using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System.Text;

namespace StgSharp.Math
{
    [StructLayout(LayoutKind.Explicit)]
    public struct Array3x2:IEquatable<Array3x2>
    {
        [FieldOffset(0)]
        public Vec2D row1;
        [FieldOffset(8)]
        public Vec2D row2;
        [FieldOffset(16)]
        public Vec2D row3;

        public Array3x2(Vec2D r1,Vec2D r2,Vec2D r3)
        {
            row1= r1;
            row2= r2;
            row3= r3;
        }
        bool IEquatable<Array3x2>.Equals(Array3x2 other)
        {
            if (this.GetHashCode() != other.GetHashCode())
            {
                return false;
            }
            else
            {
                return
                    this.row1 == other.row1
                    && this.row2 == other.row2
                    && this.row3 == other.row3
                    ;
            }
        }

        public override bool Equals(object obj)
        {
            if (obj == null)
            {
                return false;
            }
            else if (obj.GetType() != typeof(Array3x2))
            {
                return false;
            }
            else
            {
                return this.Equals((Array3x2)obj);
            }
        }

        public override int GetHashCode()
        {
            return HashCode.Combine(row1, row2, row3);
        }

        public override string ToString()
        {
            return $"{row1}\n{row2}\n{row3}";
        }

        public static unsafe Array3x3 operator *(Array3x2 array1, Array2x3 array2)
        {
            float* p1 = &array1.row1.X;
            float* p2 = &array2.row2.X;

            return new Array3x3(
                *(p1 + 0) * *(p2 + 0) + *(p1 + 1) * *(p2 + 3),
                *(p1 + 0) * *(p2 + 1) + *(p1 + 1) * *(p2 + 4),
                *(p1 + 0) * *(p2 + 2) + *(p1 + 1) * *(p2 + 5),
                *(p1 + 2) * *(p2 + 0) + *(p1 + 3) * *(p2 + 3),
                *(p1 + 2) * *(p2 + 1) + *(p1 + 3) * *(p2 + 4),
                *(p1 + 2) * *(p2 + 2) + *(p1 + 3) * *(p2 + 5),
                *(p1 + 4) * *(p2 + 0) + *(p1 + 5) * *(p2 + 3),
                *(p1 + 4) * *(p2 + 1) + *(p1 + 5) * *(p2 + 4),
                *(p1 + 4) * *(p2 + 2) + *(p1 + 5) * *(p2 + 5)
                );
        }

    }
}