nextcloud / server

apps/files_trashbin/lib/Trashbin.php

Indentation +937 added lines, -937 removed lines

@@ -47,941 +47,941 @@
 
 class Trashbin {
 
-	// unit: percentage; 50% of available disk space/quota
-	const DEFAULTMAXSIZE = 50;
-
-	/**
-	 * Whether versions have already be rescanned during this PHP request
-	 *
-	 * @var bool
-	 */
-	private static $scannedVersions = false;
-
-	/**
-	 * Ensure we don't need to scan the file during the move to trash
-	 * by triggering the scan in the pre-hook
-	 *
-	 * @param array $params
-	 */
-	public static function ensureFileScannedHook($params) {
-		try {
-			self::getUidAndFilename($params['path']);
-		} catch (NotFoundException $e) {
-			// nothing to scan for non existing files
-		}
-	}
-
-	/**
-	 * get the UID of the owner of the file and the path to the file relative to
-	 * owners files folder
-	 *
-	 * @param string $filename
-	 * @return array
-	 * @throws \OC\User\NoUserException
-	 */
-	public static function getUidAndFilename($filename) {
-		$uid = Filesystem::getOwner($filename);
-		$userManager = \OC::$server->getUserManager();
-		// if the user with the UID doesn't exists, e.g. because the UID points
-		// to a remote user with a federated cloud ID we use the current logged-in
-		// user. We need a valid local user to move the file to the right trash bin
-		if (!$userManager->userExists($uid)) {
-			$uid = User::getUser();
-		}
-		if (!$uid) {
-			// no owner, usually because of share link from ext storage
-			return [null, null];
-		}
-		Filesystem::initMountPoints($uid);
-		if ($uid != User::getUser()) {
-			$info = Filesystem::getFileInfo($filename);
-			$ownerView = new View('/' . $uid . '/files');
-			try {
-				$filename = $ownerView->getPath($info['fileid']);
-			} catch (NotFoundException $e) {
-				$filename = null;
-			}
-		}
-		return [$uid, $filename];
-	}
-
-	/**
-	 * get original location of files for user
-	 *
-	 * @param string $user
-	 * @return array (filename => array (timestamp => original location))
-	 */
-	public static function getLocations($user) {
-		$query = \OC_DB::prepare('SELECT `id`, `timestamp`, `location`'
-			. ' FROM `*PREFIX*files_trash` WHERE `user`=?');
-		$result = $query->execute(array($user));
-		$array = array();
-		while ($row = $result->fetchRow()) {
-			if (isset($array[$row['id']])) {
-				$array[$row['id']][$row['timestamp']] = $row['location'];
-			} else {
-				$array[$row['id']] = array($row['timestamp'] => $row['location']);
-			}
-		}
-		return $array;
-	}
-
-	/**
-	 * get original location of file
-	 *
-	 * @param string $user
-	 * @param string $filename
-	 * @param string $timestamp
-	 * @return string original location
-	 */
-	public static function getLocation($user, $filename, $timestamp) {
-		$query = \OC_DB::prepare('SELECT `location` FROM `*PREFIX*files_trash`'
-			. ' WHERE `user`=? AND `id`=? AND `timestamp`=?');
-		$result = $query->execute(array($user, $filename, $timestamp))->fetchAll();
-		if (isset($result[0]['location'])) {
-			return $result[0]['location'];
-		} else {
-			return false;
-		}
-	}
-
-	private static function setUpTrash($user) {
-		$view = new View('/' . $user);
-		if (!$view->is_dir('files_trashbin')) {
-			$view->mkdir('files_trashbin');
-		}
-		if (!$view->is_dir('files_trashbin/files')) {
-			$view->mkdir('files_trashbin/files');
-		}
-		if (!$view->is_dir('files_trashbin/versions')) {
-			$view->mkdir('files_trashbin/versions');
-		}
-		if (!$view->is_dir('files_trashbin/keys')) {
-			$view->mkdir('files_trashbin/keys');
-		}
-	}
-
-
-	/**
-	 * copy file to owners trash
-	 *
-	 * @param string $sourcePath
-	 * @param string $owner
-	 * @param string $targetPath
-	 * @param $user
-	 * @param integer $timestamp
-	 */
-	private static function copyFilesToUser($sourcePath, $owner, $targetPath, $user, $timestamp) {
-		self::setUpTrash($owner);
-
-		$targetFilename = basename($targetPath);
-		$targetLocation = dirname($targetPath);
-
-		$sourceFilename = basename($sourcePath);
-
-		$view = new View('/');
-
-		$target = $user . '/files_trashbin/files/' . $targetFilename . '.d' . $timestamp;
-		$source = $owner . '/files_trashbin/files/' . $sourceFilename . '.d' . $timestamp;
-		self::copy_recursive($source, $target, $view);
-
-
-		if ($view->file_exists($target)) {
-			$query = \OC_DB::prepare("INSERT INTO `*PREFIX*files_trash` (`id`,`timestamp`,`location`,`user`) VALUES (?,?,?,?)");
-			$result = $query->execute(array($targetFilename, $timestamp, $targetLocation, $user));
-			if (!$result) {
-				\OCP\Util::writeLog('files_trashbin', 'trash bin database couldn\'t be updated for the files owner', \OCP\Util::ERROR);
-			}
-		}
-	}
-
-
-	/**
-	 * move file to the trash bin
-	 *
-	 * @param string $file_path path to the deleted file/directory relative to the files root directory
-	 * @param bool $ownerOnly delete for owner only (if file gets moved out of a shared folder)
-	 *
-	 * @return bool
-	 */
-	public static function move2trash($file_path, $ownerOnly = false) {
-		// get the user for which the filesystem is setup
-		$root = Filesystem::getRoot();
-		list(, $user) = explode('/', $root);
-		list($owner, $ownerPath) = self::getUidAndFilename($file_path);
-
-		// if no owner found (ex: ext storage + share link), will use the current user's trashbin then
-		if (is_null($owner)) {
-			$owner = $user;
-			$ownerPath = $file_path;
-		}
-
-		$ownerView = new View('/' . $owner);
-		// file has been deleted in between
-		if (is_null($ownerPath) || $ownerPath === '' || !$ownerView->file_exists('/files/' . $ownerPath)) {
-			return true;
-		}
-
-		self::setUpTrash($user);
-		if ($owner !== $user) {
-			// also setup for owner
-			self::setUpTrash($owner);
-		}
-
-		$path_parts = pathinfo($ownerPath);
-
-		$filename = $path_parts['basename'];
-		$location = $path_parts['dirname'];
-		$timestamp = time();
-
-		// disable proxy to prevent recursive calls
-		$trashPath = '/files_trashbin/files/' . $filename . '.d' . $timestamp;
-
-		/** @var \OC\Files\Storage\Storage $trashStorage */
-		list($trashStorage, $trashInternalPath) = $ownerView->resolvePath($trashPath);
-		/** @var \OC\Files\Storage\Storage $sourceStorage */
-		list($sourceStorage, $sourceInternalPath) = $ownerView->resolvePath('/files/' . $ownerPath);
-		try {
-			$moveSuccessful = true;
-			if ($trashStorage->file_exists($trashInternalPath)) {
-				$trashStorage->unlink($trashInternalPath);
-			}
-			$trashStorage->moveFromStorage($sourceStorage, $sourceInternalPath, $trashInternalPath);
-		} catch (\OCA\Files_Trashbin\Exceptions\CopyRecursiveException $e) {
-			$moveSuccessful = false;
-			if ($trashStorage->file_exists($trashInternalPath)) {
-				$trashStorage->unlink($trashInternalPath);
-			}
-			\OCP\Util::writeLog('files_trashbin', 'Couldn\'t move ' . $file_path . ' to the trash bin', \OCP\Util::ERROR);
-		}
-
-		if ($sourceStorage->file_exists($sourceInternalPath)) { // failed to delete the original file, abort
-			if ($sourceStorage->is_dir($sourceInternalPath)) {
-				$sourceStorage->rmdir($sourceInternalPath);
-			} else {
-				$sourceStorage->unlink($sourceInternalPath);
-			}
-			return false;
-		}
-
-		$trashStorage->getUpdater()->renameFromStorage($sourceStorage, $sourceInternalPath, $trashInternalPath);
-
-		if ($moveSuccessful) {
-			$query = \OC_DB::prepare("INSERT INTO `*PREFIX*files_trash` (`id`,`timestamp`,`location`,`user`) VALUES (?,?,?,?)");
-			$result = $query->execute(array($filename, $timestamp, $location, $owner));
-			if (!$result) {
-				\OCP\Util::writeLog('files_trashbin', 'trash bin database couldn\'t be updated', \OCP\Util::ERROR);
-			}
-			\OCP\Util::emitHook('\OCA\Files_Trashbin\Trashbin', 'post_moveToTrash', array('filePath' => Filesystem::normalizePath($file_path),
-				'trashPath' => Filesystem::normalizePath($filename . '.d' . $timestamp)));
-
-			self::retainVersions($filename, $owner, $ownerPath, $timestamp);
-
-			// if owner !== user we need to also add a copy to the users trash
-			if ($user !== $owner && $ownerOnly === false) {
-				self::copyFilesToUser($ownerPath, $owner, $file_path, $user, $timestamp);
-			}
-		}
-
-		self::scheduleExpire($user);
-
-		// if owner !== user we also need to update the owners trash size
-		if ($owner !== $user) {
-			self::scheduleExpire($owner);
-		}
-
-		return $moveSuccessful;
-	}
-
-	/**
-	 * Move file versions to trash so that they can be restored later
-	 *
-	 * @param string $filename of deleted file
-	 * @param string $owner owner user id
-	 * @param string $ownerPath path relative to the owner's home storage
-	 * @param integer $timestamp when the file was deleted
-	 */
-	private static function retainVersions($filename, $owner, $ownerPath, $timestamp) {
-		if (\OCP\App::isEnabled('files_versions') && !empty($ownerPath)) {
-
-			$user = User::getUser();
-			$rootView = new View('/');
-
-			if ($rootView->is_dir($owner . '/files_versions/' . $ownerPath)) {
-				if ($owner !== $user) {
-					self::copy_recursive($owner . '/files_versions/' . $ownerPath, $owner . '/files_trashbin/versions/' . basename($ownerPath) . '.d' . $timestamp, $rootView);
-				}
-				self::move($rootView, $owner . '/files_versions/' . $ownerPath, $user . '/files_trashbin/versions/' . $filename . '.d' . $timestamp);
-			} else if ($versions = \OCA\Files_Versions\Storage::getVersions($owner, $ownerPath)) {
-
-				foreach ($versions as $v) {
-					if ($owner !== $user) {
-						self::copy($rootView, $owner . '/files_versions' . $v['path'] . '.v' . $v['version'], $owner . '/files_trashbin/versions/' . $v['name'] . '.v' . $v['version'] . '.d' . $timestamp);
-					}
-					self::move($rootView, $owner . '/files_versions' . $v['path'] . '.v' . $v['version'], $user . '/files_trashbin/versions/' . $filename . '.v' . $v['version'] . '.d' . $timestamp);
-				}
-			}
-		}
-	}
-
-	/**
-	 * Move a file or folder on storage level
-	 *
-	 * @param View $view
-	 * @param string $source
-	 * @param string $target
-	 * @return bool
-	 */
-	private static function move(View $view, $source, $target) {
-		/** @var \OC\Files\Storage\Storage $sourceStorage */
-		list($sourceStorage, $sourceInternalPath) = $view->resolvePath($source);
-		/** @var \OC\Files\Storage\Storage $targetStorage */
-		list($targetStorage, $targetInternalPath) = $view->resolvePath($target);
-		/** @var \OC\Files\Storage\Storage $ownerTrashStorage */
-
-		$result = $targetStorage->moveFromStorage($sourceStorage, $sourceInternalPath, $targetInternalPath);
-		if ($result) {
-			$targetStorage->getUpdater()->renameFromStorage($sourceStorage, $sourceInternalPath, $targetInternalPath);
-		}
-		return $result;
-	}
-
-	/**
-	 * Copy a file or folder on storage level
-	 *
-	 * @param View $view
-	 * @param string $source
-	 * @param string $target
-	 * @return bool
-	 */
-	private static function copy(View $view, $source, $target) {
-		/** @var \OC\Files\Storage\Storage $sourceStorage */
-		list($sourceStorage, $sourceInternalPath) = $view->resolvePath($source);
-		/** @var \OC\Files\Storage\Storage $targetStorage */
-		list($targetStorage, $targetInternalPath) = $view->resolvePath($target);
-		/** @var \OC\Files\Storage\Storage $ownerTrashStorage */
-
-		$result = $targetStorage->copyFromStorage($sourceStorage, $sourceInternalPath, $targetInternalPath);
-		if ($result) {
-			$targetStorage->getUpdater()->update($targetInternalPath);
-		}
-		return $result;
-	}
-
-	/**
-	 * Restore a file or folder from trash bin
-	 *
-	 * @param string $file path to the deleted file/folder relative to "files_trashbin/files/",
-	 * including the timestamp suffix ".d12345678"
-	 * @param string $filename name of the file/folder
-	 * @param int $timestamp time when the file/folder was deleted
-	 *
-	 * @return bool true on success, false otherwise
-	 */
-	public static function restore($file, $filename, $timestamp) {
-		$user = User::getUser();
-		$view = new View('/' . $user);
-
-		$location = '';
-		if ($timestamp) {
-			$location = self::getLocation($user, $filename, $timestamp);
-			if ($location === false) {
-				\OCP\Util::writeLog('files_trashbin', 'trash bin database inconsistent!', \OCP\Util::ERROR);
-			} else {
-				// if location no longer exists, restore file in the root directory
-				if ($location !== '/' &&
-					(!$view->is_dir('files/' . $location) ||
-						!$view->isCreatable('files/' . $location))
-				) {
-					$location = '';
-				}
-			}
-		}
-
-		// we need a  extension in case a file/dir with the same name already exists
-		$uniqueFilename = self::getUniqueFilename($location, $filename, $view);
-
-		$source = Filesystem::normalizePath('files_trashbin/files/' . $file);
-		$target = Filesystem::normalizePath('files/' . $location . '/' . $uniqueFilename);
-		if (!$view->file_exists($source)) {
-			return false;
-		}
-		$mtime = $view->filemtime($source);
-
-		// restore file
-		$restoreResult = $view->rename($source, $target);
-
-		// handle the restore result
-		if ($restoreResult) {
-			$fakeRoot = $view->getRoot();
-			$view->chroot('/' . $user . '/files');
-			$view->touch('/' . $location . '/' . $uniqueFilename, $mtime);
-			$view->chroot($fakeRoot);
-			\OCP\Util::emitHook('\OCA\Files_Trashbin\Trashbin', 'post_restore', array('filePath' => Filesystem::normalizePath('/' . $location . '/' . $uniqueFilename),
-				'trashPath' => Filesystem::normalizePath($file)));
-
-			self::restoreVersions($view, $file, $filename, $uniqueFilename, $location, $timestamp);
-
-			if ($timestamp) {
-				$query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_trash` WHERE `user`=? AND `id`=? AND `timestamp`=?');
-				$query->execute(array($user, $filename, $timestamp));
-			}
-
-			return true;
-		}
-
-		return false;
-	}
-
-	/**
-	 * restore versions from trash bin
-	 *
-	 * @param View $view file view
-	 * @param string $file complete path to file
-	 * @param string $filename name of file once it was deleted
-	 * @param string $uniqueFilename new file name to restore the file without overwriting existing files
-	 * @param string $location location if file
-	 * @param int $timestamp deletion time
-	 * @return false|null
-	 */
-	private static function restoreVersions(View $view, $file, $filename, $uniqueFilename, $location, $timestamp) {
-
-		if (\OCP\App::isEnabled('files_versions')) {
-
-			$user = User::getUser();
-			$rootView = new View('/');
-
-			$target = Filesystem::normalizePath('/' . $location . '/' . $uniqueFilename);
-
-			list($owner, $ownerPath) = self::getUidAndFilename($target);
-
-			// file has been deleted in between
-			if (empty($ownerPath)) {
-				return false;
-			}
-
-			if ($timestamp) {
-				$versionedFile = $filename;
-			} else {
-				$versionedFile = $file;
-			}
-
-			if ($view->is_dir('/files_trashbin/versions/' . $file)) {
-				$rootView->rename(Filesystem::normalizePath($user . '/files_trashbin/versions/' . $file), Filesystem::normalizePath($owner . '/files_versions/' . $ownerPath));
-			} else if ($versions = self::getVersionsFromTrash($versionedFile, $timestamp, $user)) {
-				foreach ($versions as $v) {
-					if ($timestamp) {
-						$rootView->rename($user . '/files_trashbin/versions/' . $versionedFile . '.v' . $v . '.d' . $timestamp, $owner . '/files_versions/' . $ownerPath . '.v' . $v);
-					} else {
-						$rootView->rename($user . '/files_trashbin/versions/' . $versionedFile . '.v' . $v, $owner . '/files_versions/' . $ownerPath . '.v' . $v);
-					}
-				}
-			}
-		}
-	}
-
-	/**
-	 * delete all files from the trash
-	 */
-	public static function deleteAll() {
-		$user = User::getUser();
-		$view = new View('/' . $user);
-		$fileInfos = $view->getDirectoryContent('files_trashbin/files');
-
-		// Array to store the relative path in (after the file is deleted, the view won't be able to relativise the path anymore)
-		$filePaths = array();
-		foreach($fileInfos as $fileInfo){
-			$filePaths[] = $view->getRelativePath($fileInfo->getPath());
-		}
-		unset($fileInfos); // save memory
-
-		// Bulk PreDelete-Hook
-		\OC_Hook::emit('\OCP\Trashbin', 'preDeleteAll', array('paths' => $filePaths));
-
-		// Single-File Hooks
-		foreach($filePaths as $path){
-			self::emitTrashbinPreDelete($path);
-		}
-
-		// actual file deletion
-		$view->deleteAll('files_trashbin');
-		$query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_trash` WHERE `user`=?');
-		$query->execute(array($user));
-
-		// Bulk PostDelete-Hook
-		\OC_Hook::emit('\OCP\Trashbin', 'deleteAll', array('paths' => $filePaths));
-
-		// Single-File Hooks
-		foreach($filePaths as $path){
-			self::emitTrashbinPostDelete($path);
-		}
-
-		$view->mkdir('files_trashbin');
-		$view->mkdir('files_trashbin/files');
-
-		return true;
-	}
-
-	/**
-	 * wrapper function to emit the 'preDelete' hook of \OCP\Trashbin before a file is deleted
-	 * @param string $path
-	 */
-	protected static function emitTrashbinPreDelete($path){
-		\OC_Hook::emit('\OCP\Trashbin', 'preDelete', array('path' => $path));
-	}
-
-	/**
-	 * wrapper function to emit the 'delete' hook of \OCP\Trashbin after a file has been deleted
-	 * @param string $path
-	 */
-	protected static function emitTrashbinPostDelete($path){
-		\OC_Hook::emit('\OCP\Trashbin', 'delete', array('path' => $path));
-	}
-
-	/**
-	 * delete file from trash bin permanently
-	 *
-	 * @param string $filename path to the file
-	 * @param string $user
-	 * @param int $timestamp of deletion time
-	 *
-	 * @return int size of deleted files
-	 */
-	public static function delete($filename, $user, $timestamp = null) {
-		$view = new View('/' . $user);
-		$size = 0;
-
-		if ($timestamp) {
-			$query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_trash` WHERE `user`=? AND `id`=? AND `timestamp`=?');
-			$query->execute(array($user, $filename, $timestamp));
-			$file = $filename . '.d' . $timestamp;
-		} else {
-			$file = $filename;
-		}
-
-		$size += self::deleteVersions($view, $file, $filename, $timestamp, $user);
-
-		if ($view->is_dir('/files_trashbin/files/' . $file)) {
-			$size += self::calculateSize(new View('/' . $user . '/files_trashbin/files/' . $file));
-		} else {
-			$size += $view->filesize('/files_trashbin/files/' . $file);
-		}
-		self::emitTrashbinPreDelete('/files_trashbin/files/' . $file);
-		$view->unlink('/files_trashbin/files/' . $file);
-		self::emitTrashbinPostDelete('/files_trashbin/files/' . $file);
-
-		return $size;
-	}
-
-	/**
-	 * @param View $view
-	 * @param string $file
-	 * @param string $filename
-	 * @param integer|null $timestamp
-	 * @param string $user
-	 * @return int
-	 */
-	private static function deleteVersions(View $view, $file, $filename, $timestamp, $user) {
-		$size = 0;
-		if (\OCP\App::isEnabled('files_versions')) {
-			if ($view->is_dir('files_trashbin/versions/' . $file)) {
-				$size += self::calculateSize(new View('/' . $user . '/files_trashbin/versions/' . $file));
-				$view->unlink('files_trashbin/versions/' . $file);
-			} else if ($versions = self::getVersionsFromTrash($filename, $timestamp, $user)) {
-				foreach ($versions as $v) {
-					if ($timestamp) {
-						$size += $view->filesize('/files_trashbin/versions/' . $filename . '.v' . $v . '.d' . $timestamp);
-						$view->unlink('/files_trashbin/versions/' . $filename . '.v' . $v . '.d' . $timestamp);
-					} else {
-						$size += $view->filesize('/files_trashbin/versions/' . $filename . '.v' . $v);
-						$view->unlink('/files_trashbin/versions/' . $filename . '.v' . $v);
-					}
-				}
-			}
-		}
-		return $size;
-	}
-
-	/**
-	 * check to see whether a file exists in trashbin
-	 *
-	 * @param string $filename path to the file
-	 * @param int $timestamp of deletion time
-	 * @return bool true if file exists, otherwise false
-	 */
-	public static function file_exists($filename, $timestamp = null) {
-		$user = User::getUser();
-		$view = new View('/' . $user);
-
-		if ($timestamp) {
-			$filename = $filename . '.d' . $timestamp;
-		} else {
-			$filename = $filename;
-		}
-
-		$target = Filesystem::normalizePath('files_trashbin/files/' . $filename);
-		return $view->file_exists($target);
-	}
-
-	/**
-	 * deletes used space for trash bin in db if user was deleted
-	 *
-	 * @param string $uid id of deleted user
-	 * @return bool result of db delete operation
-	 */
-	public static function deleteUser($uid) {
-		$query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_trash` WHERE `user`=?');
-		return $query->execute(array($uid));
-	}
-
-	/**
-	 * calculate remaining free space for trash bin
-	 *
-	 * @param integer $trashbinSize current size of the trash bin
-	 * @param string $user
-	 * @return int available free space for trash bin
-	 */
-	private static function calculateFreeSpace($trashbinSize, $user) {
-		$softQuota = true;
-		$userObject = \OC::$server->getUserManager()->get($user);
-		if(is_null($userObject)) {
-			return 0;
-		}
-		$quota = $userObject->getQuota();
-		if ($quota === null || $quota === 'none') {
-			$quota = Filesystem::free_space('/');
-			$softQuota = false;
-			// inf or unknown free space
-			if ($quota < 0) {
-				$quota = PHP_INT_MAX;
-			}
-		} else {
-			$quota = \OCP\Util::computerFileSize($quota);
-		}
-
-		// calculate available space for trash bin
-		// subtract size of files and current trash bin size from quota
-		if ($softQuota) {
-			$userFolder = \OC::$server->getUserFolder($user);
-			if(is_null($userFolder)) {
-				return 0;
-			}
-			$free = $quota - $userFolder->getSize(); // remaining free space for user
-			if ($free > 0) {
-				$availableSpace = ($free * self::DEFAULTMAXSIZE / 100) - $trashbinSize; // how much space can be used for versions
-			} else {
-				$availableSpace = $free - $trashbinSize;
-			}
-		} else {
-			$availableSpace = $quota;
-		}
-
-		return $availableSpace;
-	}
-
-	/**
-	 * resize trash bin if necessary after a new file was added to ownCloud
-	 *
-	 * @param string $user user id
-	 */
-	public static function resizeTrash($user) {
-
-		$size = self::getTrashbinSize($user);
-
-		$freeSpace = self::calculateFreeSpace($size, $user);
-
-		if ($freeSpace < 0) {
-			self::scheduleExpire($user);
-		}
-	}
-
-	/**
-	 * clean up the trash bin
-	 *
-	 * @param string $user
-	 */
-	public static function expire($user) {
-		$trashBinSize = self::getTrashbinSize($user);
-		$availableSpace = self::calculateFreeSpace($trashBinSize, $user);
-
-		$dirContent = Helper::getTrashFiles('/', $user, 'mtime');
-
-		// delete all files older then $retention_obligation
-		list($delSize, $count) = self::deleteExpiredFiles($dirContent, $user);
-
-		$availableSpace += $delSize;
-
-		// delete files from trash until we meet the trash bin size limit again
-		self::deleteFiles(array_slice($dirContent, $count), $user, $availableSpace);
-	}
-
-	/**
-	 * @param string $user
-	 */
-	private static function scheduleExpire($user) {
-		// let the admin disable auto expire
-		$application = new Application();
-		$expiration = $application->getContainer()->query('Expiration');
-		if ($expiration->isEnabled()) {
-			\OC::$server->getCommandBus()->push(new Expire($user));
-		}
-	}
-
-	/**
-	 * if the size limit for the trash bin is reached, we delete the oldest
-	 * files in the trash bin until we meet the limit again
-	 *
-	 * @param array $files
-	 * @param string $user
-	 * @param int $availableSpace available disc space
-	 * @return int size of deleted files
-	 */
-	protected static function deleteFiles($files, $user, $availableSpace) {
-		$application = new Application();
-		$expiration = $application->getContainer()->query('Expiration');
-		$size = 0;
-
-		if ($availableSpace < 0) {
-			foreach ($files as $file) {
-				if ($availableSpace < 0 && $expiration->isExpired($file['mtime'], true)) {
-					$tmp = self::delete($file['name'], $user, $file['mtime']);
-					\OCP\Util::writeLog('files_trashbin', 'remove "' . $file['name'] . '" (' . $tmp . 'B) to meet the limit of trash bin size (50% of available quota)', \OCP\Util::INFO);
-					$availableSpace += $tmp;
-					$size += $tmp;
-				} else {
-					break;
-				}
-			}
-		}
-		return $size;
-	}
-
-	/**
-	 * delete files older then max storage time
-	 *
-	 * @param array $files list of files sorted by mtime
-	 * @param string $user
-	 * @return integer[] size of deleted files and number of deleted files
-	 */
-	public static function deleteExpiredFiles($files, $user) {
-		$application = new Application();
-		$expiration = $application->getContainer()->query('Expiration');
-		$size = 0;
-		$count = 0;
-		foreach ($files as $file) {
-			$timestamp = $file['mtime'];
-			$filename = $file['name'];
-			if ($expiration->isExpired($timestamp)) {
-				$count++;
-				$size += self::delete($filename, $user, $timestamp);
-				\OC::$server->getLogger()->info(
-					'Remove "' . $filename . '" from trashbin because it exceeds max retention obligation term.',
-					['app' => 'files_trashbin']
-				);
-			} else {
-				break;
-			}
-		}
-
-		return array($size, $count);
-	}
-
-	/**
-	 * recursive copy to copy a whole directory
-	 *
-	 * @param string $source source path, relative to the users files directory
-	 * @param string $destination destination path relative to the users root directoy
-	 * @param View $view file view for the users root directory
-	 * @return int
-	 * @throws Exceptions\CopyRecursiveException
-	 */
-	private static function copy_recursive($source, $destination, View $view) {
-		$size = 0;
-		if ($view->is_dir($source)) {
-			$view->mkdir($destination);
-			$view->touch($destination, $view->filemtime($source));
-			foreach ($view->getDirectoryContent($source) as $i) {
-				$pathDir = $source . '/' . $i['name'];
-				if ($view->is_dir($pathDir)) {
-					$size += self::copy_recursive($pathDir, $destination . '/' . $i['name'], $view);
-				} else {
-					$size += $view->filesize($pathDir);
-					$result = $view->copy($pathDir, $destination . '/' . $i['name']);
-					if (!$result) {
-						throw new \OCA\Files_Trashbin\Exceptions\CopyRecursiveException();
-					}
-					$view->touch($destination . '/' . $i['name'], $view->filemtime($pathDir));
-				}
-			}
-		} else {
-			$size += $view->filesize($source);
-			$result = $view->copy($source, $destination);
-			if (!$result) {
-				throw new \OCA\Files_Trashbin\Exceptions\CopyRecursiveException();
-			}
-			$view->touch($destination, $view->filemtime($source));
-		}
-		return $size;
-	}
-
-	/**
-	 * find all versions which belong to the file we want to restore
-	 *
-	 * @param string $filename name of the file which should be restored
-	 * @param int $timestamp timestamp when the file was deleted
-	 * @return array
-	 */
-	private static function getVersionsFromTrash($filename, $timestamp, $user) {
-		$view = new View('/' . $user . '/files_trashbin/versions');
-		$versions = array();
-
-		//force rescan of versions, local storage may not have updated the cache
-		if (!self::$scannedVersions) {
-			/** @var \OC\Files\Storage\Storage $storage */
-			list($storage,) = $view->resolvePath('/');
-			$storage->getScanner()->scan('files_trashbin/versions');
-			self::$scannedVersions = true;
-		}
-
-		if ($timestamp) {
-			// fetch for old versions
-			$matches = $view->searchRaw($filename . '.v%.d' . $timestamp);
-			$offset = -strlen($timestamp) - 2;
-		} else {
-			$matches = $view->searchRaw($filename . '.v%');
-		}
-
-		if (is_array($matches)) {
-			foreach ($matches as $ma) {
-				if ($timestamp) {
-					$parts = explode('.v', substr($ma['path'], 0, $offset));
-					$versions[] = (end($parts));
-				} else {
-					$parts = explode('.v', $ma);
-					$versions[] = (end($parts));
-				}
-			}
-		}
-		return $versions;
-	}
-
-	/**
-	 * find unique extension for restored file if a file with the same name already exists
-	 *
-	 * @param string $location where the file should be restored
-	 * @param string $filename name of the file
-	 * @param View $view filesystem view relative to users root directory
-	 * @return string with unique extension
-	 */
-	private static function getUniqueFilename($location, $filename, View $view) {
-		$ext = pathinfo($filename, PATHINFO_EXTENSION);
-		$name = pathinfo($filename, PATHINFO_FILENAME);
-		$l = \OC::$server->getL10N('files_trashbin');
-
-		$location = '/' . trim($location, '/');
-
-		// if extension is not empty we set a dot in front of it
-		if ($ext !== '') {
-			$ext = '.' . $ext;
-		}
-
-		if ($view->file_exists('files' . $location . '/' . $filename)) {
-			$i = 2;
-			$uniqueName = $name . " (" . $l->t("restored") . ")" . $ext;
-			while ($view->file_exists('files' . $location . '/' . $uniqueName)) {
-				$uniqueName = $name . " (" . $l->t("restored") . " " . $i . ")" . $ext;
-				$i++;
-			}
-
-			return $uniqueName;
-		}
-
-		return $filename;
-	}
-
-	/**
-	 * get the size from a given root folder
-	 *
-	 * @param View $view file view on the root folder
-	 * @return integer size of the folder
-	 */
-	private static function calculateSize($view) {
-		$root = \OC::$server->getConfig()->getSystemValue('datadirectory', \OC::$SERVERROOT . '/data') . $view->getAbsolutePath('');
-		if (!file_exists($root)) {
-			return 0;
-		}
-		$iterator = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($root), \RecursiveIteratorIterator::CHILD_FIRST);
-		$size = 0;
-
-		/**
-		 * RecursiveDirectoryIterator on an NFS path isn't iterable with foreach
-		 * This bug is fixed in PHP 5.5.9 or before
-		 * See #8376
-		 */
-		$iterator->rewind();
-		while ($iterator->valid()) {
-			$path = $iterator->current();
-			$relpath = substr($path, strlen($root) - 1);
-			if (!$view->is_dir($relpath)) {
-				$size += $view->filesize($relpath);
-			}
-			$iterator->next();
-		}
-		return $size;
-	}
-
-	/**
-	 * get current size of trash bin from a given user
-	 *
-	 * @param string $user user who owns the trash bin
-	 * @return integer trash bin size
-	 */
-	private static function getTrashbinSize($user) {
-		$view = new View('/' . $user);
-		$fileInfo = $view->getFileInfo('/files_trashbin');
-		return isset($fileInfo['size']) ? $fileInfo['size'] : 0;
-	}
-
-	/**
-	 * register hooks
-	 */
-	public static function registerHooks() {
-		// create storage wrapper on setup
-		\OCP\Util::connectHook('OC_Filesystem', 'preSetup', 'OCA\Files_Trashbin\Storage', 'setupStorage');
-		//Listen to delete user signal
-		\OCP\Util::connectHook('OC_User', 'pre_deleteUser', 'OCA\Files_Trashbin\Hooks', 'deleteUser_hook');
-		//Listen to post write hook
-		\OCP\Util::connectHook('OC_Filesystem', 'post_write', 'OCA\Files_Trashbin\Hooks', 'post_write_hook');
-		// pre and post-rename, disable trash logic for the copy+unlink case
-		\OCP\Util::connectHook('OC_Filesystem', 'delete', 'OCA\Files_Trashbin\Trashbin', 'ensureFileScannedHook');
-		\OCP\Util::connectHook('OC_Filesystem', 'rename', 'OCA\Files_Trashbin\Storage', 'preRenameHook');
-		\OCP\Util::connectHook('OC_Filesystem', 'post_rename', 'OCA\Files_Trashbin\Storage', 'postRenameHook');
-	}
-
-	/**
-	 * check if trash bin is empty for a given user
-	 *
-	 * @param string $user
-	 * @return bool
-	 */
-	public static function isEmpty($user) {
-
-		$view = new View('/' . $user . '/files_trashbin');
-		if ($view->is_dir('/files') && $dh = $view->opendir('/files')) {
-			while ($file = readdir($dh)) {
-				if (!Filesystem::isIgnoredDir($file)) {
-					return false;
-				}
-			}
-		}
-		return true;
-	}
-
-	/**
-	 * @param $path
-	 * @return string
-	 */
-	public static function preview_icon($path) {
-		return \OCP\Util::linkToRoute('core_ajax_trashbin_preview', array('x' => 32, 'y' => 32, 'file' => $path));
-	}
+    // unit: percentage; 50% of available disk space/quota
+    const DEFAULTMAXSIZE = 50;
+
+    /**
+     * Whether versions have already be rescanned during this PHP request
+     *
+     * @var bool
+     */
+    private static $scannedVersions = false;
+
+    /**
+     * Ensure we don't need to scan the file during the move to trash
+     * by triggering the scan in the pre-hook
+     *
+     * @param array $params
+     */
+    public static function ensureFileScannedHook($params) {
+        try {
+            self::getUidAndFilename($params['path']);
+        } catch (NotFoundException $e) {
+            // nothing to scan for non existing files
+        }
+    }
+
+    /**
+     * get the UID of the owner of the file and the path to the file relative to
+     * owners files folder
+     *
+     * @param string $filename
+     * @return array
+     * @throws \OC\User\NoUserException
+     */
+    public static function getUidAndFilename($filename) {
+        $uid = Filesystem::getOwner($filename);
+        $userManager = \OC::$server->getUserManager();
+        // if the user with the UID doesn't exists, e.g. because the UID points
+        // to a remote user with a federated cloud ID we use the current logged-in
+        // user. We need a valid local user to move the file to the right trash bin
+        if (!$userManager->userExists($uid)) {
+            $uid = User::getUser();
+        }
+        if (!$uid) {
+            // no owner, usually because of share link from ext storage
+            return [null, null];
+        }
+        Filesystem::initMountPoints($uid);
+        if ($uid != User::getUser()) {
+            $info = Filesystem::getFileInfo($filename);
+            $ownerView = new View('/' . $uid . '/files');
+            try {
+                $filename = $ownerView->getPath($info['fileid']);
+            } catch (NotFoundException $e) {
+                $filename = null;
+            }
+        }
+        return [$uid, $filename];
+    }
+
+    /**
+     * get original location of files for user
+     *
+     * @param string $user
+     * @return array (filename => array (timestamp => original location))
+     */
+    public static function getLocations($user) {
+        $query = \OC_DB::prepare('SELECT `id`, `timestamp`, `location`'
+            . ' FROM `*PREFIX*files_trash` WHERE `user`=?');
+        $result = $query->execute(array($user));
+        $array = array();
+        while ($row = $result->fetchRow()) {
+            if (isset($array[$row['id']])) {
+                $array[$row['id']][$row['timestamp']] = $row['location'];
+            } else {
+                $array[$row['id']] = array($row['timestamp'] => $row['location']);
+            }
+        }
+        return $array;
+    }
+
+    /**
+     * get original location of file
+     *
+     * @param string $user
+     * @param string $filename
+     * @param string $timestamp
+     * @return string original location
+     */
+    public static function getLocation($user, $filename, $timestamp) {
+        $query = \OC_DB::prepare('SELECT `location` FROM `*PREFIX*files_trash`'
+            . ' WHERE `user`=? AND `id`=? AND `timestamp`=?');
+        $result = $query->execute(array($user, $filename, $timestamp))->fetchAll();
+        if (isset($result[0]['location'])) {
+            return $result[0]['location'];
+        } else {
+            return false;
+        }
+    }
+
+    private static function setUpTrash($user) {
+        $view = new View('/' . $user);
+        if (!$view->is_dir('files_trashbin')) {
+            $view->mkdir('files_trashbin');
+        }
+        if (!$view->is_dir('files_trashbin/files')) {
+            $view->mkdir('files_trashbin/files');
+        }
+        if (!$view->is_dir('files_trashbin/versions')) {
+            $view->mkdir('files_trashbin/versions');
+        }
+        if (!$view->is_dir('files_trashbin/keys')) {
+            $view->mkdir('files_trashbin/keys');
+        }
+    }
+
+
+    /**
+     * copy file to owners trash
+     *
+     * @param string $sourcePath
+     * @param string $owner
+     * @param string $targetPath
+     * @param $user
+     * @param integer $timestamp
+     */
+    private static function copyFilesToUser($sourcePath, $owner, $targetPath, $user, $timestamp) {
+        self::setUpTrash($owner);
+
+        $targetFilename = basename($targetPath);
+        $targetLocation = dirname($targetPath);
+
+        $sourceFilename = basename($sourcePath);
+
+        $view = new View('/');
+
+        $target = $user . '/files_trashbin/files/' . $targetFilename . '.d' . $timestamp;
+        $source = $owner . '/files_trashbin/files/' . $sourceFilename . '.d' . $timestamp;
+        self::copy_recursive($source, $target, $view);
+
+
+        if ($view->file_exists($target)) {
+            $query = \OC_DB::prepare("INSERT INTO `*PREFIX*files_trash` (`id`,`timestamp`,`location`,`user`) VALUES (?,?,?,?)");
+            $result = $query->execute(array($targetFilename, $timestamp, $targetLocation, $user));
+            if (!$result) {
+                \OCP\Util::writeLog('files_trashbin', 'trash bin database couldn\'t be updated for the files owner', \OCP\Util::ERROR);
+            }
+        }
+    }
+
+
+    /**
+     * move file to the trash bin
+     *
+     * @param string $file_path path to the deleted file/directory relative to the files root directory
+     * @param bool $ownerOnly delete for owner only (if file gets moved out of a shared folder)
+     *
+     * @return bool
+     */
+    public static function move2trash($file_path, $ownerOnly = false) {
+        // get the user for which the filesystem is setup
+        $root = Filesystem::getRoot();
+        list(, $user) = explode('/', $root);
+        list($owner, $ownerPath) = self::getUidAndFilename($file_path);
+
+        // if no owner found (ex: ext storage + share link), will use the current user's trashbin then
+        if (is_null($owner)) {
+            $owner = $user;
+            $ownerPath = $file_path;
+        }
+
+        $ownerView = new View('/' . $owner);
+        // file has been deleted in between
+        if (is_null($ownerPath) || $ownerPath === '' || !$ownerView->file_exists('/files/' . $ownerPath)) {
+            return true;
+        }
+
+        self::setUpTrash($user);
+        if ($owner !== $user) {
+            // also setup for owner
+            self::setUpTrash($owner);
+        }
+
+        $path_parts = pathinfo($ownerPath);
+
+        $filename = $path_parts['basename'];
+        $location = $path_parts['dirname'];
+        $timestamp = time();
+
+        // disable proxy to prevent recursive calls
+        $trashPath = '/files_trashbin/files/' . $filename . '.d' . $timestamp;
+
+        /** @var \OC\Files\Storage\Storage $trashStorage */
+        list($trashStorage, $trashInternalPath) = $ownerView->resolvePath($trashPath);
+        /** @var \OC\Files\Storage\Storage $sourceStorage */
+        list($sourceStorage, $sourceInternalPath) = $ownerView->resolvePath('/files/' . $ownerPath);
+        try {
+            $moveSuccessful = true;
+            if ($trashStorage->file_exists($trashInternalPath)) {
+                $trashStorage->unlink($trashInternalPath);
+            }
+            $trashStorage->moveFromStorage($sourceStorage, $sourceInternalPath, $trashInternalPath);
+        } catch (\OCA\Files_Trashbin\Exceptions\CopyRecursiveException $e) {
+            $moveSuccessful = false;
+            if ($trashStorage->file_exists($trashInternalPath)) {
+                $trashStorage->unlink($trashInternalPath);
+            }
+            \OCP\Util::writeLog('files_trashbin', 'Couldn\'t move ' . $file_path . ' to the trash bin', \OCP\Util::ERROR);
+        }
+
+        if ($sourceStorage->file_exists($sourceInternalPath)) { // failed to delete the original file, abort
+            if ($sourceStorage->is_dir($sourceInternalPath)) {
+                $sourceStorage->rmdir($sourceInternalPath);
+            } else {
+                $sourceStorage->unlink($sourceInternalPath);
+            }
+            return false;
+        }
+
+        $trashStorage->getUpdater()->renameFromStorage($sourceStorage, $sourceInternalPath, $trashInternalPath);
+
+        if ($moveSuccessful) {
+            $query = \OC_DB::prepare("INSERT INTO `*PREFIX*files_trash` (`id`,`timestamp`,`location`,`user`) VALUES (?,?,?,?)");
+            $result = $query->execute(array($filename, $timestamp, $location, $owner));
+            if (!$result) {
+                \OCP\Util::writeLog('files_trashbin', 'trash bin database couldn\'t be updated', \OCP\Util::ERROR);
+            }
+            \OCP\Util::emitHook('\OCA\Files_Trashbin\Trashbin', 'post_moveToTrash', array('filePath' => Filesystem::normalizePath($file_path),
+                'trashPath' => Filesystem::normalizePath($filename . '.d' . $timestamp)));
+
+            self::retainVersions($filename, $owner, $ownerPath, $timestamp);
+
+            // if owner !== user we need to also add a copy to the users trash
+            if ($user !== $owner && $ownerOnly === false) {
+                self::copyFilesToUser($ownerPath, $owner, $file_path, $user, $timestamp);
+            }
+        }
+
+        self::scheduleExpire($user);
+
+        // if owner !== user we also need to update the owners trash size
+        if ($owner !== $user) {
+            self::scheduleExpire($owner);
+        }
+
+        return $moveSuccessful;
+    }
+
+    /**
+     * Move file versions to trash so that they can be restored later
+     *
+     * @param string $filename of deleted file
+     * @param string $owner owner user id
+     * @param string $ownerPath path relative to the owner's home storage
+     * @param integer $timestamp when the file was deleted
+     */
+    private static function retainVersions($filename, $owner, $ownerPath, $timestamp) {
+        if (\OCP\App::isEnabled('files_versions') && !empty($ownerPath)) {
+
+            $user = User::getUser();
+            $rootView = new View('/');
+
+            if ($rootView->is_dir($owner . '/files_versions/' . $ownerPath)) {
+                if ($owner !== $user) {
+                    self::copy_recursive($owner . '/files_versions/' . $ownerPath, $owner . '/files_trashbin/versions/' . basename($ownerPath) . '.d' . $timestamp, $rootView);
+                }
+                self::move($rootView, $owner . '/files_versions/' . $ownerPath, $user . '/files_trashbin/versions/' . $filename . '.d' . $timestamp);
+            } else if ($versions = \OCA\Files_Versions\Storage::getVersions($owner, $ownerPath)) {
+
+                foreach ($versions as $v) {
+                    if ($owner !== $user) {
+                        self::copy($rootView, $owner . '/files_versions' . $v['path'] . '.v' . $v['version'], $owner . '/files_trashbin/versions/' . $v['name'] . '.v' . $v['version'] . '.d' . $timestamp);
+                    }
+                    self::move($rootView, $owner . '/files_versions' . $v['path'] . '.v' . $v['version'], $user . '/files_trashbin/versions/' . $filename . '.v' . $v['version'] . '.d' . $timestamp);
+                }
+            }
+        }
+    }
+
+    /**
+     * Move a file or folder on storage level
+     *
+     * @param View $view
+     * @param string $source
+     * @param string $target
+     * @return bool
+     */
+    private static function move(View $view, $source, $target) {
+        /** @var \OC\Files\Storage\Storage $sourceStorage */
+        list($sourceStorage, $sourceInternalPath) = $view->resolvePath($source);
+        /** @var \OC\Files\Storage\Storage $targetStorage */
+        list($targetStorage, $targetInternalPath) = $view->resolvePath($target);
+        /** @var \OC\Files\Storage\Storage $ownerTrashStorage */
+
+        $result = $targetStorage->moveFromStorage($sourceStorage, $sourceInternalPath, $targetInternalPath);
+        if ($result) {
+            $targetStorage->getUpdater()->renameFromStorage($sourceStorage, $sourceInternalPath, $targetInternalPath);
+        }
+        return $result;
+    }
+
+    /**
+     * Copy a file or folder on storage level
+     *
+     * @param View $view
+     * @param string $source
+     * @param string $target
+     * @return bool
+     */
+    private static function copy(View $view, $source, $target) {
+        /** @var \OC\Files\Storage\Storage $sourceStorage */
+        list($sourceStorage, $sourceInternalPath) = $view->resolvePath($source);
+        /** @var \OC\Files\Storage\Storage $targetStorage */
+        list($targetStorage, $targetInternalPath) = $view->resolvePath($target);
+        /** @var \OC\Files\Storage\Storage $ownerTrashStorage */
+
+        $result = $targetStorage->copyFromStorage($sourceStorage, $sourceInternalPath, $targetInternalPath);
+        if ($result) {
+            $targetStorage->getUpdater()->update($targetInternalPath);
+        }
+        return $result;
+    }
+
+    /**
+     * Restore a file or folder from trash bin
+     *
+     * @param string $file path to the deleted file/folder relative to "files_trashbin/files/",
+     * including the timestamp suffix ".d12345678"
+     * @param string $filename name of the file/folder
+     * @param int $timestamp time when the file/folder was deleted
+     *
+     * @return bool true on success, false otherwise
+     */
+    public static function restore($file, $filename, $timestamp) {
+        $user = User::getUser();
+        $view = new View('/' . $user);
+
+        $location = '';
+        if ($timestamp) {
+            $location = self::getLocation($user, $filename, $timestamp);
+            if ($location === false) {
+                \OCP\Util::writeLog('files_trashbin', 'trash bin database inconsistent!', \OCP\Util::ERROR);
+            } else {
+                // if location no longer exists, restore file in the root directory
+                if ($location !== '/' &&
+                    (!$view->is_dir('files/' . $location) ||
+                        !$view->isCreatable('files/' . $location))
+                ) {
+                    $location = '';
+                }
+            }
+        }
+
+        // we need a  extension in case a file/dir with the same name already exists
+        $uniqueFilename = self::getUniqueFilename($location, $filename, $view);
+
+        $source = Filesystem::normalizePath('files_trashbin/files/' . $file);
+        $target = Filesystem::normalizePath('files/' . $location . '/' . $uniqueFilename);
+        if (!$view->file_exists($source)) {
+            return false;
+        }
+        $mtime = $view->filemtime($source);
+
+        // restore file
+        $restoreResult = $view->rename($source, $target);
+
+        // handle the restore result
+        if ($restoreResult) {
+            $fakeRoot = $view->getRoot();
+            $view->chroot('/' . $user . '/files');
+            $view->touch('/' . $location . '/' . $uniqueFilename, $mtime);
+            $view->chroot($fakeRoot);
+            \OCP\Util::emitHook('\OCA\Files_Trashbin\Trashbin', 'post_restore', array('filePath' => Filesystem::normalizePath('/' . $location . '/' . $uniqueFilename),
+                'trashPath' => Filesystem::normalizePath($file)));
+
+            self::restoreVersions($view, $file, $filename, $uniqueFilename, $location, $timestamp);
+
+            if ($timestamp) {
+                $query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_trash` WHERE `user`=? AND `id`=? AND `timestamp`=?');
+                $query->execute(array($user, $filename, $timestamp));
+            }
+
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * restore versions from trash bin
+     *
+     * @param View $view file view
+     * @param string $file complete path to file
+     * @param string $filename name of file once it was deleted
+     * @param string $uniqueFilename new file name to restore the file without overwriting existing files
+     * @param string $location location if file
+     * @param int $timestamp deletion time
+     * @return false|null
+     */
+    private static function restoreVersions(View $view, $file, $filename, $uniqueFilename, $location, $timestamp) {
+
+        if (\OCP\App::isEnabled('files_versions')) {
+
+            $user = User::getUser();
+            $rootView = new View('/');
+
+            $target = Filesystem::normalizePath('/' . $location . '/' . $uniqueFilename);
+
+            list($owner, $ownerPath) = self::getUidAndFilename($target);
+
+            // file has been deleted in between
+            if (empty($ownerPath)) {
+                return false;
+            }
+
+            if ($timestamp) {
+                $versionedFile = $filename;
+            } else {
+                $versionedFile = $file;
+            }
+
+            if ($view->is_dir('/files_trashbin/versions/' . $file)) {
+                $rootView->rename(Filesystem::normalizePath($user . '/files_trashbin/versions/' . $file), Filesystem::normalizePath($owner . '/files_versions/' . $ownerPath));
+            } else if ($versions = self::getVersionsFromTrash($versionedFile, $timestamp, $user)) {
+                foreach ($versions as $v) {
+                    if ($timestamp) {
+                        $rootView->rename($user . '/files_trashbin/versions/' . $versionedFile . '.v' . $v . '.d' . $timestamp, $owner . '/files_versions/' . $ownerPath . '.v' . $v);
+                    } else {
+                        $rootView->rename($user . '/files_trashbin/versions/' . $versionedFile . '.v' . $v, $owner . '/files_versions/' . $ownerPath . '.v' . $v);
+                    }
+                }
+            }
+        }
+    }
+
+    /**
+     * delete all files from the trash
+     */
+    public static function deleteAll() {
+        $user = User::getUser();
+        $view = new View('/' . $user);
+        $fileInfos = $view->getDirectoryContent('files_trashbin/files');
+
+        // Array to store the relative path in (after the file is deleted, the view won't be able to relativise the path anymore)
+        $filePaths = array();
+        foreach($fileInfos as $fileInfo){
+            $filePaths[] = $view->getRelativePath($fileInfo->getPath());
+        }
+        unset($fileInfos); // save memory
+
+        // Bulk PreDelete-Hook
+        \OC_Hook::emit('\OCP\Trashbin', 'preDeleteAll', array('paths' => $filePaths));
+
+        // Single-File Hooks
+        foreach($filePaths as $path){
+            self::emitTrashbinPreDelete($path);
+        }
+
+        // actual file deletion
+        $view->deleteAll('files_trashbin');
+        $query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_trash` WHERE `user`=?');
+        $query->execute(array($user));
+
+        // Bulk PostDelete-Hook
+        \OC_Hook::emit('\OCP\Trashbin', 'deleteAll', array('paths' => $filePaths));
+
+        // Single-File Hooks
+        foreach($filePaths as $path){
+            self::emitTrashbinPostDelete($path);
+        }
+
+        $view->mkdir('files_trashbin');
+        $view->mkdir('files_trashbin/files');
+
+        return true;
+    }
+
+    /**
+     * wrapper function to emit the 'preDelete' hook of \OCP\Trashbin before a file is deleted
+     * @param string $path
+     */
+    protected static function emitTrashbinPreDelete($path){
+        \OC_Hook::emit('\OCP\Trashbin', 'preDelete', array('path' => $path));
+    }
+
+    /**
+     * wrapper function to emit the 'delete' hook of \OCP\Trashbin after a file has been deleted
+     * @param string $path
+     */
+    protected static function emitTrashbinPostDelete($path){
+        \OC_Hook::emit('\OCP\Trashbin', 'delete', array('path' => $path));
+    }
+
+    /**
+     * delete file from trash bin permanently
+     *
+     * @param string $filename path to the file
+     * @param string $user
+     * @param int $timestamp of deletion time
+     *
+     * @return int size of deleted files
+     */
+    public static function delete($filename, $user, $timestamp = null) {
+        $view = new View('/' . $user);
+        $size = 0;
+
+        if ($timestamp) {
+            $query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_trash` WHERE `user`=? AND `id`=? AND `timestamp`=?');
+            $query->execute(array($user, $filename, $timestamp));
+            $file = $filename . '.d' . $timestamp;
+        } else {
+            $file = $filename;
+        }
+
+        $size += self::deleteVersions($view, $file, $filename, $timestamp, $user);
+
+        if ($view->is_dir('/files_trashbin/files/' . $file)) {
+            $size += self::calculateSize(new View('/' . $user . '/files_trashbin/files/' . $file));
+        } else {
+            $size += $view->filesize('/files_trashbin/files/' . $file);
+        }
+        self::emitTrashbinPreDelete('/files_trashbin/files/' . $file);
+        $view->unlink('/files_trashbin/files/' . $file);
+        self::emitTrashbinPostDelete('/files_trashbin/files/' . $file);
+
+        return $size;
+    }
+
+    /**
+     * @param View $view
+     * @param string $file
+     * @param string $filename
+     * @param integer|null $timestamp
+     * @param string $user
+     * @return int
+     */
+    private static function deleteVersions(View $view, $file, $filename, $timestamp, $user) {
+        $size = 0;
+        if (\OCP\App::isEnabled('files_versions')) {
+            if ($view->is_dir('files_trashbin/versions/' . $file)) {
+                $size += self::calculateSize(new View('/' . $user . '/files_trashbin/versions/' . $file));
+                $view->unlink('files_trashbin/versions/' . $file);
+            } else if ($versions = self::getVersionsFromTrash($filename, $timestamp, $user)) {
+                foreach ($versions as $v) {
+                    if ($timestamp) {
+                        $size += $view->filesize('/files_trashbin/versions/' . $filename . '.v' . $v . '.d' . $timestamp);
+                        $view->unlink('/files_trashbin/versions/' . $filename . '.v' . $v . '.d' . $timestamp);
+                    } else {
+                        $size += $view->filesize('/files_trashbin/versions/' . $filename . '.v' . $v);
+                        $view->unlink('/files_trashbin/versions/' . $filename . '.v' . $v);
+                    }
+                }
+            }
+        }
+        return $size;
+    }
+
+    /**
+     * check to see whether a file exists in trashbin
+     *
+     * @param string $filename path to the file
+     * @param int $timestamp of deletion time
+     * @return bool true if file exists, otherwise false
+     */
+    public static function file_exists($filename, $timestamp = null) {
+        $user = User::getUser();
+        $view = new View('/' . $user);
+
+        if ($timestamp) {
+            $filename = $filename . '.d' . $timestamp;
+        } else {
+            $filename = $filename;
+        }
+
+        $target = Filesystem::normalizePath('files_trashbin/files/' . $filename);
+        return $view->file_exists($target);
+    }
+
+    /**
+     * deletes used space for trash bin in db if user was deleted
+     *
+     * @param string $uid id of deleted user
+     * @return bool result of db delete operation
+     */
+    public static function deleteUser($uid) {
+        $query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_trash` WHERE `user`=?');
+        return $query->execute(array($uid));
+    }
+
+    /**
+     * calculate remaining free space for trash bin
+     *
+     * @param integer $trashbinSize current size of the trash bin
+     * @param string $user
+     * @return int available free space for trash bin
+     */
+    private static function calculateFreeSpace($trashbinSize, $user) {
+        $softQuota = true;
+        $userObject = \OC::$server->getUserManager()->get($user);
+        if(is_null($userObject)) {
+            return 0;
+        }
+        $quota = $userObject->getQuota();
+        if ($quota === null || $quota === 'none') {
+            $quota = Filesystem::free_space('/');
+            $softQuota = false;
+            // inf or unknown free space
+            if ($quota < 0) {
+                $quota = PHP_INT_MAX;
+            }
+        } else {
+            $quota = \OCP\Util::computerFileSize($quota);
+        }
+
+        // calculate available space for trash bin
+        // subtract size of files and current trash bin size from quota
+        if ($softQuota) {
+            $userFolder = \OC::$server->getUserFolder($user);
+            if(is_null($userFolder)) {
+                return 0;
+            }
+            $free = $quota - $userFolder->getSize(); // remaining free space for user
+            if ($free > 0) {
+                $availableSpace = ($free * self::DEFAULTMAXSIZE / 100) - $trashbinSize; // how much space can be used for versions
+            } else {
+                $availableSpace = $free - $trashbinSize;
+            }
+        } else {
+            $availableSpace = $quota;
+        }
+
+        return $availableSpace;
+    }
+
+    /**
+     * resize trash bin if necessary after a new file was added to ownCloud
+     *
+     * @param string $user user id
+     */
+    public static function resizeTrash($user) {
+
+        $size = self::getTrashbinSize($user);
+
+        $freeSpace = self::calculateFreeSpace($size, $user);
+
+        if ($freeSpace < 0) {
+            self::scheduleExpire($user);
+        }
+    }
+
+    /**
+     * clean up the trash bin
+     *
+     * @param string $user
+     */
+    public static function expire($user) {
+        $trashBinSize = self::getTrashbinSize($user);
+        $availableSpace = self::calculateFreeSpace($trashBinSize, $user);
+
+        $dirContent = Helper::getTrashFiles('/', $user, 'mtime');
+
+        // delete all files older then $retention_obligation
+        list($delSize, $count) = self::deleteExpiredFiles($dirContent, $user);
+
+        $availableSpace += $delSize;
+
+        // delete files from trash until we meet the trash bin size limit again
+        self::deleteFiles(array_slice($dirContent, $count), $user, $availableSpace);
+    }
+
+    /**
+     * @param string $user
+     */
+    private static function scheduleExpire($user) {
+        // let the admin disable auto expire
+        $application = new Application();
+        $expiration = $application->getContainer()->query('Expiration');
+        if ($expiration->isEnabled()) {
+            \OC::$server->getCommandBus()->push(new Expire($user));
+        }
+    }
+
+    /**
+     * if the size limit for the trash bin is reached, we delete the oldest
+     * files in the trash bin until we meet the limit again
+     *
+     * @param array $files
+     * @param string $user
+     * @param int $availableSpace available disc space
+     * @return int size of deleted files
+     */
+    protected static function deleteFiles($files, $user, $availableSpace) {
+        $application = new Application();
+        $expiration = $application->getContainer()->query('Expiration');
+        $size = 0;
+
+        if ($availableSpace < 0) {
+            foreach ($files as $file) {
+                if ($availableSpace < 0 && $expiration->isExpired($file['mtime'], true)) {
+                    $tmp = self::delete($file['name'], $user, $file['mtime']);
+                    \OCP\Util::writeLog('files_trashbin', 'remove "' . $file['name'] . '" (' . $tmp . 'B) to meet the limit of trash bin size (50% of available quota)', \OCP\Util::INFO);
+                    $availableSpace += $tmp;
+                    $size += $tmp;
+                } else {
+                    break;
+                }
+            }
+        }
+        return $size;
+    }
+
+    /**
+     * delete files older then max storage time
+     *
+     * @param array $files list of files sorted by mtime
+     * @param string $user
+     * @return integer[] size of deleted files and number of deleted files
+     */
+    public static function deleteExpiredFiles($files, $user) {
+        $application = new Application();
+        $expiration = $application->getContainer()->query('Expiration');
+        $size = 0;
+        $count = 0;
+        foreach ($files as $file) {
+            $timestamp = $file['mtime'];
+            $filename = $file['name'];
+            if ($expiration->isExpired($timestamp)) {
+                $count++;
+                $size += self::delete($filename, $user, $timestamp);
+                \OC::$server->getLogger()->info(
+                    'Remove "' . $filename . '" from trashbin because it exceeds max retention obligation term.',
+                    ['app' => 'files_trashbin']
+                );
+            } else {
+                break;
+            }
+        }
+
+        return array($size, $count);
+    }
+
+    /**
+     * recursive copy to copy a whole directory
+     *
+     * @param string $source source path, relative to the users files directory
+     * @param string $destination destination path relative to the users root directoy
+     * @param View $view file view for the users root directory
+     * @return int
+     * @throws Exceptions\CopyRecursiveException
+     */
+    private static function copy_recursive($source, $destination, View $view) {
+        $size = 0;
+        if ($view->is_dir($source)) {
+            $view->mkdir($destination);
+            $view->touch($destination, $view->filemtime($source));
+            foreach ($view->getDirectoryContent($source) as $i) {
+                $pathDir = $source . '/' . $i['name'];
+                if ($view->is_dir($pathDir)) {
+                    $size += self::copy_recursive($pathDir, $destination . '/' . $i['name'], $view);
+                } else {
+                    $size += $view->filesize($pathDir);
+                    $result = $view->copy($pathDir, $destination . '/' . $i['name']);
+                    if (!$result) {
+                        throw new \OCA\Files_Trashbin\Exceptions\CopyRecursiveException();
+                    }
+                    $view->touch($destination . '/' . $i['name'], $view->filemtime($pathDir));
+                }
+            }
+        } else {
+            $size += $view->filesize($source);
+            $result = $view->copy($source, $destination);
+            if (!$result) {
+                throw new \OCA\Files_Trashbin\Exceptions\CopyRecursiveException();
+            }
+            $view->touch($destination, $view->filemtime($source));
+        }
+        return $size;
+    }
+
+    /**
+     * find all versions which belong to the file we want to restore
+     *
+     * @param string $filename name of the file which should be restored
+     * @param int $timestamp timestamp when the file was deleted
+     * @return array
+     */
+    private static function getVersionsFromTrash($filename, $timestamp, $user) {
+        $view = new View('/' . $user . '/files_trashbin/versions');
+        $versions = array();
+
+        //force rescan of versions, local storage may not have updated the cache
+        if (!self::$scannedVersions) {
+            /** @var \OC\Files\Storage\Storage $storage */
+            list($storage,) = $view->resolvePath('/');
+            $storage->getScanner()->scan('files_trashbin/versions');
+            self::$scannedVersions = true;
+        }
+
+        if ($timestamp) {
+            // fetch for old versions
+            $matches = $view->searchRaw($filename . '.v%.d' . $timestamp);
+            $offset = -strlen($timestamp) - 2;
+        } else {
+            $matches = $view->searchRaw($filename . '.v%');
+        }
+
+        if (is_array($matches)) {
+            foreach ($matches as $ma) {
+                if ($timestamp) {
+                    $parts = explode('.v', substr($ma['path'], 0, $offset));
+                    $versions[] = (end($parts));
+                } else {
+                    $parts = explode('.v', $ma);
+                    $versions[] = (end($parts));
+                }
+            }
+        }
+        return $versions;
+    }
+
+    /**
+     * find unique extension for restored file if a file with the same name already exists
+     *
+     * @param string $location where the file should be restored
+     * @param string $filename name of the file
+     * @param View $view filesystem view relative to users root directory
+     * @return string with unique extension
+     */
+    private static function getUniqueFilename($location, $filename, View $view) {
+        $ext = pathinfo($filename, PATHINFO_EXTENSION);
+        $name = pathinfo($filename, PATHINFO_FILENAME);
+        $l = \OC::$server->getL10N('files_trashbin');
+
+        $location = '/' . trim($location, '/');
+
+        // if extension is not empty we set a dot in front of it
+        if ($ext !== '') {
+            $ext = '.' . $ext;
+        }
+
+        if ($view->file_exists('files' . $location . '/' . $filename)) {
+            $i = 2;
+            $uniqueName = $name . " (" . $l->t("restored") . ")" . $ext;
+            while ($view->file_exists('files' . $location . '/' . $uniqueName)) {
+                $uniqueName = $name . " (" . $l->t("restored") . " " . $i . ")" . $ext;
+                $i++;
+            }
+
+            return $uniqueName;
+        }
+
+        return $filename;
+    }
+
+    /**
+     * get the size from a given root folder
+     *
+     * @param View $view file view on the root folder
+     * @return integer size of the folder
+     */
+    private static function calculateSize($view) {
+        $root = \OC::$server->getConfig()->getSystemValue('datadirectory', \OC::$SERVERROOT . '/data') . $view->getAbsolutePath('');
+        if (!file_exists($root)) {
+            return 0;
+        }
+        $iterator = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($root), \RecursiveIteratorIterator::CHILD_FIRST);
+        $size = 0;
+
+        /**
+         * RecursiveDirectoryIterator on an NFS path isn't iterable with foreach
+         * This bug is fixed in PHP 5.5.9 or before
+         * See #8376
+         */
+        $iterator->rewind();
+        while ($iterator->valid()) {
+            $path = $iterator->current();
+            $relpath = substr($path, strlen($root) - 1);
+            if (!$view->is_dir($relpath)) {
+                $size += $view->filesize($relpath);
+            }
+            $iterator->next();
+        }
+        return $size;
+    }
+
+    /**
+     * get current size of trash bin from a given user
+     *
+     * @param string $user user who owns the trash bin
+     * @return integer trash bin size
+     */
+    private static function getTrashbinSize($user) {
+        $view = new View('/' . $user);
+        $fileInfo = $view->getFileInfo('/files_trashbin');
+        return isset($fileInfo['size']) ? $fileInfo['size'] : 0;
+    }
+
+    /**
+     * register hooks
+     */
+    public static function registerHooks() {
+        // create storage wrapper on setup
+        \OCP\Util::connectHook('OC_Filesystem', 'preSetup', 'OCA\Files_Trashbin\Storage', 'setupStorage');
+        //Listen to delete user signal
+        \OCP\Util::connectHook('OC_User', 'pre_deleteUser', 'OCA\Files_Trashbin\Hooks', 'deleteUser_hook');
+        //Listen to post write hook
+        \OCP\Util::connectHook('OC_Filesystem', 'post_write', 'OCA\Files_Trashbin\Hooks', 'post_write_hook');
+        // pre and post-rename, disable trash logic for the copy+unlink case
+        \OCP\Util::connectHook('OC_Filesystem', 'delete', 'OCA\Files_Trashbin\Trashbin', 'ensureFileScannedHook');
+        \OCP\Util::connectHook('OC_Filesystem', 'rename', 'OCA\Files_Trashbin\Storage', 'preRenameHook');
+        \OCP\Util::connectHook('OC_Filesystem', 'post_rename', 'OCA\Files_Trashbin\Storage', 'postRenameHook');
+    }
+
+    /**
+     * check if trash bin is empty for a given user
+     *
+     * @param string $user
+     * @return bool
+     */
+    public static function isEmpty($user) {
+
+        $view = new View('/' . $user . '/files_trashbin');
+        if ($view->is_dir('/files') && $dh = $view->opendir('/files')) {
+            while ($file = readdir($dh)) {
+                if (!Filesystem::isIgnoredDir($file)) {
+                    return false;
+                }
+            }
+        }
+        return true;
+    }
+
+    /**
+     * @param $path
+     * @return string
+     */
+    public static function preview_icon($path) {
+        return \OCP\Util::linkToRoute('core_ajax_trashbin_preview', array('x' => 32, 'y' => 32, 'file' => $path));
+    }
 }