Merge pull request 'Replace the browser confirm boxes with undo and in-page dialogs' (#17) from feature/casino-holdem-undo-toasts into feature/casino-holdem-mobile-table

Reviewed-on: #17

.gitea/workflows/deploy.yml

@@ -1,4 +1,4 @@
-# .gitea/workflows/deploy.yml
+# .gitea/workflows/deploy.yml
 name: Build and Deploy
 
 on:
@@ -12,13 +12,17 @@ concurrency:
 
 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 deploy tools
+      - name: Install toolchain
         run: |
           apt-get update
-          apt-get install -y --no-install-recommends rsync openssh-client
+          apt-get install -y --no-install-recommends \
+            cmake build-essential rsync openssh-client
 
       - name: Checkout
         uses: actions/checkout@v4
@@ -29,10 +33,26 @@ jobs:
           dotnet-version: '8.0.x'
 
       - name: Restore
-        run: dotnet 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 -c Release -o ./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:
@@ -47,6 +67,8 @@ jobs:
           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:   ${{ secrets.SSH_HOST }}
@@ -56,11 +78,11 @@ jobs:
         run: |
           set -euo pipefail
           PORT="${SSH_PORT:-22}"
-          rsync -az --delete \
+          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: Restart service
+      - name: Reload and restart service
         env:
           SSH_HOST:     ${{ secrets.SSH_HOST }}
           SSH_PORT:     ${{ secrets.SSH_PORT }}

JoshHeaps.Net.UiTests/EchoDspTests.cs

@@ -1,296 +0,0 @@
-using Microsoft.Playwright;
-using Microsoft.Playwright.NUnit;
-using NUnit.Framework;
-
-namespace JoshHeaps.Net.UiTests;
-
-/// <summary>
-/// Exercises the acoustic-ranging pipeline against a simulated room. The DSP runs in the browser
-/// because that is where it runs in production; these tests drive the same files the page loads,
-/// so there is no second implementation to drift.
-/// </summary>
-[TestFixture]
-public class EchoDspTests : PageTest
-{
-    private TestConfiguration Config => TestConfiguration.Instance;
-
-    public override BrowserNewContextOptions ContextOptions() => Config.GetBrowserContextOptions();
-
-    [SetUp]
-    public async Task LoadPipeline()
-    {
-        await Page.GotoAsync(Config.Test.BaseUrl);
-        await Page.AddScriptTagAsync(new() { Url = "/js/EchoScripts/EchoDsp.js" });
-        await Page.AddScriptTagAsync(new() { Url = "/js/EchoScripts/EchoSim.js" });
-    }
-
-    [Test]
-    public async Task Matched_Filter_Finds_The_Chirp_Within_One_Sample()
-    {
-        var error = await Page.EvaluateAsync<double>("""
-            () => {
-                const sampleRate = 48000;
-                const chirp = EchoDsp.makeChirp({ sampleRate, durationSeconds: 0.05, startHz: 2000, endHz: 8000 });
-                const recording = new Float32Array(sampleRate);
-                for (let i = 0; i < recording.length; i++) recording[i] = (Math.random() * 2 - 1) * 0.02;
-
-                const offset = 12345;
-                for (let i = 0; i < chirp.length; i++) recording[offset + i] += chirp[i] * 0.3;
-
-                const peak = EchoDsp.findFirstPeak(EchoDsp.matchedFilterEnvelope(recording, chirp));
-                return Math.abs(peak.index - offset);
-            }
-            """);
-
-        Assert.That(error, Is.LessThan(1.0), "arrival should be located to within a sample");
-    }
-
-    [Test]
-    public async Task A_Tone_Cannot_Be_Located_But_A_Chirp_Can()
-    {
-        var ratios = await Page.EvaluateAsync<double[]>("""
-            () => {
-                const sampleRate = 48000;
-                const sidelobeRatio = template => {
-                    const recording = new Float32Array(sampleRate / 2);
-                    const offset = 8000;
-                    for (let i = 0; i < template.length; i++) recording[offset + i] += template[i];
-
-                    const envelope = EchoDsp.matchedFilterEnvelope(recording, template);
-                    const peak = EchoDsp.maxInRange(envelope, 0, envelope.length);
-                    let highest = 0;
-                    for (let i = 0; i < envelope.length; i++) {
-                        if (Math.abs(i - peak.index) < 200) continue;
-                        highest = Math.max(highest, envelope[i]);
-                    }
-                    return highest / peak.value;
-                };
-
-                const chirp = EchoDsp.makeChirp({ sampleRate, durationSeconds: 0.05, startHz: 2000, endHz: 8000 });
-                const tone = EchoDsp.makeChirp({ sampleRate, durationSeconds: 0.05, startHz: 5000, endHz: 5000 });
-                return [sidelobeRatio(chirp), sidelobeRatio(tone)];
-            }
-            """);
-
-        Assert.That(ratios[1], Is.GreaterThan(0.5), "a tone should correlate almost as well far from the true arrival");
-        Assert.That(ratios[0], Is.LessThan(0.25), "a chirp should give one unambiguous arrival");
-    }
-
-    [Test]
-    public async Task Clock_Offset_And_Pipeline_Latency_Cancel()
-    {
-        var distance = await Page.EvaluateAsync<double>("""
-            () => {
-                const sampleRate = 48000;
-                const speedOfSound = 343;
-                const flight = (4.2 / speedOfSound) * sampleRate;
-                const slot = 0.4 * sampleRate;
-                const offsetB = 987654;
-                const latencyA = 0.031 * sampleRate;
-                const latencyB = 0.128 * sampleRate;
-
-                return EchoDsp.pairDistance({
-                    a1: latencyA,
-                    a2: slot + latencyB + flight,
-                    b1: offsetB + latencyA + flight,
-                    b2: offsetB + slot + latencyB,
-                    sampleRate,
-                    speedOfSound
-                });
-            }
-            """);
-
-        Assert.That(distance, Is.EqualTo(4.2).Within(0.001));
-    }
-
-    [Test]
-    public async Task Collocated_Devices_Read_Zero_Before_Calibration()
-    {
-        var distance = await Page.EvaluateAsync<double>("""
-            () => {
-                const sampleRate = 48000;
-                const speedOfSound = 343;
-                const spacing = (0.19 / speedOfSound) * sampleRate;
-                const slot = 0.4 * sampleRate;
-                const latencyA = 0.04 * sampleRate;
-                const latencyB = 0.11 * sampleRate;
-
-                // Two tabs on one machine: one speaker, one microphone, so the self path and the
-                // cross path are the same physical distance.
-                return EchoDsp.pairDistance({
-                    a1: latencyA + spacing,
-                    a2: slot + latencyB + spacing,
-                    b1: latencyA + spacing,
-                    b2: slot + latencyB + spacing,
-                    sampleRate,
-                    speedOfSound
-                });
-            }
-            """);
-
-        Assert.That(distance, Is.EqualTo(0).Within(0.001));
-    }
-
-    [Test]
-    public async Task Speaker_To_Microphone_Spacing_Is_Added_Back()
-    {
-        var distances = await Page.EvaluateAsync<double[]>("""
-            () => {
-                const sampleRate = 48000;
-                const speedOfSound = 343;
-                const truth = 3.0;
-                const epsilonA = 0.18;
-                const epsilonB = 0.04;
-                const samples = metres => (metres / speedOfSound) * sampleRate;
-                const slot = 0.4 * sampleRate;
-
-                const peaks = {
-                    a1: samples(epsilonA),
-                    a2: slot + samples(truth),
-                    b1: samples(truth),
-                    b2: slot + samples(epsilonB),
-                    sampleRate,
-                    speedOfSound
-                };
-
-                return [
-                    EchoDsp.pairDistance(peaks),
-                    EchoDsp.pairDistance({ ...peaks, epsilonA, epsilonB })
-                ];
-            }
-            """);
-
-        Assert.That(distances[0], Is.EqualTo(3.0 - 0.11).Within(0.005), "uncorrected range reads short");
-        Assert.That(distances[1], Is.EqualTo(3.0).Within(0.005), "correcting for spacing recovers the true range");
-    }
-
-    [Test]
-    public async Task Simulated_Room_Recovers_Distances_And_Layout()
-    {
-        var errors = await Page.EvaluateAsync<double[]>("""
-            () => {
-                const result = EchoSim.runRound({
-                    positions: [[0, 0], [3.2, 0], [3.0, 2.6], [0.4, 2.9], [1.7, 1.4]]
-                });
-                return [EchoSim.worstDistanceError(result), EchoSim.worstPositionError(result), result.keep.length];
-            }
-            """);
-
-        Assert.That(errors[2], Is.EqualTo(5), "every device should survive a clean round");
-        Assert.That(errors[0], Is.LessThan(0.05), "worst pairwise range error");
-        Assert.That(errors[1], Is.LessThan(0.15), "worst recovered position error");
-    }
-
-    [Test]
-    public async Task A_Reflection_Louder_Than_The_Direct_Path_Does_Not_Win()
-    {
-        var errors = await Page.EvaluateAsync<double[]>("""
-            () => {
-                const measure = relativeThreshold => EchoSim.worstDistanceError(EchoSim.runRound({
-                    positions: [[0, 0], [3.4, 0], [2.9, 2.7], [0.2, 2.5]],
-                    reflections: [{ extraMetres: 1.8, gain: 5 }],
-                    peakOptions: { relativeThreshold }
-                }));
-
-                return [measure(undefined), measure(0.5)];
-            }
-            """);
-
-        Assert.That(errors[0], Is.LessThan(0.05), "the first arrival is the distance, not the loudest one");
-        Assert.That(errors[1], Is.GreaterThan(1.5),
-            "a threshold high enough to miss the direct path must measure the reflection instead — this is what the default guards against");
-    }
-
-    [Test]
-    public async Task Echoes_Inside_The_Correlation_Lobe_Bound_The_Accuracy()
-    {
-        var errors = await Page.EvaluateAsync<double[]>("""
-            () => {
-                const positions = [[0, 0], [3.2, 0], [3.0, 2.6], [0.4, 2.9], [1.7, 1.4]];
-                const worst = reflectionExtraRange =>
-                    EchoSim.worstDistanceError(EchoSim.runRound({ positions, reflectionExtraRange }));
-
-                return [worst([0.4, 4.0]), worst([0.08, 0.4])];
-            }
-            """);
-
-        Assert.That(errors[0], Is.LessThan(0.01), "echoes well clear of the direct arrival are rejected outright");
-        Assert.That(errors[1], Is.LessThan(0.15),
-            "echoes arriving inside the correlation lobe cannot be separated and bias the range — this bounds what a device resting on a hard surface can achieve");
-    }
-
-    [Test]
-    public async Task A_Bad_Measurement_Is_Rejected_And_The_Layout_Survives()
-    {
-        var outcome = await Page.EvaluateAsync<double[]>("""
-            () => {
-                const positions = [[0, 0], [3.2, 0], [3.0, 2.6], [0.4, 2.9], [1.6, 1.3]];
-                const config = EchoSim.buildConfiguration({ positions });
-                const reports = EchoSim.detectAll(EchoSim.synthesizeRound(config), config);
-
-                reports[3].peaks[0] += 9000;
-
-                const solved = EchoDsp.solveRound(reports, { speedOfSound: config.speedOfSound });
-                const truth = solved.keep.map(index => positions[index]);
-                const aligned = EchoDsp.alignToReference(solved.points, truth);
-                const worst = Math.max(...aligned.map((point, i) => EchoSim.separation(point, truth[i])));
-                const brokenPairSurvived = solved.keep.includes(0) && solved.keep.includes(3);
-
-                return [solved.keep.length, brokenPairSurvived ? 1 : 0, worst];
-            }
-            """);
-
-        Assert.That(outcome[0], Is.EqualTo(4), "exactly one endpoint of the bad pair should be dropped");
-        Assert.That(outcome[1], Is.EqualTo(0), "the impossible pair must not survive");
-        Assert.That(outcome[2], Is.LessThan(0.2), "the remaining layout should be unpoisoned");
-    }
-
-    [Test]
-    public async Task Alignment_Undoes_An_Arbitrary_Rotation_And_Mirror()
-    {
-        var errors = await Page.EvaluateAsync<double[]>("""
-            () => {
-                const reference = [[0, 0], [3.4, 0], [2.9, 2.7], [0.2, 2.5]];
-                const scramble = (points, angle, mirror) => points.map(([x, y]) => {
-                    const mx = x * mirror;
-                    return [mx * Math.cos(angle) - y * Math.sin(angle) + 11, mx * Math.sin(angle) + y * Math.cos(angle) - 4];
-                });
-
-                const worst = mirror => {
-                    const aligned = EchoDsp.alignToReference(scramble(reference, 0.9, mirror), reference);
-                    return Math.max(...aligned.map((point, i) => EchoSim.separation(point, reference[i])));
-                };
-
-                return [worst(1), worst(-1)];
-            }
-            """);
-
-        Assert.That(errors[0], Is.LessThan(1e-9), "rotation and translation should be recovered exactly");
-        Assert.That(errors[1], Is.LessThan(1e-9), "a mirrored solve should be un-mirrored onto the reference");
-    }
-
-    [Test]
-    public async Task Consecutive_Frames_Do_Not_Rotate_Or_Flip()
-    {
-        var drift = await Page.EvaluateAsync<double>("""
-            () => {
-                const positions = [[0, 0], [3.2, 0], [3.0, 2.6], [0.4, 2.9]];
-                const first = EchoSim.runRound({ positions, seed: 11 });
-
-                const previous = new Array(positions.length).fill(null);
-                first.keep.forEach((device, i) => { previous[device] = first.points[i]; });
-
-                const config = EchoSim.buildConfiguration({ positions, seed: 22 });
-                const reports = EchoSim.detectAll(EchoSim.synthesizeRound(config), config);
-                const second = EchoDsp.solveRound(reports, {
-                    speedOfSound: config.speedOfSound,
-                    previousPoints: previous
-                });
-
-                return Math.max(...second.keep.map((device, i) => EchoSim.separation(second.points[i], previous[device])));
-            }
-            """);
-
-        Assert.That(drift, Is.LessThan(0.3), "a stationary room should not move between frames");
-    }
-}

JoshHeaps.Net.UiTests/EchoRoomTests.cs

@@ -1,244 +0,0 @@
-using Microsoft.Playwright;
-using Microsoft.Playwright.NUnit;
-using NUnit.Framework;
-
-namespace JoshHeaps.Net.UiTests;
-
-/// <summary>
-/// Drives two real browsers through a real room: the hub, the round scheduler, slot rotation,
-/// detection and the solve all run unchanged. Only the microphone is synthetic, so the answer is
-/// known in advance — this is everything except the acoustics.
-/// </summary>
-[TestFixture]
-public class EchoRoomTests : PlaywrightTest
-{
-    private const double TargetMetres = 2.5;
-    private IPlaywright? _playwright;
-    private IBrowser? _browser;
-    private readonly List<IBrowserContext> _contexts = [];
-    private TestConfiguration Config => TestConfiguration.Instance;
-
-    [OneTimeSetUp]
-    public async Task LaunchBrowser()
-    {
-        // Its own Playwright instance and browser: the fake-media launch flags have to be set at
-        // launch time, and the fixture-managed browser is already running by the time tests start.
-        _playwright = await Microsoft.Playwright.Playwright.CreateAsync();
-        _browser = await _playwright.Chromium.LaunchAsync(new BrowserTypeLaunchOptions
-        {
-            Headless = true,
-            Args =
-            [
-                "--use-fake-ui-for-media-stream",
-                "--use-fake-device-for-media-stream",
-                "--autoplay-policy=no-user-gesture-required"
-            ]
-        });
-    }
-
-    [OneTimeTearDown]
-    public async Task CloseBrowser()
-    {
-        if (_browser is not null) await _browser.CloseAsync();
-        _playwright?.Dispose();
-    }
-
-    [TearDown]
-    public async Task CloseContexts()
-    {
-        foreach (var context in _contexts) await context.CloseAsync();
-        _contexts.Clear();
-    }
-
-    [Test]
-    public async Task Two_Devices_Measure_The_Distance_Between_Them()
-    {
-        var roomCode = $"T{Random.Shared.Next(1000, 9999)}";
-        var first = await NewDeviceAsync(roomCode, "laptop");
-        var second = await NewDeviceAsync(roomCode, "phone");
-
-        await Expect(first.Locator("#echoRoster li")).ToHaveCountAsync(2);
-
-        var measured = await WaitForMeasurementAsync(first);
-        var alsoMeasured = await WaitForMeasurementAsync(second);
-
-        Assert.That(measured, Is.EqualTo(TargetMetres).Within(0.05), "the first device's range");
-        Assert.That(alsoMeasured, Is.EqualTo(TargetMetres).Within(0.05), "both devices should agree");
-    }
-
-    [Test]
-    public async Task A_Device_Leaving_Stops_The_Rounds_And_Rejoining_Resumes_Them()
-    {
-        var roomCode = $"T{Random.Shared.Next(1000, 9999)}";
-        var first = await NewDeviceAsync(roomCode, "laptop");
-        var second = await NewDeviceAsync(roomCode, "phone");
-
-        await WaitForMeasurementAsync(first);
-        await second.ClickAsync("#echoLeave");
-
-        await Expect(first.Locator("#echoRoster li")).ToHaveCountAsync(1);
-        await Expect(first.Locator("#echoStatus")).ToContainTextAsync("Waiting for a second device");
-
-        await second.ClickAsync("#echoJoin");
-        await Expect(first.Locator("#echoRoster li")).ToHaveCountAsync(2);
-        Assert.That(await WaitForMeasurementAsync(first), Is.EqualTo(TargetMetres).Within(0.05));
-    }
-
-    /// <summary>
-    /// A stalled main thread is the two-tabs-on-one-machine failure: only one tab is visible, so the
-    /// other gets throttled and its round handling runs late. A late chirp attributed to the wrong
-    /// slot yields a plausible-looking but completely wrong range, so the requirement is not "always
-    /// measures" — it is "never reports a wrong answer". A round it cannot hit must be sat out.
-    /// </summary>
-    [Test]
-    public async Task A_Stalled_Device_Sits_Rounds_Out_Instead_Of_Reporting_Nonsense()
-    {
-        var roomCode = $"T{Random.Shared.Next(1000, 9999)}";
-        var first = await NewDeviceAsync(roomCode, "laptop");
-        var second = await NewDeviceAsync(roomCode, "phone", stallMilliseconds: 900);
-
-        await Expect(first.Locator("#echoRoster li")).ToHaveCountAsync(2);
-        await first.EvaluateAsync("() => { window.__seen = []; }");
-        await first.EvaluateAsync("""
-            () => {
-                const original = EchoPage.renderSolved.bind(EchoPage);
-                EchoPage.renderSolved = update => {
-                    const range = update.solved?.matrix?.[0]?.[1];
-                    if (range != null) window.__seen.push(range);
-                    return original(update);
-                };
-            }
-            """);
-
-        await first.WaitForTimeoutAsync(20000);
-        var seen = await first.EvaluateAsync<double[]>("() => window.__seen");
-        var satOut = await second.EvaluateAsync<int>("() => EchoSession.skippedRounds");
-
-        TestContext.Out.WriteLine($"reported ranges: {string.Join(", ", seen.Select(r => r.ToString("0.000")))}, sat out: {satOut}");
-        Assert.That(satOut, Is.GreaterThan(0),
-            "the stall must actually have cost the device some slots, or this test proves nothing");
-        Assert.That(seen, Is.Not.Empty, "a stalled peer should still let some rounds through");
-        Assert.That(seen, Is.All.EqualTo(TargetMetres).Within(0.05),
-            "every range that gets reported must be right — a stalled device must sit the round out, not chirp late");
-    }
-
-    [Test]
-    public async Task The_Capture_Worklet_Keeps_A_Continuous_Readable_Stream()
-    {
-        var page = await NewDeviceAsync($"T{Random.Shared.Next(1000, 9999)}", "laptop", fakeMicrophone: false);
-
-        await page.WaitForFunctionAsync(
-            "() => EchoAudio.highestFrame > 48000",
-            null,
-            new PageWaitForFunctionOptions { Timeout = 15000, PollingInterval = 100 });
-
-        var capture = await page.EvaluateAsync<double[]>("""
-            () => [
-                EchoAudio.context.sampleRate,
-                EchoAudio.warnings.length,
-                EchoAudio.read(EchoAudio.highestFrame - 24000, 24000)?.length ?? 0,
-                EchoAudio.read(EchoAudio.highestFrame + 1000, 100) === null ? 1 : 0,
-                Math.abs(EchoAudio.frameAt(EchoAudio.context.currentTime) - EchoAudio.highestFrame)
-            ]
-            """);
-
-        Assert.That(capture[0], Is.EqualTo(48000), "the pipeline assumes it got the rate it asked for");
-        Assert.That(capture[1], Is.EqualTo(0), "a clean fake device should raise no capture warnings");
-        Assert.That(capture[2], Is.EqualTo(24000), "recent audio must be readable out of the ring");
-        Assert.That(capture[3], Is.EqualTo(1), "reads past the captured end must fail rather than return silence");
-        Assert.That(capture[4], Is.LessThan(48000),
-            "the frame index and the context clock must stay in the same domain — a scheduled playback time is converted straight into a recording position");
-    }
-
-    /// <summary>
-    /// A page joined to the room with its microphone replaced by a synthesizer. Every slot's chirp
-    /// is placed where a room of this geometry would put it, including a different unknown output
-    /// latency per slot so the cancellation is actually exercised.
-    /// </summary>
-    private async Task<IPage> NewDeviceAsync(
-        string roomCode,
-        string name,
-        bool fakeMicrophone = true,
-        int stallMilliseconds = 0)
-    {
-        var context = await _browser!.NewContextAsync(new BrowserNewContextOptions
-        {
-            IgnoreHTTPSErrors = true,
-            Permissions = ["microphone"]
-        });
-
-        _contexts.Add(context);
-        var page = await context.NewPageAsync();
-        page.Console += (_, message) =>
-        {
-            if (message.Type == "error") TestContext.Out.WriteLine($"[{name} console] {message.Text}");
-        };
-
-        await page.GotoAsync($"{Config.Test.BaseUrl}/echo?room={roomCode}");
-        await page.FillAsync("#echoName", name);
-        if (fakeMicrophone) await page.EvaluateAsync(FakeMicrophoneScript, TargetMetres);
-        if (stallMilliseconds > 0) await page.EvaluateAsync(StallScript, stallMilliseconds);
-        await page.ClickAsync("#echoJoin");
-
-        return page;
-    }
-
-    /// <summary>Blocks the main thread on every round announcement, the way a throttled tab does.</summary>
-    private const string StallScript = """
-        stallMs => {
-            const original = EchoSession.handleRoundStarting.bind(EchoSession);
-            EchoSession.handleRoundStarting = schedule => {
-                const until = performance.now() + stallMs;
-                while (performance.now() < until) { /* hold the thread */ }
-                return original(schedule);
-            };
-        }
-        """;
-
-    private static async Task<double> WaitForMeasurementAsync(IPage page)
-    {
-        await page.WaitForFunctionAsync(
-            "() => EchoPage.lastSolved?.solved?.matrix?.[0]?.[1] != null",
-            null,
-            new PageWaitForFunctionOptions { Timeout = 30000, PollingInterval = 250 });
-
-        return await page.EvaluateAsync<double>("() => EchoPage.lastSolved.solved.matrix[0][1]");
-    }
-
-    /// <summary>
-    /// Synthesizes what the microphone would have heard for this round. The device's own chirp is
-    /// placed at the frame it was actually scheduled for rather than at its nominal slot position,
-    /// so any drift between "when the round said to play" and "when playback was really booked"
-    /// reaches the detector instead of being papered over by the harness.
-    /// </summary>
-    private const string FakeMicrophoneScript = """
-        targetMetres => {
-            const speedOfSound = 343;
-            const epsilonMetres = 0.08;
-            const latencyBySlot = [1400, 5200, 2600, 7100, 900, 4300, 3300, 6000];
-
-            EchoAudio.read = (startFrame, length) => {
-                const round = EchoSession.pending ?? EchoSession.lastRound;
-                if (!round) return null;
-
-                const chirp = EchoSession.chirp;
-                const toSamples = metres => Math.round((metres / speedOfSound) * round.sampleRate);
-                const recording = new Float32Array(length);
-
-                round.schedule.slotOrder.forEach((_, slot) => {
-                    const own = slot === round.ownSlot;
-                    const origin = own
-                        ? round.scheduledFrame - round.windowStart
-                        : round.leadInSamples + slot * round.slotSamples;
-                    const at = origin + latencyBySlot[slot] + toSamples(own ? epsilonMetres : targetMetres);
-                    const amplitude = own ? 1.0 : 0.25;
-
-                    for (let i = 0; i < chirp.length && at + i < length; i++) recording[at + i] += chirp[i] * amplitude;
-                });
-
-                for (let i = 0; i < length; i++) recording[i] += (Math.random() * 2 - 1) * 0.01;
-                return recording;
-            };
-        }
-        """;
-}

JoshHeaps.Net/Hubs/EchoHub.cs

@@ -1,52 +0,0 @@
-using JoshHeaps.Net.Models;
-using JoshHeaps.Net.Services.Interfaces;
-using Microsoft.AspNetCore.SignalR;
-
-namespace JoshHeaps.Net.Hubs;
-
-/// <summary>
-/// Membership and peak reporting for acoustic ranging rooms. Nothing that arrives here is audio:
-/// a report is a handful of sample indices, and the geometry is solved on the clients.
-/// </summary>
-public class EchoHub(IEchoRoomStore rooms) : Hub
-{
-    /// <summary>Join (or create) a room and receive an id plus the current roster.</summary>
-    public async Task<EchoJoinResult> JoinRoom(string roomCode, string displayName, int sampleRate)
-    {
-        var result = rooms.Join(roomCode, Context.ConnectionId, displayName, sampleRate);
-        await Groups.AddToGroupAsync(Context.ConnectionId, GroupFor(result.RoomCode));
-        await Clients.Group(GroupFor(result.RoomCode)).SendAsync("RoomChanged", result.Room);
-
-        return result;
-    }
-
-    /// <summary>File this device's arrival indices for the room's open round.</summary>
-    public bool ReportRound(EchoPeakReport report) => rooms.Report(Context.ConnectionId, report);
-
-    /// <summary>
-    /// Server clock, for estimating each device's offset from it. Only needs to be good to a few
-    /// tens of milliseconds: it decides which chirp is whose, never how far away anything is.
-    /// </summary>
-    public long ServerTime() => DateTimeOffset.UtcNow.ToUnixTimeMilliseconds();
-
-    public async Task<bool> LeaveRoom() => await RemoveFromRoom();
-
-    public override async Task OnDisconnectedAsync(Exception? exception)
-    {
-        await RemoveFromRoom();
-        await base.OnDisconnectedAsync(exception);
-    }
-
-    internal static string GroupFor(string roomCode) => $"echo:{roomCode.ToUpperInvariant()}";
-
-    private async Task<bool> RemoveFromRoom()
-    {
-        var (roomCode, room) = rooms.Leave(Context.ConnectionId);
-        if (roomCode is null) return false;
-
-        await Groups.RemoveFromGroupAsync(Context.ConnectionId, GroupFor(roomCode));
-        if (room is not null) await Clients.Group(GroupFor(roomCode)).SendAsync("RoomChanged", room);
-
-        return true;
-    }
-}

JoshHeaps.Net/Models/EchoModels.cs

@@ -1,84 +0,0 @@
-namespace JoshHeaps.Net.Models;
-
-/// <summary>A device taking part in a ranging room.</summary>
-public sealed class EchoDevice
-{
-    public required string DeviceId { get; init; }
-    public required string ConnectionId { get; init; }
-    public required string DisplayName { get; set; }
-    public int SampleRate { get; set; }
-}
-
-/// <summary>
-/// One chirp cycle: every device plays in turn, and every device listens to the whole thing.
-/// </summary>
-public sealed class EchoRound
-{
-    public required string RoundId { get; init; }
-    public required string[] SlotOrder { get; init; }
-    public int SlotMilliseconds { get; init; }
-    public DateTimeOffset Deadline { get; init; }
-    public Dictionary<string, EchoPeakReport> Reports { get; } = [];
-}
-
-/// <summary>
-/// What one device heard. Peaks are fractional sample indices into that device's own continuous
-/// recording, one per slot, null where a chirp was not detected. Nothing else is ever uploaded.
-/// </summary>
-public sealed class EchoPeakReport
-{
-    public required string DeviceId { get; init; }
-    public required string RoundId { get; init; }
-    public int Slot { get; init; }
-    public int SampleRate { get; init; }
-    public double Epsilon { get; init; }
-    public double?[] Peaks { get; init; } = [];
-}
-
-public sealed class EchoJoinResult
-{
-    public required string DeviceId { get; init; }
-    public required string RoomCode { get; init; }
-    public required EchoRoomSnapshot Room { get; init; }
-}
-
-public sealed class EchoRoomSnapshot
-{
-    public required string RoomCode { get; init; }
-    public required EchoDeviceSnapshot[] Devices { get; init; }
-}
-
-public sealed class EchoDeviceSnapshot
-{
-    public required string DeviceId { get; init; }
-    public required string DisplayName { get; init; }
-    public int SampleRate { get; init; }
-}
-
-/// <summary>Tells every device when to chirp: its own slot index and how long a slot lasts.</summary>
-public sealed class EchoRoundSchedule
-{
-    public required string RoundId { get; init; }
-    public required string[] SlotOrder { get; init; }
-    public int SlotMilliseconds { get; init; }
-    public int TailMilliseconds { get; init; }
-
-    /// <summary>
-    /// When slot zero should sound, in server time, set far enough ahead that every device can
-    /// receive the message and book the playback before it arrives. Devices schedule against this
-    /// rather than against message arrival, so one slow client cannot drag its chirp into another
-    /// device's slot and invalidate the round for everybody.
-    /// </summary>
-    public long StartsAtUnixMs { get; init; }
-}
-
-/// <summary>
-/// Every device's peaks for one round, broadcast unchanged. Each client solves the geometry itself
-/// so the server never needs the ranging maths.
-/// </summary>
-public sealed class EchoRoundResult
-{
-    public required string RoundId { get; init; }
-    public required string[] SlotOrder { get; init; }
-    public required EchoPeakReport[] Reports { get; init; }
-}

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

@@ -2,7 +2,7 @@ using Microsoft.AspNetCore.Mvc.RazorPages;
 
 namespace JoshHeaps.Net.Pages
 {
-    public class EchoModel : PageModel
+    public class CasinoModel : PageModel
     {
         public void OnGet()
         {

JoshHeaps.Net/Pages/Casino/TexasHoldem.cshtml

@@ -0,0 +1,249 @@
+@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">Texas Hold'em</div>
+                    <div id="potBadge">
+                        <span id="potBadgeLabel">Pot</span>
+                        <span id="potBadgeAmount">$0</span>
+                    </div>
+                </div>
+                <div id="seatsLayer"></div>
+            </div>
+            <p id="tableHint" class="tableHint"></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>
+                    <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">Every player who didn't go all-in short is assumed to have put in this amount. Enter a smaller amount on a seat only if that player is all-in for less.</p>
+                </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 dollar value, then count chips per seat instead of typing a total.</p>
+                </div>
+            </details>
+
+            <details class="sidebarPanel">
+                <summary>Table Notes</summary>
+                <div class="panelBody">
+                    <textarea id="tableNotes" rows="4" placeholder="Anything else worth tracking — side bets, IOUs, running totals..."></textarea>
+                </div>
+            </details>
+
+            <details class="sidebarPanel">
+                <summary>Session Standings</summary>
+                <div class="panelBody">
+                    <div id="standingsTable">
+                        <div class="standingsRow standingsHeader">
+                            <span>Player</span>
+                            <span>In</span>
+                            <span>Won</span>
+                            <span>Net</span>
+                        </div>
+                        <div id="standingsList"></div>
+                    </div>
+                    <p id="standingsEmptyHint" class="fieldHint">Once you resolve a pot, everyone's running total for the night shows up here.</p>
+                </div>
+            </details>
+
+            <details class="sidebarPanel">
+                <summary>Hand History</summary>
+                <div class="panelBody">
+                    <div id="handHistoryList"></div>
+                    <p id="handHistoryEmptyHint" class="fieldHint">Resolved pots show up here as you play, 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>
+        </aside>
+    </div>
+</div>
+
+<template id="seatTemplate">
+    <div class="seat" draggable="true">
+        <div class="seatChairNumber"></div>
+        <button class="dealerChip" 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>
+</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">
+            <input type="text" class="cardInput card1Input" maxlength="2" placeholder="__" />
+            <input type="text" class="cardInput card2Input" maxlength="2" placeholder="__" />
+        </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" />
+        <input type="number" class="chipValueInput" min="0" step="0.01" placeholder="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>
+    </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="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" 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">
+        <div class="potWizardHeader">
+            <h2>Resolve the Pot</h2>
+            <button id="closePotWizardBtn" 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/render.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/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 +1,60 @@
+@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="splitResult" aria-live="polite">
+        <div id="splitResultLabel">Each player gets</div>
+        <div id="splitResultAmount">$0.00</div>
+        <div id="splitOddNote" hidden></div>
+        <div id="splitDustNote" hidden></div>
+    </div>
+
+    <section class="splitField">
+        <label for="potInput" class="splitLabel">Pot</label>
+        <div class="potInputWrap">
+            <span class="potCurrency">$</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">
+        <span class="splitLabel" id="waysLabel">Split between</span>
+        <div id="waysChoices" class="chipRow" role="group" aria-labelledby="waysLabel"></div>
+    </section>
+
+    <section class="splitField">
+        <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">
+        Uneven pots — someone all-in for less — need the side-pot walkthrough on the
+        <a href="/casino/texasholdem">full table</a>.
+    </p>
+</div>
+
+@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/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/Echo.cshtml

@@ -1,70 +0,0 @@
-@page
-@model JoshHeaps.Net.Pages.EchoModel
-@{
-    Layout = "_Layout";
-    ViewData["Title"] = "Echo";
-}
-
-<div id="echoHeader">
-    <h1>Echo</h1>
-    <p class="echo-blurb">
-        Two devices measure the distance between them by chirping at each other and timing the answer.
-        Each one records continuously and only ever compares arrivals inside its own recording, so no
-        clock synchronisation is needed and the unknown audio latency cancels out.
-    </p>
-    <p class="echo-privacy">Only sample numbers leave your device. The recording never does.</p>
-</div>
-
-<div id="echoControls">
-    <label>Room <input id="echoRoom" type="text" maxlength="6" autocomplete="off" spellcheck="false" /></label>
-    <label>Name <input id="echoName" type="text" maxlength="16" placeholder="this device" autocomplete="off" /></label>
-    <label>
-        Speaker to mic (m)
-        <input id="echoEpsilon" type="number" min="0" max="0.5" step="0.01" />
-    </label>
-    <button id="echoJoin">Join and listen</button>
-    <button id="echoLeave" hidden>Leave</button>
-</div>
-
-<p id="echoStatus" class="echo-status">Pick a room, then open the same room on a second device.</p>
-<p class="echo-share">Join link: <a id="echoShareLink" href="#"></a></p>
-<div id="echoWarnings"></div>
-
-<div id="echoReadout" class="echo-readout"><span class="echo-readout-idle">not measuring</span></div>
-
-<div id="echoPanels">
-    <section class="echo-panel">
-        <h2>Devices</h2>
-        <ul id="echoRoster"></ul>
-    </section>
-    <section class="echo-panel">
-        <h2>Ranges</h2>
-        <div id="echoPairs"></div>
-    </section>
-    <section class="echo-panel">
-        <h2>Timing</h2>
-        <p class="echo-hint">How far each chirp landed from its slot. Steady means the arrivals are being matched to the right devices.</p>
-        <div id="echoDiagnostics"></div>
-    </section>
-</div>
-
-<section class="echo-panel echo-panel-wide">
-    <h2>Matched filter</h2>
-    <p class="echo-hint">Each spike is a chirp arriving. The bright one is this device hearing itself.</p>
-    <canvas id="echoTrace"></canvas>
-</section>
-
-<a class="echo-back" href="/">&larr; Back</a>
-
-@section Scripts {
-    <script src="~/js/signalr/signalr.min.js"></script>
-    <script src="~/js/EchoScripts/EchoDsp.js"></script>
-    <script src="~/js/EchoScripts/EchoAudio.js"></script>
-    <script src="~/js/EchoScripts/EchoSession.js"></script>
-    <script src="~/js/EchoScripts/echoMain.js"></script>
-}
-
-@section Styles {
-    <link rel="stylesheet" href="~/css/variables.css?v=@ViewData["cssVersion"]" />
-    <link rel="stylesheet" href="~/css/echo/echo.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/_Layout.cshtml

@@ -1,6 +1,6 @@
 @{
     Layout = null;
-    ViewData["cssVersion"] = "1.0.7"; // <--- change this once to bust cache
+    ViewData["cssVersion"] = "1.0.8"; // <--- change this once to bust cache
 }
 
 <!DOCTYPE html>

JoshHeaps.Net/Program.cs

@@ -1,7 +1,6 @@
 using JoshHeaps.Net.Hubs;
 using JoshHeaps.Net.Services.Implementations;
 using JoshHeaps.Net.Services.Interfaces;
-using Microsoft.Extensions.Options;
 
 var builder = WebApplication.CreateBuilder(args);
 
@@ -31,12 +30,6 @@ builder.Services.AddSingleton<IGameStore, GameStore>();
 builder.Services.AddSingleton<ISelfPlayCoordinator, SelfPlayCoordinator>();
 builder.Services.AddSingleton<AutoTrainingSettings>();
 
-builder.Services.Configure<EchoRoundSettings>(configuration.GetSection(EchoRoundSettings.SectionName));
-builder.Services.AddSingleton(provider =>
-    provider.GetRequiredService<IOptions<EchoRoundSettings>>().Value);
-builder.Services.AddSingleton<IEchoRoomStore, EchoRoomStore>();
-builder.Services.AddHostedService<EchoRoundService>();
-
 if (!builder.Environment.IsDevelopment())
 {
     builder.Services.AddHostedService<AutoIpUpdateService>();
@@ -79,6 +72,4 @@ app.MapControllers();
 
 app.MapHub<ChessHub>("/chessHub");
 
-app.MapHub<EchoHub>("/echoHub");
-
 app.Run();

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/EchoRoomStore.cs

@@ -1,189 +0,0 @@
-using System.Collections.Concurrent;
-using JoshHeaps.Net.Models;
-using JoshHeaps.Net.Services.Interfaces;
-
-namespace JoshHeaps.Net.Services.Implementations;
-
-/// <summary>
-/// In-memory ranging rooms. Singleton: rooms are process-wide and short-lived, and the site runs
-/// as a single instance, so there is nothing to persist and no backplane to coordinate.
-/// </summary>
-public sealed class EchoRoomStore : IEchoRoomStore
-{
-    private sealed class Room
-    {
-        public required string Code { get; init; }
-        public List<EchoDevice> Devices { get; } = [];
-        public EchoRound? Round { get; set; }
-        public int RoundCounter { get; set; }
-        public DateTimeOffset LastActivity { get; set; } = DateTimeOffset.UtcNow;
-    }
-
-    private readonly ConcurrentDictionary<string, Room> _rooms = new(StringComparer.OrdinalIgnoreCase);
-    private readonly ConcurrentDictionary<string, string> _roomsByConnection = [];
-
-    public EchoJoinResult Join(string roomCode, string connectionId, string displayName, int sampleRate)
-    {
-        var room = _rooms.GetOrAdd(roomCode, code => new Room { Code = code });
-        var device = new EchoDevice
-        {
-            DeviceId = Guid.NewGuid().ToString("N")[..8],
-            ConnectionId = connectionId,
-            DisplayName = displayName,
-            SampleRate = sampleRate
-        };
-
-        lock (room)
-        {
-            room.Devices.RemoveAll(existing => existing.ConnectionId == connectionId);
-            room.Devices.Add(device);
-            room.LastActivity = DateTimeOffset.UtcNow;
-            _roomsByConnection[connectionId] = room.Code;
-
-            return new EchoJoinResult { DeviceId = device.DeviceId, RoomCode = room.Code, Room = SnapshotLocked(room) };
-        }
-    }
-
-    public (string? roomCode, EchoRoomSnapshot? room) Leave(string connectionId)
-    {
-        if (!_roomsByConnection.TryRemove(connectionId, out var roomCode)) return (null, null);
-        if (!_rooms.TryGetValue(roomCode, out var room)) return (roomCode, null);
-
-        lock (room)
-        {
-            room.Devices.RemoveAll(device => device.ConnectionId == connectionId);
-            room.Round = null;
-            room.LastActivity = DateTimeOffset.UtcNow;
-
-            if (room.Devices.Count == 0) _rooms.TryRemove(roomCode, out _);
-
-            return (roomCode, SnapshotLocked(room));
-        }
-    }
-
-    public EchoRoomSnapshot? Snapshot(string roomCode)
-    {
-        if (!_rooms.TryGetValue(roomCode, out var room)) return null;
-
-        lock (room) return SnapshotLocked(room);
-    }
-
-    public IReadOnlyCollection<string> MeasurableRooms =>
-        [.. _rooms.Values.Where(room => room.Devices.Count >= 2).Select(room => room.Code)];
-
-    public EchoRoundSchedule? StartRound(
-        string roomCode,
-        int slotMilliseconds,
-        int tailMilliseconds,
-        TimeSpan lead,
-        TimeSpan grace)
-    {
-        if (!_rooms.TryGetValue(roomCode, out var room)) return null;
-
-        lock (room)
-        {
-            if (room.Round is not null || room.Devices.Count < 2) return null;
-
-            var slotOrder = RotatedSlotOrder(room);
-            var startsAt = DateTimeOffset.UtcNow + lead;
-            var duration = TimeSpan.FromMilliseconds(slotOrder.Length * slotMilliseconds + tailMilliseconds);
-
-            room.Round = new EchoRound
-            {
-                RoundId = Guid.NewGuid().ToString("N")[..12],
-                SlotOrder = slotOrder,
-                SlotMilliseconds = slotMilliseconds,
-                Deadline = startsAt + duration + grace
-            };
-            room.LastActivity = DateTimeOffset.UtcNow;
-
-            return new EchoRoundSchedule
-            {
-                RoundId = room.Round.RoundId,
-                SlotOrder = slotOrder,
-                SlotMilliseconds = slotMilliseconds,
-                TailMilliseconds = tailMilliseconds,
-                StartsAtUnixMs = startsAt.ToUnixTimeMilliseconds()
-            };
-        }
-    }
-
-    public bool Report(string connectionId, EchoPeakReport report)
-    {
-        var device = FindDevice(connectionId, out var room);
-        if (device is null || room is null) return false;
-
-        lock (room)
-        {
-            if (room.Round?.RoundId != report.RoundId) return false;
-            if (!room.Round.SlotOrder.Contains(device.DeviceId)) return false;
-
-            room.Round.Reports[device.DeviceId] = report;
-            room.LastActivity = DateTimeOffset.UtcNow;
-            return true;
-        }
-    }
-
-    public EchoRoundResult? TryCloseRound(string roomCode)
-    {
-        if (!_rooms.TryGetValue(roomCode, out var room)) return null;
-
-        lock (room)
-        {
-            var round = room.Round;
-            if (round is null) return null;
-
-            var everyoneReported = round.SlotOrder.All(round.Reports.ContainsKey);
-            if (!everyoneReported && DateTimeOffset.UtcNow < round.Deadline) return null;
-
-            room.Round = null;
-
-            return new EchoRoundResult
-            {
-                RoundId = round.RoundId,
-                SlotOrder = round.SlotOrder,
-                Reports = [.. round.SlotOrder.Where(round.Reports.ContainsKey).Select(id => round.Reports[id])]
-            };
-        }
-    }
-
-    public int PruneIdle(TimeSpan idleFor)
-    {
-        var cutoff = DateTimeOffset.UtcNow - idleFor;
-        var stale = _rooms.Values.Where(room => room.LastActivity < cutoff).Select(room => room.Code).ToList();
-
-        foreach (var code in stale) _rooms.TryRemove(code, out _);
-
-        return stale.Count;
-    }
-
-    private static EchoRoomSnapshot SnapshotLocked(Room room) =>
-        new()
-        {
-            RoomCode = room.Code,
-            Devices =
-            [
-                .. room.Devices.Select(device => new EchoDeviceSnapshot
-                {
-                    DeviceId = device.DeviceId,
-                    DisplayName = device.DisplayName,
-                    SampleRate = device.SampleRate
-                })
-            ]
-        };
-
-    private static string[] RotatedSlotOrder(Room room)
-    {
-        var offset = room.RoundCounter++ % room.Devices.Count;
-        return [.. room.Devices.Skip(offset).Concat(room.Devices.Take(offset)).Select(device => device.DeviceId)];
-    }
-
-    private EchoDevice? FindDevice(string connectionId, out Room? room)
-    {
-        room = null;
-        if (!_roomsByConnection.TryGetValue(connectionId, out var roomCode)) return null;
-        if (!_rooms.TryGetValue(roomCode, out room)) return null;
-
-        lock (room) return room.Devices.FirstOrDefault(device => device.ConnectionId == connectionId);
-    }
-}

JoshHeaps.Net/Services/Implementations/EchoRoundService.cs

@@ -1,107 +0,0 @@
-using JoshHeaps.Net.Hubs;
-using JoshHeaps.Net.Services.Interfaces;
-using Microsoft.AspNetCore.SignalR;
-
-namespace JoshHeaps.Net.Services.Implementations;
-
-public sealed class EchoRoundSettings
-{
-    public const string SectionName = "Echo";
-
-    /// <summary>
-    /// Slot length. Wide enough that no device's chirp can land in another's search window once
-    /// unknown output latency (tens of milliseconds, different per device) and message jitter are
-    /// accounted for.
-    /// </summary>
-    public int SlotMilliseconds { get; set; } = 500;
-
-    /// <summary>Time after the last chirp for propagation, detection and reporting.</summary>
-    public int TailMilliseconds { get; set; } = 700;
-
-    public int GraceMilliseconds { get; set; } = 1500;
-    public int GapMilliseconds { get; set; } = 250;
-    public int IdleRoomMinutes { get; set; } = 10;
-
-    /// <summary>
-    /// How far ahead a round is announced. Must exceed the worst message delivery plus client
-    /// stall, or a device will find its slot already gone and sit the round out.
-    /// </summary>
-    public int LeadMilliseconds { get; set; } = 600;
-}
-
-/// <summary>
-/// Drives continuous ranging: opens a round for every room that has two or more devices, closes it
-/// once everyone has reported or the deadline passes, and broadcasts the raw peak table.
-/// </summary>
-public sealed class EchoRoundService(
-    IEchoRoomStore rooms,
-    IHubContext<EchoHub> hub,
-    EchoRoundSettings settings,
-    ILogger<EchoRoundService> logger) : BackgroundService
-{
-    private readonly Dictionary<string, DateTimeOffset> _nextRoundAllowedAt = [];
-
-    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
-    {
-        var lastPrune = DateTimeOffset.UtcNow;
-
-        while (!stoppingToken.IsCancellationRequested)
-        {
-            try
-            {
-                await TickAsync();
-                lastPrune = PruneIfDue(lastPrune);
-            }
-            catch (Exception error)
-            {
-                logger.LogError(error, "Echo round tick failed");
-            }
-
-            await Task.Delay(50, stoppingToken);
-        }
-    }
-
-    private async Task TickAsync()
-    {
-        foreach (var roomCode in rooms.MeasurableRooms)
-        {
-            await CloseFinishedRoundAsync(roomCode);
-            await OpenRoundIfDueAsync(roomCode);
-        }
-    }
-
-    private async Task CloseFinishedRoundAsync(string roomCode)
-    {
-        var result = rooms.TryCloseRound(roomCode);
-        if (result is null) return;
-
-        _nextRoundAllowedAt[roomCode] = DateTimeOffset.UtcNow.AddMilliseconds(settings.GapMilliseconds);
-        await hub.Clients.Group(EchoHub.GroupFor(roomCode)).SendAsync("RoundComplete", result);
-    }
-
-    private async Task OpenRoundIfDueAsync(string roomCode)
-    {
-        if (_nextRoundAllowedAt.TryGetValue(roomCode, out var earliest) && DateTimeOffset.UtcNow < earliest) return;
-
-        var schedule = rooms.StartRound(
-            roomCode,
-            settings.SlotMilliseconds,
-            settings.TailMilliseconds,
-            TimeSpan.FromMilliseconds(settings.LeadMilliseconds),
-            TimeSpan.FromMilliseconds(settings.GraceMilliseconds));
-
-        if (schedule is null) return;
-
-        await hub.Clients.Group(EchoHub.GroupFor(roomCode)).SendAsync("RoundStarting", schedule);
-    }
-
-    private DateTimeOffset PruneIfDue(DateTimeOffset lastPrune)
-    {
-        if (DateTimeOffset.UtcNow - lastPrune < TimeSpan.FromMinutes(1)) return lastPrune;
-
-        var pruned = rooms.PruneIdle(TimeSpan.FromMinutes(settings.IdleRoomMinutes));
-        if (pruned > 0) logger.LogInformation("Pruned {Count} idle echo room(s)", pruned);
-
-        return DateTimeOffset.UtcNow;
-    }
-}

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/IEchoRoomStore.cs

@@ -1,45 +0,0 @@
-using JoshHeaps.Net.Models;
-
-namespace JoshHeaps.Net.Services.Interfaces;
-
-/// <summary>
-/// Process-wide registry of ranging rooms. Holds only device identity and the sample indices each
-/// device reported, so the server is a scheduler and a relay — it never sees audio.
-/// </summary>
-public interface IEchoRoomStore
-{
-    /// <summary>Add a device to a room, creating the room if this is the first arrival.</summary>
-    EchoJoinResult Join(string roomCode, string connectionId, string displayName, int sampleRate);
-
-    /// <summary>Remove whichever device owns this connection, returning the room it left.</summary>
-    (string? roomCode, EchoRoomSnapshot? room) Leave(string connectionId);
-
-    /// <summary>Snapshot of a room's roster, or null if the room is gone.</summary>
-    EchoRoomSnapshot? Snapshot(string roomCode);
-
-    /// <summary>Room codes with at least two devices, which is the minimum for a measurement.</summary>
-    IReadOnlyCollection<string> MeasurableRooms { get; }
-
-    /// <summary>
-    /// Open a new round for a room, rotating which device chirps first so no single device is
-    /// permanently the slot-order anchor.
-    /// </summary>
-    EchoRoundSchedule? StartRound(
-        string roomCode,
-        int slotMilliseconds,
-        int tailMilliseconds,
-        TimeSpan lead,
-        TimeSpan grace);
-
-    /// <summary>File a device's peaks against the room's open round.</summary>
-    bool Report(string connectionId, EchoPeakReport report);
-
-    /// <summary>
-    /// Close the open round if every device has reported or its deadline has passed, returning the
-    /// reports to broadcast.
-    /// </summary>
-    EchoRoundResult? TryCloseRound(string roomCode);
-
-    /// <summary>Drop rooms that have had no activity for longer than <paramref name="idleFor"/>.</summary>
-    int PruneIdle(TimeSpan idleFor);
-}

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 +1,301 @@
+/* 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;
+}
+
+#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;
+}
+
+/* ---------- 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;
+}
+
+.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;
+}
+
+.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;
+}
+
+.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;
+}
+
+.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;
+}
+
+.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;
+}
+
+.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/echo/echo.css

@@ -1,287 +0,0 @@
-body {
-    background: var(--color-bg);
-    color: var(--color-text);
-    font-family: var(--font-body);
-    margin: 0;
-    padding: 2rem 1.25rem 4rem;
-}
-
-#echoHeader {
-    max-width: 46rem;
-    margin: 0 auto 1.5rem;
-}
-
-#echoHeader h1 {
-    color: var(--color-heading);
-    font-size: 2.4rem;
-    letter-spacing: -0.02em;
-    margin: 0 0 0.6rem;
-}
-
-.echo-blurb {
-    line-height: 1.6;
-    margin: 0 0 0.5rem;
-}
-
-.echo-privacy {
-    color: var(--color-text-subtle);
-    font-family: var(--font-mono);
-    font-size: 0.8rem;
-    margin: 0;
-}
-
-#echoControls {
-    align-items: flex-end;
-    display: flex;
-    flex-wrap: wrap;
-    gap: 0.75rem;
-    margin: 0 auto 1rem;
-    max-width: 46rem;
-}
-
-#echoControls label {
-    color: var(--color-text-muted);
-    display: flex;
-    flex-direction: column;
-    font-family: var(--font-mono);
-    font-size: 0.75rem;
-    gap: 0.3rem;
-    text-transform: lowercase;
-}
-
-#echoControls input {
-    background: var(--color-surface-raised);
-    border: 1px solid var(--color-border);
-    border-radius: 6px;
-    color: var(--color-heading);
-    font-family: var(--font-mono);
-    font-size: 1rem;
-    padding: 0.5rem 0.6rem;
-    width: 7rem;
-}
-
-#echoControls input:focus {
-    border-color: var(--color-accent-border);
-    outline: none;
-}
-
-#echoControls button {
-    background: transparent;
-    border: 1px solid var(--color-accent-border);
-    border-radius: 6px;
-    color: var(--color-accent);
-    cursor: pointer;
-    font-family: var(--font-mono);
-    font-size: 0.9rem;
-    padding: 0.6rem 1.1rem;
-    transition: background 0.15s ease, color 0.15s ease;
-}
-
-#echoControls button:hover:not(:disabled) {
-    background: var(--color-accent);
-    color: var(--color-bg);
-}
-
-#echoControls button:disabled {
-    border-color: var(--color-border);
-    color: var(--color-text-subtle);
-    cursor: default;
-}
-
-.echo-status,
-.echo-share {
-    font-family: var(--font-mono);
-    font-size: 0.8rem;
-    margin: 0 auto 0.4rem;
-    max-width: 46rem;
-}
-
-.echo-share a {
-    color: var(--color-accent);
-    text-decoration: none;
-    word-break: break-all;
-}
-
-#echoWarnings {
-    margin: 0 auto;
-    max-width: 46rem;
-}
-
-.echo-warning {
-    background: rgba(255, 170, 0, 0.08);
-    border: 1px solid rgba(255, 170, 0, 0.35);
-    border-radius: 6px;
-    color: #ffcc66;
-    font-size: 0.85rem;
-    line-height: 1.5;
-    margin: 0.5rem 0;
-    padding: 0.7rem 0.9rem;
-}
-
-.echo-readout {
-    align-items: baseline;
-    display: flex;
-    flex-direction: column;
-    gap: 0.4rem;
-    margin: 2rem auto;
-    max-width: 46rem;
-    min-height: 6rem;
-}
-
-.echo-metres {
-    color: var(--color-accent);
-    font-family: var(--font-mono);
-    font-size: clamp(3.5rem, 14vw, 7rem);
-    font-variant-numeric: tabular-nums;
-    line-height: 1;
-}
-
-.echo-metres small {
-    color: var(--color-text-subtle);
-    font-size: 0.28em;
-    margin-left: 0.2em;
-}
-
-.echo-readout-detail,
-.echo-readout-idle {
-    color: var(--color-text-subtle);
-    font-family: var(--font-mono);
-    font-size: 0.8rem;
-}
-
-#echoPanels {
-    display: grid;
-    gap: 1rem;
-    grid-template-columns: repeat(auto-fit, minmax(min(100%, 18rem), 1fr));
-    margin: 0 auto;
-    max-width: 46rem;
-}
-
-.echo-panel {
-    background: var(--color-surface);
-    border: 1px solid var(--color-border);
-    border-radius: 8px;
-    padding: 1rem 1.1rem;
-}
-
-.echo-panel-wide {
-    margin: 1rem auto 0;
-    max-width: 46rem;
-}
-
-.echo-panel h2 {
-    color: var(--color-heading-secondary);
-    font-family: var(--font-mono);
-    font-size: 0.8rem;
-    font-weight: 500;
-    letter-spacing: 0.08em;
-    margin: 0 0 0.75rem;
-    text-transform: uppercase;
-}
-
-.echo-hint {
-    color: var(--color-text-subtle);
-    font-size: 0.8rem;
-    margin: -0.4rem 0 0.75rem;
-}
-
-#echoRoster {
-    list-style: none;
-    margin: 0;
-    padding: 0;
-}
-
-.echo-device {
-    border-bottom: 1px solid var(--color-border);
-    font-family: var(--font-mono);
-    font-size: 0.85rem;
-    padding: 0.45rem 0;
-}
-
-.echo-device:last-child {
-    border-bottom: none;
-}
-
-.echo-device-self {
-    color: var(--color-accent);
-}
-
-#echoPairs {
-    overflow-x: auto;
-}
-
-#echoPairs table {
-    border-collapse: collapse;
-    font-family: var(--font-mono);
-    font-size: 0.85rem;
-    width: 100%;
-}
-
-#echoPairs th {
-    color: var(--color-text-subtle);
-    font-weight: 500;
-    padding: 0 0.6rem 0.4rem 0;
-    text-align: left;
-}
-
-#echoPairs td {
-    border-top: 1px solid var(--color-border);
-    color: var(--color-heading-secondary);
-    font-variant-numeric: tabular-nums;
-    padding: 0.4rem 0.6rem 0.4rem 0;
-}
-
-.echo-dropped td {
-    color: var(--color-text-subtle);
-    text-decoration: line-through;
-}
-
-.echo-slots {
-    list-style: none;
-    margin: 0 0 0.6rem;
-    padding: 0;
-}
-
-.echo-slots li {
-    color: var(--color-heading-secondary);
-    font-family: var(--font-mono);
-    font-size: 0.85rem;
-    font-variant-numeric: tabular-nums;
-    padding: 0.2rem 0;
-}
-
-.echo-slots .echo-missed {
-    color: #ff7676;
-}
-
-.echo-diag-line {
-    color: var(--color-text-subtle);
-    font-family: var(--font-mono);
-    font-size: 0.75rem;
-    line-height: 1.5;
-    margin: 0;
-}
-
-.echo-diag-line strong {
-    color: #ff7676;
-}
-
-#echoTrace {
-    display: block;
-    height: 160px;
-    width: 100%;
-}
-
-.echo-back {
-    color: var(--color-text-subtle);
-    display: block;
-    font-family: var(--font-mono);
-    font-size: 0.8rem;
-    margin: 2rem auto 0;
-    max-width: 46rem;
-    text-decoration: none;
-}
-
-.echo-back:hover {
-    color: var(--color-accent);
-}

JoshHeaps.Net/wwwroot/js/EchoScripts/EchoAudio.js

@@ -1,160 +0,0 @@
-/*
- * Microphone capture and chirp playback, both indexed by AudioContext frame.
- *
- * Frames, not wall-clock: currentTime * sampleRate is exactly the frame number, so a playback
- * scheduled at an audio-clock time converts directly into a position in the recording. Nothing here
- * depends on a timer firing on schedule, which matters because a hidden tab's timers are throttled
- * to about once a second and its chirp would land in another device's slot.
- */
-const EchoAudio = {
-    TARGET_SAMPLE_RATE: 48000,
-    RING_SECONDS: 20,
-    BLUETOOTH_HINTS: /bluetooth|airpod|hands-?free|headset|\bbt\b|wireless/i,
-
-    context: null,
-    stream: null,
-    capture: null,
-    ring: null,
-    highestFrame: 0,
-    peakAmplitude: 0,
-    warnings: [],
-    onSamples: null,
-
-    async start() {
-        if (this.context) return this.describe();
-
-        this.stream = await navigator.mediaDevices.getUserMedia({
-            // Echo cancellation exists to delete sounds this device just played, which is exactly
-            // the measurement. Gain control and noise suppression distort the chirp's envelope.
-            audio: {
-                echoCancellation: false,
-                noiseSuppression: false,
-                autoGainControl: false,
-                channelCount: 1
-            }
-        });
-
-        this.context = new AudioContext({ sampleRate: this.TARGET_SAMPLE_RATE, latencyHint: "interactive" });
-        await this.context.audioWorklet.addModule("/js/EchoScripts/EchoCaptureProcessor.js");
-        await this.context.resume();
-
-        this.ring = new Float32Array(Math.ceil(this.context.sampleRate * this.RING_SECONDS));
-        this.attachCapture();
-        this.warnings = this.inspectDevice();
-
-        return this.describe();
-    },
-
-    attachCapture() {
-        const source = this.context.createMediaStreamSource(this.stream);
-        this.capture = new AudioWorkletNode(this.context, "echo-capture", { numberOfOutputs: 0 });
-        this.capture.port.onmessage = ({ data }) => this.write(data.frame, data.samples);
-        source.connect(this.capture);
-        return this.capture;
-    },
-
-    write(frame, samples) {
-        const capacity = this.ring.length;
-        let loudest = 0;
-
-        for (let i = 0; i < samples.length; i++) {
-            this.ring[(frame + i) % capacity] = samples[i];
-            loudest = Math.max(loudest, Math.abs(samples[i]));
-        }
-
-        this.peakAmplitude = Math.max(this.peakAmplitude * 0.95, loudest);
-        this.highestFrame = Math.max(this.highestFrame, frame + samples.length);
-        this.onSamples?.(this.highestFrame);
-        return this.highestFrame;
-    },
-
-    /** The recording position for an AudioContext time. Exact: currentTime * sampleRate is a frame. */
-    frameAt(contextTime) {
-        return Math.round(contextTime * this.context.sampleRate);
-    },
-
-    /** Copy an absolute frame range out of the ring, or null if it is not (or no longer) held. */
-    read(startFrame, length) {
-        if (length <= 0) return null;
-        if (startFrame + length > this.highestFrame) return null;
-        if (startFrame < this.highestFrame - this.ring.length) return null;
-
-        const capacity = this.ring.length;
-        const window = new Float32Array(length);
-        for (let i = 0; i < length; i++) window[i] = this.ring[((startFrame + i) % capacity + capacity) % capacity];
-
-        return window;
-    },
-
-    /**
-     * Schedule a chirp on the audio clock and return the frame it was scheduled for. When it
-     * actually leaves the speaker is later by an unknown output latency and does not need to be
-     * known — it is recovered from the recording of it.
-     */
-    play(chirp, atContextTime, gain = 0.5) {
-        const when = Math.max(atContextTime, this.context.currentTime);
-        const buffer = this.context.createBuffer(1, chirp.length, this.context.sampleRate);
-        buffer.copyToChannel(chirp, 0);
-
-        const source = this.context.createBufferSource();
-        const volume = this.context.createGain();
-        volume.gain.value = gain;
-        source.buffer = buffer;
-        source.connect(volume).connect(this.context.destination);
-        source.start(when);
-
-        return this.frameAt(when);
-    },
-
-    /** How far behind the audio clock the main thread's view of the recording is running. */
-    captureLagSeconds() {
-        return this.context.currentTime - this.highestFrame / this.context.sampleRate;
-    },
-
-    /** Reported output latency, which bounds how late a scheduled chirp can reach the microphone. */
-    outputLatencySeconds() {
-        return (this.context.outputLatency || 0) + (this.context.baseLatency || 0);
-    },
-
-    inspectDevice() {
-        const warnings = [];
-        const track = this.stream.getAudioTracks()[0];
-        const settings = track?.getSettings() ?? {};
-
-        if (this.context.sampleRate !== this.TARGET_SAMPLE_RATE)
-            warnings.push(`Running at ${this.context.sampleRate}Hz instead of 48000Hz — ranges stay correct but resolution drops.`);
-
-        if (this.BLUETOOTH_HINTS.test(track?.label ?? ""))
-            warnings.push("This looks like a Bluetooth microphone. Bluetooth resamples and re-times the stream, which breaks the measurement — switch to the built-in speaker and microphone.");
-
-        for (const [name, label] of [["echoCancellation", "Echo cancellation"], ["autoGainControl", "Auto gain"], ["noiseSuppression", "Noise suppression"]])
-            if (settings[name] === true) warnings.push(`${label} could not be turned off on this device — the measurement will be unreliable.`);
-
-        return warnings;
-    },
-
-    describe() {
-        const track = this.stream.getAudioTracks()[0];
-
-        return {
-            sampleRate: this.context.sampleRate,
-            label: track?.label ?? "microphone",
-            outputLatencyMs: Math.round(this.outputLatencySeconds() * 1000),
-            warnings: this.warnings
-        };
-    },
-
-    async stop() {
-        this.stream?.getTracks().forEach(track => track.stop());
-        await this.context?.close();
-        this.context = null;
-        this.stream = null;
-        this.capture = null;
-        this.ring = null;
-        this.highestFrame = 0;
-        this.onSamples = null;
-        return true;
-    }
-};
-
-if (typeof window !== "undefined") window.EchoAudio = EchoAudio;

JoshHeaps.Net/wwwroot/js/EchoScripts/EchoCaptureProcessor.js

@@ -1,39 +0,0 @@
-/*
- * Capture worklet. Every block is tagged with the AudioContext frame it started at, which makes the
- * context's own clock the index for all captured audio: a scheduled playback time converts to a
- * recording position exactly, with no dependence on when the main thread got round to noticing.
- *
- * A worklet rather than ScriptProcessorNode because a dropped buffer would break the continuity
- * that the sample count depends on.
- */
-const BLOCK_SAMPLES = 2048;
-
-class EchoCaptureProcessor extends AudioWorkletProcessor {
-    constructor() {
-        super();
-        this.block = new Float32Array(BLOCK_SAMPLES);
-        this.filled = 0;
-        this.blockStartFrame = 0;
-    }
-
-    process(inputs) {
-        const channel = inputs[0]?.[0];
-        if (!channel) return true;
-
-        for (let i = 0; i < channel.length; i++) {
-            if (this.filled === 0) this.blockStartFrame = currentFrame + i;
-            this.block[this.filled++] = channel[i];
-            if (this.filled === BLOCK_SAMPLES) this.flush();
-        }
-
-        return true;
-    }
-
-    flush() {
-        const samples = this.block.slice(0, this.filled);
-        this.port.postMessage({ frame: this.blockStartFrame, samples }, [samples.buffer]);
-        this.filled = 0;
-    }
-}
-
-registerProcessor("echo-capture", EchoCaptureProcessor);

JoshHeaps.Net/wwwroot/js/EchoScripts/EchoDsp.js

@@ -1,585 +0,0 @@
-/*
- * Pure signal-processing and geometry for acoustic ranging. No DOM, no Web Audio, no network:
- * everything here is a function of its arguments so the simulator and the tests can drive the
- * exact code the page runs.
- */
-const EchoDsp = {
-    speedOfSound(temperatureCelsius = 20) {
-        return 331.3 + 0.606 * temperatureCelsius;
-    },
-
-    nextPowerOfTwo(value) {
-        let size = 1;
-        while (size < value) size <<= 1;
-        return size;
-    },
-
-    /**
-     * Linear frequency sweep, tapered at both ends. A sweep is used rather than a tone because a
-     * tone's autocorrelation peaks once per period, leaving no unambiguous arrival to measure.
-     */
-    makeChirp({ sampleRate, durationSeconds, startHz, endHz, taperFraction = 0.15 }) {
-        const length = Math.round(sampleRate * durationSeconds);
-        const sweepRate = (endHz - startHz) / durationSeconds;
-        const chirp = new Float32Array(length);
-
-        for (let i = 0; i < length; i++) {
-            const t = i / sampleRate;
-            chirp[i] = Math.sin(2 * Math.PI * (startHz * t + 0.5 * sweepRate * t * t));
-        }
-
-        return this.applyTaper(chirp, taperFraction);
-    },
-
-    applyTaper(signal, fraction) {
-        const edge = Math.max(1, Math.floor(signal.length * fraction));
-
-        for (let i = 0; i < edge; i++) {
-            const window = 0.5 - 0.5 * Math.cos((Math.PI * i) / edge);
-            signal[i] *= window;
-            signal[signal.length - 1 - i] *= window;
-        }
-
-        return signal;
-    },
-
-    twiddles(size) {
-        this._twiddleCache ??= new Map();
-        const cached = this._twiddleCache.get(size);
-        if (cached) return cached;
-
-        const half = size >> 1;
-        const table = { cos: new Float64Array(half), sin: new Float64Array(half) };
-
-        for (let i = 0; i < half; i++) {
-            const angle = (-2 * Math.PI * i) / size;
-            table.cos[i] = Math.cos(angle);
-            table.sin[i] = Math.sin(angle);
-        }
-
-        this._twiddleCache.set(size, table);
-        return table;
-    },
-
-    fft(real, imaginary, inverse = false) {
-        const size = real.length;
-        this.reverseBits(real, imaginary);
-        const { cos, sin } = this.twiddles(size);
-
-        for (let span = 2; span <= size; span <<= 1) {
-            const half = span >> 1;
-            const stride = size / span;
-
-            for (let base = 0; base < size; base += span) {
-                for (let k = 0; k < half; k++) {
-                    const twiddle = k * stride;
-                    const wReal = cos[twiddle];
-                    const wImaginary = inverse ? -sin[twiddle] : sin[twiddle];
-
-                    const lower = base + k;
-                    const upper = lower + half;
-                    const productReal = real[upper] * wReal - imaginary[upper] * wImaginary;
-                    const productImaginary = real[upper] * wImaginary + imaginary[upper] * wReal;
-
-                    real[upper] = real[lower] - productReal;
-                    imaginary[upper] = imaginary[lower] - productImaginary;
-                    real[lower] += productReal;
-                    imaginary[lower] += productImaginary;
-                }
-            }
-        }
-
-        if (!inverse) return { real, imaginary };
-
-        for (let i = 0; i < size; i++) {
-            real[i] /= size;
-            imaginary[i] /= size;
-        }
-
-        return { real, imaginary };
-    },
-
-    reverseBits(real, imaginary) {
-        const size = real.length;
-
-        for (let i = 1, j = 0; i < size; i++) {
-            let bit = size >> 1;
-            for (; j & bit; bit >>= 1) j ^= bit;
-            j ^= bit;
-            if (i >= j) continue;
-
-            [real[i], real[j]] = [real[j], real[i]];
-            [imaginary[i], imaginary[j]] = [imaginary[j], imaginary[i]];
-        }
-
-        return { real, imaginary };
-    },
-
-    /**
-     * Matched-filter envelope of a recording against a template, via FFT cross-correlation.
-     * Negative frequencies are dropped so the result is the analytic envelope rather than a burst
-     * oscillating at the sweep frequency — an oscillating peak defeats sub-sample interpolation
-     * and makes first-arrival detection jitter by half a carrier period.
-     */
-    matchedFilterEnvelope(recording, template) {
-        const size = this.nextPowerOfTwo(recording.length + template.length);
-        const recordingReal = new Float64Array(size);
-        const recordingImaginary = new Float64Array(size);
-        const templateReal = new Float64Array(size);
-        const templateImaginary = new Float64Array(size);
-
-        recordingReal.set(recording);
-        templateReal.set(template);
-        this.fft(recordingReal, recordingImaginary);
-        this.fft(templateReal, templateImaginary);
-
-        const analyticReal = new Float64Array(size);
-        const analyticImaginary = new Float64Array(size);
-        const half = size >> 1;
-
-        for (let i = 0; i <= half; i++) {
-            const gain = i === 0 || i === half ? 1 : 2;
-            analyticReal[i] = gain * (recordingReal[i] * templateReal[i] + recordingImaginary[i] * templateImaginary[i]);
-            analyticImaginary[i] = gain * (recordingImaginary[i] * templateReal[i] - recordingReal[i] * templateImaginary[i]);
-        }
-
-        this.fft(analyticReal, analyticImaginary, true);
-
-        const envelope = new Float32Array(recording.length);
-        for (let i = 0; i < envelope.length; i++)
-            envelope[i] = Math.sqrt(analyticReal[i] * analyticReal[i] + analyticImaginary[i] * analyticImaginary[i]);
-
-        return envelope;
-    },
-
-    maxInRange(values, start, end) {
-        let index = start;
-        let value = -Infinity;
-
-        for (let i = start; i < end; i++) {
-            if (values[i] <= value) continue;
-            value = values[i];
-            index = i;
-        }
-
-        return { index, value };
-    },
-
-    medianInRange(values, start, end, sampleLimit = 2048) {
-        const span = end - start;
-        if (span <= 0) return 0;
-
-        const stride = Math.max(1, Math.floor(span / sampleLimit));
-        const sampled = [];
-        for (let i = start; i < end; i += stride) sampled.push(values[i]);
-
-        sampled.sort((left, right) => left - right);
-        return sampled[sampled.length >> 1];
-    },
-
-    /**
-     * Sub-sample peak position by fitting a parabola through the peak and its neighbours. One
-     * tenth of a sample is 0.7mm of range at 48kHz, so this is most of the accuracy for free.
-     */
-    refinePeakIndex(envelope, index) {
-        if (index <= 0 || index >= envelope.length - 1) return index;
-
-        const before = envelope[index - 1];
-        const peak = envelope[index];
-        const after = envelope[index + 1];
-        const curvature = before - 2 * peak + after;
-        if (curvature === 0) return index;
-
-        const offset = (0.5 * (before - after)) / curvature;
-        return index + Math.max(-1, Math.min(1, offset));
-    },
-
-    /**
-     * First arrival in a window, not the loudest one. A reflection off a wall or table often
-     * comes back louder than the direct path, and only the direct path is the distance.
-     */
-    findFirstPeak(envelope, options = {}) {
-        const start = Math.max(0, Math.floor(options.start ?? 0));
-        const end = Math.min(envelope.length, Math.ceil(options.end ?? envelope.length));
-        if (end - start < 8) return null;
-
-        const loudest = this.maxInRange(envelope, start, end);
-        const noiseFloor = this.medianInRange(envelope, start, end);
-        const snr = noiseFloor > 0 ? loudest.value / noiseFloor : Infinity;
-        if (snr < (options.minSnr ?? 4)) return null;
-
-        // Held above the noise floor so sidelobes cannot trigger it, but well below the loudest
-        // arrival so that a reflection several times louder than the direct path cannot mask it.
-        const threshold = Math.max(
-            noiseFloor * (options.noiseMultiple ?? 6),
-            loudest.value * (options.relativeThreshold ?? 0.15)
-        );
-
-        let crossing = start;
-        while (crossing < end && envelope[crossing] < threshold) crossing++;
-        if (crossing >= end) return null;
-
-        const lobeEnd = Math.min(end, crossing + (options.lobeSamples ?? 64));
-        const arrival = this.maxInRange(envelope, crossing, lobeEnd);
-
-        return { index: this.refinePeakIndex(envelope, arrival.index), amplitude: arrival.value, snr };
-    },
-
-    /**
-     * Locate every chirp of one round in a single device's recording.
-     *
-     * The device's own chirp is the anchor: it is always present and always the loudest thing in
-     * the recording, and its position absorbs this device's own output and input latency. Every
-     * other slot is then searched relative to that anchor, so no clock agreement between devices
-     * is required — only that the chirps stay in their slots.
-     */
-    detectSlotPeaks({
-        envelope,
-        slotCount,
-        slotSamples,
-        ownSlot,
-        ownSearchStart,
-        ownSearchSamples,
-        slotHints = null,
-        peakOptions = {}
-    }) {
-        const own = this.findFirstPeak(envelope, {
-            ...peakOptions,
-            start: ownSearchStart,
-            end: ownSearchStart + ownSearchSamples
-        });
-
-        if (!own) return null;
-
-        const anchor = own.index - ownSlot * slotSamples;
-        const pad = Math.floor(slotSamples * 0.45);
-        const peaks = new Array(slotCount).fill(null);
-        peaks[ownSlot] = own;
-
-        for (let slot = 0; slot < slotCount; slot++) {
-            if (slot === ownSlot) continue;
-
-            const centre = anchor + slot * slotSamples + (slotHints?.[slot] ?? 0);
-            peaks[slot] = this.findFirstPeak(envelope, {
-                ...peakOptions,
-                start: centre - pad,
-                end: centre + pad
-            });
-        }
-
-        return { anchor, peaks };
-    },
-
-    /**
-     * Distance between two devices from four arrival indices, each measured inside the recording
-     * of the device that made it. Clock offset and audio-pipeline latency appear once with each
-     * sign and cancel; the devices' own speaker-to-microphone spacing does not, and is added back.
-     */
-    pairDistance({ a1, a2, b1, b2, sampleRate, sampleRateA, sampleRateB, speedOfSound, epsilonA = 0, epsilonB = 0 }) {
-        // Each interval is converted to seconds in its own device's sample rate before the two are
-        // subtracted: a device that hands back 44100 instead of 48000 would otherwise contribute
-        // its interval in the wrong unit.
-        const intervalA = (a2 - a1) / (sampleRateA ?? sampleRate);
-        const intervalB = (b2 - b1) / (sampleRateB ?? sampleRate);
-        return ((intervalA - intervalB) / 2) * speedOfSound + (epsilonA + epsilonB) / 2;
-    },
-
-    /**
-     * Symmetric distance matrix from one round of reports. Entries stay null where either device
-     * failed to hear one of the four chirps the pair needs.
-     */
-    buildDistanceMatrix(reports, { speedOfSound = 343, maxDistance = 40 } = {}) {
-        const count = reports.length;
-        const matrix = Array.from({ length: count }, () => new Array(count).fill(null));
-
-        for (let i = 0; i < count; i++) {
-            matrix[i][i] = 0;
-
-            for (let j = i + 1; j < count; j++) {
-                const distance = this.distanceBetween(reports[i], reports[j], speedOfSound);
-                if (distance === null || distance < -1 || distance > maxDistance) continue;
-
-                matrix[i][j] = Math.max(0, distance);
-                matrix[j][i] = matrix[i][j];
-            }
-        }
-
-        return matrix;
-    },
-
-    distanceBetween(deviceA, deviceB, speedOfSound) {
-        const a1 = deviceA.peaks[deviceA.slot];
-        const a2 = deviceA.peaks[deviceB.slot];
-        const b1 = deviceB.peaks[deviceA.slot];
-        const b2 = deviceB.peaks[deviceB.slot];
-        if (a1 === null || a2 === null || b1 === null || b2 === null) return null;
-
-        return this.pairDistance({
-            a1,
-            a2,
-            b1,
-            b2,
-            sampleRateA: deviceA.sampleRate,
-            sampleRateB: deviceB.sampleRate,
-            speedOfSound,
-            epsilonA: deviceA.epsilon ?? 0,
-            epsilonB: deviceB.epsilon ?? 0
-        });
-    },
-
-    /**
-     * Largest set of devices linked by measured distances. Anything outside it cannot be placed
-     * relative to the others, and leaving it in makes the completed matrix infinite.
-     */
-    largestConnectedComponent(matrix) {
-        const unvisited = new Set(matrix.map((_, index) => index));
-        let largest = [];
-
-        while (unvisited.size > 0) {
-            const component = [];
-            const queue = [unvisited.values().next().value];
-            unvisited.delete(queue[0]);
-
-            while (queue.length > 0) {
-                const current = queue.pop();
-                component.push(current);
-
-                for (const next of unvisited)
-                    if (matrix[current][next] !== null) {
-                        unvisited.delete(next);
-                        queue.push(next);
-                    }
-            }
-
-            if (component.length > largest.length) largest = component;
-        }
-
-        return largest.sort((left, right) => left - right);
-    },
-
-    /**
-     * Drop devices whose distances are geometrically impossible. One device reporting a bad peak
-     * distorts the whole layout, so the worst triangle-inequality offender is removed and the
-     * check repeated. Below four devices there is no redundancy left and nothing can be checked.
-     */
-    rejectOutliers(matrix, candidates, tolerance = 0.5) {
-        const keep = [...candidates];
-
-        while (keep.length > 3) {
-            const violations = this.countTriangleViolations(matrix, keep, tolerance);
-            const worst = violations.reduce((best, count, index) => (count > violations[best] ? index : best), 0);
-            if (violations[worst] === 0) break;
-
-            keep.splice(worst, 1);
-        }
-
-        return keep;
-    },
-
-    submatrix(matrix, indices) {
-        return indices.map(row => indices.map(column => matrix[row][column]));
-    },
-
-    countTriangleViolations(matrix, keep, tolerance) {
-        const violations = new Array(keep.length).fill(0);
-
-        for (let i = 0; i < keep.length; i++) {
-            for (let j = i + 1; j < keep.length; j++) {
-                for (let k = j + 1; k < keep.length; k++) {
-                    const sides = [matrix[keep[i]][keep[j]], matrix[keep[j]][keep[k]], matrix[keep[i]][keep[k]]];
-                    if (sides.some(side => side === null)) continue;
-
-                    const longest = Math.max(...sides);
-                    const perimeter = sides.reduce((sum, side) => sum + side, 0);
-                    if (longest <= perimeter - longest + tolerance) continue;
-
-                    violations[i]++;
-                    violations[j]++;
-                    violations[k]++;
-                }
-            }
-        }
-
-        return violations;
-    },
-
-    /** Fill gaps with the shortest known path between the two devices so MDS gets a full matrix. */
-    completeMatrix(matrix) {
-        const count = matrix.length;
-        const filled = matrix.map(row => row.map(value => (value === null ? Infinity : value)));
-
-        for (let via = 0; via < count; via++)
-            for (let i = 0; i < count; i++)
-                for (let j = 0; j < count; j++)
-                    filled[i][j] = Math.min(filled[i][j], filled[i][via] + filled[via][j]);
-
-        return filled;
-    },
-
-    /** Jacobi eigendecomposition of a symmetric matrix. Returns eigenvalues and column vectors. */
-    symmetricEigen(matrix, maxSweeps = 100, tolerance = 1e-14) {
-        const count = matrix.length;
-        const working = matrix.map(row => Float64Array.from(row));
-        const vectors = Array.from({ length: count }, (_, i) => {
-            const column = new Float64Array(count);
-            column[i] = 1;
-            return column;
-        });
-
-        for (let sweep = 0; sweep < maxSweeps; sweep++) {
-            if (this.offDiagonalMagnitude(working) < tolerance) break;
-
-            for (let p = 0; p < count - 1; p++)
-                for (let q = p + 1; q < count; q++)
-                    this.rotateOut(working, vectors, p, q);
-        }
-
-        return {
-            values: working.map((row, i) => row[i]),
-            vectors
-        };
-    },
-
-    offDiagonalMagnitude(matrix) {
-        let total = 0;
-
-        for (let i = 0; i < matrix.length; i++)
-            for (let j = i + 1; j < matrix.length; j++) total += matrix[i][j] * matrix[i][j];
-
-        return total;
-    },
-
-    rotateOut(matrix, vectors, p, q) {
-        if (Math.abs(matrix[p][q]) < 1e-300) return matrix;
-
-        const theta = (matrix[q][q] - matrix[p][p]) / (2 * matrix[p][q]);
-        const sign = theta >= 0 ? 1 : -1;
-        const tangent = sign / (Math.abs(theta) + Math.sqrt(theta * theta + 1));
-        const cosine = 1 / Math.sqrt(tangent * tangent + 1);
-        const sine = tangent * cosine;
-        const count = matrix.length;
-
-        for (let k = 0; k < count; k++) {
-            const left = matrix[k][p];
-            const right = matrix[k][q];
-            matrix[k][p] = cosine * left - sine * right;
-            matrix[k][q] = sine * left + cosine * right;
-        }
-
-        for (let k = 0; k < count; k++) {
-            const left = matrix[p][k];
-            const right = matrix[q][k];
-            matrix[p][k] = cosine * left - sine * right;
-            matrix[q][k] = sine * left + cosine * right;
-        }
-
-        for (let k = 0; k < count; k++) {
-            const left = vectors[k][p];
-            const right = vectors[k][q];
-            vectors[k][p] = cosine * left - sine * right;
-            vectors[k][q] = sine * left + cosine * right;
-        }
-
-        return matrix;
-    },
-
-    /**
-     * Classical multidimensional scaling: coordinates whose pairwise distances best reproduce the
-     * matrix. The result is only defined up to rotation, translation and mirroring.
-     */
-    classicalMds(distances, dimensions = 2) {
-        const count = distances.length;
-        const squared = distances.map(row => row.map(value => value * value));
-        const rowMeans = squared.map(row => row.reduce((sum, value) => sum + value, 0) / count);
-        const grandMean = rowMeans.reduce((sum, value) => sum + value, 0) / count;
-
-        const centred = squared.map((row, i) => row.map((value, j) => -0.5 * (value - rowMeans[i] - rowMeans[j] + grandMean)));
-        const { values, vectors } = this.symmetricEigen(centred);
-        const order = values
-            .map((value, index) => ({ value, index }))
-            .sort((left, right) => right.value - left.value)
-            .slice(0, dimensions);
-
-        return Array.from({ length: count }, (_, i) =>
-            order.map(({ value, index }) => vectors[i][index] * Math.sqrt(Math.max(0, value)))
-        );
-    },
-
-    /**
-     * Rotate, mirror and translate a constellation onto a reference layout. Without this, every
-     * solve returns an arbitrary orientation and the display spins and flips between updates.
-     */
-    alignToReference(points, reference) {
-        if (!reference || reference.length !== points.length || points.length === 0) return points;
-
-        const pointCentre = this.centroid(points);
-        const referenceCentre = this.centroid(reference);
-        let best = null;
-
-        for (const mirror of [1, -1]) {
-            const candidate = this.rotateOnto(points, reference, pointCentre, referenceCentre, mirror);
-            if (!best || candidate.residual < best.residual) best = candidate;
-        }
-
-        return best.points;
-    },
-
-    centroid(points) {
-        const sum = points.reduce((total, [x, y]) => [total[0] + x, total[1] + y], [0, 0]);
-        return [sum[0] / points.length, sum[1] / points.length];
-    },
-
-    rotateOnto(points, reference, pointCentre, referenceCentre, mirror) {
-        let sineTerm = 0;
-        let cosineTerm = 0;
-
-        for (let i = 0; i < points.length; i++) {
-            const px = (points[i][0] - pointCentre[0]) * mirror;
-            const py = points[i][1] - pointCentre[1];
-            const qx = reference[i][0] - referenceCentre[0];
-            const qy = reference[i][1] - referenceCentre[1];
-            sineTerm += px * qy - py * qx;
-            cosineTerm += px * qx + py * qy;
-        }
-
-        const angle = Math.atan2(sineTerm, cosineTerm);
-        const cosine = Math.cos(angle);
-        const sine = Math.sin(angle);
-        let residual = 0;
-
-        const aligned = points.map((point, i) => {
-            const px = (point[0] - pointCentre[0]) * mirror;
-            const py = point[1] - pointCentre[1];
-            const x = px * cosine - py * sine + referenceCentre[0];
-            const y = px * sine + py * cosine + referenceCentre[1];
-            residual += (x - reference[i][0]) ** 2 + (y - reference[i][1]) ** 2;
-            return [x, y];
-        });
-
-        return { points: aligned, residual };
-    },
-
-    /**
-     * Full solve for one round: distances, connectivity, outlier rejection, then a constellation
-     * aligned onto the previous frame.
-     *
-     * <c>previousPoints</c> is indexed by report position, with null for devices that were dropped
-     * last round, so alignment survives devices coming and going.
-     */
-    solveRound(reports, { speedOfSound = 343, previousPoints = null, tolerance = 0.5 } = {}) {
-        const matrix = this.buildDistanceMatrix(reports, { speedOfSound });
-        const connected = this.largestConnectedComponent(matrix);
-        const keep = this.rejectOutliers(matrix, connected, tolerance);
-        const points = keep.length >= 2 ? this.classicalMds(this.completeMatrix(this.submatrix(matrix, keep))) : [];
-        const reference = previousPoints ? keep.map(index => previousPoints[index]) : null;
-        const alignable = reference?.length === points.length && reference.every(Boolean);
-
-        return {
-            matrix,
-            keep,
-            points: alignable ? this.alignToReference(points, reference) : points
-        };
-    }
-};
-
-if (typeof window !== "undefined") window.EchoDsp = EchoDsp;

JoshHeaps.Net/wwwroot/js/EchoScripts/EchoSession.js

@@ -1,269 +0,0 @@
-/*
- * Round lifecycle: join a room, chirp when told to, measure every chirp in our own recording, and
- * report the frame indices. Peaks are reported relative to the analysis window rather than to an
- * absolute frame — every measurement is a difference within one device's own recording, so a
- * constant per-device origin cancels.
- *
- * Both the chirp and the analysis are driven by the audio clock rather than by timers: a hidden tab
- * has its timers throttled to roughly once a second, which is long enough to put its chirp in
- * another device's slot and turn the whole round into nonsense.
- */
-const EchoSession = {
-    LEAD_IN_SECONDS: 0.25,
-    TEMPERATURE_CELSIUS: 20,
-    MAX_OUTPUT_LATENCY_SECONDS: 0.35,
-    CHIRP: { durationSeconds: 0.05, startHz: 2000, endHz: 8000 },
-
-    CLOCK_SAMPLES: 5,
-    LATE_TOLERANCE_SECONDS: 0.05,
-
-    connection: null,
-    deviceId: null,
-    roomCode: null,
-    serverOffsetMs: 0,
-    skippedRounds: 0,
-    devices: [],
-    chirp: null,
-    pending: null,
-    lastRound: null,
-    hintsByDevice: {},
-    previousPoints: null,
-    epsilon: 0.08,
-    onUpdate: () => {},
-
-    async join(roomCode, displayName, { onUpdate }) {
-        this.onUpdate = onUpdate ?? this.onUpdate;
-        const audio = await EchoAudio.start();
-        this.chirp = EchoDsp.makeChirp({ sampleRate: audio.sampleRate, ...this.CHIRP });
-        EchoAudio.onSamples = frame => this.analyseIfCaptured(frame);
-
-        this.connection = new signalR.HubConnectionBuilder().withUrl("/echoHub").withAutomaticReconnect().build();
-        this.connection.on("RoomChanged", room => this.handleRoomChanged(room));
-        this.connection.on("RoundStarting", schedule => this.handleRoundStarting(schedule));
-        this.connection.on("RoundComplete", result => this.handleRoundComplete(result));
-        await this.connection.start();
-
-        const joined = await this.connection.invoke("JoinRoom", roomCode, displayName, audio.sampleRate);
-        this.deviceId = joined.deviceId;
-        this.roomCode = joined.roomCode;
-        this.devices = joined.room.devices;
-        this.serverOffsetMs = await this.estimateServerOffset();
-
-        return { ...joined, audio, serverOffsetMs: this.serverOffsetMs };
-    },
-
-    /**
-     * Offset from the server clock, by the usual round-trip midpoint. Only needs to be good enough
-     * to identify which chirp belongs to which slot, which is tens of milliseconds — the ranging
-     * itself never uses a shared clock.
-     */
-    async estimateServerOffset() {
-        const offsets = [];
-
-        for (let attempt = 0; attempt < this.CLOCK_SAMPLES; attempt++) {
-            const sent = Date.now();
-            const serverNow = await this.connection.invoke("ServerTime");
-            const received = Date.now();
-            offsets.push(serverNow - (sent + received) / 2);
-        }
-
-        offsets.sort((left, right) => left - right);
-        return offsets[offsets.length >> 1];
-    },
-
-    serverNowMs() {
-        return Date.now() + this.serverOffsetMs;
-    },
-
-    handleRoomChanged(room) {
-        this.devices = room.devices;
-        this.previousPoints = null;
-        this.hintsByDevice = {};
-        this.onUpdate({ kind: "room", room });
-        return room;
-    },
-
-    /**
-     * Schedule our chirp for our slot on the audio clock, and record which frames this round will
-     * occupy so the analysis can start the moment that audio has actually been captured.
-     */
-    handleRoundStarting(schedule) {
-        const ownSlot = schedule.slotOrder.indexOf(this.deviceId);
-        if (ownSlot < 0 || !EchoAudio.context) return null;
-
-        const sampleRate = EchoAudio.context.sampleRate;
-        const slotSeconds = schedule.slotMilliseconds / 1000;
-        const secondsUntilStart = (schedule.startsAtUnixMs - this.serverNowMs()) / 1000;
-        const roundStartTime = EchoAudio.context.currentTime + secondsUntilStart;
-        const playAtTime = roundStartTime + ownSlot * slotSeconds;
-
-        // Sitting a round out is far better than chirping late: a chirp in the wrong slot is
-        // attributed to the wrong device and ruins the round for everyone, whereas a missing chirp
-        // costs only this pair, this round.
-        if (playAtTime < EchoAudio.context.currentTime - this.LATE_TOLERANCE_SECONDS) {
-            this.skippedRounds++;
-            this.onUpdate({ kind: "skipped", schedule, lateBySeconds: EchoAudio.context.currentTime - playAtTime });
-            return null;
-        }
-
-        const scheduledFrame = EchoAudio.play(this.chirp, playAtTime);
-
-        const round = {
-            schedule,
-            ownSlot,
-            sampleRate,
-            scheduledFrame,
-            slotSamples: Math.round(slotSeconds * sampleRate),
-            leadInSamples: Math.round(this.LEAD_IN_SECONDS * sampleRate),
-            startFrame: EchoAudio.frameAt(roundStartTime),
-            outputLatencyMs: Math.round(EchoAudio.outputLatencySeconds() * 1000),
-            captureLagMs: Math.round(EchoAudio.captureLagSeconds() * 1000)
-        };
-
-        round.windowStart = round.startFrame - round.leadInSamples;
-        round.windowLength =
-            round.leadInSamples +
-            schedule.slotOrder.length * round.slotSamples +
-            Math.round((schedule.tailMilliseconds / 1000) * sampleRate);
-
-        this.pending = round;
-        this.onUpdate({ kind: "roundStarting", round });
-        return round;
-    },
-
-    /**
-     * Run as soon as the round's audio exists in the ring. Driven by captured audio rather than a
-     * timer so a throttled tab still analyses on time.
-     */
-    analyseIfCaptured(highestFrame) {
-        const round = this.pending;
-        if (!round) return null;
-        if (highestFrame < round.windowStart + round.windowLength) return null;
-
-        this.pending = null;
-        return this.analyse(round);
-    },
-
-    analyse(round) {
-        this.lastRound = round;
-        const recording = EchoAudio.read(round.windowStart, round.windowLength);
-        if (!recording) return null;
-
-        const envelope = EchoDsp.matchedFilterEnvelope(recording, this.chirp);
-        const detected = EchoDsp.detectSlotPeaks({
-            envelope,
-            slotCount: round.schedule.slotOrder.length,
-            slotSamples: round.slotSamples,
-            ownSlot: round.ownSlot,
-            // Anchored on the frame the chirp was scheduled for, so the only unknown left is how
-            // long the speaker takes to actually emit it.
-            ownSearchStart: round.scheduledFrame - round.windowStart,
-            ownSearchSamples: Math.round((this.MAX_OUTPUT_LATENCY_SECONDS + this.CHIRP.durationSeconds) * round.sampleRate),
-            slotHints: this.hintsFor(round.schedule)
-        });
-
-        const diagnostics = this.describeRound(round, detected);
-        this.onUpdate({ kind: "envelope", envelope, detected, round, diagnostics });
-        if (!detected) return null;
-
-        this.rememberHints(round.schedule, detected, round.slotSamples);
-        return this.report(round, detected);
-    },
-
-    describeRound(round, detected) {
-        const millisecondsPer = 1000 / round.sampleRate;
-
-        return {
-            captureLagMs: round.captureLagMs,
-            outputLatencyMs: round.outputLatencyMs,
-            serverOffsetMs: Math.round(this.serverOffsetMs),
-            skippedRounds: this.skippedRounds,
-            clipping: EchoAudio.peakAmplitude >= 0.99,
-            inputPeak: Number(EchoAudio.peakAmplitude.toFixed(3)),
-            ownFound: Boolean(detected?.peaks[round.ownSlot]),
-            slots: round.schedule.slotOrder.map((deviceId, slot) => ({
-                deviceId,
-                own: slot === round.ownSlot,
-                residualMs: detected?.peaks[slot]
-                    ? Math.round((detected.peaks[slot].index - (detected.anchor + slot * round.slotSamples)) * millisecondsPer)
-                    : null,
-                snr: detected?.peaks[slot] ? Math.round(detected.peaks[slot].snr) : null
-            }))
-        };
-    },
-
-    report(round, detected) {
-        return this.connection.invoke("ReportRound", {
-            deviceId: this.deviceId,
-            roundId: round.schedule.roundId,
-            slot: round.ownSlot,
-            sampleRate: round.sampleRate,
-            epsilon: this.epsilon,
-            peaks: detected.peaks.map(peak => peak?.index ?? null)
-        });
-    },
-
-    /**
-     * Where each device's chirp actually landed last round, relative to where the slot said it
-     * would. Output latency differs by tens of milliseconds per device and is stable, so carrying
-     * the residual forward keeps the search windows centred instead of merely wide.
-     */
-    rememberHints(schedule, detected, slotSamples) {
-        schedule.slotOrder.forEach((deviceId, slot) => {
-            const peak = detected.peaks[slot];
-            if (!peak) return;
-            this.hintsByDevice[deviceId] = peak.index - (detected.anchor + slot * slotSamples);
-        });
-
-        return this.hintsByDevice;
-    },
-
-    hintsFor(schedule) {
-        return schedule.slotOrder.map(deviceId => this.hintsByDevice[deviceId] ?? 0);
-    },
-
-    handleRoundComplete(result) {
-        const reports = result.reports.map(report => ({ ...report, peaks: report.peaks ?? [] }));
-        const solved = EchoDsp.solveRound(reports, {
-            speedOfSound: EchoDsp.speedOfSound(this.TEMPERATURE_CELSIUS),
-            previousPoints: this.previousPoints
-        });
-
-        this.previousPoints = this.pointsByReportIndex(reports, solved);
-        this.onUpdate({ kind: "solved", result, reports, solved, deviceId: this.deviceId });
-        return solved;
-    },
-
-    pointsByReportIndex(reports, solved) {
-        const points = new Array(reports.length).fill(null);
-        solved.keep.forEach((reportIndex, i) => {
-            points[reportIndex] = solved.points[i];
-        });
-        return points;
-    },
-
-    setEpsilon(metres) {
-        this.epsilon = metres;
-        localStorage.setItem("echo.epsilon", String(metres));
-        return this.epsilon;
-    },
-
-    loadEpsilon() {
-        const stored = Number(localStorage.getItem("echo.epsilon"));
-        this.epsilon = Number.isFinite(stored) && stored > 0 ? stored : 0.08;
-        return this.epsilon;
-    },
-
-    async leave() {
-        await this.connection?.invoke("LeaveRoom").catch(() => {});
-        await this.connection?.stop();
-        await EchoAudio.stop();
-        this.connection = null;
-        this.pending = null;
-        this.previousPoints = null;
-        this.hintsByDevice = {};
-        return true;
-    }
-};
-
-if (typeof window !== "undefined") window.EchoSession = EchoSession;

JoshHeaps.Net/wwwroot/js/EchoScripts/EchoSim.js

@@ -1,213 +0,0 @@
-/*
- * Virtual room for exercising the real ranging pipeline without microphones. Synthesizes what
- * each device would have recorded — propagation delay, reflections, noise, per-device clock offset
- * and unknown output latency — then runs the same EchoDsp code the page runs.
- */
-const EchoSim = {
-    DEFAULTS: {
-        sampleRate: 48000,
-        slotSeconds: 0.4,
-        tailSeconds: 0.5,
-        speedOfSound: 343,
-        noiseAmplitude: 0.01,
-        referenceGain: 0.5,
-        minimumPathMetres: 0.25,
-        maximumOutputLatencySeconds: 0.2,
-        chirp: { durationSeconds: 0.05, startHz: 2000, endHz: 8000 },
-        reflectionsPerPath: 2,
-        reflectionExtraRange: [0.4, 4.0],
-        reflectionGainRange: [0.2, 0.8],
-        seed: 20260730
-    },
-
-    randomGenerator(seed) {
-        let state = seed >>> 0;
-
-        return () => {
-            state = (state + 0x6d2b79f5) >>> 0;
-            let mixed = Math.imul(state ^ (state >>> 15), 1 | state);
-            mixed = (mixed + Math.imul(mixed ^ (mixed >>> 7), 61 | mixed)) ^ mixed;
-            return ((mixed ^ (mixed >>> 14)) >>> 0) / 4294967296;
-        };
-    },
-
-    separation(first, second) {
-        return Math.hypot(first[0] - second[0], first[1] - second[1]);
-    },
-
-    buildConfiguration(overrides = {}) {
-        const config = { ...this.DEFAULTS, ...overrides };
-        const count = config.positions.length;
-
-        config.chirp = { ...this.DEFAULTS.chirp, ...(overrides.chirp ?? {}) };
-        config.epsilon ??= new Array(count).fill(0.05);
-        config.clockOffsets ??= config.positions.map((_, i) => i * 7919);
-        config.outputLatencies ??= config.positions.map((_, i) => 0.02 + 0.03 * i);
-        config.scheduleJitter ??= config.positions.map((_, i) => 0.004 * i);
-        config.reflections ??= this.buildReflectionTable(config);
-        return config;
-    },
-
-    /**
-     * Multipath for every source-to-listener path independently. Giving every path the same echo
-     * would be worthless as a test: an identical bias on all four arrivals cancels out of the
-     * range formula, so a uniform echo model hides exactly the error it is supposed to expose.
-     */
-    buildReflectionTable(config) {
-        const random = this.randomGenerator(config.seed ^ 0x5f3759df);
-        const spread = (range, value) => range[0] + value * (range[1] - range[0]);
-
-        return config.positions.map(() =>
-            config.positions.map(() =>
-                Array.from({ length: config.reflectionsPerPath }, () => ({
-                    extraMetres: spread(config.reflectionExtraRange, random()),
-                    gain: spread(config.reflectionGainRange, random())
-                }))
-            )
-        );
-    },
-
-    reflectionsFor(config, source, listener) {
-        return Array.isArray(config.reflections[0]) ? config.reflections[source][listener] : config.reflections;
-    },
-
-    /** One recording per device, plus the index each device believes it started playing at. */
-    synthesizeRound(config) {
-        const { positions, sampleRate, slotSeconds, tailSeconds } = config;
-        const random = this.randomGenerator(config.seed);
-        const template = EchoDsp.makeChirp({ sampleRate, ...config.chirp });
-        const maximumOffset = Math.max(...config.clockOffsets);
-        const length = Math.ceil((positions.length * slotSeconds + tailSeconds) * sampleRate) + maximumOffset;
-
-        const devices = positions.map((_, index) => ({
-            recording: this.noiseBuffer(length, config.noiseAmplitude, random),
-            ownSearchStart: Math.round((index * slotSeconds + config.scheduleJitter[index]) * sampleRate) + config.clockOffsets[index]
-        }));
-
-        for (let source = 0; source < positions.length; source++)
-            for (let listener = 0; listener < positions.length; listener++)
-                this.mixArrivals(devices[listener].recording, template, config, source, listener);
-
-        return { devices, template };
-    },
-
-    noiseBuffer(length, amplitude, random) {
-        const buffer = new Float32Array(length);
-        for (let i = 0; i < length; i++) buffer[i] = (random() * 2 - 1) * amplitude;
-        return buffer;
-    },
-
-    mixArrivals(recording, template, config, source, listener) {
-        const emissionSeconds =
-            source * config.slotSeconds + config.scheduleJitter[source] + config.outputLatencies[source];
-        const directMetres =
-            source === listener ? config.epsilon[source] : this.separation(config.positions[source], config.positions[listener]);
-
-        const paths = [
-            { metres: directMetres, gain: 1 },
-            ...this.reflectionsFor(config, source, listener).map(({ extraMetres, gain }) => ({
-                metres: directMetres + extraMetres,
-                gain
-            }))
-        ];
-
-        for (const path of paths) {
-            const arrival = emissionSeconds + path.metres / config.speedOfSound;
-            const amplitude =
-                (config.referenceGain / Math.max(path.metres, config.minimumPathMetres)) * path.gain;
-            this.addAt(recording, template, Math.round(arrival * config.sampleRate) + config.clockOffsets[listener], amplitude);
-        }
-
-        return recording;
-    },
-
-    addAt(recording, template, offset, amplitude) {
-        const start = Math.max(0, offset);
-        const end = Math.min(recording.length, offset + template.length);
-
-        for (let i = start; i < end; i++) recording[i] += template[i - offset] * amplitude;
-
-        return recording;
-    },
-
-    /** Run every device's recording through detection and return one report per device. */
-    detectAll({ devices, template }, config) {
-        const slotSamples = Math.round(config.slotSeconds * config.sampleRate);
-        const searchSamples = Math.round(
-            (config.maximumOutputLatencySeconds + config.chirp.durationSeconds + 0.05) * config.sampleRate
-        );
-
-        return devices.map((device, slot) => {
-            const envelope = EchoDsp.matchedFilterEnvelope(device.recording, template);
-            const detected = EchoDsp.detectSlotPeaks({
-                envelope,
-                slotCount: devices.length,
-                slotSamples,
-                ownSlot: slot,
-                ownSearchStart: device.ownSearchStart,
-                ownSearchSamples: searchSamples,
-                peakOptions: config.peakOptions ?? {}
-            });
-
-            return {
-                deviceId: `sim-${slot}`,
-                slot,
-                sampleRate: config.sampleRate,
-                epsilon: config.epsilon[slot],
-                peaks: (detected?.peaks ?? new Array(devices.length).fill(null)).map(peak => peak?.index ?? null)
-            };
-        });
-    },
-
-    /** Synthesize, detect and solve, reporting recovered geometry against the ground truth. */
-    runRound(overrides = {}) {
-        const config = this.buildConfiguration(overrides);
-        const round = this.synthesizeRound(config);
-        const reports = this.detectAll(round, config);
-        const solved = EchoDsp.solveRound(reports, { speedOfSound: config.speedOfSound });
-
-        return {
-            config,
-            reports,
-            ...solved,
-            distanceErrors: this.distanceErrors(solved.matrix, config),
-            positionErrors: this.positionErrors(solved, config)
-        };
-    },
-
-    distanceErrors(matrix, config) {
-        const errors = [];
-
-        for (let i = 0; i < matrix.length; i++)
-            for (let j = i + 1; j < matrix.length; j++) {
-                const truth = this.separation(config.positions[i], config.positions[j]);
-                errors.push({
-                    pair: [i, j],
-                    truth,
-                    measured: matrix[i][j],
-                    error: matrix[i][j] === null ? null : matrix[i][j] - truth
-                });
-            }
-
-        return errors;
-    },
-
-    positionErrors({ keep, points }, config) {
-        if (points.length !== keep.length || points.length < 2) return [];
-
-        const truth = keep.map(index => config.positions[index]);
-        const aligned = EchoDsp.alignToReference(points, truth);
-        return aligned.map((point, i) => this.separation(point, truth[i]));
-    },
-
-    worstDistanceError(result) {
-        const magnitudes = result.distanceErrors.map(({ error }) => (error === null ? Infinity : Math.abs(error)));
-        return magnitudes.length === 0 ? 0 : Math.max(...magnitudes);
-    },
-
-    worstPositionError(result) {
-        return result.positionErrors.length === 0 ? Infinity : Math.max(...result.positionErrors);
-    }
-};
-
-if (typeof window !== "undefined") window.EchoSim = EchoSim;

JoshHeaps.Net/wwwroot/js/EchoScripts/echoMain.js

@@ -1,282 +0,0 @@
-/*
- * Page wiring for /echo. Renders what the session measures: the matched-filter trace with the
- * arrivals it picked, the pairwise ranges, and — while only two devices are present — one large
- * number, because that number is the whole measurement.
- */
-const EchoPage = {
-    HISTORY_LENGTH: 12,
-
-    elements: {},
-    lastSolved: null,
-    lastDiagnostics: null,
-    history: [],
-    roundsSeen: 0,
-
-    start() {
-        this.elements = {
-            room: document.getElementById("echoRoom"),
-            name: document.getElementById("echoName"),
-            join: document.getElementById("echoJoin"),
-            leave: document.getElementById("echoLeave"),
-            status: document.getElementById("echoStatus"),
-            warnings: document.getElementById("echoWarnings"),
-            readout: document.getElementById("echoReadout"),
-            pairs: document.getElementById("echoPairs"),
-            roster: document.getElementById("echoRoster"),
-            trace: document.getElementById("echoTrace"),
-            epsilon: document.getElementById("echoEpsilon"),
-            shareLink: document.getElementById("echoShareLink"),
-            diagnostics: document.getElementById("echoDiagnostics")
-        };
-
-        this.elements.room.value = new URLSearchParams(location.search).get("room") ?? this.randomCode();
-        this.elements.epsilon.value = EchoSession.loadEpsilon();
-        this.elements.epsilon.addEventListener("change", () => this.applyEpsilon());
-        this.elements.join.addEventListener("click", () => this.join());
-        this.elements.leave.addEventListener("click", () => this.leave());
-
-        return this;
-    },
-
-    randomCode() {
-        const alphabet = "ABCDEFGHJKLMNPQRSTUVWXYZ23456789";
-        return Array.from({ length: 4 }, () => alphabet[Math.floor(Math.random() * alphabet.length)]).join("");
-    },
-
-    applyEpsilon() {
-        const metres = Number(this.elements.epsilon.value);
-        if (!Number.isFinite(metres) || metres < 0) return null;
-
-        EchoSession.setEpsilon(metres);
-        return metres;
-    },
-
-    async join() {
-        const roomCode = this.elements.room.value.trim().toUpperCase();
-        if (!roomCode) return null;
-
-        this.setStatus("Requesting the microphone…");
-        this.elements.join.disabled = true;
-
-        try {
-            const joined = await EchoSession.join(roomCode, this.deviceName(), { onUpdate: update => this.handle(update) });
-            this.showJoined(joined);
-            return joined;
-        } catch (error) {
-            this.setStatus(`Could not start: ${error.message}`);
-            this.elements.join.disabled = false;
-            return null;
-        }
-    },
-
-    deviceName() {
-        const typed = this.elements.name.value.trim();
-        if (typed) return typed;
-
-        return /android|iphone|ipad|mobile/i.test(navigator.userAgent) ? "phone" : "laptop";
-    },
-
-    showJoined(joined) {
-        this.elements.leave.hidden = false;
-        this.elements.room.disabled = true;
-        this.elements.name.disabled = true;
-        this.elements.shareLink.textContent = `${location.origin}/echo?room=${joined.roomCode}`;
-        this.elements.shareLink.href = `/echo?room=${joined.roomCode}`;
-        this.renderWarnings(joined.audio);
-        this.renderRoster(joined.room.devices);
-        this.setStatus(`Listening at ${joined.audio.sampleRate}Hz. Open the same room on another device.`);
-        return joined;
-    },
-
-    async leave() {
-        await EchoSession.leave();
-        this.elements.leave.hidden = true;
-        this.elements.join.disabled = false;
-        this.elements.room.disabled = false;
-        this.elements.name.disabled = false;
-        this.setStatus("Left the room.");
-        return true;
-    },
-
-    handle(update) {
-        if (update.kind === "room") return this.renderRoster(update.room.devices);
-        if (update.kind === "envelope") {
-            this.renderDiagnostics(update.diagnostics);
-            return this.renderTrace(update);
-        }
-        if (update.kind === "solved") return this.renderSolved(update);
-        return null;
-    },
-
-    /**
-     * Per-slot residual is the diagnostic that matters: it is how far each chirp landed from where
-     * its slot said it would. Steady residuals mean the arrivals are being attributed correctly;
-     * residuals jumping by more than a slot mean they are not, and every range is then meaningless.
-     */
-    renderDiagnostics(diagnostics) {
-        if (!diagnostics) return null;
-        this.lastDiagnostics = diagnostics;
-
-        const slots = diagnostics.slots
-            .map(slot => {
-                const label = slot.own ? "self" : slot.deviceId;
-                const residual = slot.residualMs === null ? "missed" : `${slot.residualMs > 0 ? "+" : ""}${slot.residualMs}ms`;
-                return `<li class="${slot.residualMs === null ? "echo-missed" : ""}">${label} · ${residual}${slot.snr === null ? "" : ` · snr ${slot.snr}`}</li>`;
-            })
-            .join("");
-
-        this.elements.diagnostics.innerHTML = `
-            <ul class="echo-slots">${slots}</ul>
-            <p class="echo-diag-line">
-                capture lag ${diagnostics.captureLagMs}ms · output latency ${diagnostics.outputLatencyMs}ms ·
-                clock offset ${diagnostics.serverOffsetMs}ms · rounds sat out ${diagnostics.skippedRounds} ·
-                input peak ${diagnostics.inputPeak}${diagnostics.clipping ? " <strong>CLIPPING</strong>" : ""}
-            </p>`;
-
-        return diagnostics;
-    },
-
-    recordHistory(metres) {
-        this.history.push(metres);
-        if (this.history.length > this.HISTORY_LENGTH) this.history.shift();
-
-        const spread = Math.max(...this.history) - Math.min(...this.history);
-        return { spread, count: this.history.length };
-    },
-
-    setStatus(message) {
-        this.elements.status.textContent = message;
-        return message;
-    },
-
-    renderWarnings(audio) {
-        this.elements.warnings.innerHTML = "";
-
-        for (const warning of audio.warnings) {
-            const item = document.createElement("p");
-            item.className = "echo-warning";
-            item.textContent = warning;
-            this.elements.warnings.appendChild(item);
-        }
-
-        return audio.warnings.length;
-    },
-
-    renderRoster(devices) {
-        this.elements.roster.innerHTML = "";
-
-        for (const device of devices) {
-            const row = document.createElement("li");
-            row.className = device.deviceId === EchoSession.deviceId ? "echo-device echo-device-self" : "echo-device";
-            row.textContent = `${device.displayName} · ${device.sampleRate}Hz`;
-            this.elements.roster.appendChild(row);
-        }
-
-        if (devices.length < 2) this.setStatus("Waiting for a second device to join this room.");
-        return devices.length;
-    },
-
-    renderSolved({ result, reports, solved }) {
-        this.roundsSeen++;
-        const raw = EchoDsp.buildDistanceMatrix(
-            reports.map(report => ({ ...report, epsilon: 0 })),
-            { speedOfSound: EchoDsp.speedOfSound(EchoSession.TEMPERATURE_CELSIUS) }
-        );
-
-        this.lastSolved = { result, reports, solved, raw };
-        this.renderReadout(reports, solved, raw);
-        this.renderPairs(reports, solved, raw);
-        this.setStatus(`Round ${this.roundsSeen} · ${reports.length} of ${EchoSession.devices.length} devices reported`);
-        return solved;
-    },
-
-    renderReadout(reports, solved, raw) {
-        const readout = this.elements.readout;
-
-        if (reports.length !== 2 || solved.matrix[0][1] === null) {
-            readout.innerHTML = `<span class="echo-readout-idle">${reports.length < 2 ? "waiting for a pair" : "measuring…"}</span>`;
-            return null;
-        }
-
-        const corrected = solved.matrix[0][1];
-        const { spread, count } = this.recordHistory(corrected);
-        readout.innerHTML = `
-            <span class="echo-metres">${corrected.toFixed(2)}<small>m</small></span>
-            <span class="echo-readout-detail">
-                raw ${raw[0][1].toFixed(3)}m · calibration +${(corrected - raw[0][1]).toFixed(3)}m ·
-                spread over last ${count} ${spread.toFixed(2)}m
-            </span>`;
-
-        return corrected;
-    },
-
-    renderPairs(reports, solved, raw) {
-        const rows = [];
-
-        for (let i = 0; i < reports.length; i++)
-            for (let j = i + 1; j < reports.length; j++) {
-                const dropped = !solved.keep.includes(i) || !solved.keep.includes(j);
-                const measured = solved.matrix[i][j];
-                rows.push(`<tr class="${dropped ? "echo-dropped" : ""}">
-                    <td>${reports[i].deviceId} ↔ ${reports[j].deviceId}</td>
-                    <td>${measured === null ? "—" : measured.toFixed(3) + " m"}</td>
-                    <td>${raw[i][j] === null ? "—" : raw[i][j].toFixed(3) + " m"}</td>
-                </tr>`);
-            }
-
-        this.elements.pairs.innerHTML = rows.length
-            ? `<table><thead><tr><th>pair</th><th>range</th><th>raw</th></tr></thead><tbody>${rows.join("")}</tbody></table>`
-            : "";
-
-        return rows.length;
-    },
-
-    /** The matched-filter trace, with a marker on each arrival the detector accepted. */
-    renderTrace({ envelope, detected, round }) {
-        const canvas = this.elements.trace;
-        const context = canvas.getContext("2d");
-        const width = (canvas.width = canvas.clientWidth);
-        const height = (canvas.height = 160);
-        const peak = EchoDsp.maxInRange(envelope, 0, envelope.length).value || 1;
-
-        context.clearRect(0, 0, width, height);
-        context.strokeStyle = "rgba(9, 255, 0, 0.75)";
-        context.beginPath();
-
-        const bucket = envelope.length / width;
-        for (let x = 0; x < width; x++) {
-            const start = Math.floor(x * bucket);
-            const highest = EchoDsp.maxInRange(envelope, start, Math.min(envelope.length, Math.floor(start + bucket))).value;
-            const y = height - (highest / peak) * (height - 8) - 4;
-            x === 0 ? context.moveTo(x, y) : context.lineTo(x, y);
-        }
-
-        context.stroke();
-        this.drawMarkers(context, detected, round, envelope.length, width, height);
-        return canvas;
-    },
-
-    drawMarkers(context, detected, round, envelopeLength, width, height) {
-        if (!detected) return null;
-
-        context.font = "11px 'Cascadia Code', monospace";
-
-        detected.peaks.forEach((peak, slot) => {
-            if (!peak) return;
-
-            const x = (peak.index / envelopeLength) * width;
-            const own = slot === round.ownSlot;
-            context.strokeStyle = own ? "#5fff5f" : "rgba(255, 255, 255, 0.55)";
-            context.fillStyle = context.strokeStyle;
-            context.beginPath();
-            context.moveTo(x, 0);
-            context.lineTo(x, height);
-            context.stroke();
-            context.fillText(own ? `self (${slot})` : `slot ${slot}`, x + 4, 14 + slot * 13);
-        });
-
-        return detected.peaks.length;
-    }
-};
-
-document.addEventListener("DOMContentLoaded", () => EchoPage.start());

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 +1,70 @@
+// 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) ? `"${str.replace(/"/g, '""')}"` : str;
+    },
+
+    formatTimestamp(timestamp) {
+        try {
+            return new Date(timestamp).toLocaleString();
+        } catch {
+            return "";
+        }
+    },
+
+    toCsv(handHistory, standings = []) {
+        const rows = [["Hand #", "Time", "Pot", "Payouts"]];
+        // handHistory is stored newest-first; the export reads better oldest-first.
+        [...handHistory].reverse().forEach(entry => {
+            const payouts = (entry.payouts || [])
+                .map(p => `${p.label}: ${Money.format(p.amount)}`)
+                .join("; ");
+            rows.push([
+                entry.handNumber,
+                this.formatTimestamp(entry.timestamp),
+                Money.format(entry.pot),
+                payouts,
+            ]);
+        });
+
+        // The settle-up numbers go in the same file as the hands they came from, so a
+        // dealer handing over one export isn't asked for a second one at cash-out.
+        if (standings.length > 0) {
+            rows.push([]);
+            rows.push(["Session Standings"]);
+            rows.push(["Player", "Paid In", "Won", "Net"]);
+            standings.forEach(row => {
+                rows.push([row.name, Money.format(row.in), Money.format(row.won), Money.formatSigned(row.net)]);
+            });
+        }
+
+        return rows.map(row => row.map(f => this.csvField(f)).join(",")).join("\r\n");
+    },
+
+    fileName() {
+        const now = new Date();
+        const pad = n => String(n).padStart(2, "0");
+        const stamp = `${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 +1,138 @@
+document.addEventListener("DOMContentLoaded", () => {
+    const state = HoldemState.load();
+
+    const hooks = {
+        save: s => HoldemState.save(s),
+        rerender: () => Render.renderAll(),
+    };
+
+    Render.mount(state, hooks);
+
+    // 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 = JSON.parse(JSON.stringify(state));
+        mutate();
+        hooks.save(state);
+        Render.renderAll();
+
+        Toast.show(message, {
+            actionLabel: "Undo",
+            onAction: () => {
+                Object.keys(state).forEach(key => delete state[key]);
+                Object.assign(state, snapshot);
+                hooks.save(state);
+                Render.renderAll();
+                Toast.show("Undone.", { duration: 2500 });
+            },
+        });
+    };
+
+    document.getElementById("seatCountInput").addEventListener("change", e => {
+        HoldemState.resizeSeats(state, Number(e.target.value));
+        hooks.save(state);
+        Render.renderAll();
+    });
+
+    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", () => {
+        // 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}`;
+
+        runUndoable(`Next hand — ${where}. Cards and chip counts cleared.`, () =>
+            HoldemState.startNextHand(state)
+        );
+    });
+
+    document.getElementById("resetTableBtn").addEventListener("click", async () => {
+        const ok = await Dialog.confirm({
+            title: "Reset the whole table?",
+            message: "Every seat, chip colour and note goes back to defaults. The hand history and session standings are cleared too.",
+            confirmLabel: "Reset table",
+            danger: true,
+        });
+        if (!ok) return;
+
+        HoldemState.clear();
+        Object.assign(state, HoldemState.createDefault());
+        Render.mount(state, hooks);
+        Toast.show("Table reset.", { duration: 2500 });
+    });
+
+    document.getElementById("resolvePotBtn").addEventListener("click", () => {
+        PotWizard.open(state, payouts => {
+            const paid = payouts.map(p => `${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);
+                HoldemState.startNextHand(state);
+            });
+        });
+    });
+
+    document.getElementById("closeSeatEditorBtn").addEventListener("click", () => Render.closeSeatEditor());
+
+    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/money.js

@@ -0,0 +1,22 @@
+// Shared money formatting for every casino surface. Kept apart from the table's
+// rendering so the quick-split calculator can pull in the formatter without dragging
+// the whole seat/chip UI along with it.
+const Money = {
+    format(amount) {
+        const value = Number(amount) || 0;
+        return `$${value.toLocaleString(undefined, { minimumFractionDigits: 2, maximumFractionDigits: 2 })}`;
+    },
+
+    // "+$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 +1,78 @@
+// 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: 0.004,
+
+    // 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);
+    },
+
+    // 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: Math.round((e.remaining - used) * 100) / 100 };
+        });
+
+        payoutPool = Math.round(payoutPool * 100) / 100;
+        const baseShareCents = Math.floor((payoutPool * 100) / winners.length);
+        let leftoverCents = Math.round(payoutPool * 100) - 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: w.amountCents / 100 }));
+        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 +1,201 @@
+// 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.entries = PotCalculator.buildEntries(
+            players.map(p => ({
+                id: p.id,
+                contribution: HoldemState.computeContribution(p, state.chipLegend, state.basePotAmount),
+                folded: p.folded,
+            }))
+        );
+        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).join(" ");
+        return cards ? `${name} (${cards})` : name;
+    },
+
+    addToTotal(id, amount) {
+        this.totals.set(id, (this.totals.get(id) || 0) + amount);
+    },
+
+    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 = "";
+        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";
+            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>${Money.format(remaining)}</strong> unassigned — who's next best?`;
+        round.appendChild(prompt);
+
+        const choices = document.createElement("div");
+        choices.className = "potWizardChoices";
+        contenders.forEach(c => {
+            const label = document.createElement("label");
+            label.className = "potWizardChoice";
+            const checkbox = document.createElement("input");
+            checkbox.type = "checkbox";
+            checkbox.value = c.id;
+            const text = document.createElement("span");
+            text.textContent = `${this.playerLabelById.get(c.id)} — up to ${Money.format(c.remaining)}`;
+            label.appendChild(checkbox);
+            label.appendChild(text);
+            choices.appendChild(label);
+        });
+        round.appendChild(choices);
+
+        const hint = document.createElement("p");
+        hint.className = "fieldHint";
+        hint.textContent = "Check more than one to split the pot on a tie.";
+        round.appendChild(hint);
+
+        const confirmBtn = document.createElement("button");
+        confirmBtn.className = "holdemBtn holdemBtnAccent";
+        confirmBtn.textContent = "Confirm Winner(s)";
+        confirmBtn.addEventListener("click", () => {
+            const selected = Array.from(choices.querySelectorAll("input:checked")).map(i => i.value);
+            if (selected.length === 0) return;
+            const result = PotCalculator.resolveRound(this.entries, selected);
+            this.recordRound(result);
+            this.entries = result.updatedEntries;
+            this.renderStep();
+        });
+        round.appendChild(confirmBtn);
+
+        body.appendChild(round);
+    },
+
+    recordRound(result) {
+        result.perWinner.forEach(w => this.addToTotal(w.id, w.amount));
+        this.log.push({
+            amount: result.payoutPool,
+            winners: result.perWinner.map(w => `${this.playerLabelById.get(w.id)} (${Money.format(w.amount)})`),
+        });
+    },
+
+    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)} → ${entry.winners.join(", ")}`;
+            wrap.appendChild(line);
+        });
+        return wrap;
+    },
+
+    renderSummary() {
+        const wrap = document.createElement("div");
+        wrap.className = "potWizardSummary";
+
+        const heading = document.createElement("h3");
+        heading.textContent = "Final Payouts";
+        wrap.appendChild(heading);
+
+        if (this.totals.size === 0) {
+            const empty = document.createElement("p");
+            empty.className = "fieldHint";
+            empty.textContent = "Nobody has money in this pot yet — mark seats \"In hand\" and set contributions first.";
+            wrap.appendChild(empty);
+        } else {
+            const list = document.createElement("ul");
+            for (const [id, amount] of this.totals.entries()) {
+                const li = document.createElement("li");
+                li.textContent = `${this.playerLabelById.get(id)} — ${Money.format(amount)}`;
+                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);
+
+        const closeBtn = document.createElement("button");
+        closeBtn.className = "holdemBtn holdemBtnGhost";
+        closeBtn.textContent = "Close";
+        closeBtn.addEventListener("click", () => this.close());
+        actions.appendChild(closeBtn);
+
+        wrap.appendChild(actions);
+        return wrap;
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = PotWizard;
+}

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

@@ -0,0 +1,166 @@
+// 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,
+
+    mount() {
+        this.potInput = document.getElementById("potInput");
+        this.clearPotBtn = document.getElementById("clearPotBtn");
+
+        this.renderWayChoices();
+        this.renderChipChoices();
+
+        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();
+                })
+            );
+        });
+    },
+
+    update() {
+        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 +1,433 @@
+// 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;
+        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();
+    },
+
+    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;
+    },
+
+    renderTableHint() {
+        const hint = document.getElementById("tableHint");
+        hint.textContent = this.state.dedicatedDealer
+            ? "Drag a seat onto another seat to swap players."
+            : "Drag a seat onto another seat to swap players. Click the dealer chip on a seat to make it the button.";
+    },
+
+    renderNotes() {
+        const notesEl = document.getElementById("tableNotes");
+        if (document.activeElement !== notesEl) notesEl.value = this.state.notes || "";
+    },
+
+    updatePotBadge() {
+        const total = HoldemState.totalPot(this.state);
+        document.getElementById("potBadgeAmount").textContent = Money.format(total);
+    },
+
+    // ---- Seats around the table (compact pucks) ----
+
+    seatPosition(index, count) {
+        const angle = -90 + (360 / count) * index;
+        const radians = (angle * Math.PI) / 180;
+        const rx = 44;
+        const ry = 42;
+        const left = 50 + rx * Math.cos(radians);
+        const top = 50 + ry * Math.sin(radians);
+        return { left, top };
+    },
+
+    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 } = 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);
+
+            node.querySelector(".seatChairNumber").textContent = index + 1;
+
+            const dealerChip = node.querySelector(".dealerChip");
+            dealerChip.classList.toggle("active", index === dealerIndex);
+            dealerChip.classList.toggle("hidden", !!this.state.dedicatedDealer);
+            dealerChip.addEventListener("click", e => {
+                e.stopPropagation();
+                this.state.dealerSeatIndex = index;
+                this.hooks.save(this.state);
+                this.renderSeats();
+            });
+
+            node.querySelector(".sbBadge").classList.toggle("visible", index === sbIndex);
+            node.querySelector(".bbBadge").classList.toggle("visible", index === bbIndex);
+
+            this.updatePuckContent(node, player, index);
+            node.classList.toggle("seatSelected", index === this.selectedSeatIndex);
+
+            node.addEventListener("click", () => {
+                // 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.
+                this.selectedSeatIndex = this.selectedSeatIndex === index ? null : index;
+                this.renderSeats();
+                this.renderSeatEditor();
+            });
+
+            this.wireDragAndDrop(node, index);
+
+            layer.appendChild(node);
+        });
+    },
+
+    isRedSuit(card) {
+        return /[HD]$/i.test(card || "");
+    },
+
+    updatePuckContent(node, player, index) {
+        node.querySelector(".seatPuckName").textContent = player.name && player.name.trim() ? player.name.trim() : "";
+        const cardsEl = node.querySelector(".seatPuckCards");
+        cardsEl.innerHTML = "";
+        (player.cards || []).filter(Boolean).forEach((card, i) => {
+            if (i > 0) cardsEl.appendChild(document.createTextNode(" "));
+            const span = document.createElement("span");
+            if (this.isRedSuit(card)) span.className = "cardRed";
+            span.textContent = card;
+            cardsEl.appendChild(span);
+        });
+        const total = HoldemState.computeContribution(player, this.state.chipLegend, this.state.basePotAmount);
+        node.querySelector(".seatPuckTotal").textContent = total > 0 ? Money.format(total) : "";
+        node.classList.toggle("seatInactive", !player.inHand);
+        node.classList.toggle("seatFolded", player.folded);
+    },
+
+    // Cheaper than a full renderSeats() — used after edits so the seat editor's inputs
+    // (which live in a separate panel) never lose focus.
+    refreshPuck(index) {
+        const node = document.querySelector(`.seat[data-seat-index="${index}"]`);
+        if (node) this.updatePuckContent(node, this.state.seats[index], index);
+    },
+
+    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 card1 = form.querySelector(".card1Input");
+        const card2 = form.querySelector(".card2Input");
+        card1.value = player.cards[0] || "";
+        card2.value = player.cards[1] || "";
+        [card1, card2].forEach((input, cardIdx) => {
+            input.classList.toggle("cardRed", this.isRedSuit(input.value));
+            input.addEventListener("input", () => {
+                input.value = input.value.toUpperCase();
+                input.classList.toggle("cardRed", this.isRedSuit(input.value));
+                player.cards[cardIdx] = input.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);
+        });
+    },
+
+    // ---- 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);
+
+            list.appendChild(node);
+        });
+    },
+
+    // ---- Hand counter + history ----
+
+    formatHandTime(timestamp) {
+        try {
+            return new Date(timestamp).toLocaleTimeString(undefined, { hour: "2-digit", minute: "2-digit" });
+        } catch {
+            return "";
+        }
+    },
+
+    renderHandHistory() {
+        document.getElementById("handCounterBadge").textContent = `Hand #${this.state.handNumber || 1}`;
+
+        const list = document.getElementById("handHistoryList");
+        const emptyHint = document.getElementById("handHistoryEmptyHint");
+        const history = this.state.handHistory || [];
+        list.innerHTML = "";
+        emptyHint.hidden = history.length > 0;
+        document.getElementById("exportHistoryBtn").disabled = history.length === 0;
+
+        const template = document.getElementById("handHistoryRowTemplate");
+        history.forEach(entry => {
+            const row = template.content.firstElementChild.cloneNode(true);
+            row.querySelector(".handHistoryHandNumber").textContent = `Hand #${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(", ");
+
+            list.appendChild(row);
+        });
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = { Render };
+}

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 Math.round((Number(amount) || 0) * 100);
+    },
+
+    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 (
+            Math.round(result.each * 100) * result.players +
+            Math.round(result.chip * 100) * result.oddChips +
+            Math.round(result.dust * 100)
+        ) / 100;
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = SplitCalculator;
+}

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

@@ -0,0 +1,224 @@
+// 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: [],
+        };
+    },
+
+    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: [],
+        };
+    },
+
+    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 = [];
+            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.
+    computeContribution(player, chipLegend, basePotAmount) {
+        if (!player.inHand) return 0;
+
+        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;
+
+        const base = Number(basePotAmount);
+        return Number.isNaN(base) ? 0 : Math.max(0, base);
+    },
+
+    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;
+    },
+
+    advanceButton(state) {
+        state.dealerSeatIndex = this.nextSeatIndex(state, state.dealerSeatIndex, 1);
+    },
+
+    getBlindSeats(state) {
+        const sbIndex = this.nextSeatIndex(state, state.dealerSeatIndex, 1);
+        const bbIndex = this.nextSeatIndex(state, state.dealerSeatIndex, 2);
+        return { dealerIndex: state.dealerSeatIndex, sbIndex, bbIndex };
+    },
+
+    startNextHand(state) {
+        this.advanceButton(state);
+        state.seats.forEach(p => {
+            p.folded = false;
+            p.cards = ["", ""];
+            p.chipCounts = {};
+            p.amountOverride = null;
+        });
+    },
+
+    // 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);
+            });
+        });
+
+        return Array.from(totals.values())
+            .map(t => ({
+                ...t,
+                in: Math.round(t.in * 100) / 100,
+                won: Math.round(t.won * 100) / 100,
+                net: Math.round((t.won - t.in) * 100) / 100,
+            }))
+            .sort((a, b) => b.net - a.net);
+    },
+};
+
+if (typeof module !== "undefined" && module.exports) {
+    module.exports = HoldemState;
+}

native/chess_engine/include/chess_engine.h

@@ -103,9 +103,13 @@ 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: rewards the winner's
- * occupied squares / features and punishes the loser's, scaled by `weight` (e.g. 0.5 for a
- * material-imbalance draw). winner: 0 = white, 1 = black. */
+/* 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

native/chess_engine/src/chess_engine.cpp

@@ -26,6 +26,7 @@
 #include <cstdlib>
 #include <cstring>
 #include <fstream>
+#include <iomanip>
 #include <mutex>
 #include <new>
 #include <string>
@@ -115,11 +116,25 @@ struct ChessEngine {
 /* 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). */
+ * 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;
@@ -127,13 +142,15 @@ 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) and each side's feature
- * activations; trainer_apply turns the totals into weight nudges. Squares are white-relative
+ * 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;
 };
 
@@ -172,9 +189,12 @@ static int parse_variant(const char* options) {
 }
 
 /* On-disk format: 6*64 mg ints (PAWN..KING, squares 0..63), then 6*64 eg ints, then
- * FEATURE_NB feature ints, 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".
- * Caller holds g_weightsMutex. */
+ * 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 */
 
@@ -190,9 +210,29 @@ static void load_global_weights(const char* path) {
             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. Caller holds the lock. */
+/* 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);
@@ -203,6 +243,18 @@ static void save_global_weights() {
     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
@@ -382,13 +434,18 @@ static int evaluate(const chess::Position& pos) {
  * 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 rates and clamps. Squares accumulate occupancy (plies on a
- * square, summed); features accumulate normalized per-ply activation (averaged, divided by a
- * nominal scale so high-magnitude mobility doesn't dwarf the small pawn-structure terms). */
-static constexpr double SQUARE_LR  = 0.5;
-static constexpr int    SQ_CLAMP   = 250;
-static constexpr double FEAT_LR    = 2.0;
-static constexpr int    FEAT_CLAMP = 500;
+/* 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
@@ -823,7 +880,9 @@ CHESS_API void CHESS_CALL trainer_record(TrainerHandle t, const char* fen) {
     chess::Position pos = chess::Position::from_fen(fen);
     double phase = game_phase(pos);
 
-    /* Per-square occupancy, split into midgame/endgame by phase, white-relative. */
+    /* 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);
@@ -833,6 +892,7 @@ CHESS_API void CHESS_CALL trainer_record(TrainerHandle t, const char* fen) {
         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. */
@@ -847,34 +907,66 @@ CHESS_API void CHESS_CALL trainer_record(TrainerHandle t, const char* fen) {
     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) return;
+    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 (reward, +1); pass 1 = loser (punish, -1). */
+    /* 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);
-        int sign = pass == 0 ? 1 : -1;
+        double advantage = pass == 0 ? advantageMag : -advantageMag;
 
         for (int pt = chess::PAWN; pt <= chess::KING; ++pt)
             for (int sq = 0; sq < 64; ++sq) {
-                if (t->mgOcc[side][pt][sq] != 0.0) {
-                    int d = sign * int(std::lround(SQUARE_LR * t->mgOcc[side][pt][sq] * weight));
-                    g_weights.mg[pt][sq] = std::clamp(g_weights.mg[pt][sq] + d, -SQ_CLAMP, SQ_CLAMP);
+                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]));
                 }
-                if (t->egOcc[side][pt][sq] != 0.0) {
-                    int d = sign * int(std::lround(SQUARE_LR * t->egOcc[side][pt][sq] * weight));
-                    g_weights.eg[pt][sq] = std::clamp(g_weights.eg[pt][sq] + d, -SQ_CLAMP, SQ_CLAMP);
+                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]));
                 }
             }
 
-        if (t->plies > 0)
-            for (int i = 0; i < FEATURE_NB; ++i) {
-                double avg = t->featAcc[side][i] / t->plies;        /* per-ply average, normalized */
-                int d = sign * int(std::lround(FEAT_LR * (avg / FEAT_SCALE[i]) * weight));
-                g_weights.featW[i] = std::clamp(g_weights.featW[i] + d, -FEAT_CLAMP, FEAT_CLAMP);
-            }
+        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();