using System;
using NW4RTools;
using NW4RTools.Models;
using OpenTK;
using OpenTK.Graphics;
using OpenTK.Graphics.OpenGL;

namespace NW4RTools.Models.OpenGL {
	public class GLTexture : IDisposable {
		public readonly int TextureID;

		public GLTexture() {
			TextureID = GL.GenTexture();
		}

		void IDisposable.Dispose() {
			GL.DeleteTexture(TextureID);
		}

		public void Load(Texture tex) {
			Bind(TextureTarget.Texture2D);

			// todo: check if this is configurable
			GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);
			GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)TextureMagFilter.Linear);

			//byte[] pixelData = new byte[tex.BaseImage.Width * tex.BaseImage.Height * 4];

			var lb = tex.BaseImage.LockBits(
				new System.Drawing.Rectangle(0, 0, tex.BaseImage.Width, tex.BaseImage.Height),
				System.Drawing.Imaging.ImageLockMode.ReadOnly,
				System.Drawing.Imaging.PixelFormat.Format32bppArgb);

			GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Four,
				tex.BaseImage.Width, tex.BaseImage.Height, 0,
				PixelFormat.Bgra, PixelType.UnsignedByte, lb.Scan0);

			tex.BaseImage.UnlockBits(lb);
		}

		public void Bind(TextureTarget target) {
			GL.BindTexture(target, TextureID);
		}
	}
}