using System;
using System.Runtime.InteropServices;
using UnityEngine;

public static class QExtensions
{
    public static TStruct[] ToStructArray<TStruct>(this IntPtr ptr, int count)
    {
        if (ptr == IntPtr.Zero)
            return null;
        
        TStruct[] result = new TStruct[count];
        int size = Marshal.SizeOf<TStruct>();
        IntPtr current = ptr;
        for (int i = 0; i < count; ++i)
        {
            result[i] = Marshal.PtrToStructure<TStruct>(current);
            current = IntPtr.Add(current, size);
        }
        return result;
    }

    public static int[] ToIntArray(this IntPtr ptr, int count)
    {
        if (ptr == IntPtr.Zero)
            return null;

        int[] result = new int[count];
        Marshal.Copy(ptr, result, 0, count);
        return result;
    }

    public static Vector2 ToVector2(this QVec2 vec)
    {
        return new Vector2(vec.x, vec.y);
    }
    
    public static Vector3 ToVector3(this QVec3 vec)
    {
        return new Vector3(vec.x, vec.y, vec.z);
    }

    public static Vector3 ToVector3(this QTriVertex triVertex)
    {
        byte[] v = triVertex.v;
        return new Vector3(v[0], v[1], v[2]);
    }

    public static Vector3 ToUnity(this Vector3 vec)
    {
        return new Vector3(vec.y, vec.z, -vec.x);
    }

    public static Vector3 ToUnityPosition(this QVec3 origin)
    {
        return new Vector3(origin.y, origin.z, -origin.x);
    }
    
    public static Vector3 ToUnityDirection(this QVec3 dir)
    {
        return new Vector3(dir.y, dir.z, -dir.x);
    }

    public static Quaternion ToUnityRotation(this QVec3 angles)
    {
        return Quaternion.AngleAxis(-angles.y, Vector3.up)
               * Quaternion.AngleAxis(angles.x, Vector3.right)
               * Quaternion.AngleAxis(angles.z, Vector3.forward);
    }

    public static Color ToColor(this uint color)
    {
        return new Color32(
            (byte)(color & 0xFF),
            (byte)((color >> 8) & 0xFF),
            (byte)((color >> 16) & 0xFF),
            (byte)((color >> 24) & 0xFF));
    }

    public static Color ToColor(this QVec3 vec)
    {
        return new Color(vec.x, vec.y, vec.z);
    }
}