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

namespace StgSharp.Graphics
{
    public unsafe struct VertexBuffer : IDisposable
    {
        internal uint _bufferID;

        public VertexBuffer(int n)
        {
            fixed (uint* id = &_bufferID)
            {
                Graphic.glGenBuffers(n, id);
            }

        }

        public uint BufferID
        {
            get { return _bufferID; }
        }
        public void Bind()
        {
            Graphic.glBindBuffer(GLFW.GL_ARRAY_BUFFER, _bufferID);
        }

        public void Dispose()
        {
            fixed (uint* id = &_bufferID)
            {
                Graphic.glDeleteBuffers(1, id);
            }
        }

        public void SetData<T>(T bufferData, BufferReadType readType) where T : IMat
        {
            int size = Marshal.SizeOf(bufferData);
            Graphic.glBufferData(
                (int)BufferType.ARRAY_BUFFER,
                size,
                &bufferData,
                (int)readType);
        }

        public void SetData<T>(T[] bufferArray, BufferReadType readType) where T : struct, IConvertible
        {

            int size = bufferArray.Length * Marshal.SizeOf(typeof(T));

            fixed (void* bufferPtr = &bufferArray[0])
                Graphic.glBufferData(
                    (int)BufferType.ARRAY_BUFFER,
                    size,
                    bufferPtr,
                    (int)readType);
        }
    }
}