Correct checking item source for share from same owner when generating item target

1 files changed, 1242 insertions, 1241 deletions

diff --git a/lib/public/share.php b/lib/public/share.php
index 42c4db61521..e0488b8faf6 100644
--- a/lib/public/share.php
+++ b/lib/public/share.php
@@ -1,1243 +1,1244 @@
-<?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) {
-		$uidOwner = \OC_User::getUser();
-		// Verify share type and sharing conditions are met
-		if ($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 (\OC_Appconfig::getValue('core', 'shareapi_share_policy', 'global') == '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 (!\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`, `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';
-			} else {
-				$column = 'item_target';
-			}
-			if ($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 && $item['item_source'] == \OC_FileCache::getId($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();

+		// 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 (\OC_Appconfig::getValue('core', 'shareapi_share_policy', 'global') == '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 (!\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`, `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 && $item[$columnSource] == $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') {
+						}

+					}

+					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);
-
-}
+							$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);

+

+}