Move files_trashbin to PSR-4 (#24570)

1 files changed, 926 insertions, 0 deletions

diff --git a/apps/files_trashbin/lib/Trashbin.php b/apps/files_trashbin/lib/Trashbin.php
new file mode 100644
index 00000000000..52692950a65
--- /dev/null
+++ b/apps/files_trashbin/lib/Trashbin.php
@@ -0,0 +1,926 @@
+<?php
+/**
+ * @author Bart Visscher <bartv@thisnet.nl>
+ * @author Bastien Ho <bastienho@urbancube.fr>
+ * @author Björn Schießle <schiessle@owncloud.com>
+ * @author Florin Peter <github@florin-peter.de>
+ * @author Georg Ehrke <georg@owncloud.com>
+ * @author Jörn Friedrich Dreyer <jfd@butonic.de>
+ * @author Lukas Reschke <lukas@owncloud.com>
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Qingping Hou <dave2008713@gmail.com>
+ * @author Robin Appelman <icewind@owncloud.com>
+ * @author Robin McCorkell <robin@mccorkell.me.uk>
+ * @author Roeland Jago Douma <rullzer@owncloud.com>
+ * @author Sjors van der Pluijm <sjors@desjors.nl>
+ * @author Thomas Müller <thomas.mueller@tmit.eu>
+ * @author Victor Dubiniuk <dubiniuk@owncloud.com>
+ * @author Vincent Petry <pvince81@owncloud.com>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\Files_Trashbin;
+
+use OC\Files\Filesystem;
+use OC\Files\View;
+use OCA\Files_Trashbin\AppInfo\Application;
+use OCA\Files_Trashbin\Command\Expire;
+use OCP\Files\NotFoundException;
+use OCP\User;
+
+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)) {
+			$uid = User::getUser();
+		}
+		Filesystem::initMountPoints($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 $file_path path to the deleted file/directory relative to the files root directory
+	 * @return bool
+	 */
+	public static function move2trash($file_path) {
+		// get the user for which the filesystem is setup
+		$root = Filesystem::getRoot();
+		list(, $user) = explode('/', $root);
+		list($owner, $ownerPath) = self::getUidAndFilename($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
+			$sourceStorage->unlink($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, $timestamp);
+
+			// if owner !== user we need to also add a copy to the owners trash
+			if ($user !== $owner) {
+				self::copyFilesToUser($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);
+		$view->deleteAll('files_trashbin');
+		$query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_trash` WHERE `user`=?');
+		$query->execute(array($user));
+		$view->mkdir('files_trashbin');
+		$view->mkdir('files_trashbin/files');
+
+		return true;
+	}
+
+	/**
+	 * 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);
+		}
+		\OC_Hook::emit('\OCP\Trashbin', 'preDelete', array('path' => '/files_trashbin/files/' . $file));
+		$view->unlink('/files_trashbin/files/' . $file);
+		\OC_Hook::emit('\OCP\Trashbin', 'delete', array('path' => '/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') . $view->getAbsolutePath('');
+		if (!file_exists($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));
+	}
+}