using System.Numerics;
using AcDream.Core.World;
using Xunit;

namespace AcDream.Core.Tests.World;

public class WorldEntityAabbTests
{
    [Fact]
    public void Aabb_DefaultRadius_PositionPlusMinus5()
    {
        var entity = new WorldEntity
        {
            Id = 1,
            SourceGfxObjOrSetupId = 0,
            Position = new Vector3(10, 20, 30),
            Rotation = System.Numerics.Quaternion.Identity,
            MeshRefs = System.Array.Empty<MeshRef>(),
        };
        entity.RefreshAabb();

        Assert.Equal(new Vector3(5, 15, 25), entity.AabbMin);
        Assert.Equal(new Vector3(15, 25, 35), entity.AabbMax);
    }

    [Fact]
    public void Aabb_MultiPartOffsets_CoverTheParts()
    {
        // #119 follow-up: the AAB3 tower staircase — 43 parts spiralling to
        // (3, 3, 15.15) root-relative. The box (and the viewcone sphere derived
        // from it) must cover the parts, not just the ±5 m anchor neighborhood;
        // the anchor-only box made the staircase vanish whenever the gaze left
        // the base (visible climbing down, gone climbing up).
        var entity = new WorldEntity
        {
            Id = 1,
            SourceGfxObjOrSetupId = 0x020003F2,
            Position = new Vector3(300, -132, 112),
            Rotation = System.Numerics.Quaternion.Identity,
            MeshRefs = new[]
            {
                new MeshRef(0x01000E2A, Matrix4x4.CreateTranslation(0f, 3f, 1.55f)),
                new MeshRef(0x01000E2D, Matrix4x4.CreateTranslation(-1.75f, 3f, 15.15f)),
            },
        };
        entity.RefreshAabb();

        // Top part sits at z = 112 + 15.15 = 127.15 — must be inside the box.
        Assert.True(entity.AabbMax.Z >= 127.15f,
            $"box top {entity.AabbMax.Z} must cover the highest part (z=127.15)");
        // Conservative symmetric expansion still contains the old ±5 box.
        Assert.True(entity.AabbMin.Z <= 107f && entity.AabbMax.X >= 305f);
    }

    [Fact]
    public void Aabb_DirtyFlag_SetByMutator_ClearedByRefresh()
    {
        var entity = new WorldEntity
        {
            Id = 1,
            SourceGfxObjOrSetupId = 0,
            Position = new Vector3(10, 20, 30),
            Rotation = System.Numerics.Quaternion.Identity,
            MeshRefs = System.Array.Empty<MeshRef>(),
        };
        entity.RefreshAabb();
        Assert.False(entity.AabbDirty);

        entity.SetPosition(new Vector3(100, 200, 300));
        Assert.True(entity.AabbDirty);

        entity.RefreshAabb();
        Assert.False(entity.AabbDirty);
        Assert.Equal(new Vector3(95, 195, 295), entity.AabbMin);
    }
}