diff --git a/apps/files/admin.php b/apps/files/admin.php
index 547f2bd7ddba5483693a8198c08fa848749a4edc..e8b3cb0aca0715fa3a38e865164a66798e7db32d 100644
--- a/apps/files/admin.php
+++ b/apps/files/admin.php
@@ -63,4 +63,3 @@ $tmpl->assign( 'maxPossibleUploadSize', $maxUploadFilesizePossible);
 $tmpl->assign( 'allowZipDownload', $allowZipDownload);
 $tmpl->assign( 'maxZipInputSize', $maxZipInputSize);
 return $tmpl->fetchPage();
-
diff --git a/apps/files/css/files.css b/apps/files/css/files.css
index f15cd514241831ae16c6821e07ae0019c5f513a8..14482c5edb5f674a0a5c64ba26926599b781ef2e 100644
--- a/apps/files/css/files.css
+++ b/apps/files/css/files.css
@@ -89,4 +89,3 @@ a.action>img { max-height:16px; max-width:16px; vertical-align:text-bottom; }
 #scanning-message{ top:40%; left:40%; position:absolute; display:none; }
 
 div.crumb a{ padding: 0.9em 0 0.7em 0; }
-
diff --git a/apps/files/js/filelist.js b/apps/files/js/filelist.js
index 100a236872242e88d8db3f31a5ef9e306838088e..870437ae672de8319e6711536fac3ade12951b2d 100644
--- a/apps/files/js/filelist.js
+++ b/apps/files/js/filelist.js
@@ -150,7 +150,7 @@ var FileList={
 			if (newname != name) {
 				if (FileList.checkName(name, newname, false)) {
 					newname = name;
-				} else {					
+				} else {
 					$.get(OC.filePath('files','ajax','rename.php'), { dir : $('#dir').val(), newname: newname, file: name },function(result) {
 						if (!result || result.status == 'error') {
 							OC.dialogs.alert(result.data.message, 'Error moving file');
@@ -158,7 +158,7 @@ var FileList={
 						}
 						tr.data('renaming',false);
 					});
-					
+
 				}
 			}
 			tr.attr('data-file', newname);
@@ -264,9 +264,9 @@ var FileList={
 		if (FileList.lastAction) {
 			FileList.lastAction();
 		}
-		
+
 		FileList.prepareDeletion(files);
-		
+
 		if (!FileList.useUndo) {
 			FileList.lastAction();
 		} else {
diff --git a/apps/files/js/files.js b/apps/files/js/files.js
index c5333f2fafb16d9a0b058a9f19d3faebe40c0b35..777a5ec647e0a4470f0e97c3a13beae6def394f9 100644
--- a/apps/files/js/files.js
+++ b/apps/files/js/files.js
@@ -199,7 +199,7 @@ $(document).ready(function() {
 	$(document).bind('drop dragover', function (e) {
 			e.preventDefault(); // prevent browser from doing anything, if file isn't dropped in dropZone
 	});
-	 
+
 	if ( document.getElementById("data-upload-form") ) {
 	$(function() {
 		$('.file_upload_start').fileupload({
diff --git a/apps/files/templates/part.list.php b/apps/files/templates/part.list.php
index 1329b5dc5cd0a5cbab338baf453188e7b8c45964..0f5b839b180a52c65aa3b258c2ef7c84872b38cd 100644
--- a/apps/files/templates/part.list.php
+++ b/apps/files/templates/part.list.php
@@ -6,7 +6,7 @@
 		}
 		?>
 		</script>
-		
+
 		<?php foreach($_['files'] as $file):
 			$simple_file_size = OCP\simple_file_size($file['size']);
 			$simple_size_color = intval(200-$file['size']/(1024*1024)*2); // the bigger the file, the darker the shade of grey; megabytes*2
diff --git a/apps/files_external/ajax/addRootCertificate.php b/apps/files_external/ajax/addRootCertificate.php
index e0a0239c9543b6fdd4cb3208ce0a43e99e1ee483..72eb30009d1a00406914c44b15eddba3456d4e89 100644
--- a/apps/files_external/ajax/addRootCertificate.php
+++ b/apps/files_external/ajax/addRootCertificate.php
@@ -3,23 +3,23 @@
 OCP\JSON::checkAppEnabled('files_external');
 
 if ( !($filename = $_FILES['rootcert_import']['name']) ) {
-	header("Location: settings/personal.php");
+	header("Location: settings/personal.php");
 	exit;
 }
 
-$fh = fopen($_FILES['rootcert_import']['tmp_name'], 'r');
-$data = fread($fh, filesize($_FILES['rootcert_import']['tmp_name']));
+$fh = fopen($_FILES['rootcert_import']['tmp_name'], 'r');
+$data = fread($fh, filesize($_FILES['rootcert_import']['tmp_name']));
 fclose($fh);
 $filename = $_FILES['rootcert_import']['name'];
-
-$view = new \OC_FilesystemView('/'.\OCP\User::getUser().'/files_external/uploads');
+
+$view = new \OC_FilesystemView('/'.\OCP\User::getUser().'/files_external/uploads');
 if (!$view->file_exists('')) $view->mkdir('');
 
 $isValid = openssl_pkey_get_public($data);
 
 //maybe it was just the wrong file format, try to convert it...
 if ($isValid == false) {
-	$data = chunk_split(base64_encode($data), 64, "\n");
+	$data = chunk_split(base64_encode($data), 64, "\n");
 	$data = "-----BEGIN CERTIFICATE-----\n".$data."-----END CERTIFICATE-----\n";
 	$isValid = openssl_pkey_get_public($data);
 }
diff --git a/apps/files_external/ajax/removeRootCertificate.php b/apps/files_external/ajax/removeRootCertificate.php
index 6871b0fd1d4eaea09c6bd9e0110fd2e0d98cd5da..664b3937e97bd6f84c04d27f3de36f6097fb0083 100644
--- a/apps/files_external/ajax/removeRootCertificate.php
+++ b/apps/files_external/ajax/removeRootCertificate.php
@@ -11,4 +11,3 @@ if ( $view->file_exists($file) ) {
 	$view->unlink($file);
 	OC_Mount_Config::createCertificateBundle();
 }
-
diff --git a/apps/files_external/lib/config.php b/apps/files_external/lib/config.php
index 0a576f06f1f6884f8e9279fdf4b869f633a7cc8b..068475783cda9833ad3763e489f3a293a7eb1f57 100755
--- a/apps/files_external/lib/config.php
+++ b/apps/files_external/lib/config.php
@@ -120,10 +120,10 @@ class OC_Mount_Config {
 			$dir = $dir.'/'.$pathPart;
 			if ( !$view->file_exists($dir)) {
 				$view->mkdir($dir);
-			}		
+			}
 		}
 	}
-	
+
 
 	/**
 	* Add a mount point to the filesystem
@@ -160,7 +160,7 @@ class OC_Mount_Config {
 						self::addMountPointDirectory($view, $path);
 					}
 					break;
-				case 'group' : 
+				case 'group' :
 					$groupMembers = OC_Group::usersInGroups(array($applicable));
 					foreach ( $groupMembers as $user ) {
 						$path =  $user.'/files/'.ltrim($mountPoint, '/');
diff --git a/apps/files_sharing/lib/share/folder.php b/apps/files_sharing/lib/share/folder.php
index e29e9b7e002fba685424a6b7d1a2f8a7f572314c..bddda99f8bbac0c6e21d0e899b0d0264e687218a 100644
--- a/apps/files_sharing/lib/share/folder.php
+++ b/apps/files_sharing/lib/share/folder.php
@@ -59,7 +59,7 @@ class OC_Share_Backend_Folder extends OC_Share_Backend_File implements OCP\Share
 			$parents = array();
 			while ($file = $result->fetchRow()) {
 				$children[] = array('source' => $file['id'], 'file_path' => $file['name']);
-				// If a child folder is found look inside it 
+				// If a child folder is found look inside it
 				if ($file['mimetype'] == 'httpd/unix-directory') {
 					$parents[] = $file['id'];
 				}
diff --git a/apps/files_sharing/public.php b/apps/files_sharing/public.php
index e9f318efd9da9c0c213bcf10476de1ec15a6d48f..d79f19559781d64c42922592294b4caef5916eeb 100644
--- a/apps/files_sharing/public.php
+++ b/apps/files_sharing/public.php
@@ -45,10 +45,10 @@ if (isset($_GET['file']) || isset($_GET['dir'])) {
 			}
 			if (isset($linkItem['share_with'])) {
 				// Check password
-				if (isset($_GET['file'])) {
-					$url = OCP\Util::linkToPublic('files').'&file='.$_GET['file'];
-				} else {
-					$url = OCP\Util::linkToPublic('files').'&dir='.$_GET['dir'];
+				if (isset($_GET['file'])) {
+					$url = OCP\Util::linkToPublic('files').'&file='.$_GET['file'];
+				} else {
+					$url = OCP\Util::linkToPublic('files').'&dir='.$_GET['dir'];
 				}
 				if (isset($_POST['password'])) {
 					$password = $_POST['password'];
@@ -98,7 +98,7 @@ if (isset($_GET['file']) || isset($_GET['dir'])) {
 				} else { // download a single shared file
 					OC_Files::get("", $path, $_SERVER['REQUEST_METHOD'] == 'HEAD' ? true : false);
 				}
-				
+
 			} else {
 				OCP\Util::addStyle('files_sharing', 'public');
 				OCP\Util::addScript('files_sharing', 'public');
@@ -134,7 +134,7 @@ if (isset($_GET['file']) || isset($_GET['dir'])) {
 						if ($i != '') {
 							if ($i != $baseDir) {
 								$pathtohere .= '/'.$i;
-							}						
+							}
 							if ( strlen($pathtohere) <  strlen($_GET['dir'])) {
 								continue;
 							}
diff --git a/apps/files_versions/js/versions.js b/apps/files_versions/js/versions.js
index 07c5655560e0dbf28991b025f49c2574490ca168..426d521df828134f55f9fc3ee805dc6b60b27f65 100644
Binary files a/apps/files_versions/js/versions.js and b/apps/files_versions/js/versions.js differ
diff --git a/apps/files_versions/lib/versions.php b/apps/files_versions/lib/versions.php
index b68fa28a1ff3e9e01577129cd2cae9ed39f8b3a1..076094ae7816977fdd6f5662a18ef53c87ce5550 100644
--- a/apps/files_versions/lib/versions.php
+++ b/apps/files_versions/lib/versions.php
@@ -106,7 +106,7 @@ class Storage {
 
 
 			// create all parent folders
-			$info=pathinfo($filename);
+			$info=pathinfo($filename);
 			if(!file_exists($versionsFolderName.'/'.$info['dirname'])) {
 				mkdir($versionsFolderName.'/'.$info['dirname'],0750,true);
 			}
diff --git a/lib/app.php b/lib/app.php
index 395230156f68c48e626165b2924b6beef51520f0..594f057709126a8bd43a469e9a00157d6e74c6ab 100755
--- a/lib/app.php
+++ b/lib/app.php
@@ -63,7 +63,7 @@ class OC_App{
 
 		if (!defined('DEBUG') || !DEBUG) {
 			if (is_null($types)
-			    && empty(OC_Util::$core_scripts) 
+			    && empty(OC_Util::$core_scripts)
 			    && empty(OC_Util::$core_styles)) {
 				OC_Util::$core_scripts = OC_Util::$scripts;
 				OC_Util::$scripts = array();
@@ -458,7 +458,7 @@ class OC_App{
 			}
 		}
 		self::$appInfo[$appid]=$data;
-		
+
 		return $data;
 	}
 
@@ -545,34 +545,34 @@ class OC_App{
 	 * @todo: change the name of this method to getInstalledApps, which is more accurate
 	 */
 	public static function getAllApps() {
-	
+
 		$apps=array();
-		
+
 		foreach ( OC::$APPSROOTS as $apps_dir ) {
 			if(! is_readable($apps_dir['path'])) {
 				OC_Log::write('core', 'unable to read app folder : ' .$apps_dir['path'] , OC_Log::WARN);
 				continue;
 			}
 			$dh = opendir( $apps_dir['path'] );
-			
+
 			while( $file = readdir( $dh ) ) {
-			
-				if ( 
-				$file[0] != '.' 
-				and is_file($apps_dir['path'].'/'.$file.'/appinfo/app.php' ) 
+
+				if (
+				$file[0] != '.'
+				and is_file($apps_dir['path'].'/'.$file.'/appinfo/app.php' )
 				) {
-				
+
 					$apps[] = $file;
-					
+
 				}
-				
+
 			}
-			
+
 		}
-		
+
 		return $apps;
 	}
-	
+
 	/**
 	 * @brief: get a list of all apps on apps.owncloud.com
 	 * @return array, multi-dimensional array of apps. Keys: id, name, type, typename, personid, license, detailpage, preview, changed, description
@@ -584,7 +584,7 @@ class OC_App{
 			if ( ! $categories = array_keys( $catagoryNames ) ) {
 				return false;
 			}
-			
+
 			$page = 0;
 			$remoteApps = OC_OCSClient::getApplications( $categories, $page, $filter );
 			$app1 = array();
@@ -659,7 +659,7 @@ class OC_App{
 		$version = OC_Util::getVersion();
 		foreach($apps as $app) {
 			// check if the app is compatible with this version of ownCloud
-			$info = OC_App::getAppInfo($app);			
+			$info = OC_App::getAppInfo($app);
 			if(!isset($info['require']) or (($version[0].'.'.$version[1])>$info['require'])) {
 				OC_Log::write('core', 'App "'.$info['name'].'" ('.$app.') can\'t be used because it is not compatible with this version of ownCloud', OC_Log::ERROR);
 				OC_App::disable( $app );
diff --git a/lib/connector/sabre/directory.php b/lib/connector/sabre/directory.php
index 413efef73b79951c627e6b920997fe8fd9d9c33a..b6e02569d2a34168bf4491716c45ebc0d2b6ee14 100644
--- a/lib/connector/sabre/directory.php
+++ b/lib/connector/sabre/directory.php
@@ -200,7 +200,7 @@ class OC_Connector_Sabre_Directory extends OC_Connector_Sabre_Node implements Sa
 	public function getProperties($properties) {
 		$props = parent::getProperties($properties);
 		if (in_array(self::GETETAG_PROPERTYNAME, $properties) && !isset($props[self::GETETAG_PROPERTYNAME])) {
-			$props[self::GETETAG_PROPERTYNAME] 
+			$props[self::GETETAG_PROPERTYNAME]
 				= OC_Connector_Sabre_Node::getETagPropertyForPath($this->path);
 		}
 		return $props;
diff --git a/lib/connector/sabre/principal.php b/lib/connector/sabre/principal.php
index ee95ae6330670968eaaa775802529f2222becabb..763503721f8225db4abe149ec1e04caec2a7a0a4 100644
--- a/lib/connector/sabre/principal.php
+++ b/lib/connector/sabre/principal.php
@@ -115,11 +115,11 @@ class OC_Connector_Sabre_Principal implements Sabre_DAVACL_IPrincipalBackend {
 	public function setGroupMemberSet($principal, array $members) {
 		throw new Sabre_DAV_Exception('Setting members of the group is not supported yet');
 	}
-	
+
 	function updatePrincipal($path, $mutations) {
 		return 0;
 	}
-	
+
 	function searchPrincipals($prefixPath, array $searchProperties) {
 		return 0;
 	}
diff --git a/lib/db.php b/lib/db.php
index 6c9eec5637d50839dd17bc6ae47f39989b863459..a43f2ad20b2fddef4b673f46794115b45ab212b0 100644
--- a/lib/db.php
+++ b/lib/db.php
@@ -476,7 +476,7 @@ class OC_DB {
 	public static function updateDbFromStructure($file) {
 		$CONFIG_DBTABLEPREFIX = OC_Config::getValue( "dbtableprefix", "oc_" );
 		$CONFIG_DBTYPE = OC_Config::getValue( "dbtype", "sqlite" );
-		
+
 		self::connectScheme();
 
 		// read file
@@ -683,7 +683,7 @@ class OC_DB {
 			return false;
 		}
 	}
-	
+
 	/**
 	 * returns the error code and message as a string for logging
 	 * works with MDB2 and PDOException
diff --git a/lib/fileproxy/fileoperations.php b/lib/fileproxy/fileoperations.php
index fe7edafad2b5c8f36e7c5dd04c3445a39a44acd1..23fb63fcfb114383631da82cb3c1d8dbb78738cc 100644
--- a/lib/fileproxy/fileoperations.php
+++ b/lib/fileproxy/fileoperations.php
@@ -1,37 +1,37 @@
 <?php
-/**
- * ownCloud
- *
- * @author Bjoern Schiessle
- * @copyright 2012 Bjoern Schiessle <schiessle@owncloud.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
- * License as published by the Free Software Foundation; either
- * version 3 of the License, or any later version.
- *
- * This library 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 along with this library.  If not, see <http://www.gnu.org/licenses/>.
- *
- */
-
-/**
- * check if standard file operations
+/**
+ * ownCloud
+ *
+ * @author Bjoern Schiessle
+ * @copyright 2012 Bjoern Schiessle <schiessle@owncloud.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This library 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 along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ *
  */
- 
-class OC_FileProxy_FileOperations extends OC_FileProxy{
-	static $rootView;
 
-	public function premkdir($path) {
-		if(!self::$rootView){
-			self::$rootView = new OC_FilesystemView('');
+/**
+ * check if standard file operations
+ */
+
+class OC_FileProxy_FileOperations extends OC_FileProxy{
+	static $rootView;
+
+	public function premkdir($path) {
+		if(!self::$rootView){
+			self::$rootView = new OC_FilesystemView('');
 		}
-		return !self::$rootView->file_exists($path);
+		return !self::$rootView->file_exists($path);
 	}
-	
+
 }
\ No newline at end of file
diff --git a/lib/image.php b/lib/image.php
index 861353e039dfd92201ffff3b94dcc1c32bf629fb..016d20599b252e45ac4499f33301ff054fe0e05f 100644
--- a/lib/image.php
+++ b/lib/image.php
@@ -669,7 +669,7 @@ class OC_Image {
 
 		$newWidth = min($maxWidth, $ratio*$maxHeight);
 		$newHeight = min($maxHeight, $maxWidth/$ratio);
-		
+
 		$this->preciseResize(round($newWidth), round($newHeight));
 		return true;
 	}
diff --git a/lib/migration/content.php b/lib/migration/content.php
index 89b1e782d86a8ee94affb55285daf1d00341151c..87f8da68c9d6c376dcdf2945821f9291e5d83bb9 100644
--- a/lib/migration/content.php
+++ b/lib/migration/content.php
@@ -48,7 +48,7 @@ class OC_Migration_Content{
 	// @brief prepares the db
 	// @param $query the sql query to prepare
 	public function prepare( $query ) {
-		
+
 		// Only add database to tmpfiles if actually used
 		if( !is_null( $this->db ) ) {
 			// Get db path
@@ -57,7 +57,7 @@ class OC_Migration_Content{
 				$this->tmpfiles[] = $db;
 			}
 		}
-		
+
 		// Optimize the query
 		$query = $this->processQuery( $query );
 
diff --git a/lib/ocsclient.php b/lib/ocsclient.php
index 794bc972f579956d51b04ed39468393a28fbabb5..3c80f319662bc223002945109f2bbee1904667e5 100644
--- a/lib/ocsclient.php
+++ b/lib/ocsclient.php
@@ -62,7 +62,7 @@ class OC_OCSClient{
 					'timeout' => 10
 				)
 			)
-		);      
+		);
 		$data=@file_get_contents($url, 0, $ctx);
 		return($data);
 	}
diff --git a/lib/public/share.php b/lib/public/share.php
index 1db3a0b2c1de80685b073936d084fe51f09bd9ae..faa44d7473556bf28e9b588f5c0727c7c6164030 100644
--- a/lib/public/share.php
+++ b/lib/public/share.php
@@ -1,1251 +1,1251 @@
-<?php
-/**
-* ownCloud
-*
-* @author Michael Gapczynski
-* @copyright 2012 Michael Gapczynski mtgap@owncloud.com
-*
-* This library is free software; you can redistribute it and/or
-* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
-* License as published by the Free Software Foundation; either
-* version 3 of the License, or any later version.
-*
-* This library 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 along with this library.  If not, see <http://www.gnu.org/licenses/>.
-*/
-namespace OCP;
-
-\OC_Hook::connect('OC_User', 'post_deleteUser', 'OCP\Share', 'post_deleteUser');
-\OC_Hook::connect('OC_User', 'post_addToGroup', 'OCP\Share', 'post_addToGroup');
-\OC_Hook::connect('OC_User', 'post_removeFromGroup', 'OCP\Share', 'post_removeFromGroup');
-\OC_Hook::connect('OC_User', 'post_deleteGroup', 'OCP\Share', 'post_deleteGroup');
-
-/**
-* This class provides the ability for apps to share their content between users.
-* Apps must create a backend class that implements OCP\Share_Backend and register it with this class.
-*/
-class Share {
-
-	const SHARE_TYPE_USER = 0;
-	const SHARE_TYPE_GROUP = 1;
-	const SHARE_TYPE_LINK = 3;
-	const SHARE_TYPE_EMAIL = 4;
-	const SHARE_TYPE_CONTACT = 5;
-	const SHARE_TYPE_REMOTE = 6;
-
-	/** CRUDS permissions (Create, Read, Update, Delete, Share) using a bitmask
-	* Construct permissions for share() and setPermissions with Or (|) e.g. Give user read and update permissions: PERMISSION_READ | PERMISSION_UPDATE
-	* Check if permission is granted with And (&) e.g. Check if delete is granted: if ($permissions & PERMISSION_DELETE)
-	* Remove permissions with And (&) and Not (~) e.g. Remove the update permission: $permissions &= ~PERMISSION_UPDATE
-	* Apps are required to handle permissions on their own, this class only stores and manages the permissions of shares
-	*/
-	const PERMISSION_CREATE = 4;
-	const PERMISSION_READ = 1;
-	const PERMISSION_UPDATE = 2;
-	const PERMISSION_DELETE = 8;
-	const PERMISSION_SHARE = 16;
-
-	const FORMAT_NONE = -1;
-	const FORMAT_STATUSES = -2;
-	const FORMAT_SOURCES = -3;
-
-	private static $shareTypeUserAndGroups = -1;
-	private static $shareTypeGroupUserUnique = 2;
-	private static $backends = array();
-	private static $backendTypes = array();
-
-	/**
-	* @brief Register a sharing backend class that implements OCP\Share_Backend for an item type
-	* @param string Item type
-	* @param string Backend class
-	* @param string (optional) Depends on item type
-	* @param array (optional) List of supported file extensions if this item type depends on files
-	* @return Returns true if backend is registered or false if error
-	*/
-	public static function registerBackend($itemType, $class, $collectionOf = null, $supportedFileExtensions = null) {
-		if (self::isEnabled()) {
-			if (!isset(self::$backendTypes[$itemType])) {
-				self::$backendTypes[$itemType] = array('class' => $class, 'collectionOf' => $collectionOf, 'supportedFileExtensions' => $supportedFileExtensions);
-				if(count(self::$backendTypes) === 1) {
-					\OC_Util::addScript('core', 'share');
-					\OC_Util::addStyle('core', 'share');
-				}
-				return true;
-			}
-			\OC_Log::write('OCP\Share', 'Sharing backend '.$class.' not registered, '.self::$backendTypes[$itemType]['class'].' is already registered for '.$itemType, \OC_Log::WARN);
-		}
-		return false;
-	}
-
-	/**
-	* @brief Check if the Share API is enabled
-	* @return Returns true if enabled or false
-	*
-	* The Share API is enabled by default if not configured
-	*
-	*/
-	public static function isEnabled() {
-		if (\OC_Appconfig::getValue('core', 'shareapi_enabled', 'yes') == 'yes') {
-			return true;
-		}
-		return false;
-	}
-
-	/**
-	* @brief Get the items of item type shared with the current user
-	* @param string Item type
-	* @param int Format (optional) Format type must be defined by the backend
-	* @param int Number of items to return (optional) Returns all by default
-	* @return Return depends on format
-	*/
-	public static function getItemsSharedWith($itemType, $format = self::FORMAT_NONE, $parameters = null, $limit = -1, $includeCollections = false) {
-		return self::getItems($itemType, null, self::$shareTypeUserAndGroups, \OC_User::getUser(), null, $format, $parameters, $limit, $includeCollections);
-	}
-
-	/**
-	* @brief Get the item of item type shared with the current user
-	* @param string Item type
-	* @param string Item target
-	* @param int Format (optional) Format type must be defined by the backend
-	* @return Return depends on format
-	*/
-	public static function getItemSharedWith($itemType, $itemTarget, $format = self::FORMAT_NONE, $parameters = null, $includeCollections = false) {
-		return self::getItems($itemType, $itemTarget, self::$shareTypeUserAndGroups, \OC_User::getUser(), null, $format, $parameters, 1, $includeCollections);
-	}
-
-	/**
-	* @brief Get the item of item type shared with the current user by source
-	* @param string Item type
-	* @param string Item source
-	* @param int Format (optional) Format type must be defined by the backend
-	* @return Return depends on format
-	*/
-	public static function getItemSharedWithBySource($itemType, $itemSource, $format = self::FORMAT_NONE, $parameters = null, $includeCollections = false) {
-		return self::getItems($itemType, $itemSource, self::$shareTypeUserAndGroups, \OC_User::getUser(), null, $format, $parameters, 1, $includeCollections, true);
-	}
-
-	/**
-	* @brief Get the item of item type shared by a link
-	* @param string Item type
-	* @param string Item source
-	* @param string Owner of link
-	* @return Item
-	*/
-	public static function getItemSharedWithByLink($itemType, $itemSource, $uidOwner) {
-		return self::getItems($itemType, $itemSource, self::SHARE_TYPE_LINK, null, $uidOwner, self::FORMAT_NONE, null, 1);
-	}
-
-	/**
-	* @brief Get the shared items of item type owned by the current user
-	* @param string Item type
-	* @param int Format (optional) Format type must be defined by the backend
-	* @param int Number of items to return (optional) Returns all by default
-	* @return Return depends on format
-	*/
-	public static function getItemsShared($itemType, $format = self::FORMAT_NONE, $parameters = null, $limit = -1, $includeCollections = false) {
-		return self::getItems($itemType, null, null, null, \OC_User::getUser(), $format, $parameters, $limit, $includeCollections);
-	}
-
-	/**
-	* @brief Get the shared item of item type owned by the current user
-	* @param string Item type
-	* @param string Item source
-	* @param int Format (optional) Format type must be defined by the backend
-	* @return Return depends on format
-	*/
-	public static function getItemShared($itemType, $itemSource, $format = self::FORMAT_NONE, $parameters = null, $includeCollections = false) {
-		return self::getItems($itemType, $itemSource, null, null, \OC_User::getUser(), $format, $parameters, -1, $includeCollections);
-	}
-
-	/**
-	* @brief Share an item with a user, group, or via private link
-	* @param string Item type
-	* @param string Item source
-	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
-	* @param string User or group the item is being shared with
-	* @param int CRUDS permissions
-	* @return bool Returns true on success or false on failure
-	*/
-	public static function shareItem($itemType, $itemSource, $shareType, $shareWith, $permissions) {
-		$uidOwner = \OC_User::getUser();
-		$sharingPolicy = \OC_Appconfig::getValue('core', 'shareapi_share_policy', 'global');
-		// Verify share type and sharing conditions are met
-		if ($shareType === self::SHARE_TYPE_USER) {
-			if ($shareWith == $uidOwner) {
-				$message = 'Sharing '.$itemSource.' failed, because the user '.$shareWith.' is the item owner';
-				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-				throw new \Exception($message);
-			}
-			if (!\OC_User::userExists($shareWith)) {
-				$message = 'Sharing '.$itemSource.' failed, because the user '.$shareWith.' does not exist';
-				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-				throw new \Exception($message);
-			}
-			if ($sharingPolicy == 'groups_only') {
-				$inGroup = array_intersect(\OC_Group::getUserGroups($uidOwner), \OC_Group::getUserGroups($shareWith));
-				if (empty($inGroup)) {
-					$message = 'Sharing '.$itemSource.' failed, because the user '.$shareWith.' is not a member of any groups that '.$uidOwner.' is a member of';
-					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-					throw new \Exception($message);
-				}
-			}
-			// Check if the item source is already shared with the user, either from the same owner or a different user
-			if ($checkExists = self::getItems($itemType, $itemSource, self::$shareTypeUserAndGroups, $shareWith, null, self::FORMAT_NONE, null, 1, true, true)) {
-				// Only allow the same share to occur again if it is the same owner and is not a user share, this use case is for increasing permissions for a specific user
-				if ($checkExists['uid_owner'] != $uidOwner || $checkExists['share_type'] == $shareType) {
-					$message = 'Sharing '.$itemSource.' failed, because this item is already shared with '.$shareWith;
-					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-					throw new \Exception($message);
-				}
-			}
-		} else if ($shareType === self::SHARE_TYPE_GROUP) {
-			if (!\OC_Group::groupExists($shareWith)) {
-				$message = 'Sharing '.$itemSource.' failed, because the group '.$shareWith.' does not exist';
-				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-				throw new \Exception($message);
-			}
-			if ($sharingPolicy == 'groups_only' && !\OC_Group::inGroup($uidOwner, $shareWith)) {
-				$message = 'Sharing '.$itemSource.' failed, because '.$uidOwner.' is not a member of the group '.$shareWith;
-				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-				throw new \Exception($message);
-			}
-			// Check if the item source is already shared with the group, either from the same owner or a different user
-			// The check for each user in the group is done inside the put() function
-			if ($checkExists = self::getItems($itemType, $itemSource, self::SHARE_TYPE_GROUP, $shareWith, null, self::FORMAT_NONE, null, 1, true, true)) {
-				// Only allow the same share to occur again if it is the same owner and is not a group share, this use case is for increasing permissions for a specific user
-				if ($checkExists['uid_owner'] != $uidOwner || $checkExists['share_type'] == $shareType) {
-					$message = 'Sharing '.$itemSource.' failed, because this item is already shared with '.$shareWith;
-					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-					throw new \Exception($message);
-				}
-			}
-			// Convert share with into an array with the keys group and users
-			$group = $shareWith;
-			$shareWith = array();
-			$shareWith['group'] = $group;
-			$shareWith['users'] = array_diff(\OC_Group::usersInGroup($group), array($uidOwner));
-		} else if ($shareType === self::SHARE_TYPE_LINK) {
-			if (\OC_Appconfig::getValue('core', 'shareapi_allow_links', 'yes') == 'yes') {
-				if ($checkExists = self::getItems($itemType, $itemSource, self::SHARE_TYPE_LINK, null, $uidOwner, self::FORMAT_NONE, null, 1)) {
-					// If password is set delete the old link
-					if (isset($shareWith)) {
-						self::delete($checkExists['id']);
-					} else {
-						$message = 'Sharing '.$itemSource.' failed, because this item is already shared with a link';
-						\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-						throw new \Exception($message);
-					}
-				}
-				// Generate hash of password - same method as user passwords
-				if (isset($shareWith)) {
-					$forcePortable = (CRYPT_BLOWFISH != 1);
-					$hasher = new \PasswordHash(8, $forcePortable);
-					$shareWith = $hasher->HashPassword($shareWith.\OC_Config::getValue('passwordsalt', ''));
-				}
-				return self::put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions);
-			}
-			$message = 'Sharing '.$itemSource.' failed, because sharing with links is not allowed';
-			\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-			throw new \Exception($message);
-			return false;
-// 		} else if ($shareType === self::SHARE_TYPE_CONTACT) {
-// 			if (!\OC_App::isEnabled('contacts')) {
-// 				$message = 'Sharing '.$itemSource.' failed, because the contacts app is not enabled';
-// 				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-// 				return false;
-// 			}
-// 			$vcard = \OC_Contacts_App::getContactVCard($shareWith);
-// 			if (!isset($vcard)) {
-// 				$message = 'Sharing '.$itemSource.' failed, because the contact does not exist';
-// 				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-// 				throw new \Exception($message);
-// 			}
-// 			$details = \OC_Contacts_VCard::structureContact($vcard);
-// 			// TODO Add ownCloud user to contacts vcard
-// 			if (!isset($details['EMAIL'])) {
-// 				$message = 'Sharing '.$itemSource.' failed, because no email address is associated with the contact';
-// 				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-// 				throw new \Exception($message);
-// 			}
-// 			return self::shareItem($itemType, $itemSource, self::SHARE_TYPE_EMAIL, $details['EMAIL'], $permissions);
-		} else {
-			// Future share types need to include their own conditions
-			$message = 'Share type '.$shareType.' is not valid for '.$itemSource;
-			\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-			throw new \Exception($message);
-		}
-		// If the item is a folder, scan through the folder looking for equivalent item types
-		if ($itemType == 'folder') {
-			$parentFolder = self::put('folder', $itemSource, $shareType, $shareWith, $uidOwner, $permissions, true);
-			if ($parentFolder && $files = \OC_Files::getDirectoryContent($itemSource)) {
-				for ($i = 0; $i < count($files); $i++) {
-					$name = substr($files[$i]['name'], strpos($files[$i]['name'], $itemSource) - strlen($itemSource));
-					if ($files[$i]['mimetype'] == 'httpd/unix-directory' && $children = \OC_Files::getDirectoryContent($name, '/')) {
-						// Continue scanning into child folders
-						array_push($files, $children);
-					} else {
-						// Check file extension for an equivalent item type to convert to
-						$extension = strtolower(substr($itemSource, strrpos($itemSource, '.') + 1));
-						foreach (self::$backends as $type => $backend) {
-							if (isset($backend->dependsOn) && $backend->dependsOn == 'file' && isset($backend->supportedFileExtensions) && in_array($extension, $backend->supportedFileExtensions)) {
-								$itemType = $type;
-								break;
-							}
-						}
-						// Pass on to put() to check if this item should be converted, the item won't be inserted into the database unless it can be converted
-						self::put($itemType, $name, $shareType, $shareWith, $uidOwner, $permissions, $parentFolder);
-					}
-				}
-				return true;
-			}
-			return false;
-		} else {
-			// Put the item into the database
-			return self::put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions);
-		}
-	}
-
-	/**
-	* @brief Unshare an item from a user, group, or delete a private link
-	* @param string Item type
-	* @param string Item source
-	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
-	* @param string User or group the item is being shared with
-	* @return Returns true on success or false on failure
-	*/
-	public static function unshare($itemType, $itemSource, $shareType, $shareWith) {
-		if ($item = self::getItems($itemType, $itemSource, $shareType, $shareWith, \OC_User::getUser(), self::FORMAT_NONE, null, 1)) {
-			self::delete($item['id']);
-			return true;
-		}
-		return false;
-	}
-
-	/**
-	* @brief Unshare an item shared with the current user
-	* @param string Item type
-	* @param string Item target
-	* @return Returns true on success or false on failure
-	*
-	* Unsharing from self is not allowed for items inside collections
-	*
-	*/
-	public static function unshareFromSelf($itemType, $itemTarget) {
-		if ($item = self::getItemSharedWith($itemType, $itemTarget)) {
-			if ((int)$item['share_type'] === self::SHARE_TYPE_GROUP) {
-				// Insert an extra row for the group share and set permission to 0 to prevent it from showing up for the user
-				$query = \OC_DB::prepare('INSERT INTO `*PREFIX*share` (`item_type`, `item_source`, `item_target`, `parent`, `share_type`, `share_with`, `uid_owner`, `permissions`, `stime`, `file_source`, `file_target`) VALUES (?,?,?,?,?,?,?,?,?,?,?)');
-				$query->execute(array($item['item_type'], $item['item_source'], $item['item_target'], $item['id'], self::$shareTypeGroupUserUnique, \OC_User::getUser(), $item['uid_owner'], 0, $item['stime'], $item['file_source'], $item['file_target']));
-				\OC_DB::insertid('*PREFIX*share');
-				// Delete all reshares by this user of the group share
-				self::delete($item['id'], true, \OC_User::getUser());
-			} else if ((int)$item['share_type'] === self::$shareTypeGroupUserUnique) {
-				// Set permission to 0 to prevent it from showing up for the user
-				$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `permissions` = ? WHERE `id` = ?');
-				$query->execute(array(0, $item['id']));
-				self::delete($item['id'], true);
-			} else {
-				self::delete($item['id']);
-			}
-			return true;
-		}
-		return false;
-	}
-
-	/**
-	* @brief Set the permissions of an item for a specific user or group
-	* @param string Item type
-	* @param string Item source
-	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
-	* @param string User or group the item is being shared with
-	* @param int CRUDS permissions
-	* @return Returns true on success or false on failure
-	*/
-	public static function setPermissions($itemType, $itemSource, $shareType, $shareWith, $permissions) {
-		if ($item = self::getItems($itemType, $itemSource, $shareType, $shareWith, \OC_User::getUser(), self::FORMAT_NONE, null, 1, false)) {
-			// Check if this item is a reshare and verify that the permissions granted don't exceed the parent shared item
-			if (isset($item['parent'])) {
-				$query = \OC_DB::prepare('SELECT `permissions` FROM `*PREFIX*share` WHERE `id` = ?', 1);
-				$result = $query->execute(array($item['parent']))->fetchRow();
-				if (~(int)$result['permissions'] & $permissions) {
-					$message = 'Setting permissions for '.$itemSource.' failed, because the permissions exceed permissions granted to '.\OC_User::getUser();
-					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-					throw new \Exception($message);
-				}
-			}
-			$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `permissions` = ? WHERE `id` = ?');
-			$query->execute(array($permissions, $item['id']));
-			// Check if permissions were removed
-			if ($item['permissions'] & ~$permissions) {
-				// If share permission is removed all reshares must be deleted
-				if (($item['permissions'] & self::PERMISSION_SHARE) && (~$permissions & self::PERMISSION_SHARE)) {
-					self::delete($item['id'], true);
-				} else {
-					$ids = array();
-					$parents = array($item['id']);
-					while (!empty($parents)) {
-						$parents = "'".implode("','", $parents)."'";
-						$query = \OC_DB::prepare('SELECT `id`, `permissions` FROM `*PREFIX*share` WHERE `parent` IN ('.$parents.')');
-						$result = $query->execute();
-						// Reset parents array, only go through loop again if items are found that need permissions removed
-						$parents = array();
-						while ($item = $result->fetchRow()) {
-							// Check if permissions need to be removed
-							if ($item['permissions'] & ~$permissions) {
-								// Add to list of items that need permissions removed
-								$ids[] = $item['id'];
-								$parents[] = $item['id'];
-							}
-						}
-					}
-					// Remove the permissions for all reshares of this item
-					if (!empty($ids)) {
-						$ids = "'".implode("','", $ids)."'";
-						$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `permissions` = `permissions` & ? WHERE `id` IN ('.$ids.')');
-						$query->execute(array($permissions));
-					}
-				}
-			}
-			return true;
-		}
-		$message = 'Setting permissions for '.$itemSource.' failed, because the item was not found';
-		\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-		throw new \Exception($message);
-	}
-
-	public static function setExpirationDate($itemType, $itemSource, $date) {
-		if ($items = self::getItems($itemType, $itemSource, null, null, \OC_User::getUser(), self::FORMAT_NONE, null, -1, false)) {
-			if (!empty($items)) {
-				if ($date == '') {
-					$date = null;
-				} else {
-					$date = new \DateTime($date);
-					$date = date('Y-m-d H:i', $date->format('U') - $date->getOffset());
-				}
-				$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `expiration` = ? WHERE `id` = ?');
-				foreach ($items as $item) {
-					$query->execute(array($date, $item['id']));
-				}
-				return true;
-			}
-		}
-		return false;
-	}
-
-	/**
-	* @brief Get the backend class for the specified item type
-	* @param string Item type
-	* @return Sharing backend object
-	*/
-	private static function getBackend($itemType) {
-		if (isset(self::$backends[$itemType])) {
-			return self::$backends[$itemType];
-		} else if (isset(self::$backendTypes[$itemType]['class'])) {
-			$class = self::$backendTypes[$itemType]['class'];
-			if (class_exists($class)) {
-				self::$backends[$itemType] = new $class;
-				if (!(self::$backends[$itemType] instanceof Share_Backend)) {
-					$message = 'Sharing backend '.$class.' must implement the interface OCP\Share_Backend';
-					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-					throw new \Exception($message);
-				}
-				return self::$backends[$itemType];
-			} else {
-				$message = 'Sharing backend '.$class.' not found';
-				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-				throw new \Exception($message);
-			}
-		}
-		$message = 'Sharing backend for '.$itemType.' not found';
-		\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-		throw new \Exception($message);
-	}
-
-	/**
-	* @brief Get a list of collection item types for the specified item type
-	* @param string Item type
-	* @return array
-	*/
-	private static function getCollectionItemTypes($itemType) {
-		$collectionTypes = array($itemType);
-		foreach (self::$backendTypes as $type => $backend) {
-			if (in_array($backend['collectionOf'], $collectionTypes)) {
-				$collectionTypes[] = $type;
-			}
-		}
-		if (!self::getBackend($itemType) instanceof Share_Backend_Collection) {
-			unset($collectionTypes[0]);
-		}
-		// Return array if collections were found or the item type is a collection itself - collections can be inside collections
-		if (count($collectionTypes) > 0) {
-			return $collectionTypes;
-		}
-		return false;
-	}
-
-	/**
-	* @brief Get shared items from the database
-	* @param string Item type
-	* @param string Item source or target (optional)
-	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, SHARE_TYPE_LINK, $shareTypeUserAndGroups, or $shareTypeGroupUserUnique
-	* @param string User or group the item is being shared with
-	* @param string User that is the owner of shared items (optional)
-	* @param int Format to convert items to with formatItems()
-	* @param mixed Parameters to pass to formatItems()
-	* @param int Number of items to return, -1 to return all matches (optional)
-	* @param bool Include collection item types (optional)
-	* @return mixed
-	*
-	* See public functions getItem(s)... for parameter usage
-	*
-	*/
-	private static function getItems($itemType, $item = null, $shareType = null, $shareWith = null, $uidOwner = null, $format = self::FORMAT_NONE, $parameters = null, $limit = -1, $includeCollections = false, $itemShareWithBySource = false) {
-		if (!self::isEnabled()) {
-			if ($limit == 1 || (isset($uidOwner) && isset($item))) {
-				return false;
-			} else {
-				return array();
-			}
-		}
-		$backend = self::getBackend($itemType);
-		// Get filesystem root to add it to the file target and remove from the file source, match file_source with the file cache
-		if ($itemType == 'file' || $itemType == 'folder') {
-			$root = \OC_Filesystem::getRoot();
-			$where = 'INNER JOIN `*PREFIX*fscache` ON `file_source` = `*PREFIX*fscache`.`id`';
-			if (!isset($item)) {
-				$where .= ' WHERE `file_target` IS NOT NULL';
-			}
-			$fileDependent = true;
-			$queryArgs = array();
-		} else {
-			$fileDependent = false;
-			$root = '';
-			if ($includeCollections && !isset($item) && ($collectionTypes = self::getCollectionItemTypes($itemType))) {
-				// If includeCollections is true, find collections of this item type, e.g. a music album contains songs
-				if (!in_array($itemType, $collectionTypes)) {
-					$itemTypes = array_merge(array($itemType), $collectionTypes);
-				} else {
-					$itemTypes = $collectionTypes;
-				}
-				$placeholders = join(',', array_fill(0, count($itemTypes), '?'));
-				$where .= ' WHERE item_type IN ('.$placeholders.'))';
-				$queryArgs = $itemTypes;
-			} else {
-				$where = ' WHERE `item_type` = ?';
-				$queryArgs = array($itemType);
-			}
-		}
-		if (isset($shareType)) {
-			// Include all user and group items
-			if ($shareType == self::$shareTypeUserAndGroups && isset($shareWith)) {
-				$where .= ' AND `share_type` IN (?,?,?)';
-				$queryArgs[] = self::SHARE_TYPE_USER;
-				$queryArgs[] = self::SHARE_TYPE_GROUP;
-				$queryArgs[] = self::$shareTypeGroupUserUnique;
-				$userAndGroups = array_merge(array($shareWith), \OC_Group::getUserGroups($shareWith));
-				$placeholders = join(',', array_fill(0, count($userAndGroups), '?'));
-				$where .= ' AND `share_with` IN ('.$placeholders.')';
-				$queryArgs = array_merge($queryArgs, $userAndGroups);
-				// Don't include own group shares
-				$where .= ' AND `uid_owner` != ?';
-				$queryArgs[] = $shareWith;
-			} else {
-				$where .= ' AND `share_type` = ?';
-				$queryArgs[] = $shareType;
-				if (isset($shareWith)) {
-					$where .= ' AND `share_with` = ?';
-					$queryArgs[] = $shareWith;
-				}
-			}
-		}
-		if (isset($uidOwner)) {
-			$where .= ' AND `uid_owner` = ?';
-			$queryArgs[] = $uidOwner;
-			if (!isset($shareType)) {
-				// Prevent unique user targets for group shares from being selected
-				$where .= ' AND `share_type` != ?';
-				$queryArgs[] = self::$shareTypeGroupUserUnique;
-			}
-			if ($itemType == 'file' || $itemType == 'folder') {
-				$column = 'file_source';
-			} else {
-				$column = 'item_source';
-			}
-		} else {
-			if ($itemType == 'file' || $itemType == 'folder') {
-				$column = 'file_target';
-			} else {
-				$column = 'item_target';
-			}
-		}
-		if (isset($item)) {
-			if ($includeCollections && $collectionTypes = self::getCollectionItemTypes($itemType)) {
-				$where .= ' AND (';
-			} else {
-				$where .= ' AND';
-			}
-			// If looking for own shared items, check item_source else check item_target
-			if (isset($uidOwner) || $itemShareWithBySource) {
-				// If item type is a file, file source needs to be checked in case the item was converted
-				if ($itemType == 'file' || $itemType == 'folder') {
-					$where .= ' `file_source` = ?';
-					$column = 'file_source';
-				} else {
-					$where .= ' `item_source` = ?';
-					$column = 'item_source';
-				}
-			} else {
-				if ($itemType == 'file' || $itemType == 'folder') {
-					$where .= ' `file_target` = ?';
-					$item = \OC_Filesystem::normalizePath($item);
-				} else {
-					$where .= ' `item_target` = ?';
-				}
-			}
-			$queryArgs[] = $item;
-			if ($includeCollections && $collectionTypes) {
-				$placeholders = join(',', array_fill(0, count($collectionTypes), '?'));
-				$where .= ' OR item_type IN ('.$placeholders.'))';
-				$queryArgs = array_merge($queryArgs, $collectionTypes);
-			}
-		}
-		if ($limit != -1 && !$includeCollections) {
-			if ($shareType == self::$shareTypeUserAndGroups) {
-				// Make sure the unique user target is returned if it exists, unique targets should follow the group share in the database
-				// If the limit is not 1, the filtering can be done later
-				$where .= ' ORDER BY `*PREFIX*share`.`id` DESC';
-			}
-			// The limit must be at least 3, because filtering needs to be done
-			if ($limit < 3) {
-				$queryLimit = 3;
-			} else {
-				$queryLimit = $limit;
-			}
-		} else {
-			$queryLimit = null;
-		}
-		// TODO Optimize selects
-		if ($format == self::FORMAT_STATUSES) {
-			if ($itemType == 'file' || $itemType == 'folder') {
-				$select = '`*PREFIX*share`.`id`, `item_type`, `*PREFIX*share`.`parent`, `share_type`, `file_source`, `path`, `expiration`';
-			} else {
-				$select = '`id`, `item_type`, `item_source`, `parent`, `share_type`, `expiration`';
-			}
-		} else {
-			if (isset($uidOwner)) {
-				if ($itemType == 'file' || $itemType == 'folder') {
-					$select = '`*PREFIX*share`.`id`, `item_type`, `*PREFIX*share`.`parent`, `share_type`, `share_with`, `file_source`, `path`, `permissions`, `stime`, `expiration`';
-				} else {
-					$select = '`id`, `item_type`, `item_source`, `parent`, `share_type`, `share_with`, `permissions`, `stime`, `file_source`, `expiration`';
-				}
-			} else {
-				if ($fileDependent) {
-					if (($itemType == 'file' || $itemType == 'folder') && $format == \OC_Share_Backend_File::FORMAT_FILE_APP || $format == \OC_Share_Backend_File::FORMAT_FILE_APP_ROOT) {
-						$select = '`*PREFIX*share`.`id`, `item_type`, `*PREFIX*share`.`parent`, `uid_owner`, `share_type`, `share_with`, `file_source`, `path`, `file_target`, `permissions`, `expiration`, `name`, `ctime`, `mtime`, `mimetype`, `size`, `encrypted`, `versioned`, `writable`';
-					} else {
-						$select = '`*PREFIX*share`.`id`, `item_type`, `item_source`, `item_target`, `*PREFIX*share`.`parent`, `share_type`, `share_with`, `uid_owner`, `file_source`, `path`, `file_target`, `permissions`, `stime`, `expiration`';
-					}
-				} else {
-					$select = '*';
-				}
-			}
-		}
-		$root = strlen($root);
-		$query = \OC_DB::prepare('SELECT '.$select.' FROM `*PREFIX*share` '.$where, $queryLimit);
-		$result = $query->execute($queryArgs);
-		$items = array();
-		$targets = array();
-		while ($row = $result->fetchRow()) {
-			// Filter out duplicate group shares for users with unique targets
-			if ($row['share_type'] == self::$shareTypeGroupUserUnique && isset($items[$row['parent']])) {
-				$row['share_type'] = self::SHARE_TYPE_GROUP;
-				$row['share_with'] = $items[$row['parent']]['share_with'];
-				// Remove the parent group share
-				unset($items[$row['parent']]);
-				if ($row['permissions'] == 0) {
-					continue;
-				}
-			} else if (!isset($uidOwner)) {
-				// Check if the same target already exists
-				if (isset($targets[$row[$column]])) {
-					// Check if the same owner shared with the user twice through a group and user share - this is allowed
-					$id = $targets[$row[$column]];
-					if ($items[$id]['uid_owner'] == $row['uid_owner']) {
-						// Switch to group share type to ensure resharing conditions aren't bypassed
-						if ($items[$id]['share_type'] != self::SHARE_TYPE_GROUP) {
-							$items[$id]['share_type'] = self::SHARE_TYPE_GROUP;
-							$items[$id]['share_with'] = $row['share_with'];
-						}
-						// Switch ids if sharing permission is granted on only one share to ensure correct parent is used if resharing
-						if (~(int)$items[$id]['permissions'] & self::PERMISSION_SHARE && (int)$row['permissions'] & self::PERMISSION_SHARE) {
-							$items[$row['id']] = $items[$id];
-							unset($items[$id]);
-							$id = $row['id'];
-						}
-						// Combine the permissions for the item
-						$items[$id]['permissions'] |= (int)$row['permissions'];
-						continue;
-					}
-				} else {
-					$targets[$row[$column]] = $row['id'];
-				}
-			}
-			// Remove root from file source paths if retrieving own shared items
-			if (isset($uidOwner) && isset($row['path'])) {
-				if (isset($row['parent'])) {
-					$row['path'] = '/Shared/'.basename($row['path']);
-				} else {
-					$row['path'] = substr($row['path'], $root);
-				}
-			}
-			if (isset($row['expiration'])) {
-				$time = new \DateTime();
-				if ($row['expiration'] < date('Y-m-d H:i', $time->format('U') - $time->getOffset())) {
-					self::delete($row['id']);
-					continue;
-				}
-			}
-			$items[$row['id']] = $row;
-		}
-		if (!empty($items)) {
-			$collectionItems = array();
-			foreach ($items as &$row) {
-				// Return only the item instead of a 2-dimensional array
-				if ($limit == 1 && $row['item_type'] == $itemType && $row[$column] == $item) {
-					if ($format == self::FORMAT_NONE) {
-						return $row;
-					} else {
-						break;
-					}
-				}
-				// Check if this is a collection of the requested item type
-				if ($includeCollections && $collectionTypes && in_array($row['item_type'], $collectionTypes)) {
-					if (($collectionBackend = self::getBackend($row['item_type'])) && $collectionBackend instanceof Share_Backend_Collection) {
-						// Collections can be inside collections, check if the item is a collection
-						if (isset($item) && $row['item_type'] == $itemType && $row[$column] == $item) {
-							$collectionItems[] = $row;
-						} else {
-							$collection = array();
-							$collection['item_type'] = $row['item_type'];
-							if ($row['item_type'] == 'file' || $row['item_type'] == 'folder') {
-								$collection['path'] = basename($row['path']);
-							}
-							$row['collection'] = $collection;
-							// Fetch all of the children sources
-							$children = $collectionBackend->getChildren($row[$column]);
-							foreach ($children as $child) {
-								$childItem = $row;
-								$childItem['item_type'] = $itemType;
-								if ($row['item_type'] != 'file' && $row['item_type'] != 'folder') {
-									$childItem['item_source'] = $child['source'];
-									$childItem['item_target'] = $child['target'];
-								}
-								if ($backend instanceof Share_Backend_File_Dependent) {
-									if ($row['item_type'] == 'file' || $row['item_type'] == 'folder') {
-										$childItem['file_source'] = $child['source'];
-									} else {
-										$childItem['file_source'] = \OC_FileCache::getId($child['file_path']);
-									}
-									$childItem['file_target'] = \OC_Filesystem::normalizePath($child['file_path']);
-								}
-								if (isset($item)) {
-									if ($childItem[$column] == $item) {
-										// Return only the item instead of a 2-dimensional array
-										if ($limit == 1) {
-											if ($format == self::FORMAT_NONE) {
-												return $childItem;
-											} else {
-												// Unset the items array and break out of both loops
-												$items = array();
-												$items[] = $childItem;
-												break 2;
-											}
-										} else {
-											$collectionItems[] = $childItem;
-										}
-									}
-								} else {
-									$collectionItems[] = $childItem;
-								}
-							}
-						}
-					}
-					// Remove collection item
-					unset($items[$row['id']]);
-				}
-			}
-			if (!empty($collectionItems)) {
-				$items = array_merge($items, $collectionItems);
-			}
-			if ($format == self::FORMAT_NONE) {
-				return $items;
-			} else if ($format == self::FORMAT_STATUSES) {
-				$statuses = array();
-				// Switch column to path for files and folders, used for determining statuses inside of folders
-				if ($itemType == 'file' || $itemType == 'folder') {
-					$column = 'path';
-				}
-				foreach ($items as $item) {
-					if ($item['share_type'] == self::SHARE_TYPE_LINK) {
-						$statuses[$item[$column]] = true;
-					} else if (!isset($statuses[$item[$column]])) {
-						$statuses[$item[$column]] = false;
-					}
-				}
-				return $statuses;
-			} else {
-				return $backend->formatItems($items, $format, $parameters);
-			}
-		} else if ($limit == 1 || (isset($uidOwner) && isset($item))) {
-			return false;
-		}
-		return array();
-	}
-
-	/**
-	* @brief Put shared item into the database
-	* @param string Item type
-	* @param string Item source
-	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
-	* @param string User or group the item is being shared with
-	* @param int CRUDS permissions
-	* @param bool|array Parent folder target (optional)
-	* @return bool Returns true on success or false on failure
-	*/
-	private static function put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, $parentFolder = null) {
-		$backend = self::getBackend($itemType);
-		// Check if this is a reshare
-		if ($checkReshare = self::getItemSharedWithBySource($itemType, $itemSource, self::FORMAT_NONE, null, true)) {
-			// Check if attempting to share back to owner
-			if ($checkReshare['uid_owner'] == $shareWith && $shareType == self::SHARE_TYPE_USER) {
-				$message = 'Sharing '.$itemSource.' failed, because the user '.$shareWith.' is the original sharer';
-				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-				throw new \Exception($message);
-			}
-			// Check if share permissions is granted
-			if ((int)$checkReshare['permissions'] & self::PERMISSION_SHARE) {
-				if (~(int)$checkReshare['permissions'] & $permissions) {
-					$message = 'Sharing '.$itemSource.' failed, because the permissions exceed permissions granted to '.$uidOwner;
-					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-					throw new \Exception($message);
-				} else {
-					// TODO Don't check if inside folder
-					$parent = $checkReshare['id'];
-					$itemSource = $checkReshare['item_source'];
-					$fileSource = $checkReshare['file_source'];
-					$suggestedItemTarget = $checkReshare['item_target'];
-					$suggestedFileTarget = $checkReshare['file_target'];
-					$filePath = $checkReshare['file_target'];
-				}
-			} else {
-				$message = 'Sharing '.$itemSource.' failed, because resharing is not allowed';
-				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-				throw new \Exception($message);
-			}
-		} else {
-			$parent = null;
-			$suggestedItemTarget = null;
-			$suggestedFileTarget = null;
-			if (!$backend->isValidSource($itemSource, $uidOwner)) {
-				$message = 'Sharing '.$itemSource.' failed, because the sharing backend for '.$itemType.' could not find its source';
-				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-				throw new \Exception($message);
-			}
-			$parent = null;
-			if ($backend instanceof Share_Backend_File_Dependent) {
-				$filePath = $backend->getFilePath($itemSource, $uidOwner);
-				if ($itemType == 'file' || $itemType == 'folder') {
-					$fileSource = $itemSource;
-				} else {
-					$fileSource = \OC_FileCache::getId($filePath);
-				}
-				if ($fileSource == -1) {
-					$message = 'Sharing '.$itemSource.' failed, because the file could not be found in the file cache';
-					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-					throw new \Exception($message);
-				}
-			} else {
-				$filePath = null;
-				$fileSource = null;
-			}
-		}
-		$query = \OC_DB::prepare('INSERT INTO `*PREFIX*share` (`item_type`, `item_source`, `item_target`, `parent`, `share_type`, `share_with`, `uid_owner`, `permissions`, `stime`, `file_source`, `file_target`) VALUES (?,?,?,?,?,?,?,?,?,?,?)');
-		// Share with a group
-		if ($shareType == self::SHARE_TYPE_GROUP) {
-			$groupItemTarget = self::generateTarget($itemType, $itemSource, $shareType, $shareWith['group'], $uidOwner, $suggestedItemTarget);
-			if (isset($fileSource)) {
-				if ($parentFolder) {
-					if ($parentFolder === true) {
-						$groupFileTarget = self::generateTarget('file', $filePath, $shareType, $shareWith['group'], $uidOwner, $suggestedFileTarget);
-						// Set group default file target for future use
-						$parentFolders[0]['folder'] = $groupFileTarget;
-					} else {
-						// Get group default file target
-						$groupFileTarget = $parentFolder[0]['folder'].$itemSource;
-						$parent = $parentFolder[0]['id'];
-					}
-				} else {
-					$groupFileTarget = self::generateTarget('file', $filePath, $shareType, $shareWith['group'], $uidOwner, $suggestedFileTarget);
-				}
-			} else {
-				$groupFileTarget = null;
-			}
-			$query->execute(array($itemType, $itemSource, $groupItemTarget, $parent, $shareType, $shareWith['group'], $uidOwner, $permissions, time(), $fileSource, $groupFileTarget));
-			// Save this id, any extra rows for this group share will need to reference it
-			$parent = \OC_DB::insertid('*PREFIX*share');
-			// Loop through all users of this group in case we need to add an extra row
-			foreach ($shareWith['users'] as $uid) {
-				$itemTarget = self::generateTarget($itemType, $itemSource, self::SHARE_TYPE_USER, $uid, $uidOwner, $suggestedItemTarget, $parent);
-				if (isset($fileSource)) {
-					if ($parentFolder) {
-						if ($parentFolder === true) {
-							$fileTarget = self::generateTarget('file', $filePath, self::SHARE_TYPE_USER, $uid, $uidOwner, $suggestedFileTarget, $parent);
-							if ($fileTarget != $groupFileTarget) {
-								$parentFolders[$uid]['folder'] = $fileTarget;
-							}
-						} else if (isset($parentFolder[$uid])) {
-							$fileTarget = $parentFolder[$uid]['folder'].$itemSource;
-							$parent = $parentFolder[$uid]['id'];
-						}
-					} else {
-						$fileTarget = self::generateTarget('file', $filePath, self::SHARE_TYPE_USER, $uid, $uidOwner, $suggestedFileTarget, $parent);
-					}
-				} else {
-					$fileTarget = null;
-				}
-				// Insert an extra row for the group share if the item or file target is unique for this user
-				if ($itemTarget != $groupItemTarget || (isset($fileSource) && $fileTarget != $groupFileTarget)) {
-					$query->execute(array($itemType, $itemSource, $itemTarget, $parent, self::$shareTypeGroupUserUnique, $uid, $uidOwner, $permissions, time(), $fileSource, $fileTarget));
-					\OC_DB::insertid('*PREFIX*share');
-				}
-			}
-			if ($parentFolder === true) {
-				// Return parent folders to preserve file target paths for potential children
-				return $parentFolders;
-			}
-		} else {
-			$itemTarget = self::generateTarget($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $suggestedItemTarget);
-			if (isset($fileSource)) {
-				if ($parentFolder) {
-					if ($parentFolder === true) {
-						$fileTarget = self::generateTarget('file', $filePath, $shareType, $shareWith, $uidOwner, $suggestedFileTarget);
-						$parentFolders['folder'] = $fileTarget;
-					} else {
-						$fileTarget = $parentFolder['folder'].$itemSource;
-						$parent = $parentFolder['id'];
-					}
-				} else {
-					$fileTarget = self::generateTarget('file', $filePath, $shareType, $shareWith, $uidOwner, $suggestedFileTarget);
-				}
-			} else {
-				$fileTarget = null;
-			}
-			$query->execute(array($itemType, $itemSource, $itemTarget, $parent, $shareType, $shareWith, $uidOwner, $permissions, time(), $fileSource, $fileTarget));
-			$id = \OC_DB::insertid('*PREFIX*share');
-			if ($parentFolder === true) {
-				$parentFolders['id'] = $id;
-				// Return parent folder to preserve file target paths for potential children
-				return $parentFolders;
-			}
-		}
-		return true;
-	}
-
-	/**
-	* @brief Generate a unique target for the item
-	* @param string Item type
-	* @param string Item source
-	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
-	* @param string User or group the item is being shared with
-	* @param string The suggested target originating from a reshare (optional)
-	* @param int The id of the parent group share (optional)
-	* @return string Item target
-	*/
-	private static function generateTarget($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $suggestedTarget = null, $groupParent = null) {
-		$backend = self::getBackend($itemType);
-		if ($shareType == self::SHARE_TYPE_LINK) {
-			if (isset($suggestedTarget)) {
-				return $suggestedTarget;
-			}
-			return $backend->generateTarget($itemSource, false);
-		} else {
-			if ($itemType == 'file' || $itemType == 'folder') {
-				$column = 'file_target';
-				$columnSource = 'file_source';
-			} else {
-				$column = 'item_target';
-				$columnSource = 'item_source';
-			}
-			if ($shareType == self::SHARE_TYPE_USER) {
-				// Share with is a user, so set share type to user and groups
-				$shareType = self::$shareTypeUserAndGroups;
-				$userAndGroups = array_merge(array($shareWith), \OC_Group::getUserGroups($shareWith));
-			} else {
-				$userAndGroups = false;
-			}
-			$exclude = null;
-			// Backend has 3 opportunities to generate a unique target
-			for ($i = 0; $i < 2; $i++) {
-				// Check if suggested target exists first
-				if ($i == 0 && isset($suggestedTarget)) {
-					$target = $suggestedTarget;
-				} else {
-					if ($shareType == self::SHARE_TYPE_GROUP) {
-						$target = $backend->generateTarget($itemSource, false, $exclude);
-					} else {
-						$target = $backend->generateTarget($itemSource, $shareWith, $exclude);
-					}
-					if (is_array($exclude) && in_array($target, $exclude)) {
-						break;
-					}
-				}
-				// Check if target already exists
-				$checkTarget = self::getItems($itemType, $target, $shareType, $shareWith);
-				if (!empty($checkTarget)) {
-					foreach ($checkTarget as $item) {
-						// Skip item if it is the group parent row
-						if (isset($groupParent) && $item['id'] == $groupParent) {
-							if (count($checkTarget) == 1) {
-								return $target;
-							} else {
-								continue;
-							}
-						}
-						if ($item['uid_owner'] == $uidOwner) {
-							if ($itemType == 'file' || $itemType == 'folder') {
-								if ($item['file_source'] == \OC_FileCache::getId($itemSource)) {
-									return $target;
-								}
-							} else if ($item['item_source'] == $itemSource) {
-								return $target;
-							}
-						}
-					}
-					if (!isset($exclude)) {
-						$exclude = array();
-					}
-					// Find similar targets to improve backend's chances to generate a unqiue target
-					if ($userAndGroups) {
-						if ($column == 'file_target') {
-							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share` WHERE `item_type` IN (\'file\', \'folder\') AND `share_type` IN (?,?,?) AND `share_with` IN (\''.implode('\',\'', $userAndGroups).'\')');
-							$result = $checkTargets->execute(array(self::SHARE_TYPE_USER, self::SHARE_TYPE_GROUP, self::$shareTypeGroupUserUnique));
-						} else {
-							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share` WHERE `item_type` = ? AND `share_type` IN (?,?,?) AND `share_with` IN (\''.implode('\',\'', $userAndGroups).'\')');
-							$result = $checkTargets->execute(array($itemType, self::SHARE_TYPE_USER, self::SHARE_TYPE_GROUP, self::$shareTypeGroupUserUnique));
-						}
-					} else {
-						if ($column == 'file_target') {
-							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share` WHERE `item_type` IN (\'file\', \'folder\') AND `share_type` = ? AND `share_with` = ?');
-							$result = $checkTargets->execute(array(self::SHARE_TYPE_GROUP, $shareWith));
-						} else {
-							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share` WHERE `item_type` = ? AND `share_type` = ? AND `share_with` = ?');
-							$result = $checkTargets->execute(array($itemType, self::SHARE_TYPE_GROUP, $shareWith));
-						}
-					}
-					while ($row = $result->fetchRow()) {
-						$exclude[] = $row[$column];
-					}
-				} else {
-					return $target;
-				}
-			}
-		}
-		$message = 'Sharing backend registered for '.$itemType.' did not generate a unique target for '.$itemSource;
-		\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-		throw new \Exception($message);
-	}
-
-	/**
-	* @brief Delete all reshares of an item
-	* @param int Id of item to delete
-	* @param bool If true, exclude the parent from the delete (optional)
-	* @param string The user that the parent was shared with (optinal)
-	*/
-	private static function delete($parent, $excludeParent = false, $uidOwner = null) {
-		$ids = array($parent);
-		$parents = array($parent);
-		while (!empty($parents)) {
-			$parents = "'".implode("','", $parents)."'";
-			// Check the owner on the first search of reshares, useful for finding and deleting the reshares by a single user of a group share
-			if (count($ids) == 1 && isset($uidOwner)) {
-				$query = \OC_DB::prepare('SELECT `id`, `uid_owner`, `item_type`, `item_target`, `parent` FROM `*PREFIX*share` WHERE `parent` IN ('.$parents.') AND `uid_owner` = ?');
-				$result = $query->execute(array($uidOwner));
-			} else {
-				$query = \OC_DB::prepare('SELECT `id`, `item_type`, `item_target`, `parent`, `uid_owner` FROM `*PREFIX*share` WHERE `parent` IN ('.$parents.')');
-				$result = $query->execute();
-			}
-			// Reset parents array, only go through loop again if items are found
-			$parents = array();
-			while ($item = $result->fetchRow()) {
-				// Search for a duplicate parent share, this occurs when an item is shared to the same user through a group and user or the same item is shared by different users
-				$userAndGroups = array_merge(array($item['uid_owner']), \OC_Group::getUserGroups($item['uid_owner']));
-				$query = \OC_DB::prepare('SELECT `id`, `permissions` FROM `*PREFIX*share` WHERE `item_type` = ? AND `item_target` = ? AND `share_type` IN (?,?,?) AND `share_with` IN (\''.implode('\',\'', $userAndGroups).'\') AND `uid_owner` != ? AND `id` != ?');
-				$duplicateParent = $query->execute(array($item['item_type'], $item['item_target'], self::SHARE_TYPE_USER, self::SHARE_TYPE_GROUP, self::$shareTypeGroupUserUnique, $item['uid_owner'], $item['parent']))->fetchRow();
-				if ($duplicateParent) {
-					// Change the parent to the other item id if share permission is granted
-					if ($duplicateParent['permissions'] & self::PERMISSION_SHARE) {
-						$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `parent` = ? WHERE `id` = ?');
-						$query->execute(array($duplicateParent['id'], $item['id']));
-						continue;
-					}
-				}
-				$ids[] = $item['id'];
-				$parents[] = $item['id'];
-			}
-		}
-		if ($excludeParent) {
-			unset($ids[0]);
-		}
-		if (!empty($ids)) {
-			$ids = "'".implode("','", $ids)."'";
-			$query = \OC_DB::prepare('DELETE FROM `*PREFIX*share` WHERE `id` IN ('.$ids.')');
-			$query->execute();
-		}
-	}
-
-	/**
-	* Hook Listeners
-	*/
-
-	public static function post_deleteUser($arguments) {
-		// Delete any items shared with the deleted user
-		$query = \OC_DB::prepare('DELETE FROM `*PREFIX*share` WHERE `share_with` = ? AND `share_type` = ? OR `share_type` = ?');
-		$result = $query->execute(array($arguments['uid'], self::SHARE_TYPE_USER, self::$shareTypeGroupUserUnique));
-		// Delete any items the deleted user shared
-		$query = \OC_DB::prepare('SELECT `id` FROM `*PREFIX*share` WHERE `uid_owner` = ?');
-		$result = $query->execute(array($arguments['uid']));
-		while ($item = $result->fetchRow()) {
-			self::delete($item['id']);
-		}
-	}
-
-	public static function post_addToGroup($arguments) {
-		// Find the group shares and check if the user needs a unique target
-		$query = \OC_DB::prepare('SELECT * FROM `*PREFIX*share` WHERE `share_type` = ? AND `share_with` = ?');
-		$result = $query->execute(array(self::SHARE_TYPE_GROUP, $arguments['gid']));
-		$query = \OC_DB::prepare('INSERT INTO `*PREFIX*share` (`item_type`, `item_source`, `item_target`, `parent`, `share_type`, `share_with`, `uid_owner`, `permissions`, `stime`, `file_source`, `file_target`) VALUES (?,?,?,?,?,?,?,?,?,?,?)');
-		while ($item = $result->fetchRow()) {
-			if ($item['item_type'] == 'file' || $item['item_type'] == 'file') {
-				$itemTarget = null;
-			} else {
-				$itemTarget = self::generateTarget($item['item_type'], $item['item_source'], self::SHARE_TYPE_USER, $arguments['uid'], $item['uid_owner'], $item['item_target'], $item['id']);
-			}
-			if (isset($item['file_source'])) {
-				$fileTarget = self::generateTarget($item['item_type'], $item['item_source'], self::SHARE_TYPE_USER, $arguments['uid'], $item['uid_owner'], $item['file_target'], $item['id']);
-			} else {
-				$fileTarget = null;
-			}
-			// Insert an extra row for the group share if the item or file target is unique for this user
-			if ($itemTarget != $item['item_target'] || $fileTarget != $item['file_target']) {
-				$query->execute(array($item['item_type'], $item['item_source'], $itemTarget, $item['id'], self::$shareTypeGroupUserUnique, $arguments['uid'], $item['uid_owner'], $item['permissions'], $item['stime'], $item['file_source'], $fileTarget));
-				\OC_DB::insertid('*PREFIX*share');
-			}
-		}
-	}
-
-	public static function post_removeFromGroup($arguments) {
-		// TODO Don't call if user deleted?
-		$query = \OC_DB::prepare('SELECT `id`, `share_type` FROM `*PREFIX*share` WHERE (`share_type` = ? AND `share_with` = ?) OR (`share_type` = ? AND `share_with` = ?)');
-		$result = $query->execute(array(self::SHARE_TYPE_GROUP, $arguments['gid'], self::$shareTypeGroupUserUnique, $arguments['uid']));
-		while ($item = $result->fetchRow()) {
-			if ($item['share_type'] == self::SHARE_TYPE_GROUP) {
-				// Delete all reshares by this user of the group share
-				self::delete($item['id'], true, $arguments['uid']);
-			} else {
-				self::delete($item['id']);
-			}
-		}
-	}
-
-	public static function post_deleteGroup($arguments) {
-		$query = \OC_DB::prepare('SELECT id FROM `*PREFIX*share` WHERE `share_type` = ? AND `share_with` = ?');
-		$result = $query->execute(array(self::SHARE_TYPE_GROUP, $arguments['gid']));
-		while ($item = $result->fetchRow()) {
-			self::delete($item['id']);
-		}
-	}
-
-}
-
-/**
-* Interface that apps must implement to share content.
-*/
-interface Share_Backend {
-
-	/**
-	* @brief Get the source of the item to be stored in the database
-	* @param string Item source
-	* @param string Owner of the item
-	* @return mixed|array|false Source
-	*
-	* Return an array if the item is file dependent, the array needs two keys: 'item' and 'file'
-	* Return false if the item does not exist for the user
-	*
-	* The formatItems() function will translate the source returned back into the item
-	*/
-	public function isValidSource($itemSource, $uidOwner);
-
-	/**
-	* @brief Get a unique name of the item for the specified user
-	* @param string Item source
-	* @param string|false User the item is being shared with
-	* @param array|null List of similar item names already existing as shared items
-	* @return string Target name
-	*
-	* This function needs to verify that the user does not already have an item with this name.
-	* If it does generate a new name e.g. name_#
-	*/
-	public function generateTarget($itemSource, $shareWith, $exclude = null);
-
-	/**
-	* @brief Converts the shared item sources back into the item in the specified format
-	* @param array Shared items
-	* @param int Format
-	* @return ?
-	*
-	* The items array is a 3-dimensional array with the item_source as the first key and the share id as the second key to an array with the share info.
-	* The key/value pairs included in the share info depend on the function originally called:
-	* If called by getItem(s)Shared: id, item_type, item, item_source, share_type, share_with, permissions, stime, file_source
-	* If called by getItem(s)SharedWith: id, item_type, item, item_source, item_target, share_type, share_with, permissions, stime, file_source, file_target
-	* This function allows the backend to control the output of shared items with custom formats.
-	* It is only called through calls to the public getItem(s)Shared(With) functions.
-	*/
-	public function formatItems($items, $format, $parameters = null);
-
-}
-
-/**
-* Interface for share backends that share content that is dependent on files.
-* Extends the Share_Backend interface.
-*/
-interface Share_Backend_File_Dependent extends Share_Backend {
-
-	/**
-	* @brief Get the file path of the item
-	* @param
-	* @param
-	* @return
-	*/
-	public function getFilePath($itemSource, $uidOwner);
-
-}
-
-/**
-* Interface for collections of of items implemented by another share backend.
-* Extends the Share_Backend interface.
-*/
-interface Share_Backend_Collection extends Share_Backend {
-
-	/**
-	* @brief Get the sources of the children of the item
-	* @param string Item source
-	* @return array Returns an array of children each inside an array with the keys: source, target, and file_path if applicable
-	*/
-	public function getChildren($itemSource);
-
-}
+<?php
+/**
+* ownCloud
+*
+* @author Michael Gapczynski
+* @copyright 2012 Michael Gapczynski mtgap@owncloud.com
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+* License as published by the Free Software Foundation; either
+* version 3 of the License, or any later version.
+*
+* This library 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 along with this library.  If not, see <http://www.gnu.org/licenses/>.
+*/
+namespace OCP;
+
+\OC_Hook::connect('OC_User', 'post_deleteUser', 'OCP\Share', 'post_deleteUser');
+\OC_Hook::connect('OC_User', 'post_addToGroup', 'OCP\Share', 'post_addToGroup');
+\OC_Hook::connect('OC_User', 'post_removeFromGroup', 'OCP\Share', 'post_removeFromGroup');
+\OC_Hook::connect('OC_User', 'post_deleteGroup', 'OCP\Share', 'post_deleteGroup');
+
+/**
+* This class provides the ability for apps to share their content between users.
+* Apps must create a backend class that implements OCP\Share_Backend and register it with this class.
+*/
+class Share {
+
+	const SHARE_TYPE_USER = 0;
+	const SHARE_TYPE_GROUP = 1;
+	const SHARE_TYPE_LINK = 3;
+	const SHARE_TYPE_EMAIL = 4;
+	const SHARE_TYPE_CONTACT = 5;
+	const SHARE_TYPE_REMOTE = 6;
+
+	/** CRUDS permissions (Create, Read, Update, Delete, Share) using a bitmask
+	* Construct permissions for share() and setPermissions with Or (|) e.g. Give user read and update permissions: PERMISSION_READ | PERMISSION_UPDATE
+	* Check if permission is granted with And (&) e.g. Check if delete is granted: if ($permissions & PERMISSION_DELETE)
+	* Remove permissions with And (&) and Not (~) e.g. Remove the update permission: $permissions &= ~PERMISSION_UPDATE
+	* Apps are required to handle permissions on their own, this class only stores and manages the permissions of shares
+	*/
+	const PERMISSION_CREATE = 4;
+	const PERMISSION_READ = 1;
+	const PERMISSION_UPDATE = 2;
+	const PERMISSION_DELETE = 8;
+	const PERMISSION_SHARE = 16;
+
+	const FORMAT_NONE = -1;
+	const FORMAT_STATUSES = -2;
+	const FORMAT_SOURCES = -3;
+
+	private static $shareTypeUserAndGroups = -1;
+	private static $shareTypeGroupUserUnique = 2;
+	private static $backends = array();
+	private static $backendTypes = array();
+
+	/**
+	* @brief Register a sharing backend class that implements OCP\Share_Backend for an item type
+	* @param string Item type
+	* @param string Backend class
+	* @param string (optional) Depends on item type
+	* @param array (optional) List of supported file extensions if this item type depends on files
+	* @return Returns true if backend is registered or false if error
+	*/
+	public static function registerBackend($itemType, $class, $collectionOf = null, $supportedFileExtensions = null) {
+		if (self::isEnabled()) {
+			if (!isset(self::$backendTypes[$itemType])) {
+				self::$backendTypes[$itemType] = array('class' => $class, 'collectionOf' => $collectionOf, 'supportedFileExtensions' => $supportedFileExtensions);
+				if(count(self::$backendTypes) === 1) {
+					\OC_Util::addScript('core', 'share');
+					\OC_Util::addStyle('core', 'share');
+				}
+				return true;
+			}
+			\OC_Log::write('OCP\Share', 'Sharing backend '.$class.' not registered, '.self::$backendTypes[$itemType]['class'].' is already registered for '.$itemType, \OC_Log::WARN);
+		}
+		return false;
+	}
+
+	/**
+	* @brief Check if the Share API is enabled
+	* @return Returns true if enabled or false
+	*
+	* The Share API is enabled by default if not configured
+	*
+	*/
+	public static function isEnabled() {
+		if (\OC_Appconfig::getValue('core', 'shareapi_enabled', 'yes') == 'yes') {
+			return true;
+		}
+		return false;
+	}
+
+	/**
+	* @brief Get the items of item type shared with the current user
+	* @param string Item type
+	* @param int Format (optional) Format type must be defined by the backend
+	* @param int Number of items to return (optional) Returns all by default
+	* @return Return depends on format
+	*/
+	public static function getItemsSharedWith($itemType, $format = self::FORMAT_NONE, $parameters = null, $limit = -1, $includeCollections = false) {
+		return self::getItems($itemType, null, self::$shareTypeUserAndGroups, \OC_User::getUser(), null, $format, $parameters, $limit, $includeCollections);
+	}
+
+	/**
+	* @brief Get the item of item type shared with the current user
+	* @param string Item type
+	* @param string Item target
+	* @param int Format (optional) Format type must be defined by the backend
+	* @return Return depends on format
+	*/
+	public static function getItemSharedWith($itemType, $itemTarget, $format = self::FORMAT_NONE, $parameters = null, $includeCollections = false) {
+		return self::getItems($itemType, $itemTarget, self::$shareTypeUserAndGroups, \OC_User::getUser(), null, $format, $parameters, 1, $includeCollections);
+	}
+
+	/**
+	* @brief Get the item of item type shared with the current user by source
+	* @param string Item type
+	* @param string Item source
+	* @param int Format (optional) Format type must be defined by the backend
+	* @return Return depends on format
+	*/
+	public static function getItemSharedWithBySource($itemType, $itemSource, $format = self::FORMAT_NONE, $parameters = null, $includeCollections = false) {
+		return self::getItems($itemType, $itemSource, self::$shareTypeUserAndGroups, \OC_User::getUser(), null, $format, $parameters, 1, $includeCollections, true);
+	}
+
+	/**
+	* @brief Get the item of item type shared by a link
+	* @param string Item type
+	* @param string Item source
+	* @param string Owner of link
+	* @return Item
+	*/
+	public static function getItemSharedWithByLink($itemType, $itemSource, $uidOwner) {
+		return self::getItems($itemType, $itemSource, self::SHARE_TYPE_LINK, null, $uidOwner, self::FORMAT_NONE, null, 1);
+	}
+
+	/**
+	* @brief Get the shared items of item type owned by the current user
+	* @param string Item type
+	* @param int Format (optional) Format type must be defined by the backend
+	* @param int Number of items to return (optional) Returns all by default
+	* @return Return depends on format
+	*/
+	public static function getItemsShared($itemType, $format = self::FORMAT_NONE, $parameters = null, $limit = -1, $includeCollections = false) {
+		return self::getItems($itemType, null, null, null, \OC_User::getUser(), $format, $parameters, $limit, $includeCollections);
+	}
+
+	/**
+	* @brief Get the shared item of item type owned by the current user
+	* @param string Item type
+	* @param string Item source
+	* @param int Format (optional) Format type must be defined by the backend
+	* @return Return depends on format
+	*/
+	public static function getItemShared($itemType, $itemSource, $format = self::FORMAT_NONE, $parameters = null, $includeCollections = false) {
+		return self::getItems($itemType, $itemSource, null, null, \OC_User::getUser(), $format, $parameters, -1, $includeCollections);
+	}
+
+	/**
+	* @brief Share an item with a user, group, or via private link
+	* @param string Item type
+	* @param string Item source
+	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
+	* @param string User or group the item is being shared with
+	* @param int CRUDS permissions
+	* @return bool Returns true on success or false on failure
+	*/
+	public static function shareItem($itemType, $itemSource, $shareType, $shareWith, $permissions) {
+		$uidOwner = \OC_User::getUser();
+		$sharingPolicy = \OC_Appconfig::getValue('core', 'shareapi_share_policy', 'global');
+		// Verify share type and sharing conditions are met
+		if ($shareType === self::SHARE_TYPE_USER) {
+			if ($shareWith == $uidOwner) {
+				$message = 'Sharing '.$itemSource.' failed, because the user '.$shareWith.' is the item owner';
+				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+				throw new \Exception($message);
+			}
+			if (!\OC_User::userExists($shareWith)) {
+				$message = 'Sharing '.$itemSource.' failed, because the user '.$shareWith.' does not exist';
+				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+				throw new \Exception($message);
+			}
+			if ($sharingPolicy == 'groups_only') {
+				$inGroup = array_intersect(\OC_Group::getUserGroups($uidOwner), \OC_Group::getUserGroups($shareWith));
+				if (empty($inGroup)) {
+					$message = 'Sharing '.$itemSource.' failed, because the user '.$shareWith.' is not a member of any groups that '.$uidOwner.' is a member of';
+					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+					throw new \Exception($message);
+				}
+			}
+			// Check if the item source is already shared with the user, either from the same owner or a different user
+			if ($checkExists = self::getItems($itemType, $itemSource, self::$shareTypeUserAndGroups, $shareWith, null, self::FORMAT_NONE, null, 1, true, true)) {
+				// Only allow the same share to occur again if it is the same owner and is not a user share, this use case is for increasing permissions for a specific user
+				if ($checkExists['uid_owner'] != $uidOwner || $checkExists['share_type'] == $shareType) {
+					$message = 'Sharing '.$itemSource.' failed, because this item is already shared with '.$shareWith;
+					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+					throw new \Exception($message);
+				}
+			}
+		} else if ($shareType === self::SHARE_TYPE_GROUP) {
+			if (!\OC_Group::groupExists($shareWith)) {
+				$message = 'Sharing '.$itemSource.' failed, because the group '.$shareWith.' does not exist';
+				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+				throw new \Exception($message);
+			}
+			if ($sharingPolicy == 'groups_only' && !\OC_Group::inGroup($uidOwner, $shareWith)) {
+				$message = 'Sharing '.$itemSource.' failed, because '.$uidOwner.' is not a member of the group '.$shareWith;
+				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+				throw new \Exception($message);
+			}
+			// Check if the item source is already shared with the group, either from the same owner or a different user
+			// The check for each user in the group is done inside the put() function
+			if ($checkExists = self::getItems($itemType, $itemSource, self::SHARE_TYPE_GROUP, $shareWith, null, self::FORMAT_NONE, null, 1, true, true)) {
+				// Only allow the same share to occur again if it is the same owner and is not a group share, this use case is for increasing permissions for a specific user
+				if ($checkExists['uid_owner'] != $uidOwner || $checkExists['share_type'] == $shareType) {
+					$message = 'Sharing '.$itemSource.' failed, because this item is already shared with '.$shareWith;
+					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+					throw new \Exception($message);
+				}
+			}
+			// Convert share with into an array with the keys group and users
+			$group = $shareWith;
+			$shareWith = array();
+			$shareWith['group'] = $group;
+			$shareWith['users'] = array_diff(\OC_Group::usersInGroup($group), array($uidOwner));
+		} else if ($shareType === self::SHARE_TYPE_LINK) {
+			if (\OC_Appconfig::getValue('core', 'shareapi_allow_links', 'yes') == 'yes') {
+				if ($checkExists = self::getItems($itemType, $itemSource, self::SHARE_TYPE_LINK, null, $uidOwner, self::FORMAT_NONE, null, 1)) {
+					// If password is set delete the old link
+					if (isset($shareWith)) {
+						self::delete($checkExists['id']);
+					} else {
+						$message = 'Sharing '.$itemSource.' failed, because this item is already shared with a link';
+						\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+						throw new \Exception($message);
+					}
+				}
+				// Generate hash of password - same method as user passwords
+				if (isset($shareWith)) {
+					$forcePortable = (CRYPT_BLOWFISH != 1);
+					$hasher = new \PasswordHash(8, $forcePortable);
+					$shareWith = $hasher->HashPassword($shareWith.\OC_Config::getValue('passwordsalt', ''));
+				}
+				return self::put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions);
+			}
+			$message = 'Sharing '.$itemSource.' failed, because sharing with links is not allowed';
+			\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+			throw new \Exception($message);
+			return false;
+// 		} else if ($shareType === self::SHARE_TYPE_CONTACT) {
+// 			if (!\OC_App::isEnabled('contacts')) {
+// 				$message = 'Sharing '.$itemSource.' failed, because the contacts app is not enabled';
+// 				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+// 				return false;
+// 			}
+// 			$vcard = \OC_Contacts_App::getContactVCard($shareWith);
+// 			if (!isset($vcard)) {
+// 				$message = 'Sharing '.$itemSource.' failed, because the contact does not exist';
+// 				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+// 				throw new \Exception($message);
+// 			}
+// 			$details = \OC_Contacts_VCard::structureContact($vcard);
+// 			// TODO Add ownCloud user to contacts vcard
+// 			if (!isset($details['EMAIL'])) {
+// 				$message = 'Sharing '.$itemSource.' failed, because no email address is associated with the contact';
+// 				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+// 				throw new \Exception($message);
+// 			}
+// 			return self::shareItem($itemType, $itemSource, self::SHARE_TYPE_EMAIL, $details['EMAIL'], $permissions);
+		} else {
+			// Future share types need to include their own conditions
+			$message = 'Share type '.$shareType.' is not valid for '.$itemSource;
+			\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+			throw new \Exception($message);
+		}
+		// If the item is a folder, scan through the folder looking for equivalent item types
+		if ($itemType == 'folder') {
+			$parentFolder = self::put('folder', $itemSource, $shareType, $shareWith, $uidOwner, $permissions, true);
+			if ($parentFolder && $files = \OC_Files::getDirectoryContent($itemSource)) {
+				for ($i = 0; $i < count($files); $i++) {
+					$name = substr($files[$i]['name'], strpos($files[$i]['name'], $itemSource) - strlen($itemSource));
+					if ($files[$i]['mimetype'] == 'httpd/unix-directory' && $children = \OC_Files::getDirectoryContent($name, '/')) {
+						// Continue scanning into child folders
+						array_push($files, $children);
+					} else {
+						// Check file extension for an equivalent item type to convert to
+						$extension = strtolower(substr($itemSource, strrpos($itemSource, '.') + 1));
+						foreach (self::$backends as $type => $backend) {
+							if (isset($backend->dependsOn) && $backend->dependsOn == 'file' && isset($backend->supportedFileExtensions) && in_array($extension, $backend->supportedFileExtensions)) {
+								$itemType = $type;
+								break;
+							}
+						}
+						// Pass on to put() to check if this item should be converted, the item won't be inserted into the database unless it can be converted
+						self::put($itemType, $name, $shareType, $shareWith, $uidOwner, $permissions, $parentFolder);
+					}
+				}
+				return true;
+			}
+			return false;
+		} else {
+			// Put the item into the database
+			return self::put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions);
+		}
+	}
+
+	/**
+	* @brief Unshare an item from a user, group, or delete a private link
+	* @param string Item type
+	* @param string Item source
+	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
+	* @param string User or group the item is being shared with
+	* @return Returns true on success or false on failure
+	*/
+	public static function unshare($itemType, $itemSource, $shareType, $shareWith) {
+		if ($item = self::getItems($itemType, $itemSource, $shareType, $shareWith, \OC_User::getUser(), self::FORMAT_NONE, null, 1)) {
+			self::delete($item['id']);
+			return true;
+		}
+		return false;
+	}
+
+	/**
+	* @brief Unshare an item shared with the current user
+	* @param string Item type
+	* @param string Item target
+	* @return Returns true on success or false on failure
+	*
+	* Unsharing from self is not allowed for items inside collections
+	*
+	*/
+	public static function unshareFromSelf($itemType, $itemTarget) {
+		if ($item = self::getItemSharedWith($itemType, $itemTarget)) {
+			if ((int)$item['share_type'] === self::SHARE_TYPE_GROUP) {
+				// Insert an extra row for the group share and set permission to 0 to prevent it from showing up for the user
+				$query = \OC_DB::prepare('INSERT INTO `*PREFIX*share` (`item_type`, `item_source`, `item_target`, `parent`, `share_type`, `share_with`, `uid_owner`, `permissions`, `stime`, `file_source`, `file_target`) VALUES (?,?,?,?,?,?,?,?,?,?,?)');
+				$query->execute(array($item['item_type'], $item['item_source'], $item['item_target'], $item['id'], self::$shareTypeGroupUserUnique, \OC_User::getUser(), $item['uid_owner'], 0, $item['stime'], $item['file_source'], $item['file_target']));
+				\OC_DB::insertid('*PREFIX*share');
+				// Delete all reshares by this user of the group share
+				self::delete($item['id'], true, \OC_User::getUser());
+			} else if ((int)$item['share_type'] === self::$shareTypeGroupUserUnique) {
+				// Set permission to 0 to prevent it from showing up for the user
+				$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `permissions` = ? WHERE `id` = ?');
+				$query->execute(array(0, $item['id']));
+				self::delete($item['id'], true);
+			} else {
+				self::delete($item['id']);
+			}
+			return true;
+		}
+		return false;
+	}
+
+	/**
+	* @brief Set the permissions of an item for a specific user or group
+	* @param string Item type
+	* @param string Item source
+	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
+	* @param string User or group the item is being shared with
+	* @param int CRUDS permissions
+	* @return Returns true on success or false on failure
+	*/
+	public static function setPermissions($itemType, $itemSource, $shareType, $shareWith, $permissions) {
+		if ($item = self::getItems($itemType, $itemSource, $shareType, $shareWith, \OC_User::getUser(), self::FORMAT_NONE, null, 1, false)) {
+			// Check if this item is a reshare and verify that the permissions granted don't exceed the parent shared item
+			if (isset($item['parent'])) {
+				$query = \OC_DB::prepare('SELECT `permissions` FROM `*PREFIX*share` WHERE `id` = ?', 1);
+				$result = $query->execute(array($item['parent']))->fetchRow();
+				if (~(int)$result['permissions'] & $permissions) {
+					$message = 'Setting permissions for '.$itemSource.' failed, because the permissions exceed permissions granted to '.\OC_User::getUser();
+					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+					throw new \Exception($message);
+				}
+			}
+			$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `permissions` = ? WHERE `id` = ?');
+			$query->execute(array($permissions, $item['id']));
+			// Check if permissions were removed
+			if ($item['permissions'] & ~$permissions) {
+				// If share permission is removed all reshares must be deleted
+				if (($item['permissions'] & self::PERMISSION_SHARE) && (~$permissions & self::PERMISSION_SHARE)) {
+					self::delete($item['id'], true);
+				} else {
+					$ids = array();
+					$parents = array($item['id']);
+					while (!empty($parents)) {
+						$parents = "'".implode("','", $parents)."'";
+						$query = \OC_DB::prepare('SELECT `id`, `permissions` FROM `*PREFIX*share` WHERE `parent` IN ('.$parents.')');
+						$result = $query->execute();
+						// Reset parents array, only go through loop again if items are found that need permissions removed
+						$parents = array();
+						while ($item = $result->fetchRow()) {
+							// Check if permissions need to be removed
+							if ($item['permissions'] & ~$permissions) {
+								// Add to list of items that need permissions removed
+								$ids[] = $item['id'];
+								$parents[] = $item['id'];
+							}
+						}
+					}
+					// Remove the permissions for all reshares of this item
+					if (!empty($ids)) {
+						$ids = "'".implode("','", $ids)."'";
+						$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `permissions` = `permissions` & ? WHERE `id` IN ('.$ids.')');
+						$query->execute(array($permissions));
+					}
+				}
+			}
+			return true;
+		}
+		$message = 'Setting permissions for '.$itemSource.' failed, because the item was not found';
+		\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+		throw new \Exception($message);
+	}
+
+	public static function setExpirationDate($itemType, $itemSource, $date) {
+		if ($items = self::getItems($itemType, $itemSource, null, null, \OC_User::getUser(), self::FORMAT_NONE, null, -1, false)) {
+			if (!empty($items)) {
+				if ($date == '') {
+					$date = null;
+				} else {
+					$date = new \DateTime($date);
+					$date = date('Y-m-d H:i', $date->format('U') - $date->getOffset());
+				}
+				$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `expiration` = ? WHERE `id` = ?');
+				foreach ($items as $item) {
+					$query->execute(array($date, $item['id']));
+				}
+				return true;
+			}
+		}
+		return false;
+	}
+
+	/**
+	* @brief Get the backend class for the specified item type
+	* @param string Item type
+	* @return Sharing backend object
+	*/
+	private static function getBackend($itemType) {
+		if (isset(self::$backends[$itemType])) {
+			return self::$backends[$itemType];
+		} else if (isset(self::$backendTypes[$itemType]['class'])) {
+			$class = self::$backendTypes[$itemType]['class'];
+			if (class_exists($class)) {
+				self::$backends[$itemType] = new $class;
+				if (!(self::$backends[$itemType] instanceof Share_Backend)) {
+					$message = 'Sharing backend '.$class.' must implement the interface OCP\Share_Backend';
+					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+					throw new \Exception($message);
+				}
+				return self::$backends[$itemType];
+			} else {
+				$message = 'Sharing backend '.$class.' not found';
+				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+				throw new \Exception($message);
+			}
+		}
+		$message = 'Sharing backend for '.$itemType.' not found';
+		\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+		throw new \Exception($message);
+	}
+
+	/**
+	* @brief Get a list of collection item types for the specified item type
+	* @param string Item type
+	* @return array
+	*/
+	private static function getCollectionItemTypes($itemType) {
+		$collectionTypes = array($itemType);
+		foreach (self::$backendTypes as $type => $backend) {
+			if (in_array($backend['collectionOf'], $collectionTypes)) {
+				$collectionTypes[] = $type;
+			}
+		}
+		if (!self::getBackend($itemType) instanceof Share_Backend_Collection) {
+			unset($collectionTypes[0]);
+		}
+		// Return array if collections were found or the item type is a collection itself - collections can be inside collections
+		if (count($collectionTypes) > 0) {
+			return $collectionTypes;
+		}
+		return false;
+	}
+
+	/**
+	* @brief Get shared items from the database
+	* @param string Item type
+	* @param string Item source or target (optional)
+	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, SHARE_TYPE_LINK, $shareTypeUserAndGroups, or $shareTypeGroupUserUnique
+	* @param string User or group the item is being shared with
+	* @param string User that is the owner of shared items (optional)
+	* @param int Format to convert items to with formatItems()
+	* @param mixed Parameters to pass to formatItems()
+	* @param int Number of items to return, -1 to return all matches (optional)
+	* @param bool Include collection item types (optional)
+	* @return mixed
+	*
+	* See public functions getItem(s)... for parameter usage
+	*
+	*/
+	private static function getItems($itemType, $item = null, $shareType = null, $shareWith = null, $uidOwner = null, $format = self::FORMAT_NONE, $parameters = null, $limit = -1, $includeCollections = false, $itemShareWithBySource = false) {
+		if (!self::isEnabled()) {
+			if ($limit == 1 || (isset($uidOwner) && isset($item))) {
+				return false;
+			} else {
+				return array();
+			}
+		}
+		$backend = self::getBackend($itemType);
+		// Get filesystem root to add it to the file target and remove from the file source, match file_source with the file cache
+		if ($itemType == 'file' || $itemType == 'folder') {
+			$root = \OC_Filesystem::getRoot();
+			$where = 'INNER JOIN `*PREFIX*fscache` ON `file_source` = `*PREFIX*fscache`.`id`';
+			if (!isset($item)) {
+				$where .= ' WHERE `file_target` IS NOT NULL';
+			}
+			$fileDependent = true;
+			$queryArgs = array();
+		} else {
+			$fileDependent = false;
+			$root = '';
+			if ($includeCollections && !isset($item) && ($collectionTypes = self::getCollectionItemTypes($itemType))) {
+				// If includeCollections is true, find collections of this item type, e.g. a music album contains songs
+				if (!in_array($itemType, $collectionTypes)) {
+					$itemTypes = array_merge(array($itemType), $collectionTypes);
+				} else {
+					$itemTypes = $collectionTypes;
+				}
+				$placeholders = join(',', array_fill(0, count($itemTypes), '?'));
+				$where .= ' WHERE item_type IN ('.$placeholders.'))';
+				$queryArgs = $itemTypes;
+			} else {
+				$where = ' WHERE `item_type` = ?';
+				$queryArgs = array($itemType);
+			}
+		}
+		if (isset($shareType)) {
+			// Include all user and group items
+			if ($shareType == self::$shareTypeUserAndGroups && isset($shareWith)) {
+				$where .= ' AND `share_type` IN (?,?,?)';
+				$queryArgs[] = self::SHARE_TYPE_USER;
+				$queryArgs[] = self::SHARE_TYPE_GROUP;
+				$queryArgs[] = self::$shareTypeGroupUserUnique;
+				$userAndGroups = array_merge(array($shareWith), \OC_Group::getUserGroups($shareWith));
+				$placeholders = join(',', array_fill(0, count($userAndGroups), '?'));
+				$where .= ' AND `share_with` IN ('.$placeholders.')';
+				$queryArgs = array_merge($queryArgs, $userAndGroups);
+				// Don't include own group shares
+				$where .= ' AND `uid_owner` != ?';
+				$queryArgs[] = $shareWith;
+			} else {
+				$where .= ' AND `share_type` = ?';
+				$queryArgs[] = $shareType;
+				if (isset($shareWith)) {
+					$where .= ' AND `share_with` = ?';
+					$queryArgs[] = $shareWith;
+				}
+			}
+		}
+		if (isset($uidOwner)) {
+			$where .= ' AND `uid_owner` = ?';
+			$queryArgs[] = $uidOwner;
+			if (!isset($shareType)) {
+				// Prevent unique user targets for group shares from being selected
+				$where .= ' AND `share_type` != ?';
+				$queryArgs[] = self::$shareTypeGroupUserUnique;
+			}
+			if ($itemType == 'file' || $itemType == 'folder') {
+				$column = 'file_source';
+			} else {
+				$column = 'item_source';
+			}
+		} else {
+			if ($itemType == 'file' || $itemType == 'folder') {
+				$column = 'file_target';
+			} else {
+				$column = 'item_target';
+			}
+		}
+		if (isset($item)) {
+			if ($includeCollections && $collectionTypes = self::getCollectionItemTypes($itemType)) {
+				$where .= ' AND (';
+			} else {
+				$where .= ' AND';
+			}
+			// If looking for own shared items, check item_source else check item_target
+			if (isset($uidOwner) || $itemShareWithBySource) {
+				// If item type is a file, file source needs to be checked in case the item was converted
+				if ($itemType == 'file' || $itemType == 'folder') {
+					$where .= ' `file_source` = ?';
+					$column = 'file_source';
+				} else {
+					$where .= ' `item_source` = ?';
+					$column = 'item_source';
+				}
+			} else {
+				if ($itemType == 'file' || $itemType == 'folder') {
+					$where .= ' `file_target` = ?';
+					$item = \OC_Filesystem::normalizePath($item);
+				} else {
+					$where .= ' `item_target` = ?';
+				}
+			}
+			$queryArgs[] = $item;
+			if ($includeCollections && $collectionTypes) {
+				$placeholders = join(',', array_fill(0, count($collectionTypes), '?'));
+				$where .= ' OR item_type IN ('.$placeholders.'))';
+				$queryArgs = array_merge($queryArgs, $collectionTypes);
+			}
+		}
+		if ($limit != -1 && !$includeCollections) {
+			if ($shareType == self::$shareTypeUserAndGroups) {
+				// Make sure the unique user target is returned if it exists, unique targets should follow the group share in the database
+				// If the limit is not 1, the filtering can be done later
+				$where .= ' ORDER BY `*PREFIX*share`.`id` DESC';
+			}
+			// The limit must be at least 3, because filtering needs to be done
+			if ($limit < 3) {
+				$queryLimit = 3;
+			} else {
+				$queryLimit = $limit;
+			}
+		} else {
+			$queryLimit = null;
+		}
+		// TODO Optimize selects
+		if ($format == self::FORMAT_STATUSES) {
+			if ($itemType == 'file' || $itemType == 'folder') {
+				$select = '`*PREFIX*share`.`id`, `item_type`, `*PREFIX*share`.`parent`, `share_type`, `file_source`, `path`, `expiration`';
+			} else {
+				$select = '`id`, `item_type`, `item_source`, `parent`, `share_type`, `expiration`';
+			}
+		} else {
+			if (isset($uidOwner)) {
+				if ($itemType == 'file' || $itemType == 'folder') {
+					$select = '`*PREFIX*share`.`id`, `item_type`, `*PREFIX*share`.`parent`, `share_type`, `share_with`, `file_source`, `path`, `permissions`, `stime`, `expiration`';
+				} else {
+					$select = '`id`, `item_type`, `item_source`, `parent`, `share_type`, `share_with`, `permissions`, `stime`, `file_source`, `expiration`';
+				}
+			} else {
+				if ($fileDependent) {
+					if (($itemType == 'file' || $itemType == 'folder') && $format == \OC_Share_Backend_File::FORMAT_FILE_APP || $format == \OC_Share_Backend_File::FORMAT_FILE_APP_ROOT) {
+						$select = '`*PREFIX*share`.`id`, `item_type`, `*PREFIX*share`.`parent`, `uid_owner`, `share_type`, `share_with`, `file_source`, `path`, `file_target`, `permissions`, `expiration`, `name`, `ctime`, `mtime`, `mimetype`, `size`, `encrypted`, `versioned`, `writable`';
+					} else {
+						$select = '`*PREFIX*share`.`id`, `item_type`, `item_source`, `item_target`, `*PREFIX*share`.`parent`, `share_type`, `share_with`, `uid_owner`, `file_source`, `path`, `file_target`, `permissions`, `stime`, `expiration`';
+					}
+				} else {
+					$select = '*';
+				}
+			}
+		}
+		$root = strlen($root);
+		$query = \OC_DB::prepare('SELECT '.$select.' FROM `*PREFIX*share` '.$where, $queryLimit);
+		$result = $query->execute($queryArgs);
+		$items = array();
+		$targets = array();
+		while ($row = $result->fetchRow()) {
+			// Filter out duplicate group shares for users with unique targets
+			if ($row['share_type'] == self::$shareTypeGroupUserUnique && isset($items[$row['parent']])) {
+				$row['share_type'] = self::SHARE_TYPE_GROUP;
+				$row['share_with'] = $items[$row['parent']]['share_with'];
+				// Remove the parent group share
+				unset($items[$row['parent']]);
+				if ($row['permissions'] == 0) {
+					continue;
+				}
+			} else if (!isset($uidOwner)) {
+				// Check if the same target already exists
+				if (isset($targets[$row[$column]])) {
+					// Check if the same owner shared with the user twice through a group and user share - this is allowed
+					$id = $targets[$row[$column]];
+					if ($items[$id]['uid_owner'] == $row['uid_owner']) {
+						// Switch to group share type to ensure resharing conditions aren't bypassed
+						if ($items[$id]['share_type'] != self::SHARE_TYPE_GROUP) {
+							$items[$id]['share_type'] = self::SHARE_TYPE_GROUP;
+							$items[$id]['share_with'] = $row['share_with'];
+						}
+						// Switch ids if sharing permission is granted on only one share to ensure correct parent is used if resharing
+						if (~(int)$items[$id]['permissions'] & self::PERMISSION_SHARE && (int)$row['permissions'] & self::PERMISSION_SHARE) {
+							$items[$row['id']] = $items[$id];
+							unset($items[$id]);
+							$id = $row['id'];
+						}
+						// Combine the permissions for the item
+						$items[$id]['permissions'] |= (int)$row['permissions'];
+						continue;
+					}
+				} else {
+					$targets[$row[$column]] = $row['id'];
+				}
+			}
+			// Remove root from file source paths if retrieving own shared items
+			if (isset($uidOwner) && isset($row['path'])) {
+				if (isset($row['parent'])) {
+					$row['path'] = '/Shared/'.basename($row['path']);
+				} else {
+					$row['path'] = substr($row['path'], $root);
+				}
+			}
+			if (isset($row['expiration'])) {
+				$time = new \DateTime();
+				if ($row['expiration'] < date('Y-m-d H:i', $time->format('U') - $time->getOffset())) {
+					self::delete($row['id']);
+					continue;
+				}
+			}
+			$items[$row['id']] = $row;
+		}
+		if (!empty($items)) {
+			$collectionItems = array();
+			foreach ($items as &$row) {
+				// Return only the item instead of a 2-dimensional array
+				if ($limit == 1 && $row['item_type'] == $itemType && $row[$column] == $item) {
+					if ($format == self::FORMAT_NONE) {
+						return $row;
+					} else {
+						break;
+					}
+				}
+				// Check if this is a collection of the requested item type
+				if ($includeCollections && $collectionTypes && in_array($row['item_type'], $collectionTypes)) {
+					if (($collectionBackend = self::getBackend($row['item_type'])) && $collectionBackend instanceof Share_Backend_Collection) {
+						// Collections can be inside collections, check if the item is a collection
+						if (isset($item) && $row['item_type'] == $itemType && $row[$column] == $item) {
+							$collectionItems[] = $row;
+						} else {
+							$collection = array();
+							$collection['item_type'] = $row['item_type'];
+							if ($row['item_type'] == 'file' || $row['item_type'] == 'folder') {
+								$collection['path'] = basename($row['path']);
+							}
+							$row['collection'] = $collection;
+							// Fetch all of the children sources
+							$children = $collectionBackend->getChildren($row[$column]);
+							foreach ($children as $child) {
+								$childItem = $row;
+								$childItem['item_type'] = $itemType;
+								if ($row['item_type'] != 'file' && $row['item_type'] != 'folder') {
+									$childItem['item_source'] = $child['source'];
+									$childItem['item_target'] = $child['target'];
+								}
+								if ($backend instanceof Share_Backend_File_Dependent) {
+									if ($row['item_type'] == 'file' || $row['item_type'] == 'folder') {
+										$childItem['file_source'] = $child['source'];
+									} else {
+										$childItem['file_source'] = \OC_FileCache::getId($child['file_path']);
+									}
+									$childItem['file_target'] = \OC_Filesystem::normalizePath($child['file_path']);
+								}
+								if (isset($item)) {
+									if ($childItem[$column] == $item) {
+										// Return only the item instead of a 2-dimensional array
+										if ($limit == 1) {
+											if ($format == self::FORMAT_NONE) {
+												return $childItem;
+											} else {
+												// Unset the items array and break out of both loops
+												$items = array();
+												$items[] = $childItem;
+												break 2;
+											}
+										} else {
+											$collectionItems[] = $childItem;
+										}
+									}
+								} else {
+									$collectionItems[] = $childItem;
+								}
+							}
+						}
+					}
+					// Remove collection item
+					unset($items[$row['id']]);
+				}
+			}
+			if (!empty($collectionItems)) {
+				$items = array_merge($items, $collectionItems);
+			}
+			if ($format == self::FORMAT_NONE) {
+				return $items;
+			} else if ($format == self::FORMAT_STATUSES) {
+				$statuses = array();
+				// Switch column to path for files and folders, used for determining statuses inside of folders
+				if ($itemType == 'file' || $itemType == 'folder') {
+					$column = 'path';
+				}
+				foreach ($items as $item) {
+					if ($item['share_type'] == self::SHARE_TYPE_LINK) {
+						$statuses[$item[$column]] = true;
+					} else if (!isset($statuses[$item[$column]])) {
+						$statuses[$item[$column]] = false;
+					}
+				}
+				return $statuses;
+			} else {
+				return $backend->formatItems($items, $format, $parameters);
+			}
+		} else if ($limit == 1 || (isset($uidOwner) && isset($item))) {
+			return false;
+		}
+		return array();
+	}
+
+	/**
+	* @brief Put shared item into the database
+	* @param string Item type
+	* @param string Item source
+	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
+	* @param string User or group the item is being shared with
+	* @param int CRUDS permissions
+	* @param bool|array Parent folder target (optional)
+	* @return bool Returns true on success or false on failure
+	*/
+	private static function put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, $parentFolder = null) {
+		$backend = self::getBackend($itemType);
+		// Check if this is a reshare
+		if ($checkReshare = self::getItemSharedWithBySource($itemType, $itemSource, self::FORMAT_NONE, null, true)) {
+			// Check if attempting to share back to owner
+			if ($checkReshare['uid_owner'] == $shareWith && $shareType == self::SHARE_TYPE_USER) {
+				$message = 'Sharing '.$itemSource.' failed, because the user '.$shareWith.' is the original sharer';
+				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+				throw new \Exception($message);
+			}
+			// Check if share permissions is granted
+			if ((int)$checkReshare['permissions'] & self::PERMISSION_SHARE) {
+				if (~(int)$checkReshare['permissions'] & $permissions) {
+					$message = 'Sharing '.$itemSource.' failed, because the permissions exceed permissions granted to '.$uidOwner;
+					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+					throw new \Exception($message);
+				} else {
+					// TODO Don't check if inside folder
+					$parent = $checkReshare['id'];
+					$itemSource = $checkReshare['item_source'];
+					$fileSource = $checkReshare['file_source'];
+					$suggestedItemTarget = $checkReshare['item_target'];
+					$suggestedFileTarget = $checkReshare['file_target'];
+					$filePath = $checkReshare['file_target'];
+				}
+			} else {
+				$message = 'Sharing '.$itemSource.' failed, because resharing is not allowed';
+				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+				throw new \Exception($message);
+			}
+		} else {
+			$parent = null;
+			$suggestedItemTarget = null;
+			$suggestedFileTarget = null;
+			if (!$backend->isValidSource($itemSource, $uidOwner)) {
+				$message = 'Sharing '.$itemSource.' failed, because the sharing backend for '.$itemType.' could not find its source';
+				\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+				throw new \Exception($message);
+			}
+			$parent = null;
+			if ($backend instanceof Share_Backend_File_Dependent) {
+				$filePath = $backend->getFilePath($itemSource, $uidOwner);
+				if ($itemType == 'file' || $itemType == 'folder') {
+					$fileSource = $itemSource;
+				} else {
+					$fileSource = \OC_FileCache::getId($filePath);
+				}
+				if ($fileSource == -1) {
+					$message = 'Sharing '.$itemSource.' failed, because the file could not be found in the file cache';
+					\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+					throw new \Exception($message);
+				}
+			} else {
+				$filePath = null;
+				$fileSource = null;
+			}
+		}
+		$query = \OC_DB::prepare('INSERT INTO `*PREFIX*share` (`item_type`, `item_source`, `item_target`, `parent`, `share_type`, `share_with`, `uid_owner`, `permissions`, `stime`, `file_source`, `file_target`) VALUES (?,?,?,?,?,?,?,?,?,?,?)');
+		// Share with a group
+		if ($shareType == self::SHARE_TYPE_GROUP) {
+			$groupItemTarget = self::generateTarget($itemType, $itemSource, $shareType, $shareWith['group'], $uidOwner, $suggestedItemTarget);
+			if (isset($fileSource)) {
+				if ($parentFolder) {
+					if ($parentFolder === true) {
+						$groupFileTarget = self::generateTarget('file', $filePath, $shareType, $shareWith['group'], $uidOwner, $suggestedFileTarget);
+						// Set group default file target for future use
+						$parentFolders[0]['folder'] = $groupFileTarget;
+					} else {
+						// Get group default file target
+						$groupFileTarget = $parentFolder[0]['folder'].$itemSource;
+						$parent = $parentFolder[0]['id'];
+					}
+				} else {
+					$groupFileTarget = self::generateTarget('file', $filePath, $shareType, $shareWith['group'], $uidOwner, $suggestedFileTarget);
+				}
+			} else {
+				$groupFileTarget = null;
+			}
+			$query->execute(array($itemType, $itemSource, $groupItemTarget, $parent, $shareType, $shareWith['group'], $uidOwner, $permissions, time(), $fileSource, $groupFileTarget));
+			// Save this id, any extra rows for this group share will need to reference it
+			$parent = \OC_DB::insertid('*PREFIX*share');
+			// Loop through all users of this group in case we need to add an extra row
+			foreach ($shareWith['users'] as $uid) {
+				$itemTarget = self::generateTarget($itemType, $itemSource, self::SHARE_TYPE_USER, $uid, $uidOwner, $suggestedItemTarget, $parent);
+				if (isset($fileSource)) {
+					if ($parentFolder) {
+						if ($parentFolder === true) {
+							$fileTarget = self::generateTarget('file', $filePath, self::SHARE_TYPE_USER, $uid, $uidOwner, $suggestedFileTarget, $parent);
+							if ($fileTarget != $groupFileTarget) {
+								$parentFolders[$uid]['folder'] = $fileTarget;
+							}
+						} else if (isset($parentFolder[$uid])) {
+							$fileTarget = $parentFolder[$uid]['folder'].$itemSource;
+							$parent = $parentFolder[$uid]['id'];
+						}
+					} else {
+						$fileTarget = self::generateTarget('file', $filePath, self::SHARE_TYPE_USER, $uid, $uidOwner, $suggestedFileTarget, $parent);
+					}
+				} else {
+					$fileTarget = null;
+				}
+				// Insert an extra row for the group share if the item or file target is unique for this user
+				if ($itemTarget != $groupItemTarget || (isset($fileSource) && $fileTarget != $groupFileTarget)) {
+					$query->execute(array($itemType, $itemSource, $itemTarget, $parent, self::$shareTypeGroupUserUnique, $uid, $uidOwner, $permissions, time(), $fileSource, $fileTarget));
+					\OC_DB::insertid('*PREFIX*share');
+				}
+			}
+			if ($parentFolder === true) {
+				// Return parent folders to preserve file target paths for potential children
+				return $parentFolders;
+			}
+		} else {
+			$itemTarget = self::generateTarget($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $suggestedItemTarget);
+			if (isset($fileSource)) {
+				if ($parentFolder) {
+					if ($parentFolder === true) {
+						$fileTarget = self::generateTarget('file', $filePath, $shareType, $shareWith, $uidOwner, $suggestedFileTarget);
+						$parentFolders['folder'] = $fileTarget;
+					} else {
+						$fileTarget = $parentFolder['folder'].$itemSource;
+						$parent = $parentFolder['id'];
+					}
+				} else {
+					$fileTarget = self::generateTarget('file', $filePath, $shareType, $shareWith, $uidOwner, $suggestedFileTarget);
+				}
+			} else {
+				$fileTarget = null;
+			}
+			$query->execute(array($itemType, $itemSource, $itemTarget, $parent, $shareType, $shareWith, $uidOwner, $permissions, time(), $fileSource, $fileTarget));
+			$id = \OC_DB::insertid('*PREFIX*share');
+			if ($parentFolder === true) {
+				$parentFolders['id'] = $id;
+				// Return parent folder to preserve file target paths for potential children
+				return $parentFolders;
+			}
+		}
+		return true;
+	}
+
+	/**
+	* @brief Generate a unique target for the item
+	* @param string Item type
+	* @param string Item source
+	* @param int SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
+	* @param string User or group the item is being shared with
+	* @param string The suggested target originating from a reshare (optional)
+	* @param int The id of the parent group share (optional)
+	* @return string Item target
+	*/
+	private static function generateTarget($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $suggestedTarget = null, $groupParent = null) {
+		$backend = self::getBackend($itemType);
+		if ($shareType == self::SHARE_TYPE_LINK) {
+			if (isset($suggestedTarget)) {
+				return $suggestedTarget;
+			}
+			return $backend->generateTarget($itemSource, false);
+		} else {
+			if ($itemType == 'file' || $itemType == 'folder') {
+				$column = 'file_target';
+				$columnSource = 'file_source';
+			} else {
+				$column = 'item_target';
+				$columnSource = 'item_source';
+			}
+			if ($shareType == self::SHARE_TYPE_USER) {
+				// Share with is a user, so set share type to user and groups
+				$shareType = self::$shareTypeUserAndGroups;
+				$userAndGroups = array_merge(array($shareWith), \OC_Group::getUserGroups($shareWith));
+			} else {
+				$userAndGroups = false;
+			}
+			$exclude = null;
+			// Backend has 3 opportunities to generate a unique target
+			for ($i = 0; $i < 2; $i++) {
+				// Check if suggested target exists first
+				if ($i == 0 && isset($suggestedTarget)) {
+					$target = $suggestedTarget;
+				} else {
+					if ($shareType == self::SHARE_TYPE_GROUP) {
+						$target = $backend->generateTarget($itemSource, false, $exclude);
+					} else {
+						$target = $backend->generateTarget($itemSource, $shareWith, $exclude);
+					}
+					if (is_array($exclude) && in_array($target, $exclude)) {
+						break;
+					}
+				}
+				// Check if target already exists
+				$checkTarget = self::getItems($itemType, $target, $shareType, $shareWith);
+				if (!empty($checkTarget)) {
+					foreach ($checkTarget as $item) {
+						// Skip item if it is the group parent row
+						if (isset($groupParent) && $item['id'] == $groupParent) {
+							if (count($checkTarget) == 1) {
+								return $target;
+							} else {
+								continue;
+							}
+						}
+						if ($item['uid_owner'] == $uidOwner) {
+							if ($itemType == 'file' || $itemType == 'folder') {
+								if ($item['file_source'] == \OC_FileCache::getId($itemSource)) {
+									return $target;
+								}
+							} else if ($item['item_source'] == $itemSource) {
+								return $target;
+							}
+						}
+					}
+					if (!isset($exclude)) {
+						$exclude = array();
+					}
+					// Find similar targets to improve backend's chances to generate a unqiue target
+					if ($userAndGroups) {
+						if ($column == 'file_target') {
+							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share` WHERE `item_type` IN (\'file\', \'folder\') AND `share_type` IN (?,?,?) AND `share_with` IN (\''.implode('\',\'', $userAndGroups).'\')');
+							$result = $checkTargets->execute(array(self::SHARE_TYPE_USER, self::SHARE_TYPE_GROUP, self::$shareTypeGroupUserUnique));
+						} else {
+							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share` WHERE `item_type` = ? AND `share_type` IN (?,?,?) AND `share_with` IN (\''.implode('\',\'', $userAndGroups).'\')');
+							$result = $checkTargets->execute(array($itemType, self::SHARE_TYPE_USER, self::SHARE_TYPE_GROUP, self::$shareTypeGroupUserUnique));
+						}
+					} else {
+						if ($column == 'file_target') {
+							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share` WHERE `item_type` IN (\'file\', \'folder\') AND `share_type` = ? AND `share_with` = ?');
+							$result = $checkTargets->execute(array(self::SHARE_TYPE_GROUP, $shareWith));
+						} else {
+							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share` WHERE `item_type` = ? AND `share_type` = ? AND `share_with` = ?');
+							$result = $checkTargets->execute(array($itemType, self::SHARE_TYPE_GROUP, $shareWith));
+						}
+					}
+					while ($row = $result->fetchRow()) {
+						$exclude[] = $row[$column];
+					}
+				} else {
+					return $target;
+				}
+			}
+		}
+		$message = 'Sharing backend registered for '.$itemType.' did not generate a unique target for '.$itemSource;
+		\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
+		throw new \Exception($message);
+	}
+
+	/**
+	* @brief Delete all reshares of an item
+	* @param int Id of item to delete
+	* @param bool If true, exclude the parent from the delete (optional)
+	* @param string The user that the parent was shared with (optinal)
+	*/
+	private static function delete($parent, $excludeParent = false, $uidOwner = null) {
+		$ids = array($parent);
+		$parents = array($parent);
+		while (!empty($parents)) {
+			$parents = "'".implode("','", $parents)."'";
+			// Check the owner on the first search of reshares, useful for finding and deleting the reshares by a single user of a group share
+			if (count($ids) == 1 && isset($uidOwner)) {
+				$query = \OC_DB::prepare('SELECT `id`, `uid_owner`, `item_type`, `item_target`, `parent` FROM `*PREFIX*share` WHERE `parent` IN ('.$parents.') AND `uid_owner` = ?');
+				$result = $query->execute(array($uidOwner));
+			} else {
+				$query = \OC_DB::prepare('SELECT `id`, `item_type`, `item_target`, `parent`, `uid_owner` FROM `*PREFIX*share` WHERE `parent` IN ('.$parents.')');
+				$result = $query->execute();
+			}
+			// Reset parents array, only go through loop again if items are found
+			$parents = array();
+			while ($item = $result->fetchRow()) {
+				// Search for a duplicate parent share, this occurs when an item is shared to the same user through a group and user or the same item is shared by different users
+				$userAndGroups = array_merge(array($item['uid_owner']), \OC_Group::getUserGroups($item['uid_owner']));
+				$query = \OC_DB::prepare('SELECT `id`, `permissions` FROM `*PREFIX*share` WHERE `item_type` = ? AND `item_target` = ? AND `share_type` IN (?,?,?) AND `share_with` IN (\''.implode('\',\'', $userAndGroups).'\') AND `uid_owner` != ? AND `id` != ?');
+				$duplicateParent = $query->execute(array($item['item_type'], $item['item_target'], self::SHARE_TYPE_USER, self::SHARE_TYPE_GROUP, self::$shareTypeGroupUserUnique, $item['uid_owner'], $item['parent']))->fetchRow();
+				if ($duplicateParent) {
+					// Change the parent to the other item id if share permission is granted
+					if ($duplicateParent['permissions'] & self::PERMISSION_SHARE) {
+						$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `parent` = ? WHERE `id` = ?');
+						$query->execute(array($duplicateParent['id'], $item['id']));
+						continue;
+					}
+				}
+				$ids[] = $item['id'];
+				$parents[] = $item['id'];
+			}
+		}
+		if ($excludeParent) {
+			unset($ids[0]);
+		}
+		if (!empty($ids)) {
+			$ids = "'".implode("','", $ids)."'";
+			$query = \OC_DB::prepare('DELETE FROM `*PREFIX*share` WHERE `id` IN ('.$ids.')');
+			$query->execute();
+		}
+	}
+
+	/**
+	* Hook Listeners
+	*/
+
+	public static function post_deleteUser($arguments) {
+		// Delete any items shared with the deleted user
+		$query = \OC_DB::prepare('DELETE FROM `*PREFIX*share` WHERE `share_with` = ? AND `share_type` = ? OR `share_type` = ?');
+		$result = $query->execute(array($arguments['uid'], self::SHARE_TYPE_USER, self::$shareTypeGroupUserUnique));
+		// Delete any items the deleted user shared
+		$query = \OC_DB::prepare('SELECT `id` FROM `*PREFIX*share` WHERE `uid_owner` = ?');
+		$result = $query->execute(array($arguments['uid']));
+		while ($item = $result->fetchRow()) {
+			self::delete($item['id']);
+		}
+	}
+
+	public static function post_addToGroup($arguments) {
+		// Find the group shares and check if the user needs a unique target
+		$query = \OC_DB::prepare('SELECT * FROM `*PREFIX*share` WHERE `share_type` = ? AND `share_with` = ?');
+		$result = $query->execute(array(self::SHARE_TYPE_GROUP, $arguments['gid']));
+		$query = \OC_DB::prepare('INSERT INTO `*PREFIX*share` (`item_type`, `item_source`, `item_target`, `parent`, `share_type`, `share_with`, `uid_owner`, `permissions`, `stime`, `file_source`, `file_target`) VALUES (?,?,?,?,?,?,?,?,?,?,?)');
+		while ($item = $result->fetchRow()) {
+			if ($item['item_type'] == 'file' || $item['item_type'] == 'file') {
+				$itemTarget = null;
+			} else {
+				$itemTarget = self::generateTarget($item['item_type'], $item['item_source'], self::SHARE_TYPE_USER, $arguments['uid'], $item['uid_owner'], $item['item_target'], $item['id']);
+			}
+			if (isset($item['file_source'])) {
+				$fileTarget = self::generateTarget($item['item_type'], $item['item_source'], self::SHARE_TYPE_USER, $arguments['uid'], $item['uid_owner'], $item['file_target'], $item['id']);
+			} else {
+				$fileTarget = null;
+			}
+			// Insert an extra row for the group share if the item or file target is unique for this user
+			if ($itemTarget != $item['item_target'] || $fileTarget != $item['file_target']) {
+				$query->execute(array($item['item_type'], $item['item_source'], $itemTarget, $item['id'], self::$shareTypeGroupUserUnique, $arguments['uid'], $item['uid_owner'], $item['permissions'], $item['stime'], $item['file_source'], $fileTarget));
+				\OC_DB::insertid('*PREFIX*share');
+			}
+		}
+	}
+
+	public static function post_removeFromGroup($arguments) {
+		// TODO Don't call if user deleted?
+		$query = \OC_DB::prepare('SELECT `id`, `share_type` FROM `*PREFIX*share` WHERE (`share_type` = ? AND `share_with` = ?) OR (`share_type` = ? AND `share_with` = ?)');
+		$result = $query->execute(array(self::SHARE_TYPE_GROUP, $arguments['gid'], self::$shareTypeGroupUserUnique, $arguments['uid']));
+		while ($item = $result->fetchRow()) {
+			if ($item['share_type'] == self::SHARE_TYPE_GROUP) {
+				// Delete all reshares by this user of the group share
+				self::delete($item['id'], true, $arguments['uid']);
+			} else {
+				self::delete($item['id']);
+			}
+		}
+	}
+
+	public static function post_deleteGroup($arguments) {
+		$query = \OC_DB::prepare('SELECT id FROM `*PREFIX*share` WHERE `share_type` = ? AND `share_with` = ?');
+		$result = $query->execute(array(self::SHARE_TYPE_GROUP, $arguments['gid']));
+		while ($item = $result->fetchRow()) {
+			self::delete($item['id']);
+		}
+	}
+
+}
+
+/**
+* Interface that apps must implement to share content.
+*/
+interface Share_Backend {
+
+	/**
+	* @brief Get the source of the item to be stored in the database
+	* @param string Item source
+	* @param string Owner of the item
+	* @return mixed|array|false Source
+	*
+	* Return an array if the item is file dependent, the array needs two keys: 'item' and 'file'
+	* Return false if the item does not exist for the user
+	*
+	* The formatItems() function will translate the source returned back into the item
+	*/
+	public function isValidSource($itemSource, $uidOwner);
+
+	/**
+	* @brief Get a unique name of the item for the specified user
+	* @param string Item source
+	* @param string|false User the item is being shared with
+	* @param array|null List of similar item names already existing as shared items
+	* @return string Target name
+	*
+	* This function needs to verify that the user does not already have an item with this name.
+	* If it does generate a new name e.g. name_#
+	*/
+	public function generateTarget($itemSource, $shareWith, $exclude = null);
+
+	/**
+	* @brief Converts the shared item sources back into the item in the specified format
+	* @param array Shared items
+	* @param int Format
+	* @return ?
+	*
+	* The items array is a 3-dimensional array with the item_source as the first key and the share id as the second key to an array with the share info.
+	* The key/value pairs included in the share info depend on the function originally called:
+	* If called by getItem(s)Shared: id, item_type, item, item_source, share_type, share_with, permissions, stime, file_source
+	* If called by getItem(s)SharedWith: id, item_type, item, item_source, item_target, share_type, share_with, permissions, stime, file_source, file_target
+	* This function allows the backend to control the output of shared items with custom formats.
+	* It is only called through calls to the public getItem(s)Shared(With) functions.
+	*/
+	public function formatItems($items, $format, $parameters = null);
+
+}
+
+/**
+* Interface for share backends that share content that is dependent on files.
+* Extends the Share_Backend interface.
+*/
+interface Share_Backend_File_Dependent extends Share_Backend {
+
+	/**
+	* @brief Get the file path of the item
+	* @param
+	* @param
+	* @return
+	*/
+	public function getFilePath($itemSource, $uidOwner);
+
+}
+
+/**
+* Interface for collections of of items implemented by another share backend.
+* Extends the Share_Backend interface.
+*/
+interface Share_Backend_Collection extends Share_Backend {
+
+	/**
+	* @brief Get the sources of the children of the item
+	* @param string Item source
+	* @return array Returns an array of children each inside an array with the keys: source, target, and file_path if applicable
+	*/
+	public function getChildren($itemSource);
+
+}
diff --git a/lib/updater.php b/lib/updater.php
index b3b289ef276d9eded961b47a1eefd921dcf333b5..cb22da4f906de487ec33d959c023b958a39d0554 100644
--- a/lib/updater.php
+++ b/lib/updater.php
@@ -45,12 +45,12 @@ class OC_Updater{
 
 		// set a sensible timeout of 10 sec to stay responsive even if the update server is down.
 		$ctx = stream_context_create(
-			array( 
-				'http' => array( 
-					'timeout' => 10 
-				) 
-			) 
-		); 
+			array(
+				'http' => array(
+					'timeout' => 10
+				)
+			)
+		);
 		$xml=@file_get_contents($url, 0, $ctx);
                 if($xml==FALSE) {
                         return array();
diff --git a/lib/util.php b/lib/util.php
index 9fde98c1972a9d074db48a5674e1ec5424113eee..68c4920258fbdf6e9fa00a1f2f47f36114e139fa 100755
--- a/lib/util.php
+++ b/lib/util.php
@@ -426,7 +426,7 @@ class OC_Util {
 	 * @description
 	 * Also required for the client side to compute the piont in time when to
 	 * request a fresh token. The client will do so when nearly 97% of the
-	 * timespan coded here has expired. 
+	 * timespan coded here has expired.
 	 */
 	public static $callLifespan = 3600; // 3600 secs = 1 hour
 
@@ -564,7 +564,7 @@ class OC_Util {
 	public static function generate_random_bytes($length = 30) {
 
 		// Try to use openssl_random_pseudo_bytes
-		if(function_exists('openssl_random_pseudo_bytes')) { 
+		if(function_exists('openssl_random_pseudo_bytes')) {
 			$pseudo_byte = bin2hex(openssl_random_pseudo_bytes($length, $strong));
 			if($strong == TRUE) {
 				return substr($pseudo_byte, 0, $length); // Truncate it to match the length
@@ -574,31 +574,31 @@ class OC_Util {
 		// Try to use /dev/random
 		$fp = @file_get_contents('/dev/random', false, null, 0, $length);
 		if ($fp !== FALSE) {
-			$string = substr(bin2hex($fp), 0, $length);  
+			$string = substr(bin2hex($fp), 0, $length);
 			return $string;
 		}
 
-		// Fallback to mt_rand() 
+		// Fallback to mt_rand()
 		$characters = '0123456789';
-		$characters .= 'abcdefghijklmnopqrstuvwxyz'; 
+		$characters .= 'abcdefghijklmnopqrstuvwxyz';
 		$charactersLength = strlen($characters)-1;
 		$pseudo_byte = "";
 
 		// Select some random characters
 		for ($i = 0; $i < $length; $i++) {
 			$pseudo_byte .= $characters[mt_rand(0, $charactersLength)];
-		}        
+		}
 		return $pseudo_byte;
 	}
-	
+
 	/*
 	* @brief Checks if a secure random number generator is available
-	* @return bool 
+	* @return bool
 	*/
 	public static function secureRNG_available() {
 
 		// Check openssl_random_pseudo_bytes
-		if(function_exists('openssl_random_pseudo_bytes')) { 
+		if(function_exists('openssl_random_pseudo_bytes')) {
 			openssl_random_pseudo_bytes(1, $strong);
 			if($strong == TRUE) {
 				return true;
@@ -612,5 +612,5 @@ class OC_Util {
 		}
 
 		return false;
-	}	
+	}
 }