package example.com.velezguiatour;

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.widget.ImageView;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Collections;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ImageLoader
{
    
    MemoryCache memoryCache = new MemoryCache();
    FileCache fileCache;
    private Map<ImageView, String> imageViews=Collections.synchronizedMap(new WeakHashMap<ImageView, String>());
    ExecutorService executorService; 
    
    public ImageLoader(Context context)
    {
        fileCache = new FileCache(context);
        executorService = Executors.newFixedThreadPool(5);
    }
    
    final int stub_id = R.drawable.stub;
    public void DisplayImage(String url, ImageView imageView, int defaultResource)
    {
        imageViews.put(imageView, url);
        Bitmap bitmap = memoryCache.get(url);
        if(bitmap != null)
        {
        	imageView.setImageBitmap(bitmap);
        }
        else
        {
            imageView.setImageResource(defaultResource);
        }
    }
        
    
    
    private Bitmap getBitmap(String url) 
    {
        File f = fileCache.getFile(url);
        
        //from SD cache
        Bitmap b = decodeFile(f);
        if(b!=null)
        {
            return b;
        }
        
        //from web
        try
        {
            Bitmap bitmap=null;
            URL imageUrl = new URL(url);
            HttpURLConnection conn = (HttpURLConnection)imageUrl.openConnection();
            conn.setConnectTimeout(30000);
            conn.setReadTimeout(30000);
            conn.setInstanceFollowRedirects(true);
            InputStream is=conn.getInputStream();
            OutputStream os = new FileOutputStream(f);
            Utils.CopyStream(is, os);
            os.close();
            bitmap = decodeFile(f);
            return bitmap;
        } 
        catch (Throwable ex)
        {
           ex.printStackTrace();
           if(ex instanceof OutOfMemoryError)
           {
        	   memoryCache.clear();
           }
           return null;
        }
    }

    private Bitmap decodeFile(File f)
    {
        try
        {
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            BitmapFactory.decodeStream(new FileInputStream(f),null,o);
            final int REQUIRED_SIZE = 70;
            int width_tmp = o.outWidth, height_tmp = o.outHeight;
            int scale = 1;
            while(true)
            {
                if(width_tmp/2<REQUIRED_SIZE || height_tmp/2<REQUIRED_SIZE)
                {
                	break;
                }
                width_tmp/=2;
                height_tmp/=2;
                scale*=2;
            }
            BitmapFactory.Options o2 = new BitmapFactory.Options();
            o2.inSampleSize = scale;
            return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
        } 
        catch (FileNotFoundException e)
        {       	
        }
        return null;
    }
    
    private class PhotoToLoad
    {
        public String url;
        public ImageView imageView;
        
    }
    
    class PhotosLoader implements Runnable
    {
        PhotoToLoad photoToLoad;
        PhotosLoader(PhotoToLoad photoToLoad)
        {
            this.photoToLoad = photoToLoad;
        }
        
        @Override public void run()
        {
            if(imageViewReused(photoToLoad))
            {
            	return;
            }
            Bitmap bmp = getBitmap(photoToLoad.url);
            memoryCache.put(photoToLoad.url, bmp);
            if(imageViewReused(photoToLoad))
            {
            	return;
            }
            BitmapDisplayer bd = new BitmapDisplayer(bmp, photoToLoad);
            Activity a = (Activity)photoToLoad.imageView.getContext();
            a.runOnUiThread(bd);
        }
    }
    
    boolean imageViewReused(PhotoToLoad photoToLoad)
    {
        String tag = imageViews.get(photoToLoad.imageView);
        if(tag == null || !tag.equals(photoToLoad.url))
        {
        	return true;
        }
        return false;
    }
    
    class BitmapDisplayer implements Runnable
    {
        Bitmap bitmap;
        PhotoToLoad photoToLoad;
        public BitmapDisplayer(Bitmap b, PhotoToLoad p){bitmap = b;photoToLoad = p;}
        public void run()
        {
            if(imageViewReused(photoToLoad))
            {
            	return;
            }
            if(bitmap != null)
            {
            	photoToLoad.imageView.setImageBitmap(bitmap);
            }
            else
            {
            	photoToLoad.imageView.setImageResource(stub_id);
            }
        }
    }

    public void clearCache()
    {
        memoryCache.clear();
        fileCache.clear();
    }

}
