Choose color against cpu

JoshHeaps.Net/Controllers/ChessController.cs

@@ -35,7 +35,7 @@ public class ChessController(
     /// </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;
@@ -45,7 +45,12 @@ public class ChessController(
         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);
 

JoshHeaps.Net/Pages/Chess.cshtml

@@ -89,6 +89,15 @@
     </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?v=@ViewData["cssVersion"]"></script>

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

@@ -157,6 +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/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();
     },
 

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/chessMain.js

@@ -91,7 +91,8 @@ async function startCPUGame() {
 
     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();

native/chess_engine/src/chess_engine.cpp

@@ -208,14 +208,32 @@ 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) {
@@ -274,17 +292,6 @@ 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