using AcDream.Core.Net;
using AcDream.Core.Net.Messages;
using AcDream.Core.Physics;
using AcDream.Runtime.Entities;

namespace AcDream.Runtime.Tests.Entities;

public sealed class RuntimeEntityObjectLifetimeTests
{
    [Fact]
    public void Owner_ConstructsOneExactDirectoryAndObjectTablePerInstance()
    {
        var first = new RuntimeEntityObjectLifetime();
        var second = new RuntimeEntityObjectLifetime();

        Assert.NotSame(first.Entities, second.Entities);
        Assert.NotSame(first.Objects, second.Objects);
        Assert.Same(first.Entities, first.Entities);
        Assert.Same(first.Objects, first.Objects);
    }

    [Fact]
    public void Owner_ConstructionLoadsNoPresentationOrBackendAssembly()
    {
        _ = new RuntimeEntityObjectLifetime();

        string[] loaded = AppDomain.CurrentDomain
            .GetAssemblies()
            .Select(assembly => assembly.GetName().Name ?? string.Empty)
            .ToArray();
        Assert.DoesNotContain(loaded, name =>
            name.StartsWith("AcDream.App", StringComparison.Ordinal)
            || name.StartsWith("AcDream.UI.", StringComparison.Ordinal)
            || name.StartsWith("Silk.NET", StringComparison.Ordinal)
            || name.StartsWith("OpenAL", StringComparison.Ordinal)
            || name.StartsWith("ImGui", StringComparison.Ordinal));
    }

    [Fact]
    public void SeparateOwners_IsolateConflictingGuidsAndContents()
    {
        const uint guid = 0x70000001u;
        var first = new RuntimeEntityObjectLifetime();
        var second = new RuntimeEntityObjectLifetime();
        RuntimeEntityRecord firstRecord = Accept(first, Spawn(guid, 1, "first"));
        RuntimeEntityRecord secondRecord = Accept(second, Spawn(guid, 9, "second"));

        Assert.True(first.ApplyAcceptedSpawn(
            firstRecord,
            firstRecord.CreateIntegrationVersion,
            firstRecord.Snapshot,
            replaceGeneration: false));
        Assert.True(second.ApplyAcceptedSpawn(
            secondRecord,
            secondRecord.CreateIntegrationVersion,
            secondRecord.Snapshot,
            replaceGeneration: false));

        Assert.Equal("first", first.Objects.Get(guid)!.Name);
        Assert.Equal("second", second.Objects.Get(guid)!.Name);
        Assert.Equal((ushort)1, firstRecord.Incarnation);
        Assert.Equal((ushort)9, secondRecord.Incarnation);
    }

    [Fact]
    public void AcceptedSpawn_RejectsWrongOrSupersededCanonicalIncarnation()
    {
        var lifetime = new RuntimeEntityObjectLifetime();
        WorldSession.EntitySpawn spawn = Spawn(0x70000002u, 3, "current");
        RuntimeEntityRecord canonical = Accept(lifetime, spawn);
        var wrong = new RuntimeEntityObjectLifetime();
        RuntimeEntityRecord wrongCanonical = Accept(wrong, spawn);

        Assert.False(lifetime.ApplyAcceptedSpawn(
            wrongCanonical,
            wrongCanonical.CreateIntegrationVersion,
            spawn,
            replaceGeneration: false));

        ulong expectedVersion = canonical.CreateIntegrationVersion;
        lifetime.Entities.AdvanceCreateAuthority(canonical);
        Assert.False(lifetime.ApplyAcceptedSpawn(
            canonical,
            expectedVersion,
            spawn,
            replaceGeneration: false));
        Assert.Null(lifetime.Objects.Get(spawn.Guid));
    }

    [Fact]
    public void AcceptedSpawn_RevalidatesAfterSynchronousObjectCallbacks()
    {
        var lifetime = new RuntimeEntityObjectLifetime();
        WorldSession.EntitySpawn spawn = Spawn(0x70000003u, 4, "reentrant");
        RuntimeEntityRecord canonical = Accept(lifetime, spawn);
        ulong expectedVersion = canonical.CreateIntegrationVersion;
        lifetime.Objects.ObjectAdded += _ =>
            lifetime.Entities.AdvanceCreateAuthority(canonical);

        Assert.False(lifetime.ApplyAcceptedSpawn(
            canonical,
            expectedVersion,
            spawn,
            replaceGeneration: false));
        Assert.NotNull(lifetime.Objects.Get(spawn.Guid));
    }

    [Fact]
    public void AcceptedDelete_RemovesOnlyMatchingLogicalGeneration()
    {
        var lifetime = new RuntimeEntityObjectLifetime();
        WorldSession.EntitySpawn spawn = Spawn(0x70000004u, 6, "retained");
        RuntimeEntityRecord canonical = Accept(lifetime, spawn);
        Assert.True(lifetime.ApplyAcceptedSpawn(
            canonical,
            canonical.CreateIntegrationVersion,
            spawn,
            replaceGeneration: true));

        Assert.False(lifetime.TryAcceptDelete(
            new DeleteObject.Parsed(spawn.Guid, 7),
            isLocalPlayer: false,
            out _));
        Assert.NotNull(lifetime.Objects.Get(spawn.Guid));

        Assert.True(lifetime.TryAcceptDelete(
            new DeleteObject.Parsed(spawn.Guid, 6),
            isLocalPlayer: false,
            out RuntimeEntityDeleteAcceptance accepted));
        lifetime.CompleteAcceptedDelete(accepted);
        Assert.Null(lifetime.Objects.Get(spawn.Guid));
    }

    [Fact]
    public void DeleteAcceptance_CannotCrossOwnersOrReplay()
    {
        var owner = new RuntimeEntityObjectLifetime();
        var other = new RuntimeEntityObjectLifetime();
        WorldSession.EntitySpawn spawn = Spawn(0x70000006u, 8, "token");
        RuntimeEntityRecord canonical = Accept(owner, spawn);
        Assert.True(owner.ApplyAcceptedSpawn(
            canonical,
            canonical.CreateIntegrationVersion,
            spawn,
            replaceGeneration: true));
        Assert.True(owner.TryAcceptDelete(
            new DeleteObject.Parsed(spawn.Guid, spawn.InstanceSequence),
            isLocalPlayer: false,
            out RuntimeEntityDeleteAcceptance acceptance));

        Assert.Throws<InvalidOperationException>(
            () => other.CompleteAcceptedDelete(acceptance));
        owner.CompleteAcceptedDelete(acceptance);
        Assert.Throws<InvalidOperationException>(
            () => owner.CompleteAcceptedDelete(acceptance));
        Assert.Null(owner.Objects.Get(spawn.Guid));
    }

    [Fact]
    public void ClearObjects_DoesNotResetCanonicalEntityIdentity()
    {
        var lifetime = new RuntimeEntityObjectLifetime();
        WorldSession.EntitySpawn spawn = Spawn(0x70000005u, 2, "clear");
        RuntimeEntityRecord canonical = Accept(lifetime, spawn);
        Assert.True(lifetime.ApplyAcceptedSpawn(
            canonical,
            canonical.CreateIntegrationVersion,
            spawn,
            replaceGeneration: false));

        lifetime.ClearObjects();

        Assert.Null(lifetime.Objects.Get(spawn.Guid));
        Assert.True(lifetime.Entities.TryGetActive(spawn.Guid, out var retained));
        Assert.Same(canonical, retained);
    }

    private static RuntimeEntityRecord Accept(
        RuntimeEntityObjectLifetime lifetime,
        WorldSession.EntitySpawn spawn)
    {
        InboundCreateResult accepted = lifetime.Entities.AcceptCreate(spawn);
        return lifetime.Entities.AddActive(accepted.Snapshot);
    }

    private static WorldSession.EntitySpawn Spawn(
        uint guid,
        ushort instance,
        string name)
    {
        var position = new CreateObject.ServerPosition(
            0x0101FFFFu,
            10f,
            20f,
            5f,
            1f,
            0f,
            0f,
            0f);
        var timestamps = new PhysicsTimestamps(
            Position: 1,
            Movement: 1,
            State: 1,
            Vector: 1,
            Teleport: 0,
            ServerControlledMove: 1,
            ForcePosition: 0,
            ObjDesc: 1,
            Instance: instance);
        var physics = new PhysicsSpawnData(
            RawState: 0x408u,
            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,
            name,
            null,
            null,
            0x09000001u,
            PhysicsState: 0x408u,
            InstanceSequence: instance,
            MovementSequence: 1,
            ServerControlSequence: 1,
            PositionSequence: 1,
            Physics: physics);
    }
}