using UnityEngine;
using System.Collections;
using System.IO;
using LuaInterface;

public static class TakeScreenShot
{
    static string screenshotpath, thumbpath;
    static Texture2D screenShot;
    static Texture2D thumb;
    static int w, h;
    static TakeScreenShot()
    {
        screenshotpath = Application.persistentDataPath + "/screenshot.jpg";
        thumbpath = Application.persistentDataPath + "/screenshot_thumb.jpg";
    }
  
    public static void Take(LuaFunction callback)
    {
        if (FileExist(screenshotpath))
        {
            File.Delete(screenshotpath);
        }
        if (FileExist(screenshotpath))
        {
            File.Delete(screenshotpath);
        }
        GameApplication.Instance.StartCoroutine(CheckFile(callback));
    }

    static IEnumerator CheckFile(LuaFunction callback)
    {
        if (FileExist(screenshotpath) && FileExist(thumbpath))
        {
            yield return new WaitForEndOfFrame();
            GameApplication.Instance.StartCoroutine(CheckFile(callback));
        }
        else
        {
            yield return new WaitForEndOfFrame();
            screenShot = new Texture2D(Screen.width, Screen.height, TextureFormat.RGB24, false);
            Rect r = new Rect(0, 0, Screen.width, Screen.height);
            screenShot.ReadPixels(r, 0, 0, false);
            screenShot.Apply();

            if (Screen.orientation == ScreenOrientation.Landscape)
            {
                //480
                w = 240;
                h = (int)(240f * (float)Screen.height / (float)Screen.width);
            }
            else
            {
                //270
                w = 134;
                h = (int)(134f * (float)Screen.height / (float)Screen.width);
            }
            
            thumb = ScaleTexture(screenShot, w, h);
            byte[] screenshotdata = screenShot.EncodeToJPG(80);
            byte[] thumbdata = thumb.EncodeToJPG(60);
            File.WriteAllBytes(screenshotpath, screenshotdata);
            File.WriteAllBytes(thumbpath, thumbdata);
            if (callback != null)
            {
                callback.Call();
                callback.Dispose();
            }
        }
    }

    static Texture2D ScaleTexture(Texture2D source, int targetWidth, int targetHeight)
    {
        Texture2D result = new Texture2D(targetWidth, targetHeight, source.format, false);
        //float incX = (1.0f / (float)targetWidth);
        //float incY = (1.0f / (float)targetHeight);
        for (int i = 0; i < result.height; ++i)
        {
            for (int j = 0; j < result.width; ++j)
            {
                Color newColor = source.GetPixelBilinear((float)j / (float)result.width, (float)i / (float)result.height);
                result.SetPixel(j, i, newColor);
            }
        }  

        result.Apply();
        return result;
    }

    static bool FileExist(string path)
    {
        return File.Exists(path);
    }
}