using System.Numerics;
using Aquarium.LocalCast;

namespace Aquarium.LocalCast.Tests;

public sealed class LocalCastNativeVisualFrameSourceTests
{
    [Fact]
    public void ReadsLatestRenderPacketFromNativeRuntimeThroughInjectedDecoder()
    {
        var sample = new LocalCastNativeSampleHandle
        {
            SensorIdHash = 11,
            TimestampNs = 1_000,
            ArrivalNs = 1_010,
            Sequence = 7,
            PayloadHandle = 99,
            Flags = LocalCastNativeSampleFlags.None,
        };
        var runtime = new FakeNativeRuntime(sample, renderPacketCount: 2);
        var source = new LocalCastNativeVisualFrameSource(
            runtime,
            (LocalCastNativeSampleHandle handle, out LocalCastVisualFrame frame) =>
            {
                frame = FrameFromPayload(handle.PayloadHandle, handle.TimestampNs);
                return true;
            });

        Assert.True(source.TryReadLatest(out var frame));
        Assert.Equal(99, frame.FrameId);
        Assert.Equal(1_000, frame.SourceTimeMaxNs);
        Assert.Equal(1, runtime.ViewReadCount);
    }

    [Fact]
    public void RejectsMissingOrNonLiveRenderPacket()
    {
        var diagnostic = new LocalCastNativeSampleHandle
        {
            SensorIdHash = 11,
            TimestampNs = 1_000,
            ArrivalNs = 1_010,
            Sequence = 7,
            PayloadHandle = 99,
            Flags = LocalCastNativeSampleFlags.Diagnostic,
        };
        var source = new LocalCastNativeVisualFrameSource(
            new FakeNativeRuntime(diagnostic, renderPacketCount: 1),
            (LocalCastNativeSampleHandle _, out LocalCastVisualFrame frame) =>
            {
                frame = FrameFromPayload(1, 1);
                return true;
            });

        Assert.False(source.TryReadLatest(out _));

        var empty = new LocalCastNativeVisualFrameSource(
            new FakeNativeRuntime(diagnostic, renderPacketCount: 0),
            (LocalCastNativeSampleHandle _, out LocalCastVisualFrame frame) =>
            {
                frame = FrameFromPayload(1, 1);
                return true;
            });
        Assert.False(empty.TryReadLatest(out _));
    }

    private static LocalCastVisualFrame FrameFromPayload(ulong payloadHandle, ulong timestampNs)
    {
        return new LocalCastVisualFrame
        {
            SchemaVersion = LocalCastVisualStateReader.RenderFrameSchemaId,
            FrameId = (long)payloadHandle,
            CreatedMonotonicNs = (long)timestampNs,
            SourceTimeMinNs = (long)timestampNs,
            SourceTimeMaxNs = (long)timestampNs,
            PresentTimeNs = (long)timestampNs,
            AudioAlignmentTimeNs = (long)timestampNs,
            SpoutSenderName = "LocalCastBridge Point Cloud",
            TargetWidth = 1920,
            TargetHeight = 1080,
            Points =
            [
                new LocalCastVisualPoint(
                    "native:point",
                    new Vector3(0.1f, 0.2f, 1.2f),
                    0.03f,
                    new Vector4(0.7f, 0.6f, 0.5f, 0.9f),
                    0.8f,
                    (long)timestampNs),
            ],
        };
    }

    private sealed class FakeNativeRuntime : ILocalCastNativeRuntime
    {
        private readonly LocalCastNativeSampleHandle sample;
        private readonly UIntPtr renderPacketCount;

        public FakeNativeRuntime(LocalCastNativeSampleHandle sample, int renderPacketCount)
        {
            this.sample = sample;
            this.renderPacketCount = (UIntPtr)renderPacketCount;
        }

        public int ViewReadCount { get; private set; }

        public bool TryGetStatus(out LocalCastNativeRuntimeStatus status)
        {
            status = new LocalCastNativeRuntimeStatus
            {
                TotalSampleCount = renderPacketCount,
                RenderPacketCount = renderPacketCount,
            };
            return true;
        }

        public bool TryReadSample(nuint index, out LocalCastNativeSampleKind kind, out LocalCastNativeSampleHandle sample)
        {
            kind = LocalCastNativeSampleKind.RenderPacket;
            sample = this.sample;
            return true;
        }

        public bool TryReadViewSample(LocalCastNativeSampleKind kind, nuint index, out LocalCastNativeSampleHandle sample)
        {
            ViewReadCount++;
            sample = this.sample;
            return kind == LocalCastNativeSampleKind.RenderPacket && index + 1 == renderPacketCount;
        }

        public bool TryReadLatestForSensor(LocalCastNativeSampleKind kind, ulong sensorIdHash, out LocalCastNativeSampleHandle sample)
        {
            sample = this.sample;
            return true;
        }

        public void Dispose()
        {
        }
    }
}