using System.Numerics;
using AcDream.App.Streaming;
using AcDream.App.World;
using AcDream.Core.Net;
using AcDream.Core.Net.Messages;
using AcDream.Core.Physics;
using AcDream.Core.World;
using DatReaderWriter.DBObjs;

namespace AcDream.App.Tests.World;

public sealed class LiveEntityPresentationControllerTests
{
    [Fact]
    public void InitialVisibleObject_DoesNotPlayUnHide()
    {
        Fixture fixture = new(PhysicsStateFlags.ReportCollisions);

        Assert.True(fixture.Controller.OnLiveEntityReady(Fixture.Guid));

        Assert.Empty(fixture.TypedPlays);
        Assert.True(fixture.Entity.IsDrawVisible);
        Assert.Equal(1, fixture.Shadows.TotalRegistered);
    }

    [Fact]
    public void HiddenThenVisible_PlaysTypedEffectsMutatesChildrenAndRestoresShadow()
    {
        Fixture fixture = new(
            PhysicsStateFlags.Hidden | PhysicsStateFlags.ReportCollisions);

        Assert.True(fixture.Controller.OnLiveEntityReady(Fixture.Guid));

        Assert.Equal(
            [(fixture.Entity.Id, LiveEntityPresentationController.HiddenScriptType, 1f)],
            fixture.TypedPlays);
        Assert.Equal([(Fixture.Guid, true)], fixture.ChildNoDraw);
        Assert.Equal([Fixture.Guid], fixture.InvalidTargets);
        Assert.Equal(0, fixture.Shadows.TotalRegistered);
        Assert.False(fixture.Entity.IsDrawVisible);

        Assert.True(fixture.Runtime.TryApplyState(
            new SetState.Parsed(Fixture.Guid, 0u, 1, 2),
            out _,
            out _));
        Assert.True(fixture.Controller.OnStateAccepted(Fixture.Guid));

        Assert.Equal(
            [
                (fixture.Entity.Id, LiveEntityPresentationController.HiddenScriptType, 1f),
                (fixture.Entity.Id, LiveEntityPresentationController.UnHideScriptType, 1f),
            ],
            fixture.TypedPlays);
        Assert.Equal([(Fixture.Guid, true), (Fixture.Guid, false)], fixture.ChildNoDraw);
        Assert.Equal(1, fixture.Shadows.TotalRegistered);
        Assert.True(fixture.Entity.IsDrawVisible);
        Assert.Same(fixture.Entity, Assert.Single(fixture.Runtime.WorldEntities).Value);
    }

    [Fact]
    public void IdenticalOrStaleState_DoesNotReplayHiddenEffect()
    {
        Fixture fixture = new(PhysicsStateFlags.ReportCollisions);
        fixture.Controller.OnLiveEntityReady(Fixture.Guid);
        var hidden = new SetState.Parsed(
            Fixture.Guid,
            (uint)(PhysicsStateFlags.Hidden | PhysicsStateFlags.ReportCollisions),
            1,
            2);

        Assert.True(fixture.Runtime.TryApplyState(hidden, out _, out _));
        fixture.Controller.OnStateAccepted(Fixture.Guid);
        Assert.False(fixture.Runtime.TryApplyState(hidden, out _, out _));
        fixture.Controller.OnStateAccepted(Fixture.Guid);

        Assert.Single(fixture.TypedPlays);
        Assert.Equal(LiveEntityPresentationController.HiddenScriptType,
            fixture.TypedPlays[0].Type);
    }

    [Fact]
    public void UnHideWhileLandblockPending_RestoresShadowWhenProjectionReturns()
    {
        Fixture fixture = new(PhysicsStateFlags.ReportCollisions);
        fixture.Controller.OnLiveEntityReady(Fixture.Guid);

        Assert.True(fixture.Runtime.TryApplyState(
            new SetState.Parsed(
                Fixture.Guid,
                (uint)(PhysicsStateFlags.Hidden | PhysicsStateFlags.ReportCollisions),
                1,
                2),
            out _,
            out _));
        fixture.Controller.OnStateAccepted(Fixture.Guid);
        Assert.Equal(0, fixture.Shadows.TotalRegistered);

        Assert.True(fixture.Runtime.RebucketLiveEntity(Fixture.Guid, 0x02020001u));
        Assert.False(fixture.Runtime.WorldEntities.ContainsKey(Fixture.Guid));

        Assert.True(fixture.Runtime.TryApplyState(
            new SetState.Parsed(Fixture.Guid, 0u, 1, 3),
            out _,
            out _));
        fixture.Controller.OnStateAccepted(Fixture.Guid);
        Assert.Equal(0, fixture.Shadows.TotalRegistered);

        fixture.Spatial.AddLandblock(new LoadedLandblock(
            0x0202FFFFu,
            new LandBlock(),
            Array.Empty<WorldEntity>()));

        Assert.True(fixture.Runtime.WorldEntities.ContainsKey(Fixture.Guid));
        Assert.Equal(1, fixture.Shadows.TotalRegistered);
    }

    [Fact]
    public void ActivePlacement_IsGenerationScopedAndClearsOnTeardownAndReset()
    {
        Fixture fixture = new(PhysicsStateFlags.ReportCollisions);
        Assert.True(fixture.Controller.OnLiveEntityReady(Fixture.Guid));
        Assert.True(fixture.Controller.BeginAuthoritativePlacement(Fixture.Guid, 1));
        Assert.True(fixture.Controller.HasActivePlacement(Fixture.Guid));
        Assert.True(fixture.Runtime.TryGetRecord(Fixture.Guid, out LiveEntityRecord oldRecord));

        fixture.Controller.Forget(oldRecord);
        Assert.True(fixture.Runtime.UnregisterLiveEntity(
            new DeleteObject.Parsed(Fixture.Guid, 1),
            isLocalPlayer: false));
        Assert.False(fixture.Controller.HasActivePlacement(Fixture.Guid));

        fixture.Runtime.RegisterLiveEntity(Fixture.Spawn(
            PhysicsStateFlags.ReportCollisions,
            instanceSequence: 2));
        fixture.Runtime.MaterializeLiveEntity(
            Fixture.Guid,
            0x01010001u,
            id => new WorldEntity
            {
                Id = id,
                ServerGuid = Fixture.Guid,
                SourceGfxObjOrSetupId = 0x02000001u,
                Position = new Vector3(10f, 10f, 5f),
                Rotation = Quaternion.Identity,
                MeshRefs = Array.Empty<MeshRef>(),
            });
        Assert.True(fixture.Controller.OnLiveEntityReady(Fixture.Guid));

        Assert.False(fixture.Controller.CompleteAuthoritativePlacement(
            Fixture.Guid,
            generation: 1,
            deferShadowRestore: true));
        Assert.False(fixture.Controller.HasDeferredShadowRestore(Fixture.Guid));
        Assert.True(fixture.Controller.BeginAuthoritativePlacement(Fixture.Guid, 2));
        Assert.True(fixture.Controller.HasActivePlacement(Fixture.Guid));

        fixture.Controller.Clear();

        Assert.False(fixture.Controller.HasActivePlacement(Fixture.Guid));
        Assert.False(fixture.Controller.HasDeferredShadowRestore(Fixture.Guid));
    }

    private sealed class Fixture
    {
        public const uint Guid = 0x70000051u;
        public List<(uint Owner, uint Type, float Intensity)> TypedPlays { get; } = [];
        public List<(uint Parent, bool NoDraw)> ChildNoDraw { get; } = [];
        public List<uint> InvalidTargets { get; } = [];
        public GpuWorldState Spatial { get; }
        public LiveEntityRuntime Runtime { get; }
        public ShadowObjectRegistry Shadows { get; } = new();
        public WorldEntity Entity { get; }
        public LiveEntityPresentationController Controller { get; }

        public Fixture(PhysicsStateFlags initialState)
        {
            Spatial = new GpuWorldState();
            Spatial.AddLandblock(new LoadedLandblock(
                0x0101FFFFu,
                new LandBlock(),
                Array.Empty<WorldEntity>()));
            Runtime = new LiveEntityRuntime(
                Spatial,
                new DelegateLiveEntityResourceLifecycle(_ => { }, _ => { }));
            WorldSession.EntitySpawn spawn = Spawn(initialState);
            Runtime.RegisterLiveEntity(spawn);
            Entity = Runtime.MaterializeLiveEntity(
                Guid,
                0x01010001u,
                id => new WorldEntity
                {
                    Id = id,
                    ServerGuid = Guid,
                    SourceGfxObjOrSetupId = 0x02000001u,
                    Position = new Vector3(10f, 10f, 5f),
                    Rotation = Quaternion.Identity,
                    MeshRefs = Array.Empty<MeshRef>(),
                })!;
            Shadows.Register(
                Entity.Id,
                0x01000001u,
                Entity.Position,
                Entity.Rotation,
                1f,
                0f,
                0f,
                0x01010000u,
                state: (uint)initialState,
                seedCellId: 0x01010001u);

            Controller = new LiveEntityPresentationController(
                Runtime,
                Shadows,
                (owner, type, intensity) =>
                {
                    TypedPlays.Add((owner, type, intensity));
                    return true;
                },
                (parent, noDraw) => ChildNoDraw.Add((parent, noDraw)),
                InvalidTargets.Add,
                () => (1, 1));
        }

        internal static WorldSession.EntitySpawn Spawn(
            PhysicsStateFlags state,
            ushort instanceSequence = 1)
        {
            var position = new CreateObject.ServerPosition(
                0x01010001u, 10f, 10f, 5f, 1f, 0f, 0f, 0f);
            var timestamps = new PhysicsTimestamps(1, 1, 1, 1, 0, 1, 0, 1, 1);
            var physics = new PhysicsSpawnData(
                RawState: (uint)state,
                Position: position,
                Movement: null,
                AnimationFrame: null,
                SetupTableId: 0x02000001u,
                MotionTableId: 0x09000001u,
                SoundTableId: null,
                PhysicsScriptTableId: null,
                Parent: null,
                Children: null,
                Scale: null,
                Friction: null,
                Elasticity: null,
                Translucency: null,
                Velocity: null,
                Acceleration: null,
                AngularVelocity: null,
                DefaultScriptType: null,
                DefaultScriptIntensity: null,
                Timestamps: timestamps);
            return new WorldSession.EntitySpawn(
                Guid,
                position,
                0x02000001u,
                Array.Empty<CreateObject.AnimPartChange>(),
                Array.Empty<CreateObject.TextureChange>(),
                Array.Empty<CreateObject.SubPaletteSwap>(),
                null,
                null,
                "fixture",
                null,
                null,
                MotionTableId: 0x09000001u,
                PhysicsState: (uint)state,
                InstanceSequence: instanceSequence,
                MovementSequence: 1,
                ServerControlSequence: 1,
                PositionSequence: 1,
                Physics: physics);
        }
    }
}