namespace Glamourer.GameData;

public readonly struct CustomizeParameterValue
{
    public static readonly CustomizeParameterValue Zero = default;

    private readonly Vector4 _data;

    public CustomizeParameterValue(Vector4 data)
        => _data = data;

    public CustomizeParameterValue(Vector3 data, float w = 0)
        => _data = new Vector4(data, w);

    public CustomizeParameterValue(FFXIVClientStructs.FFXIV.Common.Math.Vector4 data)
        => _data = new Vector4(Root(data.X), Root(data.Y), Root(data.Z), data.W);

    public CustomizeParameterValue(FFXIVClientStructs.FFXIV.Common.Math.Vector3 data)
        => _data = new Vector4(Root(data.X), Root(data.Y), Root(data.Z), 0);

    public CustomizeParameterValue(float value, float y = 0, float z = 0, float w = 0)
        => _data = new Vector4(value, y, z, w);

    public Vector3 InternalTriple
        => new(_data.X, _data.Y, _data.Z);

    public float Single
        => _data.X;

    public Vector4 InternalQuadruple
        => _data;

    public FFXIVClientStructs.FFXIV.Common.Math.Vector4 XivQuadruple
        => new(Square(_data.X), Square(_data.Y), Square(_data.Z), _data.W);

    public FFXIVClientStructs.FFXIV.Common.Math.Vector3 XivTriple
        => new(Square(_data.X), Square(_data.Y), Square(_data.Z));

    private static float Square(float x)
        => x < 0 ? -x * x : x * x;

    private static float Root(float x)
        => x < 0 ? -(float)Math.Sqrt(-x) : (float)Math.Sqrt(x);

    public float this[int idx]
        => _data[idx];

    public override string ToString()
        => _data.ToString();
}

public static class VectorExtensions
{
    [MethodImpl(MethodImplOptions.AggressiveOptimization | MethodImplOptions.AggressiveInlining)]
    public static bool NearEqual(this Vector3 lhs, Vector3 rhs, float eps = 1e-9f)
        => (lhs - rhs).LengthSquared() < eps;

    [MethodImpl(MethodImplOptions.AggressiveOptimization | MethodImplOptions.AggressiveInlining)]
    public static bool NearEqual(this Vector4 lhs, Vector4 rhs, float eps = 1e-9f)
        => (lhs - rhs).LengthSquared() < eps;

    [MethodImpl(MethodImplOptions.AggressiveOptimization | MethodImplOptions.AggressiveInlining)]
    public static bool NearEqual(this CustomizeParameterValue lhs, CustomizeParameterValue rhs, float eps = 1e-9f)
        => NearEqual(lhs.InternalQuadruple, rhs.InternalQuadruple, eps);

    [MethodImpl(MethodImplOptions.AggressiveOptimization | MethodImplOptions.AggressiveInlining)]
    public static bool NearEqual(this float lhs, float rhs, float eps = 1e-5f)
    {
        var diff = lhs - rhs;
        return diff < 0 ? diff > -eps : diff < eps;
    }
}