nextcloud / server

lib/private/Share/Share.php

Indentation +2827 added lines, -2827 removed lines

@@ -60,2864 +60,2864 @@
  */
 class Share extends Constants {
 
-	/** 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
-	 * @see lib/public/constants.php
-	 */
-
-	/**
-	 * Register a sharing backend class that implements OCP\Share_Backend for an item type
-	 * @param string $itemType Item type
-	 * @param string $class Backend class
-	 * @param string $collectionOf (optional) Depends on item type
-	 * @param array $supportedFileExtensions (optional) List of supported file extensions if this item type depends on files
-	 * @return boolean true if backend is registered or false if error
-	 */
-	public static function registerBackend($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) {
-					Util::addScript('core', 'merged-share-backend');
-					\OC_Util::addStyle('core', 'share');
-				}
-				return true;
-			}
-			\OCP\Util::writeLog('OCP\Share',
-				'Sharing backend '.$class.' not registered, '.self::$backendTypes[$itemType]['class']
-				.' is already registered for '.$itemType,
-				\OCP\Util::WARN);
-		}
-		return false;
-	}
-
-	/**
-	 * Check if the Share API is enabled
-	 * @return boolean true if enabled or false
-	 *
-	 * The Share API is enabled by default if not configured
-	 */
-	public static function isEnabled() {
-		if (\OC::$server->getAppConfig()->getValue('core', 'shareapi_enabled', 'yes') == 'yes') {
-			return true;
-		}
-		return false;
-	}
-
-	/**
-	 * Find which users can access a shared item
-	 * @param string $path to the file
-	 * @param string $ownerUser owner of the file
-	 * @param IUserManager $userManager
-	 * @param ILogger $logger
-	 * @param boolean $includeOwner include owner to the list of users with access to the file
-	 * @param boolean $returnUserPaths Return an array with the user => path map
-	 * @param boolean $recursive take all parent folders into account (default true)
-	 * @return array
-	 * @note $path needs to be relative to user data dir, e.g. 'file.txt'
-	 *       not '/admin/data/file.txt'
-	 * @throws \OC\User\NoUserException
-	 */
-	public static function getUsersSharingFile($path,
-											   $ownerUser,
-											   IUserManager $userManager,
-											   ILogger $logger,
-											   $includeOwner = false,
-											   $returnUserPaths = false,
-											   $recursive = true) {
-		$userObject = $userManager->get($ownerUser);
-
-		if (is_null($userObject)) {
-			$logger->error(
-				sprintf(
-					'Backends provided no user object for %s',
-					$ownerUser
-				),
-				[
-					'app' => 'files',
-				]
-			);
-			throw new \OC\User\NoUserException('Backends provided no user object');
-		}
-
-		$ownerUser = $userObject->getUID();
-
-		Filesystem::initMountPoints($ownerUser);
-		$shares = $sharePaths = $fileTargets = array();
-		$publicShare = false;
-		$remoteShare = false;
-		$source = -1;
-		$cache = $mountPath = false;
-
-		$view = new \OC\Files\View('/' . $ownerUser . '/files');
-		$meta = $view->getFileInfo($path);
-		if ($meta) {
-			$path = substr($meta->getPath(), strlen('/' . $ownerUser . '/files'));
-		} else {
-			// if the file doesn't exists yet we start with the parent folder
-			$meta = $view->getFileInfo(dirname($path));
-		}
-
-		if($meta !== false) {
-			$source = $meta['fileid'];
-			$cache = new \OC\Files\Cache\Cache($meta['storage']);
-
-			$mountPath = $meta->getMountPoint()->getMountPoint();
-			if ($mountPath !== false) {
-				$mountPath = substr($mountPath, strlen('/' . $ownerUser . '/files'));
-			}
-		}
-
-		$paths = [];
-		while ($source !== -1) {
-			// Fetch all shares with another user
-			if (!$returnUserPaths) {
-				$query = \OC_DB::prepare(
-					'SELECT `share_with`, `file_source`, `file_target`
+    /** CRUDS permissions (Create, Read, Update, Delete, Share) using a bitmask
+     * Construct permissions for share() and setPermissions with Or (|) e.g.
+     * Give user read and update permissions: PERMISSION_READ | PERMISSION_UPDATE
+     *
+     * Check if permission is granted with And (&) e.g. Check if delete is
+     * granted: if ($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
+     * @see lib/public/constants.php
+     */
+
+    /**
+     * Register a sharing backend class that implements OCP\Share_Backend for an item type
+     * @param string $itemType Item type
+     * @param string $class Backend class
+     * @param string $collectionOf (optional) Depends on item type
+     * @param array $supportedFileExtensions (optional) List of supported file extensions if this item type depends on files
+     * @return boolean true if backend is registered or false if error
+     */
+    public static function registerBackend($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) {
+                    Util::addScript('core', 'merged-share-backend');
+                    \OC_Util::addStyle('core', 'share');
+                }
+                return true;
+            }
+            \OCP\Util::writeLog('OCP\Share',
+                'Sharing backend '.$class.' not registered, '.self::$backendTypes[$itemType]['class']
+                .' is already registered for '.$itemType,
+                \OCP\Util::WARN);
+        }
+        return false;
+    }
+
+    /**
+     * Check if the Share API is enabled
+     * @return boolean true if enabled or false
+     *
+     * The Share API is enabled by default if not configured
+     */
+    public static function isEnabled() {
+        if (\OC::$server->getAppConfig()->getValue('core', 'shareapi_enabled', 'yes') == 'yes') {
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Find which users can access a shared item
+     * @param string $path to the file
+     * @param string $ownerUser owner of the file
+     * @param IUserManager $userManager
+     * @param ILogger $logger
+     * @param boolean $includeOwner include owner to the list of users with access to the file
+     * @param boolean $returnUserPaths Return an array with the user => path map
+     * @param boolean $recursive take all parent folders into account (default true)
+     * @return array
+     * @note $path needs to be relative to user data dir, e.g. 'file.txt'
+     *       not '/admin/data/file.txt'
+     * @throws \OC\User\NoUserException
+     */
+    public static function getUsersSharingFile($path,
+                                                $ownerUser,
+                                                IUserManager $userManager,
+                                                ILogger $logger,
+                                                $includeOwner = false,
+                                                $returnUserPaths = false,
+                                                $recursive = true) {
+        $userObject = $userManager->get($ownerUser);
+
+        if (is_null($userObject)) {
+            $logger->error(
+                sprintf(
+                    'Backends provided no user object for %s',
+                    $ownerUser
+                ),
+                [
+                    'app' => 'files',
+                ]
+            );
+            throw new \OC\User\NoUserException('Backends provided no user object');
+        }
+
+        $ownerUser = $userObject->getUID();
+
+        Filesystem::initMountPoints($ownerUser);
+        $shares = $sharePaths = $fileTargets = array();
+        $publicShare = false;
+        $remoteShare = false;
+        $source = -1;
+        $cache = $mountPath = false;
+
+        $view = new \OC\Files\View('/' . $ownerUser . '/files');
+        $meta = $view->getFileInfo($path);
+        if ($meta) {
+            $path = substr($meta->getPath(), strlen('/' . $ownerUser . '/files'));
+        } else {
+            // if the file doesn't exists yet we start with the parent folder
+            $meta = $view->getFileInfo(dirname($path));
+        }
+
+        if($meta !== false) {
+            $source = $meta['fileid'];
+            $cache = new \OC\Files\Cache\Cache($meta['storage']);
+
+            $mountPath = $meta->getMountPoint()->getMountPoint();
+            if ($mountPath !== false) {
+                $mountPath = substr($mountPath, strlen('/' . $ownerUser . '/files'));
+            }
+        }
+
+        $paths = [];
+        while ($source !== -1) {
+            // Fetch all shares with another user
+            if (!$returnUserPaths) {
+                $query = \OC_DB::prepare(
+                    'SELECT `share_with`, `file_source`, `file_target`
 					FROM
 					`*PREFIX*share`
 					WHERE
 					`item_source` = ? AND `share_type` = ? AND `item_type` IN (\'file\', \'folder\')'
-				);
-				$result = $query->execute(array($source, self::SHARE_TYPE_USER));
-			} else {
-				$query = \OC_DB::prepare(
-					'SELECT `share_with`, `file_source`, `file_target`
+                );
+                $result = $query->execute(array($source, self::SHARE_TYPE_USER));
+            } else {
+                $query = \OC_DB::prepare(
+                    'SELECT `share_with`, `file_source`, `file_target`
 				FROM
 				`*PREFIX*share`
 				WHERE
 				`item_source` = ? AND `share_type` IN (?, ?) AND `item_type` IN (\'file\', \'folder\')'
-				);
-				$result = $query->execute(array($source, self::SHARE_TYPE_USER, self::$shareTypeGroupUserUnique));
-			}
-
-			if (\OCP\DB::isError($result)) {
-				\OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage(), \OCP\Util::ERROR);
-			} else {
-				while ($row = $result->fetchRow()) {
-					$shares[] = $row['share_with'];
-					if ($returnUserPaths) {
-						$fileTargets[(int) $row['file_source']][$row['share_with']] = $row;
-					}
-				}
-			}
-
-			// We also need to take group shares into account
-			$query = \OC_DB::prepare(
-				'SELECT `share_with`, `file_source`, `file_target`
+                );
+                $result = $query->execute(array($source, self::SHARE_TYPE_USER, self::$shareTypeGroupUserUnique));
+            }
+
+            if (\OCP\DB::isError($result)) {
+                \OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage(), \OCP\Util::ERROR);
+            } else {
+                while ($row = $result->fetchRow()) {
+                    $shares[] = $row['share_with'];
+                    if ($returnUserPaths) {
+                        $fileTargets[(int) $row['file_source']][$row['share_with']] = $row;
+                    }
+                }
+            }
+
+            // We also need to take group shares into account
+            $query = \OC_DB::prepare(
+                'SELECT `share_with`, `file_source`, `file_target`
 				FROM
 				`*PREFIX*share`
 				WHERE
 				`item_source` = ? AND `share_type` = ? AND `item_type` IN (\'file\', \'folder\')'
-			);
-
-			$result = $query->execute(array($source, self::SHARE_TYPE_GROUP));
-
-			if (\OCP\DB::isError($result)) {
-				\OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage(), \OCP\Util::ERROR);
-			} else {
-				$groupManager = \OC::$server->getGroupManager();
-				while ($row = $result->fetchRow()) {
-
-					$usersInGroup = [];
-					$group = $groupManager->get($row['share_with']);
-					if ($group) {
-						$users = $group->searchUsers('', -1, 0);
-						$userIds = array();
-						foreach ($users as $user) {
-							$userIds[] = $user->getUID();
-						}
-						$usersInGroup = $userIds;
-					}
-					$shares = array_merge($shares, $usersInGroup);
-					if ($returnUserPaths) {
-						foreach ($usersInGroup as $user) {
-							if (!isset($fileTargets[(int) $row['file_source']][$user])) {
-								// When the user already has an entry for this file source
-								// the file is either shared directly with him as well, or
-								// he has an exception entry (because of naming conflict).
-								$fileTargets[(int) $row['file_source']][$user] = $row;
-							}
-						}
-					}
-				}
-			}
-
-			//check for public link shares
-			if (!$publicShare) {
-				$query = \OC_DB::prepare('
+            );
+
+            $result = $query->execute(array($source, self::SHARE_TYPE_GROUP));
+
+            if (\OCP\DB::isError($result)) {
+                \OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage(), \OCP\Util::ERROR);
+            } else {
+                $groupManager = \OC::$server->getGroupManager();
+                while ($row = $result->fetchRow()) {
+
+                    $usersInGroup = [];
+                    $group = $groupManager->get($row['share_with']);
+                    if ($group) {
+                        $users = $group->searchUsers('', -1, 0);
+                        $userIds = array();
+                        foreach ($users as $user) {
+                            $userIds[] = $user->getUID();
+                        }
+                        $usersInGroup = $userIds;
+                    }
+                    $shares = array_merge($shares, $usersInGroup);
+                    if ($returnUserPaths) {
+                        foreach ($usersInGroup as $user) {
+                            if (!isset($fileTargets[(int) $row['file_source']][$user])) {
+                                // When the user already has an entry for this file source
+                                // the file is either shared directly with him as well, or
+                                // he has an exception entry (because of naming conflict).
+                                $fileTargets[(int) $row['file_source']][$user] = $row;
+                            }
+                        }
+                    }
+                }
+            }
+
+            //check for public link shares
+            if (!$publicShare) {
+                $query = \OC_DB::prepare('
 					SELECT `share_with`
 					FROM `*PREFIX*share`
 					WHERE `item_source` = ? AND `share_type` IN (?, ?) AND `item_type` IN (\'file\', \'folder\')', 1
-				);
-
-				$result = $query->execute(array($source, self::SHARE_TYPE_LINK, self::SHARE_TYPE_EMAIL));
-
-				if (\OCP\DB::isError($result)) {
-					\OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage(), \OCP\Util::ERROR);
-				} else {
-					if ($result->fetchRow()) {
-						$publicShare = true;
-					}
-				}
-			}
-
-			//check for remote share
-			if (!$remoteShare) {
-				$query = \OC_DB::prepare('
+                );
+
+                $result = $query->execute(array($source, self::SHARE_TYPE_LINK, self::SHARE_TYPE_EMAIL));
+
+                if (\OCP\DB::isError($result)) {
+                    \OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage(), \OCP\Util::ERROR);
+                } else {
+                    if ($result->fetchRow()) {
+                        $publicShare = true;
+                    }
+                }
+            }
+
+            //check for remote share
+            if (!$remoteShare) {
+                $query = \OC_DB::prepare('
 					SELECT `share_with`
 					FROM `*PREFIX*share`
 					WHERE `item_source` = ? AND `share_type` = ? AND `item_type` IN (\'file\', \'folder\')', 1
-				);
-
-				$result = $query->execute(array($source, self::SHARE_TYPE_REMOTE));
-
-				if (\OCP\DB::isError($result)) {
-					\OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage(), \OCP\Util::ERROR);
-				} else {
-					if ($result->fetchRow()) {
-						$remoteShare = true;
-					}
-				}
-			}
-
-			// let's get the parent for the next round
-			$meta = $cache->get((int)$source);
-			if ($recursive === true && $meta !== false) {
-				$paths[$source] = $meta['path'];
-				$source = (int)$meta['parent'];
-			} else {
-				$source = -1;
-			}
-		}
-
-		// Include owner in list of users, if requested
-		if ($includeOwner) {
-			$shares[] = $ownerUser;
-		}
-
-		if ($returnUserPaths) {
-			$fileTargetIDs = array_keys($fileTargets);
-			$fileTargetIDs = array_unique($fileTargetIDs);
-
-			if (!empty($fileTargetIDs)) {
-				$query = \OC_DB::prepare(
-					'SELECT `fileid`, `path`
+                );
+
+                $result = $query->execute(array($source, self::SHARE_TYPE_REMOTE));
+
+                if (\OCP\DB::isError($result)) {
+                    \OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage(), \OCP\Util::ERROR);
+                } else {
+                    if ($result->fetchRow()) {
+                        $remoteShare = true;
+                    }
+                }
+            }
+
+            // let's get the parent for the next round
+            $meta = $cache->get((int)$source);
+            if ($recursive === true && $meta !== false) {
+                $paths[$source] = $meta['path'];
+                $source = (int)$meta['parent'];
+            } else {
+                $source = -1;
+            }
+        }
+
+        // Include owner in list of users, if requested
+        if ($includeOwner) {
+            $shares[] = $ownerUser;
+        }
+
+        if ($returnUserPaths) {
+            $fileTargetIDs = array_keys($fileTargets);
+            $fileTargetIDs = array_unique($fileTargetIDs);
+
+            if (!empty($fileTargetIDs)) {
+                $query = \OC_DB::prepare(
+                    'SELECT `fileid`, `path`
 					FROM `*PREFIX*filecache`
 					WHERE `fileid` IN (' . implode(',', $fileTargetIDs) . ')'
-				);
-				$result = $query->execute();
-
-				if (\OCP\DB::isError($result)) {
-					\OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage(), \OCP\Util::ERROR);
-				} else {
-					while ($row = $result->fetchRow()) {
-						foreach ($fileTargets[$row['fileid']] as $uid => $shareData) {
-							if ($mountPath !== false) {
-								$sharedPath = $shareData['file_target'];
-								$sharedPath .= substr($path, strlen($mountPath) + strlen($paths[$row['fileid']]));
-								$sharePaths[$uid] = $sharedPath;
-							} else {
-								$sharedPath = $shareData['file_target'];
-								$sharedPath .= substr($path, strlen($row['path']) -5);
-								$sharePaths[$uid] = $sharedPath;
-							}
-						}
-					}
-				}
-			}
-
-			if ($includeOwner) {
-				$sharePaths[$ownerUser] = $path;
-			} else {
-				unset($sharePaths[$ownerUser]);
-			}
-
-			return $sharePaths;
-		}
-
-		return array('users' => array_unique($shares), 'public' => $publicShare, 'remote' => $remoteShare);
-	}
-
-	/**
-	 * Get the items of item type shared with the current user
-	 * @param string $itemType
-	 * @param int $format (optional) Format type must be defined by the backend
-	 * @param mixed $parameters (optional)
-	 * @param int $limit Number of items to return (optional) Returns all by default
-	 * @param boolean $includeCollections (optional)
-	 * @return mixed Return depends on format
-	 */
-	public static function getItemsSharedWith($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);
-	}
-
-	/**
-	 * Get the items of item type shared with a user
-	 * @param string $itemType
-	 * @param string $user id for which user we want the shares
-	 * @param int $format (optional) Format type must be defined by the backend
-	 * @param mixed $parameters (optional)
-	 * @param int $limit Number of items to return (optional) Returns all by default
-	 * @param boolean $includeCollections (optional)
-	 * @return mixed Return depends on format
-	 */
-	public static function getItemsSharedWithUser($itemType, $user, $format = self::FORMAT_NONE,
-												  $parameters = null, $limit = -1, $includeCollections = false) {
-		return self::getItems($itemType, null, self::$shareTypeUserAndGroups, $user, null, $format,
-			$parameters, $limit, $includeCollections);
-	}
-
-	/**
-	 * Get the item of item type shared with the current user
-	 * @param string $itemType
-	 * @param string $itemTarget
-	 * @param int $format (optional) Format type must be defined by the backend
-	 * @param mixed $parameters (optional)
-	 * @param boolean $includeCollections (optional)
-	 * @return mixed Return depends on format
-	 */
-	public static function getItemSharedWith($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);
-	}
-
-	/**
-	 * Get the item of item type shared with a given user by source
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @param string $user User to whom the item was shared
-	 * @param string $owner Owner of the share
-	 * @param int $shareType only look for a specific share type
-	 * @return array Return list of items with file_target, permissions and expiration
-	 */
-	public static function getItemSharedWithUser($itemType, $itemSource, $user, $owner = null, $shareType = null) {
-		$shares = array();
-		$fileDependent = false;
-
-		$where = 'WHERE';
-		$fileDependentWhere = '';
-		if ($itemType === 'file' || $itemType === 'folder') {
-			$fileDependent = true;
-			$column = 'file_source';
-			$fileDependentWhere = 'INNER JOIN `*PREFIX*filecache` ON `file_source` = `*PREFIX*filecache`.`fileid` ';
-			$fileDependentWhere .= 'INNER JOIN `*PREFIX*storages` ON `numeric_id` = `*PREFIX*filecache`.`storage` ';
-		} else {
-			$column = 'item_source';
-		}
-
-		$select = self::createSelectStatement(self::FORMAT_NONE, $fileDependent);
-
-		$where .= ' `' . $column . '` = ? AND `item_type` = ? ';
-		$arguments = array($itemSource, $itemType);
-		// for link shares $user === null
-		if ($user !== null) {
-			$where .= ' AND `share_with` = ? ';
-			$arguments[] = $user;
-		}
-
-		if ($shareType !== null) {
-			$where .= ' AND `share_type` = ? ';
-			$arguments[] = $shareType;
-		}
-
-		if ($owner !== null) {
-			$where .= ' AND `uid_owner` = ? ';
-			$arguments[] = $owner;
-		}
-
-		$query = \OC_DB::prepare('SELECT ' . $select . ' FROM `*PREFIX*share` '. $fileDependentWhere . $where);
-
-		$result = \OC_DB::executeAudited($query, $arguments);
-
-		while ($row = $result->fetchRow()) {
-			if ($fileDependent && !self::isFileReachable($row['path'], $row['storage_id'])) {
-				continue;
-			}
-			if ($fileDependent && (int)$row['file_parent'] === -1) {
-				// if it is a mount point we need to get the path from the mount manager
-				$mountManager = \OC\Files\Filesystem::getMountManager();
-				$mountPoint = $mountManager->findByStorageId($row['storage_id']);
-				if (!empty($mountPoint)) {
-					$path = $mountPoint[0]->getMountPoint();
-					$path = trim($path, '/');
-					$path = substr($path, strlen($owner) + 1); //normalize path to 'files/foo.txt`
-					$row['path'] = $path;
-				} else {
-					\OC::$server->getLogger()->warning(
-						'Could not resolve mount point for ' . $row['storage_id'],
-						['app' => 'OCP\Share']
-					);
-				}
-			}
-			$shares[] = $row;
-		}
-
-		//if didn't found a result than let's look for a group share.
-		if(empty($shares) && $user !== null) {
-			$userObject = \OC::$server->getUserManager()->get($user);
-			$groups = [];
-			if ($userObject) {
-				$groups = \OC::$server->getGroupManager()->getUserGroupIds($userObject);
-			}
-
-			if (!empty($groups)) {
-				$where = $fileDependentWhere . ' WHERE `' . $column . '` = ? AND `item_type` = ? AND `share_with` in (?)';
-				$arguments = array($itemSource, $itemType, $groups);
-				$types = array(null, null, IQueryBuilder::PARAM_STR_ARRAY);
-
-				if ($owner !== null) {
-					$where .= ' AND `uid_owner` = ?';
-					$arguments[] = $owner;
-					$types[] = null;
-				}
-
-				// TODO: inject connection, hopefully one day in the future when this
-				// class isn't static anymore...
-				$conn = \OC::$server->getDatabaseConnection();
-				$result = $conn->executeQuery(
-					'SELECT ' . $select . ' FROM `*PREFIX*share` ' . $where,
-					$arguments,
-					$types
-				);
-
-				while ($row = $result->fetch()) {
-					$shares[] = $row;
-				}
-			}
-		}
-
-		return $shares;
-
-	}
-
-	/**
-	 * Get the item of item type shared with the current user by source
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @param int $format (optional) Format type must be defined by the backend
-	 * @param mixed $parameters
-	 * @param boolean $includeCollections
-	 * @param string $shareWith (optional) define against which user should be checked, default: current user
-	 * @return array
-	 */
-	public static function getItemSharedWithBySource($itemType, $itemSource, $format = self::FORMAT_NONE,
-													 $parameters = null, $includeCollections = false, $shareWith = null) {
-		$shareWith = ($shareWith === null) ? \OC_User::getUser() : $shareWith;
-		return self::getItems($itemType, $itemSource, self::$shareTypeUserAndGroups, $shareWith, null, $format,
-			$parameters, 1, $includeCollections, true);
-	}
-
-	/**
-	 * Get the item of item type shared by a link
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @param string $uidOwner Owner of link
-	 * @return array
-	 */
-	public static function getItemSharedWithByLink($itemType, $itemSource, $uidOwner) {
-		return self::getItems($itemType, $itemSource, self::SHARE_TYPE_LINK, null, $uidOwner, self::FORMAT_NONE,
-			null, 1);
-	}
-
-	/**
-	 * Based on the given token the share information will be returned - password protected shares will be verified
-	 * @param string $token
-	 * @param bool $checkPasswordProtection
-	 * @return array|boolean false will be returned in case the token is unknown or unauthorized
-	 */
-	public static function getShareByToken($token, $checkPasswordProtection = true) {
-		$query = \OC_DB::prepare('SELECT * FROM `*PREFIX*share` WHERE `token` = ?', 1);
-		$result = $query->execute(array($token));
-		if ($result === false) {
-			\OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage() . ', token=' . $token, \OCP\Util::ERROR);
-		}
-		$row = $result->fetchRow();
-		if ($row === false) {
-			return false;
-		}
-		if (is_array($row) and self::expireItem($row)) {
-			return false;
-		}
-
-		// password protected shares need to be authenticated
-		if ($checkPasswordProtection && !\OCP\Share::checkPasswordProtectedShare($row)) {
-			return false;
-		}
-
-		return $row;
-	}
-
-	/**
-	 * resolves reshares down to the last real share
-	 * @param array $linkItem
-	 * @return array file owner
-	 */
-	public static function resolveReShare($linkItem)
-	{
-		if (isset($linkItem['parent'])) {
-			$parent = $linkItem['parent'];
-			while (isset($parent)) {
-				$query = \OC_DB::prepare('SELECT * FROM `*PREFIX*share` WHERE `id` = ?', 1);
-				$item = $query->execute(array($parent))->fetchRow();
-				if (isset($item['parent'])) {
-					$parent = $item['parent'];
-				} else {
-					return $item;
-				}
-			}
-		}
-		return $linkItem;
-	}
-
-
-	/**
-	 * Get the shared items of item type owned by the current user
-	 * @param string $itemType
-	 * @param int $format (optional) Format type must be defined by the backend
-	 * @param mixed $parameters
-	 * @param int $limit Number of items to return (optional) Returns all by default
-	 * @param boolean $includeCollections
-	 * @return mixed Return depends on format
-	 */
-	public static function getItemsShared($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);
-	}
-
-	/**
-	 * Get the shared item of item type owned by the current user
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @param int $format (optional) Format type must be defined by the backend
-	 * @param mixed $parameters
-	 * @param boolean $includeCollections
-	 * @return mixed Return depends on format
-	 */
-	public static function getItemShared($itemType, $itemSource, $format = self::FORMAT_NONE,
-										 $parameters = null, $includeCollections = false) {
-		return self::getItems($itemType, $itemSource, null, null, \OC_User::getUser(), $format,
-			$parameters, -1, $includeCollections);
-	}
-
-	/**
-	 * Get all users an item is shared with
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @param string $uidOwner
-	 * @param boolean $includeCollections
-	 * @param boolean $checkExpireDate
-	 * @return array Return array of users
-	 */
-	public static function getUsersItemShared($itemType, $itemSource, $uidOwner, $includeCollections = false, $checkExpireDate = true) {
-
-		$users = array();
-		$items = self::getItems($itemType, $itemSource, null, null, $uidOwner, self::FORMAT_NONE, null, -1, $includeCollections, false, $checkExpireDate);
-		if ($items) {
-			foreach ($items as $item) {
-				if ((int)$item['share_type'] === self::SHARE_TYPE_USER) {
-					$users[] = $item['share_with'];
-				} else if ((int)$item['share_type'] === self::SHARE_TYPE_GROUP) {
-
-					$group = \OC::$server->getGroupManager()->get($item['share_with']);
-					$userIds = [];
-					if ($group) {
-						$users = $group->searchUsers('', -1, 0);
-						foreach ($users as $user) {
-							$userIds[] = $user->getUID();
-						}
-						return $userIds;
-					}
-
-					$users = array_merge($users, $userIds);
-				}
-			}
-		}
-		return $users;
-	}
-
-	/**
-	 * Share an item with a user, group, or via private link
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
-	 * @param string $shareWith User or group the item is being shared with
-	 * @param int $permissions CRUDS
-	 * @param string $itemSourceName
-	 * @param \DateTime $expirationDate
-	 * @param bool $passwordChanged
-	 * @return boolean|string Returns true on success or false on failure, Returns token on success for links
-	 * @throws \OC\HintException when the share type is remote and the shareWith is invalid
-	 * @throws \Exception
-	 */
-	public static function shareItem($itemType, $itemSource, $shareType, $shareWith, $permissions, $itemSourceName = null, \DateTime $expirationDate = null, $passwordChanged = null) {
-
-		$backend = self::getBackend($itemType);
-		$l = \OC::$server->getL10N('lib');
-
-		if ($backend->isShareTypeAllowed($shareType) === false) {
-			$message = 'Sharing %s failed, because the backend does not allow shares from type %i';
-			$message_t = $l->t('Sharing %s failed, because the backend does not allow shares from type %i', array($itemSourceName, $shareType));
-			\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareType), \OCP\Util::DEBUG);
-			throw new \Exception($message_t);
-		}
-
-		$uidOwner = \OC_User::getUser();
-		$shareWithinGroupOnly = self::shareWithGroupMembersOnly();
-
-		if (is_null($itemSourceName)) {
-			$itemSourceName = $itemSource;
-		}
-		$itemName = $itemSourceName;
-
-		// check if file can be shared
-		if ($itemType === 'file' or $itemType === 'folder') {
-			$path = \OC\Files\Filesystem::getPath($itemSource);
-			$itemName = $path;
-
-			// verify that the file exists before we try to share it
-			if (!$path) {
-				$message = 'Sharing %s failed, because the file does not exist';
-				$message_t = $l->t('Sharing %s failed, because the file does not exist', array($itemSourceName));
-				\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName), \OCP\Util::DEBUG);
-				throw new \Exception($message_t);
-			}
-			// verify that the user has share permission
-			if (!\OC\Files\Filesystem::isSharable($path) || \OCP\Util::isSharingDisabledForUser()) {
-				$message = 'You are not allowed to share %s';
-				$message_t = $l->t('You are not allowed to share %s', [$path]);
-				\OCP\Util::writeLog('OCP\Share', sprintf($message, $path), \OCP\Util::DEBUG);
-				throw new \Exception($message_t);
-			}
-		}
-
-		//verify that we don't share a folder which already contains a share mount point
-		if ($itemType === 'folder') {
-			$path = '/' . $uidOwner . '/files' . \OC\Files\Filesystem::getPath($itemSource) . '/';
-			$mountManager = \OC\Files\Filesystem::getMountManager();
-			$mounts = $mountManager->findIn($path);
-			foreach ($mounts as $mount) {
-				if ($mount->getStorage()->instanceOfStorage('\OCA\Files_Sharing\ISharedStorage')) {
-					$message = 'Sharing "' . $itemSourceName . '" failed, because it contains files shared with you!';
-					\OCP\Util::writeLog('OCP\Share', $message, \OCP\Util::DEBUG);
-					throw new \Exception($message);
-				}
-
-			}
-		}
-
-		// single file shares should never have delete permissions
-		if ($itemType === 'file') {
-			$permissions = (int)$permissions & ~\OCP\Constants::PERMISSION_DELETE;
-		}
-
-		//Validate expirationDate
-		if ($expirationDate !== null) {
-			try {
-				/*
+                );
+                $result = $query->execute();
+
+                if (\OCP\DB::isError($result)) {
+                    \OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage(), \OCP\Util::ERROR);
+                } else {
+                    while ($row = $result->fetchRow()) {
+                        foreach ($fileTargets[$row['fileid']] as $uid => $shareData) {
+                            if ($mountPath !== false) {
+                                $sharedPath = $shareData['file_target'];
+                                $sharedPath .= substr($path, strlen($mountPath) + strlen($paths[$row['fileid']]));
+                                $sharePaths[$uid] = $sharedPath;
+                            } else {
+                                $sharedPath = $shareData['file_target'];
+                                $sharedPath .= substr($path, strlen($row['path']) -5);
+                                $sharePaths[$uid] = $sharedPath;
+                            }
+                        }
+                    }
+                }
+            }
+
+            if ($includeOwner) {
+                $sharePaths[$ownerUser] = $path;
+            } else {
+                unset($sharePaths[$ownerUser]);
+            }
+
+            return $sharePaths;
+        }
+
+        return array('users' => array_unique($shares), 'public' => $publicShare, 'remote' => $remoteShare);
+    }
+
+    /**
+     * Get the items of item type shared with the current user
+     * @param string $itemType
+     * @param int $format (optional) Format type must be defined by the backend
+     * @param mixed $parameters (optional)
+     * @param int $limit Number of items to return (optional) Returns all by default
+     * @param boolean $includeCollections (optional)
+     * @return mixed Return depends on format
+     */
+    public static function getItemsSharedWith($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);
+    }
+
+    /**
+     * Get the items of item type shared with a user
+     * @param string $itemType
+     * @param string $user id for which user we want the shares
+     * @param int $format (optional) Format type must be defined by the backend
+     * @param mixed $parameters (optional)
+     * @param int $limit Number of items to return (optional) Returns all by default
+     * @param boolean $includeCollections (optional)
+     * @return mixed Return depends on format
+     */
+    public static function getItemsSharedWithUser($itemType, $user, $format = self::FORMAT_NONE,
+                                                    $parameters = null, $limit = -1, $includeCollections = false) {
+        return self::getItems($itemType, null, self::$shareTypeUserAndGroups, $user, null, $format,
+            $parameters, $limit, $includeCollections);
+    }
+
+    /**
+     * Get the item of item type shared with the current user
+     * @param string $itemType
+     * @param string $itemTarget
+     * @param int $format (optional) Format type must be defined by the backend
+     * @param mixed $parameters (optional)
+     * @param boolean $includeCollections (optional)
+     * @return mixed Return depends on format
+     */
+    public static function getItemSharedWith($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);
+    }
+
+    /**
+     * Get the item of item type shared with a given user by source
+     * @param string $itemType
+     * @param string $itemSource
+     * @param string $user User to whom the item was shared
+     * @param string $owner Owner of the share
+     * @param int $shareType only look for a specific share type
+     * @return array Return list of items with file_target, permissions and expiration
+     */
+    public static function getItemSharedWithUser($itemType, $itemSource, $user, $owner = null, $shareType = null) {
+        $shares = array();
+        $fileDependent = false;
+
+        $where = 'WHERE';
+        $fileDependentWhere = '';
+        if ($itemType === 'file' || $itemType === 'folder') {
+            $fileDependent = true;
+            $column = 'file_source';
+            $fileDependentWhere = 'INNER JOIN `*PREFIX*filecache` ON `file_source` = `*PREFIX*filecache`.`fileid` ';
+            $fileDependentWhere .= 'INNER JOIN `*PREFIX*storages` ON `numeric_id` = `*PREFIX*filecache`.`storage` ';
+        } else {
+            $column = 'item_source';
+        }
+
+        $select = self::createSelectStatement(self::FORMAT_NONE, $fileDependent);
+
+        $where .= ' `' . $column . '` = ? AND `item_type` = ? ';
+        $arguments = array($itemSource, $itemType);
+        // for link shares $user === null
+        if ($user !== null) {
+            $where .= ' AND `share_with` = ? ';
+            $arguments[] = $user;
+        }
+
+        if ($shareType !== null) {
+            $where .= ' AND `share_type` = ? ';
+            $arguments[] = $shareType;
+        }
+
+        if ($owner !== null) {
+            $where .= ' AND `uid_owner` = ? ';
+            $arguments[] = $owner;
+        }
+
+        $query = \OC_DB::prepare('SELECT ' . $select . ' FROM `*PREFIX*share` '. $fileDependentWhere . $where);
+
+        $result = \OC_DB::executeAudited($query, $arguments);
+
+        while ($row = $result->fetchRow()) {
+            if ($fileDependent && !self::isFileReachable($row['path'], $row['storage_id'])) {
+                continue;
+            }
+            if ($fileDependent && (int)$row['file_parent'] === -1) {
+                // if it is a mount point we need to get the path from the mount manager
+                $mountManager = \OC\Files\Filesystem::getMountManager();
+                $mountPoint = $mountManager->findByStorageId($row['storage_id']);
+                if (!empty($mountPoint)) {
+                    $path = $mountPoint[0]->getMountPoint();
+                    $path = trim($path, '/');
+                    $path = substr($path, strlen($owner) + 1); //normalize path to 'files/foo.txt`
+                    $row['path'] = $path;
+                } else {
+                    \OC::$server->getLogger()->warning(
+                        'Could not resolve mount point for ' . $row['storage_id'],
+                        ['app' => 'OCP\Share']
+                    );
+                }
+            }
+            $shares[] = $row;
+        }
+
+        //if didn't found a result than let's look for a group share.
+        if(empty($shares) && $user !== null) {
+            $userObject = \OC::$server->getUserManager()->get($user);
+            $groups = [];
+            if ($userObject) {
+                $groups = \OC::$server->getGroupManager()->getUserGroupIds($userObject);
+            }
+
+            if (!empty($groups)) {
+                $where = $fileDependentWhere . ' WHERE `' . $column . '` = ? AND `item_type` = ? AND `share_with` in (?)';
+                $arguments = array($itemSource, $itemType, $groups);
+                $types = array(null, null, IQueryBuilder::PARAM_STR_ARRAY);
+
+                if ($owner !== null) {
+                    $where .= ' AND `uid_owner` = ?';
+                    $arguments[] = $owner;
+                    $types[] = null;
+                }
+
+                // TODO: inject connection, hopefully one day in the future when this
+                // class isn't static anymore...
+                $conn = \OC::$server->getDatabaseConnection();
+                $result = $conn->executeQuery(
+                    'SELECT ' . $select . ' FROM `*PREFIX*share` ' . $where,
+                    $arguments,
+                    $types
+                );
+
+                while ($row = $result->fetch()) {
+                    $shares[] = $row;
+                }
+            }
+        }
+
+        return $shares;
+
+    }
+
+    /**
+     * Get the item of item type shared with the current user by source
+     * @param string $itemType
+     * @param string $itemSource
+     * @param int $format (optional) Format type must be defined by the backend
+     * @param mixed $parameters
+     * @param boolean $includeCollections
+     * @param string $shareWith (optional) define against which user should be checked, default: current user
+     * @return array
+     */
+    public static function getItemSharedWithBySource($itemType, $itemSource, $format = self::FORMAT_NONE,
+                                                        $parameters = null, $includeCollections = false, $shareWith = null) {
+        $shareWith = ($shareWith === null) ? \OC_User::getUser() : $shareWith;
+        return self::getItems($itemType, $itemSource, self::$shareTypeUserAndGroups, $shareWith, null, $format,
+            $parameters, 1, $includeCollections, true);
+    }
+
+    /**
+     * Get the item of item type shared by a link
+     * @param string $itemType
+     * @param string $itemSource
+     * @param string $uidOwner Owner of link
+     * @return array
+     */
+    public static function getItemSharedWithByLink($itemType, $itemSource, $uidOwner) {
+        return self::getItems($itemType, $itemSource, self::SHARE_TYPE_LINK, null, $uidOwner, self::FORMAT_NONE,
+            null, 1);
+    }
+
+    /**
+     * Based on the given token the share information will be returned - password protected shares will be verified
+     * @param string $token
+     * @param bool $checkPasswordProtection
+     * @return array|boolean false will be returned in case the token is unknown or unauthorized
+     */
+    public static function getShareByToken($token, $checkPasswordProtection = true) {
+        $query = \OC_DB::prepare('SELECT * FROM `*PREFIX*share` WHERE `token` = ?', 1);
+        $result = $query->execute(array($token));
+        if ($result === false) {
+            \OCP\Util::writeLog('OCP\Share', \OC_DB::getErrorMessage() . ', token=' . $token, \OCP\Util::ERROR);
+        }
+        $row = $result->fetchRow();
+        if ($row === false) {
+            return false;
+        }
+        if (is_array($row) and self::expireItem($row)) {
+            return false;
+        }
+
+        // password protected shares need to be authenticated
+        if ($checkPasswordProtection && !\OCP\Share::checkPasswordProtectedShare($row)) {
+            return false;
+        }
+
+        return $row;
+    }
+
+    /**
+     * resolves reshares down to the last real share
+     * @param array $linkItem
+     * @return array file owner
+     */
+    public static function resolveReShare($linkItem)
+    {
+        if (isset($linkItem['parent'])) {
+            $parent = $linkItem['parent'];
+            while (isset($parent)) {
+                $query = \OC_DB::prepare('SELECT * FROM `*PREFIX*share` WHERE `id` = ?', 1);
+                $item = $query->execute(array($parent))->fetchRow();
+                if (isset($item['parent'])) {
+                    $parent = $item['parent'];
+                } else {
+                    return $item;
+                }
+            }
+        }
+        return $linkItem;
+    }
+
+
+    /**
+     * Get the shared items of item type owned by the current user
+     * @param string $itemType
+     * @param int $format (optional) Format type must be defined by the backend
+     * @param mixed $parameters
+     * @param int $limit Number of items to return (optional) Returns all by default
+     * @param boolean $includeCollections
+     * @return mixed Return depends on format
+     */
+    public static function getItemsShared($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);
+    }
+
+    /**
+     * Get the shared item of item type owned by the current user
+     * @param string $itemType
+     * @param string $itemSource
+     * @param int $format (optional) Format type must be defined by the backend
+     * @param mixed $parameters
+     * @param boolean $includeCollections
+     * @return mixed Return depends on format
+     */
+    public static function getItemShared($itemType, $itemSource, $format = self::FORMAT_NONE,
+                                            $parameters = null, $includeCollections = false) {
+        return self::getItems($itemType, $itemSource, null, null, \OC_User::getUser(), $format,
+            $parameters, -1, $includeCollections);
+    }
+
+    /**
+     * Get all users an item is shared with
+     * @param string $itemType
+     * @param string $itemSource
+     * @param string $uidOwner
+     * @param boolean $includeCollections
+     * @param boolean $checkExpireDate
+     * @return array Return array of users
+     */
+    public static function getUsersItemShared($itemType, $itemSource, $uidOwner, $includeCollections = false, $checkExpireDate = true) {
+
+        $users = array();
+        $items = self::getItems($itemType, $itemSource, null, null, $uidOwner, self::FORMAT_NONE, null, -1, $includeCollections, false, $checkExpireDate);
+        if ($items) {
+            foreach ($items as $item) {
+                if ((int)$item['share_type'] === self::SHARE_TYPE_USER) {
+                    $users[] = $item['share_with'];
+                } else if ((int)$item['share_type'] === self::SHARE_TYPE_GROUP) {
+
+                    $group = \OC::$server->getGroupManager()->get($item['share_with']);
+                    $userIds = [];
+                    if ($group) {
+                        $users = $group->searchUsers('', -1, 0);
+                        foreach ($users as $user) {
+                            $userIds[] = $user->getUID();
+                        }
+                        return $userIds;
+                    }
+
+                    $users = array_merge($users, $userIds);
+                }
+            }
+        }
+        return $users;
+    }
+
+    /**
+     * Share an item with a user, group, or via private link
+     * @param string $itemType
+     * @param string $itemSource
+     * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
+     * @param string $shareWith User or group the item is being shared with
+     * @param int $permissions CRUDS
+     * @param string $itemSourceName
+     * @param \DateTime $expirationDate
+     * @param bool $passwordChanged
+     * @return boolean|string Returns true on success or false on failure, Returns token on success for links
+     * @throws \OC\HintException when the share type is remote and the shareWith is invalid
+     * @throws \Exception
+     */
+    public static function shareItem($itemType, $itemSource, $shareType, $shareWith, $permissions, $itemSourceName = null, \DateTime $expirationDate = null, $passwordChanged = null) {
+
+        $backend = self::getBackend($itemType);
+        $l = \OC::$server->getL10N('lib');
+
+        if ($backend->isShareTypeAllowed($shareType) === false) {
+            $message = 'Sharing %s failed, because the backend does not allow shares from type %i';
+            $message_t = $l->t('Sharing %s failed, because the backend does not allow shares from type %i', array($itemSourceName, $shareType));
+            \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareType), \OCP\Util::DEBUG);
+            throw new \Exception($message_t);
+        }
+
+        $uidOwner = \OC_User::getUser();
+        $shareWithinGroupOnly = self::shareWithGroupMembersOnly();
+
+        if (is_null($itemSourceName)) {
+            $itemSourceName = $itemSource;
+        }
+        $itemName = $itemSourceName;
+
+        // check if file can be shared
+        if ($itemType === 'file' or $itemType === 'folder') {
+            $path = \OC\Files\Filesystem::getPath($itemSource);
+            $itemName = $path;
+
+            // verify that the file exists before we try to share it
+            if (!$path) {
+                $message = 'Sharing %s failed, because the file does not exist';
+                $message_t = $l->t('Sharing %s failed, because the file does not exist', array($itemSourceName));
+                \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName), \OCP\Util::DEBUG);
+                throw new \Exception($message_t);
+            }
+            // verify that the user has share permission
+            if (!\OC\Files\Filesystem::isSharable($path) || \OCP\Util::isSharingDisabledForUser()) {
+                $message = 'You are not allowed to share %s';
+                $message_t = $l->t('You are not allowed to share %s', [$path]);
+                \OCP\Util::writeLog('OCP\Share', sprintf($message, $path), \OCP\Util::DEBUG);
+                throw new \Exception($message_t);
+            }
+        }
+
+        //verify that we don't share a folder which already contains a share mount point
+        if ($itemType === 'folder') {
+            $path = '/' . $uidOwner . '/files' . \OC\Files\Filesystem::getPath($itemSource) . '/';
+            $mountManager = \OC\Files\Filesystem::getMountManager();
+            $mounts = $mountManager->findIn($path);
+            foreach ($mounts as $mount) {
+                if ($mount->getStorage()->instanceOfStorage('\OCA\Files_Sharing\ISharedStorage')) {
+                    $message = 'Sharing "' . $itemSourceName . '" failed, because it contains files shared with you!';
+                    \OCP\Util::writeLog('OCP\Share', $message, \OCP\Util::DEBUG);
+                    throw new \Exception($message);
+                }
+
+            }
+        }
+
+        // single file shares should never have delete permissions
+        if ($itemType === 'file') {
+            $permissions = (int)$permissions & ~\OCP\Constants::PERMISSION_DELETE;
+        }
+
+        //Validate expirationDate
+        if ($expirationDate !== null) {
+            try {
+                /*
 				 * Reuse the validateExpireDate.
 				 * We have to pass time() since the second arg is the time
 				 * the file was shared, since it is not shared yet we just use
 				 * the current time.
 				 */
-				$expirationDate = self::validateExpireDate($expirationDate->format('Y-m-d'), time(), $itemType, $itemSource);
-			} catch (\Exception $e) {
-				throw new \OC\HintException($e->getMessage(), $e->getMessage(), 404);
-			}
-		}
-
-		// Verify share type and sharing conditions are met
-		if ($shareType === self::SHARE_TYPE_USER) {
-			if ($shareWith == $uidOwner) {
-				$message = 'Sharing %s failed, because you can not share with yourself';
-				$message_t = $l->t('Sharing %s failed, because you can not share with yourself', [$itemName]);
-				\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName), \OCP\Util::DEBUG);
-				throw new \Exception($message_t);
-			}
-			if (!\OC_User::userExists($shareWith)) {
-				$message = 'Sharing %s failed, because the user %s does not exist';
-				$message_t = $l->t('Sharing %s failed, because the user %s does not exist', array($itemSourceName, $shareWith));
-				\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
-				throw new \Exception($message_t);
-			}
-			if ($shareWithinGroupOnly) {
-				$userManager = \OC::$server->getUserManager();
-				$groupManager = \OC::$server->getGroupManager();
-				$userOwner = $userManager->get($uidOwner);
-				$userShareWith = $userManager->get($shareWith);
-				$groupsOwner = [];
-				$groupsShareWith = [];
-				if ($userOwner) {
-					$groupsOwner = $groupManager->getUserGroupIds($userOwner);
-				}
-				if ($userShareWith) {
-					$groupsShareWith = $groupManager->getUserGroupIds($userShareWith);
-				}
-				$inGroup = array_intersect($groupsOwner, $groupsShareWith);
-				if (empty($inGroup)) {
-					$message = 'Sharing %s failed, because the user '
-						.'%s is not a member of any groups that %s is a member of';
-					$message_t = $l->t('Sharing %s failed, because the user %s is not a member of any groups that %s is a member of', array($itemName, $shareWith, $uidOwner));
-					\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemName, $shareWith, $uidOwner), \OCP\Util::DEBUG);
-					throw new \Exception($message_t);
-				}
-			}
-			// 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 %s failed, because this item is already shared with %s';
-					$message_t = $l->t('Sharing %s failed, because this item is already shared with %s', array($itemSourceName, $shareWith));
-					\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
-					throw new \Exception($message_t);
-				}
-			}
-			if ($checkExists = self::getItems($itemType, $itemSource, self::SHARE_TYPE_USER,
-				$shareWith, null, self::FORMAT_NONE, null, 1, true, true)) {
-				// Only allow the same share to occur again if it is the same
-				// owner and is not a user share, this use case is for increasing
-				// permissions for a specific user
-				if ($checkExists['uid_owner'] != $uidOwner || $checkExists['share_type'] == $shareType) {
-					$message = 'Sharing %s failed, because this item is already shared with user %s';
-					$message_t = $l->t('Sharing %s failed, because this item is already shared with user %s', array($itemSourceName, $shareWith));
-					\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::ERROR);
-					throw new \Exception($message_t);
-				}
-			}
-		} else if ($shareType === self::SHARE_TYPE_GROUP) {
-			if (!\OC::$server->getGroupManager()->groupExists($shareWith)) {
-				$message = 'Sharing %s failed, because the group %s does not exist';
-				$message_t = $l->t('Sharing %s failed, because the group %s does not exist', array($itemSourceName, $shareWith));
-				\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
-				throw new \Exception($message_t);
-			}
-			if ($shareWithinGroupOnly) {
-				$group = \OC::$server->getGroupManager()->get($shareWith);
-				$user = \OC::$server->getUserManager()->get($uidOwner);
-				if (!$group || !$user || !$group->inGroup($user)) {
-					$message = 'Sharing %s failed, because '
-						. '%s is not a member of the group %s';
-					$message_t = $l->t('Sharing %s failed, because %s is not a member of the group %s', array($itemSourceName, $uidOwner, $shareWith));
-					\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $uidOwner, $shareWith), \OCP\Util::DEBUG);
-					throw new \Exception($message_t);
-				}
-			}
-			// 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, $shareWith,
-				null, self::FORMAT_NONE, null, 1, true, true)) {
-
-				if ($checkExists['share_with'] === $shareWith && $checkExists['share_type'] === \OCP\Share::SHARE_TYPE_GROUP) {
-					$message = 'Sharing %s failed, because this item is already shared with %s';
-					$message_t = $l->t('Sharing %s failed, because this item is already shared with %s', array($itemSourceName, $shareWith));
-					\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
-					throw new \Exception($message_t);
-				}
-			}
-			// Convert share with into an array with the keys group and users
-			$group = $shareWith;
-			$shareWith = array();
-			$shareWith['group'] = $group;
-
-
-			$groupObject = \OC::$server->getGroupManager()->get($group);
-			$userIds = [];
-			if ($groupObject) {
-				$users = $groupObject->searchUsers('', -1, 0);
-				foreach ($users as $user) {
-					$userIds[] = $user->getUID();
-				}
-			}
-
-			$shareWith['users'] = array_diff($userIds, array($uidOwner));
-		} else if ($shareType === self::SHARE_TYPE_LINK) {
-			$updateExistingShare = false;
-			if (\OC::$server->getAppConfig()->getValue('core', 'shareapi_allow_links', 'yes') == 'yes') {
-
-				// IF the password is changed via the old ajax endpoint verify it before deleting the old share
-				if ($passwordChanged === true) {
-					self::verifyPassword($shareWith);
-				}
-
-				// when updating a link share
-				// FIXME Don't delete link if we update it
-				if ($checkExists = self::getItems($itemType, $itemSource, self::SHARE_TYPE_LINK, null,
-					$uidOwner, self::FORMAT_NONE, null, 1)) {
-					// remember old token
-					$oldToken = $checkExists['token'];
-					$oldPermissions = $checkExists['permissions'];
-					//delete the old share
-					Helper::delete($checkExists['id']);
-					$updateExistingShare = true;
-				}
-
-				if ($passwordChanged === null) {
-					// Generate hash of password - same method as user passwords
-					if (is_string($shareWith) && $shareWith !== '') {
-						self::verifyPassword($shareWith);
-						$shareWith = \OC::$server->getHasher()->hash($shareWith);
-					} else {
-						// reuse the already set password, but only if we change permissions
-						// otherwise the user disabled the password protection
-						if ($checkExists && (int)$permissions !== (int)$oldPermissions) {
-							$shareWith = $checkExists['share_with'];
-						}
-					}
-				} else {
-					if ($passwordChanged === true) {
-						if (is_string($shareWith) && $shareWith !== '') {
-							self::verifyPassword($shareWith);
-							$shareWith = \OC::$server->getHasher()->hash($shareWith);
-						}
-					} else if ($updateExistingShare) {
-						$shareWith = $checkExists['share_with'];
-					}
-				}
-
-				if (\OCP\Util::isPublicLinkPasswordRequired() && empty($shareWith)) {
-					$message = 'You need to provide a password to create a public link, only protected links are allowed';
-					$message_t = $l->t('You need to provide a password to create a public link, only protected links are allowed');
-					\OCP\Util::writeLog('OCP\Share', $message, \OCP\Util::DEBUG);
-					throw new \Exception($message_t);
-				}
-
-				if ($updateExistingShare === false &&
-					self::isDefaultExpireDateEnabled() &&
-					empty($expirationDate)) {
-					$expirationDate = Helper::calcExpireDate();
-				}
-
-				// Generate token
-				if (isset($oldToken)) {
-					$token = $oldToken;
-				} else {
-					$token = \OC::$server->getSecureRandom()->generate(self::TOKEN_LENGTH,
-						\OCP\Security\ISecureRandom::CHAR_HUMAN_READABLE
-					);
-				}
-				$result = self::put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions,
-					null, $token, $itemSourceName, $expirationDate);
-				if ($result) {
-					return $token;
-				} else {
-					return false;
-				}
-			}
-			$message = 'Sharing %s failed, because sharing with links is not allowed';
-			$message_t = $l->t('Sharing %s failed, because sharing with links is not allowed', array($itemSourceName));
-			\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName), \OCP\Util::DEBUG);
-			throw new \Exception($message_t);
-		} else if ($shareType === self::SHARE_TYPE_REMOTE) {
-
-			/*
+                $expirationDate = self::validateExpireDate($expirationDate->format('Y-m-d'), time(), $itemType, $itemSource);
+            } catch (\Exception $e) {
+                throw new \OC\HintException($e->getMessage(), $e->getMessage(), 404);
+            }
+        }
+
+        // Verify share type and sharing conditions are met
+        if ($shareType === self::SHARE_TYPE_USER) {
+            if ($shareWith == $uidOwner) {
+                $message = 'Sharing %s failed, because you can not share with yourself';
+                $message_t = $l->t('Sharing %s failed, because you can not share with yourself', [$itemName]);
+                \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName), \OCP\Util::DEBUG);
+                throw new \Exception($message_t);
+            }
+            if (!\OC_User::userExists($shareWith)) {
+                $message = 'Sharing %s failed, because the user %s does not exist';
+                $message_t = $l->t('Sharing %s failed, because the user %s does not exist', array($itemSourceName, $shareWith));
+                \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
+                throw new \Exception($message_t);
+            }
+            if ($shareWithinGroupOnly) {
+                $userManager = \OC::$server->getUserManager();
+                $groupManager = \OC::$server->getGroupManager();
+                $userOwner = $userManager->get($uidOwner);
+                $userShareWith = $userManager->get($shareWith);
+                $groupsOwner = [];
+                $groupsShareWith = [];
+                if ($userOwner) {
+                    $groupsOwner = $groupManager->getUserGroupIds($userOwner);
+                }
+                if ($userShareWith) {
+                    $groupsShareWith = $groupManager->getUserGroupIds($userShareWith);
+                }
+                $inGroup = array_intersect($groupsOwner, $groupsShareWith);
+                if (empty($inGroup)) {
+                    $message = 'Sharing %s failed, because the user '
+                        .'%s is not a member of any groups that %s is a member of';
+                    $message_t = $l->t('Sharing %s failed, because the user %s is not a member of any groups that %s is a member of', array($itemName, $shareWith, $uidOwner));
+                    \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemName, $shareWith, $uidOwner), \OCP\Util::DEBUG);
+                    throw new \Exception($message_t);
+                }
+            }
+            // 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 %s failed, because this item is already shared with %s';
+                    $message_t = $l->t('Sharing %s failed, because this item is already shared with %s', array($itemSourceName, $shareWith));
+                    \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
+                    throw new \Exception($message_t);
+                }
+            }
+            if ($checkExists = self::getItems($itemType, $itemSource, self::SHARE_TYPE_USER,
+                $shareWith, null, self::FORMAT_NONE, null, 1, true, true)) {
+                // Only allow the same share to occur again if it is the same
+                // owner and is not a user share, this use case is for increasing
+                // permissions for a specific user
+                if ($checkExists['uid_owner'] != $uidOwner || $checkExists['share_type'] == $shareType) {
+                    $message = 'Sharing %s failed, because this item is already shared with user %s';
+                    $message_t = $l->t('Sharing %s failed, because this item is already shared with user %s', array($itemSourceName, $shareWith));
+                    \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::ERROR);
+                    throw new \Exception($message_t);
+                }
+            }
+        } else if ($shareType === self::SHARE_TYPE_GROUP) {
+            if (!\OC::$server->getGroupManager()->groupExists($shareWith)) {
+                $message = 'Sharing %s failed, because the group %s does not exist';
+                $message_t = $l->t('Sharing %s failed, because the group %s does not exist', array($itemSourceName, $shareWith));
+                \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
+                throw new \Exception($message_t);
+            }
+            if ($shareWithinGroupOnly) {
+                $group = \OC::$server->getGroupManager()->get($shareWith);
+                $user = \OC::$server->getUserManager()->get($uidOwner);
+                if (!$group || !$user || !$group->inGroup($user)) {
+                    $message = 'Sharing %s failed, because '
+                        . '%s is not a member of the group %s';
+                    $message_t = $l->t('Sharing %s failed, because %s is not a member of the group %s', array($itemSourceName, $uidOwner, $shareWith));
+                    \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $uidOwner, $shareWith), \OCP\Util::DEBUG);
+                    throw new \Exception($message_t);
+                }
+            }
+            // 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, $shareWith,
+                null, self::FORMAT_NONE, null, 1, true, true)) {
+
+                if ($checkExists['share_with'] === $shareWith && $checkExists['share_type'] === \OCP\Share::SHARE_TYPE_GROUP) {
+                    $message = 'Sharing %s failed, because this item is already shared with %s';
+                    $message_t = $l->t('Sharing %s failed, because this item is already shared with %s', array($itemSourceName, $shareWith));
+                    \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
+                    throw new \Exception($message_t);
+                }
+            }
+            // Convert share with into an array with the keys group and users
+            $group = $shareWith;
+            $shareWith = array();
+            $shareWith['group'] = $group;
+
+
+            $groupObject = \OC::$server->getGroupManager()->get($group);
+            $userIds = [];
+            if ($groupObject) {
+                $users = $groupObject->searchUsers('', -1, 0);
+                foreach ($users as $user) {
+                    $userIds[] = $user->getUID();
+                }
+            }
+
+            $shareWith['users'] = array_diff($userIds, array($uidOwner));
+        } else if ($shareType === self::SHARE_TYPE_LINK) {
+            $updateExistingShare = false;
+            if (\OC::$server->getAppConfig()->getValue('core', 'shareapi_allow_links', 'yes') == 'yes') {
+
+                // IF the password is changed via the old ajax endpoint verify it before deleting the old share
+                if ($passwordChanged === true) {
+                    self::verifyPassword($shareWith);
+                }
+
+                // when updating a link share
+                // FIXME Don't delete link if we update it
+                if ($checkExists = self::getItems($itemType, $itemSource, self::SHARE_TYPE_LINK, null,
+                    $uidOwner, self::FORMAT_NONE, null, 1)) {
+                    // remember old token
+                    $oldToken = $checkExists['token'];
+                    $oldPermissions = $checkExists['permissions'];
+                    //delete the old share
+                    Helper::delete($checkExists['id']);
+                    $updateExistingShare = true;
+                }
+
+                if ($passwordChanged === null) {
+                    // Generate hash of password - same method as user passwords
+                    if (is_string($shareWith) && $shareWith !== '') {
+                        self::verifyPassword($shareWith);
+                        $shareWith = \OC::$server->getHasher()->hash($shareWith);
+                    } else {
+                        // reuse the already set password, but only if we change permissions
+                        // otherwise the user disabled the password protection
+                        if ($checkExists && (int)$permissions !== (int)$oldPermissions) {
+                            $shareWith = $checkExists['share_with'];
+                        }
+                    }
+                } else {
+                    if ($passwordChanged === true) {
+                        if (is_string($shareWith) && $shareWith !== '') {
+                            self::verifyPassword($shareWith);
+                            $shareWith = \OC::$server->getHasher()->hash($shareWith);
+                        }
+                    } else if ($updateExistingShare) {
+                        $shareWith = $checkExists['share_with'];
+                    }
+                }
+
+                if (\OCP\Util::isPublicLinkPasswordRequired() && empty($shareWith)) {
+                    $message = 'You need to provide a password to create a public link, only protected links are allowed';
+                    $message_t = $l->t('You need to provide a password to create a public link, only protected links are allowed');
+                    \OCP\Util::writeLog('OCP\Share', $message, \OCP\Util::DEBUG);
+                    throw new \Exception($message_t);
+                }
+
+                if ($updateExistingShare === false &&
+                    self::isDefaultExpireDateEnabled() &&
+                    empty($expirationDate)) {
+                    $expirationDate = Helper::calcExpireDate();
+                }
+
+                // Generate token
+                if (isset($oldToken)) {
+                    $token = $oldToken;
+                } else {
+                    $token = \OC::$server->getSecureRandom()->generate(self::TOKEN_LENGTH,
+                        \OCP\Security\ISecureRandom::CHAR_HUMAN_READABLE
+                    );
+                }
+                $result = self::put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions,
+                    null, $token, $itemSourceName, $expirationDate);
+                if ($result) {
+                    return $token;
+                } else {
+                    return false;
+                }
+            }
+            $message = 'Sharing %s failed, because sharing with links is not allowed';
+            $message_t = $l->t('Sharing %s failed, because sharing with links is not allowed', array($itemSourceName));
+            \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName), \OCP\Util::DEBUG);
+            throw new \Exception($message_t);
+        } else if ($shareType === self::SHARE_TYPE_REMOTE) {
+
+            /*
 			 * Check if file is not already shared with the remote user
 			 */
-			if ($checkExists = self::getItems($itemType, $itemSource, self::SHARE_TYPE_REMOTE,
-				$shareWith, $uidOwner, self::FORMAT_NONE, null, 1, true, true)) {
-					$message = 'Sharing %s failed, because this item is already shared with %s';
-					$message_t = $l->t('Sharing %s failed, because this item is already shared with %s', array($itemSourceName, $shareWith));
-					\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
-					throw new \Exception($message_t);
-			}
-
-			// don't allow federated shares if source and target server are the same
-			list($user, $remote) = Helper::splitUserRemote($shareWith);
-			$currentServer = self::removeProtocolFromUrl(\OC::$server->getURLGenerator()->getAbsoluteURL('/'));
-			$currentUser = \OC::$server->getUserSession()->getUser()->getUID();
-			if (Helper::isSameUserOnSameServer($user, $remote, $currentUser, $currentServer)) {
-				$message = 'Not allowed to create a federated share with the same user.';
-				$message_t = $l->t('Not allowed to create a federated share with the same user');
-				\OCP\Util::writeLog('OCP\Share', $message, \OCP\Util::DEBUG);
-				throw new \Exception($message_t);
-			}
-
-			$token = \OC::$server->getSecureRandom()->generate(self::TOKEN_LENGTH, \OCP\Security\ISecureRandom::CHAR_LOWER . \OCP\Security\ISecureRandom::CHAR_UPPER .
-				\OCP\Security\ISecureRandom::CHAR_DIGITS);
-
-			$shareWith = $user . '@' . $remote;
-			$shareId = self::put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, null, $token, $itemSourceName);
-
-			$send = false;
-			if ($shareId) {
-				$send = self::sendRemoteShare($token, $shareWith, $itemSourceName, $shareId, $uidOwner);
-			}
-
-			if ($send === false) {
-				$currentUser = \OC::$server->getUserSession()->getUser()->getUID();
-				self::unshare($itemType, $itemSource, $shareType, $shareWith, $currentUser);
-				$message_t = $l->t('Sharing %s failed, could not find %s, maybe the server is currently unreachable.', array($itemSourceName, $shareWith));
-				throw new \Exception($message_t);
-			}
-
-			return $send;
-		} else {
-			// Future share types need to include their own conditions
-			$message = 'Share type %s is not valid for %s';
-			$message_t = $l->t('Share type %s is not valid for %s', array($shareType, $itemSource));
-			\OCP\Util::writeLog('OCP\Share', sprintf($message, $shareType, $itemSource), \OCP\Util::DEBUG);
-			throw new \Exception($message_t);
-		}
-
-		// Put the item into the database
-		$result = self::put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, null, null, $itemSourceName, $expirationDate);
-
-		return $result ? true : false;
-	}
-
-	/**
-	 * Unshare an item from a user, group, or delete a private link
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
-	 * @param string $shareWith User or group the item is being shared with
-	 * @param string $owner owner of the share, if null the current user is used
-	 * @return boolean true on success or false on failure
-	 */
-	public static function unshare($itemType, $itemSource, $shareType, $shareWith, $owner = null) {
-
-		// check if it is a valid itemType
-		self::getBackend($itemType);
-
-		$items = self::getItemSharedWithUser($itemType, $itemSource, $shareWith, $owner, $shareType);
-
-		$toDelete = array();
-		$newParent = null;
-		$currentUser = $owner ? $owner : \OC_User::getUser();
-		foreach ($items as $item) {
-			// delete the item with the expected share_type and owner
-			if ((int)$item['share_type'] === (int)$shareType && $item['uid_owner'] === $currentUser) {
-				$toDelete = $item;
-				// if there is more then one result we don't have to delete the children
-				// but update their parent. For group shares the new parent should always be
-				// the original group share and not the db entry with the unique name
-			} else if ((int)$item['share_type'] === self::$shareTypeGroupUserUnique) {
-				$newParent = $item['parent'];
-			} else {
-				$newParent = $item['id'];
-			}
-		}
-
-		if (!empty($toDelete)) {
-			self::unshareItem($toDelete, $newParent);
-			return true;
-		}
-		return false;
-	}
-
-	/**
-	 * Unshare an item from all users, groups, and remove all links
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @return boolean true on success or false on failure
-	 */
-	public static function unshareAll($itemType, $itemSource) {
-		// Get all of the owners of shares of this item.
-		$query = \OC_DB::prepare( 'SELECT `uid_owner` from `*PREFIX*share` WHERE `item_type`=? AND `item_source`=?' );
-		$result = $query->execute(array($itemType, $itemSource));
-		$shares = array();
-		// Add each owner's shares to the array of all shares for this item.
-		while ($row = $result->fetchRow()) {
-			$shares = array_merge($shares, self::getItems($itemType, $itemSource, null, null, $row['uid_owner']));
-		}
-		if (!empty($shares)) {
-			// Pass all the vars we have for now, they may be useful
-			$hookParams = array(
-				'itemType' => $itemType,
-				'itemSource' => $itemSource,
-				'shares' => $shares,
-			);
-			\OC_Hook::emit('OCP\Share', 'pre_unshareAll', $hookParams);
-			foreach ($shares as $share) {
-				self::unshareItem($share);
-			}
-			\OC_Hook::emit('OCP\Share', 'post_unshareAll', $hookParams);
-			return true;
-		}
-		return false;
-	}
-
-	/**
-	 * Unshare an item shared with the current user
-	 * @param string $itemType
-	 * @param string $itemOrigin Item target or source
-	 * @param boolean $originIsSource true if $itemOrigin is the source, false if $itemOrigin is the target (optional)
-	 * @return boolean true on success or false on failure
-	 *
-	 * Unsharing from self is not allowed for items inside collections
-	 */
-	public static function unshareFromSelf($itemType, $itemOrigin, $originIsSource = false) {
-		$originType = ($originIsSource) ? 'source' : 'target';
-		$uid = \OCP\User::getUser();
-
-		if ($itemType === 'file' || $itemType === 'folder') {
-			$statement = 'SELECT * FROM `*PREFIX*share` WHERE `item_type` = ? and `file_' . $originType . '` = ?';
-		} else {
-			$statement = 'SELECT * FROM `*PREFIX*share` WHERE `item_type` = ? and `item_' . $originType . '` = ?';
-		}
-
-		$query = \OCP\DB::prepare($statement);
-		$result = $query->execute(array($itemType, $itemOrigin));
-
-		$shares = $result->fetchAll();
-
-		$listOfUnsharedItems = array();
-
-		$itemUnshared = false;
-		foreach ($shares as $share) {
-			if ((int)$share['share_type'] === \OCP\Share::SHARE_TYPE_USER &&
-				$share['share_with'] === $uid) {
-				$deletedShares = Helper::delete($share['id']);
-				$shareTmp = array(
-					'id' => $share['id'],
-					'shareWith' => $share['share_with'],
-					'itemTarget' => $share['item_target'],
-					'itemType' => $share['item_type'],
-					'shareType' => (int)$share['share_type'],
-				);
-				if (isset($share['file_target'])) {
-					$shareTmp['fileTarget'] = $share['file_target'];
-				}
-				$listOfUnsharedItems = array_merge($listOfUnsharedItems, $deletedShares, array($shareTmp));
-				$itemUnshared = true;
-				break;
-			} elseif ((int)$share['share_type'] === \OCP\Share::SHARE_TYPE_GROUP) {
-				$group = \OC::$server->getGroupManager()->get($share['share_with']);
-				$user = \OC::$server->getUserManager()->get($uid);
-				if ($group && $user && $group->inGroup($user)) {
-					$groupShare = $share;
-				}
-			} elseif ((int)$share['share_type'] === self::$shareTypeGroupUserUnique &&
-				$share['share_with'] === $uid) {
-				$uniqueGroupShare = $share;
-			}
-		}
-
-		if (!$itemUnshared && isset($groupShare) && !isset($uniqueGroupShare)) {
-			$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 (?,?,?,?,?,?,?,?,?,?,?)');
-			$query->execute(array($groupShare['item_type'], $groupShare['item_source'], $groupShare['item_target'],
-				$groupShare['id'], self::$shareTypeGroupUserUnique,
-				\OC_User::getUser(), $groupShare['uid_owner'], 0, $groupShare['stime'], $groupShare['file_source'],
-				$groupShare['file_target']));
-			$shareTmp = array(
-				'id' => $groupShare['id'],
-				'shareWith' => $groupShare['share_with'],
-				'itemTarget' => $groupShare['item_target'],
-				'itemType' => $groupShare['item_type'],
-				'shareType' => (int)$groupShare['share_type'],
-			);
-			if (isset($groupShare['file_target'])) {
-				$shareTmp['fileTarget'] = $groupShare['file_target'];
-			}
-			$listOfUnsharedItems = array_merge($listOfUnsharedItems, [$shareTmp]);
-			$itemUnshared = true;
-		} elseif (!$itemUnshared && isset($uniqueGroupShare)) {
-			$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `permissions` = ? WHERE `id` = ?');
-			$query->execute(array(0, $uniqueGroupShare['id']));
-			$shareTmp = array(
-				'id' => $uniqueGroupShare['id'],
-				'shareWith' => $uniqueGroupShare['share_with'],
-				'itemTarget' => $uniqueGroupShare['item_target'],
-				'itemType' => $uniqueGroupShare['item_type'],
-				'shareType' => (int)$uniqueGroupShare['share_type'],
-			);
-			if (isset($uniqueGroupShare['file_target'])) {
-				$shareTmp['fileTarget'] = $uniqueGroupShare['file_target'];
-			}
-			$listOfUnsharedItems = array_merge($listOfUnsharedItems, [$shareTmp]);
-			$itemUnshared = true;
-		}
-
-		if ($itemUnshared) {
-			\OC_Hook::emit('OCP\Share', 'post_unshareFromSelf',
-				array('unsharedItems' => $listOfUnsharedItems, 'itemType' => $itemType));
-		}
-
-		return $itemUnshared;
-	}
-
-	/**
-	 * sent status if users got informed by mail about share
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
-	 * @param string $recipient with whom was the file shared
-	 * @param boolean $status
-	 */
-	public static function setSendMailStatus($itemType, $itemSource, $shareType, $recipient, $status) {
-		$status = $status ? 1 : 0;
-
-		$query = \OC_DB::prepare(
-			'UPDATE `*PREFIX*share`
+            if ($checkExists = self::getItems($itemType, $itemSource, self::SHARE_TYPE_REMOTE,
+                $shareWith, $uidOwner, self::FORMAT_NONE, null, 1, true, true)) {
+                    $message = 'Sharing %s failed, because this item is already shared with %s';
+                    $message_t = $l->t('Sharing %s failed, because this item is already shared with %s', array($itemSourceName, $shareWith));
+                    \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
+                    throw new \Exception($message_t);
+            }
+
+            // don't allow federated shares if source and target server are the same
+            list($user, $remote) = Helper::splitUserRemote($shareWith);
+            $currentServer = self::removeProtocolFromUrl(\OC::$server->getURLGenerator()->getAbsoluteURL('/'));
+            $currentUser = \OC::$server->getUserSession()->getUser()->getUID();
+            if (Helper::isSameUserOnSameServer($user, $remote, $currentUser, $currentServer)) {
+                $message = 'Not allowed to create a federated share with the same user.';
+                $message_t = $l->t('Not allowed to create a federated share with the same user');
+                \OCP\Util::writeLog('OCP\Share', $message, \OCP\Util::DEBUG);
+                throw new \Exception($message_t);
+            }
+
+            $token = \OC::$server->getSecureRandom()->generate(self::TOKEN_LENGTH, \OCP\Security\ISecureRandom::CHAR_LOWER . \OCP\Security\ISecureRandom::CHAR_UPPER .
+                \OCP\Security\ISecureRandom::CHAR_DIGITS);
+
+            $shareWith = $user . '@' . $remote;
+            $shareId = self::put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, null, $token, $itemSourceName);
+
+            $send = false;
+            if ($shareId) {
+                $send = self::sendRemoteShare($token, $shareWith, $itemSourceName, $shareId, $uidOwner);
+            }
+
+            if ($send === false) {
+                $currentUser = \OC::$server->getUserSession()->getUser()->getUID();
+                self::unshare($itemType, $itemSource, $shareType, $shareWith, $currentUser);
+                $message_t = $l->t('Sharing %s failed, could not find %s, maybe the server is currently unreachable.', array($itemSourceName, $shareWith));
+                throw new \Exception($message_t);
+            }
+
+            return $send;
+        } else {
+            // Future share types need to include their own conditions
+            $message = 'Share type %s is not valid for %s';
+            $message_t = $l->t('Share type %s is not valid for %s', array($shareType, $itemSource));
+            \OCP\Util::writeLog('OCP\Share', sprintf($message, $shareType, $itemSource), \OCP\Util::DEBUG);
+            throw new \Exception($message_t);
+        }
+
+        // Put the item into the database
+        $result = self::put($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, null, null, $itemSourceName, $expirationDate);
+
+        return $result ? true : false;
+    }
+
+    /**
+     * Unshare an item from a user, group, or delete a private link
+     * @param string $itemType
+     * @param string $itemSource
+     * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
+     * @param string $shareWith User or group the item is being shared with
+     * @param string $owner owner of the share, if null the current user is used
+     * @return boolean true on success or false on failure
+     */
+    public static function unshare($itemType, $itemSource, $shareType, $shareWith, $owner = null) {
+
+        // check if it is a valid itemType
+        self::getBackend($itemType);
+
+        $items = self::getItemSharedWithUser($itemType, $itemSource, $shareWith, $owner, $shareType);
+
+        $toDelete = array();
+        $newParent = null;
+        $currentUser = $owner ? $owner : \OC_User::getUser();
+        foreach ($items as $item) {
+            // delete the item with the expected share_type and owner
+            if ((int)$item['share_type'] === (int)$shareType && $item['uid_owner'] === $currentUser) {
+                $toDelete = $item;
+                // if there is more then one result we don't have to delete the children
+                // but update their parent. For group shares the new parent should always be
+                // the original group share and not the db entry with the unique name
+            } else if ((int)$item['share_type'] === self::$shareTypeGroupUserUnique) {
+                $newParent = $item['parent'];
+            } else {
+                $newParent = $item['id'];
+            }
+        }
+
+        if (!empty($toDelete)) {
+            self::unshareItem($toDelete, $newParent);
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Unshare an item from all users, groups, and remove all links
+     * @param string $itemType
+     * @param string $itemSource
+     * @return boolean true on success or false on failure
+     */
+    public static function unshareAll($itemType, $itemSource) {
+        // Get all of the owners of shares of this item.
+        $query = \OC_DB::prepare( 'SELECT `uid_owner` from `*PREFIX*share` WHERE `item_type`=? AND `item_source`=?' );
+        $result = $query->execute(array($itemType, $itemSource));
+        $shares = array();
+        // Add each owner's shares to the array of all shares for this item.
+        while ($row = $result->fetchRow()) {
+            $shares = array_merge($shares, self::getItems($itemType, $itemSource, null, null, $row['uid_owner']));
+        }
+        if (!empty($shares)) {
+            // Pass all the vars we have for now, they may be useful
+            $hookParams = array(
+                'itemType' => $itemType,
+                'itemSource' => $itemSource,
+                'shares' => $shares,
+            );
+            \OC_Hook::emit('OCP\Share', 'pre_unshareAll', $hookParams);
+            foreach ($shares as $share) {
+                self::unshareItem($share);
+            }
+            \OC_Hook::emit('OCP\Share', 'post_unshareAll', $hookParams);
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Unshare an item shared with the current user
+     * @param string $itemType
+     * @param string $itemOrigin Item target or source
+     * @param boolean $originIsSource true if $itemOrigin is the source, false if $itemOrigin is the target (optional)
+     * @return boolean true on success or false on failure
+     *
+     * Unsharing from self is not allowed for items inside collections
+     */
+    public static function unshareFromSelf($itemType, $itemOrigin, $originIsSource = false) {
+        $originType = ($originIsSource) ? 'source' : 'target';
+        $uid = \OCP\User::getUser();
+
+        if ($itemType === 'file' || $itemType === 'folder') {
+            $statement = 'SELECT * FROM `*PREFIX*share` WHERE `item_type` = ? and `file_' . $originType . '` = ?';
+        } else {
+            $statement = 'SELECT * FROM `*PREFIX*share` WHERE `item_type` = ? and `item_' . $originType . '` = ?';
+        }
+
+        $query = \OCP\DB::prepare($statement);
+        $result = $query->execute(array($itemType, $itemOrigin));
+
+        $shares = $result->fetchAll();
+
+        $listOfUnsharedItems = array();
+
+        $itemUnshared = false;
+        foreach ($shares as $share) {
+            if ((int)$share['share_type'] === \OCP\Share::SHARE_TYPE_USER &&
+                $share['share_with'] === $uid) {
+                $deletedShares = Helper::delete($share['id']);
+                $shareTmp = array(
+                    'id' => $share['id'],
+                    'shareWith' => $share['share_with'],
+                    'itemTarget' => $share['item_target'],
+                    'itemType' => $share['item_type'],
+                    'shareType' => (int)$share['share_type'],
+                );
+                if (isset($share['file_target'])) {
+                    $shareTmp['fileTarget'] = $share['file_target'];
+                }
+                $listOfUnsharedItems = array_merge($listOfUnsharedItems, $deletedShares, array($shareTmp));
+                $itemUnshared = true;
+                break;
+            } elseif ((int)$share['share_type'] === \OCP\Share::SHARE_TYPE_GROUP) {
+                $group = \OC::$server->getGroupManager()->get($share['share_with']);
+                $user = \OC::$server->getUserManager()->get($uid);
+                if ($group && $user && $group->inGroup($user)) {
+                    $groupShare = $share;
+                }
+            } elseif ((int)$share['share_type'] === self::$shareTypeGroupUserUnique &&
+                $share['share_with'] === $uid) {
+                $uniqueGroupShare = $share;
+            }
+        }
+
+        if (!$itemUnshared && isset($groupShare) && !isset($uniqueGroupShare)) {
+            $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 (?,?,?,?,?,?,?,?,?,?,?)');
+            $query->execute(array($groupShare['item_type'], $groupShare['item_source'], $groupShare['item_target'],
+                $groupShare['id'], self::$shareTypeGroupUserUnique,
+                \OC_User::getUser(), $groupShare['uid_owner'], 0, $groupShare['stime'], $groupShare['file_source'],
+                $groupShare['file_target']));
+            $shareTmp = array(
+                'id' => $groupShare['id'],
+                'shareWith' => $groupShare['share_with'],
+                'itemTarget' => $groupShare['item_target'],
+                'itemType' => $groupShare['item_type'],
+                'shareType' => (int)$groupShare['share_type'],
+            );
+            if (isset($groupShare['file_target'])) {
+                $shareTmp['fileTarget'] = $groupShare['file_target'];
+            }
+            $listOfUnsharedItems = array_merge($listOfUnsharedItems, [$shareTmp]);
+            $itemUnshared = true;
+        } elseif (!$itemUnshared && isset($uniqueGroupShare)) {
+            $query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `permissions` = ? WHERE `id` = ?');
+            $query->execute(array(0, $uniqueGroupShare['id']));
+            $shareTmp = array(
+                'id' => $uniqueGroupShare['id'],
+                'shareWith' => $uniqueGroupShare['share_with'],
+                'itemTarget' => $uniqueGroupShare['item_target'],
+                'itemType' => $uniqueGroupShare['item_type'],
+                'shareType' => (int)$uniqueGroupShare['share_type'],
+            );
+            if (isset($uniqueGroupShare['file_target'])) {
+                $shareTmp['fileTarget'] = $uniqueGroupShare['file_target'];
+            }
+            $listOfUnsharedItems = array_merge($listOfUnsharedItems, [$shareTmp]);
+            $itemUnshared = true;
+        }
+
+        if ($itemUnshared) {
+            \OC_Hook::emit('OCP\Share', 'post_unshareFromSelf',
+                array('unsharedItems' => $listOfUnsharedItems, 'itemType' => $itemType));
+        }
+
+        return $itemUnshared;
+    }
+
+    /**
+     * sent status if users got informed by mail about share
+     * @param string $itemType
+     * @param string $itemSource
+     * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
+     * @param string $recipient with whom was the file shared
+     * @param boolean $status
+     */
+    public static function setSendMailStatus($itemType, $itemSource, $shareType, $recipient, $status) {
+        $status = $status ? 1 : 0;
+
+        $query = \OC_DB::prepare(
+            'UPDATE `*PREFIX*share`
 					SET `mail_send` = ?
 					WHERE `item_type` = ? AND `item_source` = ? AND `share_type` = ? AND `share_with` = ?');
 
-		$result = $query->execute(array($status, $itemType, $itemSource, $shareType, $recipient));
-
-		if($result === false) {
-			\OCP\Util::writeLog('OCP\Share', 'Couldn\'t set send mail status', \OCP\Util::ERROR);
-		}
-	}
-
-	/**
-	 * Set the permissions of an item for a specific user or group
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
-	 * @param string $shareWith User or group the item is being shared with
-	 * @param int $permissions CRUDS permissions
-	 * @return boolean true on success or false on failure
-	 * @throws \Exception when trying to grant more permissions then the user has himself
-	 */
-	public static function setPermissions($itemType, $itemSource, $shareType, $shareWith, $permissions) {
-		$l = \OC::$server->getL10N('lib');
-		$connection = \OC::$server->getDatabaseConnection();
-
-		$intArrayToLiteralArray = function($intArray, $eb) {
-			return array_map(function($int) use ($eb) {
-				return $eb->literal((int)$int, 'integer');
-			}, $intArray);
-		};
-		$sanitizeItem = function($item) {
-			$item['id'] = (int)$item['id'];
-			$item['premissions'] = (int)$item['permissions'];
-			return $item;
-		};
-
-		if ($rootItem = self::getItems($itemType, $itemSource, $shareType, $shareWith,
-			\OC_User::getUser(), self::FORMAT_NONE, null, 1, false)) {
-			// Check if this item is a reshare and verify that the permissions
-			// granted don't exceed the parent shared item
-			if (isset($rootItem['parent'])) {
-				$qb = $connection->getQueryBuilder();
-				$qb->select('permissions')
-					->from('share')
-					->where($qb->expr()->eq('id', $qb->createParameter('id')))
-					->setParameter(':id', $rootItem['parent']);
-				$dbresult = $qb->execute();
-
-				$result = $dbresult->fetch();
-				$dbresult->closeCursor();
-				if (~(int)$result['permissions'] & $permissions) {
-					$message = 'Setting permissions for %s failed,'
-						.' because the permissions exceed permissions granted to %s';
-					$message_t = $l->t('Setting permissions for %s failed, because the permissions exceed permissions granted to %s', array($itemSource, \OC_User::getUser()));
-					\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSource, \OC_User::getUser()), \OCP\Util::DEBUG);
-					throw new \Exception($message_t);
-				}
-			}
-			$qb = $connection->getQueryBuilder();
-			$qb->update('share')
-				->set('permissions', $qb->createParameter('permissions'))
-				->where($qb->expr()->eq('id', $qb->createParameter('id')))
-				->setParameter(':id', $rootItem['id'])
-				->setParameter(':permissions', $permissions);
-			$qb->execute();
-			if ($itemType === 'file' || $itemType === 'folder') {
-				\OC_Hook::emit('OCP\Share', 'post_update_permissions', array(
-					'itemType' => $itemType,
-					'itemSource' => $itemSource,
-					'shareType' => $shareType,
-					'shareWith' => $shareWith,
-					'uidOwner' => \OC_User::getUser(),
-					'permissions' => $permissions,
-					'path' => $rootItem['path'],
-					'share' => $rootItem
-				));
-			}
-
-			// Share id's to update with the new permissions
-			$ids = [];
-			$items = [];
-
-			// Check if permissions were removed
-			if ((int)$rootItem['permissions'] & ~$permissions) {
-				// If share permission is removed all reshares must be deleted
-				if (($rootItem['permissions'] & \OCP\Constants::PERMISSION_SHARE) && (~$permissions & \OCP\Constants::PERMISSION_SHARE)) {
-					// delete all shares, keep parent and group children
-					Helper::delete($rootItem['id'], true, null, null, true);
-				}
-
-				// Remove permission from all children
-				$parents = [$rootItem['id']];
-				while (!empty($parents)) {
-					$parents = $intArrayToLiteralArray($parents, $qb->expr());
-					$qb = $connection->getQueryBuilder();
-					$qb->select('id', 'permissions', 'item_type')
-						->from('share')
-						->where($qb->expr()->in('parent', $parents));
-					$result = $qb->execute();
-					// Reset parents array, only go through loop again if
-					// items are found that need permissions removed
-					$parents = [];
-					while ($item = $result->fetch()) {
-						$item = $sanitizeItem($item);
-
-						$items[] = $item;
-						// Check if permissions need to be removed
-						if ($item['permissions'] & ~$permissions) {
-							// Add to list of items that need permissions removed
-							$ids[] = $item['id'];
-							$parents[] = $item['id'];
-						}
-					}
-					$result->closeCursor();
-				}
-
-				// Remove the permissions for all reshares of this item
-				if (!empty($ids)) {
-					$ids = "'".implode("','", $ids)."'";
-					// TODO this should be done with Doctrine platform objects
-					if (\OC::$server->getConfig()->getSystemValue("dbtype") === 'oci') {
-						$andOp = 'BITAND(`permissions`, ?)';
-					} else {
-						$andOp = '`permissions` & ?';
-					}
-					$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `permissions` = '.$andOp
-						.' WHERE `id` IN ('.$ids.')');
-					$query->execute(array($permissions));
-				}
-
-			}
-
-			/*
+        $result = $query->execute(array($status, $itemType, $itemSource, $shareType, $recipient));
+
+        if($result === false) {
+            \OCP\Util::writeLog('OCP\Share', 'Couldn\'t set send mail status', \OCP\Util::ERROR);
+        }
+    }
+
+    /**
+     * Set the permissions of an item for a specific user or group
+     * @param string $itemType
+     * @param string $itemSource
+     * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
+     * @param string $shareWith User or group the item is being shared with
+     * @param int $permissions CRUDS permissions
+     * @return boolean true on success or false on failure
+     * @throws \Exception when trying to grant more permissions then the user has himself
+     */
+    public static function setPermissions($itemType, $itemSource, $shareType, $shareWith, $permissions) {
+        $l = \OC::$server->getL10N('lib');
+        $connection = \OC::$server->getDatabaseConnection();
+
+        $intArrayToLiteralArray = function($intArray, $eb) {
+            return array_map(function($int) use ($eb) {
+                return $eb->literal((int)$int, 'integer');
+            }, $intArray);
+        };
+        $sanitizeItem = function($item) {
+            $item['id'] = (int)$item['id'];
+            $item['premissions'] = (int)$item['permissions'];
+            return $item;
+        };
+
+        if ($rootItem = self::getItems($itemType, $itemSource, $shareType, $shareWith,
+            \OC_User::getUser(), self::FORMAT_NONE, null, 1, false)) {
+            // Check if this item is a reshare and verify that the permissions
+            // granted don't exceed the parent shared item
+            if (isset($rootItem['parent'])) {
+                $qb = $connection->getQueryBuilder();
+                $qb->select('permissions')
+                    ->from('share')
+                    ->where($qb->expr()->eq('id', $qb->createParameter('id')))
+                    ->setParameter(':id', $rootItem['parent']);
+                $dbresult = $qb->execute();
+
+                $result = $dbresult->fetch();
+                $dbresult->closeCursor();
+                if (~(int)$result['permissions'] & $permissions) {
+                    $message = 'Setting permissions for %s failed,'
+                        .' because the permissions exceed permissions granted to %s';
+                    $message_t = $l->t('Setting permissions for %s failed, because the permissions exceed permissions granted to %s', array($itemSource, \OC_User::getUser()));
+                    \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSource, \OC_User::getUser()), \OCP\Util::DEBUG);
+                    throw new \Exception($message_t);
+                }
+            }
+            $qb = $connection->getQueryBuilder();
+            $qb->update('share')
+                ->set('permissions', $qb->createParameter('permissions'))
+                ->where($qb->expr()->eq('id', $qb->createParameter('id')))
+                ->setParameter(':id', $rootItem['id'])
+                ->setParameter(':permissions', $permissions);
+            $qb->execute();
+            if ($itemType === 'file' || $itemType === 'folder') {
+                \OC_Hook::emit('OCP\Share', 'post_update_permissions', array(
+                    'itemType' => $itemType,
+                    'itemSource' => $itemSource,
+                    'shareType' => $shareType,
+                    'shareWith' => $shareWith,
+                    'uidOwner' => \OC_User::getUser(),
+                    'permissions' => $permissions,
+                    'path' => $rootItem['path'],
+                    'share' => $rootItem
+                ));
+            }
+
+            // Share id's to update with the new permissions
+            $ids = [];
+            $items = [];
+
+            // Check if permissions were removed
+            if ((int)$rootItem['permissions'] & ~$permissions) {
+                // If share permission is removed all reshares must be deleted
+                if (($rootItem['permissions'] & \OCP\Constants::PERMISSION_SHARE) && (~$permissions & \OCP\Constants::PERMISSION_SHARE)) {
+                    // delete all shares, keep parent and group children
+                    Helper::delete($rootItem['id'], true, null, null, true);
+                }
+
+                // Remove permission from all children
+                $parents = [$rootItem['id']];
+                while (!empty($parents)) {
+                    $parents = $intArrayToLiteralArray($parents, $qb->expr());
+                    $qb = $connection->getQueryBuilder();
+                    $qb->select('id', 'permissions', 'item_type')
+                        ->from('share')
+                        ->where($qb->expr()->in('parent', $parents));
+                    $result = $qb->execute();
+                    // Reset parents array, only go through loop again if
+                    // items are found that need permissions removed
+                    $parents = [];
+                    while ($item = $result->fetch()) {
+                        $item = $sanitizeItem($item);
+
+                        $items[] = $item;
+                        // Check if permissions need to be removed
+                        if ($item['permissions'] & ~$permissions) {
+                            // Add to list of items that need permissions removed
+                            $ids[] = $item['id'];
+                            $parents[] = $item['id'];
+                        }
+                    }
+                    $result->closeCursor();
+                }
+
+                // Remove the permissions for all reshares of this item
+                if (!empty($ids)) {
+                    $ids = "'".implode("','", $ids)."'";
+                    // TODO this should be done with Doctrine platform objects
+                    if (\OC::$server->getConfig()->getSystemValue("dbtype") === 'oci') {
+                        $andOp = 'BITAND(`permissions`, ?)';
+                    } else {
+                        $andOp = '`permissions` & ?';
+                    }
+                    $query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `permissions` = '.$andOp
+                        .' WHERE `id` IN ('.$ids.')');
+                    $query->execute(array($permissions));
+                }
+
+            }
+
+            /*
 			 * Permissions were added
 			 * Update all USERGROUP shares. (So group shares where the user moved their mountpoint).
 			 */
-			if ($permissions & ~(int)$rootItem['permissions']) {
-				$qb = $connection->getQueryBuilder();
-				$qb->select('id', 'permissions', 'item_type')
-					->from('share')
-					->where($qb->expr()->eq('parent', $qb->createParameter('parent')))
-					->andWhere($qb->expr()->eq('share_type', $qb->createParameter('share_type')))
-					->andWhere($qb->expr()->neq('permissions', $qb->createParameter('shareDeleted')))
-					->setParameter(':parent', (int)$rootItem['id'])
-					->setParameter(':share_type', 2)
-					->setParameter(':shareDeleted', 0);
-				$result = $qb->execute();
-
-				$ids = [];
-				while ($item = $result->fetch()) {
-					$item = $sanitizeItem($item);
-					$items[] = $item;
-					$ids[] = $item['id'];
-				}
-				$result->closeCursor();
-
-				// Add permssions for all USERGROUP shares of this item
-				if (!empty($ids)) {
-					$ids = $intArrayToLiteralArray($ids, $qb->expr());
-
-					$qb = $connection->getQueryBuilder();
-					$qb->update('share')
-						->set('permissions', $qb->createParameter('permissions'))
-						->where($qb->expr()->in('id', $ids))
-						->setParameter(':permissions', $permissions);
-					$qb->execute();
-				}
-			}
-
-			foreach ($items as $item) {
-				\OC_Hook::emit('OCP\Share', 'post_update_permissions', ['share' => $item]);
-			}
-
-			return true;
-		}
-		$message = 'Setting permissions for %s failed, because the item was not found';
-		$message_t = $l->t('Setting permissions for %s failed, because the item was not found', array($itemSource));
-
-		\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSource), \OCP\Util::DEBUG);
-		throw new \Exception($message_t);
-	}
-
-	/**
-	 * validate expiration date if it meets all constraints
-	 *
-	 * @param string $expireDate well formatted date string, e.g. "DD-MM-YYYY"
-	 * @param string $shareTime timestamp when the file was shared
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @return \DateTime validated date
-	 * @throws \Exception when the expire date is in the past or further in the future then the enforced date
-	 */
-	private static function validateExpireDate($expireDate, $shareTime, $itemType, $itemSource) {
-		$l = \OC::$server->getL10N('lib');
-		$date = new \DateTime($expireDate);
-		$today = new \DateTime('now');
-
-		// if the user doesn't provide a share time we need to get it from the database
-		// fall-back mode to keep API stable, because the $shareTime parameter was added later
-		$defaultExpireDateEnforced = \OCP\Util::isDefaultExpireDateEnforced();
-		if ($defaultExpireDateEnforced && $shareTime === null) {
-			$items = self::getItemShared($itemType, $itemSource);
-			$firstItem = reset($items);
-			$shareTime = (int)$firstItem['stime'];
-		}
-
-		if ($defaultExpireDateEnforced) {
-			// initialize max date with share time
-			$maxDate = new \DateTime();
-			$maxDate->setTimestamp($shareTime);
-			$maxDays = \OCP\Config::getAppValue('core', 'shareapi_expire_after_n_days', '7');
-			$maxDate->add(new \DateInterval('P' . $maxDays . 'D'));
-			if ($date > $maxDate) {
-				$warning = 'Cannot set expiration date. Shares cannot expire later than ' . $maxDays . ' after they have been shared';
-				$warning_t = $l->t('Cannot set expiration date. Shares cannot expire later than %s after they have been shared', array($maxDays));
-				\OCP\Util::writeLog('OCP\Share', $warning, \OCP\Util::WARN);
-				throw new \Exception($warning_t);
-			}
-		}
-
-		if ($date < $today) {
-			$message = 'Cannot set expiration date. Expiration date is in the past';
-			$message_t = $l->t('Cannot set expiration date. Expiration date is in the past');
-			\OCP\Util::writeLog('OCP\Share', $message, \OCP\Util::WARN);
-			throw new \Exception($message_t);
-		}
-
-		return $date;
-	}
-
-	/**
-	 * Set expiration date for a share
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @param string $date expiration date
-	 * @param int $shareTime timestamp from when the file was shared
-	 * @return boolean
-	 * @throws \Exception when the expire date is not set, in the past or further in the future then the enforced date
-	 */
-	public static function setExpirationDate($itemType, $itemSource, $date, $shareTime = null) {
-		$user = \OC_User::getUser();
-		$l = \OC::$server->getL10N('lib');
-
-		if ($date == '') {
-			if (\OCP\Util::isDefaultExpireDateEnforced()) {
-				$warning = 'Cannot clear expiration date. Shares are required to have an expiration date.';
-				$warning_t = $l->t('Cannot clear expiration date. Shares are required to have an expiration date.');
-				\OCP\Util::writeLog('OCP\Share', $warning, \OCP\Util::WARN);
-				throw new \Exception($warning_t);
-			} else {
-				$date = null;
-			}
-		} else {
-			$date = self::validateExpireDate($date, $shareTime, $itemType, $itemSource);
-		}
-		$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `expiration` = ? WHERE `item_type` = ? AND `item_source` = ?  AND `uid_owner` = ? AND `share_type` = ?');
-		$query->bindValue(1, $date, 'datetime');
-		$query->bindValue(2, $itemType);
-		$query->bindValue(3, $itemSource);
-		$query->bindValue(4, $user);
-		$query->bindValue(5, \OCP\Share::SHARE_TYPE_LINK);
-
-		$query->execute();
-
-		\OC_Hook::emit('OCP\Share', 'post_set_expiration_date', array(
-			'itemType' => $itemType,
-			'itemSource' => $itemSource,
-			'date' => $date,
-			'uidOwner' => $user
-		));
-
-		return true;
-	}
-
-	/**
-	 * Retrieve the owner of a connection
-	 *
-	 * @param IDBConnection $connection
-	 * @param int $shareId
-	 * @throws \Exception
-	 * @return string uid of share owner
-	 */
-	private static function getShareOwner(IDBConnection $connection, $shareId) {
-		$qb = $connection->getQueryBuilder();
-
-		$qb->select('uid_owner')
-			->from('share')
-			->where($qb->expr()->eq('id', $qb->createParameter('shareId')))
-			->setParameter(':shareId', $shareId);
-		$result = $qb->execute();
-		$result = $result->fetch();
-
-		if (empty($result)) {
-			throw new \Exception('Share not found');
-		}
-
-		return $result['uid_owner'];
-	}
-
-	/**
-	 * Set password for a public link share
-	 *
-	 * @param IUserSession $userSession
-	 * @param IDBConnection $connection
-	 * @param IConfig $config
-	 * @param int $shareId
-	 * @param string $password
-	 * @throws \Exception
-	 * @return boolean
-	 */
-	public static function setPassword(IUserSession $userSession,
-	                                   IDBConnection $connection,
-	                                   IConfig $config,
-	                                   $shareId, $password) {
-		$user = $userSession->getUser();
-		if (is_null($user)) {
-			throw new \Exception("User not logged in");
-		}
-
-		$uid = self::getShareOwner($connection, $shareId);
-
-		if ($uid !== $user->getUID()) {
-			throw new \Exception('Cannot update share of a different user');
-		}
-
-		if ($password === '') {
-			$password = null;
-		}
-
-		//If passwords are enforced the password can't be null
-		if (self::enforcePassword($config) && is_null($password)) {
-			throw new \Exception('Cannot remove password');
-		}
-
-		self::verifyPassword($password);
-
-		$qb = $connection->getQueryBuilder();
-		$qb->update('share')
-			->set('share_with', $qb->createParameter('pass'))
-			->where($qb->expr()->eq('id', $qb->createParameter('shareId')))
-			->setParameter(':pass', is_null($password) ? null : \OC::$server->getHasher()->hash($password))
-			->setParameter(':shareId', $shareId);
-
-		$qb->execute();
-
-		return true;
-	}
-
-	/**
-	 * Checks whether a share has expired, calls unshareItem() if yes.
-	 * @param array $item Share data (usually database row)
-	 * @return boolean True if item was expired, false otherwise.
-	 */
-	protected static function expireItem(array $item) {
-
-		$result = false;
-
-		// only use default expiration date for link shares
-		if ((int) $item['share_type'] === self::SHARE_TYPE_LINK) {
-
-			// calculate expiration date
-			if (!empty($item['expiration'])) {
-				$userDefinedExpire = new \DateTime($item['expiration']);
-				$expires = $userDefinedExpire->getTimestamp();
-			} else {
-				$expires = null;
-			}
-
-
-			// get default expiration settings
-			$defaultSettings = Helper::getDefaultExpireSetting();
-			$expires = Helper::calculateExpireDate($defaultSettings, $item['stime'], $expires);
-
-
-			if (is_int($expires)) {
-				$now = time();
-				if ($now > $expires) {
-					self::unshareItem($item);
-					$result = true;
-				}
-			}
-		}
-		return $result;
-	}
-
-	/**
-	 * Unshares a share given a share data array
-	 * @param array $item Share data (usually database row)
-	 * @param int $newParent parent ID
-	 * @return null
-	 */
-	protected static function unshareItem(array $item, $newParent = null) {
-
-		$shareType = (int)$item['share_type'];
-		$shareWith = null;
-		if ($shareType !== \OCP\Share::SHARE_TYPE_LINK) {
-			$shareWith = $item['share_with'];
-		}
-
-		// Pass all the vars we have for now, they may be useful
-		$hookParams = array(
-			'id'            => $item['id'],
-			'itemType'      => $item['item_type'],
-			'itemSource'    => $item['item_source'],
-			'shareType'     => $shareType,
-			'shareWith'     => $shareWith,
-			'itemParent'    => $item['parent'],
-			'uidOwner'      => $item['uid_owner'],
-		);
-		if($item['item_type'] === 'file' || $item['item_type'] === 'folder') {
-			$hookParams['fileSource'] = $item['file_source'];
-			$hookParams['fileTarget'] = $item['file_target'];
-		}
-
-		\OC_Hook::emit('OCP\Share', 'pre_unshare', $hookParams);
-		$deletedShares = Helper::delete($item['id'], false, null, $newParent);
-		$deletedShares[] = $hookParams;
-		$hookParams['deletedShares'] = $deletedShares;
-		\OC_Hook::emit('OCP\Share', 'post_unshare', $hookParams);
-		if ((int)$item['share_type'] === \OCP\Share::SHARE_TYPE_REMOTE && \OC::$server->getUserSession()->getUser()) {
-			list(, $remote) = Helper::splitUserRemote($item['share_with']);
-			self::sendRemoteUnshare($remote, $item['id'], $item['token']);
-		}
-	}
-
-	/**
-	 * Get the backend class for the specified item type
-	 * @param string $itemType
-	 * @throws \Exception
-	 * @return \OCP\Share_Backend
-	 */
-	public static function getBackend($itemType) {
-		$l = \OC::$server->getL10N('lib');
-		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 \OCP\Share_Backend)) {
-					$message = 'Sharing backend %s must implement the interface OCP\Share_Backend';
-					$message_t = $l->t('Sharing backend %s must implement the interface OCP\Share_Backend', array($class));
-					\OCP\Util::writeLog('OCP\Share', sprintf($message, $class), \OCP\Util::ERROR);
-					throw new \Exception($message_t);
-				}
-				return self::$backends[$itemType];
-			} else {
-				$message = 'Sharing backend %s not found';
-				$message_t = $l->t('Sharing backend %s not found', array($class));
-				\OCP\Util::writeLog('OCP\Share', sprintf($message, $class), \OCP\Util::ERROR);
-				throw new \Exception($message_t);
-			}
-		}
-		$message = 'Sharing backend for %s not found';
-		$message_t = $l->t('Sharing backend for %s not found', array($itemType));
-		\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemType), \OCP\Util::ERROR);
-		throw new \Exception($message_t);
-	}
-
-	/**
-	 * Check if resharing is allowed
-	 * @return boolean true if allowed or false
-	 *
-	 * Resharing is allowed by default if not configured
-	 */
-	public static function isResharingAllowed() {
-		if (!isset(self::$isResharingAllowed)) {
-			if (\OC::$server->getAppConfig()->getValue('core', 'shareapi_allow_resharing', 'yes') == 'yes') {
-				self::$isResharingAllowed = true;
-			} else {
-				self::$isResharingAllowed = false;
-			}
-		}
-		return self::$isResharingAllowed;
-	}
-
-	/**
-	 * Get a list of collection item types for the specified item type
-	 * @param string $itemType
-	 * @return array
-	 */
-	private static function getCollectionItemTypes($itemType) {
-		$collectionTypes = array($itemType);
-		foreach (self::$backendTypes as $type => $backend) {
-			if (in_array($backend['collectionOf'], $collectionTypes)) {
-				$collectionTypes[] = $type;
-			}
-		}
-		// TODO Add option for collections to be collection of themselves, only 'folder' does it now...
-		if (isset(self::$backendTypes[$itemType]) && (!self::getBackend($itemType) instanceof \OCP\Share_Backend_Collection || $itemType != 'folder')) {
-			unset($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;
-	}
-
-	/**
-	 * Get the owners of items shared with a user.
-	 *
-	 * @param string $user The user the items are shared with.
-	 * @param string $type The type of the items shared with the user.
-	 * @param boolean $includeCollections Include collection item types (optional)
-	 * @param boolean $includeOwner include owner in the list of users the item is shared with (optional)
-	 * @return array
-	 */
-	public static function getSharedItemsOwners($user, $type, $includeCollections = false, $includeOwner = false) {
-		// First, we find out if $type is part of a collection (and if that collection is part of
-		// another one and so on).
-		$collectionTypes = array();
-		if (!$includeCollections || !$collectionTypes = self::getCollectionItemTypes($type)) {
-			$collectionTypes[] = $type;
-		}
-
-		// Of these collection types, along with our original $type, we make a
-		// list of the ones for which a sharing backend has been registered.
-		// FIXME: Ideally, we wouldn't need to nest getItemsSharedWith in this loop but just call it
-		// with its $includeCollections parameter set to true. Unfortunately, this fails currently.
-		$allMaybeSharedItems = array();
-		foreach ($collectionTypes as $collectionType) {
-			if (isset(self::$backends[$collectionType])) {
-				$allMaybeSharedItems[$collectionType] = self::getItemsSharedWithUser(
-					$collectionType,
-					$user,
-					self::FORMAT_NONE
-				);
-			}
-		}
-
-		$owners = array();
-		if ($includeOwner) {
-			$owners[] = $user;
-		}
-
-		// We take a look at all shared items of the given $type (or of the collections it is part of)
-		// and find out their owners. Then, we gather the tags for the original $type from all owners,
-		// and return them as elements of a list that look like "Tag (owner)".
-		foreach ($allMaybeSharedItems as $collectionType => $maybeSharedItems) {
-			foreach ($maybeSharedItems as $sharedItem) {
-				if (isset($sharedItem['id'])) { //workaround for https://github.com/owncloud/core/issues/2814
-					$owners[] = $sharedItem['uid_owner'];
-				}
-			}
-		}
-
-		return $owners;
-	}
-
-	/**
-	 * Get shared items from the database
-	 * @param string $itemType
-	 * @param string $item Item source or target (optional)
-	 * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, SHARE_TYPE_LINK, $shareTypeUserAndGroups, or $shareTypeGroupUserUnique
-	 * @param string $shareWith User or group the item is being shared with
-	 * @param string $uidOwner User that is the owner of shared items (optional)
-	 * @param int $format Format to convert items to with formatItems() (optional)
-	 * @param mixed $parameters to pass to formatItems() (optional)
-	 * @param int $limit Number of items to return, -1 to return all matches (optional)
-	 * @param boolean $includeCollections Include collection item types (optional)
-	 * @param boolean $itemShareWithBySource (optional)
-	 * @param boolean $checkExpireDate
-	 * @return array
-	 *
-	 * See public functions getItem(s)... for parameter usage
-	 *
-	 */
-	public static function getItems($itemType, $item = null, $shareType = null, $shareWith = null,
-									$uidOwner = null, $format = self::FORMAT_NONE, $parameters = null, $limit = -1,
-									$includeCollections = false, $itemShareWithBySource = false, $checkExpireDate  = true) {
-		if (!self::isEnabled()) {
-			return array();
-		}
-		$backend = self::getBackend($itemType);
-		$collectionTypes = false;
-		// Get filesystem root to add it to the file target and remove from the
-		// file source, match file_source with the file cache
-		if ($itemType == 'file' || $itemType == 'folder') {
-			if(!is_null($uidOwner)) {
-				$root = \OC\Files\Filesystem::getRoot();
-			} else {
-				$root = '';
-			}
-			$where = 'INNER JOIN `*PREFIX*filecache` ON `file_source` = `*PREFIX*filecache`.`fileid` ';
-			if (!isset($item)) {
-				$where .= ' AND `file_target` IS NOT NULL ';
-			}
-			$where .= 'INNER JOIN `*PREFIX*storages` ON `numeric_id` = `*PREFIX*filecache`.`storage` ';
-			$fileDependent = true;
-			$queryArgs = array();
-		} else {
-			$fileDependent = false;
-			$root = '';
-			$collectionTypes = self::getCollectionItemTypes($itemType);
-			if ($includeCollections && !isset($item) && $collectionTypes) {
-				// If includeCollections is true, find collections of this item type, e.g. a music album contains songs
-				if (!in_array($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 (\OC::$server->getAppConfig()->getValue('core', 'shareapi_allow_links', 'yes') !== 'yes') {
-			$where .= ' AND `share_type` != ?';
-			$queryArgs[] = self::SHARE_TYPE_LINK;
-		}
-		if (isset($shareType)) {
-			// Include all user and group items
-			if ($shareType == self::$shareTypeUserAndGroups && isset($shareWith)) {
-				$where .= ' AND ((`share_type` in (?, ?) AND `share_with` = ?) ';
-				$queryArgs[] = self::SHARE_TYPE_USER;
-				$queryArgs[] = self::$shareTypeGroupUserUnique;
-				$queryArgs[] = $shareWith;
-
-				$user = \OC::$server->getUserManager()->get($shareWith);
-				$groups = [];
-				if ($user) {
-					$groups = \OC::$server->getGroupManager()->getUserGroupIds($user);
-				}
-				if (!empty($groups)) {
-					$placeholders = join(',', array_fill(0, count($groups), '?'));
-					$where .= ' OR (`share_type` = ? AND `share_with` IN ('.$placeholders.')) ';
-					$queryArgs[] = self::SHARE_TYPE_GROUP;
-					$queryArgs = array_merge($queryArgs, $groups);
-				}
-				$where .= ')';
-				// 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 ($fileDependent) {
-				$column = 'file_source';
-			} else {
-				$column = 'item_source';
-			}
-		} else {
-			if ($fileDependent) {
-				$column = 'file_target';
-			} else {
-				$column = 'item_target';
-			}
-		}
-		if (isset($item)) {
-			$collectionTypes = self::getCollectionItemTypes($itemType);
-			if ($includeCollections && $collectionTypes && !in_array('folder', $collectionTypes)) {
-				$where .= ' AND (';
-			} else {
-				$where .= ' AND';
-			}
-			// If looking for own shared items, check item_source else check item_target
-			if (isset($uidOwner) || $itemShareWithBySource) {
-				// If item type is a file, file source needs to be checked in case the item was converted
-				if ($fileDependent) {
-					$where .= ' `file_source` = ?';
-					$column = 'file_source';
-				} else {
-					$where .= ' `item_source` = ?';
-					$column = 'item_source';
-				}
-			} else {
-				if ($fileDependent) {
-					$where .= ' `file_target` = ?';
-					$item = \OC\Files\Filesystem::normalizePath($item);
-				} else {
-					$where .= ' `item_target` = ?';
-				}
-			}
-			$queryArgs[] = $item;
-			if ($includeCollections && $collectionTypes && !in_array('folder', $collectionTypes)) {
-				$placeholders = join(',', array_fill(0, count($collectionTypes), '?'));
-				$where .= ' OR `item_type` IN ('.$placeholders.'))';
-				$queryArgs = array_merge($queryArgs, $collectionTypes);
-			}
-		}
-
-		if ($shareType == self::$shareTypeUserAndGroups && $limit === 1) {
-			// 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';
-		} else {
-			$where .= ' ORDER BY `*PREFIX*share`.`id` ASC';
-		}
-
-		if ($limit != -1 && !$includeCollections) {
-			// The limit must be at least 3, because filtering needs to be done
-			if ($limit < 3) {
-				$queryLimit = 3;
-			} else {
-				$queryLimit = $limit;
-			}
-		} else {
-			$queryLimit = null;
-		}
-		$select = self::createSelectStatement($format, $fileDependent, $uidOwner);
-		$root = strlen($root);
-		$query = \OC_DB::prepare('SELECT '.$select.' FROM `*PREFIX*share` '.$where, $queryLimit);
-		$result = $query->execute($queryArgs);
-		if ($result === false) {
-			\OCP\Util::writeLog('OCP\Share',
-				\OC_DB::getErrorMessage() . ', select=' . $select . ' where=',
-				\OCP\Util::ERROR);
-		}
-		$items = array();
-		$targets = array();
-		$switchedItems = array();
-		$mounts = array();
-		while ($row = $result->fetchRow()) {
-			self::transformDBResults($row);
-			// Filter out duplicate group shares for users with unique targets
-			if ($fileDependent && !self::isFileReachable($row['path'], $row['storage_id'])) {
-				continue;
-			}
-			if ($row['share_type'] == self::$shareTypeGroupUserUnique && isset($items[$row['parent']])) {
-				$row['share_type'] = self::SHARE_TYPE_GROUP;
-				$row['unique_name'] = true; // remember that we use a unique name for this user
-				$row['share_with'] = $items[$row['parent']]['share_with'];
-				// if the group share was unshared from the user we keep the permission, otherwise
-				// we take the permission from the parent because this is always the up-to-date
-				// permission for the group share
-				if ($row['permissions'] > 0) {
-					$row['permissions'] = $items[$row['parent']]['permissions'];
-				}
-				// 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['id']])) {
-					// Check if the same owner shared with the user twice
-					// through a group and user share - this is allowed
-					$id = $targets[$row['id']];
-					if (isset($items[$id]) && $items[$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[$id]['permissions'] & \OCP\Constants::PERMISSION_SHARE
-							&& (int)$row['permissions'] & \OCP\Constants::PERMISSION_SHARE) {
-							$items[$row['id']] = $items[$id];
-							$switchedItems[$id] = $row['id'];
-							unset($items[$id]);
-							$id = $row['id'];
-						}
-						$items[$id]['permissions'] |= (int)$row['permissions'];
-
-					}
-					continue;
-				} elseif (!empty($row['parent'])) {
-					$targets[$row['parent']] = $row['id'];
-				}
-			}
-			// Remove root from file source paths if retrieving own shared items
-			if (isset($uidOwner) && isset($row['path'])) {
-				if (isset($row['parent'])) {
-					$query = \OC_DB::prepare('SELECT `file_target` FROM `*PREFIX*share` WHERE `id` = ?');
-					$parentResult = $query->execute(array($row['parent']));
-					if ($result === false) {
-						\OCP\Util::writeLog('OCP\Share', 'Can\'t select parent: ' .
-							\OC_DB::getErrorMessage() . ', select=' . $select . ' where=' . $where,
-							\OCP\Util::ERROR);
-					} else {
-						$parentRow = $parentResult->fetchRow();
-						$tmpPath = $parentRow['file_target'];
-						// find the right position where the row path continues from the target path
-						$pos = strrpos($row['path'], $parentRow['file_target']);
-						$subPath = substr($row['path'], $pos);
-						$splitPath = explode('/', $subPath);
-						foreach (array_slice($splitPath, 2) as $pathPart) {
-							$tmpPath = $tmpPath . '/' . $pathPart;
-						}
-						$row['path'] = $tmpPath;
-					}
-				} else {
-					if (!isset($mounts[$row['storage']])) {
-						$mountPoints = \OC\Files\Filesystem::getMountByNumericId($row['storage']);
-						if (is_array($mountPoints) && !empty($mountPoints)) {
-							$mounts[$row['storage']] = current($mountPoints);
-						}
-					}
-					if (!empty($mounts[$row['storage']])) {
-						$path = $mounts[$row['storage']]->getMountPoint().$row['path'];
-						$relPath = substr($path, $root); // path relative to data/user
-						$row['path'] = rtrim($relPath, '/');
-					}
-				}
-			}
-
-			if($checkExpireDate) {
-				if (self::expireItem($row)) {
-					continue;
-				}
-			}
-			// Check if resharing is allowed, if not remove share permission
-			if (isset($row['permissions']) && (!self::isResharingAllowed() | \OCP\Util::isSharingDisabledForUser())) {
-				$row['permissions'] &= ~\OCP\Constants::PERMISSION_SHARE;
-			}
-			// Add display names to result
-			$row['share_with_displayname'] = $row['share_with'];
-			if ( isset($row['share_with']) && $row['share_with'] != '' &&
-				$row['share_type'] === self::SHARE_TYPE_USER) {
-				$row['share_with_displayname'] = \OCP\User::getDisplayName($row['share_with']);
-			} else if(isset($row['share_with']) && $row['share_with'] != '' &&
-				$row['share_type'] === self::SHARE_TYPE_REMOTE) {
-				$addressBookEntries = \OC::$server->getContactsManager()->search($row['share_with'], ['CLOUD']);
-				foreach ($addressBookEntries as $entry) {
-					foreach ($entry['CLOUD'] as $cloudID) {
-						if ($cloudID === $row['share_with']) {
-							$row['share_with_displayname'] = $entry['FN'];
-						}
-					}
-				}
-			}
-			if ( isset($row['uid_owner']) && $row['uid_owner'] != '') {
-				$row['displayname_owner'] = \OCP\User::getDisplayName($row['uid_owner']);
-			}
-
-			if ($row['permissions'] > 0) {
-				$items[$row['id']] = $row;
-			}
-
-		}
-
-		// group items if we are looking for items shared with the current user
-		if (isset($shareWith) && $shareWith === \OCP\User::getUser()) {
-			$items = self::groupItems($items, $itemType);
-		}
-
-		if (!empty($items)) {
-			$collectionItems = array();
-			foreach ($items as &$row) {
-				// Return only the item instead of a 2-dimensional array
-				if ($limit == 1 && $row[$column] == $item && ($row['item_type'] == $itemType || $itemType == 'file')) {
-					if ($format == self::FORMAT_NONE) {
-						return $row;
-					} else {
-						break;
-					}
-				}
-				// Check if this is a collection of the requested item type
-				if ($includeCollections && $collectionTypes && $row['item_type'] !== 'folder' && in_array($row['item_type'], $collectionTypes)) {
-					if (($collectionBackend = self::getBackend($row['item_type']))
-						&& $collectionBackend instanceof \OCP\Share_Backend_Collection) {
-						// Collections can be inside collections, check if the item is a collection
-						if (isset($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 \OCP\Share_Backend_File_Dependent) {
-									if ($row['item_type'] == 'file' || $row['item_type'] == 'folder') {
-										$childItem['file_source'] = $child['source'];
-									} else { // TODO is this really needed if we already know that we use the file backend?
-										$meta = \OC\Files\Filesystem::getFileInfo($child['file_path']);
-										$childItem['file_source'] = $meta['fileid'];
-									}
-									$childItem['file_target'] =
-										\OC\Files\Filesystem::normalizePath($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
-					$toRemove = $row['id'];
-					if (array_key_exists($toRemove, $switchedItems)) {
-						$toRemove = $switchedItems[$toRemove];
-					}
-					unset($items[$toRemove]);
-				} elseif ($includeCollections && $collectionTypes && in_array($row['item_type'], $collectionTypes)) {
-					// FIXME: Thats a dirty hack to improve file sharing performance,
-					// see github issue #10588 for more details
-					// Need to find a solution which works for all back-ends
-					$collectionBackend = self::getBackend($row['item_type']);
-					$sharedParents = $collectionBackend->getParents($row['item_source']);
-					foreach ($sharedParents as $parent) {
-						$collectionItems[] = $parent;
-					}
-				}
-			}
-			if (!empty($collectionItems)) {
-				$collectionItems = array_unique($collectionItems, SORT_REGULAR);
-				$items = array_merge($items, $collectionItems);
-			}
-
-			// filter out invalid items, these can appear when subshare entries exist
-			// for a group in which the requested user isn't a member any more
-			$items = array_filter($items, function($item) {
-				return $item['share_type'] !== self::$shareTypeGroupUserUnique;
-			});
-
-			return self::formatResult($items, $column, $backend, $format, $parameters);
-		} elseif ($includeCollections && $collectionTypes && in_array('folder', $collectionTypes)) {
-			// FIXME: Thats a dirty hack to improve file sharing performance,
-			// see github issue #10588 for more details
-			// Need to find a solution which works for all back-ends
-			$collectionItems = array();
-			$collectionBackend = self::getBackend('folder');
-			$sharedParents = $collectionBackend->getParents($item, $shareWith, $uidOwner);
-			foreach ($sharedParents as $parent) {
-				$collectionItems[] = $parent;
-			}
-			if ($limit === 1) {
-				return reset($collectionItems);
-			}
-			return self::formatResult($collectionItems, $column, $backend, $format, $parameters);
-		}
-
-		return array();
-	}
-
-	/**
-	 * group items with link to the same source
-	 *
-	 * @param array $items
-	 * @param string $itemType
-	 * @return array of grouped items
-	 */
-	protected static function groupItems($items, $itemType) {
-
-		$fileSharing = ($itemType === 'file' || $itemType === 'folder') ? true : false;
-
-		$result = array();
-
-		foreach ($items as $item) {
-			$grouped = false;
-			foreach ($result as $key => $r) {
-				// for file/folder shares we need to compare file_source, otherwise we compare item_source
-				// only group shares if they already point to the same target, otherwise the file where shared
-				// before grouping of shares was added. In this case we don't group them toi avoid confusions
-				if (( $fileSharing && $item['file_source'] === $r['file_source'] && $item['file_target'] === $r['file_target']) ||
-					(!$fileSharing && $item['item_source'] === $r['item_source'] && $item['item_target'] === $r['item_target'])) {
-					// add the first item to the list of grouped shares
-					if (!isset($result[$key]['grouped'])) {
-						$result[$key]['grouped'][] = $result[$key];
-					}
-					$result[$key]['permissions'] = (int) $item['permissions'] | (int) $r['permissions'];
-					$result[$key]['grouped'][] = $item;
-					$grouped = true;
-					break;
-				}
-			}
-
-			if (!$grouped) {
-				$result[] = $item;
-			}
-
-		}
-
-		return $result;
-	}
-
-	/**
-	 * Put shared item into the database
-	 * @param string $itemType Item type
-	 * @param string $itemSource Item source
-	 * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
-	 * @param string $shareWith User or group the item is being shared with
-	 * @param string $uidOwner User that is the owner of shared item
-	 * @param int $permissions CRUDS permissions
-	 * @param boolean|array $parentFolder Parent folder target (optional)
-	 * @param string $token (optional)
-	 * @param string $itemSourceName name of the source item (optional)
-	 * @param \DateTime $expirationDate (optional)
-	 * @throws \Exception
-	 * @return mixed id of the new share or false
-	 */
-	private static function put($itemType, $itemSource, $shareType, $shareWith, $uidOwner,
-								$permissions, $parentFolder = null, $token = null, $itemSourceName = null, \DateTime $expirationDate = null) {
-
-		$queriesToExecute = array();
-		$suggestedItemTarget = null;
-		$groupFileTarget = $fileTarget = $suggestedFileTarget = $filePath = '';
-		$groupItemTarget = $itemTarget = $fileSource = $parent = 0;
-
-		$result = self::checkReshare($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, $itemSourceName, $expirationDate);
-		if(!empty($result)) {
-			$parent = $result['parent'];
-			$itemSource = $result['itemSource'];
-			$fileSource = $result['fileSource'];
-			$suggestedItemTarget = $result['suggestedItemTarget'];
-			$suggestedFileTarget = $result['suggestedFileTarget'];
-			$filePath = $result['filePath'];
-		}
-
-		$isGroupShare = false;
-		if ($shareType == self::SHARE_TYPE_GROUP) {
-			$isGroupShare = true;
-			if (isset($shareWith['users'])) {
-				$users = $shareWith['users'];
-			} else {
-				$group = \OC::$server->getGroupManager()->get($shareWith['group']);
-				if ($group) {
-					$users = $group->searchUsers('', -1, 0);
-					$userIds = [];
-					foreach ($users as $user) {
-						$userIds[] = $user->getUID();
-					}
-					$users = $userIds;
-				} else {
-					$users = [];
-				}
-			}
-			// remove current user from list
-			if (in_array(\OCP\User::getUser(), $users)) {
-				unset($users[array_search(\OCP\User::getUser(), $users)]);
-			}
-			$groupItemTarget = Helper::generateTarget($itemType, $itemSource,
-				$shareType, $shareWith['group'], $uidOwner, $suggestedItemTarget);
-			$groupFileTarget = Helper::generateTarget($itemType, $itemSource,
-				$shareType, $shareWith['group'], $uidOwner, $filePath);
-
-			// add group share to table and remember the id as parent
-			$queriesToExecute['groupShare'] = array(
-				'itemType'			=> $itemType,
-				'itemSource'		=> $itemSource,
-				'itemTarget'		=> $groupItemTarget,
-				'shareType'			=> $shareType,
-				'shareWith'			=> $shareWith['group'],
-				'uidOwner'			=> $uidOwner,
-				'permissions'		=> $permissions,
-				'shareTime'			=> time(),
-				'fileSource'		=> $fileSource,
-				'fileTarget'		=> $groupFileTarget,
-				'token'				=> $token,
-				'parent'			=> $parent,
-				'expiration'		=> $expirationDate,
-			);
-
-		} else {
-			$users = array($shareWith);
-			$itemTarget = Helper::generateTarget($itemType, $itemSource, $shareType, $shareWith, $uidOwner,
-				$suggestedItemTarget);
-		}
-
-		$run = true;
-		$error = '';
-		$preHookData = array(
-			'itemType' => $itemType,
-			'itemSource' => $itemSource,
-			'shareType' => $shareType,
-			'uidOwner' => $uidOwner,
-			'permissions' => $permissions,
-			'fileSource' => $fileSource,
-			'expiration' => $expirationDate,
-			'token' => $token,
-			'run' => &$run,
-			'error' => &$error
-		);
-
-		$preHookData['itemTarget'] = ($isGroupShare) ? $groupItemTarget : $itemTarget;
-		$preHookData['shareWith'] = ($isGroupShare) ? $shareWith['group'] : $shareWith;
-
-		\OC_Hook::emit('OCP\Share', 'pre_shared', $preHookData);
-
-		if ($run === false) {
-			throw new \Exception($error);
-		}
-
-		foreach ($users as $user) {
-			$sourceId = ($itemType === 'file' || $itemType === 'folder') ? $fileSource : $itemSource;
-			$sourceExists = self::getItemSharedWithBySource($itemType, $sourceId, self::FORMAT_NONE, null, true, $user);
-
-			$userShareType = ($isGroupShare) ? self::$shareTypeGroupUserUnique : $shareType;
-
-			if ($sourceExists && $sourceExists['item_source'] === $itemSource) {
-				$fileTarget = $sourceExists['file_target'];
-				$itemTarget = $sourceExists['item_target'];
-
-				// for group shares we don't need a additional entry if the target is the same
-				if($isGroupShare && $groupItemTarget === $itemTarget) {
-					continue;
-				}
-
-			} elseif(!$sourceExists && !$isGroupShare)  {
-
-				$itemTarget = Helper::generateTarget($itemType, $itemSource, $userShareType, $user,
-					$uidOwner, $suggestedItemTarget, $parent);
-				if (isset($fileSource)) {
-					if ($parentFolder) {
-						if ($parentFolder === true) {
-							$fileTarget = Helper::generateTarget('file', $filePath, $userShareType, $user,
-								$uidOwner, $suggestedFileTarget, $parent);
-							if ($fileTarget != $groupFileTarget) {
-								$parentFolders[$user]['folder'] = $fileTarget;
-							}
-						} else if (isset($parentFolder[$user])) {
-							$fileTarget = $parentFolder[$user]['folder'].$itemSource;
-							$parent = $parentFolder[$user]['id'];
-						}
-					} else {
-						$fileTarget = Helper::generateTarget('file', $filePath, $userShareType,
-							$user, $uidOwner, $suggestedFileTarget, $parent);
-					}
-				} else {
-					$fileTarget = null;
-				}
-
-			} else {
-
-				// group share which doesn't exists until now, check if we need a unique target for this user
-
-				$itemTarget = Helper::generateTarget($itemType, $itemSource, self::SHARE_TYPE_USER, $user,
-					$uidOwner, $suggestedItemTarget, $parent);
-
-				// do we also need a file target
-				if (isset($fileSource)) {
-					$fileTarget = Helper::generateTarget('file', $filePath, self::SHARE_TYPE_USER, $user,
-						$uidOwner, $suggestedFileTarget, $parent);
-				} else {
-					$fileTarget = null;
-				}
-
-				if (($itemTarget === $groupItemTarget) &&
-					(!isset($fileSource) || $fileTarget === $groupFileTarget)) {
-					continue;
-				}
-			}
-
-			$queriesToExecute[] = array(
-				'itemType'			=> $itemType,
-				'itemSource'		=> $itemSource,
-				'itemTarget'		=> $itemTarget,
-				'shareType'			=> $userShareType,
-				'shareWith'			=> $user,
-				'uidOwner'			=> $uidOwner,
-				'permissions'		=> $permissions,
-				'shareTime'			=> time(),
-				'fileSource'		=> $fileSource,
-				'fileTarget'		=> $fileTarget,
-				'token'				=> $token,
-				'parent'			=> $parent,
-				'expiration'		=> $expirationDate,
-			);
-
-		}
-
-		$id = false;
-		if ($isGroupShare) {
-			$id = self::insertShare($queriesToExecute['groupShare']);
-			// Save this id, any extra rows for this group share will need to reference it
-			$parent = \OC::$server->getDatabaseConnection()->lastInsertId('*PREFIX*share');
-			unset($queriesToExecute['groupShare']);
-		}
-
-		foreach ($queriesToExecute as $shareQuery) {
-			$shareQuery['parent'] = $parent;
-			$id = self::insertShare($shareQuery);
-		}
-
-		$postHookData = array(
-			'itemType' => $itemType,
-			'itemSource' => $itemSource,
-			'parent' => $parent,
-			'shareType' => $shareType,
-			'uidOwner' => $uidOwner,
-			'permissions' => $permissions,
-			'fileSource' => $fileSource,
-			'id' => $parent,
-			'token' => $token,
-			'expirationDate' => $expirationDate,
-		);
-
-		$postHookData['shareWith'] = ($isGroupShare) ? $shareWith['group'] : $shareWith;
-		$postHookData['itemTarget'] = ($isGroupShare) ? $groupItemTarget : $itemTarget;
-		$postHookData['fileTarget'] = ($isGroupShare) ? $groupFileTarget : $fileTarget;
-
-		\OC_Hook::emit('OCP\Share', 'post_shared', $postHookData);
-
-
-		return $id ? $id : false;
-	}
-
-	/**
-	 * @param string $itemType
-	 * @param string $itemSource
-	 * @param int $shareType
-	 * @param string $shareWith
-	 * @param string $uidOwner
-	 * @param int $permissions
-	 * @param string|null $itemSourceName
-	 * @param null|\DateTime $expirationDate
-	 */
-	private static function checkReshare($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, $itemSourceName, $expirationDate) {
-		$backend = self::getBackend($itemType);
-
-		$l = \OC::$server->getL10N('lib');
-		$result = array();
-
-		$column = ($itemType === 'file' || $itemType === 'folder') ? 'file_source' : 'item_source';
-
-		$checkReshare = self::getItemSharedWithBySource($itemType, $itemSource, self::FORMAT_NONE, null, true);
-		if ($checkReshare) {
-			// Check if attempting to share back to owner
-			if ($checkReshare['uid_owner'] == $shareWith && $shareType == self::SHARE_TYPE_USER) {
-				$message = 'Sharing %s failed, because the user %s is the original sharer';
-				$message_t = $l->t('Sharing failed, because the user %s is the original sharer', [$shareWith]);
-
-				\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
-				throw new \Exception($message_t);
-			}
-		}
-
-		if ($checkReshare && $checkReshare['uid_owner'] !== \OC_User::getUser()) {
-			// Check if share permissions is granted
-			if (self::isResharingAllowed() && (int)$checkReshare['permissions'] & \OCP\Constants::PERMISSION_SHARE) {
-				if (~(int)$checkReshare['permissions'] & $permissions) {
-					$message = 'Sharing %s failed, because the permissions exceed permissions granted to %s';
-					$message_t = $l->t('Sharing %s failed, because the permissions exceed permissions granted to %s', array($itemSourceName, $uidOwner));
-
-					\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $uidOwner), \OCP\Util::DEBUG);
-					throw new \Exception($message_t);
-				} else {
-					// TODO Don't check if inside folder
-					$result['parent'] = $checkReshare['id'];
-
-					$result['expirationDate'] = $expirationDate;
-					// $checkReshare['expiration'] could be null and then is always less than any value
-					if(isset($checkReshare['expiration']) && $checkReshare['expiration'] < $expirationDate) {
-						$result['expirationDate'] = $checkReshare['expiration'];
-					}
-
-					// only suggest the same name as new target if it is a reshare of the
-					// same file/folder and not the reshare of a child
-					if ($checkReshare[$column] === $itemSource) {
-						$result['filePath'] = $checkReshare['file_target'];
-						$result['itemSource'] = $checkReshare['item_source'];
-						$result['fileSource'] = $checkReshare['file_source'];
-						$result['suggestedItemTarget'] = $checkReshare['item_target'];
-						$result['suggestedFileTarget'] = $checkReshare['file_target'];
-					} else {
-						$result['filePath'] = ($backend instanceof \OCP\Share_Backend_File_Dependent) ? $backend->getFilePath($itemSource, $uidOwner) : null;
-						$result['suggestedItemTarget'] = null;
-						$result['suggestedFileTarget'] = null;
-						$result['itemSource'] = $itemSource;
-						$result['fileSource'] = ($backend instanceof \OCP\Share_Backend_File_Dependent) ? $itemSource : null;
-					}
-				}
-			} else {
-				$message = 'Sharing %s failed, because resharing is not allowed';
-				$message_t = $l->t('Sharing %s failed, because resharing is not allowed', array($itemSourceName));
-
-				\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName), \OCP\Util::DEBUG);
-				throw new \Exception($message_t);
-			}
-		} else {
-			$result['parent'] = null;
-			$result['suggestedItemTarget'] = null;
-			$result['suggestedFileTarget'] = null;
-			$result['itemSource'] = $itemSource;
-			$result['expirationDate'] = $expirationDate;
-			if (!$backend->isValidSource($itemSource, $uidOwner)) {
-				$message = 'Sharing %s failed, because the sharing backend for '
-					.'%s could not find its source';
-				$message_t = $l->t('Sharing %s failed, because the sharing backend for %s could not find its source', array($itemSource, $itemType));
-				\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSource, $itemType), \OCP\Util::DEBUG);
-				throw new \Exception($message_t);
-			}
-			if ($backend instanceof \OCP\Share_Backend_File_Dependent) {
-				$result['filePath'] = $backend->getFilePath($itemSource, $uidOwner);
-				if ($itemType == 'file' || $itemType == 'folder') {
-					$result['fileSource'] = $itemSource;
-				} else {
-					$meta = \OC\Files\Filesystem::getFileInfo($result['filePath']);
-					$result['fileSource'] = $meta['fileid'];
-				}
-				if ($result['fileSource'] == -1) {
-					$message = 'Sharing %s failed, because the file could not be found in the file cache';
-					$message_t = $l->t('Sharing %s failed, because the file could not be found in the file cache', array($itemSource));
-
-					\OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSource), \OCP\Util::DEBUG);
-					throw new \Exception($message_t);
-				}
-			} else {
-				$result['filePath'] = null;
-				$result['fileSource'] = null;
-			}
-		}
-
-		return $result;
-	}
-
-	/**
-	 *
-	 * @param array $shareData
-	 * @return mixed false in case of a failure or the id of the new share
-	 */
-	private static function insertShare(array $shareData) {
-
-		$query = \OC_DB::prepare('INSERT INTO `*PREFIX*share` ('
-			.' `item_type`, `item_source`, `item_target`, `share_type`,'
-			.' `share_with`, `uid_owner`, `permissions`, `stime`, `file_source`,'
-			.' `file_target`, `token`, `parent`, `expiration`) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?)');
-		$query->bindValue(1, $shareData['itemType']);
-		$query->bindValue(2, $shareData['itemSource']);
-		$query->bindValue(3, $shareData['itemTarget']);
-		$query->bindValue(4, $shareData['shareType']);
-		$query->bindValue(5, $shareData['shareWith']);
-		$query->bindValue(6, $shareData['uidOwner']);
-		$query->bindValue(7, $shareData['permissions']);
-		$query->bindValue(8, $shareData['shareTime']);
-		$query->bindValue(9, $shareData['fileSource']);
-		$query->bindValue(10, $shareData['fileTarget']);
-		$query->bindValue(11, $shareData['token']);
-		$query->bindValue(12, $shareData['parent']);
-		$query->bindValue(13, $shareData['expiration'], 'datetime');
-		$result = $query->execute();
-
-		$id = false;
-		if ($result) {
-			$id =  \OC::$server->getDatabaseConnection()->lastInsertId('*PREFIX*share');
-		}
-
-		return $id;
-
-	}
-
-	/**
-	 * Delete all shares with type SHARE_TYPE_LINK
-	 */
-	public static function removeAllLinkShares() {
-		// Delete any link shares
-		$query = \OC_DB::prepare('SELECT `id` FROM `*PREFIX*share` WHERE `share_type` = ?');
-		$result = $query->execute(array(self::SHARE_TYPE_LINK));
-		while ($item = $result->fetchRow()) {
-			Helper::delete($item['id']);
-		}
-	}
-
-	/**
-	 * In case a password protected link is not yet authenticated this function will return false
-	 *
-	 * @param array $linkItem
-	 * @return boolean
-	 */
-	public static function checkPasswordProtectedShare(array $linkItem) {
-		if (!isset($linkItem['share_with'])) {
-			return true;
-		}
-		if (!isset($linkItem['share_type'])) {
-			return true;
-		}
-		if (!isset($linkItem['id'])) {
-			return true;
-		}
-
-		if ($linkItem['share_type'] != \OCP\Share::SHARE_TYPE_LINK) {
-			return true;
-		}
-
-		if ( \OC::$server->getSession()->exists('public_link_authenticated')
-			&& \OC::$server->getSession()->get('public_link_authenticated') === (string)$linkItem['id'] ) {
-			return true;
-		}
-
-		return false;
-	}
-
-	/**
-	 * construct select statement
-	 * @param int $format
-	 * @param boolean $fileDependent ist it a file/folder share or a generla share
-	 * @param string $uidOwner
-	 * @return string select statement
-	 */
-	private static function createSelectStatement($format, $fileDependent, $uidOwner = null) {
-		$select = '*';
-		if ($format == self::FORMAT_STATUSES) {
-			if ($fileDependent) {
-				$select = '`*PREFIX*share`.`id`, `*PREFIX*share`.`parent`, `share_type`, `path`, `storage`, '
-					. '`share_with`, `uid_owner` , `file_source`, `stime`, `*PREFIX*share`.`permissions`, '
-					. '`*PREFIX*storages`.`id` AS `storage_id`, `*PREFIX*filecache`.`parent` as `file_parent`, '
-					. '`uid_initiator`';
-			} else {
-				$select = '`id`, `parent`, `share_type`, `share_with`, `uid_owner`, `item_source`, `stime`, `*PREFIX*share`.`permissions`';
-			}
-		} else {
-			if (isset($uidOwner)) {
-				if ($fileDependent) {
-					$select = '`*PREFIX*share`.`id`, `item_type`, `item_source`, `*PREFIX*share`.`parent`,'
-						. ' `share_type`, `share_with`, `file_source`, `file_target`, `path`, `*PREFIX*share`.`permissions`, `stime`,'
-						. ' `expiration`, `token`, `storage`, `mail_send`, `uid_owner`, '
-						. '`*PREFIX*storages`.`id` AS `storage_id`, `*PREFIX*filecache`.`parent` as `file_parent`';
-				} else {
-					$select = '`id`, `item_type`, `item_source`, `parent`, `share_type`, `share_with`, `*PREFIX*share`.`permissions`,'
-						. ' `stime`, `file_source`, `expiration`, `token`, `mail_send`, `uid_owner`';
-				}
-			} else {
-				if ($fileDependent) {
-					if ($format == \OCA\Files_Sharing\ShareBackend\File::FORMAT_GET_FOLDER_CONTENTS || $format == \OCA\Files_Sharing\ShareBackend\File::FORMAT_FILE_APP_ROOT) {
-						$select = '`*PREFIX*share`.`id`, `item_type`, `item_source`, `*PREFIX*share`.`parent`, `uid_owner`, '
-							. '`share_type`, `share_with`, `file_source`, `path`, `file_target`, `stime`, '
-							. '`*PREFIX*share`.`permissions`, `expiration`, `storage`, `*PREFIX*filecache`.`parent` as `file_parent`, '
-							. '`name`, `mtime`, `mimetype`, `mimepart`, `size`, `encrypted`, `etag`, `mail_send`';
-					} 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`, `*PREFIX*share`.`permissions`,'
-						    . '`stime`, `expiration`, `token`, `storage`, `mail_send`,'
-							. '`*PREFIX*storages`.`id` AS `storage_id`, `*PREFIX*filecache`.`parent` as `file_parent`';
-					}
-				}
-			}
-		}
-		return $select;
-	}
-
-
-	/**
-	 * transform db results
-	 * @param array $row result
-	 */
-	private static function transformDBResults(&$row) {
-		if (isset($row['id'])) {
-			$row['id'] = (int) $row['id'];
-		}
-		if (isset($row['share_type'])) {
-			$row['share_type'] = (int) $row['share_type'];
-		}
-		if (isset($row['parent'])) {
-			$row['parent'] = (int) $row['parent'];
-		}
-		if (isset($row['file_parent'])) {
-			$row['file_parent'] = (int) $row['file_parent'];
-		}
-		if (isset($row['file_source'])) {
-			$row['file_source'] = (int) $row['file_source'];
-		}
-		if (isset($row['permissions'])) {
-			$row['permissions'] = (int) $row['permissions'];
-		}
-		if (isset($row['storage'])) {
-			$row['storage'] = (int) $row['storage'];
-		}
-		if (isset($row['stime'])) {
-			$row['stime'] = (int) $row['stime'];
-		}
-		if (isset($row['expiration']) && $row['share_type'] !== self::SHARE_TYPE_LINK) {
-			// discard expiration date for non-link shares, which might have been
-			// set by ancient bugs
-			$row['expiration'] = null;
-		}
-	}
-
-	/**
-	 * format result
-	 * @param array $items result
-	 * @param string $column is it a file share or a general share ('file_target' or 'item_target')
-	 * @param \OCP\Share_Backend $backend sharing backend
-	 * @param int $format
-	 * @param array $parameters additional format parameters
-	 * @return array format result
-	 */
-	private static function formatResult($items, $column, $backend, $format = self::FORMAT_NONE , $parameters = null) {
-		if ($format === self::FORMAT_NONE) {
-			return $items;
-		} else if ($format === self::FORMAT_STATUSES) {
-			$statuses = array();
-			foreach ($items as $item) {
-				if ($item['share_type'] === self::SHARE_TYPE_LINK) {
-					if ($item['uid_initiator'] !== \OC::$server->getUserSession()->getUser()->getUID()) {
-						continue;
-					}
-					$statuses[$item[$column]]['link'] = true;
-				} else if (!isset($statuses[$item[$column]])) {
-					$statuses[$item[$column]]['link'] = false;
-				}
-				if (!empty($item['file_target'])) {
-					$statuses[$item[$column]]['path'] = $item['path'];
-				}
-			}
-			return $statuses;
-		} else {
-			return $backend->formatItems($items, $format, $parameters);
-		}
-	}
-
-	/**
-	 * remove protocol from URL
-	 *
-	 * @param string $url
-	 * @return string
-	 */
-	public static function removeProtocolFromUrl($url) {
-		if (strpos($url, 'https://') === 0) {
-			return substr($url, strlen('https://'));
-		} else if (strpos($url, 'http://') === 0) {
-			return substr($url, strlen('http://'));
-		}
-
-		return $url;
-	}
-
-	/**
-	 * try http post first with https and then with http as a fallback
-	 *
-	 * @param string $remoteDomain
-	 * @param string $urlSuffix
-	 * @param array $fields post parameters
-	 * @return array
-	 */
-	private static function tryHttpPostToShareEndpoint($remoteDomain, $urlSuffix, array $fields) {
-		$protocol = 'https://';
-		$result = [
-			'success' => false,
-			'result' => '',
-		];
-		$try = 0;
-		$discoveryService = \OC::$server->query(\OCP\OCS\IDiscoveryService::class);
-		while ($result['success'] === false && $try < 2) {
-			$federationEndpoints = $discoveryService->discover($protocol . $remoteDomain, 'FEDERATED_SHARING');
-			$endpoint = isset($federationEndpoints['share']) ? $federationEndpoints['share'] : '/ocs/v2.php/cloud/shares';
-			$result = \OC::$server->getHTTPHelper()->post($protocol . $remoteDomain . $endpoint . $urlSuffix . '?format=' . self::RESPONSE_FORMAT, $fields);
-			$try++;
-			$protocol = 'http://';
-		}
-
-		return $result;
-	}
-
-	/**
-	 * send server-to-server share to remote server
-	 *
-	 * @param string $token
-	 * @param string $shareWith
-	 * @param string $name
-	 * @param int $remote_id
-	 * @param string $owner
-	 * @return bool
-	 */
-	private static function sendRemoteShare($token, $shareWith, $name, $remote_id, $owner) {
-
-		list($user, $remote) = Helper::splitUserRemote($shareWith);
-
-		if ($user && $remote) {
-			$url = $remote;
-
-			$local = \OC::$server->getURLGenerator()->getAbsoluteURL('/');
-
-			$fields = array(
-				'shareWith' => $user,
-				'token' => $token,
-				'name' => $name,
-				'remoteId' => $remote_id,
-				'owner' => $owner,
-				'remote' => $local,
-			);
-
-			$url = self::removeProtocolFromUrl($url);
-			$result = self::tryHttpPostToShareEndpoint($url, '', $fields);
-			$status = json_decode($result['result'], true);
-
-			if ($result['success'] && ($status['ocs']['meta']['statuscode'] === 100 || $status['ocs']['meta']['statuscode'] === 200)) {
-				\OC_Hook::emit('OCP\Share', 'federated_share_added', ['server' => $remote]);
-				return true;
-			}
-
-		}
-
-		return false;
-	}
-
-	/**
-	 * send server-to-server unshare to remote server
-	 *
-	 * @param string $remote url
-	 * @param int $id share id
-	 * @param string $token
-	 * @return bool
-	 */
-	private static function sendRemoteUnshare($remote, $id, $token) {
-		$url = rtrim($remote, '/');
-		$fields = array('token' => $token, 'format' => 'json');
-		$url = self::removeProtocolFromUrl($url);
-		$result = self::tryHttpPostToShareEndpoint($url, '/'.$id.'/unshare', $fields);
-		$status = json_decode($result['result'], true);
-
-		return ($result['success'] && ($status['ocs']['meta']['statuscode'] === 100 || $status['ocs']['meta']['statuscode'] === 200));
-	}
-
-	/**
-	 * check if user can only share with group members
-	 * @return bool
-	 */
-	public static function shareWithGroupMembersOnly() {
-		$value = \OC::$server->getAppConfig()->getValue('core', 'shareapi_only_share_with_group_members', 'no');
-		return ($value === 'yes') ? true : false;
-	}
-
-	/**
-	 * @return bool
-	 */
-	public static function isDefaultExpireDateEnabled() {
-		$defaultExpireDateEnabled = \OCP\Config::getAppValue('core', 'shareapi_default_expire_date', 'no');
-		return ($defaultExpireDateEnabled === "yes") ? true : false;
-	}
-
-	/**
-	 * @return bool
-	 */
-	public static function enforceDefaultExpireDate() {
-		$enforceDefaultExpireDate = \OCP\Config::getAppValue('core', 'shareapi_enforce_expire_date', 'no');
-		return ($enforceDefaultExpireDate === "yes") ? true : false;
-	}
-
-	/**
-	 * @return int
-	 */
-	public static function getExpireInterval() {
-		return (int)\OCP\Config::getAppValue('core', 'shareapi_expire_after_n_days', '7');
-	}
-
-	/**
-	 * Checks whether the given path is reachable for the given owner
-	 *
-	 * @param string $path path relative to files
-	 * @param string $ownerStorageId storage id of the owner
-	 *
-	 * @return boolean true if file is reachable, false otherwise
-	 */
-	private static function isFileReachable($path, $ownerStorageId) {
-		// if outside the home storage, file is always considered reachable
-		if (!(substr($ownerStorageId, 0, 6) === 'home::' ||
-			substr($ownerStorageId, 0, 13) === 'object::user:'
-		)) {
-			return true;
-		}
-
-		// if inside the home storage, the file has to be under "/files/"
-		$path = ltrim($path, '/');
-		if (substr($path, 0, 6) === 'files/') {
-			return true;
-		}
-
-		return false;
-	}
-
-	/**
-	 * @param IConfig $config
-	 * @return bool
-	 */
-	public static function enforcePassword(IConfig $config) {
-		$enforcePassword = $config->getAppValue('core', 'shareapi_enforce_links_password', 'no');
-		return ($enforcePassword === "yes") ? true : false;
-	}
-
-	/**
-	 * Get all share entries, including non-unique group items
-	 *
-	 * @param string $owner
-	 * @return array
-	 */
-	public static function getAllSharesForOwner($owner) {
-		$query = 'SELECT * FROM `*PREFIX*share` WHERE `uid_owner` = ?';
-		$result = \OC::$server->getDatabaseConnection()->executeQuery($query, [$owner]);
-		return $result->fetchAll();
-	}
-
-	/**
-	 * Get all share entries, including non-unique group items for a file
-	 *
-	 * @param int $id
-	 * @return array
-	 */
-	public static function getAllSharesForFileId($id) {
-		$query = 'SELECT * FROM `*PREFIX*share` WHERE `file_source` = ?';
-		$result = \OC::$server->getDatabaseConnection()->executeQuery($query, [$id]);
-		return $result->fetchAll();
-	}
-
-	/**
-	 * @param string $password
-	 * @throws \Exception
-	 */
-	private static function verifyPassword($password) {
-
-		$accepted = true;
-		$message = '';
-		\OCP\Util::emitHook('\OC\Share', 'verifyPassword', [
-			'password' => $password,
-			'accepted' => &$accepted,
-			'message' => &$message
-		]);
-
-		if (!$accepted) {
-			throw new \Exception($message);
-		}
-	}
+            if ($permissions & ~(int)$rootItem['permissions']) {
+                $qb = $connection->getQueryBuilder();
+                $qb->select('id', 'permissions', 'item_type')
+                    ->from('share')
+                    ->where($qb->expr()->eq('parent', $qb->createParameter('parent')))
+                    ->andWhere($qb->expr()->eq('share_type', $qb->createParameter('share_type')))
+                    ->andWhere($qb->expr()->neq('permissions', $qb->createParameter('shareDeleted')))
+                    ->setParameter(':parent', (int)$rootItem['id'])
+                    ->setParameter(':share_type', 2)
+                    ->setParameter(':shareDeleted', 0);
+                $result = $qb->execute();
+
+                $ids = [];
+                while ($item = $result->fetch()) {
+                    $item = $sanitizeItem($item);
+                    $items[] = $item;
+                    $ids[] = $item['id'];
+                }
+                $result->closeCursor();
+
+                // Add permssions for all USERGROUP shares of this item
+                if (!empty($ids)) {
+                    $ids = $intArrayToLiteralArray($ids, $qb->expr());
+
+                    $qb = $connection->getQueryBuilder();
+                    $qb->update('share')
+                        ->set('permissions', $qb->createParameter('permissions'))
+                        ->where($qb->expr()->in('id', $ids))
+                        ->setParameter(':permissions', $permissions);
+                    $qb->execute();
+                }
+            }
+
+            foreach ($items as $item) {
+                \OC_Hook::emit('OCP\Share', 'post_update_permissions', ['share' => $item]);
+            }
+
+            return true;
+        }
+        $message = 'Setting permissions for %s failed, because the item was not found';
+        $message_t = $l->t('Setting permissions for %s failed, because the item was not found', array($itemSource));
+
+        \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSource), \OCP\Util::DEBUG);
+        throw new \Exception($message_t);
+    }
+
+    /**
+     * validate expiration date if it meets all constraints
+     *
+     * @param string $expireDate well formatted date string, e.g. "DD-MM-YYYY"
+     * @param string $shareTime timestamp when the file was shared
+     * @param string $itemType
+     * @param string $itemSource
+     * @return \DateTime validated date
+     * @throws \Exception when the expire date is in the past or further in the future then the enforced date
+     */
+    private static function validateExpireDate($expireDate, $shareTime, $itemType, $itemSource) {
+        $l = \OC::$server->getL10N('lib');
+        $date = new \DateTime($expireDate);
+        $today = new \DateTime('now');
+
+        // if the user doesn't provide a share time we need to get it from the database
+        // fall-back mode to keep API stable, because the $shareTime parameter was added later
+        $defaultExpireDateEnforced = \OCP\Util::isDefaultExpireDateEnforced();
+        if ($defaultExpireDateEnforced && $shareTime === null) {
+            $items = self::getItemShared($itemType, $itemSource);
+            $firstItem = reset($items);
+            $shareTime = (int)$firstItem['stime'];
+        }
+
+        if ($defaultExpireDateEnforced) {
+            // initialize max date with share time
+            $maxDate = new \DateTime();
+            $maxDate->setTimestamp($shareTime);
+            $maxDays = \OCP\Config::getAppValue('core', 'shareapi_expire_after_n_days', '7');
+            $maxDate->add(new \DateInterval('P' . $maxDays . 'D'));
+            if ($date > $maxDate) {
+                $warning = 'Cannot set expiration date. Shares cannot expire later than ' . $maxDays . ' after they have been shared';
+                $warning_t = $l->t('Cannot set expiration date. Shares cannot expire later than %s after they have been shared', array($maxDays));
+                \OCP\Util::writeLog('OCP\Share', $warning, \OCP\Util::WARN);
+                throw new \Exception($warning_t);
+            }
+        }
+
+        if ($date < $today) {
+            $message = 'Cannot set expiration date. Expiration date is in the past';
+            $message_t = $l->t('Cannot set expiration date. Expiration date is in the past');
+            \OCP\Util::writeLog('OCP\Share', $message, \OCP\Util::WARN);
+            throw new \Exception($message_t);
+        }
+
+        return $date;
+    }
+
+    /**
+     * Set expiration date for a share
+     * @param string $itemType
+     * @param string $itemSource
+     * @param string $date expiration date
+     * @param int $shareTime timestamp from when the file was shared
+     * @return boolean
+     * @throws \Exception when the expire date is not set, in the past or further in the future then the enforced date
+     */
+    public static function setExpirationDate($itemType, $itemSource, $date, $shareTime = null) {
+        $user = \OC_User::getUser();
+        $l = \OC::$server->getL10N('lib');
+
+        if ($date == '') {
+            if (\OCP\Util::isDefaultExpireDateEnforced()) {
+                $warning = 'Cannot clear expiration date. Shares are required to have an expiration date.';
+                $warning_t = $l->t('Cannot clear expiration date. Shares are required to have an expiration date.');
+                \OCP\Util::writeLog('OCP\Share', $warning, \OCP\Util::WARN);
+                throw new \Exception($warning_t);
+            } else {
+                $date = null;
+            }
+        } else {
+            $date = self::validateExpireDate($date, $shareTime, $itemType, $itemSource);
+        }
+        $query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `expiration` = ? WHERE `item_type` = ? AND `item_source` = ?  AND `uid_owner` = ? AND `share_type` = ?');
+        $query->bindValue(1, $date, 'datetime');
+        $query->bindValue(2, $itemType);
+        $query->bindValue(3, $itemSource);
+        $query->bindValue(4, $user);
+        $query->bindValue(5, \OCP\Share::SHARE_TYPE_LINK);
+
+        $query->execute();
+
+        \OC_Hook::emit('OCP\Share', 'post_set_expiration_date', array(
+            'itemType' => $itemType,
+            'itemSource' => $itemSource,
+            'date' => $date,
+            'uidOwner' => $user
+        ));
+
+        return true;
+    }
+
+    /**
+     * Retrieve the owner of a connection
+     *
+     * @param IDBConnection $connection
+     * @param int $shareId
+     * @throws \Exception
+     * @return string uid of share owner
+     */
+    private static function getShareOwner(IDBConnection $connection, $shareId) {
+        $qb = $connection->getQueryBuilder();
+
+        $qb->select('uid_owner')
+            ->from('share')
+            ->where($qb->expr()->eq('id', $qb->createParameter('shareId')))
+            ->setParameter(':shareId', $shareId);
+        $result = $qb->execute();
+        $result = $result->fetch();
+
+        if (empty($result)) {
+            throw new \Exception('Share not found');
+        }
+
+        return $result['uid_owner'];
+    }
+
+    /**
+     * Set password for a public link share
+     *
+     * @param IUserSession $userSession
+     * @param IDBConnection $connection
+     * @param IConfig $config
+     * @param int $shareId
+     * @param string $password
+     * @throws \Exception
+     * @return boolean
+     */
+    public static function setPassword(IUserSession $userSession,
+                                        IDBConnection $connection,
+                                        IConfig $config,
+                                        $shareId, $password) {
+        $user = $userSession->getUser();
+        if (is_null($user)) {
+            throw new \Exception("User not logged in");
+        }
+
+        $uid = self::getShareOwner($connection, $shareId);
+
+        if ($uid !== $user->getUID()) {
+            throw new \Exception('Cannot update share of a different user');
+        }
+
+        if ($password === '') {
+            $password = null;
+        }
+
+        //If passwords are enforced the password can't be null
+        if (self::enforcePassword($config) && is_null($password)) {
+            throw new \Exception('Cannot remove password');
+        }
+
+        self::verifyPassword($password);
+
+        $qb = $connection->getQueryBuilder();
+        $qb->update('share')
+            ->set('share_with', $qb->createParameter('pass'))
+            ->where($qb->expr()->eq('id', $qb->createParameter('shareId')))
+            ->setParameter(':pass', is_null($password) ? null : \OC::$server->getHasher()->hash($password))
+            ->setParameter(':shareId', $shareId);
+
+        $qb->execute();
+
+        return true;
+    }
+
+    /**
+     * Checks whether a share has expired, calls unshareItem() if yes.
+     * @param array $item Share data (usually database row)
+     * @return boolean True if item was expired, false otherwise.
+     */
+    protected static function expireItem(array $item) {
+
+        $result = false;
+
+        // only use default expiration date for link shares
+        if ((int) $item['share_type'] === self::SHARE_TYPE_LINK) {
+
+            // calculate expiration date
+            if (!empty($item['expiration'])) {
+                $userDefinedExpire = new \DateTime($item['expiration']);
+                $expires = $userDefinedExpire->getTimestamp();
+            } else {
+                $expires = null;
+            }
+
+
+            // get default expiration settings
+            $defaultSettings = Helper::getDefaultExpireSetting();
+            $expires = Helper::calculateExpireDate($defaultSettings, $item['stime'], $expires);
+
+
+            if (is_int($expires)) {
+                $now = time();
+                if ($now > $expires) {
+                    self::unshareItem($item);
+                    $result = true;
+                }
+            }
+        }
+        return $result;
+    }
+
+    /**
+     * Unshares a share given a share data array
+     * @param array $item Share data (usually database row)
+     * @param int $newParent parent ID
+     * @return null
+     */
+    protected static function unshareItem(array $item, $newParent = null) {
+
+        $shareType = (int)$item['share_type'];
+        $shareWith = null;
+        if ($shareType !== \OCP\Share::SHARE_TYPE_LINK) {
+            $shareWith = $item['share_with'];
+        }
+
+        // Pass all the vars we have for now, they may be useful
+        $hookParams = array(
+            'id'            => $item['id'],
+            'itemType'      => $item['item_type'],
+            'itemSource'    => $item['item_source'],
+            'shareType'     => $shareType,
+            'shareWith'     => $shareWith,
+            'itemParent'    => $item['parent'],
+            'uidOwner'      => $item['uid_owner'],
+        );
+        if($item['item_type'] === 'file' || $item['item_type'] === 'folder') {
+            $hookParams['fileSource'] = $item['file_source'];
+            $hookParams['fileTarget'] = $item['file_target'];
+        }
+
+        \OC_Hook::emit('OCP\Share', 'pre_unshare', $hookParams);
+        $deletedShares = Helper::delete($item['id'], false, null, $newParent);
+        $deletedShares[] = $hookParams;
+        $hookParams['deletedShares'] = $deletedShares;
+        \OC_Hook::emit('OCP\Share', 'post_unshare', $hookParams);
+        if ((int)$item['share_type'] === \OCP\Share::SHARE_TYPE_REMOTE && \OC::$server->getUserSession()->getUser()) {
+            list(, $remote) = Helper::splitUserRemote($item['share_with']);
+            self::sendRemoteUnshare($remote, $item['id'], $item['token']);
+        }
+    }
+
+    /**
+     * Get the backend class for the specified item type
+     * @param string $itemType
+     * @throws \Exception
+     * @return \OCP\Share_Backend
+     */
+    public static function getBackend($itemType) {
+        $l = \OC::$server->getL10N('lib');
+        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 \OCP\Share_Backend)) {
+                    $message = 'Sharing backend %s must implement the interface OCP\Share_Backend';
+                    $message_t = $l->t('Sharing backend %s must implement the interface OCP\Share_Backend', array($class));
+                    \OCP\Util::writeLog('OCP\Share', sprintf($message, $class), \OCP\Util::ERROR);
+                    throw new \Exception($message_t);
+                }
+                return self::$backends[$itemType];
+            } else {
+                $message = 'Sharing backend %s not found';
+                $message_t = $l->t('Sharing backend %s not found', array($class));
+                \OCP\Util::writeLog('OCP\Share', sprintf($message, $class), \OCP\Util::ERROR);
+                throw new \Exception($message_t);
+            }
+        }
+        $message = 'Sharing backend for %s not found';
+        $message_t = $l->t('Sharing backend for %s not found', array($itemType));
+        \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemType), \OCP\Util::ERROR);
+        throw new \Exception($message_t);
+    }
+
+    /**
+     * Check if resharing is allowed
+     * @return boolean true if allowed or false
+     *
+     * Resharing is allowed by default if not configured
+     */
+    public static function isResharingAllowed() {
+        if (!isset(self::$isResharingAllowed)) {
+            if (\OC::$server->getAppConfig()->getValue('core', 'shareapi_allow_resharing', 'yes') == 'yes') {
+                self::$isResharingAllowed = true;
+            } else {
+                self::$isResharingAllowed = false;
+            }
+        }
+        return self::$isResharingAllowed;
+    }
+
+    /**
+     * Get a list of collection item types for the specified item type
+     * @param string $itemType
+     * @return array
+     */
+    private static function getCollectionItemTypes($itemType) {
+        $collectionTypes = array($itemType);
+        foreach (self::$backendTypes as $type => $backend) {
+            if (in_array($backend['collectionOf'], $collectionTypes)) {
+                $collectionTypes[] = $type;
+            }
+        }
+        // TODO Add option for collections to be collection of themselves, only 'folder' does it now...
+        if (isset(self::$backendTypes[$itemType]) && (!self::getBackend($itemType) instanceof \OCP\Share_Backend_Collection || $itemType != 'folder')) {
+            unset($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;
+    }
+
+    /**
+     * Get the owners of items shared with a user.
+     *
+     * @param string $user The user the items are shared with.
+     * @param string $type The type of the items shared with the user.
+     * @param boolean $includeCollections Include collection item types (optional)
+     * @param boolean $includeOwner include owner in the list of users the item is shared with (optional)
+     * @return array
+     */
+    public static function getSharedItemsOwners($user, $type, $includeCollections = false, $includeOwner = false) {
+        // First, we find out if $type is part of a collection (and if that collection is part of
+        // another one and so on).
+        $collectionTypes = array();
+        if (!$includeCollections || !$collectionTypes = self::getCollectionItemTypes($type)) {
+            $collectionTypes[] = $type;
+        }
+
+        // Of these collection types, along with our original $type, we make a
+        // list of the ones for which a sharing backend has been registered.
+        // FIXME: Ideally, we wouldn't need to nest getItemsSharedWith in this loop but just call it
+        // with its $includeCollections parameter set to true. Unfortunately, this fails currently.
+        $allMaybeSharedItems = array();
+        foreach ($collectionTypes as $collectionType) {
+            if (isset(self::$backends[$collectionType])) {
+                $allMaybeSharedItems[$collectionType] = self::getItemsSharedWithUser(
+                    $collectionType,
+                    $user,
+                    self::FORMAT_NONE
+                );
+            }
+        }
+
+        $owners = array();
+        if ($includeOwner) {
+            $owners[] = $user;
+        }
+
+        // We take a look at all shared items of the given $type (or of the collections it is part of)
+        // and find out their owners. Then, we gather the tags for the original $type from all owners,
+        // and return them as elements of a list that look like "Tag (owner)".
+        foreach ($allMaybeSharedItems as $collectionType => $maybeSharedItems) {
+            foreach ($maybeSharedItems as $sharedItem) {
+                if (isset($sharedItem['id'])) { //workaround for https://github.com/owncloud/core/issues/2814
+                    $owners[] = $sharedItem['uid_owner'];
+                }
+            }
+        }
+
+        return $owners;
+    }
+
+    /**
+     * Get shared items from the database
+     * @param string $itemType
+     * @param string $item Item source or target (optional)
+     * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, SHARE_TYPE_LINK, $shareTypeUserAndGroups, or $shareTypeGroupUserUnique
+     * @param string $shareWith User or group the item is being shared with
+     * @param string $uidOwner User that is the owner of shared items (optional)
+     * @param int $format Format to convert items to with formatItems() (optional)
+     * @param mixed $parameters to pass to formatItems() (optional)
+     * @param int $limit Number of items to return, -1 to return all matches (optional)
+     * @param boolean $includeCollections Include collection item types (optional)
+     * @param boolean $itemShareWithBySource (optional)
+     * @param boolean $checkExpireDate
+     * @return array
+     *
+     * See public functions getItem(s)... for parameter usage
+     *
+     */
+    public static function getItems($itemType, $item = null, $shareType = null, $shareWith = null,
+                                    $uidOwner = null, $format = self::FORMAT_NONE, $parameters = null, $limit = -1,
+                                    $includeCollections = false, $itemShareWithBySource = false, $checkExpireDate  = true) {
+        if (!self::isEnabled()) {
+            return array();
+        }
+        $backend = self::getBackend($itemType);
+        $collectionTypes = false;
+        // Get filesystem root to add it to the file target and remove from the
+        // file source, match file_source with the file cache
+        if ($itemType == 'file' || $itemType == 'folder') {
+            if(!is_null($uidOwner)) {
+                $root = \OC\Files\Filesystem::getRoot();
+            } else {
+                $root = '';
+            }
+            $where = 'INNER JOIN `*PREFIX*filecache` ON `file_source` = `*PREFIX*filecache`.`fileid` ';
+            if (!isset($item)) {
+                $where .= ' AND `file_target` IS NOT NULL ';
+            }
+            $where .= 'INNER JOIN `*PREFIX*storages` ON `numeric_id` = `*PREFIX*filecache`.`storage` ';
+            $fileDependent = true;
+            $queryArgs = array();
+        } else {
+            $fileDependent = false;
+            $root = '';
+            $collectionTypes = self::getCollectionItemTypes($itemType);
+            if ($includeCollections && !isset($item) && $collectionTypes) {
+                // If includeCollections is true, find collections of this item type, e.g. a music album contains songs
+                if (!in_array($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 (\OC::$server->getAppConfig()->getValue('core', 'shareapi_allow_links', 'yes') !== 'yes') {
+            $where .= ' AND `share_type` != ?';
+            $queryArgs[] = self::SHARE_TYPE_LINK;
+        }
+        if (isset($shareType)) {
+            // Include all user and group items
+            if ($shareType == self::$shareTypeUserAndGroups && isset($shareWith)) {
+                $where .= ' AND ((`share_type` in (?, ?) AND `share_with` = ?) ';
+                $queryArgs[] = self::SHARE_TYPE_USER;
+                $queryArgs[] = self::$shareTypeGroupUserUnique;
+                $queryArgs[] = $shareWith;
+
+                $user = \OC::$server->getUserManager()->get($shareWith);
+                $groups = [];
+                if ($user) {
+                    $groups = \OC::$server->getGroupManager()->getUserGroupIds($user);
+                }
+                if (!empty($groups)) {
+                    $placeholders = join(',', array_fill(0, count($groups), '?'));
+                    $where .= ' OR (`share_type` = ? AND `share_with` IN ('.$placeholders.')) ';
+                    $queryArgs[] = self::SHARE_TYPE_GROUP;
+                    $queryArgs = array_merge($queryArgs, $groups);
+                }
+                $where .= ')';
+                // 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 ($fileDependent) {
+                $column = 'file_source';
+            } else {
+                $column = 'item_source';
+            }
+        } else {
+            if ($fileDependent) {
+                $column = 'file_target';
+            } else {
+                $column = 'item_target';
+            }
+        }
+        if (isset($item)) {
+            $collectionTypes = self::getCollectionItemTypes($itemType);
+            if ($includeCollections && $collectionTypes && !in_array('folder', $collectionTypes)) {
+                $where .= ' AND (';
+            } else {
+                $where .= ' AND';
+            }
+            // If looking for own shared items, check item_source else check item_target
+            if (isset($uidOwner) || $itemShareWithBySource) {
+                // If item type is a file, file source needs to be checked in case the item was converted
+                if ($fileDependent) {
+                    $where .= ' `file_source` = ?';
+                    $column = 'file_source';
+                } else {
+                    $where .= ' `item_source` = ?';
+                    $column = 'item_source';
+                }
+            } else {
+                if ($fileDependent) {
+                    $where .= ' `file_target` = ?';
+                    $item = \OC\Files\Filesystem::normalizePath($item);
+                } else {
+                    $where .= ' `item_target` = ?';
+                }
+            }
+            $queryArgs[] = $item;
+            if ($includeCollections && $collectionTypes && !in_array('folder', $collectionTypes)) {
+                $placeholders = join(',', array_fill(0, count($collectionTypes), '?'));
+                $where .= ' OR `item_type` IN ('.$placeholders.'))';
+                $queryArgs = array_merge($queryArgs, $collectionTypes);
+            }
+        }
+
+        if ($shareType == self::$shareTypeUserAndGroups && $limit === 1) {
+            // 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';
+        } else {
+            $where .= ' ORDER BY `*PREFIX*share`.`id` ASC';
+        }
+
+        if ($limit != -1 && !$includeCollections) {
+            // The limit must be at least 3, because filtering needs to be done
+            if ($limit < 3) {
+                $queryLimit = 3;
+            } else {
+                $queryLimit = $limit;
+            }
+        } else {
+            $queryLimit = null;
+        }
+        $select = self::createSelectStatement($format, $fileDependent, $uidOwner);
+        $root = strlen($root);
+        $query = \OC_DB::prepare('SELECT '.$select.' FROM `*PREFIX*share` '.$where, $queryLimit);
+        $result = $query->execute($queryArgs);
+        if ($result === false) {
+            \OCP\Util::writeLog('OCP\Share',
+                \OC_DB::getErrorMessage() . ', select=' . $select . ' where=',
+                \OCP\Util::ERROR);
+        }
+        $items = array();
+        $targets = array();
+        $switchedItems = array();
+        $mounts = array();
+        while ($row = $result->fetchRow()) {
+            self::transformDBResults($row);
+            // Filter out duplicate group shares for users with unique targets
+            if ($fileDependent && !self::isFileReachable($row['path'], $row['storage_id'])) {
+                continue;
+            }
+            if ($row['share_type'] == self::$shareTypeGroupUserUnique && isset($items[$row['parent']])) {
+                $row['share_type'] = self::SHARE_TYPE_GROUP;
+                $row['unique_name'] = true; // remember that we use a unique name for this user
+                $row['share_with'] = $items[$row['parent']]['share_with'];
+                // if the group share was unshared from the user we keep the permission, otherwise
+                // we take the permission from the parent because this is always the up-to-date
+                // permission for the group share
+                if ($row['permissions'] > 0) {
+                    $row['permissions'] = $items[$row['parent']]['permissions'];
+                }
+                // 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['id']])) {
+                    // Check if the same owner shared with the user twice
+                    // through a group and user share - this is allowed
+                    $id = $targets[$row['id']];
+                    if (isset($items[$id]) && $items[$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[$id]['permissions'] & \OCP\Constants::PERMISSION_SHARE
+                            && (int)$row['permissions'] & \OCP\Constants::PERMISSION_SHARE) {
+                            $items[$row['id']] = $items[$id];
+                            $switchedItems[$id] = $row['id'];
+                            unset($items[$id]);
+                            $id = $row['id'];
+                        }
+                        $items[$id]['permissions'] |= (int)$row['permissions'];
+
+                    }
+                    continue;
+                } elseif (!empty($row['parent'])) {
+                    $targets[$row['parent']] = $row['id'];
+                }
+            }
+            // Remove root from file source paths if retrieving own shared items
+            if (isset($uidOwner) && isset($row['path'])) {
+                if (isset($row['parent'])) {
+                    $query = \OC_DB::prepare('SELECT `file_target` FROM `*PREFIX*share` WHERE `id` = ?');
+                    $parentResult = $query->execute(array($row['parent']));
+                    if ($result === false) {
+                        \OCP\Util::writeLog('OCP\Share', 'Can\'t select parent: ' .
+                            \OC_DB::getErrorMessage() . ', select=' . $select . ' where=' . $where,
+                            \OCP\Util::ERROR);
+                    } else {
+                        $parentRow = $parentResult->fetchRow();
+                        $tmpPath = $parentRow['file_target'];
+                        // find the right position where the row path continues from the target path
+                        $pos = strrpos($row['path'], $parentRow['file_target']);
+                        $subPath = substr($row['path'], $pos);
+                        $splitPath = explode('/', $subPath);
+                        foreach (array_slice($splitPath, 2) as $pathPart) {
+                            $tmpPath = $tmpPath . '/' . $pathPart;
+                        }
+                        $row['path'] = $tmpPath;
+                    }
+                } else {
+                    if (!isset($mounts[$row['storage']])) {
+                        $mountPoints = \OC\Files\Filesystem::getMountByNumericId($row['storage']);
+                        if (is_array($mountPoints) && !empty($mountPoints)) {
+                            $mounts[$row['storage']] = current($mountPoints);
+                        }
+                    }
+                    if (!empty($mounts[$row['storage']])) {
+                        $path = $mounts[$row['storage']]->getMountPoint().$row['path'];
+                        $relPath = substr($path, $root); // path relative to data/user
+                        $row['path'] = rtrim($relPath, '/');
+                    }
+                }
+            }
+
+            if($checkExpireDate) {
+                if (self::expireItem($row)) {
+                    continue;
+                }
+            }
+            // Check if resharing is allowed, if not remove share permission
+            if (isset($row['permissions']) && (!self::isResharingAllowed() | \OCP\Util::isSharingDisabledForUser())) {
+                $row['permissions'] &= ~\OCP\Constants::PERMISSION_SHARE;
+            }
+            // Add display names to result
+            $row['share_with_displayname'] = $row['share_with'];
+            if ( isset($row['share_with']) && $row['share_with'] != '' &&
+                $row['share_type'] === self::SHARE_TYPE_USER) {
+                $row['share_with_displayname'] = \OCP\User::getDisplayName($row['share_with']);
+            } else if(isset($row['share_with']) && $row['share_with'] != '' &&
+                $row['share_type'] === self::SHARE_TYPE_REMOTE) {
+                $addressBookEntries = \OC::$server->getContactsManager()->search($row['share_with'], ['CLOUD']);
+                foreach ($addressBookEntries as $entry) {
+                    foreach ($entry['CLOUD'] as $cloudID) {
+                        if ($cloudID === $row['share_with']) {
+                            $row['share_with_displayname'] = $entry['FN'];
+                        }
+                    }
+                }
+            }
+            if ( isset($row['uid_owner']) && $row['uid_owner'] != '') {
+                $row['displayname_owner'] = \OCP\User::getDisplayName($row['uid_owner']);
+            }
+
+            if ($row['permissions'] > 0) {
+                $items[$row['id']] = $row;
+            }
+
+        }
+
+        // group items if we are looking for items shared with the current user
+        if (isset($shareWith) && $shareWith === \OCP\User::getUser()) {
+            $items = self::groupItems($items, $itemType);
+        }
+
+        if (!empty($items)) {
+            $collectionItems = array();
+            foreach ($items as &$row) {
+                // Return only the item instead of a 2-dimensional array
+                if ($limit == 1 && $row[$column] == $item && ($row['item_type'] == $itemType || $itemType == 'file')) {
+                    if ($format == self::FORMAT_NONE) {
+                        return $row;
+                    } else {
+                        break;
+                    }
+                }
+                // Check if this is a collection of the requested item type
+                if ($includeCollections && $collectionTypes && $row['item_type'] !== 'folder' && in_array($row['item_type'], $collectionTypes)) {
+                    if (($collectionBackend = self::getBackend($row['item_type']))
+                        && $collectionBackend instanceof \OCP\Share_Backend_Collection) {
+                        // Collections can be inside collections, check if the item is a collection
+                        if (isset($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 \OCP\Share_Backend_File_Dependent) {
+                                    if ($row['item_type'] == 'file' || $row['item_type'] == 'folder') {
+                                        $childItem['file_source'] = $child['source'];
+                                    } else { // TODO is this really needed if we already know that we use the file backend?
+                                        $meta = \OC\Files\Filesystem::getFileInfo($child['file_path']);
+                                        $childItem['file_source'] = $meta['fileid'];
+                                    }
+                                    $childItem['file_target'] =
+                                        \OC\Files\Filesystem::normalizePath($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
+                    $toRemove = $row['id'];
+                    if (array_key_exists($toRemove, $switchedItems)) {
+                        $toRemove = $switchedItems[$toRemove];
+                    }
+                    unset($items[$toRemove]);
+                } elseif ($includeCollections && $collectionTypes && in_array($row['item_type'], $collectionTypes)) {
+                    // FIXME: Thats a dirty hack to improve file sharing performance,
+                    // see github issue #10588 for more details
+                    // Need to find a solution which works for all back-ends
+                    $collectionBackend = self::getBackend($row['item_type']);
+                    $sharedParents = $collectionBackend->getParents($row['item_source']);
+                    foreach ($sharedParents as $parent) {
+                        $collectionItems[] = $parent;
+                    }
+                }
+            }
+            if (!empty($collectionItems)) {
+                $collectionItems = array_unique($collectionItems, SORT_REGULAR);
+                $items = array_merge($items, $collectionItems);
+            }
+
+            // filter out invalid items, these can appear when subshare entries exist
+            // for a group in which the requested user isn't a member any more
+            $items = array_filter($items, function($item) {
+                return $item['share_type'] !== self::$shareTypeGroupUserUnique;
+            });
+
+            return self::formatResult($items, $column, $backend, $format, $parameters);
+        } elseif ($includeCollections && $collectionTypes && in_array('folder', $collectionTypes)) {
+            // FIXME: Thats a dirty hack to improve file sharing performance,
+            // see github issue #10588 for more details
+            // Need to find a solution which works for all back-ends
+            $collectionItems = array();
+            $collectionBackend = self::getBackend('folder');
+            $sharedParents = $collectionBackend->getParents($item, $shareWith, $uidOwner);
+            foreach ($sharedParents as $parent) {
+                $collectionItems[] = $parent;
+            }
+            if ($limit === 1) {
+                return reset($collectionItems);
+            }
+            return self::formatResult($collectionItems, $column, $backend, $format, $parameters);
+        }
+
+        return array();
+    }
+
+    /**
+     * group items with link to the same source
+     *
+     * @param array $items
+     * @param string $itemType
+     * @return array of grouped items
+     */
+    protected static function groupItems($items, $itemType) {
+
+        $fileSharing = ($itemType === 'file' || $itemType === 'folder') ? true : false;
+
+        $result = array();
+
+        foreach ($items as $item) {
+            $grouped = false;
+            foreach ($result as $key => $r) {
+                // for file/folder shares we need to compare file_source, otherwise we compare item_source
+                // only group shares if they already point to the same target, otherwise the file where shared
+                // before grouping of shares was added. In this case we don't group them toi avoid confusions
+                if (( $fileSharing && $item['file_source'] === $r['file_source'] && $item['file_target'] === $r['file_target']) ||
+                    (!$fileSharing && $item['item_source'] === $r['item_source'] && $item['item_target'] === $r['item_target'])) {
+                    // add the first item to the list of grouped shares
+                    if (!isset($result[$key]['grouped'])) {
+                        $result[$key]['grouped'][] = $result[$key];
+                    }
+                    $result[$key]['permissions'] = (int) $item['permissions'] | (int) $r['permissions'];
+                    $result[$key]['grouped'][] = $item;
+                    $grouped = true;
+                    break;
+                }
+            }
+
+            if (!$grouped) {
+                $result[] = $item;
+            }
+
+        }
+
+        return $result;
+    }
+
+    /**
+     * Put shared item into the database
+     * @param string $itemType Item type
+     * @param string $itemSource Item source
+     * @param int $shareType SHARE_TYPE_USER, SHARE_TYPE_GROUP, or SHARE_TYPE_LINK
+     * @param string $shareWith User or group the item is being shared with
+     * @param string $uidOwner User that is the owner of shared item
+     * @param int $permissions CRUDS permissions
+     * @param boolean|array $parentFolder Parent folder target (optional)
+     * @param string $token (optional)
+     * @param string $itemSourceName name of the source item (optional)
+     * @param \DateTime $expirationDate (optional)
+     * @throws \Exception
+     * @return mixed id of the new share or false
+     */
+    private static function put($itemType, $itemSource, $shareType, $shareWith, $uidOwner,
+                                $permissions, $parentFolder = null, $token = null, $itemSourceName = null, \DateTime $expirationDate = null) {
+
+        $queriesToExecute = array();
+        $suggestedItemTarget = null;
+        $groupFileTarget = $fileTarget = $suggestedFileTarget = $filePath = '';
+        $groupItemTarget = $itemTarget = $fileSource = $parent = 0;
+
+        $result = self::checkReshare($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, $itemSourceName, $expirationDate);
+        if(!empty($result)) {
+            $parent = $result['parent'];
+            $itemSource = $result['itemSource'];
+            $fileSource = $result['fileSource'];
+            $suggestedItemTarget = $result['suggestedItemTarget'];
+            $suggestedFileTarget = $result['suggestedFileTarget'];
+            $filePath = $result['filePath'];
+        }
+
+        $isGroupShare = false;
+        if ($shareType == self::SHARE_TYPE_GROUP) {
+            $isGroupShare = true;
+            if (isset($shareWith['users'])) {
+                $users = $shareWith['users'];
+            } else {
+                $group = \OC::$server->getGroupManager()->get($shareWith['group']);
+                if ($group) {
+                    $users = $group->searchUsers('', -1, 0);
+                    $userIds = [];
+                    foreach ($users as $user) {
+                        $userIds[] = $user->getUID();
+                    }
+                    $users = $userIds;
+                } else {
+                    $users = [];
+                }
+            }
+            // remove current user from list
+            if (in_array(\OCP\User::getUser(), $users)) {
+                unset($users[array_search(\OCP\User::getUser(), $users)]);
+            }
+            $groupItemTarget = Helper::generateTarget($itemType, $itemSource,
+                $shareType, $shareWith['group'], $uidOwner, $suggestedItemTarget);
+            $groupFileTarget = Helper::generateTarget($itemType, $itemSource,
+                $shareType, $shareWith['group'], $uidOwner, $filePath);
+
+            // add group share to table and remember the id as parent
+            $queriesToExecute['groupShare'] = array(
+                'itemType'			=> $itemType,
+                'itemSource'		=> $itemSource,
+                'itemTarget'		=> $groupItemTarget,
+                'shareType'			=> $shareType,
+                'shareWith'			=> $shareWith['group'],
+                'uidOwner'			=> $uidOwner,
+                'permissions'		=> $permissions,
+                'shareTime'			=> time(),
+                'fileSource'		=> $fileSource,
+                'fileTarget'		=> $groupFileTarget,
+                'token'				=> $token,
+                'parent'			=> $parent,
+                'expiration'		=> $expirationDate,
+            );
+
+        } else {
+            $users = array($shareWith);
+            $itemTarget = Helper::generateTarget($itemType, $itemSource, $shareType, $shareWith, $uidOwner,
+                $suggestedItemTarget);
+        }
+
+        $run = true;
+        $error = '';
+        $preHookData = array(
+            'itemType' => $itemType,
+            'itemSource' => $itemSource,
+            'shareType' => $shareType,
+            'uidOwner' => $uidOwner,
+            'permissions' => $permissions,
+            'fileSource' => $fileSource,
+            'expiration' => $expirationDate,
+            'token' => $token,
+            'run' => &$run,
+            'error' => &$error
+        );
+
+        $preHookData['itemTarget'] = ($isGroupShare) ? $groupItemTarget : $itemTarget;
+        $preHookData['shareWith'] = ($isGroupShare) ? $shareWith['group'] : $shareWith;
+
+        \OC_Hook::emit('OCP\Share', 'pre_shared', $preHookData);
+
+        if ($run === false) {
+            throw new \Exception($error);
+        }
+
+        foreach ($users as $user) {
+            $sourceId = ($itemType === 'file' || $itemType === 'folder') ? $fileSource : $itemSource;
+            $sourceExists = self::getItemSharedWithBySource($itemType, $sourceId, self::FORMAT_NONE, null, true, $user);
+
+            $userShareType = ($isGroupShare) ? self::$shareTypeGroupUserUnique : $shareType;
+
+            if ($sourceExists && $sourceExists['item_source'] === $itemSource) {
+                $fileTarget = $sourceExists['file_target'];
+                $itemTarget = $sourceExists['item_target'];
+
+                // for group shares we don't need a additional entry if the target is the same
+                if($isGroupShare && $groupItemTarget === $itemTarget) {
+                    continue;
+                }
+
+            } elseif(!$sourceExists && !$isGroupShare)  {
+
+                $itemTarget = Helper::generateTarget($itemType, $itemSource, $userShareType, $user,
+                    $uidOwner, $suggestedItemTarget, $parent);
+                if (isset($fileSource)) {
+                    if ($parentFolder) {
+                        if ($parentFolder === true) {
+                            $fileTarget = Helper::generateTarget('file', $filePath, $userShareType, $user,
+                                $uidOwner, $suggestedFileTarget, $parent);
+                            if ($fileTarget != $groupFileTarget) {
+                                $parentFolders[$user]['folder'] = $fileTarget;
+                            }
+                        } else if (isset($parentFolder[$user])) {
+                            $fileTarget = $parentFolder[$user]['folder'].$itemSource;
+                            $parent = $parentFolder[$user]['id'];
+                        }
+                    } else {
+                        $fileTarget = Helper::generateTarget('file', $filePath, $userShareType,
+                            $user, $uidOwner, $suggestedFileTarget, $parent);
+                    }
+                } else {
+                    $fileTarget = null;
+                }
+
+            } else {
+
+                // group share which doesn't exists until now, check if we need a unique target for this user
+
+                $itemTarget = Helper::generateTarget($itemType, $itemSource, self::SHARE_TYPE_USER, $user,
+                    $uidOwner, $suggestedItemTarget, $parent);
+
+                // do we also need a file target
+                if (isset($fileSource)) {
+                    $fileTarget = Helper::generateTarget('file', $filePath, self::SHARE_TYPE_USER, $user,
+                        $uidOwner, $suggestedFileTarget, $parent);
+                } else {
+                    $fileTarget = null;
+                }
+
+                if (($itemTarget === $groupItemTarget) &&
+                    (!isset($fileSource) || $fileTarget === $groupFileTarget)) {
+                    continue;
+                }
+            }
+
+            $queriesToExecute[] = array(
+                'itemType'			=> $itemType,
+                'itemSource'		=> $itemSource,
+                'itemTarget'		=> $itemTarget,
+                'shareType'			=> $userShareType,
+                'shareWith'			=> $user,
+                'uidOwner'			=> $uidOwner,
+                'permissions'		=> $permissions,
+                'shareTime'			=> time(),
+                'fileSource'		=> $fileSource,
+                'fileTarget'		=> $fileTarget,
+                'token'				=> $token,
+                'parent'			=> $parent,
+                'expiration'		=> $expirationDate,
+            );
+
+        }
+
+        $id = false;
+        if ($isGroupShare) {
+            $id = self::insertShare($queriesToExecute['groupShare']);
+            // Save this id, any extra rows for this group share will need to reference it
+            $parent = \OC::$server->getDatabaseConnection()->lastInsertId('*PREFIX*share');
+            unset($queriesToExecute['groupShare']);
+        }
+
+        foreach ($queriesToExecute as $shareQuery) {
+            $shareQuery['parent'] = $parent;
+            $id = self::insertShare($shareQuery);
+        }
+
+        $postHookData = array(
+            'itemType' => $itemType,
+            'itemSource' => $itemSource,
+            'parent' => $parent,
+            'shareType' => $shareType,
+            'uidOwner' => $uidOwner,
+            'permissions' => $permissions,
+            'fileSource' => $fileSource,
+            'id' => $parent,
+            'token' => $token,
+            'expirationDate' => $expirationDate,
+        );
+
+        $postHookData['shareWith'] = ($isGroupShare) ? $shareWith['group'] : $shareWith;
+        $postHookData['itemTarget'] = ($isGroupShare) ? $groupItemTarget : $itemTarget;
+        $postHookData['fileTarget'] = ($isGroupShare) ? $groupFileTarget : $fileTarget;
+
+        \OC_Hook::emit('OCP\Share', 'post_shared', $postHookData);
+
+
+        return $id ? $id : false;
+    }
+
+    /**
+     * @param string $itemType
+     * @param string $itemSource
+     * @param int $shareType
+     * @param string $shareWith
+     * @param string $uidOwner
+     * @param int $permissions
+     * @param string|null $itemSourceName
+     * @param null|\DateTime $expirationDate
+     */
+    private static function checkReshare($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, $itemSourceName, $expirationDate) {
+        $backend = self::getBackend($itemType);
+
+        $l = \OC::$server->getL10N('lib');
+        $result = array();
+
+        $column = ($itemType === 'file' || $itemType === 'folder') ? 'file_source' : 'item_source';
+
+        $checkReshare = self::getItemSharedWithBySource($itemType, $itemSource, self::FORMAT_NONE, null, true);
+        if ($checkReshare) {
+            // Check if attempting to share back to owner
+            if ($checkReshare['uid_owner'] == $shareWith && $shareType == self::SHARE_TYPE_USER) {
+                $message = 'Sharing %s failed, because the user %s is the original sharer';
+                $message_t = $l->t('Sharing failed, because the user %s is the original sharer', [$shareWith]);
+
+                \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OCP\Util::DEBUG);
+                throw new \Exception($message_t);
+            }
+        }
+
+        if ($checkReshare && $checkReshare['uid_owner'] !== \OC_User::getUser()) {
+            // Check if share permissions is granted
+            if (self::isResharingAllowed() && (int)$checkReshare['permissions'] & \OCP\Constants::PERMISSION_SHARE) {
+                if (~(int)$checkReshare['permissions'] & $permissions) {
+                    $message = 'Sharing %s failed, because the permissions exceed permissions granted to %s';
+                    $message_t = $l->t('Sharing %s failed, because the permissions exceed permissions granted to %s', array($itemSourceName, $uidOwner));
+
+                    \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName, $uidOwner), \OCP\Util::DEBUG);
+                    throw new \Exception($message_t);
+                } else {
+                    // TODO Don't check if inside folder
+                    $result['parent'] = $checkReshare['id'];
+
+                    $result['expirationDate'] = $expirationDate;
+                    // $checkReshare['expiration'] could be null and then is always less than any value
+                    if(isset($checkReshare['expiration']) && $checkReshare['expiration'] < $expirationDate) {
+                        $result['expirationDate'] = $checkReshare['expiration'];
+                    }
+
+                    // only suggest the same name as new target if it is a reshare of the
+                    // same file/folder and not the reshare of a child
+                    if ($checkReshare[$column] === $itemSource) {
+                        $result['filePath'] = $checkReshare['file_target'];
+                        $result['itemSource'] = $checkReshare['item_source'];
+                        $result['fileSource'] = $checkReshare['file_source'];
+                        $result['suggestedItemTarget'] = $checkReshare['item_target'];
+                        $result['suggestedFileTarget'] = $checkReshare['file_target'];
+                    } else {
+                        $result['filePath'] = ($backend instanceof \OCP\Share_Backend_File_Dependent) ? $backend->getFilePath($itemSource, $uidOwner) : null;
+                        $result['suggestedItemTarget'] = null;
+                        $result['suggestedFileTarget'] = null;
+                        $result['itemSource'] = $itemSource;
+                        $result['fileSource'] = ($backend instanceof \OCP\Share_Backend_File_Dependent) ? $itemSource : null;
+                    }
+                }
+            } else {
+                $message = 'Sharing %s failed, because resharing is not allowed';
+                $message_t = $l->t('Sharing %s failed, because resharing is not allowed', array($itemSourceName));
+
+                \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSourceName), \OCP\Util::DEBUG);
+                throw new \Exception($message_t);
+            }
+        } else {
+            $result['parent'] = null;
+            $result['suggestedItemTarget'] = null;
+            $result['suggestedFileTarget'] = null;
+            $result['itemSource'] = $itemSource;
+            $result['expirationDate'] = $expirationDate;
+            if (!$backend->isValidSource($itemSource, $uidOwner)) {
+                $message = 'Sharing %s failed, because the sharing backend for '
+                    .'%s could not find its source';
+                $message_t = $l->t('Sharing %s failed, because the sharing backend for %s could not find its source', array($itemSource, $itemType));
+                \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSource, $itemType), \OCP\Util::DEBUG);
+                throw new \Exception($message_t);
+            }
+            if ($backend instanceof \OCP\Share_Backend_File_Dependent) {
+                $result['filePath'] = $backend->getFilePath($itemSource, $uidOwner);
+                if ($itemType == 'file' || $itemType == 'folder') {
+                    $result['fileSource'] = $itemSource;
+                } else {
+                    $meta = \OC\Files\Filesystem::getFileInfo($result['filePath']);
+                    $result['fileSource'] = $meta['fileid'];
+                }
+                if ($result['fileSource'] == -1) {
+                    $message = 'Sharing %s failed, because the file could not be found in the file cache';
+                    $message_t = $l->t('Sharing %s failed, because the file could not be found in the file cache', array($itemSource));
+
+                    \OCP\Util::writeLog('OCP\Share', sprintf($message, $itemSource), \OCP\Util::DEBUG);
+                    throw new \Exception($message_t);
+                }
+            } else {
+                $result['filePath'] = null;
+                $result['fileSource'] = null;
+            }
+        }
+
+        return $result;
+    }
+
+    /**
+     *
+     * @param array $shareData
+     * @return mixed false in case of a failure or the id of the new share
+     */
+    private static function insertShare(array $shareData) {
+
+        $query = \OC_DB::prepare('INSERT INTO `*PREFIX*share` ('
+            .' `item_type`, `item_source`, `item_target`, `share_type`,'
+            .' `share_with`, `uid_owner`, `permissions`, `stime`, `file_source`,'
+            .' `file_target`, `token`, `parent`, `expiration`) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?)');
+        $query->bindValue(1, $shareData['itemType']);
+        $query->bindValue(2, $shareData['itemSource']);
+        $query->bindValue(3, $shareData['itemTarget']);
+        $query->bindValue(4, $shareData['shareType']);
+        $query->bindValue(5, $shareData['shareWith']);
+        $query->bindValue(6, $shareData['uidOwner']);
+        $query->bindValue(7, $shareData['permissions']);
+        $query->bindValue(8, $shareData['shareTime']);
+        $query->bindValue(9, $shareData['fileSource']);
+        $query->bindValue(10, $shareData['fileTarget']);
+        $query->bindValue(11, $shareData['token']);
+        $query->bindValue(12, $shareData['parent']);
+        $query->bindValue(13, $shareData['expiration'], 'datetime');
+        $result = $query->execute();
+
+        $id = false;
+        if ($result) {
+            $id =  \OC::$server->getDatabaseConnection()->lastInsertId('*PREFIX*share');
+        }
+
+        return $id;
+
+    }
+
+    /**
+     * Delete all shares with type SHARE_TYPE_LINK
+     */
+    public static function removeAllLinkShares() {
+        // Delete any link shares
+        $query = \OC_DB::prepare('SELECT `id` FROM `*PREFIX*share` WHERE `share_type` = ?');
+        $result = $query->execute(array(self::SHARE_TYPE_LINK));
+        while ($item = $result->fetchRow()) {
+            Helper::delete($item['id']);
+        }
+    }
+
+    /**
+     * In case a password protected link is not yet authenticated this function will return false
+     *
+     * @param array $linkItem
+     * @return boolean
+     */
+    public static function checkPasswordProtectedShare(array $linkItem) {
+        if (!isset($linkItem['share_with'])) {
+            return true;
+        }
+        if (!isset($linkItem['share_type'])) {
+            return true;
+        }
+        if (!isset($linkItem['id'])) {
+            return true;
+        }
+
+        if ($linkItem['share_type'] != \OCP\Share::SHARE_TYPE_LINK) {
+            return true;
+        }
+
+        if ( \OC::$server->getSession()->exists('public_link_authenticated')
+            && \OC::$server->getSession()->get('public_link_authenticated') === (string)$linkItem['id'] ) {
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * construct select statement
+     * @param int $format
+     * @param boolean $fileDependent ist it a file/folder share or a generla share
+     * @param string $uidOwner
+     * @return string select statement
+     */
+    private static function createSelectStatement($format, $fileDependent, $uidOwner = null) {
+        $select = '*';
+        if ($format == self::FORMAT_STATUSES) {
+            if ($fileDependent) {
+                $select = '`*PREFIX*share`.`id`, `*PREFIX*share`.`parent`, `share_type`, `path`, `storage`, '
+                    . '`share_with`, `uid_owner` , `file_source`, `stime`, `*PREFIX*share`.`permissions`, '
+                    . '`*PREFIX*storages`.`id` AS `storage_id`, `*PREFIX*filecache`.`parent` as `file_parent`, '
+                    . '`uid_initiator`';
+            } else {
+                $select = '`id`, `parent`, `share_type`, `share_with`, `uid_owner`, `item_source`, `stime`, `*PREFIX*share`.`permissions`';
+            }
+        } else {
+            if (isset($uidOwner)) {
+                if ($fileDependent) {
+                    $select = '`*PREFIX*share`.`id`, `item_type`, `item_source`, `*PREFIX*share`.`parent`,'
+                        . ' `share_type`, `share_with`, `file_source`, `file_target`, `path`, `*PREFIX*share`.`permissions`, `stime`,'
+                        . ' `expiration`, `token`, `storage`, `mail_send`, `uid_owner`, '
+                        . '`*PREFIX*storages`.`id` AS `storage_id`, `*PREFIX*filecache`.`parent` as `file_parent`';
+                } else {
+                    $select = '`id`, `item_type`, `item_source`, `parent`, `share_type`, `share_with`, `*PREFIX*share`.`permissions`,'
+                        . ' `stime`, `file_source`, `expiration`, `token`, `mail_send`, `uid_owner`';
+                }
+            } else {
+                if ($fileDependent) {
+                    if ($format == \OCA\Files_Sharing\ShareBackend\File::FORMAT_GET_FOLDER_CONTENTS || $format == \OCA\Files_Sharing\ShareBackend\File::FORMAT_FILE_APP_ROOT) {
+                        $select = '`*PREFIX*share`.`id`, `item_type`, `item_source`, `*PREFIX*share`.`parent`, `uid_owner`, '
+                            . '`share_type`, `share_with`, `file_source`, `path`, `file_target`, `stime`, '
+                            . '`*PREFIX*share`.`permissions`, `expiration`, `storage`, `*PREFIX*filecache`.`parent` as `file_parent`, '
+                            . '`name`, `mtime`, `mimetype`, `mimepart`, `size`, `encrypted`, `etag`, `mail_send`';
+                    } 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`, `*PREFIX*share`.`permissions`,'
+                            . '`stime`, `expiration`, `token`, `storage`, `mail_send`,'
+                            . '`*PREFIX*storages`.`id` AS `storage_id`, `*PREFIX*filecache`.`parent` as `file_parent`';
+                    }
+                }
+            }
+        }
+        return $select;
+    }
+
+
+    /**
+     * transform db results
+     * @param array $row result
+     */
+    private static function transformDBResults(&$row) {
+        if (isset($row['id'])) {
+            $row['id'] = (int) $row['id'];
+        }
+        if (isset($row['share_type'])) {
+            $row['share_type'] = (int) $row['share_type'];
+        }
+        if (isset($row['parent'])) {
+            $row['parent'] = (int) $row['parent'];
+        }
+        if (isset($row['file_parent'])) {
+            $row['file_parent'] = (int) $row['file_parent'];
+        }
+        if (isset($row['file_source'])) {
+            $row['file_source'] = (int) $row['file_source'];
+        }
+        if (isset($row['permissions'])) {
+            $row['permissions'] = (int) $row['permissions'];
+        }
+        if (isset($row['storage'])) {
+            $row['storage'] = (int) $row['storage'];
+        }
+        if (isset($row['stime'])) {
+            $row['stime'] = (int) $row['stime'];
+        }
+        if (isset($row['expiration']) && $row['share_type'] !== self::SHARE_TYPE_LINK) {
+            // discard expiration date for non-link shares, which might have been
+            // set by ancient bugs
+            $row['expiration'] = null;
+        }
+    }
+
+    /**
+     * format result
+     * @param array $items result
+     * @param string $column is it a file share or a general share ('file_target' or 'item_target')
+     * @param \OCP\Share_Backend $backend sharing backend
+     * @param int $format
+     * @param array $parameters additional format parameters
+     * @return array format result
+     */
+    private static function formatResult($items, $column, $backend, $format = self::FORMAT_NONE , $parameters = null) {
+        if ($format === self::FORMAT_NONE) {
+            return $items;
+        } else if ($format === self::FORMAT_STATUSES) {
+            $statuses = array();
+            foreach ($items as $item) {
+                if ($item['share_type'] === self::SHARE_TYPE_LINK) {
+                    if ($item['uid_initiator'] !== \OC::$server->getUserSession()->getUser()->getUID()) {
+                        continue;
+                    }
+                    $statuses[$item[$column]]['link'] = true;
+                } else if (!isset($statuses[$item[$column]])) {
+                    $statuses[$item[$column]]['link'] = false;
+                }
+                if (!empty($item['file_target'])) {
+                    $statuses[$item[$column]]['path'] = $item['path'];
+                }
+            }
+            return $statuses;
+        } else {
+            return $backend->formatItems($items, $format, $parameters);
+        }
+    }
+
+    /**
+     * remove protocol from URL
+     *
+     * @param string $url
+     * @return string
+     */
+    public static function removeProtocolFromUrl($url) {
+        if (strpos($url, 'https://') === 0) {
+            return substr($url, strlen('https://'));
+        } else if (strpos($url, 'http://') === 0) {
+            return substr($url, strlen('http://'));
+        }
+
+        return $url;
+    }
+
+    /**
+     * try http post first with https and then with http as a fallback
+     *
+     * @param string $remoteDomain
+     * @param string $urlSuffix
+     * @param array $fields post parameters
+     * @return array
+     */
+    private static function tryHttpPostToShareEndpoint($remoteDomain, $urlSuffix, array $fields) {
+        $protocol = 'https://';
+        $result = [
+            'success' => false,
+            'result' => '',
+        ];
+        $try = 0;
+        $discoveryService = \OC::$server->query(\OCP\OCS\IDiscoveryService::class);
+        while ($result['success'] === false && $try < 2) {
+            $federationEndpoints = $discoveryService->discover($protocol . $remoteDomain, 'FEDERATED_SHARING');
+            $endpoint = isset($federationEndpoints['share']) ? $federationEndpoints['share'] : '/ocs/v2.php/cloud/shares';
+            $result = \OC::$server->getHTTPHelper()->post($protocol . $remoteDomain . $endpoint . $urlSuffix . '?format=' . self::RESPONSE_FORMAT, $fields);
+            $try++;
+            $protocol = 'http://';
+        }
+
+        return $result;
+    }
+
+    /**
+     * send server-to-server share to remote server
+     *
+     * @param string $token
+     * @param string $shareWith
+     * @param string $name
+     * @param int $remote_id
+     * @param string $owner
+     * @return bool
+     */
+    private static function sendRemoteShare($token, $shareWith, $name, $remote_id, $owner) {
+
+        list($user, $remote) = Helper::splitUserRemote($shareWith);
+
+        if ($user && $remote) {
+            $url = $remote;
+
+            $local = \OC::$server->getURLGenerator()->getAbsoluteURL('/');
+
+            $fields = array(
+                'shareWith' => $user,
+                'token' => $token,
+                'name' => $name,
+                'remoteId' => $remote_id,
+                'owner' => $owner,
+                'remote' => $local,
+            );
+
+            $url = self::removeProtocolFromUrl($url);
+            $result = self::tryHttpPostToShareEndpoint($url, '', $fields);
+            $status = json_decode($result['result'], true);
+
+            if ($result['success'] && ($status['ocs']['meta']['statuscode'] === 100 || $status['ocs']['meta']['statuscode'] === 200)) {
+                \OC_Hook::emit('OCP\Share', 'federated_share_added', ['server' => $remote]);
+                return true;
+            }
+
+        }
+
+        return false;
+    }
+
+    /**
+     * send server-to-server unshare to remote server
+     *
+     * @param string $remote url
+     * @param int $id share id
+     * @param string $token
+     * @return bool
+     */
+    private static function sendRemoteUnshare($remote, $id, $token) {
+        $url = rtrim($remote, '/');
+        $fields = array('token' => $token, 'format' => 'json');
+        $url = self::removeProtocolFromUrl($url);
+        $result = self::tryHttpPostToShareEndpoint($url, '/'.$id.'/unshare', $fields);
+        $status = json_decode($result['result'], true);
+
+        return ($result['success'] && ($status['ocs']['meta']['statuscode'] === 100 || $status['ocs']['meta']['statuscode'] === 200));
+    }
+
+    /**
+     * check if user can only share with group members
+     * @return bool
+     */
+    public static function shareWithGroupMembersOnly() {
+        $value = \OC::$server->getAppConfig()->getValue('core', 'shareapi_only_share_with_group_members', 'no');
+        return ($value === 'yes') ? true : false;
+    }
+
+    /**
+     * @return bool
+     */
+    public static function isDefaultExpireDateEnabled() {
+        $defaultExpireDateEnabled = \OCP\Config::getAppValue('core', 'shareapi_default_expire_date', 'no');
+        return ($defaultExpireDateEnabled === "yes") ? true : false;
+    }
+
+    /**
+     * @return bool
+     */
+    public static function enforceDefaultExpireDate() {
+        $enforceDefaultExpireDate = \OCP\Config::getAppValue('core', 'shareapi_enforce_expire_date', 'no');
+        return ($enforceDefaultExpireDate === "yes") ? true : false;
+    }
+
+    /**
+     * @return int
+     */
+    public static function getExpireInterval() {
+        return (int)\OCP\Config::getAppValue('core', 'shareapi_expire_after_n_days', '7');
+    }
+
+    /**
+     * Checks whether the given path is reachable for the given owner
+     *
+     * @param string $path path relative to files
+     * @param string $ownerStorageId storage id of the owner
+     *
+     * @return boolean true if file is reachable, false otherwise
+     */
+    private static function isFileReachable($path, $ownerStorageId) {
+        // if outside the home storage, file is always considered reachable
+        if (!(substr($ownerStorageId, 0, 6) === 'home::' ||
+            substr($ownerStorageId, 0, 13) === 'object::user:'
+        )) {
+            return true;
+        }
+
+        // if inside the home storage, the file has to be under "/files/"
+        $path = ltrim($path, '/');
+        if (substr($path, 0, 6) === 'files/') {
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * @param IConfig $config
+     * @return bool
+     */
+    public static function enforcePassword(IConfig $config) {
+        $enforcePassword = $config->getAppValue('core', 'shareapi_enforce_links_password', 'no');
+        return ($enforcePassword === "yes") ? true : false;
+    }
+
+    /**
+     * Get all share entries, including non-unique group items
+     *
+     * @param string $owner
+     * @return array
+     */
+    public static function getAllSharesForOwner($owner) {
+        $query = 'SELECT * FROM `*PREFIX*share` WHERE `uid_owner` = ?';
+        $result = \OC::$server->getDatabaseConnection()->executeQuery($query, [$owner]);
+        return $result->fetchAll();
+    }
+
+    /**
+     * Get all share entries, including non-unique group items for a file
+     *
+     * @param int $id
+     * @return array
+     */
+    public static function getAllSharesForFileId($id) {
+        $query = 'SELECT * FROM `*PREFIX*share` WHERE `file_source` = ?';
+        $result = \OC::$server->getDatabaseConnection()->executeQuery($query, [$id]);
+        return $result->fetchAll();
+    }
+
+    /**
+     * @param string $password
+     * @throws \Exception
+     */
+    private static function verifyPassword($password) {
+
+        $accepted = true;
+        $message = '';
+        \OCP\Util::emitHook('\OC\Share', 'verifyPassword', [
+            'password' => $password,
+            'accepted' => &$accepted,
+            'message' => &$message
+        ]);
+
+        if (!$accepted) {
+            throw new \Exception($message);
+        }
+    }
 }

apps/sharebymail/lib/ShareByMailProvider.php

Spacing +25 added lines, -25 removed lines

@@ -209,10 +209,10 @@ 
 		}
 
 		$passwordPolicy = $this->getPasswordPolicy();
-		$passwordCharset = ISecureRandom::CHAR_LOWER . ISecureRandom::CHAR_UPPER . ISecureRandom::CHAR_DIGITS;
+		$passwordCharset = ISecureRandom::CHAR_LOWER.ISecureRandom::CHAR_UPPER.ISecureRandom::CHAR_DIGITS;
 		$passwordLength = 8;
 		if (!empty($passwordPolicy)) {
-			$passwordLength = (int)$passwordPolicy['minLength'] > 0 ? (int)$passwordPolicy['minLength'] : $passwordLength;
+			$passwordLength = (int) $passwordPolicy['minLength'] > 0 ? (int) $passwordPolicy['minLength'] : $passwordLength;
 			$passwordCharset .= $passwordPolicy['enforceSpecialCharacters'] ? ISecureRandom::CHAR_SYMBOLS : '';
 		}
 
@@ -349,11 +349,11 @@ 
 				$share->getSharedWith()
 			);
 		} catch (HintException $hintException) {
-			$this->logger->error('Failed to send share by mail: ' . $hintException->getMessage());
+			$this->logger->error('Failed to send share by mail: '.$hintException->getMessage());
 			$this->removeShareFromTable($shareId);
 			throw $hintException;
 		} catch (\Exception $e) {
-			$this->logger->error('Failed to send share by email: ' . $e->getMessage());
+			$this->logger->error('Failed to send share by email: '.$e->getMessage());
 			$this->removeShareFromTable($shareId);
 			throw new HintException('Failed to send share by mail',
 				$this->l->t('Failed to send share by email'));
@@ -376,7 +376,7 @@ 
 											$shareWith) {
 		$initiatorUser = $this->userManager->get($initiator);
 		$initiatorDisplayName = ($initiatorUser instanceof IUser) ? $initiatorUser->getDisplayName() : $initiator;
-		$subject = (string)$this->l->t('%s shared »%s« with you', array($initiatorDisplayName, $filename));
+		$subject = (string) $this->l->t('%s shared »%s« with you', array($initiatorDisplayName, $filename));
 
 		$message = $this->mailer->createMessage();
 
@@ -387,7 +387,7 @@ 
 		$text = $this->l->t('%s shared »%s« with you.', [$initiatorDisplayName, $filename]);
 
 		$emailTemplate->addBodyText(
-			$text . ' ' . $this->l->t('Click the button below to open it.'),
+			$text.' '.$this->l->t('Click the button below to open it.'),
 			$text
 		);
 		$emailTemplate->addBodyButton(
@@ -411,9 +411,9 @@ 
 		// The "Reply-To" is set to the sharer if an mail address is configured
 		// also the default footer contains a "Do not reply" which needs to be adjusted.
 		$initiatorEmail = $initiatorUser->getEMailAddress();
-		if($initiatorEmail !== null) {
+		if ($initiatorEmail !== null) {
 			$message->setReplyTo([$initiatorEmail => $initiatorDisplayName]);
-			$emailTemplate->addFooter($instanceName . ' - ' . $this->defaults->getSlogan());
+			$emailTemplate->addFooter($instanceName.' - '.$this->defaults->getSlogan());
 		} else {
 			$emailTemplate->addFooter();
 		}
@@ -445,7 +445,7 @@ 
 		$initiatorDisplayName = ($initiatorUser instanceof IUser) ? $initiatorUser->getDisplayName() : $initiator;
 		$initiatorEmailAddress = ($initiatorUser instanceof IUser) ? $initiatorUser->getEMailAddress() : null;
 
-		$subject = (string)$this->l->t('Password to access »%s« shared to you by %s', [$filename, $initiatorDisplayName]);
+		$subject = (string) $this->l->t('Password to access »%s« shared to you by %s', [$filename, $initiatorDisplayName]);
 		$plainBodyPart = $this->l->t("%s shared »%s« with you.\nYou should have already received a separate mail with a link to access it.\n", [$initiatorDisplayName, $filename]);
 		$htmlBodyPart = $this->l->t('%s shared »%s« with you. You should have already received a separate mail with a link to access it.', [$initiatorDisplayName, $filename]);
 
@@ -469,7 +469,7 @@ 
 		$message->setFrom([\OCP\Util::getDefaultEmailAddress($instanceName) => $senderName]);
 		if ($initiatorEmailAddress !== null) {
 			$message->setReplyTo([$initiatorEmailAddress => $initiatorDisplayName]);
-			$emailTemplate->addFooter($instanceName . ' - ' . $this->defaults->getSlogan());
+			$emailTemplate->addFooter($instanceName.' - '.$this->defaults->getSlogan());
 		} else {
 			$emailTemplate->addFooter();
 		}
@@ -508,7 +508,7 @@ 
 			);
 		}
 
-		$subject = (string)$this->l->t('Password to access »%s« shared with %s', [$filename, $shareWith]);
+		$subject = (string) $this->l->t('Password to access »%s« shared with %s', [$filename, $shareWith]);
 		$bodyPart = $this->l->t("You just shared »%s« with %s. The share was already send to the recipient. Due to the security policies defined by the administrator of %s each share needs to be protected by password and it is not allowed to send the password directly to the recipient. Therefore you need to forward the password manually to the recipient.", [$filename, $shareWith, $this->defaults->getName()]);
 
 		$message = $this->mailer->createMessage();
@@ -562,7 +562,7 @@ 
 			->orderBy('id');
 
 		$cursor = $qb->execute();
-		while($data = $cursor->fetch()) {
+		while ($data = $cursor->fetch()) {
 			$children[] = $this->createShareObject($data);
 		}
 		$cursor->closeCursor();
@@ -606,7 +606,7 @@ 
 		$qb->execute();
 		$id = $qb->getLastInsertId();
 
-		return (int)$id;
+		return (int) $id;
 	}
 
 	/**
@@ -623,7 +623,7 @@ 
 		// a real password was given
 		$validPassword = $plainTextPassword !== null && $plainTextPassword !== '';
 
-		if($validPassword && $originalShare->getPassword() !== $share->getPassword()) {
+		if ($validPassword && $originalShare->getPassword() !== $share->getPassword()) {
 			$this->sendPassword($share, $plainTextPassword);
 		}
 		/*
@@ -717,7 +717,7 @@ 
 
 		$cursor = $qb->execute();
 		$shares = [];
-		while($data = $cursor->fetch()) {
+		while ($data = $cursor->fetch()) {
 			$shares[] = $this->createShareObject($data);
 		}
 		$cursor->closeCursor();
@@ -769,7 +769,7 @@ 
 			->execute();
 
 		$shares = [];
-		while($data = $cursor->fetch()) {
+		while ($data = $cursor->fetch()) {
 			$shares[] = $this->createShareObject($data);
 		}
 		$cursor->closeCursor();
@@ -808,7 +808,7 @@ 
 
 		$cursor = $qb->execute();
 
-		while($data = $cursor->fetch()) {
+		while ($data = $cursor->fetch()) {
 			$shares[] = $this->createShareObject($data);
 		}
 		$cursor->closeCursor();
@@ -871,15 +871,15 @@ 
 	protected function createShareObject($data) {
 
 		$share = new Share($this->rootFolder, $this->userManager);
-		$share->setId((int)$data['id'])
-			->setShareType((int)$data['share_type'])
-			->setPermissions((int)$data['permissions'])
+		$share->setId((int) $data['id'])
+			->setShareType((int) $data['share_type'])
+			->setPermissions((int) $data['permissions'])
 			->setTarget($data['file_target'])
-			->setMailSend((bool)$data['mail_send'])
+			->setMailSend((bool) $data['mail_send'])
 			->setToken($data['token']);
 
 		$shareTime = new \DateTime();
-		$shareTime->setTimestamp((int)$data['stime']);
+		$shareTime->setTimestamp((int) $data['stime']);
 		$share->setShareTime($shareTime);
 		$share->setSharedWith($data['share_with']);
 		$share->setPassword($data['password']);
@@ -890,7 +890,7 @@ 
 		} else {
 			//OLD SHARE
 			$share->setSharedBy($data['uid_owner']);
-			$path = $this->getNode($share->getSharedBy(), (int)$data['file_source']);
+			$path = $this->getNode($share->getSharedBy(), (int) $data['file_source']);
 
 			$owner = $path->getOwner();
 			$share->setShareOwner($owner->getUID());
@@ -903,7 +903,7 @@ 
 			}
 		}
 
-		$share->setNodeId((int)$data['file_source']);
+		$share->setNodeId((int) $data['file_source']);
 		$share->setNodeType($data['item_type']);
 
 		$share->setProviderId($this->identifier());
@@ -1022,7 +1022,7 @@ 
 			);
 		}
 
-		$qb->innerJoin('s', 'filecache' ,'f', $qb->expr()->eq('s.file_source', 'f.fileid'));
+		$qb->innerJoin('s', 'filecache', 'f', $qb->expr()->eq('s.file_source', 'f.fileid'));
 		$qb->andWhere($qb->expr()->eq('f.parent', $qb->createNamedParameter($node->getId())));
 
 		$qb->orderBy('id');

Indentation +998 added lines, -998 removed lines

@@ -53,1016 +53,1016 @@
  */
 class ShareByMailProvider implements IShareProvider {
 
-	/** @var  IDBConnection */
-	private $dbConnection;
-
-	/** @var ILogger */
-	private $logger;
-
-	/** @var ISecureRandom */
-	private $secureRandom;
-
-	/** @var IUserManager */
-	private $userManager;
-
-	/** @var IRootFolder */
-	private $rootFolder;
-
-	/** @var IL10N */
-	private $l;
-
-	/** @var IMailer */
-	private $mailer;
-
-	/** @var IURLGenerator */
-	private $urlGenerator;
-
-	/** @var IManager  */
-	private $activityManager;
-
-	/** @var SettingsManager */
-	private $settingsManager;
-
-	/** @var Defaults */
-	private $defaults;
-
-	/** @var IHasher */
-	private $hasher;
-
-	/** @var  CapabilitiesManager */
-	private $capabilitiesManager;
-
-	/**
-	 * Return the identifier of this provider.
-	 *
-	 * @return string Containing only [a-zA-Z0-9]
-	 */
-	public function identifier() {
-		return 'ocMailShare';
-	}
-
-	/**
-	 * DefaultShareProvider constructor.
-	 *
-	 * @param IDBConnection $connection
-	 * @param ISecureRandom $secureRandom
-	 * @param IUserManager $userManager
-	 * @param IRootFolder $rootFolder
-	 * @param IL10N $l
-	 * @param ILogger $logger
-	 * @param IMailer $mailer
-	 * @param IURLGenerator $urlGenerator
-	 * @param IManager $activityManager
-	 * @param SettingsManager $settingsManager
-	 * @param Defaults $defaults
-	 * @param IHasher $hasher
-	 * @param CapabilitiesManager $capabilitiesManager
-	 */
-	public function __construct(
-		IDBConnection $connection,
-		ISecureRandom $secureRandom,
-		IUserManager $userManager,
-		IRootFolder $rootFolder,
-		IL10N $l,
-		ILogger $logger,
-		IMailer $mailer,
-		IURLGenerator $urlGenerator,
-		IManager $activityManager,
-		SettingsManager $settingsManager,
-		Defaults $defaults,
-		IHasher $hasher,
-		CapabilitiesManager $capabilitiesManager
-	) {
-		$this->dbConnection = $connection;
-		$this->secureRandom = $secureRandom;
-		$this->userManager = $userManager;
-		$this->rootFolder = $rootFolder;
-		$this->l = $l;
-		$this->logger = $logger;
-		$this->mailer = $mailer;
-		$this->urlGenerator = $urlGenerator;
-		$this->activityManager = $activityManager;
-		$this->settingsManager = $settingsManager;
-		$this->defaults = $defaults;
-		$this->hasher = $hasher;
-		$this->capabilitiesManager = $capabilitiesManager;
-	}
-
-	/**
-	 * Share a path
-	 *
-	 * @param IShare $share
-	 * @return IShare The share object
-	 * @throws ShareNotFound
-	 * @throws \Exception
-	 */
-	public function create(IShare $share) {
-
-		$shareWith = $share->getSharedWith();
-		/*
+    /** @var  IDBConnection */
+    private $dbConnection;
+
+    /** @var ILogger */
+    private $logger;
+
+    /** @var ISecureRandom */
+    private $secureRandom;
+
+    /** @var IUserManager */
+    private $userManager;
+
+    /** @var IRootFolder */
+    private $rootFolder;
+
+    /** @var IL10N */
+    private $l;
+
+    /** @var IMailer */
+    private $mailer;
+
+    /** @var IURLGenerator */
+    private $urlGenerator;
+
+    /** @var IManager  */
+    private $activityManager;
+
+    /** @var SettingsManager */
+    private $settingsManager;
+
+    /** @var Defaults */
+    private $defaults;
+
+    /** @var IHasher */
+    private $hasher;
+
+    /** @var  CapabilitiesManager */
+    private $capabilitiesManager;
+
+    /**
+     * Return the identifier of this provider.
+     *
+     * @return string Containing only [a-zA-Z0-9]
+     */
+    public function identifier() {
+        return 'ocMailShare';
+    }
+
+    /**
+     * DefaultShareProvider constructor.
+     *
+     * @param IDBConnection $connection
+     * @param ISecureRandom $secureRandom
+     * @param IUserManager $userManager
+     * @param IRootFolder $rootFolder
+     * @param IL10N $l
+     * @param ILogger $logger
+     * @param IMailer $mailer
+     * @param IURLGenerator $urlGenerator
+     * @param IManager $activityManager
+     * @param SettingsManager $settingsManager
+     * @param Defaults $defaults
+     * @param IHasher $hasher
+     * @param CapabilitiesManager $capabilitiesManager
+     */
+    public function __construct(
+        IDBConnection $connection,
+        ISecureRandom $secureRandom,
+        IUserManager $userManager,
+        IRootFolder $rootFolder,
+        IL10N $l,
+        ILogger $logger,
+        IMailer $mailer,
+        IURLGenerator $urlGenerator,
+        IManager $activityManager,
+        SettingsManager $settingsManager,
+        Defaults $defaults,
+        IHasher $hasher,
+        CapabilitiesManager $capabilitiesManager
+    ) {
+        $this->dbConnection = $connection;
+        $this->secureRandom = $secureRandom;
+        $this->userManager = $userManager;
+        $this->rootFolder = $rootFolder;
+        $this->l = $l;
+        $this->logger = $logger;
+        $this->mailer = $mailer;
+        $this->urlGenerator = $urlGenerator;
+        $this->activityManager = $activityManager;
+        $this->settingsManager = $settingsManager;
+        $this->defaults = $defaults;
+        $this->hasher = $hasher;
+        $this->capabilitiesManager = $capabilitiesManager;
+    }
+
+    /**
+     * Share a path
+     *
+     * @param IShare $share
+     * @return IShare The share object
+     * @throws ShareNotFound
+     * @throws \Exception
+     */
+    public function create(IShare $share) {
+
+        $shareWith = $share->getSharedWith();
+        /*
 		 * Check if file is not already shared with the remote user
 		 */
-		$alreadyShared = $this->getSharedWith($shareWith, \OCP\Share::SHARE_TYPE_EMAIL, $share->getNode(), 1, 0);
-		if (!empty($alreadyShared)) {
-			$message = 'Sharing %s failed, this item is already shared with %s';
-			$message_t = $this->l->t('Sharing %s failed, this item is already shared with %s', array($share->getNode()->getName(), $shareWith));
-			$this->logger->debug(sprintf($message, $share->getNode()->getName(), $shareWith), ['app' => 'Federated File Sharing']);
-			throw new \Exception($message_t);
-		}
-
-		// if the admin enforces a password for all mail shares we create a
-		// random password and send it to the recipient
-		$password = '';
-		$passwordEnforced = $this->settingsManager->enforcePasswordProtection();
-		if ($passwordEnforced) {
-			$password = $this->autoGeneratePassword($share);
-		}
-
-		$shareId = $this->createMailShare($share);
-		$send = $this->sendPassword($share, $password);
-		if ($passwordEnforced && $send === false) {
-			$this->sendPasswordToOwner($share, $password);
-		}
-
-		$this->createShareActivity($share);
-		$data = $this->getRawShare($shareId);
-
-		return $this->createShareObject($data);
-
-	}
-
-	/**
-	 * auto generate password in case of password enforcement on mail shares
-	 *
-	 * @param IShare $share
-	 * @return string
-	 * @throws \Exception
-	 */
-	protected function autoGeneratePassword($share) {
-		$initiatorUser = $this->userManager->get($share->getSharedBy());
-		$initiatorEMailAddress = ($initiatorUser instanceof IUser) ? $initiatorUser->getEMailAddress() : null;
-		$allowPasswordByMail = $this->settingsManager->sendPasswordByMail();
-
-		if ($initiatorEMailAddress === null && !$allowPasswordByMail) {
-			throw new \Exception(
-				$this->l->t("We can't send you the auto-generated password. Please set a valid email address in your personal settings and try again.")
-			);
-		}
-
-		$passwordPolicy = $this->getPasswordPolicy();
-		$passwordCharset = ISecureRandom::CHAR_LOWER . ISecureRandom::CHAR_UPPER . ISecureRandom::CHAR_DIGITS;
-		$passwordLength = 8;
-		if (!empty($passwordPolicy)) {
-			$passwordLength = (int)$passwordPolicy['minLength'] > 0 ? (int)$passwordPolicy['minLength'] : $passwordLength;
-			$passwordCharset .= $passwordPolicy['enforceSpecialCharacters'] ? ISecureRandom::CHAR_SYMBOLS : '';
-		}
-
-		$password = $this->secureRandom->generate($passwordLength, $passwordCharset);
-
-		$share->setPassword($this->hasher->hash($password));
-
-		return $password;
-	}
-
-	/**
-	 * get password policy
-	 *
-	 * @return array
-	 */
-	protected function getPasswordPolicy() {
-		$capabilities = $this->capabilitiesManager->getCapabilities();
-		if (isset($capabilities['password_policy'])) {
-			return $capabilities['password_policy'];
-		}
-
-		return [];
-	}
-
-	/**
-	 * create activity if a file/folder was shared by mail
-	 *
-	 * @param IShare $share
-	 */
-	protected function createShareActivity(IShare $share) {
-
-		$userFolder = $this->rootFolder->getUserFolder($share->getSharedBy());
-
-		$this->publishActivity(
-			Activity::SUBJECT_SHARED_EMAIL_SELF,
-			[$userFolder->getRelativePath($share->getNode()->getPath()), $share->getSharedWith()],
-			$share->getSharedBy(),
-			$share->getNode()->getId(),
-			$userFolder->getRelativePath($share->getNode()->getPath())
-		);
-
-		if ($share->getShareOwner() !== $share->getSharedBy()) {
-			$ownerFolder = $this->rootFolder->getUserFolder($share->getShareOwner());
-			$fileId = $share->getNode()->getId();
-			$nodes = $ownerFolder->getById($fileId);
-			$ownerPath = $nodes[0]->getPath();
-			$this->publishActivity(
-				Activity::SUBJECT_SHARED_EMAIL_BY,
-				[$ownerFolder->getRelativePath($ownerPath), $share->getSharedWith(), $share->getSharedBy()],
-				$share->getShareOwner(),
-				$fileId,
-				$ownerFolder->getRelativePath($ownerPath)
-			);
-		}
-
-	}
-
-	/**
-	 * create activity if a file/folder was shared by mail
-	 *
-	 * @param IShare $share
-	 * @param string $sharedWith
-	 * @param bool $sendToSelf
-	 */
-	protected function createPasswordSendActivity(IShare $share, $sharedWith, $sendToSelf) {
-
-		$userFolder = $this->rootFolder->getUserFolder($share->getSharedBy());
-
-		if ($sendToSelf) {
-			$this->publishActivity(
-				Activity::SUBJECT_SHARED_EMAIL_PASSWORD_SEND_SELF,
-				[$userFolder->getRelativePath($share->getNode()->getPath())],
-				$share->getSharedBy(),
-				$share->getNode()->getId(),
-				$userFolder->getRelativePath($share->getNode()->getPath())
-			);
-		} else {
-			$this->publishActivity(
-				Activity::SUBJECT_SHARED_EMAIL_PASSWORD_SEND,
-				[$userFolder->getRelativePath($share->getNode()->getPath()), $sharedWith],
-				$share->getSharedBy(),
-				$share->getNode()->getId(),
-				$userFolder->getRelativePath($share->getNode()->getPath())
-			);
-		}
-	}
-
-
-	/**
-	 * publish activity if a file/folder was shared by mail
-	 *
-	 * @param $subject
-	 * @param $parameters
-	 * @param $affectedUser
-	 * @param $fileId
-	 * @param $filePath
-	 */
-	protected function publishActivity($subject, $parameters, $affectedUser, $fileId, $filePath) {
-		$event = $this->activityManager->generateEvent();
-		$event->setApp('sharebymail')
-			->setType('shared')
-			->setSubject($subject, $parameters)
-			->setAffectedUser($affectedUser)
-			->setObject('files', $fileId, $filePath);
-		$this->activityManager->publish($event);
-
-	}
-
-	/**
-	 * @param IShare $share
-	 * @return int
-	 * @throws \Exception
-	 */
-	protected function createMailShare(IShare $share) {
-		$share->setToken($this->generateToken());
-		$shareId = $this->addShareToDB(
-			$share->getNodeId(),
-			$share->getNodeType(),
-			$share->getSharedWith(),
-			$share->getSharedBy(),
-			$share->getShareOwner(),
-			$share->getPermissions(),
-			$share->getToken(),
-			$share->getPassword()
-		);
-
-		try {
-			$link = $this->urlGenerator->linkToRouteAbsolute('files_sharing.sharecontroller.showShare',
-				['token' => $share->getToken()]);
-			$this->sendMailNotification(
-				$share->getNode()->getName(),
-				$link,
-				$share->getSharedBy(),
-				$share->getSharedWith()
-			);
-		} catch (HintException $hintException) {
-			$this->logger->error('Failed to send share by mail: ' . $hintException->getMessage());
-			$this->removeShareFromTable($shareId);
-			throw $hintException;
-		} catch (\Exception $e) {
-			$this->logger->error('Failed to send share by email: ' . $e->getMessage());
-			$this->removeShareFromTable($shareId);
-			throw new HintException('Failed to send share by mail',
-				$this->l->t('Failed to send share by email'));
-		}
-
-		return $shareId;
-
-	}
-
-	/**
-	 * @param string $filename
-	 * @param string $link
-	 * @param string $initiator
-	 * @param string $shareWith
-	 * @throws \Exception If mail couldn't be sent
-	 */
-	protected function sendMailNotification($filename,
-											$link,
-											$initiator,
-											$shareWith) {
-		$initiatorUser = $this->userManager->get($initiator);
-		$initiatorDisplayName = ($initiatorUser instanceof IUser) ? $initiatorUser->getDisplayName() : $initiator;
-		$subject = (string)$this->l->t('%s shared »%s« with you', array($initiatorDisplayName, $filename));
-
-		$message = $this->mailer->createMessage();
-
-		$emailTemplate = $this->mailer->createEMailTemplate();
-
-		$emailTemplate->addHeader();
-		$emailTemplate->addHeading($this->l->t('%s shared »%s« with you', [$initiatorDisplayName, $filename]), false);
-		$text = $this->l->t('%s shared »%s« with you.', [$initiatorDisplayName, $filename]);
-
-		$emailTemplate->addBodyText(
-			$text . ' ' . $this->l->t('Click the button below to open it.'),
-			$text
-		);
-		$emailTemplate->addBodyButton(
-			$this->l->t('Open »%s«', [$filename]),
-			$link
-		);
-
-		$message->setTo([$shareWith]);
-
-		// The "From" contains the sharers name
-		$instanceName = $this->defaults->getName();
-		$senderName = $this->l->t(
-			'%s via %s',
-			[
-				$initiatorDisplayName,
-				$instanceName
-			]
-		);
-		$message->setFrom([\OCP\Util::getDefaultEmailAddress($instanceName) => $senderName]);
-
-		// The "Reply-To" is set to the sharer if an mail address is configured
-		// also the default footer contains a "Do not reply" which needs to be adjusted.
-		$initiatorEmail = $initiatorUser->getEMailAddress();
-		if($initiatorEmail !== null) {
-			$message->setReplyTo([$initiatorEmail => $initiatorDisplayName]);
-			$emailTemplate->addFooter($instanceName . ' - ' . $this->defaults->getSlogan());
-		} else {
-			$emailTemplate->addFooter();
-		}
-
-		$message->setSubject($subject);
-		$message->setPlainBody($emailTemplate->renderText());
-		$message->setHtmlBody($emailTemplate->renderHtml());
-		$this->mailer->send($message);
-	}
-
-	/**
-	 * send password to recipient of a mail share
-	 *
-	 * @param IShare $share
-	 * @param string $password
-	 * @return bool
-	 */
-	protected function sendPassword(IShare $share, $password) {
-
-		$filename = $share->getNode()->getName();
-		$initiator = $share->getSharedBy();
-		$shareWith = $share->getSharedWith();
-
-		if ($password === '' || $this->settingsManager->sendPasswordByMail() === false) {
-			return false;
-		}
-
-		$initiatorUser = $this->userManager->get($initiator);
-		$initiatorDisplayName = ($initiatorUser instanceof IUser) ? $initiatorUser->getDisplayName() : $initiator;
-		$initiatorEmailAddress = ($initiatorUser instanceof IUser) ? $initiatorUser->getEMailAddress() : null;
-
-		$subject = (string)$this->l->t('Password to access »%s« shared to you by %s', [$filename, $initiatorDisplayName]);
-		$plainBodyPart = $this->l->t("%s shared »%s« with you.\nYou should have already received a separate mail with a link to access it.\n", [$initiatorDisplayName, $filename]);
-		$htmlBodyPart = $this->l->t('%s shared »%s« with you. You should have already received a separate mail with a link to access it.', [$initiatorDisplayName, $filename]);
-
-		$message = $this->mailer->createMessage();
-
-		$emailTemplate = $this->mailer->createEMailTemplate();
-		$emailTemplate->addHeader();
-		$emailTemplate->addHeading($this->l->t('Password to access »%s«', [$filename]), false);
-		$emailTemplate->addBodyText($htmlBodyPart, $plainBodyPart);
-		$emailTemplate->addBodyText($this->l->t('It is protected with the following password: %s', [$password]));
-
-		// The "From" contains the sharers name
-		$instanceName = $this->defaults->getName();
-		$senderName = $this->l->t(
-			'%s via %s',
-			[
-				$initiatorDisplayName,
-				$instanceName
-			]
-		);
-		$message->setFrom([\OCP\Util::getDefaultEmailAddress($instanceName) => $senderName]);
-		if ($initiatorEmailAddress !== null) {
-			$message->setReplyTo([$initiatorEmailAddress => $initiatorDisplayName]);
-			$emailTemplate->addFooter($instanceName . ' - ' . $this->defaults->getSlogan());
-		} else {
-			$emailTemplate->addFooter();
-		}
-
-		$message->setTo([$shareWith]);
-		$message->setSubject($subject);
-		$message->setBody($emailTemplate->renderText(), 'text/plain');
-		$message->setHtmlBody($emailTemplate->renderHtml());
-		$this->mailer->send($message);
-
-		$this->createPasswordSendActivity($share, $shareWith, false);
-
-		return true;
-	}
-
-	/**
-	 * send auto generated password to the owner. This happens if the admin enforces
-	 * a password for mail shares and forbid to send the password by mail to the recipient
-	 *
-	 * @param IShare $share
-	 * @param string $password
-	 * @return bool
-	 * @throws \Exception
-	 */
-	protected function sendPasswordToOwner(IShare $share, $password) {
-
-		$filename = $share->getNode()->getName();
-		$initiator = $this->userManager->get($share->getSharedBy());
-		$initiatorEMailAddress = ($initiator instanceof IUser) ? $initiator->getEMailAddress() : null;
-		$initiatorDisplayName = ($initiator instanceof IUser) ? $initiator->getDisplayName() : $share->getSharedBy();
-		$shareWith = $share->getSharedWith();
-
-		if ($initiatorEMailAddress === null) {
-			throw new \Exception(
-				$this->l->t("We can't send you the auto-generated password. Please set a valid email address in your personal settings and try again.")
-			);
-		}
-
-		$subject = (string)$this->l->t('Password to access »%s« shared with %s', [$filename, $shareWith]);
-		$bodyPart = $this->l->t("You just shared »%s« with %s. The share was already send to the recipient. Due to the security policies defined by the administrator of %s each share needs to be protected by password and it is not allowed to send the password directly to the recipient. Therefore you need to forward the password manually to the recipient.", [$filename, $shareWith, $this->defaults->getName()]);
-
-		$message = $this->mailer->createMessage();
-		$emailTemplate = $this->mailer->createEMailTemplate();
-
-		$emailTemplate->addHeader();
-		$emailTemplate->addHeading($this->l->t('Password to access »%s«', [$filename]), false);
-		$emailTemplate->addBodyText($bodyPart);
-		$emailTemplate->addBodyText($this->l->t('This is the password: %s', [$password]));
-		$emailTemplate->addBodyText($this->l->t('You can choose a different password at any time in the share dialog.'));
-		$emailTemplate->addFooter();
-
-		if ($initiatorEMailAddress) {
-			$message->setFrom([$initiatorEMailAddress => $initiatorDisplayName]);
-		}
-		$message->setTo([$initiatorEMailAddress => $initiatorDisplayName]);
-		$message->setSubject($subject);
-		$message->setBody($emailTemplate->renderText(), 'text/plain');
-		$message->setHtmlBody($emailTemplate->renderHtml());
-		$this->mailer->send($message);
-
-		$this->createPasswordSendActivity($share, $shareWith, true);
-
-		return true;
-	}
-
-	/**
-	 * generate share token
-	 *
-	 * @return string
-	 */
-	protected function generateToken($size = 15) {
-		$token = $this->secureRandom->generate($size, ISecureRandom::CHAR_HUMAN_READABLE);
-		return $token;
-	}
-
-	/**
-	 * Get all children of this share
-	 *
-	 * @param IShare $parent
-	 * @return IShare[]
-	 */
-	public function getChildren(IShare $parent) {
-		$children = [];
-
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('*')
-			->from('share')
-			->where($qb->expr()->eq('parent', $qb->createNamedParameter($parent->getId())))
-			->andWhere($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)))
-			->orderBy('id');
-
-		$cursor = $qb->execute();
-		while($data = $cursor->fetch()) {
-			$children[] = $this->createShareObject($data);
-		}
-		$cursor->closeCursor();
-
-		return $children;
-	}
-
-	/**
-	 * add share to the database and return the ID
-	 *
-	 * @param int $itemSource
-	 * @param string $itemType
-	 * @param string $shareWith
-	 * @param string $sharedBy
-	 * @param string $uidOwner
-	 * @param int $permissions
-	 * @param string $token
-	 * @return int
-	 */
-	protected function addShareToDB($itemSource, $itemType, $shareWith, $sharedBy, $uidOwner, $permissions, $token, $password) {
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->insert('share')
-			->setValue('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL))
-			->setValue('item_type', $qb->createNamedParameter($itemType))
-			->setValue('item_source', $qb->createNamedParameter($itemSource))
-			->setValue('file_source', $qb->createNamedParameter($itemSource))
-			->setValue('share_with', $qb->createNamedParameter($shareWith))
-			->setValue('uid_owner', $qb->createNamedParameter($uidOwner))
-			->setValue('uid_initiator', $qb->createNamedParameter($sharedBy))
-			->setValue('permissions', $qb->createNamedParameter($permissions))
-			->setValue('token', $qb->createNamedParameter($token))
-			->setValue('password', $qb->createNamedParameter($password))
-			->setValue('stime', $qb->createNamedParameter(time()));
-
-		/*
+        $alreadyShared = $this->getSharedWith($shareWith, \OCP\Share::SHARE_TYPE_EMAIL, $share->getNode(), 1, 0);
+        if (!empty($alreadyShared)) {
+            $message = 'Sharing %s failed, this item is already shared with %s';
+            $message_t = $this->l->t('Sharing %s failed, this item is already shared with %s', array($share->getNode()->getName(), $shareWith));
+            $this->logger->debug(sprintf($message, $share->getNode()->getName(), $shareWith), ['app' => 'Federated File Sharing']);
+            throw new \Exception($message_t);
+        }
+
+        // if the admin enforces a password for all mail shares we create a
+        // random password and send it to the recipient
+        $password = '';
+        $passwordEnforced = $this->settingsManager->enforcePasswordProtection();
+        if ($passwordEnforced) {
+            $password = $this->autoGeneratePassword($share);
+        }
+
+        $shareId = $this->createMailShare($share);
+        $send = $this->sendPassword($share, $password);
+        if ($passwordEnforced && $send === false) {
+            $this->sendPasswordToOwner($share, $password);
+        }
+
+        $this->createShareActivity($share);
+        $data = $this->getRawShare($shareId);
+
+        return $this->createShareObject($data);
+
+    }
+
+    /**
+     * auto generate password in case of password enforcement on mail shares
+     *
+     * @param IShare $share
+     * @return string
+     * @throws \Exception
+     */
+    protected function autoGeneratePassword($share) {
+        $initiatorUser = $this->userManager->get($share->getSharedBy());
+        $initiatorEMailAddress = ($initiatorUser instanceof IUser) ? $initiatorUser->getEMailAddress() : null;
+        $allowPasswordByMail = $this->settingsManager->sendPasswordByMail();
+
+        if ($initiatorEMailAddress === null && !$allowPasswordByMail) {
+            throw new \Exception(
+                $this->l->t("We can't send you the auto-generated password. Please set a valid email address in your personal settings and try again.")
+            );
+        }
+
+        $passwordPolicy = $this->getPasswordPolicy();
+        $passwordCharset = ISecureRandom::CHAR_LOWER . ISecureRandom::CHAR_UPPER . ISecureRandom::CHAR_DIGITS;
+        $passwordLength = 8;
+        if (!empty($passwordPolicy)) {
+            $passwordLength = (int)$passwordPolicy['minLength'] > 0 ? (int)$passwordPolicy['minLength'] : $passwordLength;
+            $passwordCharset .= $passwordPolicy['enforceSpecialCharacters'] ? ISecureRandom::CHAR_SYMBOLS : '';
+        }
+
+        $password = $this->secureRandom->generate($passwordLength, $passwordCharset);
+
+        $share->setPassword($this->hasher->hash($password));
+
+        return $password;
+    }
+
+    /**
+     * get password policy
+     *
+     * @return array
+     */
+    protected function getPasswordPolicy() {
+        $capabilities = $this->capabilitiesManager->getCapabilities();
+        if (isset($capabilities['password_policy'])) {
+            return $capabilities['password_policy'];
+        }
+
+        return [];
+    }
+
+    /**
+     * create activity if a file/folder was shared by mail
+     *
+     * @param IShare $share
+     */
+    protected function createShareActivity(IShare $share) {
+
+        $userFolder = $this->rootFolder->getUserFolder($share->getSharedBy());
+
+        $this->publishActivity(
+            Activity::SUBJECT_SHARED_EMAIL_SELF,
+            [$userFolder->getRelativePath($share->getNode()->getPath()), $share->getSharedWith()],
+            $share->getSharedBy(),
+            $share->getNode()->getId(),
+            $userFolder->getRelativePath($share->getNode()->getPath())
+        );
+
+        if ($share->getShareOwner() !== $share->getSharedBy()) {
+            $ownerFolder = $this->rootFolder->getUserFolder($share->getShareOwner());
+            $fileId = $share->getNode()->getId();
+            $nodes = $ownerFolder->getById($fileId);
+            $ownerPath = $nodes[0]->getPath();
+            $this->publishActivity(
+                Activity::SUBJECT_SHARED_EMAIL_BY,
+                [$ownerFolder->getRelativePath($ownerPath), $share->getSharedWith(), $share->getSharedBy()],
+                $share->getShareOwner(),
+                $fileId,
+                $ownerFolder->getRelativePath($ownerPath)
+            );
+        }
+
+    }
+
+    /**
+     * create activity if a file/folder was shared by mail
+     *
+     * @param IShare $share
+     * @param string $sharedWith
+     * @param bool $sendToSelf
+     */
+    protected function createPasswordSendActivity(IShare $share, $sharedWith, $sendToSelf) {
+
+        $userFolder = $this->rootFolder->getUserFolder($share->getSharedBy());
+
+        if ($sendToSelf) {
+            $this->publishActivity(
+                Activity::SUBJECT_SHARED_EMAIL_PASSWORD_SEND_SELF,
+                [$userFolder->getRelativePath($share->getNode()->getPath())],
+                $share->getSharedBy(),
+                $share->getNode()->getId(),
+                $userFolder->getRelativePath($share->getNode()->getPath())
+            );
+        } else {
+            $this->publishActivity(
+                Activity::SUBJECT_SHARED_EMAIL_PASSWORD_SEND,
+                [$userFolder->getRelativePath($share->getNode()->getPath()), $sharedWith],
+                $share->getSharedBy(),
+                $share->getNode()->getId(),
+                $userFolder->getRelativePath($share->getNode()->getPath())
+            );
+        }
+    }
+
+
+    /**
+     * publish activity if a file/folder was shared by mail
+     *
+     * @param $subject
+     * @param $parameters
+     * @param $affectedUser
+     * @param $fileId
+     * @param $filePath
+     */
+    protected function publishActivity($subject, $parameters, $affectedUser, $fileId, $filePath) {
+        $event = $this->activityManager->generateEvent();
+        $event->setApp('sharebymail')
+            ->setType('shared')
+            ->setSubject($subject, $parameters)
+            ->setAffectedUser($affectedUser)
+            ->setObject('files', $fileId, $filePath);
+        $this->activityManager->publish($event);
+
+    }
+
+    /**
+     * @param IShare $share
+     * @return int
+     * @throws \Exception
+     */
+    protected function createMailShare(IShare $share) {
+        $share->setToken($this->generateToken());
+        $shareId = $this->addShareToDB(
+            $share->getNodeId(),
+            $share->getNodeType(),
+            $share->getSharedWith(),
+            $share->getSharedBy(),
+            $share->getShareOwner(),
+            $share->getPermissions(),
+            $share->getToken(),
+            $share->getPassword()
+        );
+
+        try {
+            $link = $this->urlGenerator->linkToRouteAbsolute('files_sharing.sharecontroller.showShare',
+                ['token' => $share->getToken()]);
+            $this->sendMailNotification(
+                $share->getNode()->getName(),
+                $link,
+                $share->getSharedBy(),
+                $share->getSharedWith()
+            );
+        } catch (HintException $hintException) {
+            $this->logger->error('Failed to send share by mail: ' . $hintException->getMessage());
+            $this->removeShareFromTable($shareId);
+            throw $hintException;
+        } catch (\Exception $e) {
+            $this->logger->error('Failed to send share by email: ' . $e->getMessage());
+            $this->removeShareFromTable($shareId);
+            throw new HintException('Failed to send share by mail',
+                $this->l->t('Failed to send share by email'));
+        }
+
+        return $shareId;
+
+    }
+
+    /**
+     * @param string $filename
+     * @param string $link
+     * @param string $initiator
+     * @param string $shareWith
+     * @throws \Exception If mail couldn't be sent
+     */
+    protected function sendMailNotification($filename,
+                                            $link,
+                                            $initiator,
+                                            $shareWith) {
+        $initiatorUser = $this->userManager->get($initiator);
+        $initiatorDisplayName = ($initiatorUser instanceof IUser) ? $initiatorUser->getDisplayName() : $initiator;
+        $subject = (string)$this->l->t('%s shared »%s« with you', array($initiatorDisplayName, $filename));
+
+        $message = $this->mailer->createMessage();
+
+        $emailTemplate = $this->mailer->createEMailTemplate();
+
+        $emailTemplate->addHeader();
+        $emailTemplate->addHeading($this->l->t('%s shared »%s« with you', [$initiatorDisplayName, $filename]), false);
+        $text = $this->l->t('%s shared »%s« with you.', [$initiatorDisplayName, $filename]);
+
+        $emailTemplate->addBodyText(
+            $text . ' ' . $this->l->t('Click the button below to open it.'),
+            $text
+        );
+        $emailTemplate->addBodyButton(
+            $this->l->t('Open »%s«', [$filename]),
+            $link
+        );
+
+        $message->setTo([$shareWith]);
+
+        // The "From" contains the sharers name
+        $instanceName = $this->defaults->getName();
+        $senderName = $this->l->t(
+            '%s via %s',
+            [
+                $initiatorDisplayName,
+                $instanceName
+            ]
+        );
+        $message->setFrom([\OCP\Util::getDefaultEmailAddress($instanceName) => $senderName]);
+
+        // The "Reply-To" is set to the sharer if an mail address is configured
+        // also the default footer contains a "Do not reply" which needs to be adjusted.
+        $initiatorEmail = $initiatorUser->getEMailAddress();
+        if($initiatorEmail !== null) {
+            $message->setReplyTo([$initiatorEmail => $initiatorDisplayName]);
+            $emailTemplate->addFooter($instanceName . ' - ' . $this->defaults->getSlogan());
+        } else {
+            $emailTemplate->addFooter();
+        }
+
+        $message->setSubject($subject);
+        $message->setPlainBody($emailTemplate->renderText());
+        $message->setHtmlBody($emailTemplate->renderHtml());
+        $this->mailer->send($message);
+    }
+
+    /**
+     * send password to recipient of a mail share
+     *
+     * @param IShare $share
+     * @param string $password
+     * @return bool
+     */
+    protected function sendPassword(IShare $share, $password) {
+
+        $filename = $share->getNode()->getName();
+        $initiator = $share->getSharedBy();
+        $shareWith = $share->getSharedWith();
+
+        if ($password === '' || $this->settingsManager->sendPasswordByMail() === false) {
+            return false;
+        }
+
+        $initiatorUser = $this->userManager->get($initiator);
+        $initiatorDisplayName = ($initiatorUser instanceof IUser) ? $initiatorUser->getDisplayName() : $initiator;
+        $initiatorEmailAddress = ($initiatorUser instanceof IUser) ? $initiatorUser->getEMailAddress() : null;
+
+        $subject = (string)$this->l->t('Password to access »%s« shared to you by %s', [$filename, $initiatorDisplayName]);
+        $plainBodyPart = $this->l->t("%s shared »%s« with you.\nYou should have already received a separate mail with a link to access it.\n", [$initiatorDisplayName, $filename]);
+        $htmlBodyPart = $this->l->t('%s shared »%s« with you. You should have already received a separate mail with a link to access it.', [$initiatorDisplayName, $filename]);
+
+        $message = $this->mailer->createMessage();
+
+        $emailTemplate = $this->mailer->createEMailTemplate();
+        $emailTemplate->addHeader();
+        $emailTemplate->addHeading($this->l->t('Password to access »%s«', [$filename]), false);
+        $emailTemplate->addBodyText($htmlBodyPart, $plainBodyPart);
+        $emailTemplate->addBodyText($this->l->t('It is protected with the following password: %s', [$password]));
+
+        // The "From" contains the sharers name
+        $instanceName = $this->defaults->getName();
+        $senderName = $this->l->t(
+            '%s via %s',
+            [
+                $initiatorDisplayName,
+                $instanceName
+            ]
+        );
+        $message->setFrom([\OCP\Util::getDefaultEmailAddress($instanceName) => $senderName]);
+        if ($initiatorEmailAddress !== null) {
+            $message->setReplyTo([$initiatorEmailAddress => $initiatorDisplayName]);
+            $emailTemplate->addFooter($instanceName . ' - ' . $this->defaults->getSlogan());
+        } else {
+            $emailTemplate->addFooter();
+        }
+
+        $message->setTo([$shareWith]);
+        $message->setSubject($subject);
+        $message->setBody($emailTemplate->renderText(), 'text/plain');
+        $message->setHtmlBody($emailTemplate->renderHtml());
+        $this->mailer->send($message);
+
+        $this->createPasswordSendActivity($share, $shareWith, false);
+
+        return true;
+    }
+
+    /**
+     * send auto generated password to the owner. This happens if the admin enforces
+     * a password for mail shares and forbid to send the password by mail to the recipient
+     *
+     * @param IShare $share
+     * @param string $password
+     * @return bool
+     * @throws \Exception
+     */
+    protected function sendPasswordToOwner(IShare $share, $password) {
+
+        $filename = $share->getNode()->getName();
+        $initiator = $this->userManager->get($share->getSharedBy());
+        $initiatorEMailAddress = ($initiator instanceof IUser) ? $initiator->getEMailAddress() : null;
+        $initiatorDisplayName = ($initiator instanceof IUser) ? $initiator->getDisplayName() : $share->getSharedBy();
+        $shareWith = $share->getSharedWith();
+
+        if ($initiatorEMailAddress === null) {
+            throw new \Exception(
+                $this->l->t("We can't send you the auto-generated password. Please set a valid email address in your personal settings and try again.")
+            );
+        }
+
+        $subject = (string)$this->l->t('Password to access »%s« shared with %s', [$filename, $shareWith]);
+        $bodyPart = $this->l->t("You just shared »%s« with %s. The share was already send to the recipient. Due to the security policies defined by the administrator of %s each share needs to be protected by password and it is not allowed to send the password directly to the recipient. Therefore you need to forward the password manually to the recipient.", [$filename, $shareWith, $this->defaults->getName()]);
+
+        $message = $this->mailer->createMessage();
+        $emailTemplate = $this->mailer->createEMailTemplate();
+
+        $emailTemplate->addHeader();
+        $emailTemplate->addHeading($this->l->t('Password to access »%s«', [$filename]), false);
+        $emailTemplate->addBodyText($bodyPart);
+        $emailTemplate->addBodyText($this->l->t('This is the password: %s', [$password]));
+        $emailTemplate->addBodyText($this->l->t('You can choose a different password at any time in the share dialog.'));
+        $emailTemplate->addFooter();
+
+        if ($initiatorEMailAddress) {
+            $message->setFrom([$initiatorEMailAddress => $initiatorDisplayName]);
+        }
+        $message->setTo([$initiatorEMailAddress => $initiatorDisplayName]);
+        $message->setSubject($subject);
+        $message->setBody($emailTemplate->renderText(), 'text/plain');
+        $message->setHtmlBody($emailTemplate->renderHtml());
+        $this->mailer->send($message);
+
+        $this->createPasswordSendActivity($share, $shareWith, true);
+
+        return true;
+    }
+
+    /**
+     * generate share token
+     *
+     * @return string
+     */
+    protected function generateToken($size = 15) {
+        $token = $this->secureRandom->generate($size, ISecureRandom::CHAR_HUMAN_READABLE);
+        return $token;
+    }
+
+    /**
+     * Get all children of this share
+     *
+     * @param IShare $parent
+     * @return IShare[]
+     */
+    public function getChildren(IShare $parent) {
+        $children = [];
+
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('*')
+            ->from('share')
+            ->where($qb->expr()->eq('parent', $qb->createNamedParameter($parent->getId())))
+            ->andWhere($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)))
+            ->orderBy('id');
+
+        $cursor = $qb->execute();
+        while($data = $cursor->fetch()) {
+            $children[] = $this->createShareObject($data);
+        }
+        $cursor->closeCursor();
+
+        return $children;
+    }
+
+    /**
+     * add share to the database and return the ID
+     *
+     * @param int $itemSource
+     * @param string $itemType
+     * @param string $shareWith
+     * @param string $sharedBy
+     * @param string $uidOwner
+     * @param int $permissions
+     * @param string $token
+     * @return int
+     */
+    protected function addShareToDB($itemSource, $itemType, $shareWith, $sharedBy, $uidOwner, $permissions, $token, $password) {
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->insert('share')
+            ->setValue('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL))
+            ->setValue('item_type', $qb->createNamedParameter($itemType))
+            ->setValue('item_source', $qb->createNamedParameter($itemSource))
+            ->setValue('file_source', $qb->createNamedParameter($itemSource))
+            ->setValue('share_with', $qb->createNamedParameter($shareWith))
+            ->setValue('uid_owner', $qb->createNamedParameter($uidOwner))
+            ->setValue('uid_initiator', $qb->createNamedParameter($sharedBy))
+            ->setValue('permissions', $qb->createNamedParameter($permissions))
+            ->setValue('token', $qb->createNamedParameter($token))
+            ->setValue('password', $qb->createNamedParameter($password))
+            ->setValue('stime', $qb->createNamedParameter(time()));
+
+        /*
 		 * Added to fix https://github.com/owncloud/core/issues/22215
 		 * Can be removed once we get rid of ajax/share.php
 		 */
-		$qb->setValue('file_target', $qb->createNamedParameter(''));
+        $qb->setValue('file_target', $qb->createNamedParameter(''));
 
-		$qb->execute();
-		$id = $qb->getLastInsertId();
+        $qb->execute();
+        $id = $qb->getLastInsertId();
 
-		return (int)$id;
-	}
+        return (int)$id;
+    }
 
-	/**
-	 * Update a share
-	 *
-	 * @param IShare $share
-	 * @param string|null $plainTextPassword
-	 * @return IShare The share object
-	 */
-	public function update(IShare $share, $plainTextPassword = null) {
+    /**
+     * Update a share
+     *
+     * @param IShare $share
+     * @param string|null $plainTextPassword
+     * @return IShare The share object
+     */
+    public function update(IShare $share, $plainTextPassword = null) {
 
-		$originalShare = $this->getShareById($share->getId());
+        $originalShare = $this->getShareById($share->getId());
 
-		// a real password was given
-		$validPassword = $plainTextPassword !== null && $plainTextPassword !== '';
+        // a real password was given
+        $validPassword = $plainTextPassword !== null && $plainTextPassword !== '';
 
-		if($validPassword && $originalShare->getPassword() !== $share->getPassword()) {
-			$this->sendPassword($share, $plainTextPassword);
-		}
-		/*
+        if($validPassword && $originalShare->getPassword() !== $share->getPassword()) {
+            $this->sendPassword($share, $plainTextPassword);
+        }
+        /*
 		 * We allow updating the permissions and password of mail shares
 		 */
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->update('share')
-			->where($qb->expr()->eq('id', $qb->createNamedParameter($share->getId())))
-			->set('permissions', $qb->createNamedParameter($share->getPermissions()))
-			->set('uid_owner', $qb->createNamedParameter($share->getShareOwner()))
-			->set('uid_initiator', $qb->createNamedParameter($share->getSharedBy()))
-			->set('password', $qb->createNamedParameter($share->getPassword()))
-			->set('expiration', $qb->createNamedParameter($share->getExpirationDate(), IQueryBuilder::PARAM_DATE))
-			->execute();
-
-		return $share;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function move(IShare $share, $recipient) {
-		/**
-		 * nothing to do here, mail shares are only outgoing shares
-		 */
-		return $share;
-	}
-
-	/**
-	 * Delete a share (owner unShares the file)
-	 *
-	 * @param IShare $share
-	 */
-	public function delete(IShare $share) {
-		$this->removeShareFromTable($share->getId());
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function deleteFromSelf(IShare $share, $recipient) {
-		// nothing to do here, mail shares are only outgoing shares
-		return;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function getSharesBy($userId, $shareType, $node, $reshares, $limit, $offset) {
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('*')
-			->from('share');
-
-		$qb->andWhere($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)));
-
-		/**
-		 * Reshares for this user are shares where they are the owner.
-		 */
-		if ($reshares === false) {
-			//Special case for old shares created via the web UI
-			$or1 = $qb->expr()->andX(
-				$qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
-				$qb->expr()->isNull('uid_initiator')
-			);
-
-			$qb->andWhere(
-				$qb->expr()->orX(
-					$qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId)),
-					$or1
-				)
-			);
-		} else {
-			$qb->andWhere(
-				$qb->expr()->orX(
-					$qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
-					$qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId))
-				)
-			);
-		}
-
-		if ($node !== null) {
-			$qb->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($node->getId())));
-		}
-
-		if ($limit !== -1) {
-			$qb->setMaxResults($limit);
-		}
-
-		$qb->setFirstResult($offset);
-		$qb->orderBy('id');
-
-		$cursor = $qb->execute();
-		$shares = [];
-		while($data = $cursor->fetch()) {
-			$shares[] = $this->createShareObject($data);
-		}
-		$cursor->closeCursor();
-
-		return $shares;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function getShareById($id, $recipientId = null) {
-		$qb = $this->dbConnection->getQueryBuilder();
-
-		$qb->select('*')
-			->from('share')
-			->where($qb->expr()->eq('id', $qb->createNamedParameter($id)))
-			->andWhere($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)));
-
-		$cursor = $qb->execute();
-		$data = $cursor->fetch();
-		$cursor->closeCursor();
-
-		if ($data === false) {
-			throw new ShareNotFound();
-		}
-
-		try {
-			$share = $this->createShareObject($data);
-		} catch (InvalidShare $e) {
-			throw new ShareNotFound();
-		}
-
-		return $share;
-	}
-
-	/**
-	 * Get shares for a given path
-	 *
-	 * @param \OCP\Files\Node $path
-	 * @return IShare[]
-	 */
-	public function getSharesByPath(Node $path) {
-		$qb = $this->dbConnection->getQueryBuilder();
-
-		$cursor = $qb->select('*')
-			->from('share')
-			->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($path->getId())))
-			->andWhere($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)))
-			->execute();
-
-		$shares = [];
-		while($data = $cursor->fetch()) {
-			$shares[] = $this->createShareObject($data);
-		}
-		$cursor->closeCursor();
-
-		return $shares;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function getSharedWith($userId, $shareType, $node, $limit, $offset) {
-		/** @var IShare[] $shares */
-		$shares = [];
-
-		//Get shares directly with this user
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('*')
-			->from('share');
-
-		// Order by id
-		$qb->orderBy('id');
-
-		// Set limit and offset
-		if ($limit !== -1) {
-			$qb->setMaxResults($limit);
-		}
-		$qb->setFirstResult($offset);
-
-		$qb->where($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)));
-		$qb->andWhere($qb->expr()->eq('share_with', $qb->createNamedParameter($userId)));
-
-		// Filter by node if provided
-		if ($node !== null) {
-			$qb->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($node->getId())));
-		}
-
-		$cursor = $qb->execute();
-
-		while($data = $cursor->fetch()) {
-			$shares[] = $this->createShareObject($data);
-		}
-		$cursor->closeCursor();
-
-
-		return $shares;
-	}
-
-	/**
-	 * Get a share by token
-	 *
-	 * @param string $token
-	 * @return IShare
-	 * @throws ShareNotFound
-	 */
-	public function getShareByToken($token) {
-		$qb = $this->dbConnection->getQueryBuilder();
-
-		$cursor = $qb->select('*')
-			->from('share')
-			->where($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)))
-			->andWhere($qb->expr()->eq('token', $qb->createNamedParameter($token)))
-			->execute();
-
-		$data = $cursor->fetch();
-
-		if ($data === false) {
-			throw new ShareNotFound('Share not found', $this->l->t('Could not find share'));
-		}
-
-		try {
-			$share = $this->createShareObject($data);
-		} catch (InvalidShare $e) {
-			throw new ShareNotFound('Share not found', $this->l->t('Could not find share'));
-		}
-
-		return $share;
-	}
-
-	/**
-	 * remove share from table
-	 *
-	 * @param string $shareId
-	 */
-	protected function removeShareFromTable($shareId) {
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->delete('share')
-			->where($qb->expr()->eq('id', $qb->createNamedParameter($shareId)));
-		$qb->execute();
-	}
-
-	/**
-	 * Create a share object from an database row
-	 *
-	 * @param array $data
-	 * @return IShare
-	 * @throws InvalidShare
-	 * @throws ShareNotFound
-	 */
-	protected function createShareObject($data) {
-
-		$share = new Share($this->rootFolder, $this->userManager);
-		$share->setId((int)$data['id'])
-			->setShareType((int)$data['share_type'])
-			->setPermissions((int)$data['permissions'])
-			->setTarget($data['file_target'])
-			->setMailSend((bool)$data['mail_send'])
-			->setToken($data['token']);
-
-		$shareTime = new \DateTime();
-		$shareTime->setTimestamp((int)$data['stime']);
-		$share->setShareTime($shareTime);
-		$share->setSharedWith($data['share_with']);
-		$share->setPassword($data['password']);
-
-		if ($data['uid_initiator'] !== null) {
-			$share->setShareOwner($data['uid_owner']);
-			$share->setSharedBy($data['uid_initiator']);
-		} else {
-			//OLD SHARE
-			$share->setSharedBy($data['uid_owner']);
-			$path = $this->getNode($share->getSharedBy(), (int)$data['file_source']);
-
-			$owner = $path->getOwner();
-			$share->setShareOwner($owner->getUID());
-		}
-
-		if ($data['expiration'] !== null) {
-			$expiration = \DateTime::createFromFormat('Y-m-d H:i:s', $data['expiration']);
-			if ($expiration !== false) {
-				$share->setExpirationDate($expiration);
-			}
-		}
-
-		$share->setNodeId((int)$data['file_source']);
-		$share->setNodeType($data['item_type']);
-
-		$share->setProviderId($this->identifier());
-
-		return $share;
-	}
-
-	/**
-	 * Get the node with file $id for $user
-	 *
-	 * @param string $userId
-	 * @param int $id
-	 * @return \OCP\Files\File|\OCP\Files\Folder
-	 * @throws InvalidShare
-	 */
-	private function getNode($userId, $id) {
-		try {
-			$userFolder = $this->rootFolder->getUserFolder($userId);
-		} catch (NoUserException $e) {
-			throw new InvalidShare();
-		}
-
-		$nodes = $userFolder->getById($id);
-
-		if (empty($nodes)) {
-			throw new InvalidShare();
-		}
-
-		return $nodes[0];
-	}
-
-	/**
-	 * A user is deleted from the system
-	 * So clean up the relevant shares.
-	 *
-	 * @param string $uid
-	 * @param int $shareType
-	 */
-	public function userDeleted($uid, $shareType) {
-		$qb = $this->dbConnection->getQueryBuilder();
-
-		$qb->delete('share')
-			->where($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)))
-			->andWhere($qb->expr()->eq('uid_owner', $qb->createNamedParameter($uid)))
-			->execute();
-	}
-
-	/**
-	 * This provider does not support group shares
-	 *
-	 * @param string $gid
-	 */
-	public function groupDeleted($gid) {
-		return;
-	}
-
-	/**
-	 * This provider does not support group shares
-	 *
-	 * @param string $uid
-	 * @param string $gid
-	 */
-	public function userDeletedFromGroup($uid, $gid) {
-		return;
-	}
-
-	/**
-	 * get database row of a give share
-	 *
-	 * @param $id
-	 * @return array
-	 * @throws ShareNotFound
-	 */
-	protected function getRawShare($id) {
-
-		// Now fetch the inserted share and create a complete share object
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('*')
-			->from('share')
-			->where($qb->expr()->eq('id', $qb->createNamedParameter($id)));
-
-		$cursor = $qb->execute();
-		$data = $cursor->fetch();
-		$cursor->closeCursor();
-
-		if ($data === false) {
-			throw new ShareNotFound;
-		}
-
-		return $data;
-	}
-
-	public function getSharesInFolder($userId, Folder $node, $reshares) {
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('*')
-			->from('share', 's')
-			->andWhere($qb->expr()->orX(
-				$qb->expr()->eq('item_type', $qb->createNamedParameter('file')),
-				$qb->expr()->eq('item_type', $qb->createNamedParameter('folder'))
-			))
-			->andWhere(
-				$qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL))
-			);
-
-		/**
-		 * Reshares for this user are shares where they are the owner.
-		 */
-		if ($reshares === false) {
-			$qb->andWhere($qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId)));
-		} else {
-			$qb->andWhere(
-				$qb->expr()->orX(
-					$qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
-					$qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId))
-				)
-			);
-		}
-
-		$qb->innerJoin('s', 'filecache' ,'f', $qb->expr()->eq('s.file_source', 'f.fileid'));
-		$qb->andWhere($qb->expr()->eq('f.parent', $qb->createNamedParameter($node->getId())));
-
-		$qb->orderBy('id');
-
-		$cursor = $qb->execute();
-		$shares = [];
-		while ($data = $cursor->fetch()) {
-			$shares[$data['fileid']][] = $this->createShareObject($data);
-		}
-		$cursor->closeCursor();
-
-		return $shares;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function getAccessList($nodes, $currentAccess) {
-		$ids = [];
-		foreach ($nodes as $node) {
-			$ids[] = $node->getId();
-		}
-
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('share_with')
-			->from('share')
-			->where($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)))
-			->andWhere($qb->expr()->in('file_source', $qb->createNamedParameter($ids, IQueryBuilder::PARAM_INT_ARRAY)))
-			->andWhere($qb->expr()->orX(
-				$qb->expr()->eq('item_type', $qb->createNamedParameter('file')),
-				$qb->expr()->eq('item_type', $qb->createNamedParameter('folder'))
-			))
-			->setMaxResults(1);
-		$cursor = $qb->execute();
-
-		$mail = $cursor->fetch() !== false;
-		$cursor->closeCursor();
-
-		return ['public' => $mail];
-	}
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->update('share')
+            ->where($qb->expr()->eq('id', $qb->createNamedParameter($share->getId())))
+            ->set('permissions', $qb->createNamedParameter($share->getPermissions()))
+            ->set('uid_owner', $qb->createNamedParameter($share->getShareOwner()))
+            ->set('uid_initiator', $qb->createNamedParameter($share->getSharedBy()))
+            ->set('password', $qb->createNamedParameter($share->getPassword()))
+            ->set('expiration', $qb->createNamedParameter($share->getExpirationDate(), IQueryBuilder::PARAM_DATE))
+            ->execute();
+
+        return $share;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function move(IShare $share, $recipient) {
+        /**
+         * nothing to do here, mail shares are only outgoing shares
+         */
+        return $share;
+    }
+
+    /**
+     * Delete a share (owner unShares the file)
+     *
+     * @param IShare $share
+     */
+    public function delete(IShare $share) {
+        $this->removeShareFromTable($share->getId());
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function deleteFromSelf(IShare $share, $recipient) {
+        // nothing to do here, mail shares are only outgoing shares
+        return;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getSharesBy($userId, $shareType, $node, $reshares, $limit, $offset) {
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('*')
+            ->from('share');
+
+        $qb->andWhere($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)));
+
+        /**
+         * Reshares for this user are shares where they are the owner.
+         */
+        if ($reshares === false) {
+            //Special case for old shares created via the web UI
+            $or1 = $qb->expr()->andX(
+                $qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
+                $qb->expr()->isNull('uid_initiator')
+            );
+
+            $qb->andWhere(
+                $qb->expr()->orX(
+                    $qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId)),
+                    $or1
+                )
+            );
+        } else {
+            $qb->andWhere(
+                $qb->expr()->orX(
+                    $qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
+                    $qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId))
+                )
+            );
+        }
+
+        if ($node !== null) {
+            $qb->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($node->getId())));
+        }
+
+        if ($limit !== -1) {
+            $qb->setMaxResults($limit);
+        }
+
+        $qb->setFirstResult($offset);
+        $qb->orderBy('id');
+
+        $cursor = $qb->execute();
+        $shares = [];
+        while($data = $cursor->fetch()) {
+            $shares[] = $this->createShareObject($data);
+        }
+        $cursor->closeCursor();
+
+        return $shares;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getShareById($id, $recipientId = null) {
+        $qb = $this->dbConnection->getQueryBuilder();
+
+        $qb->select('*')
+            ->from('share')
+            ->where($qb->expr()->eq('id', $qb->createNamedParameter($id)))
+            ->andWhere($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)));
+
+        $cursor = $qb->execute();
+        $data = $cursor->fetch();
+        $cursor->closeCursor();
+
+        if ($data === false) {
+            throw new ShareNotFound();
+        }
+
+        try {
+            $share = $this->createShareObject($data);
+        } catch (InvalidShare $e) {
+            throw new ShareNotFound();
+        }
+
+        return $share;
+    }
+
+    /**
+     * Get shares for a given path
+     *
+     * @param \OCP\Files\Node $path
+     * @return IShare[]
+     */
+    public function getSharesByPath(Node $path) {
+        $qb = $this->dbConnection->getQueryBuilder();
+
+        $cursor = $qb->select('*')
+            ->from('share')
+            ->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($path->getId())))
+            ->andWhere($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)))
+            ->execute();
+
+        $shares = [];
+        while($data = $cursor->fetch()) {
+            $shares[] = $this->createShareObject($data);
+        }
+        $cursor->closeCursor();
+
+        return $shares;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getSharedWith($userId, $shareType, $node, $limit, $offset) {
+        /** @var IShare[] $shares */
+        $shares = [];
+
+        //Get shares directly with this user
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('*')
+            ->from('share');
+
+        // Order by id
+        $qb->orderBy('id');
+
+        // Set limit and offset
+        if ($limit !== -1) {
+            $qb->setMaxResults($limit);
+        }
+        $qb->setFirstResult($offset);
+
+        $qb->where($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)));
+        $qb->andWhere($qb->expr()->eq('share_with', $qb->createNamedParameter($userId)));
+
+        // Filter by node if provided
+        if ($node !== null) {
+            $qb->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($node->getId())));
+        }
+
+        $cursor = $qb->execute();
+
+        while($data = $cursor->fetch()) {
+            $shares[] = $this->createShareObject($data);
+        }
+        $cursor->closeCursor();
+
+
+        return $shares;
+    }
+
+    /**
+     * Get a share by token
+     *
+     * @param string $token
+     * @return IShare
+     * @throws ShareNotFound
+     */
+    public function getShareByToken($token) {
+        $qb = $this->dbConnection->getQueryBuilder();
+
+        $cursor = $qb->select('*')
+            ->from('share')
+            ->where($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)))
+            ->andWhere($qb->expr()->eq('token', $qb->createNamedParameter($token)))
+            ->execute();
+
+        $data = $cursor->fetch();
+
+        if ($data === false) {
+            throw new ShareNotFound('Share not found', $this->l->t('Could not find share'));
+        }
+
+        try {
+            $share = $this->createShareObject($data);
+        } catch (InvalidShare $e) {
+            throw new ShareNotFound('Share not found', $this->l->t('Could not find share'));
+        }
+
+        return $share;
+    }
+
+    /**
+     * remove share from table
+     *
+     * @param string $shareId
+     */
+    protected function removeShareFromTable($shareId) {
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->delete('share')
+            ->where($qb->expr()->eq('id', $qb->createNamedParameter($shareId)));
+        $qb->execute();
+    }
+
+    /**
+     * Create a share object from an database row
+     *
+     * @param array $data
+     * @return IShare
+     * @throws InvalidShare
+     * @throws ShareNotFound
+     */
+    protected function createShareObject($data) {
+
+        $share = new Share($this->rootFolder, $this->userManager);
+        $share->setId((int)$data['id'])
+            ->setShareType((int)$data['share_type'])
+            ->setPermissions((int)$data['permissions'])
+            ->setTarget($data['file_target'])
+            ->setMailSend((bool)$data['mail_send'])
+            ->setToken($data['token']);
+
+        $shareTime = new \DateTime();
+        $shareTime->setTimestamp((int)$data['stime']);
+        $share->setShareTime($shareTime);
+        $share->setSharedWith($data['share_with']);
+        $share->setPassword($data['password']);
+
+        if ($data['uid_initiator'] !== null) {
+            $share->setShareOwner($data['uid_owner']);
+            $share->setSharedBy($data['uid_initiator']);
+        } else {
+            //OLD SHARE
+            $share->setSharedBy($data['uid_owner']);
+            $path = $this->getNode($share->getSharedBy(), (int)$data['file_source']);
+
+            $owner = $path->getOwner();
+            $share->setShareOwner($owner->getUID());
+        }
+
+        if ($data['expiration'] !== null) {
+            $expiration = \DateTime::createFromFormat('Y-m-d H:i:s', $data['expiration']);
+            if ($expiration !== false) {
+                $share->setExpirationDate($expiration);
+            }
+        }
+
+        $share->setNodeId((int)$data['file_source']);
+        $share->setNodeType($data['item_type']);
+
+        $share->setProviderId($this->identifier());
+
+        return $share;
+    }
+
+    /**
+     * Get the node with file $id for $user
+     *
+     * @param string $userId
+     * @param int $id
+     * @return \OCP\Files\File|\OCP\Files\Folder
+     * @throws InvalidShare
+     */
+    private function getNode($userId, $id) {
+        try {
+            $userFolder = $this->rootFolder->getUserFolder($userId);
+        } catch (NoUserException $e) {
+            throw new InvalidShare();
+        }
+
+        $nodes = $userFolder->getById($id);
+
+        if (empty($nodes)) {
+            throw new InvalidShare();
+        }
+
+        return $nodes[0];
+    }
+
+    /**
+     * A user is deleted from the system
+     * So clean up the relevant shares.
+     *
+     * @param string $uid
+     * @param int $shareType
+     */
+    public function userDeleted($uid, $shareType) {
+        $qb = $this->dbConnection->getQueryBuilder();
+
+        $qb->delete('share')
+            ->where($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)))
+            ->andWhere($qb->expr()->eq('uid_owner', $qb->createNamedParameter($uid)))
+            ->execute();
+    }
+
+    /**
+     * This provider does not support group shares
+     *
+     * @param string $gid
+     */
+    public function groupDeleted($gid) {
+        return;
+    }
+
+    /**
+     * This provider does not support group shares
+     *
+     * @param string $uid
+     * @param string $gid
+     */
+    public function userDeletedFromGroup($uid, $gid) {
+        return;
+    }
+
+    /**
+     * get database row of a give share
+     *
+     * @param $id
+     * @return array
+     * @throws ShareNotFound
+     */
+    protected function getRawShare($id) {
+
+        // Now fetch the inserted share and create a complete share object
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('*')
+            ->from('share')
+            ->where($qb->expr()->eq('id', $qb->createNamedParameter($id)));
+
+        $cursor = $qb->execute();
+        $data = $cursor->fetch();
+        $cursor->closeCursor();
+
+        if ($data === false) {
+            throw new ShareNotFound;
+        }
+
+        return $data;
+    }
+
+    public function getSharesInFolder($userId, Folder $node, $reshares) {
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('*')
+            ->from('share', 's')
+            ->andWhere($qb->expr()->orX(
+                $qb->expr()->eq('item_type', $qb->createNamedParameter('file')),
+                $qb->expr()->eq('item_type', $qb->createNamedParameter('folder'))
+            ))
+            ->andWhere(
+                $qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL))
+            );
+
+        /**
+         * Reshares for this user are shares where they are the owner.
+         */
+        if ($reshares === false) {
+            $qb->andWhere($qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId)));
+        } else {
+            $qb->andWhere(
+                $qb->expr()->orX(
+                    $qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
+                    $qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId))
+                )
+            );
+        }
+
+        $qb->innerJoin('s', 'filecache' ,'f', $qb->expr()->eq('s.file_source', 'f.fileid'));
+        $qb->andWhere($qb->expr()->eq('f.parent', $qb->createNamedParameter($node->getId())));
+
+        $qb->orderBy('id');
+
+        $cursor = $qb->execute();
+        $shares = [];
+        while ($data = $cursor->fetch()) {
+            $shares[$data['fileid']][] = $this->createShareObject($data);
+        }
+        $cursor->closeCursor();
+
+        return $shares;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getAccessList($nodes, $currentAccess) {
+        $ids = [];
+        foreach ($nodes as $node) {
+            $ids[] = $node->getId();
+        }
+
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('share_with')
+            ->from('share')
+            ->where($qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share::SHARE_TYPE_EMAIL)))
+            ->andWhere($qb->expr()->in('file_source', $qb->createNamedParameter($ids, IQueryBuilder::PARAM_INT_ARRAY)))
+            ->andWhere($qb->expr()->orX(
+                $qb->expr()->eq('item_type', $qb->createNamedParameter('file')),
+                $qb->expr()->eq('item_type', $qb->createNamedParameter('folder'))
+            ))
+            ->setMaxResults(1);
+        $cursor = $qb->execute();
+
+        $mail = $cursor->fetch() !== false;
+        $cursor->closeCursor();
+
+        return ['public' => $mail];
+    }
 
 }

apps/dav/lib/CalDAV/CalDavBackend.php

Indentation +2056 added lines, -2056 removed lines

@@ -62,2061 +62,2061 @@
  */
 class CalDavBackend extends AbstractBackend implements SyncSupport, SubscriptionSupport, SchedulingSupport {
 
-	const PERSONAL_CALENDAR_URI = 'personal';
-	const PERSONAL_CALENDAR_NAME = 'Personal';
-
-	/**
-	 * We need to specify a max date, because we need to stop *somewhere*
-	 *
-	 * On 32 bit system the maximum for a signed integer is 2147483647, so
-	 * MAX_DATE cannot be higher than date('Y-m-d', 2147483647) which results
-	 * in 2038-01-19 to avoid problems when the date is converted
-	 * to a unix timestamp.
-	 */
-	const MAX_DATE = '2038-01-01';
-
-	const ACCESS_PUBLIC = 4;
-	const CLASSIFICATION_PUBLIC = 0;
-	const CLASSIFICATION_PRIVATE = 1;
-	const CLASSIFICATION_CONFIDENTIAL = 2;
-
-	/**
-	 * List of CalDAV properties, and how they map to database field names
-	 * Add your own properties by simply adding on to this array.
-	 *
-	 * Note that only string-based properties are supported here.
-	 *
-	 * @var array
-	 */
-	public $propertyMap = [
-		'{DAV:}displayname'                          => 'displayname',
-		'{urn:ietf:params:xml:ns:caldav}calendar-description' => 'description',
-		'{urn:ietf:params:xml:ns:caldav}calendar-timezone'    => 'timezone',
-		'{http://apple.com/ns/ical/}calendar-order'  => 'calendarorder',
-		'{http://apple.com/ns/ical/}calendar-color'  => 'calendarcolor',
-	];
-
-	/**
-	 * List of subscription properties, and how they map to database field names.
-	 *
-	 * @var array
-	 */
-	public $subscriptionPropertyMap = [
-		'{DAV:}displayname'                                           => 'displayname',
-		'{http://apple.com/ns/ical/}refreshrate'                      => 'refreshrate',
-		'{http://apple.com/ns/ical/}calendar-order'                   => 'calendarorder',
-		'{http://apple.com/ns/ical/}calendar-color'                   => 'calendarcolor',
-		'{http://calendarserver.org/ns/}subscribed-strip-todos'       => 'striptodos',
-		'{http://calendarserver.org/ns/}subscribed-strip-alarms'      => 'stripalarms',
-		'{http://calendarserver.org/ns/}subscribed-strip-attachments' => 'stripattachments',
-	];
-
-	/** @var array properties to index */
-	public static $indexProperties = ['CATEGORIES', 'COMMENT', 'DESCRIPTION',
-		'LOCATION', 'RESOURCES', 'STATUS', 'SUMMARY', 'ATTENDEE', 'CONTACT',
-		'ORGANIZER'];
-
-	/** @var array parameters to index */
-	public static $indexParameters = [
-		'ATTENDEE' => ['CN'],
-		'ORGANIZER' => ['CN'],
-	];
-
-	/**
-	 * @var string[] Map of uid => display name
-	 */
-	protected $userDisplayNames;
-
-	/** @var IDBConnection */
-	private $db;
-
-	/** @var Backend */
-	private $sharingBackend;
-
-	/** @var Principal */
-	private $principalBackend;
-
-	/** @var IUserManager */
-	private $userManager;
-
-	/** @var ISecureRandom */
-	private $random;
-
-	/** @var EventDispatcherInterface */
-	private $dispatcher;
-
-	/** @var bool */
-	private $legacyEndpoint;
-
-	/** @var string */
-	private $dbObjectPropertiesTable = 'calendarobjects_props';
-
-	/**
-	 * CalDavBackend constructor.
-	 *
-	 * @param IDBConnection $db
-	 * @param Principal $principalBackend
-	 * @param IUserManager $userManager
-	 * @param ISecureRandom $random
-	 * @param EventDispatcherInterface $dispatcher
-	 * @param bool $legacyEndpoint
-	 */
-	public function __construct(IDBConnection $db,
-								Principal $principalBackend,
-								IUserManager $userManager,
-								ISecureRandom $random,
-								EventDispatcherInterface $dispatcher,
-								$legacyEndpoint = false) {
-		$this->db = $db;
-		$this->principalBackend = $principalBackend;
-		$this->userManager = $userManager;
-		$this->sharingBackend = new Backend($this->db, $principalBackend, 'calendar');
-		$this->random = $random;
-		$this->dispatcher = $dispatcher;
-		$this->legacyEndpoint = $legacyEndpoint;
-	}
-
-	/**
-	 * Return the number of calendars for a principal
-	 *
-	 * By default this excludes the automatically generated birthday calendar
-	 *
-	 * @param $principalUri
-	 * @param bool $excludeBirthday
-	 * @return int
-	 */
-	public function getCalendarsForUserCount($principalUri, $excludeBirthday = true) {
-		$principalUri = $this->convertPrincipal($principalUri, true);
-		$query = $this->db->getQueryBuilder();
-		$query->select($query->createFunction('COUNT(*)'))
-			->from('calendars')
-			->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)));
-
-		if ($excludeBirthday) {
-			$query->andWhere($query->expr()->neq('uri', $query->createNamedParameter(BirthdayService::BIRTHDAY_CALENDAR_URI)));
-		}
-
-		return (int)$query->execute()->fetchColumn();
-	}
-
-	/**
-	 * Returns a list of calendars for a principal.
-	 *
-	 * Every project is an array with the following keys:
-	 *  * id, a unique id that will be used by other functions to modify the
-	 *    calendar. This can be the same as the uri or a database key.
-	 *  * uri, which the basename of the uri with which the calendar is
-	 *    accessed.
-	 *  * principaluri. The owner of the calendar. Almost always the same as
-	 *    principalUri passed to this method.
-	 *
-	 * Furthermore it can contain webdav properties in clark notation. A very
-	 * common one is '{DAV:}displayname'.
-	 *
-	 * Many clients also require:
-	 * {urn:ietf:params:xml:ns:caldav}supported-calendar-component-set
-	 * For this property, you can just return an instance of
-	 * Sabre\CalDAV\Property\SupportedCalendarComponentSet.
-	 *
-	 * If you return {http://sabredav.org/ns}read-only and set the value to 1,
-	 * ACL will automatically be put in read-only mode.
-	 *
-	 * @param string $principalUri
-	 * @return array
-	 */
-	function getCalendarsForUser($principalUri) {
-		$principalUriOriginal = $principalUri;
-		$principalUri = $this->convertPrincipal($principalUri, true);
-		$fields = array_values($this->propertyMap);
-		$fields[] = 'id';
-		$fields[] = 'uri';
-		$fields[] = 'synctoken';
-		$fields[] = 'components';
-		$fields[] = 'principaluri';
-		$fields[] = 'transparent';
-
-		// Making fields a comma-delimited list
-		$query = $this->db->getQueryBuilder();
-		$query->select($fields)->from('calendars')
-				->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
-				->orderBy('calendarorder', 'ASC');
-		$stmt = $query->execute();
-
-		$calendars = [];
-		while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
-
-			$components = [];
-			if ($row['components']) {
-				$components = explode(',',$row['components']);
-			}
-
-			$calendar = [
-				'id' => $row['id'],
-				'uri' => $row['uri'],
-				'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
-				'{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
-				'{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
-				'{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
-				'{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
-				'{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}owner-principal' => $this->convertPrincipal($principalUri, !$this->legacyEndpoint),
-			];
-
-			foreach($this->propertyMap as $xmlName=>$dbName) {
-				$calendar[$xmlName] = $row[$dbName];
-			}
-
-			$this->addOwnerPrincipal($calendar);
-
-			if (!isset($calendars[$calendar['id']])) {
-				$calendars[$calendar['id']] = $calendar;
-			}
-		}
-
-		$stmt->closeCursor();
-
-		// query for shared calendars
-		$principals = $this->principalBackend->getGroupMembership($principalUriOriginal, true);
-		$principals = array_map(function($principal) {
-			return urldecode($principal);
-		}, $principals);
-		$principals[]= $principalUri;
-
-		$fields = array_values($this->propertyMap);
-		$fields[] = 'a.id';
-		$fields[] = 'a.uri';
-		$fields[] = 'a.synctoken';
-		$fields[] = 'a.components';
-		$fields[] = 'a.principaluri';
-		$fields[] = 'a.transparent';
-		$fields[] = 's.access';
-		$query = $this->db->getQueryBuilder();
-		$result = $query->select($fields)
-			->from('dav_shares', 's')
-			->join('s', 'calendars', 'a', $query->expr()->eq('s.resourceid', 'a.id'))
-			->where($query->expr()->in('s.principaluri', $query->createParameter('principaluri')))
-			->andWhere($query->expr()->eq('s.type', $query->createParameter('type')))
-			->setParameter('type', 'calendar')
-			->setParameter('principaluri', $principals, \Doctrine\DBAL\Connection::PARAM_STR_ARRAY)
-			->execute();
-
-		$readOnlyPropertyName = '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}read-only';
-		while($row = $result->fetch()) {
-			if ($row['principaluri'] === $principalUri) {
-				continue;
-			}
-
-			$readOnly = (int) $row['access'] === Backend::ACCESS_READ;
-			if (isset($calendars[$row['id']])) {
-				if ($readOnly) {
-					// New share can not have more permissions then the old one.
-					continue;
-				}
-				if (isset($calendars[$row['id']][$readOnlyPropertyName]) &&
-					$calendars[$row['id']][$readOnlyPropertyName] === 0) {
-					// Old share is already read-write, no more permissions can be gained
-					continue;
-				}
-			}
-
-			list(, $name) = URLUtil::splitPath($row['principaluri']);
-			$uri = $row['uri'] . '_shared_by_' . $name;
-			$row['displayname'] = $row['displayname'] . ' (' . $this->getUserDisplayName($name) . ')';
-			$components = [];
-			if ($row['components']) {
-				$components = explode(',',$row['components']);
-			}
-			$calendar = [
-				'id' => $row['id'],
-				'uri' => $uri,
-				'principaluri' => $this->convertPrincipal($principalUri, !$this->legacyEndpoint),
-				'{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
-				'{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
-				'{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
-				'{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
-				'{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}owner-principal' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
-				$readOnlyPropertyName => $readOnly,
-			];
-
-			foreach($this->propertyMap as $xmlName=>$dbName) {
-				$calendar[$xmlName] = $row[$dbName];
-			}
-
-			$this->addOwnerPrincipal($calendar);
-
-			$calendars[$calendar['id']] = $calendar;
-		}
-		$result->closeCursor();
-
-		return array_values($calendars);
-	}
-
-	public function getUsersOwnCalendars($principalUri) {
-		$principalUri = $this->convertPrincipal($principalUri, true);
-		$fields = array_values($this->propertyMap);
-		$fields[] = 'id';
-		$fields[] = 'uri';
-		$fields[] = 'synctoken';
-		$fields[] = 'components';
-		$fields[] = 'principaluri';
-		$fields[] = 'transparent';
-		// Making fields a comma-delimited list
-		$query = $this->db->getQueryBuilder();
-		$query->select($fields)->from('calendars')
-			->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
-			->orderBy('calendarorder', 'ASC');
-		$stmt = $query->execute();
-		$calendars = [];
-		while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
-			$components = [];
-			if ($row['components']) {
-				$components = explode(',',$row['components']);
-			}
-			$calendar = [
-				'id' => $row['id'],
-				'uri' => $row['uri'],
-				'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
-				'{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
-				'{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
-				'{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
-				'{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
-			];
-			foreach($this->propertyMap as $xmlName=>$dbName) {
-				$calendar[$xmlName] = $row[$dbName];
-			}
-
-			$this->addOwnerPrincipal($calendar);
-
-			if (!isset($calendars[$calendar['id']])) {
-				$calendars[$calendar['id']] = $calendar;
-			}
-		}
-		$stmt->closeCursor();
-		return array_values($calendars);
-	}
-
-
-	private function getUserDisplayName($uid) {
-		if (!isset($this->userDisplayNames[$uid])) {
-			$user = $this->userManager->get($uid);
-
-			if ($user instanceof IUser) {
-				$this->userDisplayNames[$uid] = $user->getDisplayName();
-			} else {
-				$this->userDisplayNames[$uid] = $uid;
-			}
-		}
-
-		return $this->userDisplayNames[$uid];
-	}
+    const PERSONAL_CALENDAR_URI = 'personal';
+    const PERSONAL_CALENDAR_NAME = 'Personal';
+
+    /**
+     * We need to specify a max date, because we need to stop *somewhere*
+     *
+     * On 32 bit system the maximum for a signed integer is 2147483647, so
+     * MAX_DATE cannot be higher than date('Y-m-d', 2147483647) which results
+     * in 2038-01-19 to avoid problems when the date is converted
+     * to a unix timestamp.
+     */
+    const MAX_DATE = '2038-01-01';
+
+    const ACCESS_PUBLIC = 4;
+    const CLASSIFICATION_PUBLIC = 0;
+    const CLASSIFICATION_PRIVATE = 1;
+    const CLASSIFICATION_CONFIDENTIAL = 2;
+
+    /**
+     * List of CalDAV properties, and how they map to database field names
+     * Add your own properties by simply adding on to this array.
+     *
+     * Note that only string-based properties are supported here.
+     *
+     * @var array
+     */
+    public $propertyMap = [
+        '{DAV:}displayname'                          => 'displayname',
+        '{urn:ietf:params:xml:ns:caldav}calendar-description' => 'description',
+        '{urn:ietf:params:xml:ns:caldav}calendar-timezone'    => 'timezone',
+        '{http://apple.com/ns/ical/}calendar-order'  => 'calendarorder',
+        '{http://apple.com/ns/ical/}calendar-color'  => 'calendarcolor',
+    ];
+
+    /**
+     * List of subscription properties, and how they map to database field names.
+     *
+     * @var array
+     */
+    public $subscriptionPropertyMap = [
+        '{DAV:}displayname'                                           => 'displayname',
+        '{http://apple.com/ns/ical/}refreshrate'                      => 'refreshrate',
+        '{http://apple.com/ns/ical/}calendar-order'                   => 'calendarorder',
+        '{http://apple.com/ns/ical/}calendar-color'                   => 'calendarcolor',
+        '{http://calendarserver.org/ns/}subscribed-strip-todos'       => 'striptodos',
+        '{http://calendarserver.org/ns/}subscribed-strip-alarms'      => 'stripalarms',
+        '{http://calendarserver.org/ns/}subscribed-strip-attachments' => 'stripattachments',
+    ];
+
+    /** @var array properties to index */
+    public static $indexProperties = ['CATEGORIES', 'COMMENT', 'DESCRIPTION',
+        'LOCATION', 'RESOURCES', 'STATUS', 'SUMMARY', 'ATTENDEE', 'CONTACT',
+        'ORGANIZER'];
+
+    /** @var array parameters to index */
+    public static $indexParameters = [
+        'ATTENDEE' => ['CN'],
+        'ORGANIZER' => ['CN'],
+    ];
+
+    /**
+     * @var string[] Map of uid => display name
+     */
+    protected $userDisplayNames;
+
+    /** @var IDBConnection */
+    private $db;
+
+    /** @var Backend */
+    private $sharingBackend;
+
+    /** @var Principal */
+    private $principalBackend;
+
+    /** @var IUserManager */
+    private $userManager;
+
+    /** @var ISecureRandom */
+    private $random;
+
+    /** @var EventDispatcherInterface */
+    private $dispatcher;
+
+    /** @var bool */
+    private $legacyEndpoint;
+
+    /** @var string */
+    private $dbObjectPropertiesTable = 'calendarobjects_props';
+
+    /**
+     * CalDavBackend constructor.
+     *
+     * @param IDBConnection $db
+     * @param Principal $principalBackend
+     * @param IUserManager $userManager
+     * @param ISecureRandom $random
+     * @param EventDispatcherInterface $dispatcher
+     * @param bool $legacyEndpoint
+     */
+    public function __construct(IDBConnection $db,
+                                Principal $principalBackend,
+                                IUserManager $userManager,
+                                ISecureRandom $random,
+                                EventDispatcherInterface $dispatcher,
+                                $legacyEndpoint = false) {
+        $this->db = $db;
+        $this->principalBackend = $principalBackend;
+        $this->userManager = $userManager;
+        $this->sharingBackend = new Backend($this->db, $principalBackend, 'calendar');
+        $this->random = $random;
+        $this->dispatcher = $dispatcher;
+        $this->legacyEndpoint = $legacyEndpoint;
+    }
+
+    /**
+     * Return the number of calendars for a principal
+     *
+     * By default this excludes the automatically generated birthday calendar
+     *
+     * @param $principalUri
+     * @param bool $excludeBirthday
+     * @return int
+     */
+    public function getCalendarsForUserCount($principalUri, $excludeBirthday = true) {
+        $principalUri = $this->convertPrincipal($principalUri, true);
+        $query = $this->db->getQueryBuilder();
+        $query->select($query->createFunction('COUNT(*)'))
+            ->from('calendars')
+            ->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)));
+
+        if ($excludeBirthday) {
+            $query->andWhere($query->expr()->neq('uri', $query->createNamedParameter(BirthdayService::BIRTHDAY_CALENDAR_URI)));
+        }
+
+        return (int)$query->execute()->fetchColumn();
+    }
+
+    /**
+     * Returns a list of calendars for a principal.
+     *
+     * Every project is an array with the following keys:
+     *  * id, a unique id that will be used by other functions to modify the
+     *    calendar. This can be the same as the uri or a database key.
+     *  * uri, which the basename of the uri with which the calendar is
+     *    accessed.
+     *  * principaluri. The owner of the calendar. Almost always the same as
+     *    principalUri passed to this method.
+     *
+     * Furthermore it can contain webdav properties in clark notation. A very
+     * common one is '{DAV:}displayname'.
+     *
+     * Many clients also require:
+     * {urn:ietf:params:xml:ns:caldav}supported-calendar-component-set
+     * For this property, you can just return an instance of
+     * Sabre\CalDAV\Property\SupportedCalendarComponentSet.
+     *
+     * If you return {http://sabredav.org/ns}read-only and set the value to 1,
+     * ACL will automatically be put in read-only mode.
+     *
+     * @param string $principalUri
+     * @return array
+     */
+    function getCalendarsForUser($principalUri) {
+        $principalUriOriginal = $principalUri;
+        $principalUri = $this->convertPrincipal($principalUri, true);
+        $fields = array_values($this->propertyMap);
+        $fields[] = 'id';
+        $fields[] = 'uri';
+        $fields[] = 'synctoken';
+        $fields[] = 'components';
+        $fields[] = 'principaluri';
+        $fields[] = 'transparent';
+
+        // Making fields a comma-delimited list
+        $query = $this->db->getQueryBuilder();
+        $query->select($fields)->from('calendars')
+                ->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
+                ->orderBy('calendarorder', 'ASC');
+        $stmt = $query->execute();
+
+        $calendars = [];
+        while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+
+            $components = [];
+            if ($row['components']) {
+                $components = explode(',',$row['components']);
+            }
+
+            $calendar = [
+                'id' => $row['id'],
+                'uri' => $row['uri'],
+                'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
+                '{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
+                '{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
+                '{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
+                '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
+                '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}owner-principal' => $this->convertPrincipal($principalUri, !$this->legacyEndpoint),
+            ];
+
+            foreach($this->propertyMap as $xmlName=>$dbName) {
+                $calendar[$xmlName] = $row[$dbName];
+            }
+
+            $this->addOwnerPrincipal($calendar);
+
+            if (!isset($calendars[$calendar['id']])) {
+                $calendars[$calendar['id']] = $calendar;
+            }
+        }
+
+        $stmt->closeCursor();
+
+        // query for shared calendars
+        $principals = $this->principalBackend->getGroupMembership($principalUriOriginal, true);
+        $principals = array_map(function($principal) {
+            return urldecode($principal);
+        }, $principals);
+        $principals[]= $principalUri;
+
+        $fields = array_values($this->propertyMap);
+        $fields[] = 'a.id';
+        $fields[] = 'a.uri';
+        $fields[] = 'a.synctoken';
+        $fields[] = 'a.components';
+        $fields[] = 'a.principaluri';
+        $fields[] = 'a.transparent';
+        $fields[] = 's.access';
+        $query = $this->db->getQueryBuilder();
+        $result = $query->select($fields)
+            ->from('dav_shares', 's')
+            ->join('s', 'calendars', 'a', $query->expr()->eq('s.resourceid', 'a.id'))
+            ->where($query->expr()->in('s.principaluri', $query->createParameter('principaluri')))
+            ->andWhere($query->expr()->eq('s.type', $query->createParameter('type')))
+            ->setParameter('type', 'calendar')
+            ->setParameter('principaluri', $principals, \Doctrine\DBAL\Connection::PARAM_STR_ARRAY)
+            ->execute();
+
+        $readOnlyPropertyName = '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}read-only';
+        while($row = $result->fetch()) {
+            if ($row['principaluri'] === $principalUri) {
+                continue;
+            }
+
+            $readOnly = (int) $row['access'] === Backend::ACCESS_READ;
+            if (isset($calendars[$row['id']])) {
+                if ($readOnly) {
+                    // New share can not have more permissions then the old one.
+                    continue;
+                }
+                if (isset($calendars[$row['id']][$readOnlyPropertyName]) &&
+                    $calendars[$row['id']][$readOnlyPropertyName] === 0) {
+                    // Old share is already read-write, no more permissions can be gained
+                    continue;
+                }
+            }
+
+            list(, $name) = URLUtil::splitPath($row['principaluri']);
+            $uri = $row['uri'] . '_shared_by_' . $name;
+            $row['displayname'] = $row['displayname'] . ' (' . $this->getUserDisplayName($name) . ')';
+            $components = [];
+            if ($row['components']) {
+                $components = explode(',',$row['components']);
+            }
+            $calendar = [
+                'id' => $row['id'],
+                'uri' => $uri,
+                'principaluri' => $this->convertPrincipal($principalUri, !$this->legacyEndpoint),
+                '{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
+                '{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
+                '{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
+                '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
+                '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}owner-principal' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
+                $readOnlyPropertyName => $readOnly,
+            ];
+
+            foreach($this->propertyMap as $xmlName=>$dbName) {
+                $calendar[$xmlName] = $row[$dbName];
+            }
+
+            $this->addOwnerPrincipal($calendar);
+
+            $calendars[$calendar['id']] = $calendar;
+        }
+        $result->closeCursor();
+
+        return array_values($calendars);
+    }
+
+    public function getUsersOwnCalendars($principalUri) {
+        $principalUri = $this->convertPrincipal($principalUri, true);
+        $fields = array_values($this->propertyMap);
+        $fields[] = 'id';
+        $fields[] = 'uri';
+        $fields[] = 'synctoken';
+        $fields[] = 'components';
+        $fields[] = 'principaluri';
+        $fields[] = 'transparent';
+        // Making fields a comma-delimited list
+        $query = $this->db->getQueryBuilder();
+        $query->select($fields)->from('calendars')
+            ->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
+            ->orderBy('calendarorder', 'ASC');
+        $stmt = $query->execute();
+        $calendars = [];
+        while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+            $components = [];
+            if ($row['components']) {
+                $components = explode(',',$row['components']);
+            }
+            $calendar = [
+                'id' => $row['id'],
+                'uri' => $row['uri'],
+                'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
+                '{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
+                '{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
+                '{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
+                '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
+            ];
+            foreach($this->propertyMap as $xmlName=>$dbName) {
+                $calendar[$xmlName] = $row[$dbName];
+            }
+
+            $this->addOwnerPrincipal($calendar);
+
+            if (!isset($calendars[$calendar['id']])) {
+                $calendars[$calendar['id']] = $calendar;
+            }
+        }
+        $stmt->closeCursor();
+        return array_values($calendars);
+    }
+
+
+    private function getUserDisplayName($uid) {
+        if (!isset($this->userDisplayNames[$uid])) {
+            $user = $this->userManager->get($uid);
+
+            if ($user instanceof IUser) {
+                $this->userDisplayNames[$uid] = $user->getDisplayName();
+            } else {
+                $this->userDisplayNames[$uid] = $uid;
+            }
+        }
+
+        return $this->userDisplayNames[$uid];
+    }
 	
-	/**
-	 * @return array
-	 */
-	public function getPublicCalendars() {
-		$fields = array_values($this->propertyMap);
-		$fields[] = 'a.id';
-		$fields[] = 'a.uri';
-		$fields[] = 'a.synctoken';
-		$fields[] = 'a.components';
-		$fields[] = 'a.principaluri';
-		$fields[] = 'a.transparent';
-		$fields[] = 's.access';
-		$fields[] = 's.publicuri';
-		$calendars = [];
-		$query = $this->db->getQueryBuilder();
-		$result = $query->select($fields)
-			->from('dav_shares', 's')
-			->join('s', 'calendars', 'a', $query->expr()->eq('s.resourceid', 'a.id'))
-			->where($query->expr()->in('s.access', $query->createNamedParameter(self::ACCESS_PUBLIC)))
-			->andWhere($query->expr()->eq('s.type', $query->createNamedParameter('calendar')))
-			->execute();
-
-		while($row = $result->fetch()) {
-			list(, $name) = URLUtil::splitPath($row['principaluri']);
-			$row['displayname'] = $row['displayname'] . "($name)";
-			$components = [];
-			if ($row['components']) {
-				$components = explode(',',$row['components']);
-			}
-			$calendar = [
-				'id' => $row['id'],
-				'uri' => $row['publicuri'],
-				'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
-				'{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
-				'{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
-				'{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
-				'{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
-				'{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}owner-principal' => $this->convertPrincipal($row['principaluri'], $this->legacyEndpoint),
-				'{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}read-only' => (int)$row['access'] === Backend::ACCESS_READ,
-				'{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}public' => (int)$row['access'] === self::ACCESS_PUBLIC,
-			];
-
-			foreach($this->propertyMap as $xmlName=>$dbName) {
-				$calendar[$xmlName] = $row[$dbName];
-			}
-
-			$this->addOwnerPrincipal($calendar);
-
-			if (!isset($calendars[$calendar['id']])) {
-				$calendars[$calendar['id']] = $calendar;
-			}
-		}
-		$result->closeCursor();
-
-		return array_values($calendars);
-	}
-
-	/**
-	 * @param string $uri
-	 * @return array
-	 * @throws NotFound
-	 */
-	public function getPublicCalendar($uri) {
-		$fields = array_values($this->propertyMap);
-		$fields[] = 'a.id';
-		$fields[] = 'a.uri';
-		$fields[] = 'a.synctoken';
-		$fields[] = 'a.components';
-		$fields[] = 'a.principaluri';
-		$fields[] = 'a.transparent';
-		$fields[] = 's.access';
-		$fields[] = 's.publicuri';
-		$query = $this->db->getQueryBuilder();
-		$result = $query->select($fields)
-			->from('dav_shares', 's')
-			->join('s', 'calendars', 'a', $query->expr()->eq('s.resourceid', 'a.id'))
-			->where($query->expr()->in('s.access', $query->createNamedParameter(self::ACCESS_PUBLIC)))
-			->andWhere($query->expr()->eq('s.type', $query->createNamedParameter('calendar')))
-			->andWhere($query->expr()->eq('s.publicuri', $query->createNamedParameter($uri)))
-			->execute();
-
-		$row = $result->fetch(\PDO::FETCH_ASSOC);
-
-		$result->closeCursor();
-
-		if ($row === false) {
-			throw new NotFound('Node with name \'' . $uri . '\' could not be found');
-		}
-
-		list(, $name) = URLUtil::splitPath($row['principaluri']);
-		$row['displayname'] = $row['displayname'] . ' ' . "($name)";
-		$components = [];
-		if ($row['components']) {
-			$components = explode(',',$row['components']);
-		}
-		$calendar = [
-			'id' => $row['id'],
-			'uri' => $row['publicuri'],
-			'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
-			'{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
-			'{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
-			'{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
-			'{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
-			'{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}owner-principal' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
-			'{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}read-only' => (int)$row['access'] === Backend::ACCESS_READ,
-			'{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}public' => (int)$row['access'] === self::ACCESS_PUBLIC,
-		];
-
-		foreach($this->propertyMap as $xmlName=>$dbName) {
-			$calendar[$xmlName] = $row[$dbName];
-		}
-
-		$this->addOwnerPrincipal($calendar);
-
-		return $calendar;
-
-	}
-
-	/**
-	 * @param string $principal
-	 * @param string $uri
-	 * @return array|null
-	 */
-	public function getCalendarByUri($principal, $uri) {
-		$fields = array_values($this->propertyMap);
-		$fields[] = 'id';
-		$fields[] = 'uri';
-		$fields[] = 'synctoken';
-		$fields[] = 'components';
-		$fields[] = 'principaluri';
-		$fields[] = 'transparent';
-
-		// Making fields a comma-delimited list
-		$query = $this->db->getQueryBuilder();
-		$query->select($fields)->from('calendars')
-			->where($query->expr()->eq('uri', $query->createNamedParameter($uri)))
-			->andWhere($query->expr()->eq('principaluri', $query->createNamedParameter($principal)))
-			->setMaxResults(1);
-		$stmt = $query->execute();
-
-		$row = $stmt->fetch(\PDO::FETCH_ASSOC);
-		$stmt->closeCursor();
-		if ($row === false) {
-			return null;
-		}
-
-		$components = [];
-		if ($row['components']) {
-			$components = explode(',',$row['components']);
-		}
-
-		$calendar = [
-			'id' => $row['id'],
-			'uri' => $row['uri'],
-			'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
-			'{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
-			'{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
-			'{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
-			'{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
-		];
-
-		foreach($this->propertyMap as $xmlName=>$dbName) {
-			$calendar[$xmlName] = $row[$dbName];
-		}
-
-		$this->addOwnerPrincipal($calendar);
-
-		return $calendar;
-	}
-
-	public function getCalendarById($calendarId) {
-		$fields = array_values($this->propertyMap);
-		$fields[] = 'id';
-		$fields[] = 'uri';
-		$fields[] = 'synctoken';
-		$fields[] = 'components';
-		$fields[] = 'principaluri';
-		$fields[] = 'transparent';
-
-		// Making fields a comma-delimited list
-		$query = $this->db->getQueryBuilder();
-		$query->select($fields)->from('calendars')
-			->where($query->expr()->eq('id', $query->createNamedParameter($calendarId)))
-			->setMaxResults(1);
-		$stmt = $query->execute();
-
-		$row = $stmt->fetch(\PDO::FETCH_ASSOC);
-		$stmt->closeCursor();
-		if ($row === false) {
-			return null;
-		}
-
-		$components = [];
-		if ($row['components']) {
-			$components = explode(',',$row['components']);
-		}
-
-		$calendar = [
-			'id' => $row['id'],
-			'uri' => $row['uri'],
-			'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
-			'{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
-			'{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
-			'{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
-			'{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
-		];
-
-		foreach($this->propertyMap as $xmlName=>$dbName) {
-			$calendar[$xmlName] = $row[$dbName];
-		}
-
-		$this->addOwnerPrincipal($calendar);
-
-		return $calendar;
-	}
-
-	/**
-	 * Creates a new calendar for a principal.
-	 *
-	 * If the creation was a success, an id must be returned that can be used to reference
-	 * this calendar in other methods, such as updateCalendar.
-	 *
-	 * @param string $principalUri
-	 * @param string $calendarUri
-	 * @param array $properties
-	 * @return int
-	 */
-	function createCalendar($principalUri, $calendarUri, array $properties) {
-		$values = [
-			'principaluri' => $this->convertPrincipal($principalUri, true),
-			'uri'          => $calendarUri,
-			'synctoken'    => 1,
-			'transparent'  => 0,
-			'components'   => 'VEVENT,VTODO',
-			'displayname'  => $calendarUri
-		];
-
-		// Default value
-		$sccs = '{urn:ietf:params:xml:ns:caldav}supported-calendar-component-set';
-		if (isset($properties[$sccs])) {
-			if (!($properties[$sccs] instanceof SupportedCalendarComponentSet)) {
-				throw new DAV\Exception('The ' . $sccs . ' property must be of type: \Sabre\CalDAV\Property\SupportedCalendarComponentSet');
-			}
-			$values['components'] = implode(',',$properties[$sccs]->getValue());
-		}
-		$transp = '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp';
-		if (isset($properties[$transp])) {
-			$values['transparent'] = (int) ($properties[$transp]->getValue() === 'transparent');
-		}
-
-		foreach($this->propertyMap as $xmlName=>$dbName) {
-			if (isset($properties[$xmlName])) {
-				$values[$dbName] = $properties[$xmlName];
-			}
-		}
-
-		$query = $this->db->getQueryBuilder();
-		$query->insert('calendars');
-		foreach($values as $column => $value) {
-			$query->setValue($column, $query->createNamedParameter($value));
-		}
-		$query->execute();
-		$calendarId = $query->getLastInsertId();
-
-		$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::createCalendar', new GenericEvent(
-			'\OCA\DAV\CalDAV\CalDavBackend::createCalendar',
-			[
-				'calendarId' => $calendarId,
-				'calendarData' => $this->getCalendarById($calendarId),
-		]));
-
-		return $calendarId;
-	}
-
-	/**
-	 * Updates properties for a calendar.
-	 *
-	 * The list of mutations is stored in a Sabre\DAV\PropPatch object.
-	 * To do the actual updates, you must tell this object which properties
-	 * you're going to process with the handle() method.
-	 *
-	 * Calling the handle method is like telling the PropPatch object "I
-	 * promise I can handle updating this property".
-	 *
-	 * Read the PropPatch documentation for more info and examples.
-	 *
-	 * @param PropPatch $propPatch
-	 * @return void
-	 */
-	function updateCalendar($calendarId, PropPatch $propPatch) {
-		$supportedProperties = array_keys($this->propertyMap);
-		$supportedProperties[] = '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp';
-
-		$propPatch->handle($supportedProperties, function($mutations) use ($calendarId) {
-			$newValues = [];
-			foreach ($mutations as $propertyName => $propertyValue) {
-
-				switch ($propertyName) {
-					case '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' :
-						$fieldName = 'transparent';
-						$newValues[$fieldName] = (int) ($propertyValue->getValue() === 'transparent');
-						break;
-					default :
-						$fieldName = $this->propertyMap[$propertyName];
-						$newValues[$fieldName] = $propertyValue;
-						break;
-				}
-
-			}
-			$query = $this->db->getQueryBuilder();
-			$query->update('calendars');
-			foreach ($newValues as $fieldName => $value) {
-				$query->set($fieldName, $query->createNamedParameter($value));
-			}
-			$query->where($query->expr()->eq('id', $query->createNamedParameter($calendarId)));
-			$query->execute();
-
-			$this->addChange($calendarId, "", 2);
-
-			$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::updateCalendar', new GenericEvent(
-				'\OCA\DAV\CalDAV\CalDavBackend::updateCalendar',
-				[
-					'calendarId' => $calendarId,
-					'calendarData' => $this->getCalendarById($calendarId),
-					'shares' => $this->getShares($calendarId),
-					'propertyMutations' => $mutations,
-			]));
-
-			return true;
-		});
-	}
-
-	/**
-	 * Delete a calendar and all it's objects
-	 *
-	 * @param mixed $calendarId
-	 * @return void
-	 */
-	function deleteCalendar($calendarId) {
-		$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::deleteCalendar', new GenericEvent(
-			'\OCA\DAV\CalDAV\CalDavBackend::deleteCalendar',
-			[
-				'calendarId' => $calendarId,
-				'calendarData' => $this->getCalendarById($calendarId),
-				'shares' => $this->getShares($calendarId),
-		]));
-
-		$stmt = $this->db->prepare('DELETE FROM `*PREFIX*calendarobjects` WHERE `calendarid` = ?');
-		$stmt->execute([$calendarId]);
-
-		$stmt = $this->db->prepare('DELETE FROM `*PREFIX*calendars` WHERE `id` = ?');
-		$stmt->execute([$calendarId]);
-
-		$stmt = $this->db->prepare('DELETE FROM `*PREFIX*calendarchanges` WHERE `calendarid` = ?');
-		$stmt->execute([$calendarId]);
-
-		$this->sharingBackend->deleteAllShares($calendarId);
-
-		$query = $this->db->getQueryBuilder();
-		$query->delete($this->dbObjectPropertiesTable)
-			->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)))
-			->execute();
-	}
-
-	/**
-	 * Delete all of an user's shares
-	 *
-	 * @param string $principaluri
-	 * @return void
-	 */
-	function deleteAllSharesByUser($principaluri) {
-		$this->sharingBackend->deleteAllSharesByUser($principaluri);
-	}
-
-	/**
-	 * Returns all calendar objects within a calendar.
-	 *
-	 * Every item contains an array with the following keys:
-	 *   * calendardata - The iCalendar-compatible calendar data
-	 *   * uri - a unique key which will be used to construct the uri. This can
-	 *     be any arbitrary string, but making sure it ends with '.ics' is a
-	 *     good idea. This is only the basename, or filename, not the full
-	 *     path.
-	 *   * lastmodified - a timestamp of the last modification time
-	 *   * etag - An arbitrary string, surrounded by double-quotes. (e.g.:
-	 *   '"abcdef"')
-	 *   * size - The size of the calendar objects, in bytes.
-	 *   * component - optional, a string containing the type of object, such
-	 *     as 'vevent' or 'vtodo'. If specified, this will be used to populate
-	 *     the Content-Type header.
-	 *
-	 * Note that the etag is optional, but it's highly encouraged to return for
-	 * speed reasons.
-	 *
-	 * The calendardata is also optional. If it's not returned
-	 * 'getCalendarObject' will be called later, which *is* expected to return
-	 * calendardata.
-	 *
-	 * If neither etag or size are specified, the calendardata will be
-	 * used/fetched to determine these numbers. If both are specified the
-	 * amount of times this is needed is reduced by a great degree.
-	 *
-	 * @param mixed $calendarId
-	 * @return array
-	 */
-	function getCalendarObjects($calendarId) {
-		$query = $this->db->getQueryBuilder();
-		$query->select(['id', 'uri', 'lastmodified', 'etag', 'calendarid', 'size', 'componenttype', 'classification'])
-			->from('calendarobjects')
-			->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)));
-		$stmt = $query->execute();
-
-		$result = [];
-		foreach($stmt->fetchAll(\PDO::FETCH_ASSOC) as $row) {
-			$result[] = [
-					'id'           => $row['id'],
-					'uri'          => $row['uri'],
-					'lastmodified' => $row['lastmodified'],
-					'etag'         => '"' . $row['etag'] . '"',
-					'calendarid'   => $row['calendarid'],
-					'size'         => (int)$row['size'],
-					'component'    => strtolower($row['componenttype']),
-					'classification'=> (int)$row['classification']
-			];
-		}
-
-		return $result;
-	}
-
-	/**
-	 * Returns information from a single calendar object, based on it's object
-	 * uri.
-	 *
-	 * The object uri is only the basename, or filename and not a full path.
-	 *
-	 * The returned array must have the same keys as getCalendarObjects. The
-	 * 'calendardata' object is required here though, while it's not required
-	 * for getCalendarObjects.
-	 *
-	 * This method must return null if the object did not exist.
-	 *
-	 * @param mixed $calendarId
-	 * @param string $objectUri
-	 * @return array|null
-	 */
-	function getCalendarObject($calendarId, $objectUri) {
-
-		$query = $this->db->getQueryBuilder();
-		$query->select(['id', 'uri', 'lastmodified', 'etag', 'calendarid', 'size', 'calendardata', 'componenttype', 'classification'])
-				->from('calendarobjects')
-				->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)))
-				->andWhere($query->expr()->eq('uri', $query->createNamedParameter($objectUri)));
-		$stmt = $query->execute();
-		$row = $stmt->fetch(\PDO::FETCH_ASSOC);
-
-		if(!$row) return null;
-
-		return [
-				'id'            => $row['id'],
-				'uri'           => $row['uri'],
-				'lastmodified'  => $row['lastmodified'],
-				'etag'          => '"' . $row['etag'] . '"',
-				'calendarid'    => $row['calendarid'],
-				'size'          => (int)$row['size'],
-				'calendardata'  => $this->readBlob($row['calendardata']),
-				'component'     => strtolower($row['componenttype']),
-				'classification'=> (int)$row['classification']
-		];
-	}
-
-	/**
-	 * Returns a list of calendar objects.
-	 *
-	 * This method should work identical to getCalendarObject, but instead
-	 * return all the calendar objects in the list as an array.
-	 *
-	 * If the backend supports this, it may allow for some speed-ups.
-	 *
-	 * @param mixed $calendarId
-	 * @param string[] $uris
-	 * @return array
-	 */
-	function getMultipleCalendarObjects($calendarId, array $uris) {
-		if (empty($uris)) {
-			return [];
-		}
-
-		$chunks = array_chunk($uris, 100);
-		$objects = [];
-
-		$query = $this->db->getQueryBuilder();
-		$query->select(['id', 'uri', 'lastmodified', 'etag', 'calendarid', 'size', 'calendardata', 'componenttype', 'classification'])
-			->from('calendarobjects')
-			->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)))
-			->andWhere($query->expr()->in('uri', $query->createParameter('uri')));
-
-		foreach ($chunks as $uris) {
-			$query->setParameter('uri', $uris, IQueryBuilder::PARAM_STR_ARRAY);
-			$result = $query->execute();
-
-			while ($row = $result->fetch()) {
-				$objects[] = [
-					'id'           => $row['id'],
-					'uri'          => $row['uri'],
-					'lastmodified' => $row['lastmodified'],
-					'etag'         => '"' . $row['etag'] . '"',
-					'calendarid'   => $row['calendarid'],
-					'size'         => (int)$row['size'],
-					'calendardata' => $this->readBlob($row['calendardata']),
-					'component'    => strtolower($row['componenttype']),
-					'classification' => (int)$row['classification']
-				];
-			}
-			$result->closeCursor();
-		}
-		return $objects;
-	}
-
-	/**
-	 * Creates a new calendar object.
-	 *
-	 * The object uri is only the basename, or filename and not a full path.
-	 *
-	 * It is possible return an etag from this function, which will be used in
-	 * the response to this PUT request. Note that the ETag must be surrounded
-	 * by double-quotes.
-	 *
-	 * However, you should only really return this ETag if you don't mangle the
-	 * calendar-data. If the result of a subsequent GET to this object is not
-	 * the exact same as this request body, you should omit the ETag.
-	 *
-	 * @param mixed $calendarId
-	 * @param string $objectUri
-	 * @param string $calendarData
-	 * @return string
-	 */
-	function createCalendarObject($calendarId, $objectUri, $calendarData) {
-		$extraData = $this->getDenormalizedData($calendarData);
-
-		$query = $this->db->getQueryBuilder();
-		$query->insert('calendarobjects')
-			->values([
-				'calendarid' => $query->createNamedParameter($calendarId),
-				'uri' => $query->createNamedParameter($objectUri),
-				'calendardata' => $query->createNamedParameter($calendarData, IQueryBuilder::PARAM_LOB),
-				'lastmodified' => $query->createNamedParameter(time()),
-				'etag' => $query->createNamedParameter($extraData['etag']),
-				'size' => $query->createNamedParameter($extraData['size']),
-				'componenttype' => $query->createNamedParameter($extraData['componentType']),
-				'firstoccurence' => $query->createNamedParameter($extraData['firstOccurence']),
-				'lastoccurence' => $query->createNamedParameter($extraData['lastOccurence']),
-				'classification' => $query->createNamedParameter($extraData['classification']),
-				'uid' => $query->createNamedParameter($extraData['uid']),
-			])
-			->execute();
-
-		$this->updateProperties($calendarId, $objectUri, $calendarData);
-
-		$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::createCalendarObject', new GenericEvent(
-			'\OCA\DAV\CalDAV\CalDavBackend::createCalendarObject',
-			[
-				'calendarId' => $calendarId,
-				'calendarData' => $this->getCalendarById($calendarId),
-				'shares' => $this->getShares($calendarId),
-				'objectData' => $this->getCalendarObject($calendarId, $objectUri),
-			]
-		));
-		$this->addChange($calendarId, $objectUri, 1);
-
-		return '"' . $extraData['etag'] . '"';
-	}
-
-	/**
-	 * Updates an existing calendarobject, based on it's uri.
-	 *
-	 * The object uri is only the basename, or filename and not a full path.
-	 *
-	 * It is possible return an etag from this function, which will be used in
-	 * the response to this PUT request. Note that the ETag must be surrounded
-	 * by double-quotes.
-	 *
-	 * However, you should only really return this ETag if you don't mangle the
-	 * calendar-data. If the result of a subsequent GET to this object is not
-	 * the exact same as this request body, you should omit the ETag.
-	 *
-	 * @param mixed $calendarId
-	 * @param string $objectUri
-	 * @param string $calendarData
-	 * @return string
-	 */
-	function updateCalendarObject($calendarId, $objectUri, $calendarData) {
-		$extraData = $this->getDenormalizedData($calendarData);
-
-		$query = $this->db->getQueryBuilder();
-		$query->update('calendarobjects')
-				->set('calendardata', $query->createNamedParameter($calendarData, IQueryBuilder::PARAM_LOB))
-				->set('lastmodified', $query->createNamedParameter(time()))
-				->set('etag', $query->createNamedParameter($extraData['etag']))
-				->set('size', $query->createNamedParameter($extraData['size']))
-				->set('componenttype', $query->createNamedParameter($extraData['componentType']))
-				->set('firstoccurence', $query->createNamedParameter($extraData['firstOccurence']))
-				->set('lastoccurence', $query->createNamedParameter($extraData['lastOccurence']))
-				->set('classification', $query->createNamedParameter($extraData['classification']))
-				->set('uid', $query->createNamedParameter($extraData['uid']))
-			->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)))
-			->andWhere($query->expr()->eq('uri', $query->createNamedParameter($objectUri)))
-			->execute();
-
-		$this->updateProperties($calendarId, $objectUri, $calendarData);
-
-		$data = $this->getCalendarObject($calendarId, $objectUri);
-		if (is_array($data)) {
-			$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::updateCalendarObject', new GenericEvent(
-				'\OCA\DAV\CalDAV\CalDavBackend::updateCalendarObject',
-				[
-					'calendarId' => $calendarId,
-					'calendarData' => $this->getCalendarById($calendarId),
-					'shares' => $this->getShares($calendarId),
-					'objectData' => $data,
-				]
-			));
-		}
-		$this->addChange($calendarId, $objectUri, 2);
-
-		return '"' . $extraData['etag'] . '"';
-	}
-
-	/**
-	 * @param int $calendarObjectId
-	 * @param int $classification
-	 */
-	public function setClassification($calendarObjectId, $classification) {
-		if (!in_array($classification, [
-			self::CLASSIFICATION_PUBLIC, self::CLASSIFICATION_PRIVATE, self::CLASSIFICATION_CONFIDENTIAL
-		])) {
-			throw new \InvalidArgumentException();
-		}
-		$query = $this->db->getQueryBuilder();
-		$query->update('calendarobjects')
-			->set('classification', $query->createNamedParameter($classification))
-			->where($query->expr()->eq('id', $query->createNamedParameter($calendarObjectId)))
-			->execute();
-	}
-
-	/**
-	 * Deletes an existing calendar object.
-	 *
-	 * The object uri is only the basename, or filename and not a full path.
-	 *
-	 * @param mixed $calendarId
-	 * @param string $objectUri
-	 * @return void
-	 */
-	function deleteCalendarObject($calendarId, $objectUri) {
-		$data = $this->getCalendarObject($calendarId, $objectUri);
-		if (is_array($data)) {
-			$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::deleteCalendarObject', new GenericEvent(
-				'\OCA\DAV\CalDAV\CalDavBackend::deleteCalendarObject',
-				[
-					'calendarId' => $calendarId,
-					'calendarData' => $this->getCalendarById($calendarId),
-					'shares' => $this->getShares($calendarId),
-					'objectData' => $data,
-				]
-			));
-		}
-
-		$stmt = $this->db->prepare('DELETE FROM `*PREFIX*calendarobjects` WHERE `calendarid` = ? AND `uri` = ?');
-		$stmt->execute([$calendarId, $objectUri]);
-
-		$this->purgeProperties($calendarId, $data['id']);
-
-		$this->addChange($calendarId, $objectUri, 3);
-	}
-
-	/**
-	 * Performs a calendar-query on the contents of this calendar.
-	 *
-	 * The calendar-query is defined in RFC4791 : CalDAV. Using the
-	 * calendar-query it is possible for a client to request a specific set of
-	 * object, based on contents of iCalendar properties, date-ranges and
-	 * iCalendar component types (VTODO, VEVENT).
-	 *
-	 * This method should just return a list of (relative) urls that match this
-	 * query.
-	 *
-	 * The list of filters are specified as an array. The exact array is
-	 * documented by Sabre\CalDAV\CalendarQueryParser.
-	 *
-	 * Note that it is extremely likely that getCalendarObject for every path
-	 * returned from this method will be called almost immediately after. You
-	 * may want to anticipate this to speed up these requests.
-	 *
-	 * This method provides a default implementation, which parses *all* the
-	 * iCalendar objects in the specified calendar.
-	 *
-	 * This default may well be good enough for personal use, and calendars
-	 * that aren't very large. But if you anticipate high usage, big calendars
-	 * or high loads, you are strongly advised to optimize certain paths.
-	 *
-	 * The best way to do so is override this method and to optimize
-	 * specifically for 'common filters'.
-	 *
-	 * Requests that are extremely common are:
-	 *   * requests for just VEVENTS
-	 *   * requests for just VTODO
-	 *   * requests with a time-range-filter on either VEVENT or VTODO.
-	 *
-	 * ..and combinations of these requests. It may not be worth it to try to
-	 * handle every possible situation and just rely on the (relatively
-	 * easy to use) CalendarQueryValidator to handle the rest.
-	 *
-	 * Note that especially time-range-filters may be difficult to parse. A
-	 * time-range filter specified on a VEVENT must for instance also handle
-	 * recurrence rules correctly.
-	 * A good example of how to interprete all these filters can also simply
-	 * be found in Sabre\CalDAV\CalendarQueryFilter. This class is as correct
-	 * as possible, so it gives you a good idea on what type of stuff you need
-	 * to think of.
-	 *
-	 * @param mixed $calendarId
-	 * @param array $filters
-	 * @return array
-	 */
-	function calendarQuery($calendarId, array $filters) {
-		$componentType = null;
-		$requirePostFilter = true;
-		$timeRange = null;
-
-		// if no filters were specified, we don't need to filter after a query
-		if (!$filters['prop-filters'] && !$filters['comp-filters']) {
-			$requirePostFilter = false;
-		}
-
-		// Figuring out if there's a component filter
-		if (count($filters['comp-filters']) > 0 && !$filters['comp-filters'][0]['is-not-defined']) {
-			$componentType = $filters['comp-filters'][0]['name'];
-
-			// Checking if we need post-filters
-			if (!$filters['prop-filters'] && !$filters['comp-filters'][0]['comp-filters'] && !$filters['comp-filters'][0]['time-range'] && !$filters['comp-filters'][0]['prop-filters']) {
-				$requirePostFilter = false;
-			}
-			// There was a time-range filter
-			if ($componentType == 'VEVENT' && isset($filters['comp-filters'][0]['time-range'])) {
-				$timeRange = $filters['comp-filters'][0]['time-range'];
-
-				// If start time OR the end time is not specified, we can do a
-				// 100% accurate mysql query.
-				if (!$filters['prop-filters'] && !$filters['comp-filters'][0]['comp-filters'] && !$filters['comp-filters'][0]['prop-filters'] && (!$timeRange['start'] || !$timeRange['end'])) {
-					$requirePostFilter = false;
-				}
-			}
-
-		}
-		$columns = ['uri'];
-		if ($requirePostFilter) {
-			$columns = ['uri', 'calendardata'];
-		}
-		$query = $this->db->getQueryBuilder();
-		$query->select($columns)
-			->from('calendarobjects')
-			->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)));
-
-		if ($componentType) {
-			$query->andWhere($query->expr()->eq('componenttype', $query->createNamedParameter($componentType)));
-		}
-
-		if ($timeRange && $timeRange['start']) {
-			$query->andWhere($query->expr()->gt('lastoccurence', $query->createNamedParameter($timeRange['start']->getTimeStamp())));
-		}
-		if ($timeRange && $timeRange['end']) {
-			$query->andWhere($query->expr()->lt('firstoccurence', $query->createNamedParameter($timeRange['end']->getTimeStamp())));
-		}
-
-		$stmt = $query->execute();
-
-		$result = [];
-		while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
-			if ($requirePostFilter) {
-				if (!$this->validateFilterForObject($row, $filters)) {
-					continue;
-				}
-			}
-			$result[] = $row['uri'];
-		}
-
-		return $result;
-	}
-
-	/**
-	 * custom Nextcloud search extension for CalDAV
-	 *
-	 * @param string $principalUri
-	 * @param array $filters
-	 * @param integer|null $limit
-	 * @param integer|null $offset
-	 * @return array
-	 */
-	public function calendarSearch($principalUri, array $filters, $limit=null, $offset=null) {
-		$calendars = $this->getCalendarsForUser($principalUri);
-		$ownCalendars = [];
-		$sharedCalendars = [];
-
-		$uriMapper = [];
-
-		foreach($calendars as $calendar) {
-			if ($calendar['{http://owncloud.org/ns}owner-principal'] === $principalUri) {
-				$ownCalendars[] = $calendar['id'];
-			} else {
-				$sharedCalendars[] = $calendar['id'];
-			}
-			$uriMapper[$calendar['id']] = $calendar['uri'];
-		}
-		if (count($ownCalendars) === 0 && count($sharedCalendars) === 0) {
-			return [];
-		}
-
-		$query = $this->db->getQueryBuilder();
-		// Calendar id expressions
-		$calendarExpressions = [];
-		foreach($ownCalendars as $id) {
-			$calendarExpressions[] = $query->expr()
-				->eq('c.calendarid', $query->createNamedParameter($id));
-		}
-		foreach($sharedCalendars as $id) {
-			$calendarExpressions[] = $query->expr()->andX(
-				$query->expr()->eq('c.calendarid',
-					$query->createNamedParameter($id)),
-				$query->expr()->eq('c.classification',
-					$query->createNamedParameter(self::CLASSIFICATION_PUBLIC))
-			);
-		}
-
-		if (count($calendarExpressions) === 1) {
-			$calExpr = $calendarExpressions[0];
-		} else {
-			$calExpr = call_user_func_array([$query->expr(), 'orX'], $calendarExpressions);
-		}
-
-		// Component expressions
-		$compExpressions = [];
-		foreach($filters['comps'] as $comp) {
-			$compExpressions[] = $query->expr()
-				->eq('c.componenttype', $query->createNamedParameter($comp));
-		}
-
-		if (count($compExpressions) === 1) {
-			$compExpr = $compExpressions[0];
-		} else {
-			$compExpr = call_user_func_array([$query->expr(), 'orX'], $compExpressions);
-		}
-
-		if (!isset($filters['props'])) {
-			$filters['props'] = [];
-		}
-		if (!isset($filters['params'])) {
-			$filters['params'] = [];
-		}
-
-		$propParamExpressions = [];
-		foreach($filters['props'] as $prop) {
-			$propParamExpressions[] = $query->expr()->andX(
-				$query->expr()->eq('i.name', $query->createNamedParameter($prop)),
-				$query->expr()->isNull('i.parameter')
-			);
-		}
-		foreach($filters['params'] as $param) {
-			$propParamExpressions[] = $query->expr()->andX(
-				$query->expr()->eq('i.name', $query->createNamedParameter($param['property'])),
-				$query->expr()->eq('i.parameter', $query->createNamedParameter($param['parameter']))
-			);
-		}
-
-		if (count($propParamExpressions) === 1) {
-			$propParamExpr = $propParamExpressions[0];
-		} else {
-			$propParamExpr = call_user_func_array([$query->expr(), 'orX'], $propParamExpressions);
-		}
-
-		$query->select(['c.calendarid', 'c.uri'])
-			->from($this->dbObjectPropertiesTable, 'i')
-			->join('i', 'calendarobjects', 'c', $query->expr()->eq('i.objectid', 'c.id'))
-			->where($calExpr)
-			->andWhere($compExpr)
-			->andWhere($propParamExpr)
-			->andWhere($query->expr()->iLike('i.value',
-				$query->createNamedParameter('%'.$this->db->escapeLikeParameter($filters['search-term']).'%')));
-
-		if ($offset) {
-			$query->setFirstResult($offset);
-		}
-		if ($limit) {
-			$query->setMaxResults($limit);
-		}
-
-		$stmt = $query->execute();
-
-		$result = [];
-		while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
-			$path = $uriMapper[$row['calendarid']] . '/' . $row['uri'];
-			if (!in_array($path, $result)) {
-				$result[] = $path;
-			}
-		}
-
-		return $result;
-	}
-
-	/**
-	 * Searches through all of a users calendars and calendar objects to find
-	 * an object with a specific UID.
-	 *
-	 * This method should return the path to this object, relative to the
-	 * calendar home, so this path usually only contains two parts:
-	 *
-	 * calendarpath/objectpath.ics
-	 *
-	 * If the uid is not found, return null.
-	 *
-	 * This method should only consider * objects that the principal owns, so
-	 * any calendars owned by other principals that also appear in this
-	 * collection should be ignored.
-	 *
-	 * @param string $principalUri
-	 * @param string $uid
-	 * @return string|null
-	 */
-	function getCalendarObjectByUID($principalUri, $uid) {
-
-		$query = $this->db->getQueryBuilder();
-		$query->selectAlias('c.uri', 'calendaruri')->selectAlias('co.uri', 'objecturi')
-			->from('calendarobjects', 'co')
-			->leftJoin('co', 'calendars', 'c', $query->expr()->eq('co.calendarid', 'c.id'))
-			->where($query->expr()->eq('c.principaluri', $query->createNamedParameter($principalUri)))
-			->andWhere($query->expr()->eq('co.uid', $query->createNamedParameter($uid)));
-
-		$stmt = $query->execute();
-
-		if ($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
-			return $row['calendaruri'] . '/' . $row['objecturi'];
-		}
-
-		return null;
-	}
-
-	/**
-	 * The getChanges method returns all the changes that have happened, since
-	 * the specified syncToken in the specified calendar.
-	 *
-	 * This function should return an array, such as the following:
-	 *
-	 * [
-	 *   'syncToken' => 'The current synctoken',
-	 *   'added'   => [
-	 *      'new.txt',
-	 *   ],
-	 *   'modified'   => [
-	 *      'modified.txt',
-	 *   ],
-	 *   'deleted' => [
-	 *      'foo.php.bak',
-	 *      'old.txt'
-	 *   ]
-	 * );
-	 *
-	 * The returned syncToken property should reflect the *current* syncToken
-	 * of the calendar, as reported in the {http://sabredav.org/ns}sync-token
-	 * property This is * needed here too, to ensure the operation is atomic.
-	 *
-	 * If the $syncToken argument is specified as null, this is an initial
-	 * sync, and all members should be reported.
-	 *
-	 * The modified property is an array of nodenames that have changed since
-	 * the last token.
-	 *
-	 * The deleted property is an array with nodenames, that have been deleted
-	 * from collection.
-	 *
-	 * The $syncLevel argument is basically the 'depth' of the report. If it's
-	 * 1, you only have to report changes that happened only directly in
-	 * immediate descendants. If it's 2, it should also include changes from
-	 * the nodes below the child collections. (grandchildren)
-	 *
-	 * The $limit argument allows a client to specify how many results should
-	 * be returned at most. If the limit is not specified, it should be treated
-	 * as infinite.
-	 *
-	 * If the limit (infinite or not) is higher than you're willing to return,
-	 * you should throw a Sabre\DAV\Exception\TooMuchMatches() exception.
-	 *
-	 * If the syncToken is expired (due to data cleanup) or unknown, you must
-	 * return null.
-	 *
-	 * The limit is 'suggestive'. You are free to ignore it.
-	 *
-	 * @param string $calendarId
-	 * @param string $syncToken
-	 * @param int $syncLevel
-	 * @param int $limit
-	 * @return array
-	 */
-	function getChangesForCalendar($calendarId, $syncToken, $syncLevel, $limit = null) {
-		// Current synctoken
-		$stmt = $this->db->prepare('SELECT `synctoken` FROM `*PREFIX*calendars` WHERE `id` = ?');
-		$stmt->execute([ $calendarId ]);
-		$currentToken = $stmt->fetchColumn(0);
-
-		if (is_null($currentToken)) {
-			return null;
-		}
-
-		$result = [
-			'syncToken' => $currentToken,
-			'added'     => [],
-			'modified'  => [],
-			'deleted'   => [],
-		];
-
-		if ($syncToken) {
-
-			$query = "SELECT `uri`, `operation` FROM `*PREFIX*calendarchanges` WHERE `synctoken` >= ? AND `synctoken` < ? AND `calendarid` = ? ORDER BY `synctoken`";
-			if ($limit>0) {
-				$query.= " `LIMIT` " . (int)$limit;
-			}
-
-			// Fetching all changes
-			$stmt = $this->db->prepare($query);
-			$stmt->execute([$syncToken, $currentToken, $calendarId]);
-
-			$changes = [];
-
-			// This loop ensures that any duplicates are overwritten, only the
-			// last change on a node is relevant.
-			while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
-
-				$changes[$row['uri']] = $row['operation'];
-
-			}
-
-			foreach($changes as $uri => $operation) {
-
-				switch($operation) {
-					case 1 :
-						$result['added'][] = $uri;
-						break;
-					case 2 :
-						$result['modified'][] = $uri;
-						break;
-					case 3 :
-						$result['deleted'][] = $uri;
-						break;
-				}
-
-			}
-		} else {
-			// No synctoken supplied, this is the initial sync.
-			$query = "SELECT `uri` FROM `*PREFIX*calendarobjects` WHERE `calendarid` = ?";
-			$stmt = $this->db->prepare($query);
-			$stmt->execute([$calendarId]);
-
-			$result['added'] = $stmt->fetchAll(\PDO::FETCH_COLUMN);
-		}
-		return $result;
-
-	}
-
-	/**
-	 * Returns a list of subscriptions for a principal.
-	 *
-	 * Every subscription is an array with the following keys:
-	 *  * id, a unique id that will be used by other functions to modify the
-	 *    subscription. This can be the same as the uri or a database key.
-	 *  * uri. This is just the 'base uri' or 'filename' of the subscription.
-	 *  * principaluri. The owner of the subscription. Almost always the same as
-	 *    principalUri passed to this method.
-	 *
-	 * Furthermore, all the subscription info must be returned too:
-	 *
-	 * 1. {DAV:}displayname
-	 * 2. {http://apple.com/ns/ical/}refreshrate
-	 * 3. {http://calendarserver.org/ns/}subscribed-strip-todos (omit if todos
-	 *    should not be stripped).
-	 * 4. {http://calendarserver.org/ns/}subscribed-strip-alarms (omit if alarms
-	 *    should not be stripped).
-	 * 5. {http://calendarserver.org/ns/}subscribed-strip-attachments (omit if
-	 *    attachments should not be stripped).
-	 * 6. {http://calendarserver.org/ns/}source (Must be a
-	 *     Sabre\DAV\Property\Href).
-	 * 7. {http://apple.com/ns/ical/}calendar-color
-	 * 8. {http://apple.com/ns/ical/}calendar-order
-	 * 9. {urn:ietf:params:xml:ns:caldav}supported-calendar-component-set
-	 *    (should just be an instance of
-	 *    Sabre\CalDAV\Property\SupportedCalendarComponentSet, with a bunch of
-	 *    default components).
-	 *
-	 * @param string $principalUri
-	 * @return array
-	 */
-	function getSubscriptionsForUser($principalUri) {
-		$fields = array_values($this->subscriptionPropertyMap);
-		$fields[] = 'id';
-		$fields[] = 'uri';
-		$fields[] = 'source';
-		$fields[] = 'principaluri';
-		$fields[] = 'lastmodified';
-
-		$query = $this->db->getQueryBuilder();
-		$query->select($fields)
-			->from('calendarsubscriptions')
-			->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
-			->orderBy('calendarorder', 'asc');
-		$stmt =$query->execute();
-
-		$subscriptions = [];
-		while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
-
-			$subscription = [
-				'id'           => $row['id'],
-				'uri'          => $row['uri'],
-				'principaluri' => $row['principaluri'],
-				'source'       => $row['source'],
-				'lastmodified' => $row['lastmodified'],
-
-				'{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet(['VTODO', 'VEVENT']),
-			];
-
-			foreach($this->subscriptionPropertyMap as $xmlName=>$dbName) {
-				if (!is_null($row[$dbName])) {
-					$subscription[$xmlName] = $row[$dbName];
-				}
-			}
-
-			$subscriptions[] = $subscription;
-
-		}
-
-		return $subscriptions;
-	}
-
-	/**
-	 * Creates a new subscription for a principal.
-	 *
-	 * If the creation was a success, an id must be returned that can be used to reference
-	 * this subscription in other methods, such as updateSubscription.
-	 *
-	 * @param string $principalUri
-	 * @param string $uri
-	 * @param array $properties
-	 * @return mixed
-	 */
-	function createSubscription($principalUri, $uri, array $properties) {
-
-		if (!isset($properties['{http://calendarserver.org/ns/}source'])) {
-			throw new Forbidden('The {http://calendarserver.org/ns/}source property is required when creating subscriptions');
-		}
-
-		$values = [
-			'principaluri' => $principalUri,
-			'uri'          => $uri,
-			'source'       => $properties['{http://calendarserver.org/ns/}source']->getHref(),
-			'lastmodified' => time(),
-		];
-
-		$propertiesBoolean = ['striptodos', 'stripalarms', 'stripattachments'];
-
-		foreach($this->subscriptionPropertyMap as $xmlName=>$dbName) {
-			if (array_key_exists($xmlName, $properties)) {
-					$values[$dbName] = $properties[$xmlName];
-					if (in_array($dbName, $propertiesBoolean)) {
-						$values[$dbName] = true;
-				}
-			}
-		}
-
-		$valuesToInsert = array();
-
-		$query = $this->db->getQueryBuilder();
-
-		foreach (array_keys($values) as $name) {
-			$valuesToInsert[$name] = $query->createNamedParameter($values[$name]);
-		}
-
-		$query->insert('calendarsubscriptions')
-			->values($valuesToInsert)
-			->execute();
-
-		return $this->db->lastInsertId('*PREFIX*calendarsubscriptions');
-	}
-
-	/**
-	 * Updates a subscription
-	 *
-	 * The list of mutations is stored in a Sabre\DAV\PropPatch object.
-	 * To do the actual updates, you must tell this object which properties
-	 * you're going to process with the handle() method.
-	 *
-	 * Calling the handle method is like telling the PropPatch object "I
-	 * promise I can handle updating this property".
-	 *
-	 * Read the PropPatch documentation for more info and examples.
-	 *
-	 * @param mixed $subscriptionId
-	 * @param PropPatch $propPatch
-	 * @return void
-	 */
-	function updateSubscription($subscriptionId, PropPatch $propPatch) {
-		$supportedProperties = array_keys($this->subscriptionPropertyMap);
-		$supportedProperties[] = '{http://calendarserver.org/ns/}source';
-
-		$propPatch->handle($supportedProperties, function($mutations) use ($subscriptionId) {
-
-			$newValues = [];
-
-			foreach($mutations as $propertyName=>$propertyValue) {
-				if ($propertyName === '{http://calendarserver.org/ns/}source') {
-					$newValues['source'] = $propertyValue->getHref();
-				} else {
-					$fieldName = $this->subscriptionPropertyMap[$propertyName];
-					$newValues[$fieldName] = $propertyValue;
-				}
-			}
-
-			$query = $this->db->getQueryBuilder();
-			$query->update('calendarsubscriptions')
-				->set('lastmodified', $query->createNamedParameter(time()));
-			foreach($newValues as $fieldName=>$value) {
-				$query->set($fieldName, $query->createNamedParameter($value));
-			}
-			$query->where($query->expr()->eq('id', $query->createNamedParameter($subscriptionId)))
-				->execute();
-
-			return true;
-
-		});
-	}
-
-	/**
-	 * Deletes a subscription.
-	 *
-	 * @param mixed $subscriptionId
-	 * @return void
-	 */
-	function deleteSubscription($subscriptionId) {
-		$query = $this->db->getQueryBuilder();
-		$query->delete('calendarsubscriptions')
-			->where($query->expr()->eq('id', $query->createNamedParameter($subscriptionId)))
-			->execute();
-	}
-
-	/**
-	 * Returns a single scheduling object for the inbox collection.
-	 *
-	 * The returned array should contain the following elements:
-	 *   * uri - A unique basename for the object. This will be used to
-	 *           construct a full uri.
-	 *   * calendardata - The iCalendar object
-	 *   * lastmodified - The last modification date. Can be an int for a unix
-	 *                    timestamp, or a PHP DateTime object.
-	 *   * etag - A unique token that must change if the object changed.
-	 *   * size - The size of the object, in bytes.
-	 *
-	 * @param string $principalUri
-	 * @param string $objectUri
-	 * @return array
-	 */
-	function getSchedulingObject($principalUri, $objectUri) {
-		$query = $this->db->getQueryBuilder();
-		$stmt = $query->select(['uri', 'calendardata', 'lastmodified', 'etag', 'size'])
-			->from('schedulingobjects')
-			->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
-			->andWhere($query->expr()->eq('uri', $query->createNamedParameter($objectUri)))
-			->execute();
-
-		$row = $stmt->fetch(\PDO::FETCH_ASSOC);
-
-		if(!$row) {
-			return null;
-		}
-
-		return [
-				'uri'          => $row['uri'],
-				'calendardata' => $row['calendardata'],
-				'lastmodified' => $row['lastmodified'],
-				'etag'         => '"' . $row['etag'] . '"',
-				'size'         => (int)$row['size'],
-		];
-	}
-
-	/**
-	 * Returns all scheduling objects for the inbox collection.
-	 *
-	 * These objects should be returned as an array. Every item in the array
-	 * should follow the same structure as returned from getSchedulingObject.
-	 *
-	 * The main difference is that 'calendardata' is optional.
-	 *
-	 * @param string $principalUri
-	 * @return array
-	 */
-	function getSchedulingObjects($principalUri) {
-		$query = $this->db->getQueryBuilder();
-		$stmt = $query->select(['uri', 'calendardata', 'lastmodified', 'etag', 'size'])
-				->from('schedulingobjects')
-				->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
-				->execute();
-
-		$result = [];
-		foreach($stmt->fetchAll(\PDO::FETCH_ASSOC) as $row) {
-			$result[] = [
-					'calendardata' => $row['calendardata'],
-					'uri'          => $row['uri'],
-					'lastmodified' => $row['lastmodified'],
-					'etag'         => '"' . $row['etag'] . '"',
-					'size'         => (int)$row['size'],
-			];
-		}
-
-		return $result;
-	}
-
-	/**
-	 * Deletes a scheduling object from the inbox collection.
-	 *
-	 * @param string $principalUri
-	 * @param string $objectUri
-	 * @return void
-	 */
-	function deleteSchedulingObject($principalUri, $objectUri) {
-		$query = $this->db->getQueryBuilder();
-		$query->delete('schedulingobjects')
-				->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
-				->andWhere($query->expr()->eq('uri', $query->createNamedParameter($objectUri)))
-				->execute();
-	}
-
-	/**
-	 * Creates a new scheduling object. This should land in a users' inbox.
-	 *
-	 * @param string $principalUri
-	 * @param string $objectUri
-	 * @param string $objectData
-	 * @return void
-	 */
-	function createSchedulingObject($principalUri, $objectUri, $objectData) {
-		$query = $this->db->getQueryBuilder();
-		$query->insert('schedulingobjects')
-			->values([
-				'principaluri' => $query->createNamedParameter($principalUri),
-				'calendardata' => $query->createNamedParameter($objectData),
-				'uri' => $query->createNamedParameter($objectUri),
-				'lastmodified' => $query->createNamedParameter(time()),
-				'etag' => $query->createNamedParameter(md5($objectData)),
-				'size' => $query->createNamedParameter(strlen($objectData))
-			])
-			->execute();
-	}
-
-	/**
-	 * Adds a change record to the calendarchanges table.
-	 *
-	 * @param mixed $calendarId
-	 * @param string $objectUri
-	 * @param int $operation 1 = add, 2 = modify, 3 = delete.
-	 * @return void
-	 */
-	protected function addChange($calendarId, $objectUri, $operation) {
-
-		$stmt = $this->db->prepare('INSERT INTO `*PREFIX*calendarchanges` (`uri`, `synctoken`, `calendarid`, `operation`) SELECT ?, `synctoken`, ?, ? FROM `*PREFIX*calendars` WHERE `id` = ?');
-		$stmt->execute([
-			$objectUri,
-			$calendarId,
-			$operation,
-			$calendarId
-		]);
-		$stmt = $this->db->prepare('UPDATE `*PREFIX*calendars` SET `synctoken` = `synctoken` + 1 WHERE `id` = ?');
-		$stmt->execute([
-			$calendarId
-		]);
-
-	}
-
-	/**
-	 * Parses some information from calendar objects, used for optimized
-	 * calendar-queries.
-	 *
-	 * Returns an array with the following keys:
-	 *   * etag - An md5 checksum of the object without the quotes.
-	 *   * size - Size of the object in bytes
-	 *   * componentType - VEVENT, VTODO or VJOURNAL
-	 *   * firstOccurence
-	 *   * lastOccurence
-	 *   * uid - value of the UID property
-	 *
-	 * @param string $calendarData
-	 * @return array
-	 */
-	public function getDenormalizedData($calendarData) {
-
-		$vObject = Reader::read($calendarData);
-		$componentType = null;
-		$component = null;
-		$firstOccurrence = null;
-		$lastOccurrence = null;
-		$uid = null;
-		$classification = self::CLASSIFICATION_PUBLIC;
-		foreach($vObject->getComponents() as $component) {
-			if ($component->name!=='VTIMEZONE') {
-				$componentType = $component->name;
-				$uid = (string)$component->UID;
-				break;
-			}
-		}
-		if (!$componentType) {
-			throw new \Sabre\DAV\Exception\BadRequest('Calendar objects must have a VJOURNAL, VEVENT or VTODO component');
-		}
-		if ($componentType === 'VEVENT' && $component->DTSTART) {
-			$firstOccurrence = $component->DTSTART->getDateTime()->getTimeStamp();
-			// Finding the last occurrence is a bit harder
-			if (!isset($component->RRULE)) {
-				if (isset($component->DTEND)) {
-					$lastOccurrence = $component->DTEND->getDateTime()->getTimeStamp();
-				} elseif (isset($component->DURATION)) {
-					$endDate = clone $component->DTSTART->getDateTime();
-					$endDate->add(DateTimeParser::parse($component->DURATION->getValue()));
-					$lastOccurrence = $endDate->getTimeStamp();
-				} elseif (!$component->DTSTART->hasTime()) {
-					$endDate = clone $component->DTSTART->getDateTime();
-					$endDate->modify('+1 day');
-					$lastOccurrence = $endDate->getTimeStamp();
-				} else {
-					$lastOccurrence = $firstOccurrence;
-				}
-			} else {
-				$it = new EventIterator($vObject, (string)$component->UID);
-				$maxDate = new \DateTime(self::MAX_DATE);
-				if ($it->isInfinite()) {
-					$lastOccurrence = $maxDate->getTimestamp();
-				} else {
-					$end = $it->getDtEnd();
-					while($it->valid() && $end < $maxDate) {
-						$end = $it->getDtEnd();
-						$it->next();
-
-					}
-					$lastOccurrence = $end->getTimestamp();
-				}
-
-			}
-		}
-
-		if ($component->CLASS) {
-			$classification = CalDavBackend::CLASSIFICATION_PRIVATE;
-			switch ($component->CLASS->getValue()) {
-				case 'PUBLIC':
-					$classification = CalDavBackend::CLASSIFICATION_PUBLIC;
-					break;
-				case 'CONFIDENTIAL':
-					$classification = CalDavBackend::CLASSIFICATION_CONFIDENTIAL;
-					break;
-			}
-		}
-		return [
-			'etag' => md5($calendarData),
-			'size' => strlen($calendarData),
-			'componentType' => $componentType,
-			'firstOccurence' => is_null($firstOccurrence) ? null : max(0, $firstOccurrence),
-			'lastOccurence'  => $lastOccurrence,
-			'uid' => $uid,
-			'classification' => $classification
-		];
-
-	}
-
-	private function readBlob($cardData) {
-		if (is_resource($cardData)) {
-			return stream_get_contents($cardData);
-		}
-
-		return $cardData;
-	}
-
-	/**
-	 * @param IShareable $shareable
-	 * @param array $add
-	 * @param array $remove
-	 */
-	public function updateShares($shareable, $add, $remove) {
-		$calendarId = $shareable->getResourceId();
-		$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::updateShares', new GenericEvent(
-			'\OCA\DAV\CalDAV\CalDavBackend::updateShares',
-			[
-				'calendarId' => $calendarId,
-				'calendarData' => $this->getCalendarById($calendarId),
-				'shares' => $this->getShares($calendarId),
-				'add' => $add,
-				'remove' => $remove,
-			]));
-		$this->sharingBackend->updateShares($shareable, $add, $remove);
-	}
-
-	/**
-	 * @param int $resourceId
-	 * @return array
-	 */
-	public function getShares($resourceId) {
-		return $this->sharingBackend->getShares($resourceId);
-	}
-
-	/**
-	 * @param boolean $value
-	 * @param \OCA\DAV\CalDAV\Calendar $calendar
-	 * @return string|null
-	 */
-	public function setPublishStatus($value, $calendar) {
-		$query = $this->db->getQueryBuilder();
-		if ($value) {
-			$publicUri = $this->random->generate(16, ISecureRandom::CHAR_HUMAN_READABLE);
-			$query->insert('dav_shares')
-				->values([
-					'principaluri' => $query->createNamedParameter($calendar->getPrincipalURI()),
-					'type' => $query->createNamedParameter('calendar'),
-					'access' => $query->createNamedParameter(self::ACCESS_PUBLIC),
-					'resourceid' => $query->createNamedParameter($calendar->getResourceId()),
-					'publicuri' => $query->createNamedParameter($publicUri)
-				]);
-			$query->execute();
-			return $publicUri;
-		}
-		$query->delete('dav_shares')
-			->where($query->expr()->eq('resourceid', $query->createNamedParameter($calendar->getResourceId())))
-			->andWhere($query->expr()->eq('access', $query->createNamedParameter(self::ACCESS_PUBLIC)));
-		$query->execute();
-		return null;
-	}
-
-	/**
-	 * @param \OCA\DAV\CalDAV\Calendar $calendar
-	 * @return mixed
-	 */
-	public function getPublishStatus($calendar) {
-		$query = $this->db->getQueryBuilder();
-		$result = $query->select('publicuri')
-			->from('dav_shares')
-			->where($query->expr()->eq('resourceid', $query->createNamedParameter($calendar->getResourceId())))
-			->andWhere($query->expr()->eq('access', $query->createNamedParameter(self::ACCESS_PUBLIC)))
-			->execute();
-
-		$row = $result->fetch();
-		$result->closeCursor();
-		return $row ? reset($row) : false;
-	}
-
-	/**
-	 * @param int $resourceId
-	 * @param array $acl
-	 * @return array
-	 */
-	public function applyShareAcl($resourceId, $acl) {
-		return $this->sharingBackend->applyShareAcl($resourceId, $acl);
-	}
-
-
-
-	/**
-	 * update properties table
-	 *
-	 * @param int $calendarId
-	 * @param string $objectUri
-	 * @param string $calendarData
-	 */
-	public function updateProperties($calendarId, $objectUri, $calendarData) {
-		$objectId = $this->getCalendarObjectId($calendarId, $objectUri);
-
-		try {
-			$vCalendar = $this->readCalendarData($calendarData);
-		} catch (\Exception $ex) {
-			return;
-		}
-
-		$this->purgeProperties($calendarId, $objectId);
-
-		$query = $this->db->getQueryBuilder();
-		$query->insert($this->dbObjectPropertiesTable)
-			->values(
-				[
-					'calendarid' => $query->createNamedParameter($calendarId),
-					'objectid' => $query->createNamedParameter($objectId),
-					'name' => $query->createParameter('name'),
-					'parameter' => $query->createParameter('parameter'),
-					'value' => $query->createParameter('value'),
-				]
-			);
-
-		$indexComponents = ['VEVENT', 'VJOURNAL', 'VTODO'];
-		foreach ($vCalendar->getComponents() as $component) {
-			if (!in_array($component->name, $indexComponents)) {
-				continue;
-			}
-
-			foreach ($component->children() as $property) {
-				if (in_array($property->name, self::$indexProperties)) {
-					$value = $property->getValue();
-					// is this a shitty db?
-					if (!$this->db->supports4ByteText()) {
-						$value = preg_replace('/[\x{10000}-\x{10FFFF}]/u', "\xEF\xBF\xBD", $value);
-					}
-					$value = substr($value, 0, 254);
-
-					$query->setParameter('name', $property->name);
-					$query->setParameter('parameter', null);
-					$query->setParameter('value', $value);
-					$query->execute();
-				}
-
-				if (in_array($property->name, array_keys(self::$indexParameters))) {
-					$parameters = $property->parameters();
-					$indexedParametersForProperty = self::$indexParameters[$property->name];
-
-					foreach ($parameters as $key => $value) {
-						if (in_array($key, $indexedParametersForProperty)) {
-							// is this a shitty db?
-							if ($this->db->supports4ByteText()) {
-								$value = preg_replace('/[\x{10000}-\x{10FFFF}]/u', "\xEF\xBF\xBD", $value);
-							}
-							$value = substr($value, 0, 254);
-
-							$query->setParameter('name', $property->name);
-							$query->setParameter('parameter', substr($key, 0, 254));
-							$query->setParameter('value', substr($value, 0, 254));
-							$query->execute();
-						}
-					}
-				}
-			}
-		}
-	}
-
-	/**
-	 * read VCalendar data into a VCalendar object
-	 *
-	 * @param string $objectData
-	 * @return VCalendar
-	 */
-	protected function readCalendarData($objectData) {
-		return Reader::read($objectData);
-	}
-
-	/**
-	 * delete all properties from a given calendar object
-	 *
-	 * @param int $calendarId
-	 * @param int $objectId
-	 */
-	protected function purgeProperties($calendarId, $objectId) {
-		$query = $this->db->getQueryBuilder();
-		$query->delete($this->dbObjectPropertiesTable)
-			->where($query->expr()->eq('objectid', $query->createNamedParameter($objectId)))
-			->andWhere($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)));
-		$query->execute();
-	}
-
-	/**
-	 * get ID from a given calendar object
-	 *
-	 * @param int $calendarId
-	 * @param string $uri
-	 * @return int
-	 */
-	protected function getCalendarObjectId($calendarId, $uri) {
-		$query = $this->db->getQueryBuilder();
-		$query->select('id')->from('calendarobjects')
-			->where($query->expr()->eq('uri', $query->createNamedParameter($uri)))
-			->andWhere($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)));
-
-		$result = $query->execute();
-		$objectIds = $result->fetch();
-		$result->closeCursor();
-
-		if (!isset($objectIds['id'])) {
-			throw new \InvalidArgumentException('Calendarobject does not exists: ' . $uri);
-		}
-
-		return (int)$objectIds['id'];
-	}
-
-	private function convertPrincipal($principalUri, $toV2) {
-		if ($this->principalBackend->getPrincipalPrefix() === 'principals') {
-			list(, $name) = URLUtil::splitPath($principalUri);
-			if ($toV2 === true) {
-				return "principals/users/$name";
-			}
-			return "principals/$name";
-		}
-		return $principalUri;
-	}
-
-	private function addOwnerPrincipal(&$calendarInfo) {
-		$ownerPrincipalKey = '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}owner-principal';
-		$displaynameKey = '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_NEXTCLOUD . '}owner-displayname';
-		if (isset($calendarInfo[$ownerPrincipalKey])) {
-			$uri = $calendarInfo[$ownerPrincipalKey];
-		} else {
-			$uri = $calendarInfo['principaluri'];
-		}
-
-		$principalInformation = $this->principalBackend->getPrincipalByPath($uri);
-		if (isset($principalInformation['{DAV:}displayname'])) {
-			$calendarInfo[$displaynameKey] = $principalInformation['{DAV:}displayname'];
-		}
-	}
+    /**
+     * @return array
+     */
+    public function getPublicCalendars() {
+        $fields = array_values($this->propertyMap);
+        $fields[] = 'a.id';
+        $fields[] = 'a.uri';
+        $fields[] = 'a.synctoken';
+        $fields[] = 'a.components';
+        $fields[] = 'a.principaluri';
+        $fields[] = 'a.transparent';
+        $fields[] = 's.access';
+        $fields[] = 's.publicuri';
+        $calendars = [];
+        $query = $this->db->getQueryBuilder();
+        $result = $query->select($fields)
+            ->from('dav_shares', 's')
+            ->join('s', 'calendars', 'a', $query->expr()->eq('s.resourceid', 'a.id'))
+            ->where($query->expr()->in('s.access', $query->createNamedParameter(self::ACCESS_PUBLIC)))
+            ->andWhere($query->expr()->eq('s.type', $query->createNamedParameter('calendar')))
+            ->execute();
+
+        while($row = $result->fetch()) {
+            list(, $name) = URLUtil::splitPath($row['principaluri']);
+            $row['displayname'] = $row['displayname'] . "($name)";
+            $components = [];
+            if ($row['components']) {
+                $components = explode(',',$row['components']);
+            }
+            $calendar = [
+                'id' => $row['id'],
+                'uri' => $row['publicuri'],
+                'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
+                '{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
+                '{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
+                '{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
+                '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
+                '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}owner-principal' => $this->convertPrincipal($row['principaluri'], $this->legacyEndpoint),
+                '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}read-only' => (int)$row['access'] === Backend::ACCESS_READ,
+                '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}public' => (int)$row['access'] === self::ACCESS_PUBLIC,
+            ];
+
+            foreach($this->propertyMap as $xmlName=>$dbName) {
+                $calendar[$xmlName] = $row[$dbName];
+            }
+
+            $this->addOwnerPrincipal($calendar);
+
+            if (!isset($calendars[$calendar['id']])) {
+                $calendars[$calendar['id']] = $calendar;
+            }
+        }
+        $result->closeCursor();
+
+        return array_values($calendars);
+    }
+
+    /**
+     * @param string $uri
+     * @return array
+     * @throws NotFound
+     */
+    public function getPublicCalendar($uri) {
+        $fields = array_values($this->propertyMap);
+        $fields[] = 'a.id';
+        $fields[] = 'a.uri';
+        $fields[] = 'a.synctoken';
+        $fields[] = 'a.components';
+        $fields[] = 'a.principaluri';
+        $fields[] = 'a.transparent';
+        $fields[] = 's.access';
+        $fields[] = 's.publicuri';
+        $query = $this->db->getQueryBuilder();
+        $result = $query->select($fields)
+            ->from('dav_shares', 's')
+            ->join('s', 'calendars', 'a', $query->expr()->eq('s.resourceid', 'a.id'))
+            ->where($query->expr()->in('s.access', $query->createNamedParameter(self::ACCESS_PUBLIC)))
+            ->andWhere($query->expr()->eq('s.type', $query->createNamedParameter('calendar')))
+            ->andWhere($query->expr()->eq('s.publicuri', $query->createNamedParameter($uri)))
+            ->execute();
+
+        $row = $result->fetch(\PDO::FETCH_ASSOC);
+
+        $result->closeCursor();
+
+        if ($row === false) {
+            throw new NotFound('Node with name \'' . $uri . '\' could not be found');
+        }
+
+        list(, $name) = URLUtil::splitPath($row['principaluri']);
+        $row['displayname'] = $row['displayname'] . ' ' . "($name)";
+        $components = [];
+        if ($row['components']) {
+            $components = explode(',',$row['components']);
+        }
+        $calendar = [
+            'id' => $row['id'],
+            'uri' => $row['publicuri'],
+            'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
+            '{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
+            '{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
+            '{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
+            '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
+            '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}owner-principal' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
+            '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}read-only' => (int)$row['access'] === Backend::ACCESS_READ,
+            '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}public' => (int)$row['access'] === self::ACCESS_PUBLIC,
+        ];
+
+        foreach($this->propertyMap as $xmlName=>$dbName) {
+            $calendar[$xmlName] = $row[$dbName];
+        }
+
+        $this->addOwnerPrincipal($calendar);
+
+        return $calendar;
+
+    }
+
+    /**
+     * @param string $principal
+     * @param string $uri
+     * @return array|null
+     */
+    public function getCalendarByUri($principal, $uri) {
+        $fields = array_values($this->propertyMap);
+        $fields[] = 'id';
+        $fields[] = 'uri';
+        $fields[] = 'synctoken';
+        $fields[] = 'components';
+        $fields[] = 'principaluri';
+        $fields[] = 'transparent';
+
+        // Making fields a comma-delimited list
+        $query = $this->db->getQueryBuilder();
+        $query->select($fields)->from('calendars')
+            ->where($query->expr()->eq('uri', $query->createNamedParameter($uri)))
+            ->andWhere($query->expr()->eq('principaluri', $query->createNamedParameter($principal)))
+            ->setMaxResults(1);
+        $stmt = $query->execute();
+
+        $row = $stmt->fetch(\PDO::FETCH_ASSOC);
+        $stmt->closeCursor();
+        if ($row === false) {
+            return null;
+        }
+
+        $components = [];
+        if ($row['components']) {
+            $components = explode(',',$row['components']);
+        }
+
+        $calendar = [
+            'id' => $row['id'],
+            'uri' => $row['uri'],
+            'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
+            '{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
+            '{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
+            '{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
+            '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
+        ];
+
+        foreach($this->propertyMap as $xmlName=>$dbName) {
+            $calendar[$xmlName] = $row[$dbName];
+        }
+
+        $this->addOwnerPrincipal($calendar);
+
+        return $calendar;
+    }
+
+    public function getCalendarById($calendarId) {
+        $fields = array_values($this->propertyMap);
+        $fields[] = 'id';
+        $fields[] = 'uri';
+        $fields[] = 'synctoken';
+        $fields[] = 'components';
+        $fields[] = 'principaluri';
+        $fields[] = 'transparent';
+
+        // Making fields a comma-delimited list
+        $query = $this->db->getQueryBuilder();
+        $query->select($fields)->from('calendars')
+            ->where($query->expr()->eq('id', $query->createNamedParameter($calendarId)))
+            ->setMaxResults(1);
+        $stmt = $query->execute();
+
+        $row = $stmt->fetch(\PDO::FETCH_ASSOC);
+        $stmt->closeCursor();
+        if ($row === false) {
+            return null;
+        }
+
+        $components = [];
+        if ($row['components']) {
+            $components = explode(',',$row['components']);
+        }
+
+        $calendar = [
+            'id' => $row['id'],
+            'uri' => $row['uri'],
+            'principaluri' => $this->convertPrincipal($row['principaluri'], !$this->legacyEndpoint),
+            '{' . Plugin::NS_CALENDARSERVER . '}getctag' => 'http://sabre.io/ns/sync/' . ($row['synctoken']?$row['synctoken']:'0'),
+            '{http://sabredav.org/ns}sync-token' => $row['synctoken']?$row['synctoken']:'0',
+            '{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet($components),
+            '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' => new ScheduleCalendarTransp($row['transparent']?'transparent':'opaque'),
+        ];
+
+        foreach($this->propertyMap as $xmlName=>$dbName) {
+            $calendar[$xmlName] = $row[$dbName];
+        }
+
+        $this->addOwnerPrincipal($calendar);
+
+        return $calendar;
+    }
+
+    /**
+     * Creates a new calendar for a principal.
+     *
+     * If the creation was a success, an id must be returned that can be used to reference
+     * this calendar in other methods, such as updateCalendar.
+     *
+     * @param string $principalUri
+     * @param string $calendarUri
+     * @param array $properties
+     * @return int
+     */
+    function createCalendar($principalUri, $calendarUri, array $properties) {
+        $values = [
+            'principaluri' => $this->convertPrincipal($principalUri, true),
+            'uri'          => $calendarUri,
+            'synctoken'    => 1,
+            'transparent'  => 0,
+            'components'   => 'VEVENT,VTODO',
+            'displayname'  => $calendarUri
+        ];
+
+        // Default value
+        $sccs = '{urn:ietf:params:xml:ns:caldav}supported-calendar-component-set';
+        if (isset($properties[$sccs])) {
+            if (!($properties[$sccs] instanceof SupportedCalendarComponentSet)) {
+                throw new DAV\Exception('The ' . $sccs . ' property must be of type: \Sabre\CalDAV\Property\SupportedCalendarComponentSet');
+            }
+            $values['components'] = implode(',',$properties[$sccs]->getValue());
+        }
+        $transp = '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp';
+        if (isset($properties[$transp])) {
+            $values['transparent'] = (int) ($properties[$transp]->getValue() === 'transparent');
+        }
+
+        foreach($this->propertyMap as $xmlName=>$dbName) {
+            if (isset($properties[$xmlName])) {
+                $values[$dbName] = $properties[$xmlName];
+            }
+        }
+
+        $query = $this->db->getQueryBuilder();
+        $query->insert('calendars');
+        foreach($values as $column => $value) {
+            $query->setValue($column, $query->createNamedParameter($value));
+        }
+        $query->execute();
+        $calendarId = $query->getLastInsertId();
+
+        $this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::createCalendar', new GenericEvent(
+            '\OCA\DAV\CalDAV\CalDavBackend::createCalendar',
+            [
+                'calendarId' => $calendarId,
+                'calendarData' => $this->getCalendarById($calendarId),
+        ]));
+
+        return $calendarId;
+    }
+
+    /**
+     * Updates properties for a calendar.
+     *
+     * The list of mutations is stored in a Sabre\DAV\PropPatch object.
+     * To do the actual updates, you must tell this object which properties
+     * you're going to process with the handle() method.
+     *
+     * Calling the handle method is like telling the PropPatch object "I
+     * promise I can handle updating this property".
+     *
+     * Read the PropPatch documentation for more info and examples.
+     *
+     * @param PropPatch $propPatch
+     * @return void
+     */
+    function updateCalendar($calendarId, PropPatch $propPatch) {
+        $supportedProperties = array_keys($this->propertyMap);
+        $supportedProperties[] = '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp';
+
+        $propPatch->handle($supportedProperties, function($mutations) use ($calendarId) {
+            $newValues = [];
+            foreach ($mutations as $propertyName => $propertyValue) {
+
+                switch ($propertyName) {
+                    case '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp' :
+                        $fieldName = 'transparent';
+                        $newValues[$fieldName] = (int) ($propertyValue->getValue() === 'transparent');
+                        break;
+                    default :
+                        $fieldName = $this->propertyMap[$propertyName];
+                        $newValues[$fieldName] = $propertyValue;
+                        break;
+                }
+
+            }
+            $query = $this->db->getQueryBuilder();
+            $query->update('calendars');
+            foreach ($newValues as $fieldName => $value) {
+                $query->set($fieldName, $query->createNamedParameter($value));
+            }
+            $query->where($query->expr()->eq('id', $query->createNamedParameter($calendarId)));
+            $query->execute();
+
+            $this->addChange($calendarId, "", 2);
+
+            $this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::updateCalendar', new GenericEvent(
+                '\OCA\DAV\CalDAV\CalDavBackend::updateCalendar',
+                [
+                    'calendarId' => $calendarId,
+                    'calendarData' => $this->getCalendarById($calendarId),
+                    'shares' => $this->getShares($calendarId),
+                    'propertyMutations' => $mutations,
+            ]));
+
+            return true;
+        });
+    }
+
+    /**
+     * Delete a calendar and all it's objects
+     *
+     * @param mixed $calendarId
+     * @return void
+     */
+    function deleteCalendar($calendarId) {
+        $this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::deleteCalendar', new GenericEvent(
+            '\OCA\DAV\CalDAV\CalDavBackend::deleteCalendar',
+            [
+                'calendarId' => $calendarId,
+                'calendarData' => $this->getCalendarById($calendarId),
+                'shares' => $this->getShares($calendarId),
+        ]));
+
+        $stmt = $this->db->prepare('DELETE FROM `*PREFIX*calendarobjects` WHERE `calendarid` = ?');
+        $stmt->execute([$calendarId]);
+
+        $stmt = $this->db->prepare('DELETE FROM `*PREFIX*calendars` WHERE `id` = ?');
+        $stmt->execute([$calendarId]);
+
+        $stmt = $this->db->prepare('DELETE FROM `*PREFIX*calendarchanges` WHERE `calendarid` = ?');
+        $stmt->execute([$calendarId]);
+
+        $this->sharingBackend->deleteAllShares($calendarId);
+
+        $query = $this->db->getQueryBuilder();
+        $query->delete($this->dbObjectPropertiesTable)
+            ->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)))
+            ->execute();
+    }
+
+    /**
+     * Delete all of an user's shares
+     *
+     * @param string $principaluri
+     * @return void
+     */
+    function deleteAllSharesByUser($principaluri) {
+        $this->sharingBackend->deleteAllSharesByUser($principaluri);
+    }
+
+    /**
+     * Returns all calendar objects within a calendar.
+     *
+     * Every item contains an array with the following keys:
+     *   * calendardata - The iCalendar-compatible calendar data
+     *   * uri - a unique key which will be used to construct the uri. This can
+     *     be any arbitrary string, but making sure it ends with '.ics' is a
+     *     good idea. This is only the basename, or filename, not the full
+     *     path.
+     *   * lastmodified - a timestamp of the last modification time
+     *   * etag - An arbitrary string, surrounded by double-quotes. (e.g.:
+     *   '"abcdef"')
+     *   * size - The size of the calendar objects, in bytes.
+     *   * component - optional, a string containing the type of object, such
+     *     as 'vevent' or 'vtodo'. If specified, this will be used to populate
+     *     the Content-Type header.
+     *
+     * Note that the etag is optional, but it's highly encouraged to return for
+     * speed reasons.
+     *
+     * The calendardata is also optional. If it's not returned
+     * 'getCalendarObject' will be called later, which *is* expected to return
+     * calendardata.
+     *
+     * If neither etag or size are specified, the calendardata will be
+     * used/fetched to determine these numbers. If both are specified the
+     * amount of times this is needed is reduced by a great degree.
+     *
+     * @param mixed $calendarId
+     * @return array
+     */
+    function getCalendarObjects($calendarId) {
+        $query = $this->db->getQueryBuilder();
+        $query->select(['id', 'uri', 'lastmodified', 'etag', 'calendarid', 'size', 'componenttype', 'classification'])
+            ->from('calendarobjects')
+            ->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)));
+        $stmt = $query->execute();
+
+        $result = [];
+        foreach($stmt->fetchAll(\PDO::FETCH_ASSOC) as $row) {
+            $result[] = [
+                    'id'           => $row['id'],
+                    'uri'          => $row['uri'],
+                    'lastmodified' => $row['lastmodified'],
+                    'etag'         => '"' . $row['etag'] . '"',
+                    'calendarid'   => $row['calendarid'],
+                    'size'         => (int)$row['size'],
+                    'component'    => strtolower($row['componenttype']),
+                    'classification'=> (int)$row['classification']
+            ];
+        }
+
+        return $result;
+    }
+
+    /**
+     * Returns information from a single calendar object, based on it's object
+     * uri.
+     *
+     * The object uri is only the basename, or filename and not a full path.
+     *
+     * The returned array must have the same keys as getCalendarObjects. The
+     * 'calendardata' object is required here though, while it's not required
+     * for getCalendarObjects.
+     *
+     * This method must return null if the object did not exist.
+     *
+     * @param mixed $calendarId
+     * @param string $objectUri
+     * @return array|null
+     */
+    function getCalendarObject($calendarId, $objectUri) {
+
+        $query = $this->db->getQueryBuilder();
+        $query->select(['id', 'uri', 'lastmodified', 'etag', 'calendarid', 'size', 'calendardata', 'componenttype', 'classification'])
+                ->from('calendarobjects')
+                ->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)))
+                ->andWhere($query->expr()->eq('uri', $query->createNamedParameter($objectUri)));
+        $stmt = $query->execute();
+        $row = $stmt->fetch(\PDO::FETCH_ASSOC);
+
+        if(!$row) return null;
+
+        return [
+                'id'            => $row['id'],
+                'uri'           => $row['uri'],
+                'lastmodified'  => $row['lastmodified'],
+                'etag'          => '"' . $row['etag'] . '"',
+                'calendarid'    => $row['calendarid'],
+                'size'          => (int)$row['size'],
+                'calendardata'  => $this->readBlob($row['calendardata']),
+                'component'     => strtolower($row['componenttype']),
+                'classification'=> (int)$row['classification']
+        ];
+    }
+
+    /**
+     * Returns a list of calendar objects.
+     *
+     * This method should work identical to getCalendarObject, but instead
+     * return all the calendar objects in the list as an array.
+     *
+     * If the backend supports this, it may allow for some speed-ups.
+     *
+     * @param mixed $calendarId
+     * @param string[] $uris
+     * @return array
+     */
+    function getMultipleCalendarObjects($calendarId, array $uris) {
+        if (empty($uris)) {
+            return [];
+        }
+
+        $chunks = array_chunk($uris, 100);
+        $objects = [];
+
+        $query = $this->db->getQueryBuilder();
+        $query->select(['id', 'uri', 'lastmodified', 'etag', 'calendarid', 'size', 'calendardata', 'componenttype', 'classification'])
+            ->from('calendarobjects')
+            ->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)))
+            ->andWhere($query->expr()->in('uri', $query->createParameter('uri')));
+
+        foreach ($chunks as $uris) {
+            $query->setParameter('uri', $uris, IQueryBuilder::PARAM_STR_ARRAY);
+            $result = $query->execute();
+
+            while ($row = $result->fetch()) {
+                $objects[] = [
+                    'id'           => $row['id'],
+                    'uri'          => $row['uri'],
+                    'lastmodified' => $row['lastmodified'],
+                    'etag'         => '"' . $row['etag'] . '"',
+                    'calendarid'   => $row['calendarid'],
+                    'size'         => (int)$row['size'],
+                    'calendardata' => $this->readBlob($row['calendardata']),
+                    'component'    => strtolower($row['componenttype']),
+                    'classification' => (int)$row['classification']
+                ];
+            }
+            $result->closeCursor();
+        }
+        return $objects;
+    }
+
+    /**
+     * Creates a new calendar object.
+     *
+     * The object uri is only the basename, or filename and not a full path.
+     *
+     * It is possible return an etag from this function, which will be used in
+     * the response to this PUT request. Note that the ETag must be surrounded
+     * by double-quotes.
+     *
+     * However, you should only really return this ETag if you don't mangle the
+     * calendar-data. If the result of a subsequent GET to this object is not
+     * the exact same as this request body, you should omit the ETag.
+     *
+     * @param mixed $calendarId
+     * @param string $objectUri
+     * @param string $calendarData
+     * @return string
+     */
+    function createCalendarObject($calendarId, $objectUri, $calendarData) {
+        $extraData = $this->getDenormalizedData($calendarData);
+
+        $query = $this->db->getQueryBuilder();
+        $query->insert('calendarobjects')
+            ->values([
+                'calendarid' => $query->createNamedParameter($calendarId),
+                'uri' => $query->createNamedParameter($objectUri),
+                'calendardata' => $query->createNamedParameter($calendarData, IQueryBuilder::PARAM_LOB),
+                'lastmodified' => $query->createNamedParameter(time()),
+                'etag' => $query->createNamedParameter($extraData['etag']),
+                'size' => $query->createNamedParameter($extraData['size']),
+                'componenttype' => $query->createNamedParameter($extraData['componentType']),
+                'firstoccurence' => $query->createNamedParameter($extraData['firstOccurence']),
+                'lastoccurence' => $query->createNamedParameter($extraData['lastOccurence']),
+                'classification' => $query->createNamedParameter($extraData['classification']),
+                'uid' => $query->createNamedParameter($extraData['uid']),
+            ])
+            ->execute();
+
+        $this->updateProperties($calendarId, $objectUri, $calendarData);
+
+        $this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::createCalendarObject', new GenericEvent(
+            '\OCA\DAV\CalDAV\CalDavBackend::createCalendarObject',
+            [
+                'calendarId' => $calendarId,
+                'calendarData' => $this->getCalendarById($calendarId),
+                'shares' => $this->getShares($calendarId),
+                'objectData' => $this->getCalendarObject($calendarId, $objectUri),
+            ]
+        ));
+        $this->addChange($calendarId, $objectUri, 1);
+
+        return '"' . $extraData['etag'] . '"';
+    }
+
+    /**
+     * Updates an existing calendarobject, based on it's uri.
+     *
+     * The object uri is only the basename, or filename and not a full path.
+     *
+     * It is possible return an etag from this function, which will be used in
+     * the response to this PUT request. Note that the ETag must be surrounded
+     * by double-quotes.
+     *
+     * However, you should only really return this ETag if you don't mangle the
+     * calendar-data. If the result of a subsequent GET to this object is not
+     * the exact same as this request body, you should omit the ETag.
+     *
+     * @param mixed $calendarId
+     * @param string $objectUri
+     * @param string $calendarData
+     * @return string
+     */
+    function updateCalendarObject($calendarId, $objectUri, $calendarData) {
+        $extraData = $this->getDenormalizedData($calendarData);
+
+        $query = $this->db->getQueryBuilder();
+        $query->update('calendarobjects')
+                ->set('calendardata', $query->createNamedParameter($calendarData, IQueryBuilder::PARAM_LOB))
+                ->set('lastmodified', $query->createNamedParameter(time()))
+                ->set('etag', $query->createNamedParameter($extraData['etag']))
+                ->set('size', $query->createNamedParameter($extraData['size']))
+                ->set('componenttype', $query->createNamedParameter($extraData['componentType']))
+                ->set('firstoccurence', $query->createNamedParameter($extraData['firstOccurence']))
+                ->set('lastoccurence', $query->createNamedParameter($extraData['lastOccurence']))
+                ->set('classification', $query->createNamedParameter($extraData['classification']))
+                ->set('uid', $query->createNamedParameter($extraData['uid']))
+            ->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)))
+            ->andWhere($query->expr()->eq('uri', $query->createNamedParameter($objectUri)))
+            ->execute();
+
+        $this->updateProperties($calendarId, $objectUri, $calendarData);
+
+        $data = $this->getCalendarObject($calendarId, $objectUri);
+        if (is_array($data)) {
+            $this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::updateCalendarObject', new GenericEvent(
+                '\OCA\DAV\CalDAV\CalDavBackend::updateCalendarObject',
+                [
+                    'calendarId' => $calendarId,
+                    'calendarData' => $this->getCalendarById($calendarId),
+                    'shares' => $this->getShares($calendarId),
+                    'objectData' => $data,
+                ]
+            ));
+        }
+        $this->addChange($calendarId, $objectUri, 2);
+
+        return '"' . $extraData['etag'] . '"';
+    }
+
+    /**
+     * @param int $calendarObjectId
+     * @param int $classification
+     */
+    public function setClassification($calendarObjectId, $classification) {
+        if (!in_array($classification, [
+            self::CLASSIFICATION_PUBLIC, self::CLASSIFICATION_PRIVATE, self::CLASSIFICATION_CONFIDENTIAL
+        ])) {
+            throw new \InvalidArgumentException();
+        }
+        $query = $this->db->getQueryBuilder();
+        $query->update('calendarobjects')
+            ->set('classification', $query->createNamedParameter($classification))
+            ->where($query->expr()->eq('id', $query->createNamedParameter($calendarObjectId)))
+            ->execute();
+    }
+
+    /**
+     * Deletes an existing calendar object.
+     *
+     * The object uri is only the basename, or filename and not a full path.
+     *
+     * @param mixed $calendarId
+     * @param string $objectUri
+     * @return void
+     */
+    function deleteCalendarObject($calendarId, $objectUri) {
+        $data = $this->getCalendarObject($calendarId, $objectUri);
+        if (is_array($data)) {
+            $this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::deleteCalendarObject', new GenericEvent(
+                '\OCA\DAV\CalDAV\CalDavBackend::deleteCalendarObject',
+                [
+                    'calendarId' => $calendarId,
+                    'calendarData' => $this->getCalendarById($calendarId),
+                    'shares' => $this->getShares($calendarId),
+                    'objectData' => $data,
+                ]
+            ));
+        }
+
+        $stmt = $this->db->prepare('DELETE FROM `*PREFIX*calendarobjects` WHERE `calendarid` = ? AND `uri` = ?');
+        $stmt->execute([$calendarId, $objectUri]);
+
+        $this->purgeProperties($calendarId, $data['id']);
+
+        $this->addChange($calendarId, $objectUri, 3);
+    }
+
+    /**
+     * Performs a calendar-query on the contents of this calendar.
+     *
+     * The calendar-query is defined in RFC4791 : CalDAV. Using the
+     * calendar-query it is possible for a client to request a specific set of
+     * object, based on contents of iCalendar properties, date-ranges and
+     * iCalendar component types (VTODO, VEVENT).
+     *
+     * This method should just return a list of (relative) urls that match this
+     * query.
+     *
+     * The list of filters are specified as an array. The exact array is
+     * documented by Sabre\CalDAV\CalendarQueryParser.
+     *
+     * Note that it is extremely likely that getCalendarObject for every path
+     * returned from this method will be called almost immediately after. You
+     * may want to anticipate this to speed up these requests.
+     *
+     * This method provides a default implementation, which parses *all* the
+     * iCalendar objects in the specified calendar.
+     *
+     * This default may well be good enough for personal use, and calendars
+     * that aren't very large. But if you anticipate high usage, big calendars
+     * or high loads, you are strongly advised to optimize certain paths.
+     *
+     * The best way to do so is override this method and to optimize
+     * specifically for 'common filters'.
+     *
+     * Requests that are extremely common are:
+     *   * requests for just VEVENTS
+     *   * requests for just VTODO
+     *   * requests with a time-range-filter on either VEVENT or VTODO.
+     *
+     * ..and combinations of these requests. It may not be worth it to try to
+     * handle every possible situation and just rely on the (relatively
+     * easy to use) CalendarQueryValidator to handle the rest.
+     *
+     * Note that especially time-range-filters may be difficult to parse. A
+     * time-range filter specified on a VEVENT must for instance also handle
+     * recurrence rules correctly.
+     * A good example of how to interprete all these filters can also simply
+     * be found in Sabre\CalDAV\CalendarQueryFilter. This class is as correct
+     * as possible, so it gives you a good idea on what type of stuff you need
+     * to think of.
+     *
+     * @param mixed $calendarId
+     * @param array $filters
+     * @return array
+     */
+    function calendarQuery($calendarId, array $filters) {
+        $componentType = null;
+        $requirePostFilter = true;
+        $timeRange = null;
+
+        // if no filters were specified, we don't need to filter after a query
+        if (!$filters['prop-filters'] && !$filters['comp-filters']) {
+            $requirePostFilter = false;
+        }
+
+        // Figuring out if there's a component filter
+        if (count($filters['comp-filters']) > 0 && !$filters['comp-filters'][0]['is-not-defined']) {
+            $componentType = $filters['comp-filters'][0]['name'];
+
+            // Checking if we need post-filters
+            if (!$filters['prop-filters'] && !$filters['comp-filters'][0]['comp-filters'] && !$filters['comp-filters'][0]['time-range'] && !$filters['comp-filters'][0]['prop-filters']) {
+                $requirePostFilter = false;
+            }
+            // There was a time-range filter
+            if ($componentType == 'VEVENT' && isset($filters['comp-filters'][0]['time-range'])) {
+                $timeRange = $filters['comp-filters'][0]['time-range'];
+
+                // If start time OR the end time is not specified, we can do a
+                // 100% accurate mysql query.
+                if (!$filters['prop-filters'] && !$filters['comp-filters'][0]['comp-filters'] && !$filters['comp-filters'][0]['prop-filters'] && (!$timeRange['start'] || !$timeRange['end'])) {
+                    $requirePostFilter = false;
+                }
+            }
+
+        }
+        $columns = ['uri'];
+        if ($requirePostFilter) {
+            $columns = ['uri', 'calendardata'];
+        }
+        $query = $this->db->getQueryBuilder();
+        $query->select($columns)
+            ->from('calendarobjects')
+            ->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)));
+
+        if ($componentType) {
+            $query->andWhere($query->expr()->eq('componenttype', $query->createNamedParameter($componentType)));
+        }
+
+        if ($timeRange && $timeRange['start']) {
+            $query->andWhere($query->expr()->gt('lastoccurence', $query->createNamedParameter($timeRange['start']->getTimeStamp())));
+        }
+        if ($timeRange && $timeRange['end']) {
+            $query->andWhere($query->expr()->lt('firstoccurence', $query->createNamedParameter($timeRange['end']->getTimeStamp())));
+        }
+
+        $stmt = $query->execute();
+
+        $result = [];
+        while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+            if ($requirePostFilter) {
+                if (!$this->validateFilterForObject($row, $filters)) {
+                    continue;
+                }
+            }
+            $result[] = $row['uri'];
+        }
+
+        return $result;
+    }
+
+    /**
+     * custom Nextcloud search extension for CalDAV
+     *
+     * @param string $principalUri
+     * @param array $filters
+     * @param integer|null $limit
+     * @param integer|null $offset
+     * @return array
+     */
+    public function calendarSearch($principalUri, array $filters, $limit=null, $offset=null) {
+        $calendars = $this->getCalendarsForUser($principalUri);
+        $ownCalendars = [];
+        $sharedCalendars = [];
+
+        $uriMapper = [];
+
+        foreach($calendars as $calendar) {
+            if ($calendar['{http://owncloud.org/ns}owner-principal'] === $principalUri) {
+                $ownCalendars[] = $calendar['id'];
+            } else {
+                $sharedCalendars[] = $calendar['id'];
+            }
+            $uriMapper[$calendar['id']] = $calendar['uri'];
+        }
+        if (count($ownCalendars) === 0 && count($sharedCalendars) === 0) {
+            return [];
+        }
+
+        $query = $this->db->getQueryBuilder();
+        // Calendar id expressions
+        $calendarExpressions = [];
+        foreach($ownCalendars as $id) {
+            $calendarExpressions[] = $query->expr()
+                ->eq('c.calendarid', $query->createNamedParameter($id));
+        }
+        foreach($sharedCalendars as $id) {
+            $calendarExpressions[] = $query->expr()->andX(
+                $query->expr()->eq('c.calendarid',
+                    $query->createNamedParameter($id)),
+                $query->expr()->eq('c.classification',
+                    $query->createNamedParameter(self::CLASSIFICATION_PUBLIC))
+            );
+        }
+
+        if (count($calendarExpressions) === 1) {
+            $calExpr = $calendarExpressions[0];
+        } else {
+            $calExpr = call_user_func_array([$query->expr(), 'orX'], $calendarExpressions);
+        }
+
+        // Component expressions
+        $compExpressions = [];
+        foreach($filters['comps'] as $comp) {
+            $compExpressions[] = $query->expr()
+                ->eq('c.componenttype', $query->createNamedParameter($comp));
+        }
+
+        if (count($compExpressions) === 1) {
+            $compExpr = $compExpressions[0];
+        } else {
+            $compExpr = call_user_func_array([$query->expr(), 'orX'], $compExpressions);
+        }
+
+        if (!isset($filters['props'])) {
+            $filters['props'] = [];
+        }
+        if (!isset($filters['params'])) {
+            $filters['params'] = [];
+        }
+
+        $propParamExpressions = [];
+        foreach($filters['props'] as $prop) {
+            $propParamExpressions[] = $query->expr()->andX(
+                $query->expr()->eq('i.name', $query->createNamedParameter($prop)),
+                $query->expr()->isNull('i.parameter')
+            );
+        }
+        foreach($filters['params'] as $param) {
+            $propParamExpressions[] = $query->expr()->andX(
+                $query->expr()->eq('i.name', $query->createNamedParameter($param['property'])),
+                $query->expr()->eq('i.parameter', $query->createNamedParameter($param['parameter']))
+            );
+        }
+
+        if (count($propParamExpressions) === 1) {
+            $propParamExpr = $propParamExpressions[0];
+        } else {
+            $propParamExpr = call_user_func_array([$query->expr(), 'orX'], $propParamExpressions);
+        }
+
+        $query->select(['c.calendarid', 'c.uri'])
+            ->from($this->dbObjectPropertiesTable, 'i')
+            ->join('i', 'calendarobjects', 'c', $query->expr()->eq('i.objectid', 'c.id'))
+            ->where($calExpr)
+            ->andWhere($compExpr)
+            ->andWhere($propParamExpr)
+            ->andWhere($query->expr()->iLike('i.value',
+                $query->createNamedParameter('%'.$this->db->escapeLikeParameter($filters['search-term']).'%')));
+
+        if ($offset) {
+            $query->setFirstResult($offset);
+        }
+        if ($limit) {
+            $query->setMaxResults($limit);
+        }
+
+        $stmt = $query->execute();
+
+        $result = [];
+        while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+            $path = $uriMapper[$row['calendarid']] . '/' . $row['uri'];
+            if (!in_array($path, $result)) {
+                $result[] = $path;
+            }
+        }
+
+        return $result;
+    }
+
+    /**
+     * Searches through all of a users calendars and calendar objects to find
+     * an object with a specific UID.
+     *
+     * This method should return the path to this object, relative to the
+     * calendar home, so this path usually only contains two parts:
+     *
+     * calendarpath/objectpath.ics
+     *
+     * If the uid is not found, return null.
+     *
+     * This method should only consider * objects that the principal owns, so
+     * any calendars owned by other principals that also appear in this
+     * collection should be ignored.
+     *
+     * @param string $principalUri
+     * @param string $uid
+     * @return string|null
+     */
+    function getCalendarObjectByUID($principalUri, $uid) {
+
+        $query = $this->db->getQueryBuilder();
+        $query->selectAlias('c.uri', 'calendaruri')->selectAlias('co.uri', 'objecturi')
+            ->from('calendarobjects', 'co')
+            ->leftJoin('co', 'calendars', 'c', $query->expr()->eq('co.calendarid', 'c.id'))
+            ->where($query->expr()->eq('c.principaluri', $query->createNamedParameter($principalUri)))
+            ->andWhere($query->expr()->eq('co.uid', $query->createNamedParameter($uid)));
+
+        $stmt = $query->execute();
+
+        if ($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+            return $row['calendaruri'] . '/' . $row['objecturi'];
+        }
+
+        return null;
+    }
+
+    /**
+     * The getChanges method returns all the changes that have happened, since
+     * the specified syncToken in the specified calendar.
+     *
+     * This function should return an array, such as the following:
+     *
+     * [
+     *   'syncToken' => 'The current synctoken',
+     *   'added'   => [
+     *      'new.txt',
+     *   ],
+     *   'modified'   => [
+     *      'modified.txt',
+     *   ],
+     *   'deleted' => [
+     *      'foo.php.bak',
+     *      'old.txt'
+     *   ]
+     * );
+     *
+     * The returned syncToken property should reflect the *current* syncToken
+     * of the calendar, as reported in the {http://sabredav.org/ns}sync-token
+     * property This is * needed here too, to ensure the operation is atomic.
+     *
+     * If the $syncToken argument is specified as null, this is an initial
+     * sync, and all members should be reported.
+     *
+     * The modified property is an array of nodenames that have changed since
+     * the last token.
+     *
+     * The deleted property is an array with nodenames, that have been deleted
+     * from collection.
+     *
+     * The $syncLevel argument is basically the 'depth' of the report. If it's
+     * 1, you only have to report changes that happened only directly in
+     * immediate descendants. If it's 2, it should also include changes from
+     * the nodes below the child collections. (grandchildren)
+     *
+     * The $limit argument allows a client to specify how many results should
+     * be returned at most. If the limit is not specified, it should be treated
+     * as infinite.
+     *
+     * If the limit (infinite or not) is higher than you're willing to return,
+     * you should throw a Sabre\DAV\Exception\TooMuchMatches() exception.
+     *
+     * If the syncToken is expired (due to data cleanup) or unknown, you must
+     * return null.
+     *
+     * The limit is 'suggestive'. You are free to ignore it.
+     *
+     * @param string $calendarId
+     * @param string $syncToken
+     * @param int $syncLevel
+     * @param int $limit
+     * @return array
+     */
+    function getChangesForCalendar($calendarId, $syncToken, $syncLevel, $limit = null) {
+        // Current synctoken
+        $stmt = $this->db->prepare('SELECT `synctoken` FROM `*PREFIX*calendars` WHERE `id` = ?');
+        $stmt->execute([ $calendarId ]);
+        $currentToken = $stmt->fetchColumn(0);
+
+        if (is_null($currentToken)) {
+            return null;
+        }
+
+        $result = [
+            'syncToken' => $currentToken,
+            'added'     => [],
+            'modified'  => [],
+            'deleted'   => [],
+        ];
+
+        if ($syncToken) {
+
+            $query = "SELECT `uri`, `operation` FROM `*PREFIX*calendarchanges` WHERE `synctoken` >= ? AND `synctoken` < ? AND `calendarid` = ? ORDER BY `synctoken`";
+            if ($limit>0) {
+                $query.= " `LIMIT` " . (int)$limit;
+            }
+
+            // Fetching all changes
+            $stmt = $this->db->prepare($query);
+            $stmt->execute([$syncToken, $currentToken, $calendarId]);
+
+            $changes = [];
+
+            // This loop ensures that any duplicates are overwritten, only the
+            // last change on a node is relevant.
+            while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+
+                $changes[$row['uri']] = $row['operation'];
+
+            }
+
+            foreach($changes as $uri => $operation) {
+
+                switch($operation) {
+                    case 1 :
+                        $result['added'][] = $uri;
+                        break;
+                    case 2 :
+                        $result['modified'][] = $uri;
+                        break;
+                    case 3 :
+                        $result['deleted'][] = $uri;
+                        break;
+                }
+
+            }
+        } else {
+            // No synctoken supplied, this is the initial sync.
+            $query = "SELECT `uri` FROM `*PREFIX*calendarobjects` WHERE `calendarid` = ?";
+            $stmt = $this->db->prepare($query);
+            $stmt->execute([$calendarId]);
+
+            $result['added'] = $stmt->fetchAll(\PDO::FETCH_COLUMN);
+        }
+        return $result;
+
+    }
+
+    /**
+     * Returns a list of subscriptions for a principal.
+     *
+     * Every subscription is an array with the following keys:
+     *  * id, a unique id that will be used by other functions to modify the
+     *    subscription. This can be the same as the uri or a database key.
+     *  * uri. This is just the 'base uri' or 'filename' of the subscription.
+     *  * principaluri. The owner of the subscription. Almost always the same as
+     *    principalUri passed to this method.
+     *
+     * Furthermore, all the subscription info must be returned too:
+     *
+     * 1. {DAV:}displayname
+     * 2. {http://apple.com/ns/ical/}refreshrate
+     * 3. {http://calendarserver.org/ns/}subscribed-strip-todos (omit if todos
+     *    should not be stripped).
+     * 4. {http://calendarserver.org/ns/}subscribed-strip-alarms (omit if alarms
+     *    should not be stripped).
+     * 5. {http://calendarserver.org/ns/}subscribed-strip-attachments (omit if
+     *    attachments should not be stripped).
+     * 6. {http://calendarserver.org/ns/}source (Must be a
+     *     Sabre\DAV\Property\Href).
+     * 7. {http://apple.com/ns/ical/}calendar-color
+     * 8. {http://apple.com/ns/ical/}calendar-order
+     * 9. {urn:ietf:params:xml:ns:caldav}supported-calendar-component-set
+     *    (should just be an instance of
+     *    Sabre\CalDAV\Property\SupportedCalendarComponentSet, with a bunch of
+     *    default components).
+     *
+     * @param string $principalUri
+     * @return array
+     */
+    function getSubscriptionsForUser($principalUri) {
+        $fields = array_values($this->subscriptionPropertyMap);
+        $fields[] = 'id';
+        $fields[] = 'uri';
+        $fields[] = 'source';
+        $fields[] = 'principaluri';
+        $fields[] = 'lastmodified';
+
+        $query = $this->db->getQueryBuilder();
+        $query->select($fields)
+            ->from('calendarsubscriptions')
+            ->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
+            ->orderBy('calendarorder', 'asc');
+        $stmt =$query->execute();
+
+        $subscriptions = [];
+        while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+
+            $subscription = [
+                'id'           => $row['id'],
+                'uri'          => $row['uri'],
+                'principaluri' => $row['principaluri'],
+                'source'       => $row['source'],
+                'lastmodified' => $row['lastmodified'],
+
+                '{' . Plugin::NS_CALDAV . '}supported-calendar-component-set' => new SupportedCalendarComponentSet(['VTODO', 'VEVENT']),
+            ];
+
+            foreach($this->subscriptionPropertyMap as $xmlName=>$dbName) {
+                if (!is_null($row[$dbName])) {
+                    $subscription[$xmlName] = $row[$dbName];
+                }
+            }
+
+            $subscriptions[] = $subscription;
+
+        }
+
+        return $subscriptions;
+    }
+
+    /**
+     * Creates a new subscription for a principal.
+     *
+     * If the creation was a success, an id must be returned that can be used to reference
+     * this subscription in other methods, such as updateSubscription.
+     *
+     * @param string $principalUri
+     * @param string $uri
+     * @param array $properties
+     * @return mixed
+     */
+    function createSubscription($principalUri, $uri, array $properties) {
+
+        if (!isset($properties['{http://calendarserver.org/ns/}source'])) {
+            throw new Forbidden('The {http://calendarserver.org/ns/}source property is required when creating subscriptions');
+        }
+
+        $values = [
+            'principaluri' => $principalUri,
+            'uri'          => $uri,
+            'source'       => $properties['{http://calendarserver.org/ns/}source']->getHref(),
+            'lastmodified' => time(),
+        ];
+
+        $propertiesBoolean = ['striptodos', 'stripalarms', 'stripattachments'];
+
+        foreach($this->subscriptionPropertyMap as $xmlName=>$dbName) {
+            if (array_key_exists($xmlName, $properties)) {
+                    $values[$dbName] = $properties[$xmlName];
+                    if (in_array($dbName, $propertiesBoolean)) {
+                        $values[$dbName] = true;
+                }
+            }
+        }
+
+        $valuesToInsert = array();
+
+        $query = $this->db->getQueryBuilder();
+
+        foreach (array_keys($values) as $name) {
+            $valuesToInsert[$name] = $query->createNamedParameter($values[$name]);
+        }
+
+        $query->insert('calendarsubscriptions')
+            ->values($valuesToInsert)
+            ->execute();
+
+        return $this->db->lastInsertId('*PREFIX*calendarsubscriptions');
+    }
+
+    /**
+     * Updates a subscription
+     *
+     * The list of mutations is stored in a Sabre\DAV\PropPatch object.
+     * To do the actual updates, you must tell this object which properties
+     * you're going to process with the handle() method.
+     *
+     * Calling the handle method is like telling the PropPatch object "I
+     * promise I can handle updating this property".
+     *
+     * Read the PropPatch documentation for more info and examples.
+     *
+     * @param mixed $subscriptionId
+     * @param PropPatch $propPatch
+     * @return void
+     */
+    function updateSubscription($subscriptionId, PropPatch $propPatch) {
+        $supportedProperties = array_keys($this->subscriptionPropertyMap);
+        $supportedProperties[] = '{http://calendarserver.org/ns/}source';
+
+        $propPatch->handle($supportedProperties, function($mutations) use ($subscriptionId) {
+
+            $newValues = [];
+
+            foreach($mutations as $propertyName=>$propertyValue) {
+                if ($propertyName === '{http://calendarserver.org/ns/}source') {
+                    $newValues['source'] = $propertyValue->getHref();
+                } else {
+                    $fieldName = $this->subscriptionPropertyMap[$propertyName];
+                    $newValues[$fieldName] = $propertyValue;
+                }
+            }
+
+            $query = $this->db->getQueryBuilder();
+            $query->update('calendarsubscriptions')
+                ->set('lastmodified', $query->createNamedParameter(time()));
+            foreach($newValues as $fieldName=>$value) {
+                $query->set($fieldName, $query->createNamedParameter($value));
+            }
+            $query->where($query->expr()->eq('id', $query->createNamedParameter($subscriptionId)))
+                ->execute();
+
+            return true;
+
+        });
+    }
+
+    /**
+     * Deletes a subscription.
+     *
+     * @param mixed $subscriptionId
+     * @return void
+     */
+    function deleteSubscription($subscriptionId) {
+        $query = $this->db->getQueryBuilder();
+        $query->delete('calendarsubscriptions')
+            ->where($query->expr()->eq('id', $query->createNamedParameter($subscriptionId)))
+            ->execute();
+    }
+
+    /**
+     * Returns a single scheduling object for the inbox collection.
+     *
+     * The returned array should contain the following elements:
+     *   * uri - A unique basename for the object. This will be used to
+     *           construct a full uri.
+     *   * calendardata - The iCalendar object
+     *   * lastmodified - The last modification date. Can be an int for a unix
+     *                    timestamp, or a PHP DateTime object.
+     *   * etag - A unique token that must change if the object changed.
+     *   * size - The size of the object, in bytes.
+     *
+     * @param string $principalUri
+     * @param string $objectUri
+     * @return array
+     */
+    function getSchedulingObject($principalUri, $objectUri) {
+        $query = $this->db->getQueryBuilder();
+        $stmt = $query->select(['uri', 'calendardata', 'lastmodified', 'etag', 'size'])
+            ->from('schedulingobjects')
+            ->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
+            ->andWhere($query->expr()->eq('uri', $query->createNamedParameter($objectUri)))
+            ->execute();
+
+        $row = $stmt->fetch(\PDO::FETCH_ASSOC);
+
+        if(!$row) {
+            return null;
+        }
+
+        return [
+                'uri'          => $row['uri'],
+                'calendardata' => $row['calendardata'],
+                'lastmodified' => $row['lastmodified'],
+                'etag'         => '"' . $row['etag'] . '"',
+                'size'         => (int)$row['size'],
+        ];
+    }
+
+    /**
+     * Returns all scheduling objects for the inbox collection.
+     *
+     * These objects should be returned as an array. Every item in the array
+     * should follow the same structure as returned from getSchedulingObject.
+     *
+     * The main difference is that 'calendardata' is optional.
+     *
+     * @param string $principalUri
+     * @return array
+     */
+    function getSchedulingObjects($principalUri) {
+        $query = $this->db->getQueryBuilder();
+        $stmt = $query->select(['uri', 'calendardata', 'lastmodified', 'etag', 'size'])
+                ->from('schedulingobjects')
+                ->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
+                ->execute();
+
+        $result = [];
+        foreach($stmt->fetchAll(\PDO::FETCH_ASSOC) as $row) {
+            $result[] = [
+                    'calendardata' => $row['calendardata'],
+                    'uri'          => $row['uri'],
+                    'lastmodified' => $row['lastmodified'],
+                    'etag'         => '"' . $row['etag'] . '"',
+                    'size'         => (int)$row['size'],
+            ];
+        }
+
+        return $result;
+    }
+
+    /**
+     * Deletes a scheduling object from the inbox collection.
+     *
+     * @param string $principalUri
+     * @param string $objectUri
+     * @return void
+     */
+    function deleteSchedulingObject($principalUri, $objectUri) {
+        $query = $this->db->getQueryBuilder();
+        $query->delete('schedulingobjects')
+                ->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)))
+                ->andWhere($query->expr()->eq('uri', $query->createNamedParameter($objectUri)))
+                ->execute();
+    }
+
+    /**
+     * Creates a new scheduling object. This should land in a users' inbox.
+     *
+     * @param string $principalUri
+     * @param string $objectUri
+     * @param string $objectData
+     * @return void
+     */
+    function createSchedulingObject($principalUri, $objectUri, $objectData) {
+        $query = $this->db->getQueryBuilder();
+        $query->insert('schedulingobjects')
+            ->values([
+                'principaluri' => $query->createNamedParameter($principalUri),
+                'calendardata' => $query->createNamedParameter($objectData),
+                'uri' => $query->createNamedParameter($objectUri),
+                'lastmodified' => $query->createNamedParameter(time()),
+                'etag' => $query->createNamedParameter(md5($objectData)),
+                'size' => $query->createNamedParameter(strlen($objectData))
+            ])
+            ->execute();
+    }
+
+    /**
+     * Adds a change record to the calendarchanges table.
+     *
+     * @param mixed $calendarId
+     * @param string $objectUri
+     * @param int $operation 1 = add, 2 = modify, 3 = delete.
+     * @return void
+     */
+    protected function addChange($calendarId, $objectUri, $operation) {
+
+        $stmt = $this->db->prepare('INSERT INTO `*PREFIX*calendarchanges` (`uri`, `synctoken`, `calendarid`, `operation`) SELECT ?, `synctoken`, ?, ? FROM `*PREFIX*calendars` WHERE `id` = ?');
+        $stmt->execute([
+            $objectUri,
+            $calendarId,
+            $operation,
+            $calendarId
+        ]);
+        $stmt = $this->db->prepare('UPDATE `*PREFIX*calendars` SET `synctoken` = `synctoken` + 1 WHERE `id` = ?');
+        $stmt->execute([
+            $calendarId
+        ]);
+
+    }
+
+    /**
+     * Parses some information from calendar objects, used for optimized
+     * calendar-queries.
+     *
+     * Returns an array with the following keys:
+     *   * etag - An md5 checksum of the object without the quotes.
+     *   * size - Size of the object in bytes
+     *   * componentType - VEVENT, VTODO or VJOURNAL
+     *   * firstOccurence
+     *   * lastOccurence
+     *   * uid - value of the UID property
+     *
+     * @param string $calendarData
+     * @return array
+     */
+    public function getDenormalizedData($calendarData) {
+
+        $vObject = Reader::read($calendarData);
+        $componentType = null;
+        $component = null;
+        $firstOccurrence = null;
+        $lastOccurrence = null;
+        $uid = null;
+        $classification = self::CLASSIFICATION_PUBLIC;
+        foreach($vObject->getComponents() as $component) {
+            if ($component->name!=='VTIMEZONE') {
+                $componentType = $component->name;
+                $uid = (string)$component->UID;
+                break;
+            }
+        }
+        if (!$componentType) {
+            throw new \Sabre\DAV\Exception\BadRequest('Calendar objects must have a VJOURNAL, VEVENT or VTODO component');
+        }
+        if ($componentType === 'VEVENT' && $component->DTSTART) {
+            $firstOccurrence = $component->DTSTART->getDateTime()->getTimeStamp();
+            // Finding the last occurrence is a bit harder
+            if (!isset($component->RRULE)) {
+                if (isset($component->DTEND)) {
+                    $lastOccurrence = $component->DTEND->getDateTime()->getTimeStamp();
+                } elseif (isset($component->DURATION)) {
+                    $endDate = clone $component->DTSTART->getDateTime();
+                    $endDate->add(DateTimeParser::parse($component->DURATION->getValue()));
+                    $lastOccurrence = $endDate->getTimeStamp();
+                } elseif (!$component->DTSTART->hasTime()) {
+                    $endDate = clone $component->DTSTART->getDateTime();
+                    $endDate->modify('+1 day');
+                    $lastOccurrence = $endDate->getTimeStamp();
+                } else {
+                    $lastOccurrence = $firstOccurrence;
+                }
+            } else {
+                $it = new EventIterator($vObject, (string)$component->UID);
+                $maxDate = new \DateTime(self::MAX_DATE);
+                if ($it->isInfinite()) {
+                    $lastOccurrence = $maxDate->getTimestamp();
+                } else {
+                    $end = $it->getDtEnd();
+                    while($it->valid() && $end < $maxDate) {
+                        $end = $it->getDtEnd();
+                        $it->next();
+
+                    }
+                    $lastOccurrence = $end->getTimestamp();
+                }
+
+            }
+        }
+
+        if ($component->CLASS) {
+            $classification = CalDavBackend::CLASSIFICATION_PRIVATE;
+            switch ($component->CLASS->getValue()) {
+                case 'PUBLIC':
+                    $classification = CalDavBackend::CLASSIFICATION_PUBLIC;
+                    break;
+                case 'CONFIDENTIAL':
+                    $classification = CalDavBackend::CLASSIFICATION_CONFIDENTIAL;
+                    break;
+            }
+        }
+        return [
+            'etag' => md5($calendarData),
+            'size' => strlen($calendarData),
+            'componentType' => $componentType,
+            'firstOccurence' => is_null($firstOccurrence) ? null : max(0, $firstOccurrence),
+            'lastOccurence'  => $lastOccurrence,
+            'uid' => $uid,
+            'classification' => $classification
+        ];
+
+    }
+
+    private function readBlob($cardData) {
+        if (is_resource($cardData)) {
+            return stream_get_contents($cardData);
+        }
+
+        return $cardData;
+    }
+
+    /**
+     * @param IShareable $shareable
+     * @param array $add
+     * @param array $remove
+     */
+    public function updateShares($shareable, $add, $remove) {
+        $calendarId = $shareable->getResourceId();
+        $this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::updateShares', new GenericEvent(
+            '\OCA\DAV\CalDAV\CalDavBackend::updateShares',
+            [
+                'calendarId' => $calendarId,
+                'calendarData' => $this->getCalendarById($calendarId),
+                'shares' => $this->getShares($calendarId),
+                'add' => $add,
+                'remove' => $remove,
+            ]));
+        $this->sharingBackend->updateShares($shareable, $add, $remove);
+    }
+
+    /**
+     * @param int $resourceId
+     * @return array
+     */
+    public function getShares($resourceId) {
+        return $this->sharingBackend->getShares($resourceId);
+    }
+
+    /**
+     * @param boolean $value
+     * @param \OCA\DAV\CalDAV\Calendar $calendar
+     * @return string|null
+     */
+    public function setPublishStatus($value, $calendar) {
+        $query = $this->db->getQueryBuilder();
+        if ($value) {
+            $publicUri = $this->random->generate(16, ISecureRandom::CHAR_HUMAN_READABLE);
+            $query->insert('dav_shares')
+                ->values([
+                    'principaluri' => $query->createNamedParameter($calendar->getPrincipalURI()),
+                    'type' => $query->createNamedParameter('calendar'),
+                    'access' => $query->createNamedParameter(self::ACCESS_PUBLIC),
+                    'resourceid' => $query->createNamedParameter($calendar->getResourceId()),
+                    'publicuri' => $query->createNamedParameter($publicUri)
+                ]);
+            $query->execute();
+            return $publicUri;
+        }
+        $query->delete('dav_shares')
+            ->where($query->expr()->eq('resourceid', $query->createNamedParameter($calendar->getResourceId())))
+            ->andWhere($query->expr()->eq('access', $query->createNamedParameter(self::ACCESS_PUBLIC)));
+        $query->execute();
+        return null;
+    }
+
+    /**
+     * @param \OCA\DAV\CalDAV\Calendar $calendar
+     * @return mixed
+     */
+    public function getPublishStatus($calendar) {
+        $query = $this->db->getQueryBuilder();
+        $result = $query->select('publicuri')
+            ->from('dav_shares')
+            ->where($query->expr()->eq('resourceid', $query->createNamedParameter($calendar->getResourceId())))
+            ->andWhere($query->expr()->eq('access', $query->createNamedParameter(self::ACCESS_PUBLIC)))
+            ->execute();
+
+        $row = $result->fetch();
+        $result->closeCursor();
+        return $row ? reset($row) : false;
+    }
+
+    /**
+     * @param int $resourceId
+     * @param array $acl
+     * @return array
+     */
+    public function applyShareAcl($resourceId, $acl) {
+        return $this->sharingBackend->applyShareAcl($resourceId, $acl);
+    }
+
+
+
+    /**
+     * update properties table
+     *
+     * @param int $calendarId
+     * @param string $objectUri
+     * @param string $calendarData
+     */
+    public function updateProperties($calendarId, $objectUri, $calendarData) {
+        $objectId = $this->getCalendarObjectId($calendarId, $objectUri);
+
+        try {
+            $vCalendar = $this->readCalendarData($calendarData);
+        } catch (\Exception $ex) {
+            return;
+        }
+
+        $this->purgeProperties($calendarId, $objectId);
+
+        $query = $this->db->getQueryBuilder();
+        $query->insert($this->dbObjectPropertiesTable)
+            ->values(
+                [
+                    'calendarid' => $query->createNamedParameter($calendarId),
+                    'objectid' => $query->createNamedParameter($objectId),
+                    'name' => $query->createParameter('name'),
+                    'parameter' => $query->createParameter('parameter'),
+                    'value' => $query->createParameter('value'),
+                ]
+            );
+
+        $indexComponents = ['VEVENT', 'VJOURNAL', 'VTODO'];
+        foreach ($vCalendar->getComponents() as $component) {
+            if (!in_array($component->name, $indexComponents)) {
+                continue;
+            }
+
+            foreach ($component->children() as $property) {
+                if (in_array($property->name, self::$indexProperties)) {
+                    $value = $property->getValue();
+                    // is this a shitty db?
+                    if (!$this->db->supports4ByteText()) {
+                        $value = preg_replace('/[\x{10000}-\x{10FFFF}]/u', "\xEF\xBF\xBD", $value);
+                    }
+                    $value = substr($value, 0, 254);
+
+                    $query->setParameter('name', $property->name);
+                    $query->setParameter('parameter', null);
+                    $query->setParameter('value', $value);
+                    $query->execute();
+                }
+
+                if (in_array($property->name, array_keys(self::$indexParameters))) {
+                    $parameters = $property->parameters();
+                    $indexedParametersForProperty = self::$indexParameters[$property->name];
+
+                    foreach ($parameters as $key => $value) {
+                        if (in_array($key, $indexedParametersForProperty)) {
+                            // is this a shitty db?
+                            if ($this->db->supports4ByteText()) {
+                                $value = preg_replace('/[\x{10000}-\x{10FFFF}]/u', "\xEF\xBF\xBD", $value);
+                            }
+                            $value = substr($value, 0, 254);
+
+                            $query->setParameter('name', $property->name);
+                            $query->setParameter('parameter', substr($key, 0, 254));
+                            $query->setParameter('value', substr($value, 0, 254));
+                            $query->execute();
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    /**
+     * read VCalendar data into a VCalendar object
+     *
+     * @param string $objectData
+     * @return VCalendar
+     */
+    protected function readCalendarData($objectData) {
+        return Reader::read($objectData);
+    }
+
+    /**
+     * delete all properties from a given calendar object
+     *
+     * @param int $calendarId
+     * @param int $objectId
+     */
+    protected function purgeProperties($calendarId, $objectId) {
+        $query = $this->db->getQueryBuilder();
+        $query->delete($this->dbObjectPropertiesTable)
+            ->where($query->expr()->eq('objectid', $query->createNamedParameter($objectId)))
+            ->andWhere($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)));
+        $query->execute();
+    }
+
+    /**
+     * get ID from a given calendar object
+     *
+     * @param int $calendarId
+     * @param string $uri
+     * @return int
+     */
+    protected function getCalendarObjectId($calendarId, $uri) {
+        $query = $this->db->getQueryBuilder();
+        $query->select('id')->from('calendarobjects')
+            ->where($query->expr()->eq('uri', $query->createNamedParameter($uri)))
+            ->andWhere($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)));
+
+        $result = $query->execute();
+        $objectIds = $result->fetch();
+        $result->closeCursor();
+
+        if (!isset($objectIds['id'])) {
+            throw new \InvalidArgumentException('Calendarobject does not exists: ' . $uri);
+        }
+
+        return (int)$objectIds['id'];
+    }
+
+    private function convertPrincipal($principalUri, $toV2) {
+        if ($this->principalBackend->getPrincipalPrefix() === 'principals') {
+            list(, $name) = URLUtil::splitPath($principalUri);
+            if ($toV2 === true) {
+                return "principals/users/$name";
+            }
+            return "principals/$name";
+        }
+        return $principalUri;
+    }
+
+    private function addOwnerPrincipal(&$calendarInfo) {
+        $ownerPrincipalKey = '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD . '}owner-principal';
+        $displaynameKey = '{' . \OCA\DAV\DAV\Sharing\Plugin::NS_NEXTCLOUD . '}owner-displayname';
+        if (isset($calendarInfo[$ownerPrincipalKey])) {
+            $uri = $calendarInfo[$ownerPrincipalKey];
+        } else {
+            $uri = $calendarInfo['principaluri'];
+        }
+
+        $principalInformation = $this->principalBackend->getPrincipalByPath($uri);
+        if (isset($principalInformation['{DAV:}displayname'])) {
+            $calendarInfo[$displaynameKey] = $principalInformation['{DAV:}displayname'];
+        }
+    }
 }

lib/private/Share20/Manager.php

Indentation +1360 added lines, -1360 removed lines

@@ -56,1388 +56,1388 @@
  */
 class Manager implements IManager {
 
-	/** @var IProviderFactory */
-	private $factory;
-	/** @var ILogger */
-	private $logger;
-	/** @var IConfig */
-	private $config;
-	/** @var ISecureRandom */
-	private $secureRandom;
-	/** @var IHasher */
-	private $hasher;
-	/** @var IMountManager */
-	private $mountManager;
-	/** @var IGroupManager */
-	private $groupManager;
-	/** @var IL10N */
-	private $l;
-	/** @var IUserManager */
-	private $userManager;
-	/** @var IRootFolder */
-	private $rootFolder;
-	/** @var CappedMemoryCache */
-	private $sharingDisabledForUsersCache;
-	/** @var EventDispatcher */
-	private $eventDispatcher;
-	/** @var LegacyHooks */
-	private $legacyHooks;
-
-
-	/**
-	 * Manager constructor.
-	 *
-	 * @param ILogger $logger
-	 * @param IConfig $config
-	 * @param ISecureRandom $secureRandom
-	 * @param IHasher $hasher
-	 * @param IMountManager $mountManager
-	 * @param IGroupManager $groupManager
-	 * @param IL10N $l
-	 * @param IProviderFactory $factory
-	 * @param IUserManager $userManager
-	 * @param IRootFolder $rootFolder
-	 * @param EventDispatcher $eventDispatcher
-	 */
-	public function __construct(
-			ILogger $logger,
-			IConfig $config,
-			ISecureRandom $secureRandom,
-			IHasher $hasher,
-			IMountManager $mountManager,
-			IGroupManager $groupManager,
-			IL10N $l,
-			IProviderFactory $factory,
-			IUserManager $userManager,
-			IRootFolder $rootFolder,
-			EventDispatcher $eventDispatcher
-	) {
-		$this->logger = $logger;
-		$this->config = $config;
-		$this->secureRandom = $secureRandom;
-		$this->hasher = $hasher;
-		$this->mountManager = $mountManager;
-		$this->groupManager = $groupManager;
-		$this->l = $l;
-		$this->factory = $factory;
-		$this->userManager = $userManager;
-		$this->rootFolder = $rootFolder;
-		$this->eventDispatcher = $eventDispatcher;
-		$this->sharingDisabledForUsersCache = new CappedMemoryCache();
-		$this->legacyHooks = new LegacyHooks($this->eventDispatcher);
-	}
-
-	/**
-	 * Convert from a full share id to a tuple (providerId, shareId)
-	 *
-	 * @param string $id
-	 * @return string[]
-	 */
-	private function splitFullId($id) {
-		return explode(':', $id, 2);
-	}
-
-	/**
-	 * Verify if a password meets all requirements
-	 *
-	 * @param string $password
-	 * @throws \Exception
-	 */
-	protected function verifyPassword($password) {
-		if ($password === null) {
-			// No password is set, check if this is allowed.
-			if ($this->shareApiLinkEnforcePassword()) {
-				throw new \InvalidArgumentException('Passwords are enforced for link shares');
-			}
-
-			return;
-		}
-
-		// Let others verify the password
-		try {
-			$event = new GenericEvent($password);
-			$this->eventDispatcher->dispatch('OCP\PasswordPolicy::validate', $event);
-		} catch (HintException $e) {
-			throw new \Exception($e->getHint());
-		}
-	}
-
-	/**
-	 * Check for generic requirements before creating a share
-	 *
-	 * @param \OCP\Share\IShare $share
-	 * @throws \InvalidArgumentException
-	 * @throws GenericShareException
-	 *
-	 * @suppress PhanUndeclaredClassMethod
-	 */
-	protected function generalCreateChecks(\OCP\Share\IShare $share) {
-		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER) {
-			// We expect a valid user as sharedWith for user shares
-			if (!$this->userManager->userExists($share->getSharedWith())) {
-				throw new \InvalidArgumentException('SharedWith is not a valid user');
-			}
-		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_GROUP) {
-			// We expect a valid group as sharedWith for group shares
-			if (!$this->groupManager->groupExists($share->getSharedWith())) {
-				throw new \InvalidArgumentException('SharedWith is not a valid group');
-			}
-		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK) {
-			if ($share->getSharedWith() !== null) {
-				throw new \InvalidArgumentException('SharedWith should be empty');
-			}
-		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_REMOTE) {
-			if ($share->getSharedWith() === null) {
-				throw new \InvalidArgumentException('SharedWith should not be empty');
-			}
-		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_EMAIL) {
-			if ($share->getSharedWith() === null) {
-				throw new \InvalidArgumentException('SharedWith should not be empty');
-			}
-		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_CIRCLE) {
-			$circle = \OCA\Circles\Api\v1\Circles::detailsCircle($share->getSharedWith());
-			if ($circle === null) {
-				throw new \InvalidArgumentException('SharedWith is not a valid circle');
-			}
-		} else {
-			// We can't handle other types yet
-			throw new \InvalidArgumentException('unknown share type');
-		}
-
-		// Verify the initiator of the share is set
-		if ($share->getSharedBy() === null) {
-			throw new \InvalidArgumentException('SharedBy should be set');
-		}
-
-		// Cannot share with yourself
-		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER &&
-			$share->getSharedWith() === $share->getSharedBy()) {
-			throw new \InvalidArgumentException('Can’t share with yourself');
-		}
-
-		// The path should be set
-		if ($share->getNode() === null) {
-			throw new \InvalidArgumentException('Path should be set');
-		}
-
-		// And it should be a file or a folder
-		if (!($share->getNode() instanceof \OCP\Files\File) &&
-				!($share->getNode() instanceof \OCP\Files\Folder)) {
-			throw new \InvalidArgumentException('Path should be either a file or a folder');
-		}
-
-		// And you can't share your rootfolder
-		if ($this->userManager->userExists($share->getSharedBy())) {
-			$sharedPath = $this->rootFolder->getUserFolder($share->getSharedBy())->getPath();
-		} else {
-			$sharedPath = $this->rootFolder->getUserFolder($share->getShareOwner())->getPath();
-		}
-		if ($sharedPath === $share->getNode()->getPath()) {
-			throw new \InvalidArgumentException('You can’t share your root folder');
-		}
-
-		// Check if we actually have share permissions
-		if (!$share->getNode()->isShareable()) {
-			$message_t = $this->l->t('You are not allowed to share %s', [$share->getNode()->getPath()]);
-			throw new GenericShareException($message_t, $message_t, 404);
-		}
-
-		// Permissions should be set
-		if ($share->getPermissions() === null) {
-			throw new \InvalidArgumentException('A share requires permissions');
-		}
-
-		/*
+    /** @var IProviderFactory */
+    private $factory;
+    /** @var ILogger */
+    private $logger;
+    /** @var IConfig */
+    private $config;
+    /** @var ISecureRandom */
+    private $secureRandom;
+    /** @var IHasher */
+    private $hasher;
+    /** @var IMountManager */
+    private $mountManager;
+    /** @var IGroupManager */
+    private $groupManager;
+    /** @var IL10N */
+    private $l;
+    /** @var IUserManager */
+    private $userManager;
+    /** @var IRootFolder */
+    private $rootFolder;
+    /** @var CappedMemoryCache */
+    private $sharingDisabledForUsersCache;
+    /** @var EventDispatcher */
+    private $eventDispatcher;
+    /** @var LegacyHooks */
+    private $legacyHooks;
+
+
+    /**
+     * Manager constructor.
+     *
+     * @param ILogger $logger
+     * @param IConfig $config
+     * @param ISecureRandom $secureRandom
+     * @param IHasher $hasher
+     * @param IMountManager $mountManager
+     * @param IGroupManager $groupManager
+     * @param IL10N $l
+     * @param IProviderFactory $factory
+     * @param IUserManager $userManager
+     * @param IRootFolder $rootFolder
+     * @param EventDispatcher $eventDispatcher
+     */
+    public function __construct(
+            ILogger $logger,
+            IConfig $config,
+            ISecureRandom $secureRandom,
+            IHasher $hasher,
+            IMountManager $mountManager,
+            IGroupManager $groupManager,
+            IL10N $l,
+            IProviderFactory $factory,
+            IUserManager $userManager,
+            IRootFolder $rootFolder,
+            EventDispatcher $eventDispatcher
+    ) {
+        $this->logger = $logger;
+        $this->config = $config;
+        $this->secureRandom = $secureRandom;
+        $this->hasher = $hasher;
+        $this->mountManager = $mountManager;
+        $this->groupManager = $groupManager;
+        $this->l = $l;
+        $this->factory = $factory;
+        $this->userManager = $userManager;
+        $this->rootFolder = $rootFolder;
+        $this->eventDispatcher = $eventDispatcher;
+        $this->sharingDisabledForUsersCache = new CappedMemoryCache();
+        $this->legacyHooks = new LegacyHooks($this->eventDispatcher);
+    }
+
+    /**
+     * Convert from a full share id to a tuple (providerId, shareId)
+     *
+     * @param string $id
+     * @return string[]
+     */
+    private function splitFullId($id) {
+        return explode(':', $id, 2);
+    }
+
+    /**
+     * Verify if a password meets all requirements
+     *
+     * @param string $password
+     * @throws \Exception
+     */
+    protected function verifyPassword($password) {
+        if ($password === null) {
+            // No password is set, check if this is allowed.
+            if ($this->shareApiLinkEnforcePassword()) {
+                throw new \InvalidArgumentException('Passwords are enforced for link shares');
+            }
+
+            return;
+        }
+
+        // Let others verify the password
+        try {
+            $event = new GenericEvent($password);
+            $this->eventDispatcher->dispatch('OCP\PasswordPolicy::validate', $event);
+        } catch (HintException $e) {
+            throw new \Exception($e->getHint());
+        }
+    }
+
+    /**
+     * Check for generic requirements before creating a share
+     *
+     * @param \OCP\Share\IShare $share
+     * @throws \InvalidArgumentException
+     * @throws GenericShareException
+     *
+     * @suppress PhanUndeclaredClassMethod
+     */
+    protected function generalCreateChecks(\OCP\Share\IShare $share) {
+        if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER) {
+            // We expect a valid user as sharedWith for user shares
+            if (!$this->userManager->userExists($share->getSharedWith())) {
+                throw new \InvalidArgumentException('SharedWith is not a valid user');
+            }
+        } else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_GROUP) {
+            // We expect a valid group as sharedWith for group shares
+            if (!$this->groupManager->groupExists($share->getSharedWith())) {
+                throw new \InvalidArgumentException('SharedWith is not a valid group');
+            }
+        } else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK) {
+            if ($share->getSharedWith() !== null) {
+                throw new \InvalidArgumentException('SharedWith should be empty');
+            }
+        } else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_REMOTE) {
+            if ($share->getSharedWith() === null) {
+                throw new \InvalidArgumentException('SharedWith should not be empty');
+            }
+        } else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_EMAIL) {
+            if ($share->getSharedWith() === null) {
+                throw new \InvalidArgumentException('SharedWith should not be empty');
+            }
+        } else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_CIRCLE) {
+            $circle = \OCA\Circles\Api\v1\Circles::detailsCircle($share->getSharedWith());
+            if ($circle === null) {
+                throw new \InvalidArgumentException('SharedWith is not a valid circle');
+            }
+        } else {
+            // We can't handle other types yet
+            throw new \InvalidArgumentException('unknown share type');
+        }
+
+        // Verify the initiator of the share is set
+        if ($share->getSharedBy() === null) {
+            throw new \InvalidArgumentException('SharedBy should be set');
+        }
+
+        // Cannot share with yourself
+        if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER &&
+            $share->getSharedWith() === $share->getSharedBy()) {
+            throw new \InvalidArgumentException('Can’t share with yourself');
+        }
+
+        // The path should be set
+        if ($share->getNode() === null) {
+            throw new \InvalidArgumentException('Path should be set');
+        }
+
+        // And it should be a file or a folder
+        if (!($share->getNode() instanceof \OCP\Files\File) &&
+                !($share->getNode() instanceof \OCP\Files\Folder)) {
+            throw new \InvalidArgumentException('Path should be either a file or a folder');
+        }
+
+        // And you can't share your rootfolder
+        if ($this->userManager->userExists($share->getSharedBy())) {
+            $sharedPath = $this->rootFolder->getUserFolder($share->getSharedBy())->getPath();
+        } else {
+            $sharedPath = $this->rootFolder->getUserFolder($share->getShareOwner())->getPath();
+        }
+        if ($sharedPath === $share->getNode()->getPath()) {
+            throw new \InvalidArgumentException('You can’t share your root folder');
+        }
+
+        // Check if we actually have share permissions
+        if (!$share->getNode()->isShareable()) {
+            $message_t = $this->l->t('You are not allowed to share %s', [$share->getNode()->getPath()]);
+            throw new GenericShareException($message_t, $message_t, 404);
+        }
+
+        // Permissions should be set
+        if ($share->getPermissions() === null) {
+            throw new \InvalidArgumentException('A share requires permissions');
+        }
+
+        /*
 		 * Quick fix for #23536
 		 * Non moveable mount points do not have update and delete permissions
 		 * while we 'most likely' do have that on the storage.
 		 */
-		$permissions = $share->getNode()->getPermissions();
-		$mount = $share->getNode()->getMountPoint();
-		if (!($mount instanceof MoveableMount)) {
-			$permissions |= \OCP\Constants::PERMISSION_DELETE | \OCP\Constants::PERMISSION_UPDATE;
-		}
-
-		// Check that we do not share with more permissions than we have
-		if ($share->getPermissions() & ~$permissions) {
-			$message_t = $this->l->t('Can’t increase permissions of %s', [$share->getNode()->getPath()]);
-			throw new GenericShareException($message_t, $message_t, 404);
-		}
-
-
-		// Check that read permissions are always set
-		// Link shares are allowed to have no read permissions to allow upload to hidden folders
-		$noReadPermissionRequired = $share->getShareType() === \OCP\Share::SHARE_TYPE_LINK
-			|| $share->getShareType() === \OCP\Share::SHARE_TYPE_EMAIL;
-		if (!$noReadPermissionRequired &&
-			($share->getPermissions() & \OCP\Constants::PERMISSION_READ) === 0) {
-			throw new \InvalidArgumentException('Shares need at least read permissions');
-		}
-
-		if ($share->getNode() instanceof \OCP\Files\File) {
-			if ($share->getPermissions() & \OCP\Constants::PERMISSION_DELETE) {
-				$message_t = $this->l->t('Files can’t be shared with delete permissions');
-				throw new GenericShareException($message_t);
-			}
-			if ($share->getPermissions() & \OCP\Constants::PERMISSION_CREATE) {
-				$message_t = $this->l->t('Files can’t be shared with create permissions');
-				throw new GenericShareException($message_t);
-			}
-		}
-	}
-
-	/**
-	 * Validate if the expiration date fits the system settings
-	 *
-	 * @param \OCP\Share\IShare $share The share to validate the expiration date of
-	 * @return \OCP\Share\IShare The modified share object
-	 * @throws GenericShareException
-	 * @throws \InvalidArgumentException
-	 * @throws \Exception
-	 */
-	protected function validateExpirationDate(\OCP\Share\IShare $share) {
-
-		$expirationDate = $share->getExpirationDate();
-
-		if ($expirationDate !== null) {
-			//Make sure the expiration date is a date
-			$expirationDate->setTime(0, 0, 0);
-
-			$date = new \DateTime();
-			$date->setTime(0, 0, 0);
-			if ($date >= $expirationDate) {
-				$message = $this->l->t('Expiration date is in the past');
-				throw new GenericShareException($message, $message, 404);
-			}
-		}
-
-		// If expiredate is empty set a default one if there is a default
-		$fullId = null;
-		try {
-			$fullId = $share->getFullId();
-		} catch (\UnexpectedValueException $e) {
-			// This is a new share
-		}
-
-		if ($fullId === null && $expirationDate === null && $this->shareApiLinkDefaultExpireDate()) {
-			$expirationDate = new \DateTime();
-			$expirationDate->setTime(0,0,0);
-			$expirationDate->add(new \DateInterval('P'.$this->shareApiLinkDefaultExpireDays().'D'));
-		}
-
-		// If we enforce the expiration date check that is does not exceed
-		if ($this->shareApiLinkDefaultExpireDateEnforced()) {
-			if ($expirationDate === null) {
-				throw new \InvalidArgumentException('Expiration date is enforced');
-			}
-
-			$date = new \DateTime();
-			$date->setTime(0, 0, 0);
-			$date->add(new \DateInterval('P' . $this->shareApiLinkDefaultExpireDays() . 'D'));
-			if ($date < $expirationDate) {
-				$message = $this->l->t('Can’t set expiration date more than %s days in the future', [$this->shareApiLinkDefaultExpireDays()]);
-				throw new GenericShareException($message, $message, 404);
-			}
-		}
-
-		$accepted = true;
-		$message = '';
-		\OCP\Util::emitHook('\OC\Share', 'verifyExpirationDate', [
-			'expirationDate' => &$expirationDate,
-			'accepted' => &$accepted,
-			'message' => &$message,
-			'passwordSet' => $share->getPassword() !== null,
-		]);
-
-		if (!$accepted) {
-			throw new \Exception($message);
-		}
-
-		$share->setExpirationDate($expirationDate);
-
-		return $share;
-	}
-
-	/**
-	 * Check for pre share requirements for user shares
-	 *
-	 * @param \OCP\Share\IShare $share
-	 * @throws \Exception
-	 */
-	protected function userCreateChecks(\OCP\Share\IShare $share) {
-		// Check if we can share with group members only
-		if ($this->shareWithGroupMembersOnly()) {
-			$sharedBy = $this->userManager->get($share->getSharedBy());
-			$sharedWith = $this->userManager->get($share->getSharedWith());
-			// Verify we can share with this user
-			$groups = array_intersect(
-					$this->groupManager->getUserGroupIds($sharedBy),
-					$this->groupManager->getUserGroupIds($sharedWith)
-			);
-			if (empty($groups)) {
-				throw new \Exception('Sharing is only allowed with group members');
-			}
-		}
-
-		/*
+        $permissions = $share->getNode()->getPermissions();
+        $mount = $share->getNode()->getMountPoint();
+        if (!($mount instanceof MoveableMount)) {
+            $permissions |= \OCP\Constants::PERMISSION_DELETE | \OCP\Constants::PERMISSION_UPDATE;
+        }
+
+        // Check that we do not share with more permissions than we have
+        if ($share->getPermissions() & ~$permissions) {
+            $message_t = $this->l->t('Can’t increase permissions of %s', [$share->getNode()->getPath()]);
+            throw new GenericShareException($message_t, $message_t, 404);
+        }
+
+
+        // Check that read permissions are always set
+        // Link shares are allowed to have no read permissions to allow upload to hidden folders
+        $noReadPermissionRequired = $share->getShareType() === \OCP\Share::SHARE_TYPE_LINK
+            || $share->getShareType() === \OCP\Share::SHARE_TYPE_EMAIL;
+        if (!$noReadPermissionRequired &&
+            ($share->getPermissions() & \OCP\Constants::PERMISSION_READ) === 0) {
+            throw new \InvalidArgumentException('Shares need at least read permissions');
+        }
+
+        if ($share->getNode() instanceof \OCP\Files\File) {
+            if ($share->getPermissions() & \OCP\Constants::PERMISSION_DELETE) {
+                $message_t = $this->l->t('Files can’t be shared with delete permissions');
+                throw new GenericShareException($message_t);
+            }
+            if ($share->getPermissions() & \OCP\Constants::PERMISSION_CREATE) {
+                $message_t = $this->l->t('Files can’t be shared with create permissions');
+                throw new GenericShareException($message_t);
+            }
+        }
+    }
+
+    /**
+     * Validate if the expiration date fits the system settings
+     *
+     * @param \OCP\Share\IShare $share The share to validate the expiration date of
+     * @return \OCP\Share\IShare The modified share object
+     * @throws GenericShareException
+     * @throws \InvalidArgumentException
+     * @throws \Exception
+     */
+    protected function validateExpirationDate(\OCP\Share\IShare $share) {
+
+        $expirationDate = $share->getExpirationDate();
+
+        if ($expirationDate !== null) {
+            //Make sure the expiration date is a date
+            $expirationDate->setTime(0, 0, 0);
+
+            $date = new \DateTime();
+            $date->setTime(0, 0, 0);
+            if ($date >= $expirationDate) {
+                $message = $this->l->t('Expiration date is in the past');
+                throw new GenericShareException($message, $message, 404);
+            }
+        }
+
+        // If expiredate is empty set a default one if there is a default
+        $fullId = null;
+        try {
+            $fullId = $share->getFullId();
+        } catch (\UnexpectedValueException $e) {
+            // This is a new share
+        }
+
+        if ($fullId === null && $expirationDate === null && $this->shareApiLinkDefaultExpireDate()) {
+            $expirationDate = new \DateTime();
+            $expirationDate->setTime(0,0,0);
+            $expirationDate->add(new \DateInterval('P'.$this->shareApiLinkDefaultExpireDays().'D'));
+        }
+
+        // If we enforce the expiration date check that is does not exceed
+        if ($this->shareApiLinkDefaultExpireDateEnforced()) {
+            if ($expirationDate === null) {
+                throw new \InvalidArgumentException('Expiration date is enforced');
+            }
+
+            $date = new \DateTime();
+            $date->setTime(0, 0, 0);
+            $date->add(new \DateInterval('P' . $this->shareApiLinkDefaultExpireDays() . 'D'));
+            if ($date < $expirationDate) {
+                $message = $this->l->t('Can’t set expiration date more than %s days in the future', [$this->shareApiLinkDefaultExpireDays()]);
+                throw new GenericShareException($message, $message, 404);
+            }
+        }
+
+        $accepted = true;
+        $message = '';
+        \OCP\Util::emitHook('\OC\Share', 'verifyExpirationDate', [
+            'expirationDate' => &$expirationDate,
+            'accepted' => &$accepted,
+            'message' => &$message,
+            'passwordSet' => $share->getPassword() !== null,
+        ]);
+
+        if (!$accepted) {
+            throw new \Exception($message);
+        }
+
+        $share->setExpirationDate($expirationDate);
+
+        return $share;
+    }
+
+    /**
+     * Check for pre share requirements for user shares
+     *
+     * @param \OCP\Share\IShare $share
+     * @throws \Exception
+     */
+    protected function userCreateChecks(\OCP\Share\IShare $share) {
+        // Check if we can share with group members only
+        if ($this->shareWithGroupMembersOnly()) {
+            $sharedBy = $this->userManager->get($share->getSharedBy());
+            $sharedWith = $this->userManager->get($share->getSharedWith());
+            // Verify we can share with this user
+            $groups = array_intersect(
+                    $this->groupManager->getUserGroupIds($sharedBy),
+                    $this->groupManager->getUserGroupIds($sharedWith)
+            );
+            if (empty($groups)) {
+                throw new \Exception('Sharing is only allowed with group members');
+            }
+        }
+
+        /*
 		 * TODO: Could be costly, fix
 		 *
 		 * Also this is not what we want in the future.. then we want to squash identical shares.
 		 */
-		$provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_USER);
-		$existingShares = $provider->getSharesByPath($share->getNode());
-		foreach($existingShares as $existingShare) {
-			// Ignore if it is the same share
-			try {
-				if ($existingShare->getFullId() === $share->getFullId()) {
-					continue;
-				}
-			} catch (\UnexpectedValueException $e) {
-				//Shares are not identical
-			}
-
-			// Identical share already existst
-			if ($existingShare->getSharedWith() === $share->getSharedWith()) {
-				throw new \Exception('Path is already shared with this user');
-			}
-
-			// The share is already shared with this user via a group share
-			if ($existingShare->getShareType() === \OCP\Share::SHARE_TYPE_GROUP) {
-				$group = $this->groupManager->get($existingShare->getSharedWith());
-				if (!is_null($group)) {
-					$user = $this->userManager->get($share->getSharedWith());
-
-					if ($group->inGroup($user) && $existingShare->getShareOwner() !== $share->getShareOwner()) {
-						throw new \Exception('Path is already shared with this user');
-					}
-				}
-			}
-		}
-	}
-
-	/**
-	 * Check for pre share requirements for group shares
-	 *
-	 * @param \OCP\Share\IShare $share
-	 * @throws \Exception
-	 */
-	protected function groupCreateChecks(\OCP\Share\IShare $share) {
-		// Verify group shares are allowed
-		if (!$this->allowGroupSharing()) {
-			throw new \Exception('Group sharing is now allowed');
-		}
-
-		// Verify if the user can share with this group
-		if ($this->shareWithGroupMembersOnly()) {
-			$sharedBy = $this->userManager->get($share->getSharedBy());
-			$sharedWith = $this->groupManager->get($share->getSharedWith());
-			if (is_null($sharedWith) || !$sharedWith->inGroup($sharedBy)) {
-				throw new \Exception('Sharing is only allowed within your own groups');
-			}
-		}
-
-		/*
+        $provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_USER);
+        $existingShares = $provider->getSharesByPath($share->getNode());
+        foreach($existingShares as $existingShare) {
+            // Ignore if it is the same share
+            try {
+                if ($existingShare->getFullId() === $share->getFullId()) {
+                    continue;
+                }
+            } catch (\UnexpectedValueException $e) {
+                //Shares are not identical
+            }
+
+            // Identical share already existst
+            if ($existingShare->getSharedWith() === $share->getSharedWith()) {
+                throw new \Exception('Path is already shared with this user');
+            }
+
+            // The share is already shared with this user via a group share
+            if ($existingShare->getShareType() === \OCP\Share::SHARE_TYPE_GROUP) {
+                $group = $this->groupManager->get($existingShare->getSharedWith());
+                if (!is_null($group)) {
+                    $user = $this->userManager->get($share->getSharedWith());
+
+                    if ($group->inGroup($user) && $existingShare->getShareOwner() !== $share->getShareOwner()) {
+                        throw new \Exception('Path is already shared with this user');
+                    }
+                }
+            }
+        }
+    }
+
+    /**
+     * Check for pre share requirements for group shares
+     *
+     * @param \OCP\Share\IShare $share
+     * @throws \Exception
+     */
+    protected function groupCreateChecks(\OCP\Share\IShare $share) {
+        // Verify group shares are allowed
+        if (!$this->allowGroupSharing()) {
+            throw new \Exception('Group sharing is now allowed');
+        }
+
+        // Verify if the user can share with this group
+        if ($this->shareWithGroupMembersOnly()) {
+            $sharedBy = $this->userManager->get($share->getSharedBy());
+            $sharedWith = $this->groupManager->get($share->getSharedWith());
+            if (is_null($sharedWith) || !$sharedWith->inGroup($sharedBy)) {
+                throw new \Exception('Sharing is only allowed within your own groups');
+            }
+        }
+
+        /*
 		 * TODO: Could be costly, fix
 		 *
 		 * Also this is not what we want in the future.. then we want to squash identical shares.
 		 */
-		$provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_GROUP);
-		$existingShares = $provider->getSharesByPath($share->getNode());
-		foreach($existingShares as $existingShare) {
-			try {
-				if ($existingShare->getFullId() === $share->getFullId()) {
-					continue;
-				}
-			} catch (\UnexpectedValueException $e) {
-				//It is a new share so just continue
-			}
-
-			if ($existingShare->getSharedWith() === $share->getSharedWith()) {
-				throw new \Exception('Path is already shared with this group');
-			}
-		}
-	}
-
-	/**
-	 * Check for pre share requirements for link shares
-	 *
-	 * @param \OCP\Share\IShare $share
-	 * @throws \Exception
-	 */
-	protected function linkCreateChecks(\OCP\Share\IShare $share) {
-		// Are link shares allowed?
-		if (!$this->shareApiAllowLinks()) {
-			throw new \Exception('Link sharing is not allowed');
-		}
-
-		// Link shares by definition can't have share permissions
-		if ($share->getPermissions() & \OCP\Constants::PERMISSION_SHARE) {
-			throw new \InvalidArgumentException('Link shares can’t have reshare permissions');
-		}
-
-		// Check if public upload is allowed
-		if (!$this->shareApiLinkAllowPublicUpload() &&
-			($share->getPermissions() & (\OCP\Constants::PERMISSION_CREATE | \OCP\Constants::PERMISSION_UPDATE | \OCP\Constants::PERMISSION_DELETE))) {
-			throw new \InvalidArgumentException('Public upload is not allowed');
-		}
-	}
-
-	/**
-	 * To make sure we don't get invisible link shares we set the parent
-	 * of a link if it is a reshare. This is a quick word around
-	 * until we can properly display multiple link shares in the UI
-	 *
-	 * See: https://github.com/owncloud/core/issues/22295
-	 *
-	 * FIXME: Remove once multiple link shares can be properly displayed
-	 *
-	 * @param \OCP\Share\IShare $share
-	 */
-	protected function setLinkParent(\OCP\Share\IShare $share) {
-
-		// No sense in checking if the method is not there.
-		if (method_exists($share, 'setParent')) {
-			$storage = $share->getNode()->getStorage();
-			if ($storage->instanceOfStorage('\OCA\Files_Sharing\ISharedStorage')) {
-				/** @var \OCA\Files_Sharing\SharedStorage $storage */
-				$share->setParent($storage->getShareId());
-			}
-		};
-	}
-
-	/**
-	 * @param File|Folder $path
-	 */
-	protected function pathCreateChecks($path) {
-		// Make sure that we do not share a path that contains a shared mountpoint
-		if ($path instanceof \OCP\Files\Folder) {
-			$mounts = $this->mountManager->findIn($path->getPath());
-			foreach($mounts as $mount) {
-				if ($mount->getStorage()->instanceOfStorage('\OCA\Files_Sharing\ISharedStorage')) {
-					throw new \InvalidArgumentException('Path contains files shared with you');
-				}
-			}
-		}
-	}
-
-	/**
-	 * Check if the user that is sharing can actually share
-	 *
-	 * @param \OCP\Share\IShare $share
-	 * @throws \Exception
-	 */
-	protected function canShare(\OCP\Share\IShare $share) {
-		if (!$this->shareApiEnabled()) {
-			throw new \Exception('Sharing is disabled');
-		}
-
-		if ($this->sharingDisabledForUser($share->getSharedBy())) {
-			throw new \Exception('Sharing is disabled for you');
-		}
-	}
-
-	/**
-	 * Share a path
-	 *
-	 * @param \OCP\Share\IShare $share
-	 * @return Share The share object
-	 * @throws \Exception
-	 *
-	 * TODO: handle link share permissions or check them
-	 */
-	public function createShare(\OCP\Share\IShare $share) {
-		$this->canShare($share);
-
-		$this->generalCreateChecks($share);
-
-		// Verify if there are any issues with the path
-		$this->pathCreateChecks($share->getNode());
-
-		/*
+        $provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_GROUP);
+        $existingShares = $provider->getSharesByPath($share->getNode());
+        foreach($existingShares as $existingShare) {
+            try {
+                if ($existingShare->getFullId() === $share->getFullId()) {
+                    continue;
+                }
+            } catch (\UnexpectedValueException $e) {
+                //It is a new share so just continue
+            }
+
+            if ($existingShare->getSharedWith() === $share->getSharedWith()) {
+                throw new \Exception('Path is already shared with this group');
+            }
+        }
+    }
+
+    /**
+     * Check for pre share requirements for link shares
+     *
+     * @param \OCP\Share\IShare $share
+     * @throws \Exception
+     */
+    protected function linkCreateChecks(\OCP\Share\IShare $share) {
+        // Are link shares allowed?
+        if (!$this->shareApiAllowLinks()) {
+            throw new \Exception('Link sharing is not allowed');
+        }
+
+        // Link shares by definition can't have share permissions
+        if ($share->getPermissions() & \OCP\Constants::PERMISSION_SHARE) {
+            throw new \InvalidArgumentException('Link shares can’t have reshare permissions');
+        }
+
+        // Check if public upload is allowed
+        if (!$this->shareApiLinkAllowPublicUpload() &&
+            ($share->getPermissions() & (\OCP\Constants::PERMISSION_CREATE | \OCP\Constants::PERMISSION_UPDATE | \OCP\Constants::PERMISSION_DELETE))) {
+            throw new \InvalidArgumentException('Public upload is not allowed');
+        }
+    }
+
+    /**
+     * To make sure we don't get invisible link shares we set the parent
+     * of a link if it is a reshare. This is a quick word around
+     * until we can properly display multiple link shares in the UI
+     *
+     * See: https://github.com/owncloud/core/issues/22295
+     *
+     * FIXME: Remove once multiple link shares can be properly displayed
+     *
+     * @param \OCP\Share\IShare $share
+     */
+    protected function setLinkParent(\OCP\Share\IShare $share) {
+
+        // No sense in checking if the method is not there.
+        if (method_exists($share, 'setParent')) {
+            $storage = $share->getNode()->getStorage();
+            if ($storage->instanceOfStorage('\OCA\Files_Sharing\ISharedStorage')) {
+                /** @var \OCA\Files_Sharing\SharedStorage $storage */
+                $share->setParent($storage->getShareId());
+            }
+        };
+    }
+
+    /**
+     * @param File|Folder $path
+     */
+    protected function pathCreateChecks($path) {
+        // Make sure that we do not share a path that contains a shared mountpoint
+        if ($path instanceof \OCP\Files\Folder) {
+            $mounts = $this->mountManager->findIn($path->getPath());
+            foreach($mounts as $mount) {
+                if ($mount->getStorage()->instanceOfStorage('\OCA\Files_Sharing\ISharedStorage')) {
+                    throw new \InvalidArgumentException('Path contains files shared with you');
+                }
+            }
+        }
+    }
+
+    /**
+     * Check if the user that is sharing can actually share
+     *
+     * @param \OCP\Share\IShare $share
+     * @throws \Exception
+     */
+    protected function canShare(\OCP\Share\IShare $share) {
+        if (!$this->shareApiEnabled()) {
+            throw new \Exception('Sharing is disabled');
+        }
+
+        if ($this->sharingDisabledForUser($share->getSharedBy())) {
+            throw new \Exception('Sharing is disabled for you');
+        }
+    }
+
+    /**
+     * Share a path
+     *
+     * @param \OCP\Share\IShare $share
+     * @return Share The share object
+     * @throws \Exception
+     *
+     * TODO: handle link share permissions or check them
+     */
+    public function createShare(\OCP\Share\IShare $share) {
+        $this->canShare($share);
+
+        $this->generalCreateChecks($share);
+
+        // Verify if there are any issues with the path
+        $this->pathCreateChecks($share->getNode());
+
+        /*
 		 * On creation of a share the owner is always the owner of the path
 		 * Except for mounted federated shares.
 		 */
-		$storage = $share->getNode()->getStorage();
-		if ($storage->instanceOfStorage('OCA\Files_Sharing\External\Storage')) {
-			$parent = $share->getNode()->getParent();
-			while($parent->getStorage()->instanceOfStorage('OCA\Files_Sharing\External\Storage')) {
-				$parent = $parent->getParent();
-			}
-			$share->setShareOwner($parent->getOwner()->getUID());
-		} else {
-			$share->setShareOwner($share->getNode()->getOwner()->getUID());
-		}
-
-		//Verify share type
-		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER) {
-			$this->userCreateChecks($share);
-		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_GROUP) {
-			$this->groupCreateChecks($share);
-		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK) {
-			$this->linkCreateChecks($share);
-			$this->setLinkParent($share);
-
-			/*
+        $storage = $share->getNode()->getStorage();
+        if ($storage->instanceOfStorage('OCA\Files_Sharing\External\Storage')) {
+            $parent = $share->getNode()->getParent();
+            while($parent->getStorage()->instanceOfStorage('OCA\Files_Sharing\External\Storage')) {
+                $parent = $parent->getParent();
+            }
+            $share->setShareOwner($parent->getOwner()->getUID());
+        } else {
+            $share->setShareOwner($share->getNode()->getOwner()->getUID());
+        }
+
+        //Verify share type
+        if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER) {
+            $this->userCreateChecks($share);
+        } else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_GROUP) {
+            $this->groupCreateChecks($share);
+        } else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK) {
+            $this->linkCreateChecks($share);
+            $this->setLinkParent($share);
+
+            /*
 			 * For now ignore a set token.
 			 */
-			$share->setToken(
-				$this->secureRandom->generate(
-					\OC\Share\Constants::TOKEN_LENGTH,
-					\OCP\Security\ISecureRandom::CHAR_HUMAN_READABLE
-				)
-			);
-
-			//Verify the expiration date
-			$this->validateExpirationDate($share);
-
-			//Verify the password
-			$this->verifyPassword($share->getPassword());
-
-			// If a password is set. Hash it!
-			if ($share->getPassword() !== null) {
-				$share->setPassword($this->hasher->hash($share->getPassword()));
-			}
-		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_EMAIL) {
-			$share->setToken(
-				$this->secureRandom->generate(
-					\OC\Share\Constants::TOKEN_LENGTH,
-					\OCP\Security\ISecureRandom::CHAR_HUMAN_READABLE
-				)
-			);
-		}
-
-		// Cannot share with the owner
-		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER &&
-			$share->getSharedWith() === $share->getShareOwner()) {
-			throw new \InvalidArgumentException('Can’t share with the share owner');
-		}
-
-		// Generate the target
-		$target = $this->config->getSystemValue('share_folder', '/') .'/'. $share->getNode()->getName();
-		$target = \OC\Files\Filesystem::normalizePath($target);
-		$share->setTarget($target);
-
-		// Pre share hook
-		$run = true;
-		$error = '';
-		$preHookData = [
-			'itemType' => $share->getNode() instanceof \OCP\Files\File ? 'file' : 'folder',
-			'itemSource' => $share->getNode()->getId(),
-			'shareType' => $share->getShareType(),
-			'uidOwner' => $share->getSharedBy(),
-			'permissions' => $share->getPermissions(),
-			'fileSource' => $share->getNode()->getId(),
-			'expiration' => $share->getExpirationDate(),
-			'token' => $share->getToken(),
-			'itemTarget' => $share->getTarget(),
-			'shareWith' => $share->getSharedWith(),
-			'run' => &$run,
-			'error' => &$error,
-		];
-		\OC_Hook::emit('OCP\Share', 'pre_shared', $preHookData);
-
-		if ($run === false) {
-			throw new \Exception($error);
-		}
-
-		$oldShare = $share;
-		$provider = $this->factory->getProviderForType($share->getShareType());
-		$share = $provider->create($share);
-		//reuse the node we already have
-		$share->setNode($oldShare->getNode());
-
-		// Post share hook
-		$postHookData = [
-			'itemType' => $share->getNode() instanceof \OCP\Files\File ? 'file' : 'folder',
-			'itemSource' => $share->getNode()->getId(),
-			'shareType' => $share->getShareType(),
-			'uidOwner' => $share->getSharedBy(),
-			'permissions' => $share->getPermissions(),
-			'fileSource' => $share->getNode()->getId(),
-			'expiration' => $share->getExpirationDate(),
-			'token' => $share->getToken(),
-			'id' => $share->getId(),
-			'shareWith' => $share->getSharedWith(),
-			'itemTarget' => $share->getTarget(),
-			'fileTarget' => $share->getTarget(),
-		];
-
-		\OC_Hook::emit('OCP\Share', 'post_shared', $postHookData);
-
-		return $share;
-	}
-
-	/**
-	 * Update a share
-	 *
-	 * @param \OCP\Share\IShare $share
-	 * @return \OCP\Share\IShare The share object
-	 * @throws \InvalidArgumentException
-	 */
-	public function updateShare(\OCP\Share\IShare $share) {
-		$expirationDateUpdated = false;
-
-		$this->canShare($share);
-
-		try {
-			$originalShare = $this->getShareById($share->getFullId());
-		} catch (\UnexpectedValueException $e) {
-			throw new \InvalidArgumentException('Share does not have a full id');
-		}
-
-		// We can't change the share type!
-		if ($share->getShareType() !== $originalShare->getShareType()) {
-			throw new \InvalidArgumentException('Can’t change share type');
-		}
-
-		// We can only change the recipient on user shares
-		if ($share->getSharedWith() !== $originalShare->getSharedWith() &&
-		    $share->getShareType() !== \OCP\Share::SHARE_TYPE_USER) {
-			throw new \InvalidArgumentException('Can only update recipient on user shares');
-		}
-
-		// Cannot share with the owner
-		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER &&
-			$share->getSharedWith() === $share->getShareOwner()) {
-			throw new \InvalidArgumentException('Can’t share with the share owner');
-		}
-
-		$this->generalCreateChecks($share);
-
-		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER) {
-			$this->userCreateChecks($share);
-		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_GROUP) {
-			$this->groupCreateChecks($share);
-		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK) {
-			$this->linkCreateChecks($share);
-
-			$this->updateSharePasswordIfNeeded($share, $originalShare);
-
-			if ($share->getExpirationDate() != $originalShare->getExpirationDate()) {
-				//Verify the expiration date
-				$this->validateExpirationDate($share);
-				$expirationDateUpdated = true;
-			}
-		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_EMAIL) {
-			$plainTextPassword = $share->getPassword();
-			if (!$this->updateSharePasswordIfNeeded($share, $originalShare)) {
-				$plainTextPassword = null;
-			}
-		}
-
-		$this->pathCreateChecks($share->getNode());
-
-		// Now update the share!
-		$provider = $this->factory->getProviderForType($share->getShareType());
-		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_EMAIL) {
-			$share = $provider->update($share, $plainTextPassword);
-		} else {
-			$share = $provider->update($share);
-		}
-
-		if ($expirationDateUpdated === true) {
-			\OC_Hook::emit('OCP\Share', 'post_set_expiration_date', [
-				'itemType' => $share->getNode() instanceof \OCP\Files\File ? 'file' : 'folder',
-				'itemSource' => $share->getNode()->getId(),
-				'date' => $share->getExpirationDate(),
-				'uidOwner' => $share->getSharedBy(),
-			]);
-		}
-
-		if ($share->getPassword() !== $originalShare->getPassword()) {
-			\OC_Hook::emit('OCP\Share', 'post_update_password', [
-				'itemType' => $share->getNode() instanceof \OCP\Files\File ? 'file' : 'folder',
-				'itemSource' => $share->getNode()->getId(),
-				'uidOwner' => $share->getSharedBy(),
-				'token' => $share->getToken(),
-				'disabled' => is_null($share->getPassword()),
-			]);
-		}
-
-		if ($share->getPermissions() !== $originalShare->getPermissions()) {
-			if ($this->userManager->userExists($share->getShareOwner())) {
-				$userFolder = $this->rootFolder->getUserFolder($share->getShareOwner());
-			} else {
-				$userFolder = $this->rootFolder->getUserFolder($share->getSharedBy());
-			}
-			\OC_Hook::emit('OCP\Share', 'post_update_permissions', array(
-				'itemType' => $share->getNode() instanceof \OCP\Files\File ? 'file' : 'folder',
-				'itemSource' => $share->getNode()->getId(),
-				'shareType' => $share->getShareType(),
-				'shareWith' => $share->getSharedWith(),
-				'uidOwner' => $share->getSharedBy(),
-				'permissions' => $share->getPermissions(),
-				'path' => $userFolder->getRelativePath($share->getNode()->getPath()),
-			));
-		}
-
-		return $share;
-	}
-
-	/**
-	 * Updates the password of the given share if it is not the same as the
-	 * password of the original share.
-	 *
-	 * @param \OCP\Share\IShare $share the share to update its password.
-	 * @param \OCP\Share\IShare $originalShare the original share to compare its
-	 *        password with.
-	 * @return boolean whether the password was updated or not.
-	 */
-	private function updateSharePasswordIfNeeded(\OCP\Share\IShare $share, \OCP\Share\IShare $originalShare) {
-		// Password updated.
-		if ($share->getPassword() !== $originalShare->getPassword()) {
-			//Verify the password
-			$this->verifyPassword($share->getPassword());
-
-			// If a password is set. Hash it!
-			if ($share->getPassword() !== null) {
-				$share->setPassword($this->hasher->hash($share->getPassword()));
-
-				return true;
-			}
-		}
-
-		return false;
-	}
-
-	/**
-	 * Delete all the children of this share
-	 * FIXME: remove once https://github.com/owncloud/core/pull/21660 is in
-	 *
-	 * @param \OCP\Share\IShare $share
-	 * @return \OCP\Share\IShare[] List of deleted shares
-	 */
-	protected function deleteChildren(\OCP\Share\IShare $share) {
-		$deletedShares = [];
-
-		$provider = $this->factory->getProviderForType($share->getShareType());
-
-		foreach ($provider->getChildren($share) as $child) {
-			$deletedChildren = $this->deleteChildren($child);
-			$deletedShares = array_merge($deletedShares, $deletedChildren);
-
-			$provider->delete($child);
-			$deletedShares[] = $child;
-		}
-
-		return $deletedShares;
-	}
-
-	/**
-	 * Delete a share
-	 *
-	 * @param \OCP\Share\IShare $share
-	 * @throws ShareNotFound
-	 * @throws \InvalidArgumentException
-	 */
-	public function deleteShare(\OCP\Share\IShare $share) {
-
-		try {
-			$share->getFullId();
-		} catch (\UnexpectedValueException $e) {
-			throw new \InvalidArgumentException('Share does not have a full id');
-		}
-
-		$event = new GenericEvent($share);
-		$this->eventDispatcher->dispatch('OCP\Share::preUnshare', $event);
-
-		// Get all children and delete them as well
-		$deletedShares = $this->deleteChildren($share);
-
-		// Do the actual delete
-		$provider = $this->factory->getProviderForType($share->getShareType());
-		$provider->delete($share);
-
-		// All the deleted shares caused by this delete
-		$deletedShares[] = $share;
-
-		// Emit post hook
-		$event->setArgument('deletedShares', $deletedShares);
-		$this->eventDispatcher->dispatch('OCP\Share::postUnshare', $event);
-	}
-
-
-	/**
-	 * Unshare a file as the recipient.
-	 * This can be different from a regular delete for example when one of
-	 * the users in a groups deletes that share. But the provider should
-	 * handle this.
-	 *
-	 * @param \OCP\Share\IShare $share
-	 * @param string $recipientId
-	 */
-	public function deleteFromSelf(\OCP\Share\IShare $share, $recipientId) {
-		list($providerId, ) = $this->splitFullId($share->getFullId());
-		$provider = $this->factory->getProvider($providerId);
-
-		$provider->deleteFromSelf($share, $recipientId);
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function moveShare(\OCP\Share\IShare $share, $recipientId) {
-		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK) {
-			throw new \InvalidArgumentException('Can’t change target of link share');
-		}
-
-		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER && $share->getSharedWith() !== $recipientId) {
-			throw new \InvalidArgumentException('Invalid recipient');
-		}
-
-		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_GROUP) {
-			$sharedWith = $this->groupManager->get($share->getSharedWith());
-			if (is_null($sharedWith)) {
-				throw new \InvalidArgumentException('Group "' . $share->getSharedWith() . '" does not exist');
-			}
-			$recipient = $this->userManager->get($recipientId);
-			if (!$sharedWith->inGroup($recipient)) {
-				throw new \InvalidArgumentException('Invalid recipient');
-			}
-		}
-
-		list($providerId, ) = $this->splitFullId($share->getFullId());
-		$provider = $this->factory->getProvider($providerId);
-
-		$provider->move($share, $recipientId);
-	}
-
-	public function getSharesInFolder($userId, Folder $node, $reshares = false) {
-		$providers = $this->factory->getAllProviders();
-
-		return array_reduce($providers, function($shares, IShareProvider $provider) use ($userId, $node, $reshares) {
-			$newShares = $provider->getSharesInFolder($userId, $node, $reshares);
-			foreach ($newShares as $fid => $data) {
-				if (!isset($shares[$fid])) {
-					$shares[$fid] = [];
-				}
-
-				$shares[$fid] = array_merge($shares[$fid], $data);
-			}
-			return $shares;
-		}, []);
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function getSharesBy($userId, $shareType, $path = null, $reshares = false, $limit = 50, $offset = 0) {
-		if ($path !== null &&
-				!($path instanceof \OCP\Files\File) &&
-				!($path instanceof \OCP\Files\Folder)) {
-			throw new \InvalidArgumentException('invalid path');
-		}
-
-		try {
-			$provider = $this->factory->getProviderForType($shareType);
-		} catch (ProviderException $e) {
-			return [];
-		}
-
-		$shares = $provider->getSharesBy($userId, $shareType, $path, $reshares, $limit, $offset);
-
-		/*
+            $share->setToken(
+                $this->secureRandom->generate(
+                    \OC\Share\Constants::TOKEN_LENGTH,
+                    \OCP\Security\ISecureRandom::CHAR_HUMAN_READABLE
+                )
+            );
+
+            //Verify the expiration date
+            $this->validateExpirationDate($share);
+
+            //Verify the password
+            $this->verifyPassword($share->getPassword());
+
+            // If a password is set. Hash it!
+            if ($share->getPassword() !== null) {
+                $share->setPassword($this->hasher->hash($share->getPassword()));
+            }
+        } else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_EMAIL) {
+            $share->setToken(
+                $this->secureRandom->generate(
+                    \OC\Share\Constants::TOKEN_LENGTH,
+                    \OCP\Security\ISecureRandom::CHAR_HUMAN_READABLE
+                )
+            );
+        }
+
+        // Cannot share with the owner
+        if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER &&
+            $share->getSharedWith() === $share->getShareOwner()) {
+            throw new \InvalidArgumentException('Can’t share with the share owner');
+        }
+
+        // Generate the target
+        $target = $this->config->getSystemValue('share_folder', '/') .'/'. $share->getNode()->getName();
+        $target = \OC\Files\Filesystem::normalizePath($target);
+        $share->setTarget($target);
+
+        // Pre share hook
+        $run = true;
+        $error = '';
+        $preHookData = [
+            'itemType' => $share->getNode() instanceof \OCP\Files\File ? 'file' : 'folder',
+            'itemSource' => $share->getNode()->getId(),
+            'shareType' => $share->getShareType(),
+            'uidOwner' => $share->getSharedBy(),
+            'permissions' => $share->getPermissions(),
+            'fileSource' => $share->getNode()->getId(),
+            'expiration' => $share->getExpirationDate(),
+            'token' => $share->getToken(),
+            'itemTarget' => $share->getTarget(),
+            'shareWith' => $share->getSharedWith(),
+            'run' => &$run,
+            'error' => &$error,
+        ];
+        \OC_Hook::emit('OCP\Share', 'pre_shared', $preHookData);
+
+        if ($run === false) {
+            throw new \Exception($error);
+        }
+
+        $oldShare = $share;
+        $provider = $this->factory->getProviderForType($share->getShareType());
+        $share = $provider->create($share);
+        //reuse the node we already have
+        $share->setNode($oldShare->getNode());
+
+        // Post share hook
+        $postHookData = [
+            'itemType' => $share->getNode() instanceof \OCP\Files\File ? 'file' : 'folder',
+            'itemSource' => $share->getNode()->getId(),
+            'shareType' => $share->getShareType(),
+            'uidOwner' => $share->getSharedBy(),
+            'permissions' => $share->getPermissions(),
+            'fileSource' => $share->getNode()->getId(),
+            'expiration' => $share->getExpirationDate(),
+            'token' => $share->getToken(),
+            'id' => $share->getId(),
+            'shareWith' => $share->getSharedWith(),
+            'itemTarget' => $share->getTarget(),
+            'fileTarget' => $share->getTarget(),
+        ];
+
+        \OC_Hook::emit('OCP\Share', 'post_shared', $postHookData);
+
+        return $share;
+    }
+
+    /**
+     * Update a share
+     *
+     * @param \OCP\Share\IShare $share
+     * @return \OCP\Share\IShare The share object
+     * @throws \InvalidArgumentException
+     */
+    public function updateShare(\OCP\Share\IShare $share) {
+        $expirationDateUpdated = false;
+
+        $this->canShare($share);
+
+        try {
+            $originalShare = $this->getShareById($share->getFullId());
+        } catch (\UnexpectedValueException $e) {
+            throw new \InvalidArgumentException('Share does not have a full id');
+        }
+
+        // We can't change the share type!
+        if ($share->getShareType() !== $originalShare->getShareType()) {
+            throw new \InvalidArgumentException('Can’t change share type');
+        }
+
+        // We can only change the recipient on user shares
+        if ($share->getSharedWith() !== $originalShare->getSharedWith() &&
+            $share->getShareType() !== \OCP\Share::SHARE_TYPE_USER) {
+            throw new \InvalidArgumentException('Can only update recipient on user shares');
+        }
+
+        // Cannot share with the owner
+        if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER &&
+            $share->getSharedWith() === $share->getShareOwner()) {
+            throw new \InvalidArgumentException('Can’t share with the share owner');
+        }
+
+        $this->generalCreateChecks($share);
+
+        if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER) {
+            $this->userCreateChecks($share);
+        } else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_GROUP) {
+            $this->groupCreateChecks($share);
+        } else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK) {
+            $this->linkCreateChecks($share);
+
+            $this->updateSharePasswordIfNeeded($share, $originalShare);
+
+            if ($share->getExpirationDate() != $originalShare->getExpirationDate()) {
+                //Verify the expiration date
+                $this->validateExpirationDate($share);
+                $expirationDateUpdated = true;
+            }
+        } else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_EMAIL) {
+            $plainTextPassword = $share->getPassword();
+            if (!$this->updateSharePasswordIfNeeded($share, $originalShare)) {
+                $plainTextPassword = null;
+            }
+        }
+
+        $this->pathCreateChecks($share->getNode());
+
+        // Now update the share!
+        $provider = $this->factory->getProviderForType($share->getShareType());
+        if ($share->getShareType() === \OCP\Share::SHARE_TYPE_EMAIL) {
+            $share = $provider->update($share, $plainTextPassword);
+        } else {
+            $share = $provider->update($share);
+        }
+
+        if ($expirationDateUpdated === true) {
+            \OC_Hook::emit('OCP\Share', 'post_set_expiration_date', [
+                'itemType' => $share->getNode() instanceof \OCP\Files\File ? 'file' : 'folder',
+                'itemSource' => $share->getNode()->getId(),
+                'date' => $share->getExpirationDate(),
+                'uidOwner' => $share->getSharedBy(),
+            ]);
+        }
+
+        if ($share->getPassword() !== $originalShare->getPassword()) {
+            \OC_Hook::emit('OCP\Share', 'post_update_password', [
+                'itemType' => $share->getNode() instanceof \OCP\Files\File ? 'file' : 'folder',
+                'itemSource' => $share->getNode()->getId(),
+                'uidOwner' => $share->getSharedBy(),
+                'token' => $share->getToken(),
+                'disabled' => is_null($share->getPassword()),
+            ]);
+        }
+
+        if ($share->getPermissions() !== $originalShare->getPermissions()) {
+            if ($this->userManager->userExists($share->getShareOwner())) {
+                $userFolder = $this->rootFolder->getUserFolder($share->getShareOwner());
+            } else {
+                $userFolder = $this->rootFolder->getUserFolder($share->getSharedBy());
+            }
+            \OC_Hook::emit('OCP\Share', 'post_update_permissions', array(
+                'itemType' => $share->getNode() instanceof \OCP\Files\File ? 'file' : 'folder',
+                'itemSource' => $share->getNode()->getId(),
+                'shareType' => $share->getShareType(),
+                'shareWith' => $share->getSharedWith(),
+                'uidOwner' => $share->getSharedBy(),
+                'permissions' => $share->getPermissions(),
+                'path' => $userFolder->getRelativePath($share->getNode()->getPath()),
+            ));
+        }
+
+        return $share;
+    }
+
+    /**
+     * Updates the password of the given share if it is not the same as the
+     * password of the original share.
+     *
+     * @param \OCP\Share\IShare $share the share to update its password.
+     * @param \OCP\Share\IShare $originalShare the original share to compare its
+     *        password with.
+     * @return boolean whether the password was updated or not.
+     */
+    private function updateSharePasswordIfNeeded(\OCP\Share\IShare $share, \OCP\Share\IShare $originalShare) {
+        // Password updated.
+        if ($share->getPassword() !== $originalShare->getPassword()) {
+            //Verify the password
+            $this->verifyPassword($share->getPassword());
+
+            // If a password is set. Hash it!
+            if ($share->getPassword() !== null) {
+                $share->setPassword($this->hasher->hash($share->getPassword()));
+
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Delete all the children of this share
+     * FIXME: remove once https://github.com/owncloud/core/pull/21660 is in
+     *
+     * @param \OCP\Share\IShare $share
+     * @return \OCP\Share\IShare[] List of deleted shares
+     */
+    protected function deleteChildren(\OCP\Share\IShare $share) {
+        $deletedShares = [];
+
+        $provider = $this->factory->getProviderForType($share->getShareType());
+
+        foreach ($provider->getChildren($share) as $child) {
+            $deletedChildren = $this->deleteChildren($child);
+            $deletedShares = array_merge($deletedShares, $deletedChildren);
+
+            $provider->delete($child);
+            $deletedShares[] = $child;
+        }
+
+        return $deletedShares;
+    }
+
+    /**
+     * Delete a share
+     *
+     * @param \OCP\Share\IShare $share
+     * @throws ShareNotFound
+     * @throws \InvalidArgumentException
+     */
+    public function deleteShare(\OCP\Share\IShare $share) {
+
+        try {
+            $share->getFullId();
+        } catch (\UnexpectedValueException $e) {
+            throw new \InvalidArgumentException('Share does not have a full id');
+        }
+
+        $event = new GenericEvent($share);
+        $this->eventDispatcher->dispatch('OCP\Share::preUnshare', $event);
+
+        // Get all children and delete them as well
+        $deletedShares = $this->deleteChildren($share);
+
+        // Do the actual delete
+        $provider = $this->factory->getProviderForType($share->getShareType());
+        $provider->delete($share);
+
+        // All the deleted shares caused by this delete
+        $deletedShares[] = $share;
+
+        // Emit post hook
+        $event->setArgument('deletedShares', $deletedShares);
+        $this->eventDispatcher->dispatch('OCP\Share::postUnshare', $event);
+    }
+
+
+    /**
+     * Unshare a file as the recipient.
+     * This can be different from a regular delete for example when one of
+     * the users in a groups deletes that share. But the provider should
+     * handle this.
+     *
+     * @param \OCP\Share\IShare $share
+     * @param string $recipientId
+     */
+    public function deleteFromSelf(\OCP\Share\IShare $share, $recipientId) {
+        list($providerId, ) = $this->splitFullId($share->getFullId());
+        $provider = $this->factory->getProvider($providerId);
+
+        $provider->deleteFromSelf($share, $recipientId);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function moveShare(\OCP\Share\IShare $share, $recipientId) {
+        if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK) {
+            throw new \InvalidArgumentException('Can’t change target of link share');
+        }
+
+        if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER && $share->getSharedWith() !== $recipientId) {
+            throw new \InvalidArgumentException('Invalid recipient');
+        }
+
+        if ($share->getShareType() === \OCP\Share::SHARE_TYPE_GROUP) {
+            $sharedWith = $this->groupManager->get($share->getSharedWith());
+            if (is_null($sharedWith)) {
+                throw new \InvalidArgumentException('Group "' . $share->getSharedWith() . '" does not exist');
+            }
+            $recipient = $this->userManager->get($recipientId);
+            if (!$sharedWith->inGroup($recipient)) {
+                throw new \InvalidArgumentException('Invalid recipient');
+            }
+        }
+
+        list($providerId, ) = $this->splitFullId($share->getFullId());
+        $provider = $this->factory->getProvider($providerId);
+
+        $provider->move($share, $recipientId);
+    }
+
+    public function getSharesInFolder($userId, Folder $node, $reshares = false) {
+        $providers = $this->factory->getAllProviders();
+
+        return array_reduce($providers, function($shares, IShareProvider $provider) use ($userId, $node, $reshares) {
+            $newShares = $provider->getSharesInFolder($userId, $node, $reshares);
+            foreach ($newShares as $fid => $data) {
+                if (!isset($shares[$fid])) {
+                    $shares[$fid] = [];
+                }
+
+                $shares[$fid] = array_merge($shares[$fid], $data);
+            }
+            return $shares;
+        }, []);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getSharesBy($userId, $shareType, $path = null, $reshares = false, $limit = 50, $offset = 0) {
+        if ($path !== null &&
+                !($path instanceof \OCP\Files\File) &&
+                !($path instanceof \OCP\Files\Folder)) {
+            throw new \InvalidArgumentException('invalid path');
+        }
+
+        try {
+            $provider = $this->factory->getProviderForType($shareType);
+        } catch (ProviderException $e) {
+            return [];
+        }
+
+        $shares = $provider->getSharesBy($userId, $shareType, $path, $reshares, $limit, $offset);
+
+        /*
 		 * Work around so we don't return expired shares but still follow
 		 * proper pagination.
 		 */
 
-		$shares2 = [];
-
-		while(true) {
-			$added = 0;
-			foreach ($shares as $share) {
-
-				try {
-					$this->checkExpireDate($share);
-				} catch (ShareNotFound $e) {
-					//Ignore since this basically means the share is deleted
-					continue;
-				}
-
-				$added++;
-				$shares2[] = $share;
-
-				if (count($shares2) === $limit) {
-					break;
-				}
-			}
-
-			if (count($shares2) === $limit) {
-				break;
-			}
-
-			// If there was no limit on the select we are done
-			if ($limit === -1) {
-				break;
-			}
-
-			$offset += $added;
-
-			// Fetch again $limit shares
-			$shares = $provider->getSharesBy($userId, $shareType, $path, $reshares, $limit, $offset);
-
-			// No more shares means we are done
-			if (empty($shares)) {
-				break;
-			}
-		}
-
-		$shares = $shares2;
-
-		return $shares;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function getSharedWith($userId, $shareType, $node = null, $limit = 50, $offset = 0) {
-		try {
-			$provider = $this->factory->getProviderForType($shareType);
-		} catch (ProviderException $e) {
-			return [];
-		}
-
-		$shares = $provider->getSharedWith($userId, $shareType, $node, $limit, $offset);
-
-		// remove all shares which are already expired
-		foreach ($shares as $key => $share) {
-			try {
-				$this->checkExpireDate($share);
-			} catch (ShareNotFound $e) {
-				unset($shares[$key]);
-			}
-		}
-
-		return $shares;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function getShareById($id, $recipient = null) {
-		if ($id === null) {
-			throw new ShareNotFound();
-		}
-
-		list($providerId, $id) = $this->splitFullId($id);
-
-		try {
-			$provider = $this->factory->getProvider($providerId);
-		} catch (ProviderException $e) {
-			throw new ShareNotFound();
-		}
-
-		$share = $provider->getShareById($id, $recipient);
-
-		$this->checkExpireDate($share);
-
-		return $share;
-	}
-
-	/**
-	 * Get all the shares for a given path
-	 *
-	 * @param \OCP\Files\Node $path
-	 * @param int $page
-	 * @param int $perPage
-	 *
-	 * @return Share[]
-	 */
-	public function getSharesByPath(\OCP\Files\Node $path, $page=0, $perPage=50) {
-		return [];
-	}
-
-	/**
-	 * Get the share by token possible with password
-	 *
-	 * @param string $token
-	 * @return Share
-	 *
-	 * @throws ShareNotFound
-	 */
-	public function getShareByToken($token) {
-		$share = null;
-		try {
-			if($this->shareApiAllowLinks()) {
-				$provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_LINK);
-				$share = $provider->getShareByToken($token);
-			}
-		} catch (ProviderException $e) {
-		} catch (ShareNotFound $e) {
-		}
-
-
-		// If it is not a link share try to fetch a federated share by token
-		if ($share === null) {
-			try {
-				$provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_REMOTE);
-				$share = $provider->getShareByToken($token);
-			} catch (ProviderException $e) {
-			} catch (ShareNotFound $e) {
-			}
-		}
-
-		// If it is not a link share try to fetch a mail share by token
-		if ($share === null && $this->shareProviderExists(\OCP\Share::SHARE_TYPE_EMAIL)) {
-			try {
-				$provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_EMAIL);
-				$share = $provider->getShareByToken($token);
-			} catch (ProviderException $e) {
-			} catch (ShareNotFound $e) {
-			}
-		}
-
-		if ($share === null) {
-			throw new ShareNotFound($this->l->t('The requested share does not exist anymore'));
-		}
-
-		$this->checkExpireDate($share);
-
-		/*
+        $shares2 = [];
+
+        while(true) {
+            $added = 0;
+            foreach ($shares as $share) {
+
+                try {
+                    $this->checkExpireDate($share);
+                } catch (ShareNotFound $e) {
+                    //Ignore since this basically means the share is deleted
+                    continue;
+                }
+
+                $added++;
+                $shares2[] = $share;
+
+                if (count($shares2) === $limit) {
+                    break;
+                }
+            }
+
+            if (count($shares2) === $limit) {
+                break;
+            }
+
+            // If there was no limit on the select we are done
+            if ($limit === -1) {
+                break;
+            }
+
+            $offset += $added;
+
+            // Fetch again $limit shares
+            $shares = $provider->getSharesBy($userId, $shareType, $path, $reshares, $limit, $offset);
+
+            // No more shares means we are done
+            if (empty($shares)) {
+                break;
+            }
+        }
+
+        $shares = $shares2;
+
+        return $shares;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getSharedWith($userId, $shareType, $node = null, $limit = 50, $offset = 0) {
+        try {
+            $provider = $this->factory->getProviderForType($shareType);
+        } catch (ProviderException $e) {
+            return [];
+        }
+
+        $shares = $provider->getSharedWith($userId, $shareType, $node, $limit, $offset);
+
+        // remove all shares which are already expired
+        foreach ($shares as $key => $share) {
+            try {
+                $this->checkExpireDate($share);
+            } catch (ShareNotFound $e) {
+                unset($shares[$key]);
+            }
+        }
+
+        return $shares;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getShareById($id, $recipient = null) {
+        if ($id === null) {
+            throw new ShareNotFound();
+        }
+
+        list($providerId, $id) = $this->splitFullId($id);
+
+        try {
+            $provider = $this->factory->getProvider($providerId);
+        } catch (ProviderException $e) {
+            throw new ShareNotFound();
+        }
+
+        $share = $provider->getShareById($id, $recipient);
+
+        $this->checkExpireDate($share);
+
+        return $share;
+    }
+
+    /**
+     * Get all the shares for a given path
+     *
+     * @param \OCP\Files\Node $path
+     * @param int $page
+     * @param int $perPage
+     *
+     * @return Share[]
+     */
+    public function getSharesByPath(\OCP\Files\Node $path, $page=0, $perPage=50) {
+        return [];
+    }
+
+    /**
+     * Get the share by token possible with password
+     *
+     * @param string $token
+     * @return Share
+     *
+     * @throws ShareNotFound
+     */
+    public function getShareByToken($token) {
+        $share = null;
+        try {
+            if($this->shareApiAllowLinks()) {
+                $provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_LINK);
+                $share = $provider->getShareByToken($token);
+            }
+        } catch (ProviderException $e) {
+        } catch (ShareNotFound $e) {
+        }
+
+
+        // If it is not a link share try to fetch a federated share by token
+        if ($share === null) {
+            try {
+                $provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_REMOTE);
+                $share = $provider->getShareByToken($token);
+            } catch (ProviderException $e) {
+            } catch (ShareNotFound $e) {
+            }
+        }
+
+        // If it is not a link share try to fetch a mail share by token
+        if ($share === null && $this->shareProviderExists(\OCP\Share::SHARE_TYPE_EMAIL)) {
+            try {
+                $provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_EMAIL);
+                $share = $provider->getShareByToken($token);
+            } catch (ProviderException $e) {
+            } catch (ShareNotFound $e) {
+            }
+        }
+
+        if ($share === null) {
+            throw new ShareNotFound($this->l->t('The requested share does not exist anymore'));
+        }
+
+        $this->checkExpireDate($share);
+
+        /*
 		 * Reduce the permissions for link shares if public upload is not enabled
 		 */
-		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK &&
-			!$this->shareApiLinkAllowPublicUpload()) {
-			$share->setPermissions($share->getPermissions() & ~(\OCP\Constants::PERMISSION_CREATE | \OCP\Constants::PERMISSION_UPDATE));
-		}
-
-		return $share;
-	}
-
-	protected function checkExpireDate($share) {
-		if ($share->getExpirationDate() !== null &&
-			$share->getExpirationDate() <= new \DateTime()) {
-			$this->deleteShare($share);
-			throw new ShareNotFound($this->l->t('The requested share does not exist anymore'));
-		}
-
-	}
-
-	/**
-	 * Verify the password of a public share
-	 *
-	 * @param \OCP\Share\IShare $share
-	 * @param string $password
-	 * @return bool
-	 */
-	public function checkPassword(\OCP\Share\IShare $share, $password) {
-		$passwordProtected = $share->getShareType() !== \OCP\Share::SHARE_TYPE_LINK
-			|| $share->getShareType() !== \OCP\Share::SHARE_TYPE_EMAIL;
-		if (!$passwordProtected) {
-			//TODO maybe exception?
-			return false;
-		}
-
-		if ($password === null || $share->getPassword() === null) {
-			return false;
-		}
-
-		$newHash = '';
-		if (!$this->hasher->verify($password, $share->getPassword(), $newHash)) {
-			return false;
-		}
-
-		if (!empty($newHash)) {
-			$share->setPassword($newHash);
-			$provider = $this->factory->getProviderForType($share->getShareType());
-			$provider->update($share);
-		}
-
-		return true;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function userDeleted($uid) {
-		$types = [\OCP\Share::SHARE_TYPE_USER, \OCP\Share::SHARE_TYPE_GROUP, \OCP\Share::SHARE_TYPE_LINK, \OCP\Share::SHARE_TYPE_REMOTE, \OCP\Share::SHARE_TYPE_EMAIL];
-
-		foreach ($types as $type) {
-			try {
-				$provider = $this->factory->getProviderForType($type);
-			} catch (ProviderException $e) {
-				continue;
-			}
-			$provider->userDeleted($uid, $type);
-		}
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function groupDeleted($gid) {
-		$provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_GROUP);
-		$provider->groupDeleted($gid);
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function userDeletedFromGroup($uid, $gid) {
-		$provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_GROUP);
-		$provider->userDeletedFromGroup($uid, $gid);
-	}
-
-	/**
-	 * Get access list to a path. This means
-	 * all the users that can access a given path.
-	 *
-	 * Consider:
-	 * -root
-	 * |-folder1 (23)
-	 *  |-folder2 (32)
-	 *   |-fileA (42)
-	 *
-	 * fileA is shared with user1 and user1@server1
-	 * folder2 is shared with group2 (user4 is a member of group2)
-	 * folder1 is shared with user2 (renamed to "folder (1)") and user2@server2
-	 *
-	 * Then the access list to '/folder1/folder2/fileA' with $currentAccess is:
-	 * [
-	 *  users  => [
-	 *      'user1' => ['node_id' => 42, 'node_path' => '/fileA'],
-	 *      'user4' => ['node_id' => 32, 'node_path' => '/folder2'],
-	 *      'user2' => ['node_id' => 23, 'node_path' => '/folder (1)'],
-	 *  ],
-	 *  remote => [
-	 *      'user1@server1' => ['node_id' => 42, 'token' => 'SeCr3t'],
-	 *      'user2@server2' => ['node_id' => 23, 'token' => 'FooBaR'],
-	 *  ],
-	 *  public => bool
-	 *  mail => bool
-	 * ]
-	 *
-	 * The access list to '/folder1/folder2/fileA' **without** $currentAccess is:
-	 * [
-	 *  users  => ['user1', 'user2', 'user4'],
-	 *  remote => bool,
-	 *  public => bool
-	 *  mail => bool
-	 * ]
-	 *
-	 * This is required for encryption/activity
-	 *
-	 * @param \OCP\Files\Node $path
-	 * @param bool $recursive Should we check all parent folders as well
-	 * @param bool $currentAccess Should the user have currently access to the file
-	 * @return array
-	 */
-	public function getAccessList(\OCP\Files\Node $path, $recursive = true, $currentAccess = false) {
-		$owner = $path->getOwner()->getUID();
-
-		if ($currentAccess) {
-			$al = ['users' => [], 'remote' => [], 'public' => false];
-		} else {
-			$al = ['users' => [], 'remote' => false, 'public' => false];
-		}
-		if (!$this->userManager->userExists($owner)) {
-			return $al;
-		}
-
-		//Get node for the owner
-		$userFolder = $this->rootFolder->getUserFolder($owner);
-		if ($path->getId() !== $userFolder->getId() && !$userFolder->isSubNode($path)) {
-			$path = $userFolder->getById($path->getId())[0];
-		}
-
-		$providers = $this->factory->getAllProviders();
-
-		/** @var Node[] $nodes */
-		$nodes = [];
-
-
-		if ($currentAccess) {
-			$ownerPath = $path->getPath();
-			$ownerPath = explode('/', $ownerPath, 4);
-			if (count($ownerPath) < 4) {
-				$ownerPath = '';
-			} else {
-				$ownerPath = $ownerPath[3];
-			}
-			$al['users'][$owner] = [
-				'node_id' => $path->getId(),
-				'node_path' => '/' . $ownerPath,
-			];
-		} else {
-			$al['users'][] = $owner;
-		}
-
-		// Collect all the shares
-		while ($path->getPath() !== $userFolder->getPath()) {
-			$nodes[] = $path;
-			if (!$recursive) {
-				break;
-			}
-			$path = $path->getParent();
-		}
-
-		foreach ($providers as $provider) {
-			$tmp = $provider->getAccessList($nodes, $currentAccess);
-
-			foreach ($tmp as $k => $v) {
-				if (isset($al[$k])) {
-					if (is_array($al[$k])) {
-						$al[$k] = array_merge($al[$k], $v);
-					} else {
-						$al[$k] = $al[$k] || $v;
-					}
-				} else {
-					$al[$k] = $v;
-				}
-			}
-		}
-
-		return $al;
-	}
-
-	/**
-	 * Create a new share
-	 * @return \OCP\Share\IShare;
-	 */
-	public function newShare() {
-		return new \OC\Share20\Share($this->rootFolder, $this->userManager);
-	}
-
-	/**
-	 * Is the share API enabled
-	 *
-	 * @return bool
-	 */
-	public function shareApiEnabled() {
-		return $this->config->getAppValue('core', 'shareapi_enabled', 'yes') === 'yes';
-	}
-
-	/**
-	 * Is public link sharing enabled
-	 *
-	 * @return bool
-	 */
-	public function shareApiAllowLinks() {
-		return $this->config->getAppValue('core', 'shareapi_allow_links', 'yes') === 'yes';
-	}
-
-	/**
-	 * Is password on public link requires
-	 *
-	 * @return bool
-	 */
-	public function shareApiLinkEnforcePassword() {
-		return $this->config->getAppValue('core', 'shareapi_enforce_links_password', 'no') === 'yes';
-	}
-
-	/**
-	 * Is default expire date enabled
-	 *
-	 * @return bool
-	 */
-	public function shareApiLinkDefaultExpireDate() {
-		return $this->config->getAppValue('core', 'shareapi_default_expire_date', 'no') === 'yes';
-	}
-
-	/**
-	 * Is default expire date enforced
-	 *`
-	 * @return bool
-	 */
-	public function shareApiLinkDefaultExpireDateEnforced() {
-		return $this->shareApiLinkDefaultExpireDate() &&
-			$this->config->getAppValue('core', 'shareapi_enforce_expire_date', 'no') === 'yes';
-	}
-
-	/**
-	 * Number of default expire days
-	 *shareApiLinkAllowPublicUpload
-	 * @return int
-	 */
-	public function shareApiLinkDefaultExpireDays() {
-		return (int)$this->config->getAppValue('core', 'shareapi_expire_after_n_days', '7');
-	}
-
-	/**
-	 * Allow public upload on link shares
-	 *
-	 * @return bool
-	 */
-	public function shareApiLinkAllowPublicUpload() {
-		return $this->config->getAppValue('core', 'shareapi_allow_public_upload', 'yes') === 'yes';
-	}
-
-	/**
-	 * check if user can only share with group members
-	 * @return bool
-	 */
-	public function shareWithGroupMembersOnly() {
-		return $this->config->getAppValue('core', 'shareapi_only_share_with_group_members', 'no') === 'yes';
-	}
-
-	/**
-	 * Check if users can share with groups
-	 * @return bool
-	 */
-	public function allowGroupSharing() {
-		return $this->config->getAppValue('core', 'shareapi_allow_group_sharing', 'yes') === 'yes';
-	}
-
-	/**
-	 * Copied from \OC_Util::isSharingDisabledForUser
-	 *
-	 * TODO: Deprecate fuction from OC_Util
-	 *
-	 * @param string $userId
-	 * @return bool
-	 */
-	public function sharingDisabledForUser($userId) {
-		if ($userId === null) {
-			return false;
-		}
-
-		if (isset($this->sharingDisabledForUsersCache[$userId])) {
-			return $this->sharingDisabledForUsersCache[$userId];
-		}
-
-		if ($this->config->getAppValue('core', 'shareapi_exclude_groups', 'no') === 'yes') {
-			$groupsList = $this->config->getAppValue('core', 'shareapi_exclude_groups_list', '');
-			$excludedGroups = json_decode($groupsList);
-			if (is_null($excludedGroups)) {
-				$excludedGroups = explode(',', $groupsList);
-				$newValue = json_encode($excludedGroups);
-				$this->config->setAppValue('core', 'shareapi_exclude_groups_list', $newValue);
-			}
-			$user = $this->userManager->get($userId);
-			$usersGroups = $this->groupManager->getUserGroupIds($user);
-			if (!empty($usersGroups)) {
-				$remainingGroups = array_diff($usersGroups, $excludedGroups);
-				// if the user is only in groups which are disabled for sharing then
-				// sharing is also disabled for the user
-				if (empty($remainingGroups)) {
-					$this->sharingDisabledForUsersCache[$userId] = true;
-					return true;
-				}
-			}
-		}
-
-		$this->sharingDisabledForUsersCache[$userId] = false;
-		return false;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function outgoingServer2ServerSharesAllowed() {
-		return $this->config->getAppValue('files_sharing', 'outgoing_server2server_share_enabled', 'yes') === 'yes';
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function shareProviderExists($shareType) {
-		try {
-			$this->factory->getProviderForType($shareType);
-		} catch (ProviderException $e) {
-			return false;
-		}
-
-		return true;
-	}
+        if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK &&
+            !$this->shareApiLinkAllowPublicUpload()) {
+            $share->setPermissions($share->getPermissions() & ~(\OCP\Constants::PERMISSION_CREATE | \OCP\Constants::PERMISSION_UPDATE));
+        }
+
+        return $share;
+    }
+
+    protected function checkExpireDate($share) {
+        if ($share->getExpirationDate() !== null &&
+            $share->getExpirationDate() <= new \DateTime()) {
+            $this->deleteShare($share);
+            throw new ShareNotFound($this->l->t('The requested share does not exist anymore'));
+        }
+
+    }
+
+    /**
+     * Verify the password of a public share
+     *
+     * @param \OCP\Share\IShare $share
+     * @param string $password
+     * @return bool
+     */
+    public function checkPassword(\OCP\Share\IShare $share, $password) {
+        $passwordProtected = $share->getShareType() !== \OCP\Share::SHARE_TYPE_LINK
+            || $share->getShareType() !== \OCP\Share::SHARE_TYPE_EMAIL;
+        if (!$passwordProtected) {
+            //TODO maybe exception?
+            return false;
+        }
+
+        if ($password === null || $share->getPassword() === null) {
+            return false;
+        }
+
+        $newHash = '';
+        if (!$this->hasher->verify($password, $share->getPassword(), $newHash)) {
+            return false;
+        }
+
+        if (!empty($newHash)) {
+            $share->setPassword($newHash);
+            $provider = $this->factory->getProviderForType($share->getShareType());
+            $provider->update($share);
+        }
+
+        return true;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function userDeleted($uid) {
+        $types = [\OCP\Share::SHARE_TYPE_USER, \OCP\Share::SHARE_TYPE_GROUP, \OCP\Share::SHARE_TYPE_LINK, \OCP\Share::SHARE_TYPE_REMOTE, \OCP\Share::SHARE_TYPE_EMAIL];
+
+        foreach ($types as $type) {
+            try {
+                $provider = $this->factory->getProviderForType($type);
+            } catch (ProviderException $e) {
+                continue;
+            }
+            $provider->userDeleted($uid, $type);
+        }
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function groupDeleted($gid) {
+        $provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_GROUP);
+        $provider->groupDeleted($gid);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function userDeletedFromGroup($uid, $gid) {
+        $provider = $this->factory->getProviderForType(\OCP\Share::SHARE_TYPE_GROUP);
+        $provider->userDeletedFromGroup($uid, $gid);
+    }
+
+    /**
+     * Get access list to a path. This means
+     * all the users that can access a given path.
+     *
+     * Consider:
+     * -root
+     * |-folder1 (23)
+     *  |-folder2 (32)
+     *   |-fileA (42)
+     *
+     * fileA is shared with user1 and user1@server1
+     * folder2 is shared with group2 (user4 is a member of group2)
+     * folder1 is shared with user2 (renamed to "folder (1)") and user2@server2
+     *
+     * Then the access list to '/folder1/folder2/fileA' with $currentAccess is:
+     * [
+     *  users  => [
+     *      'user1' => ['node_id' => 42, 'node_path' => '/fileA'],
+     *      'user4' => ['node_id' => 32, 'node_path' => '/folder2'],
+     *      'user2' => ['node_id' => 23, 'node_path' => '/folder (1)'],
+     *  ],
+     *  remote => [
+     *      'user1@server1' => ['node_id' => 42, 'token' => 'SeCr3t'],
+     *      'user2@server2' => ['node_id' => 23, 'token' => 'FooBaR'],
+     *  ],
+     *  public => bool
+     *  mail => bool
+     * ]
+     *
+     * The access list to '/folder1/folder2/fileA' **without** $currentAccess is:
+     * [
+     *  users  => ['user1', 'user2', 'user4'],
+     *  remote => bool,
+     *  public => bool
+     *  mail => bool
+     * ]
+     *
+     * This is required for encryption/activity
+     *
+     * @param \OCP\Files\Node $path
+     * @param bool $recursive Should we check all parent folders as well
+     * @param bool $currentAccess Should the user have currently access to the file
+     * @return array
+     */
+    public function getAccessList(\OCP\Files\Node $path, $recursive = true, $currentAccess = false) {
+        $owner = $path->getOwner()->getUID();
+
+        if ($currentAccess) {
+            $al = ['users' => [], 'remote' => [], 'public' => false];
+        } else {
+            $al = ['users' => [], 'remote' => false, 'public' => false];
+        }
+        if (!$this->userManager->userExists($owner)) {
+            return $al;
+        }
+
+        //Get node for the owner
+        $userFolder = $this->rootFolder->getUserFolder($owner);
+        if ($path->getId() !== $userFolder->getId() && !$userFolder->isSubNode($path)) {
+            $path = $userFolder->getById($path->getId())[0];
+        }
+
+        $providers = $this->factory->getAllProviders();
+
+        /** @var Node[] $nodes */
+        $nodes = [];
+
+
+        if ($currentAccess) {
+            $ownerPath = $path->getPath();
+            $ownerPath = explode('/', $ownerPath, 4);
+            if (count($ownerPath) < 4) {
+                $ownerPath = '';
+            } else {
+                $ownerPath = $ownerPath[3];
+            }
+            $al['users'][$owner] = [
+                'node_id' => $path->getId(),
+                'node_path' => '/' . $ownerPath,
+            ];
+        } else {
+            $al['users'][] = $owner;
+        }
+
+        // Collect all the shares
+        while ($path->getPath() !== $userFolder->getPath()) {
+            $nodes[] = $path;
+            if (!$recursive) {
+                break;
+            }
+            $path = $path->getParent();
+        }
+
+        foreach ($providers as $provider) {
+            $tmp = $provider->getAccessList($nodes, $currentAccess);
+
+            foreach ($tmp as $k => $v) {
+                if (isset($al[$k])) {
+                    if (is_array($al[$k])) {
+                        $al[$k] = array_merge($al[$k], $v);
+                    } else {
+                        $al[$k] = $al[$k] || $v;
+                    }
+                } else {
+                    $al[$k] = $v;
+                }
+            }
+        }
+
+        return $al;
+    }
+
+    /**
+     * Create a new share
+     * @return \OCP\Share\IShare;
+     */
+    public function newShare() {
+        return new \OC\Share20\Share($this->rootFolder, $this->userManager);
+    }
+
+    /**
+     * Is the share API enabled
+     *
+     * @return bool
+     */
+    public function shareApiEnabled() {
+        return $this->config->getAppValue('core', 'shareapi_enabled', 'yes') === 'yes';
+    }
+
+    /**
+     * Is public link sharing enabled
+     *
+     * @return bool
+     */
+    public function shareApiAllowLinks() {
+        return $this->config->getAppValue('core', 'shareapi_allow_links', 'yes') === 'yes';
+    }
+
+    /**
+     * Is password on public link requires
+     *
+     * @return bool
+     */
+    public function shareApiLinkEnforcePassword() {
+        return $this->config->getAppValue('core', 'shareapi_enforce_links_password', 'no') === 'yes';
+    }
+
+    /**
+     * Is default expire date enabled
+     *
+     * @return bool
+     */
+    public function shareApiLinkDefaultExpireDate() {
+        return $this->config->getAppValue('core', 'shareapi_default_expire_date', 'no') === 'yes';
+    }
+
+    /**
+     * Is default expire date enforced
+     *`
+     * @return bool
+     */
+    public function shareApiLinkDefaultExpireDateEnforced() {
+        return $this->shareApiLinkDefaultExpireDate() &&
+            $this->config->getAppValue('core', 'shareapi_enforce_expire_date', 'no') === 'yes';
+    }
+
+    /**
+     * Number of default expire days
+     *shareApiLinkAllowPublicUpload
+     * @return int
+     */
+    public function shareApiLinkDefaultExpireDays() {
+        return (int)$this->config->getAppValue('core', 'shareapi_expire_after_n_days', '7');
+    }
+
+    /**
+     * Allow public upload on link shares
+     *
+     * @return bool
+     */
+    public function shareApiLinkAllowPublicUpload() {
+        return $this->config->getAppValue('core', 'shareapi_allow_public_upload', 'yes') === 'yes';
+    }
+
+    /**
+     * check if user can only share with group members
+     * @return bool
+     */
+    public function shareWithGroupMembersOnly() {
+        return $this->config->getAppValue('core', 'shareapi_only_share_with_group_members', 'no') === 'yes';
+    }
+
+    /**
+     * Check if users can share with groups
+     * @return bool
+     */
+    public function allowGroupSharing() {
+        return $this->config->getAppValue('core', 'shareapi_allow_group_sharing', 'yes') === 'yes';
+    }
+
+    /**
+     * Copied from \OC_Util::isSharingDisabledForUser
+     *
+     * TODO: Deprecate fuction from OC_Util
+     *
+     * @param string $userId
+     * @return bool
+     */
+    public function sharingDisabledForUser($userId) {
+        if ($userId === null) {
+            return false;
+        }
+
+        if (isset($this->sharingDisabledForUsersCache[$userId])) {
+            return $this->sharingDisabledForUsersCache[$userId];
+        }
+
+        if ($this->config->getAppValue('core', 'shareapi_exclude_groups', 'no') === 'yes') {
+            $groupsList = $this->config->getAppValue('core', 'shareapi_exclude_groups_list', '');
+            $excludedGroups = json_decode($groupsList);
+            if (is_null($excludedGroups)) {
+                $excludedGroups = explode(',', $groupsList);
+                $newValue = json_encode($excludedGroups);
+                $this->config->setAppValue('core', 'shareapi_exclude_groups_list', $newValue);
+            }
+            $user = $this->userManager->get($userId);
+            $usersGroups = $this->groupManager->getUserGroupIds($user);
+            if (!empty($usersGroups)) {
+                $remainingGroups = array_diff($usersGroups, $excludedGroups);
+                // if the user is only in groups which are disabled for sharing then
+                // sharing is also disabled for the user
+                if (empty($remainingGroups)) {
+                    $this->sharingDisabledForUsersCache[$userId] = true;
+                    return true;
+                }
+            }
+        }
+
+        $this->sharingDisabledForUsersCache[$userId] = false;
+        return false;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function outgoingServer2ServerSharesAllowed() {
+        return $this->config->getAppValue('files_sharing', 'outgoing_server2server_share_enabled', 'yes') === 'yes';
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function shareProviderExists($shareType) {
+        try {
+            $this->factory->getProviderForType($shareType);
+        } catch (ProviderException $e) {
+            return false;
+        }
+
+        return true;
+    }
 
 }