Implement SC0000 movie playback lifecycle

engine/Age.Engine.Tests/MovieOpcodeTests.cs

@@ -0,0 +1,101 @@
+using System.Collections.Generic;
+using Age.Engine.Diagnostics;
+using Age.Engine.Hosting;
+using Age.Engine.Model;
+using Age.Engine.Sys4;
+using Age.Engine.Vm;
+using Xunit;
+
+public class MovieOpcodeTests
+{
+    [Fact]
+    public void Sc0000ResumesImmediatelyAfterMovieOpcodeAtBytecodeOffset13d1()
+    {
+        var table = OpcodeTableJson.Load(Paths.OpcodesJson);
+        var provider = Sys4ScriptProvider.Load(table);
+        var session = new GameSession();
+        foreach (var name in new[] { "INITCONFIG.BIN", "INIT2.BIN", "INIT.BIN" })
+            session.RunScene(Sys4Loader.Load(Paths.Scripts()[name], table), table, new CaptureHost(), provider: provider);
+        var script = Sys4Loader.Load(Paths.Scripts()["SC0000.BIN"], table);
+        var host = new RecordingHost();
+        var trace = new RecordingTraceSink { TracingSteps = true };
+        var vm = new VirtualMachine(script, table, host, new VmOptions(MaxSteps: 20_000_000), provider, trace);
+        foreach (var kv in session.Globals) vm.Globals[kv.Key] = kv.Value;
+        foreach (var kv in session.GlobalStrings) vm.GlobalStrings[kv.Key] = kv.Value;
+
+        vm.Run();
+
+        int movieStep = trace.Events.FindIndex(e => e.Kind == TraceEventKind.Step && e.Opcode == 0x236);
+        Assert.True(movieStep >= 0);
+        var nextStep = trace.Events.Skip(movieStep + 1).First(e => e.Kind == TraceEventKind.Step);
+        Assert.Equal(0x13c8, trace.Events[movieStep].Ins!.Offset);
+        Assert.Equal(0x13d1, nextStep.Ins!.Offset);
+        Assert.Contains((0x33L, 0, 2L, 0L), host.Movies);
+    }
+
+    [Fact]
+    public void PlayMovieDispatchesExactOperandsAndResumesAtNextInstruction()
+    {
+        var table = OpcodeTableJson.Load(Paths.OpcodesJson);
+        var script = ScriptAssembler.Assemble(table, "MOVIE", new List<(int, Operand[])>
+        {
+            (0x236, new[] { new Operand(0, 0x33), new Operand(0, 5), new Operand(0, 2), new Operand(0, 0) }),
+            (0x55, new[] { new Operand(3, 0x1234), new Operand(0, 0x5678) }),
+            (0x2, System.Array.Empty<Operand>()),
+        }, System.Array.Empty<string>());
+        var host = new RecordingHost();
+        var vm = new VirtualMachine(script, table, host);
+
+        vm.Run();
+
+        Assert.Equal("exit", vm.HaltReason);
+        Assert.Equal(0x5678, vm.Globals[0x1234]);
+        Assert.Equal(new[] { (0x33L, 5, 2L, 0L) }, host.Movies);
+        vm.Gfx.BindDraw(1, 5, 0, 0, 1, 1, 0, 0);
+        Assert.Equal(0x33, vm.Gfx.SnapshotVisibleObjects().Single().SurfaceResId);
+    }
+
+    [Fact]
+    public void Sc0000MoviePayloadReadsFromArchiveVfsAndIsMpegProgramStream()
+    {
+        var catalog = Sys4AssetCatalog.Load(Paths.Sys4Ini);
+        var resources = new ResourceMap(catalog, new Sys4AssetStore(catalog, Paths.GameDir));
+        var entry = resources.Resolve("SC0000", 0x33);
+
+        Assert.Equal("CHAPTER.AGF", entry?.Name);
+        var movie = resources.ReadMovie(entry!);
+        Assert.Equal(new byte[] { 0, 0, 1, 0xba }, movie.Bytes[..4]);
+        Assert.Equal(8_194_052, movie.Bytes.Length);
+    }
+
+    [Fact]
+    public void Sc0000MoviePayloadDecodesAn800By600FrameOnWindows()
+    {
+        if (!OperatingSystem.IsWindows()) return;
+        var catalog = Sys4AssetCatalog.Load(Paths.Sys4Ini);
+        var resources = new ResourceMap(catalog, new Sys4AssetStore(catalog, Paths.GameDir));
+        var entry = resources.Resolve("SC0000", 0x33)!;
+        using var decoder = new DirectShowMovieDecoder(resources.ReadMovie(entry));
+
+        var deadline = DateTime.UtcNow.AddSeconds(10);
+        RgbaImage? frame = null;
+        while (DateTime.UtcNow < deadline && !decoder.TryTakeFrame(out frame))
+            Thread.Sleep(20);
+
+        Assert.NotNull(frame);
+        Assert.Equal(800, frame!.Width);
+        Assert.Equal(600, frame.Height);
+        Assert.Equal(800 * 600 * 4, frame.Pixels.Length);
+
+        byte[] firstPixels = frame.Pixels;
+        var changeDeadline = DateTime.UtcNow.AddSeconds(2);
+        bool changed = false;
+        while (DateTime.UtcNow < changeDeadline && !changed)
+        {
+            Thread.Sleep(20);
+            if (decoder.TryTakeFrame(out var later))
+                changed = !firstPixels.AsSpan().SequenceEqual(later.Pixels);
+        }
+        Assert.True(changed, "DirectShow should deliver changing MPEG frames, not one retained still");
+    }
+}