocked === testable ? "fully" : `${blocked}/${testable}`} covered by ${blockedBy}`;
+
+            // A toast is transient by design: it dismisses itself and carries a close
+            // button, and on a desktop it necessarily lands over a table that fills the
+            // content column. Partial overlap from one is a fact of the layout, not a
+            // fault. Being *fully* covered by a toast is still a failure though — that
+            // was a real bug once, where a seat sat exactly under the Undo button and a
+            // tap meant for a player took back the last action instead.
+            const transient = blockedBy && /toast/i.test(blockedBy);
+            if (transient && blocked < testable) warnings.push(note);
+            else offenders.push(note);
+        });
+        return { name: "nothing important is covered", offenders, warnings };
+    },
+
+    // ---- Layout (the check that would have caught the standings regression) ----
+
+    // A grid column squeezed to nothing doesn't truncate its text, it erases it.
+    // This is the one that was missing: the player-name column sat at 0px through
+    // two rounds because nothing ever asked whether a column had survived.
+    collapsedColumns() {
+        const offenders = [];
+        [...document.querySelectorAll("[class*='Row'], [class*='row']")].forEach(row => {
+            if (getComputedStyle(row).display !== "grid") return;
+            [...row.children].forEach(cell => {
+                if (getComputedStyle(cell).display === "none") return;
+                const hasText = (cell.textContent || "").trim().length > 0;
+                if (hasText && cell.getBoundingClientRect().width < 4) {
+                    offenders.push(`${this.describe(row)} > ${this.describe(cell)} :: ${Math.round(cell.getBoundingClientRect().width)}px wide`);
+                }
+            });
+        });
+        return { name: "no column collapsed to nothing", offenders };
+    },
+
+    // Text actually painted outside the box meant to contain it — which on a table of
+    // overlapping seats means painted on top of a neighbour.
+    //
+    // The clipping check is the whole subtlety, and the first version of this got it
+    // wrong. A Range's bounding rect measures the *laid out* text, which happily runs
+    // past the element when `overflow: hidden` is quietly clipping it — so an
+    // ellipsised name was reported as spilling when nothing was drawn outside at all.
+    // Only overflow that is actually visible can paint over a neighbour.
+    textSpill(selector = ".seatPuckStack, .seatPuckTotal, .seatPuckName") {
+        const offenders = [];
+        [...document.querySelectorAll(selector)].forEach(el => {
+            const text = (el.textContent || "").trim();
+            if (!text) return;
+
+            const style = getComputedStyle(el);
+            const clipsItself = style.overflow !== "visible" || style.overflowX !== "visible";
+            if (clipsItself) return;
+
+            const container = el.closest(".seat") || el.parentElement;
+            if (!container) return;
+
+            const range = document.createRange();
+            range.selectNodeContents(el);
+            const drawn = range.getBoundingClientRect();
+            const bounds = container.getBoundingClientRect();
+            if (drawn.left < bounds.left - 1 || drawn.right > bounds.right + 1) {
+                offenders.push(`${this.describe(el)} "${text}" paints outside ${this.describe(container)}`);
+            }
+        });
+        return { name: "no text painted outside its box", offenders };
+    },
+
+    horizontalOverflow() {
+        const offenders = document.documentElement.scrollWidth > innerWidth + 1
+            ? [`page scrolls sideways: ${document.documentElement.scrollWidth}px in a ${innerWidth}px viewport`]
+            : [];
+        return { name: "page never scrolls sideways", offenders };
+    },
+
+    // iOS zooms the whole page when a field under 16px takes focus, and the dealer
+    // is then pinching back out mid-hand.
+    fieldFontSize() {
+        const offenders = [...document.querySelectorAll("input, textarea, select")]
+            .filter(el => el.offsetParent !== null)
+            .filter(el => ["text", "number", "search", "tel", "url", "email", "password", ""].includes(el.type || ""))
+            .filter(el => parseFloat(getComputedStyle(el).fontSize) < 16)
+            .map(el => `${this.describe(el)} at ${getComputedStyle(el).fontSize}`);
+        return { name: "no field small enough to trigger iOS zoom", offenders };
+    },
+
+    // ---- Contrast ----
+    //
+    // This check has been got wrong twice before, both times by being too clever about
+    // backgrounds. The first version read only `background-color`, so every sheet
+    // painted with a gradient was measured against transparency and the dealer puck's
+    // dark "D" was reported at 1.2:1 against nothing. The second over-corrected and
+    // treated low-alpha gradient stops as opaque, scoring white-on-dark at 1.0:1.
+    //
+    // So it is built to be incapable of false positives instead of trying to be exact.
+    // Backgrounds composite properly through alpha, and where a gradient is involved
+    // every one of its colour stops is tried and the *most flattering* one is used. A
+    // finding therefore means the text fails even under the reading most generous to
+    // it, which is a claim worth making. Text that can't be resolved to any opaque
+    // background is reported separately as unmeasured rather than guessed at.
+
+    parseColour(value) {
+        const match = String(value).match(/rgba?\(([^)]+)\)/);
+        if (!match) return null;
+        const parts = match[1].split(/[,\s/]+/).filter(Boolean).map(Number);
+        if (parts.length < 3 || parts.some(Number.isNaN)) return null;
+        return { r: parts[0], g: parts[1], b: parts[2], a: parts.length > 3 ? parts[3] : 1 };
+    },
+
+    // Colour stops out of any gradient in a background-image.
+    gradientStops(backgroundImage) {
+        if (!backgroundImage || backgroundImage === "none") return [];
+        return (backgroundImage.match(/rgba?\([^)]+\)/g) || [])
+            .map(c => this.parseColour(c))
+            .filter(Boolean);
+    },
+
+    over(top, bottom) {
+        const a = top.a;
+        return {
+            r: top.r * a + bottom.r * (1 - a),
+            g: top.g * a + bottom.g * (1 - a),
+            b: top.b * a + bottom.b * (1 - a),
+            a: 1,
+        };
+    },
+
+    relativeLuminance({ r, g, b }) {
+        const channel = v => {
+            const s = v / 255;
+            return s <= 0.03928 ? s / 12.92 : Math.pow((s + 0.055) / 1.055, 2.4);
+        };
+        return 0.2126 * channel(r) + 0.7152 * channel(g) + 0.0722 * channel(b);
+    },
+
+    contrastRatio(fg, bg) {
+        const a = this.relativeLuminance(fg);
+        const b = this.relativeLuminance(bg);
+        return (Math.max(a, b) + 0.05) / (Math.min(a, b) + 0.05);
+    },
+
+    // Every background this text could actually be sitting on.
+    //
+    // Layers are collected from the element outwards and stop at the first fully
+    // opaque one, because nothing behind that is visible. Getting this wrong in the
+    // lenient direction is just as bad as the old false positives: an earlier version
+    // kept walking past an opaque gradient and offered the page background as a
+    // candidate, which scored white-on-a-mid-grey-panel as though it were
+    // white-on-near-black and would have waved real problems through.
+    //
+    // A gradient contributes one candidate per colour stop; translucent layers above
+    // the opaque one are composited onto each candidate in order.
+    backgroundCandidates(el) {
+        const translucent = [];   // top-down, above the opaque layer
+        let base = null;          // candidate colours for the first opaque layer
+
+        for (let node = el; node && !base; node = node.parentElement) {
+            const style = getComputedStyle(node);
+            const stops = this.gradientStops(style.backgroundImage);
+            const colour = this.parseColour(style.backgroundColor);
+
+            // A gradient whose stops are all opaque hides everything behind it.
+            if (stops.length > 0 && stops.every(s => s.a === 1)) {
+                base = stops;
+                break;
+            }
+            stops.forEach(s => { if (s.a > 0) translucent.push(s); });
+
+            if (colour && colour.a === 1) { base = [colour]; break; }
+            if (colour && colour.a > 0) translucent.push(colour);
+        }
+
+        if (!base) {
+            // Nothing opaque anywhere up the tree — fall back to the page's own colour
+            // so a finding is still measured against something real.
+            const page = this.parseColour(getComputedStyle(document.documentElement).backgroundColor);
+            base = [page && page.a === 1 ? page : { r: 10, g: 10, b: 10, a: 1 }];
+        }
+
+        // Fold the translucent layers back on, innermost last so it lands on top.
+        return base.map(candidate => {
+            let composed = candidate;
+            for (let i = translucent.length - 1; i >= 0; i--) composed = this.over(translucent[i], composed);
+            return composed;
+        });
+    },
+
+    contrast({ minimum = 4.5, largeMinimum = 3, selector = null } = {}) {
+        const offenders = [];
+        const unmeasured = [];
+
+        const nodes = selector
+            ? [...document.querySelectorAll(selector)]
+            : [...document.querySelectorAll("*")];
+
+        nodes.forEach(el => {
+            if (el.children.length > 0) return;               // leaf text only
+            const text = (el.textContent || "").trim();
+            if (!text) return;
+            const rect = el.getBoundingClientRect();
+            if (rect.width === 0 || rect.height === 0) return;
+            const style = getComputedStyle(el);
+            if (style.visibility === "hidden" || style.display === "none") return;
+            if (parseFloat(style.opacity) < 0.99) return;     // faded on purpose
+            // Decoration is exempt by definition: the watermark on the felt is meant
+            // to be barely there, and holding it to a reading threshold would mean
+            // making it not a watermark. Marked aria-hidden so screen readers skip it
+            // too, which is the same claim expressed where it also does some good.
+            if (el.closest("[aria-hidden='true']")) return;
+
+            const fgRaw = this.parseColour(style.color);
+            if (!fgRaw) return;
+
+            const candidates = this.backgroundCandidates(el);
+            if (candidates.length === 0) {
+                unmeasured.push(`${this.describe(el)} :: no opaque background found`);
+                return;
+            }
+
+            // The kindest reading available: best contrast across every candidate.
+            let best = 0;
+            candidates.forEach(bg => {
+                const fg = fgRaw.a === 1 ? fgRaw : this.over(fgRaw, bg);
+                best = Math.max(best, this.contrastRatio(fg, bg));
+            });
+
+            const sizePx = parseFloat(style.fontSize);
+            const weight = parseInt(style.fontWeight, 10) || 400;
+            const isLarge = sizePx >= 24 || (sizePx >= 18.66 && weight >= 700);
+            const required = isLarge ? largeMinimum : minimum;
+
+            if (best + 0.05 < required) {
+                offenders.push(`${this.describe(el)} :: ${best.toFixed(2)}:1 (needs ${required}:1) at ${Math.round(sizePx)}px`);
+            }
+        });
+
+        return { name: "text meets WCAG AA contrast", offenders, unmeasured };
+    },
+
+    // ---- Reach (touch target sizes) ----
+
+    // What a fingertip can actually hit, which is not the same as the element's box.
+    //
+    // Two things make the box misleading, and the first version of this check was
+    // fooled by both. A control can be padded out with a transparent ::after, so it
+    // responds well beyond its painted size — that's how a 22px dealer puck should
+    // stay 22px and still take a thumb. And a checkbox wrapped in a label is hit by
+    // tapping anywhere on the label, so a 24px box inside a 320x44 label is a
+    // perfectly good target. Measuring the box reported both as faults.
+    //
+    // So it probes outwards with elementFromPoint until the point stops landing on the
+    // control, which is the thing a finger actually experiences.
+    effectiveTarget(el, limit = 48) {
+        const rect = el.getBoundingClientRect();
+        const cx = rect.left + rect.width / 2;
+        const cy = rect.top + rect.height / 2;
+        // The probe walks outward a fixed distance, so it can only ever report
+        // 2 x limit. Anything already drawn larger than that reads as exactly the cap
+        // — which had every header button reporting a suspiciously round 80px. Give
+        // the reach room for the element itself plus the padding being looked for.
+        limit = Math.max(limit, rect.width / 2 + 24, rect.height / 2 + 24);
+
+        // A wrapping or associated label forwards the tap, so it counts as the target.
+        const label = el.closest("label") || (el.labels && el.labels[0]);
+        const lands = (x, y) => {
+            if (x < 0 || y < 0 || x >= innerWidth || y >= innerHeight) return false;
+            const hit = document.elementFromPoint(x, y);
+            if (!hit) return false;
+            if (hit === el || el.contains(hit)) return true;
+            return !!(label && (hit === label || label.contains(hit)));
+        };
+
+        if (!lands(cx, cy)) return null;   // centre isn't even hittable; occlusion's problem
+
+        const reach = (dx, dy) => {
+            let far = 0;
+            for (let d = 1; d <= limit; d++) {
+                if (!lands(cx + dx * d, cy + dy * d)) break;
+                far = d;
+            }
+            return far;
+        };
+        return { width: reach(-1, 0) + reach(1, 0), height: reach(0, -1) + reach(0, 1) };
+    },
+
+    // The 44px guideline is about fingertips, so it only bites where there's no mouse.
+    // Enforcing it everywhere flagged the header buttons at 42px tall on a desktop,
+    // which is not a defect — the same buttons are 64px tall on a phone, where it
+    // matters. Same reasoning as the field sizing: `hover: none` is what actually
+    // distinguishes a finger from a pointer, not viewport width.
+    //
+    // `exempt` is for controls that are deliberately small *and* have a full-size path
+    // to the same action. The dealer puck is the only one: it's a 22px chip sitting on
+    // the rim of a seat, and growing it to 44px would take that area from the seat
+    // itself — which a dealer taps far more often. "Give the button" is in the seat
+    // menu at full size, so the puck is a shortcut, not the only way through.
+    touchTargets(minimum = 44, { exempt = ".dealerChip", enforceOnPointerDevices = false } = {}) {
+        const offenders = [];
+        if (!enforceOnPointerDevices && matchMedia("(hover: hover)").matches) {
+            return { name: `touch targets at least ${minimum}px`, offenders, skipped: "pointer device" };
+        }
+        this.visibleControls()
+            .filter(el => el.type !== "color")
+            .filter(el => !(exempt && el.matches(exempt)))
+            .forEach(el => {
+                const rect = el.getBoundingClientRect();
+                // Drawn big enough is big enough — no need to probe, and probing wide
+                // elements is where the cap above used to produce nonsense. Seats sit
+                // here: they're 76x72 and overlap each other at the rim by design, so
+                // measuring their reach would report the crowding as a fault.
+                if (rect.width >= minimum - 1 && rect.height >= minimum - 1) return;
+
+                const size = this.effectiveTarget(el);
+                if (!size) return;
+                if (size.width >= minimum - 1 && size.height >= minimum - 1) return;
+                offenders.push(
+                    `${this.describe(el)} :: hittable ${size.width}x${size.height}` +
+                    ` (drawn ${Math.round(rect.width)}x${Math.round(rect.height)})`
+                );
+            });
+        return { name: `touch targets at least ${minimum}px`, offenders };
+    },
+
+    // Tapping the middle of a seat must give you that seat.
+    //
+    // Added after a dealer-chip hit area, meant to make a 22px puck thumb-sized, grew
+    // outward from a chip that already hung over its seat's corner — and therefore
+    // over the seat next to it. On a nine-seat table, tapping the centre of seat 1
+    // handed the button to seat 9. The occlusion check missed it because it treated
+    // anything inside a `.seat` as harmless crowding.
+    //
+    // Reported separately from occlusion because the cause is different: not an
+    // overlay on top of the table, but two pieces of the table fighting over a tap.
+    seatOwnership() {
+        const seats = [...document.querySelectorAll(".seat")];
+        const offenders = [];
+
+        seats.forEach((seat, index) => {
+            const rect = seat.getBoundingClientRect();
+            if (rect.width === 0 || rect.height === 0) return;
+            const x = rect.left + rect.width / 2;
+            const y = rect.top + rect.height / 2;
+            if (x < 0 || y < 0 || x >= innerWidth || y >= innerHeight) return;
+
+            const hit = document.elementFromPoint(x, y);
+            if (!hit || seat.contains(hit) || hit === seat) return;
+
+            const other = hit.closest(".seat");
+            const who = other ? `seat ${seats.indexOf(other) + 1}` : this.describe(hit);
+            const control = hit.matches && hit.matches("button, a, input, select, [role='button']");
+            offenders.push(
+                `seat ${index + 1}'s centre goes to ${who}${control ? "'s " + this.describe(hit) : ""}`
+            );
+        });
+
+        return { name: "a seat's centre belongs to that seat", offenders };
+    },
+
+    // A poker table has one dealer button. Nine pucks all showing "D", one of them
+    // gold, turns the most-read marker on the felt into a spot-the-difference — and
+    // a screen reader heard nine buttons named "D" with nothing to tell them apart.
+    // Both halves are checked here: what's drawn, and what it announces itself as.
+    oneDealerButton() {
+        const chips = [...document.querySelectorAll(".dealerChip")];
+        const shown = chips.filter(chip => {
+            const style = getComputedStyle(chip);
+            if (style.display === "none" || style.visibility === "hidden") return false;
+            if (parseFloat(style.opacity) <= 0.05) return false;
+            // A hovered seat deliberately fades its empty slot in — that's the "put the
+            // button here" preview, and it is on screen because a pointer is sitting on
+            // that seat. Counting it reports two buttons whenever the mouse happens to
+            // rest on the table, which is most of the time a mouse exists.
+            const seat = chip.closest(".seat");
+            if (seat && seat.matches(":hover") && !chip.classList.contains("active")) return false;
+            return true;
+        });
+        const offenders = [];
+
+        if (shown.length > 1) {
+            offenders.push(`${shown.length} dealer buttons drawn on the felt at once`);
+        }
+
+        const labels = chips.map(chip => chip.getAttribute("aria-label") || chip.textContent.trim());
+        const duplicated = labels.filter((label, i) => labels.indexOf(label) !== i);
+        if (duplicated.length) {
+            offenders.push(
+                `${duplicated.length + 1} dealer buttons announce themselves as "${duplicated[0]}"`
+            );
+        }
+
+        return { name: "the felt shows one dealer button", offenders };
+    },
+
+    // ---- Runner ----
+
+    runAll(options = {}) {
+        const checks = [
+            this.touchAction(),
+            this.tapHighlight(),
+            this.textSelectable(),
+            this.occlusion(options.occlusionSelector),
+            this.collapsedColumns(),
+            this.textSpill(),
+            this.horizontalOverflow(),
+            this.fieldFontSize(),
+            this.seatOwnership(),
+            this.oneDealerButton(),
+        ];
+        if (options.includeTouchTargets) checks.push(this.touchTargets(options.minimumTarget));
+
+        return {
+            viewport: `${innerWidth}x${innerHeight}`,
+            failed: checks.filter(c => c.offenders.length > 0),
+            // Things worth knowing that aren't faults — see occlusion() on toasts.
+            warnings: checks.flatMap(c => c.warnings || []),
+            passed: checks.filter(c => c.offenders.length === 0).map(c => c.name),
+            clean: checks.every(c => c.offenders.length === 0),
+        };
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = LayoutAudit;
+}

tests/holdem/wagerVerb.test.js

@@ -0,0 +1,83 @@
+// Whether putting more in is called a bet or a raise.
+//
+// The arithmetic was always right — minRaiseTo returns two big blinds for the big
+// blind's option and one for an opening bet. This is only what it's called, which for
+// a tool a dealer announces the action from is not a small thing.
+const test = require("node:test");
+const assert = require("node:assert");
+const { Betting, makeTable } = require("./load");
+
+// Walks the preflop action round to the big blind, who is owed nothing and gets to
+// choose between checking and putting more in.
+function toTheBigBlindsOption() {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100, dealerSeatIndex: 0 });
+    Betting.beginHand(state);
+    const bigBlind = state.seats.findIndex(player => Betting.committed(player) === state.bigBlind);
+    while (state.actingSeatIndex !== null && state.actingSeatIndex !== bigBlind) {
+        Betting.call(state, state.actingSeatIndex);
+    }
+    return { state, bigBlind };
+}
+
+test("the big blind's option is a raise, not a bet", () => {
+    const { state, bigBlind } = toTheBigBlindsOption();
+
+    assert.equal(state.actingSeatIndex, bigBlind);
+    assert.equal(Betting.toCall(state, state.seats[bigBlind]), 0, "they owe nothing");
+    assert.equal(Betting.wagerVerb(state), "raise", "but their own blind is a live bet");
+});
+
+test("and the minimum there is a real raise, not a call of the blind", () => {
+    const { state } = toTheBigBlindsOption();
+    assert.equal(Betting.minRaiseTo(state), state.bigBlind * 2);
+});
+
+test("facing the blinds preflop is a raise", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2, 3], stack: 100 });
+    Betting.beginHand(state);
+    assert.equal(Betting.wagerVerb(state), "raise");
+});
+
+test("first in on the flop is a bet", () => {
+    const { state, bigBlind } = toTheBigBlindsOption();
+    Betting.check(state, bigBlind);
+    Betting.closeStreet(state);
+
+    assert.equal(state.street, "flop");
+    assert.equal(Betting.wagerVerb(state), "bet");
+    assert.equal(Betting.minRaiseTo(state), state.bigBlind, "a first bet is one big blind");
+});
+
+test("after that bet it's a raise again", () => {
+    const { state, bigBlind } = toTheBigBlindsOption();
+    Betting.check(state, bigBlind);
+    Betting.closeStreet(state);
+    Betting.raiseTo(state, state.actingSeatIndex, 10);
+
+    assert.equal(Betting.wagerVerb(state), "raise");
+});
+
+test("and a bet again on the next street once it's checked around", () => {
+    const { state, bigBlind } = toTheBigBlindsOption();
+    Betting.check(state, bigBlind);
+    Betting.closeStreet(state);
+    while (state.actingSeatIndex !== null) Betting.check(state, state.actingSeatIndex);
+    Betting.closeStreet(state);
+
+    assert.equal(state.street, "turn");
+    assert.equal(Betting.wagerVerb(state), "bet");
+});
+
+test("a table playing without blinds opens with a bet", () => {
+    const state = makeTable({ seatCount: 6, seated: [0, 1, 2], stack: 100, smallBlind: 0, bigBlind: 0 });
+    Betting.beginHand(state);
+    assert.equal(state.currentBet, 0);
+    assert.equal(Betting.wagerVerb(state), "bet");
+});
+
+test("asking doesn't change anything", () => {
+    const { state } = toTheBigBlindsOption();
+    const before = JSON.stringify(state);
+    Betting.wagerVerb(state);
+    assert.equal(JSON.stringify(state), before);
+});