using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework;
using System.IO;

namespace GLEED2D
{
    //Copied from http://forums.create.msdn.com/forums/t/72423.aspx
    public static class ExtensionMethods
    {
        public static Texture2D ConvertToPreMultipliedAlpha(this Texture2D texture)
        {
            Color[] data = new Color[texture.Width * texture.Height];
            texture.GetData<Color>(data, 0, data.Length);
            for (int i = 0; i < data.Length; i++)
            {
                data[i] = new Color(new Vector4(data[i].ToVector3() * (data[i].A / 255f), (data[i].A / 255f)));
            }
            texture.SetData<Color>(data, 0, data.Length);

            return texture;
        }
    }  
    class TextureLoader
    {

        private static TextureLoader instance;
        public static TextureLoader Instance
        {
            get
            {
                if (instance == null) instance = new TextureLoader();
                return instance;
            }
        }

        Dictionary<string, Texture2D> textures = new Dictionary<string, Texture2D>();



        public Texture2D FromFile(GraphicsDevice gd, string filename)
        {
            if (!textures.ContainsKey(filename))
            {
                //TextureCreationParameters tcp = TextureCreationParameters.Default;
                //tcp.Format = SurfaceFormat.Color;
                //tcp.ColorKey = Constants.Instance.ColorTextureTransparent;
                //textures[filename] = Texture2D.FromFile(gd, filename, tcp);
                //using (Stream stream = File.Open(filename, FileMode.Open, FileAccess.Read, FileShare.None))
                //{
                StreamReader stream = new StreamReader(filename);

                textures[filename] = Texture2D.FromStream(gd, stream.BaseStream).ConvertToPreMultipliedAlpha();
                stream.Close();
                //}
            }
            return textures[filename];
        }

        public void Clear()
        {
            textures.Clear();
        }

    }
}