1 files changed, 77 insertions, 588 deletions

diff --git a/src/main/java/eu/siacs/conversations/persistance/FileBackend.java b/src/main/java/eu/siacs/conversations/persistance/FileBackend.java
index db48c8b3..8abbb0cb 100644
--- a/src/main/java/eu/siacs/conversations/persistance/FileBackend.java
+++ b/src/main/java/eu/siacs/conversations/persistance/FileBackend.java
@@ -1,65 +1,61 @@
 package eu.siacs.conversations.persistance;
 
-import android.annotation.TargetApi;
-import android.content.ContentResolver;
-import android.content.Context;
 import android.content.Intent;
-import android.database.Cursor;
 import android.graphics.Bitmap;
-import android.graphics.BitmapFactory;
-import android.graphics.Canvas;
-import android.graphics.Matrix;
-import android.graphics.RectF;
 import android.net.Uri;
-import android.os.Build;
 import android.os.Environment;
-import android.os.ParcelFileDescriptor;
-import android.provider.OpenableColumns;
-import android.system.Os;
-import android.system.StructStat;
-import android.util.Base64;
-import android.util.Base64OutputStream;
 import android.util.Log;
-import android.util.LruCache;
 import android.webkit.MimeTypeMap;
 
-import java.io.ByteArrayOutputStream;
-import java.io.Closeable;
 import java.io.File;
-import java.io.FileDescriptor;
-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.Socket;
-import java.net.URL;
-import java.security.DigestOutputStream;
-import java.security.MessageDigest;
-import java.security.NoSuchAlgorithmException;
 import java.text.SimpleDateFormat;
 import java.util.Date;
-import java.util.List;
 import java.util.Locale;
 
+import de.thedevstack.android.logcat.Logging;
+import de.thedevstack.conversationsplus.ConversationsPlusApplication;
+import de.thedevstack.conversationsplus.ConversationsPlusPreferences;
+import de.thedevstack.conversationsplus.exceptions.FileCopyException;
+import de.thedevstack.conversationsplus.persistance.observers.FileDeletionObserver;
+import de.thedevstack.conversationsplus.utils.StreamUtil;
 import eu.siacs.conversations.Config;
 import eu.siacs.conversations.R;
 import eu.siacs.conversations.entities.DownloadableFile;
 import eu.siacs.conversations.entities.Message;
 import eu.siacs.conversations.services.XmppConnectionService;
-import eu.siacs.conversations.utils.CryptoHelper;
-import eu.siacs.conversations.utils.ExifHelper;
-import eu.siacs.conversations.utils.FileUtils;
-import eu.siacs.conversations.xmpp.pep.Avatar;
 
 public class FileBackend {
-	private final SimpleDateFormat imageDateFormat = new SimpleDateFormat("yyyyMMdd_HHmmssSSS", Locale.US);
+	private static final SimpleDateFormat imageDateFormat = new SimpleDateFormat("yyyyMMdd_HHmmssSSS", Locale.US);
+    private static FileBackend INSTANCE;
 
-	private XmppConnectionService mXmppConnectionService;
+    private FileDeletionObserver privateFilesDirectoryObserver;
+    private FileDeletionObserver privateFilesImageDirectoryObserver;
+    private FileDeletionObserver conversationsFilesDirectoryObserver;
+    private FileDeletionObserver conversationsImagesDirectoryObserver;
 
-	public FileBackend(XmppConnectionService service) {
-		this.mXmppConnectionService = service;
+    public static void init() {
+        if (null == INSTANCE) {
+            INSTANCE = new FileBackend();
+        }
+        INSTANCE.initFileObservers();
+        INSTANCE.createNoMedia();
+    }
+
+    private void initFileObservers() {
+        this.privateFilesDirectoryObserver = new FileDeletionObserver(FileBackend.getPrivateFileDirectoryPath());
+        this.privateFilesImageDirectoryObserver = new FileDeletionObserver(FileBackend.getConversationsFileDirectory());
+        this.conversationsFilesDirectoryObserver = new FileDeletionObserver(FileBackend.getConversationsImageDirectory());
+        this.conversationsImagesDirectoryObserver = new FileDeletionObserver(FileBackend.getPrivateImageDirectoryPath());
+
+        this.privateFilesDirectoryObserver.startWatching();
+        this.privateFilesImageDirectoryObserver.startWatching();
+        this.conversationsFilesDirectoryObserver.startWatching();
+        this.conversationsImagesDirectoryObserver.startWatching();
     }
 
 	private void createNoMedia() {
@@ -73,31 +69,42 @@ public class FileBackend {
 		}
 	}
 
-	public void updateMediaScanner(File file) {
+    public static void onFileTransferFolderChanged() {
+        INSTANCE.conversationsFilesDirectoryObserver.stopWatching();
+        INSTANCE.conversationsFilesDirectoryObserver = new FileDeletionObserver(FileBackend.getConversationsFileDirectory());
+        INSTANCE.conversationsFilesDirectoryObserver.startWatching();
+        INSTANCE.createNoMedia();
+    }
+
+    public static void onImageTransferFolderChanged() {
+        INSTANCE.conversationsImagesDirectoryObserver.stopWatching();
+        INSTANCE.conversationsImagesDirectoryObserver = new FileDeletionObserver(FileBackend.getConversationsImageDirectory());
+        INSTANCE.conversationsImagesDirectoryObserver.startWatching();
+    }
+
+	public static void updateMediaScanner(File file, XmppConnectionService xmppConnectionService) {
 		if (file.getAbsolutePath().startsWith(getConversationsImageDirectory())) {
 			Intent intent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
 			intent.setData(Uri.fromFile(file));
-			mXmppConnectionService.sendBroadcast(intent);
-		} else {
-			createNoMedia();
+			xmppConnectionService.sendBroadcast(intent);
 		}
 	}
 
-	public boolean deleteFile(Message message) {
+	public static boolean deleteFile(Message message, XmppConnectionService xmppConnectionService) {
 		File file = getFile(message);
 		if (file.delete()) {
-			updateMediaScanner(file);
+			updateMediaScanner(file, xmppConnectionService);
 			return true;
 		} else {
 			return false;
 		}
 	}
 
-	public DownloadableFile getFile(Message message) {
+	public static DownloadableFile getFile(Message message) {
 		return getFile(message, true);
 	}
 
-	public DownloadableFile getFile(Message message, boolean decrypted) {
+	public static DownloadableFile getFile(Message message, boolean decrypted) {
 		final boolean encrypted = !decrypted
 				&& (message.getEncryption() == Message.ENCRYPTION_PGP
 				|| message.getEncryption() == Message.ENCRYPTION_DECRYPTED);
@@ -123,112 +130,30 @@ public class FileBackend {
 		}
 	}
 
-	private static long getFileSize(Context context, Uri uri) {
-		Cursor cursor = context.getContentResolver().query(uri, null, null, null, null);
-		if (cursor != null && cursor.moveToFirst()) {
-			return cursor.getLong(cursor.getColumnIndex(OpenableColumns.SIZE));
-		} else {
-			return -1;
-		}
-	}
-
-	public static boolean allFilesUnderSize(Context context, List<Uri> uris, long max) {
-		if (max <= 0) {
-			Log.d(Config.LOGTAG,"server did not report max file size for http upload");
-			return true; //exception to be compatible with HTTP Upload < v0.2
-		}
-		for(Uri uri : uris) {
-			if (FileBackend.getFileSize(context, uri) > max) {
-				Log.d(Config.LOGTAG,"not all files are under "+max+" bytes. suggesting falling back to jingle");
-				return false;
-			}
-		}
-		return true;
-	}
-
 	public static String getConversationsFileDirectory() {
-		return  Environment.getExternalStorageDirectory().getAbsolutePath()+"/Conversations/";
+		return  Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator + ConversationsPlusPreferences.fileTransferFolder() + File.separator;
 	}
 
 	public static String getConversationsImageDirectory() {
-		return Environment.getExternalStoragePublicDirectory(
-				Environment.DIRECTORY_PICTURES).getAbsolutePath()
-			+ "/Conversations/";
+		return Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).getAbsolutePath() + File.separator + ConversationsPlusPreferences.imgTransferFolder() + File.separator;
 	}
 
-	public Bitmap resize(Bitmap originalBitmap, int size) {
-		int w = originalBitmap.getWidth();
-		int h = originalBitmap.getHeight();
-		if (Math.max(w, h) > size) {
-			int scalledW;
-			int scalledH;
-			if (w <= h) {
-				scalledW = (int) (w / ((double) h / size));
-				scalledH = size;
-			} else {
-				scalledW = size;
-				scalledH = (int) (h / ((double) w / size));
-			}
-			Bitmap result = Bitmap.createScaledBitmap(originalBitmap, scalledW, scalledH, true);
-			if (originalBitmap != null && !originalBitmap.isRecycled()) {
-				originalBitmap.recycle();
-			}
-			return result;
-		} else {
-			return originalBitmap;
-		}
+    public static String getPrivateFileDirectoryPath() {
+        return ConversationsPlusApplication.getPrivateFilesDir().getAbsolutePath();
     }
 
-	public static Bitmap rotate(Bitmap bitmap, int degree) {
-		if (degree == 0) {
-			return bitmap;
-		}
-		int w = bitmap.getWidth();
-		int h = bitmap.getHeight();
-		Matrix mtx = new Matrix();
-		mtx.postRotate(degree);
-		Bitmap result = Bitmap.createBitmap(bitmap, 0, 0, w, h, mtx, true);
-		if (bitmap != null && !bitmap.isRecycled()) {
-			bitmap.recycle();
-		}
-		return result;
+    private static String getPrivateImageDirectoryPath() {
+        return FileBackend.getPrivateFileDirectoryPath() + File.separator + "Images" + File.separator;
     }
 
-	public boolean useImageAsIs(Uri uri) {
-		String path = getOriginalPath(uri);
-		if (path == null) {
-			return false;
-		}
-		File file = new File(path);
-		long size = file.length();
-		if (size == 0 || size >= Config.IMAGE_MAX_SIZE ) {
-			return false;
-		}
-		BitmapFactory.Options options = new BitmapFactory.Options();
-		options.inJustDecodeBounds = true;
-		try {
-			BitmapFactory.decodeStream(mXmppConnectionService.getContentResolver().openInputStream(uri), null, options);
-			if (options == null || options.outMimeType == null || options.outHeight <= 0 || options.outWidth <= 0) {
-				return false;
-			}
-			return (options.outWidth <= Config.IMAGE_SIZE && options.outHeight <= Config.IMAGE_SIZE && options.outMimeType.contains(Config.IMAGE_FORMAT.name().toLowerCase()));
-		} catch (FileNotFoundException e) {
-			return false;
-		}
-	}
-
-	public String getOriginalPath(Uri uri) {
-		return FileUtils.getPath(mXmppConnectionService,uri);
-	}
-
-	public void copyFileToPrivateStorage(File file, Uri uri) throws FileCopyException {
+	public static void copyFileToPrivateStorage(File file, Uri uri) throws FileCopyException {
 		file.getParentFile().mkdirs();
 		OutputStream os = null;
 		InputStream is = null;
 		try {
 			file.createNewFile();
 			os = new FileOutputStream(file);
-			is = mXmppConnectionService.getContentResolver().openInputStream(uri);
+			is = StreamUtil.openInputStreamFromContentResolver(uri);
 			byte[] buffer = new byte[1024];
 			int length;
 			while ((length = is.read(buffer)) > 0) {
@@ -241,505 +166,69 @@ public class FileBackend {
 			e.printStackTrace();
 			throw new FileCopyException(R.string.error_io_exception);
 		} finally {
-			close(os);
-			close(is);
+			StreamUtil.close(os);
+			StreamUtil.close(is);
 		}
-		Log.d(Config.LOGTAG, "output file name " + file.getAbsolutePath());
+		Logging.d(Config.LOGTAG, "output file name " + file);
 	}
 
-	public void copyFileToPrivateStorage(Message message, Uri uri) throws FileCopyException {
+	public static void copyFileToPrivateStorage(Message message, Uri uri) throws FileCopyException {
 		Log.d(Config.LOGTAG, "copy " + uri.toString() + " to private storage");
-		String mime = mXmppConnectionService.getContentResolver().getType(uri);
+		String mime = ConversationsPlusApplication.getInstance().getContentResolver().getType(uri);
 		String extension = MimeTypeMap.getSingleton().getExtensionFromMimeType(mime);
 		message.setRelativeFilePath(message.getUuid() + "." + extension);
-		copyFileToPrivateStorage(mXmppConnectionService.getFileBackend().getFile(message), uri);
+		copyFileToPrivateStorage(getFile(message), uri);
 	}
 
-	private void copyImageToPrivateStorage(File file, Uri image, int sampleSize) throws FileCopyException {
+    public static DownloadableFile compressImageAndCopyToPrivateStorage(Message message, Bitmap scaledBitmap) throws FileCopyException {
+        message.setRelativeFilePath(FileBackend.getPrivateImageDirectoryPath() + message.getUuid() + ".jpg");
+        DownloadableFile file = getFile(message);
         file.getParentFile().mkdirs();
-		InputStream is = null;
         OutputStream os = null;
         try {
             file.createNewFile();
-			is = mXmppConnectionService.getContentResolver().openInputStream(image);
-			Bitmap originalBitmap;
-			BitmapFactory.Options options = new BitmapFactory.Options();
-			int inSampleSize = (int) Math.pow(2, sampleSize);
-			Log.d(Config.LOGTAG, "reading bitmap with sample size " + inSampleSize);
-			options.inSampleSize = inSampleSize;
-			originalBitmap = BitmapFactory.decodeStream(is, null, options);
-			is.close();
-			if (originalBitmap == null) {
-				throw new FileCopyException(R.string.error_not_an_image_file);
-			}
-			Bitmap scaledBitmap = resize(originalBitmap, Config.IMAGE_SIZE);
-			int rotation = getRotation(image);
-			scaledBitmap = rotate(scaledBitmap, rotation);
-			boolean targetSizeReached = false;
-			int quality = Config.IMAGE_QUALITY;
-			while(!targetSizeReached) {
             os = new FileOutputStream(file);
-				boolean success = scaledBitmap.compress(Config.IMAGE_FORMAT, quality, os);
+
+            boolean success = scaledBitmap.compress(Bitmap.CompressFormat.JPEG, 75, os);
             if (!success) {
                 throw new FileCopyException(R.string.error_compressing_image);
             }
             os.flush();
-				targetSizeReached = file.length() <= Config.IMAGE_MAX_SIZE || quality <= 50;
-				quality -= 5;
-			}
-			scaledBitmap.recycle();
-			return;
-		} catch (FileNotFoundException e) {
-			throw new FileCopyException(R.string.error_file_not_found);
         } catch (IOException e) {
-			e.printStackTrace();
-			throw new FileCopyException(R.string.error_io_exception);
+            throw new FileCopyException(R.string.error_io_exception, e);
         } catch (SecurityException e) {
             throw new FileCopyException(R.string.error_security_exception_during_image_copy);
-		} catch (OutOfMemoryError e) {
-			++sampleSize;
-			if (sampleSize <= 3) {
-				copyImageToPrivateStorage(file, image, sampleSize);
-			} else {
-				throw new FileCopyException(R.string.error_out_of_memory);
-			}
         } catch (NullPointerException e) {
             throw new FileCopyException(R.string.error_io_exception);
         } finally {
-			close(os);
-			close(is);
+            StreamUtil.close(os);
         }
+        return file;
     }
 
-	public void copyImageToPrivateStorage(File file, Uri image) throws FileCopyException {
-		copyImageToPrivateStorage(file, image, 0);
-	}
-
-	public void copyImageToPrivateStorage(Message message, Uri image) throws FileCopyException {
-		switch(Config.IMAGE_FORMAT) {
-			case JPEG:
-				message.setRelativeFilePath(message.getUuid()+".jpg");
-				break;
-			case PNG:
-				message.setRelativeFilePath(message.getUuid()+".png");
-				break;
-			case WEBP:
-				message.setRelativeFilePath(message.getUuid()+".webp");
-				break;
-		}
-		copyImageToPrivateStorage(getFile(message), image);
-		updateFileParams(message);
-	}
-
-	private int getRotation(File file) {
-		return getRotation(Uri.parse("file://"+file.getAbsolutePath()));
-	}
-
-	private int getRotation(Uri image) {
-		InputStream is = null;
-		try {
-			is = mXmppConnectionService.getContentResolver().openInputStream(image);
-			return ExifHelper.getOrientation(is);
-		} catch (FileNotFoundException e) {
-			return 0;
-		} finally {
-			close(is);
-		}
-	}
-
-	public Bitmap getThumbnail(Message message, int size, boolean cacheOnly) throws FileNotFoundException {
-		final String uuid = message.getUuid();
-		final LruCache<String,Bitmap> cache = mXmppConnectionService.getBitmapCache();
-		Bitmap thumbnail = cache.get(uuid);
-		if ((thumbnail == null) && (!cacheOnly)) {
-			synchronized (cache) {
-				thumbnail = cache.get(uuid);
-				if (thumbnail != null) {
-					return thumbnail;
-				}
-				File file = getFile(message);
-				BitmapFactory.Options options = new BitmapFactory.Options();
-				options.inSampleSize = calcSampleSize(file, size);
-				Bitmap fullsize = BitmapFactory.decodeFile(file.getAbsolutePath(), options);
-				if (fullsize == null) {
-					throw new FileNotFoundException();
-				}
-				thumbnail = resize(fullsize, size);
-				thumbnail = rotate(thumbnail, getRotation(file));
-				this.mXmppConnectionService.getBitmapCache().put(uuid, thumbnail);
-			}
-		}
-		return thumbnail;
-	}
-
-	public Uri getTakePhotoUri() {
+	public static Uri getTakePhotoUri() {
 		StringBuilder pathBuilder = new StringBuilder();
 		pathBuilder.append(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM));
 		pathBuilder.append('/');
 		pathBuilder.append("Camera");
 		pathBuilder.append('/');
-		pathBuilder.append("IMG_" + this.imageDateFormat.format(new Date()) + ".jpg");
+		pathBuilder.append("IMG_" + imageDateFormat.format(new Date()) + ".jpg");
 		Uri uri = Uri.parse("file://" + pathBuilder.toString());
 		File file = new File(uri.toString());
 		file.getParentFile().mkdirs();
 		return uri;
 	}
 
-	public Avatar getPepAvatar(Uri image, int size, Bitmap.CompressFormat format) {
-		try {
-			Avatar avatar = new Avatar();
-			Bitmap bm = cropCenterSquare(image, size);
-			if (bm == null) {
-				return null;
-			}
-			ByteArrayOutputStream mByteArrayOutputStream = new ByteArrayOutputStream();
-			Base64OutputStream mBase64OutputSttream = new Base64OutputStream(
-					mByteArrayOutputStream, Base64.DEFAULT);
-			MessageDigest digest = MessageDigest.getInstance("SHA-1");
-			DigestOutputStream mDigestOutputStream = new DigestOutputStream(
-					mBase64OutputSttream, digest);
-			if (!bm.compress(format, 75, mDigestOutputStream)) {
-				return null;
-			}
-			mDigestOutputStream.flush();
-			mDigestOutputStream.close();
-			avatar.sha1sum = CryptoHelper.bytesToHex(digest.digest());
-			avatar.image = new String(mByteArrayOutputStream.toByteArray());
-			return avatar;
-		} catch (NoSuchAlgorithmException e) {
-			return null;
-		} catch (IOException e) {
-			return null;
-		}
-	}
-
-	public Avatar getStoredPepAvatar(String hash) {
-		if (hash == null) {
-			return null;
-		}
-		Avatar avatar = new Avatar();
-		File file = new File(getAvatarPath(hash));
-		FileInputStream is = null;
-		try {
-			BitmapFactory.Options options = new BitmapFactory.Options();
-			options.inJustDecodeBounds = true;
-			BitmapFactory.decodeFile(file.getAbsolutePath(), options);
-			is = new FileInputStream(file);
-			ByteArrayOutputStream mByteArrayOutputStream = new ByteArrayOutputStream();
-			Base64OutputStream mBase64OutputStream = new Base64OutputStream(mByteArrayOutputStream, Base64.DEFAULT);
-			MessageDigest digest = MessageDigest.getInstance("SHA-1");
-			DigestOutputStream os = new DigestOutputStream(mBase64OutputStream, digest);
-			byte[] buffer = new byte[4096];
-			int length;
-			while ((length = is.read(buffer)) > 0) {
-				os.write(buffer, 0, length);
-			}
-			os.flush();
-			os.close();
-			avatar.sha1sum = CryptoHelper.bytesToHex(digest.digest());
-			avatar.image = new String(mByteArrayOutputStream.toByteArray());
-			avatar.height = options.outHeight;
-			avatar.width = options.outWidth;
-			return avatar;
-		} catch (IOException e) {
-			return null;
-		} catch (NoSuchAlgorithmException e) {
-			return null;
-		} finally {
-			close(is);
-		}
-	}
-
-	public boolean isAvatarCached(Avatar avatar) {
-		File file = new File(getAvatarPath(avatar.getFilename()));
-		return file.exists();
-	}
-
-	public boolean save(Avatar avatar) {
-		File file;
-		if (isAvatarCached(avatar)) {
-			file = new File(getAvatarPath(avatar.getFilename()));
-		} else {
-			String filename = getAvatarPath(avatar.getFilename());
-			file = new File(filename + ".tmp");
-			file.getParentFile().mkdirs();
-			OutputStream os = null;
-			try {
-				file.createNewFile();
-				os = new FileOutputStream(file);
-				MessageDigest digest = MessageDigest.getInstance("SHA-1");
-				digest.reset();
-				DigestOutputStream mDigestOutputStream = new DigestOutputStream(os, digest);
-				mDigestOutputStream.write(avatar.getImageAsBytes());
-				mDigestOutputStream.flush();
-				mDigestOutputStream.close();
-				String sha1sum = CryptoHelper.bytesToHex(digest.digest());
-				if (sha1sum.equals(avatar.sha1sum)) {
-					file.renameTo(new File(filename));
-				} else {
-					Log.d(Config.LOGTAG, "sha1sum mismatch for " + avatar.owner);
-					file.delete();
-					return false;
-				}
-			} catch (IllegalArgumentException | IOException | NoSuchAlgorithmException e) {
-				return false;
-			} finally {
-				close(os);
-			}
-		}
-		avatar.size = file.length();
-		return true;
-	}
-
-	public String getAvatarPath(String avatar) {
-		return mXmppConnectionService.getFilesDir().getAbsolutePath()+ "/avatars/" + avatar;
-	}
-
-	public Uri getAvatarUri(String avatar) {
-		return Uri.parse("file:" + getAvatarPath(avatar));
-	}
-
-	public Bitmap cropCenterSquare(Uri image, int size) {
-		if (image == null) {
-			return null;
-		}
-		InputStream is = null;
-		try {
-			BitmapFactory.Options options = new BitmapFactory.Options();
-			options.inSampleSize = calcSampleSize(image, size);
-			is = mXmppConnectionService.getContentResolver().openInputStream(image);
-			if (is == null) {
-				return null;
-			}
-			Bitmap input = BitmapFactory.decodeStream(is, null, options);
-			if (input == null) {
-				return null;
-			} else {
-				input = rotate(input, getRotation(image));
-				return cropCenterSquare(input, size);
-			}
-		} catch (SecurityException e) {
-			return null; // happens for example on Android 6.0 if contacts permissions get revoked
-		} catch (FileNotFoundException e) {
-			return null;
-		} finally {
-			close(is);
-		}
-	}
-
-	public Bitmap cropCenter(Uri image, int newHeight, int newWidth) {
-		if (image == null) {
-			return null;
-		}
-		InputStream is = null;
-		try {
-			BitmapFactory.Options options = new BitmapFactory.Options();
-			options.inSampleSize = calcSampleSize(image, Math.max(newHeight, newWidth));
-			is = mXmppConnectionService.getContentResolver().openInputStream(image);
-			if (is == null) {
-				return null;
-			}
-			Bitmap source = BitmapFactory.decodeStream(is, null, options);
-			if (source == null) {
-				return null;
-			}
-			int sourceWidth = source.getWidth();
-			int sourceHeight = source.getHeight();
-			float xScale = (float) newWidth / sourceWidth;
-			float yScale = (float) newHeight / sourceHeight;
-			float scale = Math.max(xScale, yScale);
-			float scaledWidth = scale * sourceWidth;
-			float scaledHeight = scale * sourceHeight;
-			float left = (newWidth - scaledWidth) / 2;
-			float top = (newHeight - scaledHeight) / 2;
-
-			RectF targetRect = new RectF(left, top, left + scaledWidth, top + scaledHeight);
-			Bitmap dest = Bitmap.createBitmap(newWidth, newHeight, Bitmap.Config.ARGB_8888);
-			Canvas canvas = new Canvas(dest);
-			canvas.drawBitmap(source, null, targetRect, null);
-			if (source != null && !source.isRecycled()) {
-				source.recycle();
-			}
-			return dest;
-		} catch (SecurityException e) {
-			return null; //android 6.0 with revoked permissions for example
-		} catch (FileNotFoundException e) {
-			return null;
-		} finally {
-			close(is);
-		}
-	}
-
-	public Bitmap cropCenterSquare(Bitmap input, int size) {
-		int w = input.getWidth();
-		int h = input.getHeight();
-
-		float scale = Math.max((float) size / h, (float) size / w);
-
-		float outWidth = scale * w;
-		float outHeight = scale * h;
-		float left = (size - outWidth) / 2;
-		float top = (size - outHeight) / 2;
-		RectF target = new RectF(left, top, left + outWidth, top + outHeight);
-
-		Bitmap output = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888);
-		Canvas canvas = new Canvas(output);
-		canvas.drawBitmap(input, null, target, null);
-		if (input != null && !input.isRecycled()) {
-			input.recycle();
-		}
-		return output;
-	}
-
-	private int calcSampleSize(Uri image, int size) throws FileNotFoundException, SecurityException {
-		BitmapFactory.Options options = new BitmapFactory.Options();
-		options.inJustDecodeBounds = true;
-		BitmapFactory.decodeStream(mXmppConnectionService.getContentResolver().openInputStream(image), null, options);
-		return calcSampleSize(options, size);
-	}
-
-	private static int calcSampleSize(File image, int size) {
-		BitmapFactory.Options options = new BitmapFactory.Options();
-		options.inJustDecodeBounds = true;
-		BitmapFactory.decodeFile(image.getAbsolutePath(), options);
-		return calcSampleSize(options, size);
-	}
-
-	public static int calcSampleSize(BitmapFactory.Options options, int size) {
-		int height = options.outHeight;
-		int width = options.outWidth;
-		int inSampleSize = 1;
-
-		if (height > size || width > size) {
-			int halfHeight = height / 2;
-			int halfWidth = width / 2;
-
-			while ((halfHeight / inSampleSize) > size
-					&& (halfWidth / inSampleSize) > size) {
-				inSampleSize *= 2;
-			}
-		}
-		return inSampleSize;
-	}
-
-	public Uri getJingleFileUri(Message message) {
+	public static Uri getJingleFileUri(Message message) {
 		File file = getFile(message);
 		return Uri.parse("file://" + file.getAbsolutePath());
 	}
 
-	public void updateFileParams(Message message) {
-		updateFileParams(message,null);
-	}
-
-	public void updateFileParams(Message message, URL url) {
-		DownloadableFile file = getFile(message);
-		if (message.getType() == Message.TYPE_IMAGE || file.getMimeType().startsWith("image/")) {
-			BitmapFactory.Options options = new BitmapFactory.Options();
-			options.inJustDecodeBounds = true;
-			BitmapFactory.decodeFile(file.getAbsolutePath(), options);
-			int rotation = getRotation(file);
-			boolean rotated = rotation == 90 || rotation == 270;
-			int imageHeight = rotated ? options.outWidth : options.outHeight;
-			int imageWidth = rotated ? options.outHeight : options.outWidth;
-			if (url == null) {
-				message.setBody(Long.toString(file.getSize()) + '|' + imageWidth + '|' + imageHeight);
-			} else {
-				message.setBody(url.toString()+"|"+Long.toString(file.getSize()) + '|' + imageWidth + '|' + imageHeight);
-			}
-		} else {
-			if (url != null) {
-				message.setBody(url.toString()+"|"+Long.toString(file.getSize()));
-			} else {
-				message.setBody(Long.toString(file.getSize()));
-			}
-		}
-
-	}
-
-	public class FileCopyException extends Exception {
-		private static final long serialVersionUID = -1010013599132881427L;
-		private int resId;
-
-		public FileCopyException(int resId) {
-			this.resId = resId;
-		}
-
-		public int getResId() {
-			return resId;
-		}
-	}
-
-	public Bitmap getAvatar(String avatar, int size) {
-		if (avatar == null) {
-			return null;
-		}
-		Bitmap bm = cropCenter(getAvatarUri(avatar), size, size);
-		if (bm == null) {
-			return null;
-		}
-		return bm;
-	}
-
-	public boolean isFileAvailable(Message message) {
+	public static boolean isFileAvailable(Message message) {
 		return getFile(message).exists();
 	}
 
-	public static void close(Closeable stream) {
-		if (stream != null) {
-			try {
-				stream.close();
-			} catch (IOException e) {
-			}
-		}
-	}
-
-	public static void close(Socket socket) {
-		if (socket != null) {
-			try {
-				socket.close();
-			} catch (IOException e) {
-			}
-		}
-	}
-
-
-	public static boolean weOwnFile(Context context, Uri uri) {
-		if (uri == null || !ContentResolver.SCHEME_FILE.equals(uri.getScheme())) {
-			return false;
-		} else if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
-			return fileIsInFilesDir(context, uri);
-		} else {
-			return weOwnFileLollipop(uri);
-		}
-	}
-
-
-	/**
-	 * This is more than hacky but probably way better than doing nothing
-	 * Further 'optimizations' might contain to get the parents of CacheDir and NoBackupDir
-	 * and check against those as well
-	 */
-	private static boolean fileIsInFilesDir(Context context, Uri uri) {
-		try {
-			final String haystack = context.getFilesDir().getParentFile().getCanonicalPath();
-			final String needle = new File(uri.getPath()).getCanonicalPath();
-			return needle.startsWith(haystack);
-		} catch (IOException e) {
-			return false;
-		}
-	}
-
-	@TargetApi(Build.VERSION_CODES.LOLLIPOP)
-	private static boolean weOwnFileLollipop(Uri uri) {
-		try {
-			File file = new File(uri.getPath());
-			FileDescriptor fd = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY).getFileDescriptor();
-			StructStat st = Os.fstat(fd);
-			return st.st_uid == android.os.Process.myUid();
-		} catch (FileNotFoundException e) {
-			return false;
-		} catch (Exception e) {
-			return true;
-		}
+    private FileBackend() {
+        // Static helper class
     }
 }