content: /*******************************************************************************
   * Copyright 2011-2013 Sergey Tarasevich
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   *******************************************************************************/
  package com.nostra13.universalimageloader.utils;
  
  import android.content.Context;
  import android.content.pm.PackageManager;
  import android.os.Environment;
  
  import java.io.File;
  import java.io.IOException;
  
  import static android.os.Environment.MEDIA_MOUNTED;
  
  /**
   * Provides application storage paths
   *
   * @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
   * @since 1.0.0
   */
  public final class StorageUtils {
  
  	private static final String EXTERNAL_STORAGE_PERMISSION = "android.permission.WRITE_EXTERNAL_STORAGE";
  	private static final String INDIVIDUAL_DIR_NAME = "uil-images";
  
  	private StorageUtils() {
  	}
  
  	/**
  	 * Returns application cache directory. Cache directory will be created on SD card
  	 * <i>("/Android/data/[app_package_name]/cache")</i> if card is mounted and app has appropriate permission. Else -
  	 * Android defines cache directory on device's file system.
  	 *
  	 * @param context Application context
  	 * @return Cache {@link File directory}.<br />
  	 * <b>NOTE:</b> Can be null in some unpredictable cases (if SD card is unmounted and
  	 * {@link android.content.Context#getCacheDir() Context.getCacheDir()} returns null).
  	 */
  	public static File getCacheDirectory(Context context) {
  		return getCacheDirectory(context, true);
  	}
  
  	/**
  	 * Returns application cache directory. Cache directory will be created on SD card
  	 * <i>("/Android/data/[app_package_name]/cache")</i> (if card is mounted and app has appropriate permission) or
  	 * on device's file system depending incoming parameters.
  	 *
  	 * @param context        Application context
  	 * @param preferExternal Whether prefer external location for cache
  	 * @return Cache {@link File directory}.<br />
  	 * <b>NOTE:</b> Can be null in some unpredictable cases (if SD card is unmounted and
  	 * {@link android.content.Context#getCacheDir() Context.getCacheDir()} returns null).
  	 */
  	public static File getCacheDirectory(Context context, boolean preferExternal) {
  		File appCacheDir = null;
  		String externalStorageState;
  		try {
  			externalStorageState = Environment.getExternalStorageState();
  		} catch (NullPointerException e) { // (sh)it happens (Issue #660)
  			externalStorageState = "";
  		}
  		if (preferExternal && MEDIA_MOUNTED.equals(externalStorageState) && hasExternalStoragePermission(context)) {
  			appCacheDir = getExternalCacheDir(context);
  		}
  		if (appCacheDir == null) {
  			appCacheDir = context.getCacheDir();
  		}
  		if (appCacheDir == null) {
  			String cacheDirPath = "/data/data/" + context.getPackageName() + "/cache/";
  			L.w("Can't define system cache directory! '%s' will be used.", cacheDirPath);
  			appCacheDir = new File(cacheDirPath);
  		}
  		return appCacheDir;
  	}
  
  	/**
  	 * Returns individual application cache directory (for only image caching from ImageLoader). Cache directory will be
  	 * created on SD card <i>("/Android/data/[app_package_name]/cache/uil-images")</i> if card is mounted and app has
  	 * appropriate permission. Else - Android defines cache directory on device's file system.
  	 *
  	 * @param context Application context
  	 * @return Cache {@link File directory}
  	 */
  	public static File getIndividualCacheDirectory(Context context) {
  		File cacheDir = getCacheDirectory(context);
  		File individualCacheDir = new File(cacheDir, INDIVIDUAL_DIR_NAME);
  		if (!individualCacheDir.exists()) {
  			if (!individualCacheDir.mkdir()) {
  				individualCacheDir = cacheDir;
  			}
  		}
  		return individualCacheDir;
  	}
  
  	/**
  	 * Returns specified application cache directory. Cache directory will be created on SD card by defined path if card
  	 * is mounted and app has appropriate permission. Else - Android defines cache directory on device's file system.
  	 *
  	 * @param context  Application context
  	 * @param cacheDir Cache directory path (e.g.: "AppCacheDir", "AppDir/cache/images")
  	 * @return Cache {@link File directory}
  	 */
  	public static File getOwnCacheDirectory(Context context, String cacheDir) {
  		File appCacheDir = null;
  		if (MEDIA_MOUNTED.equals(Environment.getExternalStorageState()) && hasExternalStoragePermission(context)) {
  			appCacheDir = new File(Environment.getExternalStorageDirectory(), cacheDir);
  		}
  		if (appCacheDir == null || (!appCacheDir.exists() && !appCacheDir.mkdirs())) {
  			appCacheDir = context.getCacheDir();
  		}
  		return appCacheDir;
  	}
  
  	private static File getExternalCacheDir(Context context) {
  		File dataDir = new File(new File(Environment.getExternalStorageDirectory(), "Android"), "data");
  		File appCacheDir = new File(new File(dataDir, context.getPackageName()), "cache");
  		if (!appCacheDir.exists()) {
  			if (!appCacheDir.mkdirs()) {
  				L.w("Unable to create external cache directory");
  				return null;
  			}
  			try {
  				new File(appCacheDir, ".nomedia").createNewFile();
  			} catch (IOException e) {
  				L.i("Can't create \".nomedia\" file in application external cache directory");
  			}
  		}
  		return appCacheDir;
  	}
  
  	private static boolean hasExternalStoragePermission(Context context) {
  		int perm = context.checkCallingOrSelfPermission(EXTERNAL_STORAGE_PERMISSION);
  		return perm == PackageManager.PERMISSION_GRANTED;
  	}
  }
  