From 44fbd79c04e3479e963e4ebcc3870412b79eef3a Mon Sep 17 00:00:00 2001
From: DualFroz <me@dualfroz.com>
Date: Wed, 26 Aug 2026 20:28:22 +0200
Subject: [PATCH] feat(replay): add script command types

---
 src/Chip8.Replay/ScriptCommand.cs | 201 ++++++++++++++++++++++++++++++
 1 file changed, 201 insertions(+)
 create mode 100644 src/Chip8.Replay/ScriptCommand.cs

diff --git a/src/Chip8.Replay/ScriptCommand.cs b/src/Chip8.Replay/ScriptCommand.cs
new file mode 100644
index 0000000..80b60ce
--- /dev/null
+++ b/src/Chip8.Replay/ScriptCommand.cs
@@ -0,0 +1,201 @@
+using Chip8.Core;
+
+namespace Chip8.Replay;
+
+public enum CompareOp
+{
+    Equal,
+    NotEqual,
+}
+
+public abstract class ScriptCommand
+{
+    public int sourceLine { get; internal set; }
+
+    public abstract void execute(ScriptRunner runner);
+
+    public abstract string describe();
+
+    public override string ToString() => describe();
+}
+
+public sealed class PressCommand : ScriptCommand
+{
+    public int key { get; }
+
+    public PressCommand(int key)
+    {
+        this.key = key;
+    }
+
+    public override void execute(ScriptRunner runner) => runner.press(key);
+
+    public override string describe() => "press " + key.ToString("X1");
+}
+
+public sealed class ReleaseCommand : ScriptCommand
+{
+    public int key { get; }
+
+    public ReleaseCommand(int key)
+    {
+        this.key = key;
+    }
+
+    public override void execute(ScriptRunner runner) => runner.release(key);
+
+    public override string describe() => "release " + key.ToString("X1");
+}
+
+public sealed class HoldCommand : ScriptCommand
+{
+    public int key { get; }
+    public int frames { get; }
+
+    public HoldCommand(int key, int frames)
+    {
+        this.key = key;
+        this.frames = frames;
+    }
+
+    public override void execute(ScriptRunner runner)
+    {
+        runner.press(key);
+        runner.advanceFrames(frames);
+        runner.release(key);
+    }
+
+    public override string describe() => "hold " + key.ToString("X1") + " for " + frames;
+}
+
+public sealed class WaitCommand : ScriptCommand
+{
+    public int frames { get; }
+
+    public WaitCommand(int frames)
+    {
+        this.frames = frames;
+    }
+
+    public override void execute(ScriptRunner runner) => runner.advanceFrames(frames);
+
+    public override string describe() => "wait " + frames;
+}
+
+public sealed class FrameCommand : ScriptCommand
+{
+    public int targetFrame { get; }
+    public ScriptCommand inner { get; }
+
+    public FrameCommand(int targetFrame, ScriptCommand inner)
+    {
+        this.targetFrame = targetFrame;
+        this.inner = inner;
+    }
+
+    public override void execute(ScriptRunner runner)
+    {
+        runner.advanceTo(targetFrame);
+        inner.execute(runner);
+    }
+
+    public override string describe() => "frame " + targetFrame + ": " + inner.describe();
+}
+
+public sealed class AssertRegisterCommand : ScriptCommand
+{
+    public int register { get; }
+    public CompareOp op { get; }
+    public int expected { get; }
+
+    public AssertRegisterCommand(int register, CompareOp op, int expected)
+    {
+        this.register = register;
+        this.op = op;
+        this.expected = expected;
+    }
+
+    public override void execute(ScriptRunner runner)
+    {
+        int actual = runner.machine.v[register];
+        runner.checkCompare(this, "V" + register.ToString("X1"), actual, op, expected);
+    }
+
+    public override string describe() =>
+        "assert v" + register.ToString("X1") + " " + CompareOps.symbol(op) + " " + expected;
+}
+
+public sealed class AssertIndexCommand : ScriptCommand
+{
+    public CompareOp op { get; }
+    public int expected { get; }
+
+    public AssertIndexCommand(CompareOp op, int expected)
+    {
+        this.op = op;
+        this.expected = expected;
+    }
+
+    public override void execute(ScriptRunner runner) =>
+        runner.checkCompare(this, "I", runner.machine.i, op, expected);
+
+    public override string describe() => "assert i " + CompareOps.symbol(op) + " " + expected;
+}
+
+public sealed class AssertPcCommand : ScriptCommand
+{
+    public CompareOp op { get; }
+    public int expected { get; }
+
+    public AssertPcCommand(CompareOp op, int expected)
+    {
+        this.op = op;
+        this.expected = expected;
+    }
+
+    public override void execute(ScriptRunner runner) =>
+        runner.checkCompare(this, "PC", runner.machine.pc, op, expected);
+
+    public override string describe() => "assert pc " + CompareOps.symbol(op) + " " + expected;
+}
+
+public sealed class AssertPixelCommand : ScriptCommand
+{
+    public int x { get; }
+    public int y { get; }
+    public bool expectedLit { get; }
+
+    public AssertPixelCommand(int x, int y, bool expectedLit)
+    {
+        this.x = x;
+        this.y = y;
+        this.expectedLit = expectedLit;
+    }
+
+    public override void execute(ScriptRunner runner) => runner.checkPixel(this);
+
+    public override string describe() =>
+        "assert pixel " + x + " " + y + " " + (expectedLit ? "on" : "off");
+}
+
+public sealed class AssertExitedCommand : ScriptCommand
+{
+    public bool expectedExited { get; }
+
+    public AssertExitedCommand(bool expectedExited)
+    {
+        this.expectedExited = expectedExited;
+    }
+
+    public override void execute(ScriptRunner runner) => runner.checkExited(this);
+
+    public override string describe() => expectedExited ? "assert exited" : "assert running";
+}
+
+public static class CompareOps
+{
+    public static string symbol(CompareOp op) => op == CompareOp.Equal ? "==" : "!=";
+
+    public static bool evaluate(CompareOp op, int left, int right) =>
+        op == CompareOp.Equal ? left == right : left != right;
+}