content: /*
   ===========================================================================
   Copyright (c) 2012 Three Pillar Global Inc. http://threepillarglobal.com
  
   Permission is hereby granted, free of charge, to any person obtaining a copy
   of this software and associated documentation files (the "Software"), to deal
   in the Software without restriction, including without limitation the rights
   to use, copy, modify, merge, publish, distribute, sub-license, and/or sell
   copies of the Software, and to permit persons to whom the Software is
   furnished to do so, subject to the following conditions:
  
   The above copyright notice and this permission notice shall be included in
   all copies or substantial portions of the Software.
  
   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   THE SOFTWARE.
   ===========================================================================
   */
  
  package org.brickred.customadapter;
  
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.FileNotFoundException;
  import java.io.FileOutputStream;
  import java.io.IOException;
  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;
  
  import android.content.Context;
  import android.graphics.Bitmap;
  import android.graphics.BitmapFactory;
  import android.graphics.Color;
  import android.graphics.drawable.ColorDrawable;
  import android.os.Handler;
  import android.util.Log;
  import android.widget.ImageView;
  
  /**
   * Class for loading image in gridview
   * 
   * @author Vineet Aggarwal
   * 
   */
  
  public class ImageLoader {
  
  	MemoryCache memoryCache = new MemoryCache();
  	FileCache fileCache;
  	private final Map<ImageView, String> imageViews = Collections.synchronizedMap(new WeakHashMap<ImageView, String>());
  	ExecutorService executorService;
  	Handler handler = new Handler();// handler to display images in UI thread
  
  	public ImageLoader(Context context) {
  		fileCache = new FileCache(context);
  		executorService = Executors.newFixedThreadPool(5);
  	}
  
  	public void DisplayImage(String url, ImageView imageView) {
  		imageViews.put(imageView, url);
  		Bitmap bitmap = memoryCache.get(url);
  		if (bitmap != null) {
  			imageView.setImageBitmap(bitmap);
  		} else {
  			queuePhoto(url, imageView);
  			imageView.setImageDrawable(new ColorDrawable(Color.WHITE));
  		}
  	}
  
  	private void queuePhoto(String url, ImageView imageView) {
  		PhotoToLoad p = new PhotoToLoad(url, imageView);
  		executorService.submit(new PhotosLoader(p));
  	}
  
  	private Bitmap getBitmap(String url, int size) {
  		File f = fileCache.getFile(url);
  
  		// from SD cache
  		Bitmap b = decodeFile(f, size);
  		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);
  			copyStream(is, os);
  			os.close();
  			bitmap = decodeFile(f, size);
  			return bitmap;
  		} catch (Throwable ex) {
  			ex.printStackTrace();
  			if (ex instanceof OutOfMemoryError)
  				memoryCache.clear();
  			return null;
  		}
  	}
  
  	// decodes image and scales it to reduce memory consumption
  	private Bitmap decodeFile(File f, int size) {
  		try {
  			// decode image size
  			BitmapFactory.Options o = new BitmapFactory.Options();
  			o.inJustDecodeBounds = true;
  			FileInputStream stream1 = new FileInputStream(f);
  			BitmapFactory.decodeStream(stream1, null, o);
  			stream1.close();
  
  			int width_tmp = o.outWidth, height_tmp = o.outHeight;
  
  			int scale = 1;
  
  			// Find the correct scale value. It should be the power of 2.
  			final int REQUIRED_SIZE = size;
  			while (true) {
  				if (width_tmp / 2 < REQUIRED_SIZE || height_tmp / 2 < REQUIRED_SIZE)
  					break;
  				width_tmp /= 2;
  				height_tmp /= 2;
  				scale *= 2;
  			}
  
  			// decode with inSampleSize
  			BitmapFactory.Options o2 = new BitmapFactory.Options();
  			o2.inJustDecodeBounds = false;
  			o2.inSampleSize = scale;
  			o2.inDither = true;
  			o2.inScaled = false;
  			o2.inPreferredConfig = Bitmap.Config.ARGB_8888;
  			o2.inPurgeable = true;
  			FileInputStream stream2 = new FileInputStream(f);
  			Bitmap bitmap = BitmapFactory.decodeStream(stream2, null, o2);
  			Log.d("Bitmap Width", String.valueOf(o2.outWidth));
  			Log.d("Bitmap Height", String.valueOf(o2.outHeight));
  
  			stream2.close();
  
  			return bitmap;
  
  		} catch (FileNotFoundException e) {
  		} catch (IOException e) {
  			e.printStackTrace();
  		}
  		return null;
  	}
  
  	// Task for the queue
  	private class PhotoToLoad {
  		public String url;
  		public ImageView imageView;
  
  		public PhotoToLoad(String u, ImageView i) {
  			url = u;
  			imageView = i;
  		}
  	}
  
  	class PhotosLoader implements Runnable {
  		PhotoToLoad photoToLoad;
  
  		PhotosLoader(PhotoToLoad photoToLoad) {
  			this.photoToLoad = photoToLoad;
  		}
  
  		@Override
  		public void run() {
  			try {
  				if (imageViewReused(photoToLoad))
  					return;
  				Bitmap bmp = getBitmap(photoToLoad.url, 70);
  				memoryCache.put(photoToLoad.url, bmp);
  				if (imageViewReused(photoToLoad))
  					return;
  				BitmapDisplayer bd = new BitmapDisplayer(bmp, photoToLoad);
  				handler.post(bd);
  			} catch (Throwable th) {
  				th.printStackTrace();
  			}
  		}
  	}
  
  	boolean imageViewReused(PhotoToLoad photoToLoad) {
  		String tag = imageViews.get(photoToLoad.imageView);
  		if (tag == null || !tag.equals(photoToLoad.url))
  			return true;
  		return false;
  	}
  
  	// Used to display bitmap in the UI thread
  	class BitmapDisplayer implements Runnable {
  		Bitmap bitmap;
  		PhotoToLoad photoToLoad;
  
  		public BitmapDisplayer(Bitmap b, PhotoToLoad p) {
  			bitmap = b;
  			photoToLoad = p;
  		}
  
  		@Override
  		public void run() {
  			if (imageViewReused(photoToLoad))
  				return;
  			if (bitmap != null)
  				photoToLoad.imageView.setImageBitmap(bitmap);
  			else
  				photoToLoad.imageView.setImageDrawable(new ColorDrawable(Color.WHITE));
  		}
  	}
  
  	public void clearCache() {
  		memoryCache.clear();
  		fileCache.clear();
  	}
  
  	public void copyStream(InputStream is, OutputStream os) {
  		final int buffer_size = 1024;
  		try {
  			byte[] bytes = new byte[buffer_size];
  			for (;;) {
  				int count = is.read(bytes, 0, buffer_size);
  				if (count == -1)
  					break;
  				os.write(bytes, 0, count);
  			}
  		} catch (Exception ex) {
  		}
  	}
  
  }
  