Move \OC\Group to PSR-4

3 files changed, 840 insertions, 0 deletions

diff --git a/lib/private/Group/Group.php b/lib/private/Group/Group.php
new file mode 100644
index 00000000000..064b9f899e6
--- /dev/null
+++ b/lib/private/Group/Group.php
@@ -0,0 +1,289 @@
+<?php
+/**
+ * @author Arthur Schiwon <blizzz@owncloud.com>
+ * @author Bart Visscher <bartv@thisnet.nl>
+ * @author Joas Schilling <nickvergessen@owncloud.com>
+ * @author Lukas Reschke <lukas@owncloud.com>
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Robin Appelman <icewind@owncloud.com>
+ * @author Robin McCorkell <robin@mccorkell.me.uk>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OC\Group;
+
+use OCP\IGroup;
+
+class Group implements IGroup {
+	/**
+	 * @var string $id
+	 */
+	private $gid;
+
+	/**
+	 * @var \OC\User\User[] $users
+	 */
+	private $users = array();
+
+	/**
+	 * @var bool $usersLoaded
+	 */
+	private $usersLoaded;
+
+	/**
+	 * @var \OC_Group_Backend[]|\OC_Group_Database[] $backend
+	 */
+	private $backends;
+
+	/**
+	 * @var \OC\Hooks\PublicEmitter $emitter
+	 */
+	private $emitter;
+
+	/**
+	 * @var \OC\User\Manager $userManager
+	 */
+	private $userManager;
+
+	/**
+	 * @param string $gid
+	 * @param \OC_Group_Backend[] $backends
+	 * @param \OC\User\Manager $userManager
+	 * @param \OC\Hooks\PublicEmitter $emitter
+	 */
+	public function __construct($gid, $backends, $userManager, $emitter = null) {
+		$this->gid = $gid;
+		$this->backends = $backends;
+		$this->userManager = $userManager;
+		$this->emitter = $emitter;
+	}
+
+	public function getGID() {
+		return $this->gid;
+	}
+
+	/**
+	 * get all users in the group
+	 *
+	 * @return \OC\User\User[]
+	 */
+	public function getUsers() {
+		if ($this->usersLoaded) {
+			return $this->users;
+		}
+
+		$userIds = array();
+		foreach ($this->backends as $backend) {
+			$diff = array_diff(
+				$backend->usersInGroup($this->gid),
+				$userIds
+			);
+			if ($diff) {
+				$userIds = array_merge($userIds, $diff);
+			}
+		}
+
+		$this->users = $this->getVerifiedUsers($userIds);
+		$this->usersLoaded = true;
+		return $this->users;
+	}
+
+	/**
+	 * check if a user is in the group
+	 *
+	 * @param \OC\User\User $user
+	 * @return bool
+	 */
+	public function inGroup($user) {
+		if (isset($this->users[$user->getUID()])) {
+			return true;
+		}
+		foreach ($this->backends as $backend) {
+			if ($backend->inGroup($user->getUID(), $this->gid)) {
+				$this->users[$user->getUID()] = $user;
+				return true;
+			}
+		}
+		return false;
+	}
+
+	/**
+	 * add a user to the group
+	 *
+	 * @param \OC\User\User $user
+	 */
+	public function addUser($user) {
+		if ($this->inGroup($user)) {
+			return;
+		}
+
+		if ($this->emitter) {
+			$this->emitter->emit('\OC\Group', 'preAddUser', array($this, $user));
+		}
+		foreach ($this->backends as $backend) {
+			if ($backend->implementsActions(\OC_Group_Backend::ADD_TO_GROUP)) {
+				$backend->addToGroup($user->getUID(), $this->gid);
+				if ($this->users) {
+					$this->users[$user->getUID()] = $user;
+				}
+				if ($this->emitter) {
+					$this->emitter->emit('\OC\Group', 'postAddUser', array($this, $user));
+				}
+				return;
+			}
+		}
+	}
+
+	/**
+	 * remove a user from the group
+	 *
+	 * @param \OC\User\User $user
+	 */
+	public function removeUser($user) {
+		$result = false;
+		if ($this->emitter) {
+			$this->emitter->emit('\OC\Group', 'preRemoveUser', array($this, $user));
+		}
+		foreach ($this->backends as $backend) {
+			if ($backend->implementsActions(\OC_Group_Backend::REMOVE_FROM_GOUP) and $backend->inGroup($user->getUID(), $this->gid)) {
+				$backend->removeFromGroup($user->getUID(), $this->gid);
+				$result = true;
+			}
+		}
+		if ($result) {
+			if ($this->emitter) {
+				$this->emitter->emit('\OC\Group', 'postRemoveUser', array($this, $user));
+			}
+			if ($this->users) {
+				foreach ($this->users as $index => $groupUser) {
+					if ($groupUser->getUID() === $user->getUID()) {
+						unset($this->users[$index]);
+						return;
+					}
+				}
+			}
+		}
+	}
+
+	/**
+	 * search for users in the group by userid
+	 *
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return \OC\User\User[]
+	 */
+	public function searchUsers($search, $limit = null, $offset = null) {
+		$users = array();
+		foreach ($this->backends as $backend) {
+			$userIds = $backend->usersInGroup($this->gid, $search, $limit, $offset);
+			$users += $this->getVerifiedUsers($userIds);
+			if (!is_null($limit) and $limit <= 0) {
+				return array_values($users);
+			}
+		}
+		return array_values($users);
+	}
+
+	/**
+	 * returns the number of users matching the search string
+	 *
+	 * @param string $search
+	 * @return int|bool
+	 */
+	public function count($search = '') {
+		$users = false;
+		foreach ($this->backends as $backend) {
+			if($backend->implementsActions(\OC_Group_Backend::COUNT_USERS)) {
+				if($users === false) {
+					//we could directly add to a bool variable, but this would
+					//be ugly
+					$users = 0;
+				}
+				$users += $backend->countUsersInGroup($this->gid, $search);
+			}
+		}
+		return $users;
+	}
+
+	/**
+	 * search for users in the group by displayname
+	 *
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return \OC\User\User[]
+	 */
+	public function searchDisplayName($search, $limit = null, $offset = null) {
+		$users = array();
+		foreach ($this->backends as $backend) {
+			$userIds = $backend->usersInGroup($this->gid, $search, $limit, $offset);
+			$users = $this->getVerifiedUsers($userIds);
+			if (!is_null($limit) and $limit <= 0) {
+				return array_values($users);
+			}
+		}
+		return array_values($users);
+	}
+
+	/**
+	 * delete the group
+	 *
+	 * @return bool
+	 */
+	public function delete() {
+		// Prevent users from deleting group admin
+		if ($this->getGID() === 'admin') {
+			return false;
+		}
+
+		$result = false;
+		if ($this->emitter) {
+			$this->emitter->emit('\OC\Group', 'preDelete', array($this));
+		}
+		foreach ($this->backends as $backend) {
+			if ($backend->implementsActions(\OC_Group_Backend::DELETE_GROUP)) {
+				$result = true;
+				$backend->deleteGroup($this->gid);
+			}
+		}
+		if ($result and $this->emitter) {
+			$this->emitter->emit('\OC\Group', 'postDelete', array($this));
+		}
+		return $result;
+	}
+
+	/**
+	 * returns all the Users from an array that really exists
+	 * @param string[] $userIds an array containing user IDs
+	 * @return \OC\User\User[] an Array with the userId as Key and \OC\User\User as value
+	 */
+	private function getVerifiedUsers($userIds) {
+		if (!is_array($userIds)) {
+			return array();
+		}
+		$users = array();
+		foreach ($userIds as $userId) {
+			$user = $this->userManager->get($userId);
+			if (!is_null($user)) {
+				$users[$userId] = $user;
+			}
+		}
+		return $users;
+	}
+}
diff --git a/lib/private/Group/Manager.php b/lib/private/Group/Manager.php
new file mode 100644
index 00000000000..e82a1d4f2e6
--- /dev/null
+++ b/lib/private/Group/Manager.php
@@ -0,0 +1,351 @@
+<?php
+/**
+ * @author Arthur Schiwon <blizzz@owncloud.com>
+ * @author Bart Visscher <bartv@thisnet.nl>
+ * @author Bernhard Posselt <dev@bernhard-posselt.com>
+ * @author Joas Schilling <nickvergessen@owncloud.com>
+ * @author Jörn Friedrich Dreyer <jfd@butonic.de>
+ * @author Lukas Reschke <lukas@owncloud.com>
+ * @author macjohnny <estebanmarin@gmx.ch>
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Robin Appelman <icewind@owncloud.com>
+ * @author Robin McCorkell <robin@mccorkell.me.uk>
+ * @author Roeland Jago Douma <rullzer@owncloud.com>
+ * @author Roman Kreisel <mail@romankreisel.de>
+ * @author Thomas Müller <thomas.mueller@tmit.eu>
+ * @author voxsim <Simon Vocella>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OC\Group;
+
+use OC\Hooks\PublicEmitter;
+use OCP\GroupInterface;
+use OCP\IGroupManager;
+
+/**
+ * Class Manager
+ *
+ * Hooks available in scope \OC\Group:
+ * - preAddUser(\OC\Group\Group $group, \OC\User\User $user)
+ * - postAddUser(\OC\Group\Group $group, \OC\User\User $user)
+ * - preRemoveUser(\OC\Group\Group $group, \OC\User\User $user)
+ * - postRemoveUser(\OC\Group\Group $group, \OC\User\User $user)
+ * - preDelete(\OC\Group\Group $group)
+ * - postDelete(\OC\Group\Group $group)
+ * - preCreate(string $groupId)
+ * - postCreate(\OC\Group\Group $group)
+ *
+ * @package OC\Group
+ */
+class Manager extends PublicEmitter implements IGroupManager {
+	/**
+	 * @var GroupInterface[] $backends
+	 */
+	private $backends = array();
+
+	/**
+	 * @var \OC\User\Manager $userManager
+	 */
+	private $userManager;
+
+	/**
+	 * @var \OC\Group\Group[]
+	 */
+	private $cachedGroups = array();
+
+	/**
+	 * @var \OC\Group\Group[]
+	 */
+	private $cachedUserGroups = array();
+
+	/** @var \OC\SubAdmin */
+	private $subAdmin = null;
+
+	/**
+	 * @param \OC\User\Manager $userManager
+	 */
+	public function __construct(\OC\User\Manager $userManager) {
+		$this->userManager = $userManager;
+		$cachedGroups = & $this->cachedGroups;
+		$cachedUserGroups = & $this->cachedUserGroups;
+		$this->listen('\OC\Group', 'postDelete', function ($group) use (&$cachedGroups, &$cachedUserGroups) {
+			/**
+			 * @var \OC\Group\Group $group
+			 */
+			unset($cachedGroups[$group->getGID()]);
+			$cachedUserGroups = array();
+		});
+		$this->listen('\OC\Group', 'postAddUser', function ($group) use (&$cachedUserGroups) {
+			/**
+			 * @var \OC\Group\Group $group
+			 */
+			$cachedUserGroups = array();
+		});
+		$this->listen('\OC\Group', 'postRemoveUser', function ($group) use (&$cachedUserGroups) {
+			/**
+			 * @var \OC\Group\Group $group
+			 */
+			$cachedUserGroups = array();
+		});
+	}
+
+	/**
+	 * Checks whether a given backend is used
+	 *
+	 * @param string $backendClass Full classname including complete namespace
+	 * @return bool
+	 */
+	public function isBackendUsed($backendClass) {
+		$backendClass = strtolower(ltrim($backendClass, '\\'));
+
+		foreach ($this->backends as $backend) {
+			if (strtolower(get_class($backend)) === $backendClass) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * @param \OCP\GroupInterface $backend
+	 */
+	public function addBackend($backend) {
+		$this->backends[] = $backend;
+		$this->clearCaches();
+	}
+
+	public function clearBackends() {
+		$this->backends = array();
+		$this->clearCaches();
+	}
+	
+	protected function clearCaches() {
+		$this->cachedGroups = array();
+		$this->cachedUserGroups = array();
+	}
+
+	/**
+	 * @param string $gid
+	 * @return \OC\Group\Group
+	 */
+	public function get($gid) {
+		if (isset($this->cachedGroups[$gid])) {
+			return $this->cachedGroups[$gid];
+		}
+		return $this->getGroupObject($gid);
+	}
+
+	/**
+	 * @param string $gid
+	 * @return \OCP\IGroup
+	 */
+	protected function getGroupObject($gid) {
+		$backends = array();
+		foreach ($this->backends as $backend) {
+			if ($backend->groupExists($gid)) {
+				$backends[] = $backend;
+			}
+		}
+		if (count($backends) === 0) {
+			return null;
+		}
+		$this->cachedGroups[$gid] = new Group($gid, $backends, $this->userManager, $this);
+		return $this->cachedGroups[$gid];
+	}
+
+	/**
+	 * @param string $gid
+	 * @return bool
+	 */
+	public function groupExists($gid) {
+		return !is_null($this->get($gid));
+	}
+
+	/**
+	 * @param string $gid
+	 * @return \OC\Group\Group
+	 */
+	public function createGroup($gid) {
+		if ($gid === '' || is_null($gid)) {
+			return false;
+		} else if ($group = $this->get($gid)) {
+			return $group;
+		} else {
+			$this->emit('\OC\Group', 'preCreate', array($gid));
+			foreach ($this->backends as $backend) {
+				if ($backend->implementsActions(\OC_Group_Backend::CREATE_GROUP)) {
+					$backend->createGroup($gid);
+					$group = $this->getGroupObject($gid);
+					$this->emit('\OC\Group', 'postCreate', array($group));
+					return $group;
+				}
+			}
+			return null;
+		}
+	}
+
+	/**
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return \OC\Group\Group[]
+	 */
+	public function search($search, $limit = null, $offset = null) {
+		$groups = array();
+		foreach ($this->backends as $backend) {
+			$groupIds = $backend->getGroups($search, $limit, $offset);
+			foreach ($groupIds as $groupId) {
+				$groups[$groupId] = $this->get($groupId);
+			}
+			if (!is_null($limit) and $limit <= 0) {
+				return array_values($groups);
+			}
+		}
+		return array_values($groups);
+	}
+
+	/**
+	 * @param \OC\User\User|null $user
+	 * @return \OC\Group\Group[]
+	 */
+	public function getUserGroups($user) {
+		if (is_null($user)) {
+			return [];
+		}
+		return $this->getUserIdGroups($user->getUID());
+	}
+
+	/**
+	 * @param string $uid the user id
+	 * @return \OC\Group\Group[]
+	 */
+	public function getUserIdGroups($uid) {
+		if (isset($this->cachedUserGroups[$uid])) {
+			return $this->cachedUserGroups[$uid];
+		}
+		$groups = array();
+		foreach ($this->backends as $backend) {
+			$groupIds = $backend->getUserGroups($uid);
+			if (is_array($groupIds)) {
+				foreach ($groupIds as $groupId) {
+					$groups[$groupId] = $this->get($groupId);
+				}
+			}
+		}
+		$this->cachedUserGroups[$uid] = $groups;
+		return $this->cachedUserGroups[$uid];
+	}
+
+	/**
+	 * Checks if a userId is in the admin group
+	 * @param string $userId
+	 * @return bool if admin
+	 */
+	public function isAdmin($userId) {
+		return $this->isInGroup($userId, 'admin');
+	}
+
+	/**
+	 * Checks if a userId is in a group
+	 * @param string $userId
+	 * @param string $group
+	 * @return bool if in group
+	 */
+	public function isInGroup($userId, $group) {
+		return array_key_exists($group, $this->getUserIdGroups($userId));
+	}
+
+	/**
+	 * get a list of group ids for a user
+	 * @param \OC\User\User $user
+	 * @return array with group ids
+	 */
+	public function getUserGroupIds($user) {
+		return array_map(function($value) {
+			return (string) $value;
+		}, array_keys($this->getUserGroups($user)));
+	}
+
+	/**
+	 * get a list of all display names in a group
+	 * @param string $gid
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array an array of display names (value) and user ids (key)
+	 */
+	public function displayNamesInGroup($gid, $search = '', $limit = -1, $offset = 0) {
+		$group = $this->get($gid);
+		if(is_null($group)) {
+			return array();
+		}
+
+		$search = trim($search);
+		$groupUsers = array();
+
+		if(!empty($search)) {
+			// only user backends have the capability to do a complex search for users
+			$searchOffset = 0;
+			$searchLimit = $limit * 100;
+			if($limit === -1) {
+				$searchLimit = 500;
+			}
+
+			do {
+				$filteredUsers = $this->userManager->searchDisplayName($search, $searchLimit, $searchOffset);
+				foreach($filteredUsers as $filteredUser) {
+					if($group->inGroup($filteredUser)) {
+						$groupUsers[]= $filteredUser;
+					}
+				}
+				$searchOffset += $searchLimit;
+			} while(count($groupUsers) < $searchLimit+$offset && count($filteredUsers) >= $searchLimit);
+
+			if($limit === -1) {
+				$groupUsers = array_slice($groupUsers, $offset);
+			} else {
+				$groupUsers = array_slice($groupUsers, $offset, $limit);
+			}
+		} else {
+			$groupUsers = $group->searchUsers('', $limit, $offset);
+		}
+
+		$matchingUsers = array();
+		foreach($groupUsers as $groupUser) {
+			$matchingUsers[$groupUser->getUID()] = $groupUser->getDisplayName();
+		}
+		return $matchingUsers;
+	}
+
+	/**
+	 * @return \OC\SubAdmin
+	 */
+	public function getSubAdmin() {
+		if (!$this->subAdmin) {
+			$this->subAdmin = new \OC\SubAdmin(
+				$this->userManager,
+				$this,
+				\OC::$server->getDatabaseConnection()
+			);
+		}
+
+		return $this->subAdmin;
+	}
+}
diff --git a/lib/private/Group/MetaData.php b/lib/private/Group/MetaData.php
new file mode 100644
index 00000000000..8e0866479c1
--- /dev/null
+++ b/lib/private/Group/MetaData.php
@@ -0,0 +1,200 @@
+<?php
+/**
+ * @author Arthur Schiwon <blizzz@owncloud.com>
+ * @author Joas Schilling <nickvergessen@owncloud.com>
+ * @author Lukas Reschke <lukas@owncloud.com>
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Stephan Peijnik <speijnik@anexia-it.com>
+ * @author Thomas Müller <thomas.mueller@tmit.eu>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OC\Group;
+
+use OCP\IUserSession;
+
+class MetaData {
+	const SORT_NONE = 0;
+	const SORT_USERCOUNT = 1; // May have performance issues on LDAP backends
+	const SORT_GROUPNAME = 2;
+
+	/** @var string */
+	protected $user;
+	/** @var bool */
+	protected $isAdmin;
+	/** @var array */
+	protected $metaData = array();
+	/** @var \OCP\IGroupManager */
+	protected $groupManager;
+	/** @var bool */
+	protected $sorting = false;
+	/** @var IUserSession */
+	protected $userSession;
+
+	/**
+	 * @param string $user the uid of the current user
+	 * @param bool $isAdmin whether the current users is an admin
+	 * @param \OCP\IGroupManager $groupManager
+	 * @param IUserSession $userSession
+	 */
+	public function __construct(
+			$user,
+			$isAdmin,
+			\OCP\IGroupManager $groupManager,
+			IUserSession $userSession
+			) {
+		$this->user = $user;
+		$this->isAdmin = (bool)$isAdmin;
+		$this->groupManager = $groupManager;
+		$this->userSession = $userSession;
+	}
+
+	/**
+	 * returns an array with meta data about all available groups
+	 * the array is structured as follows:
+	 * [0] array containing meta data about admin groups
+	 * [1] array containing meta data about unprivileged groups
+	 * @param string $groupSearch only effective when instance was created with
+	 * isAdmin being true
+	 * @param string $userSearch the pattern users are search for
+	 * @return array
+	 */
+	public function get($groupSearch = '', $userSearch = '') {
+		$key = $groupSearch . '::' . $userSearch;
+		if(isset($this->metaData[$key])) {
+			return $this->metaData[$key];
+		}
+
+		$adminGroups = array();
+		$groups = array();
+		$sortGroupsIndex = 0;
+		$sortGroupsKeys = array();
+		$sortAdminGroupsIndex = 0;
+		$sortAdminGroupsKeys = array();
+
+		foreach($this->getGroups($groupSearch) as $group) {
+			$groupMetaData = $this->generateGroupMetaData($group, $userSearch);
+			if (strtolower($group->getGID()) !== 'admin') {
+				$this->addEntry(
+					$groups,
+					$sortGroupsKeys,
+					$sortGroupsIndex,
+					$groupMetaData);
+			} else {
+				//admin group is hard coded to 'admin' for now. In future,
+				//backends may define admin groups too. Then the if statement
+				//has to be adjusted accordingly.
+				$this->addEntry(
+					$adminGroups,
+					$sortAdminGroupsKeys,
+					$sortAdminGroupsIndex,
+					$groupMetaData);
+			}
+		}
+
+		//whether sorting is necessary is will be checked in sort()
+		$this->sort($groups, $sortGroupsKeys);
+		$this->sort($adminGroups, $sortAdminGroupsKeys);
+
+		$this->metaData[$key] = array($adminGroups, $groups);
+		return $this->metaData[$key];
+	}
+
+	/**
+	 * sets the sort mode, see SORT_* constants for supported modes
+	 *
+	 * @param int $sortMode
+	 */
+	public function setSorting($sortMode) {
+		switch ($sortMode) {
+			case self::SORT_USERCOUNT:
+			case self::SORT_GROUPNAME:
+				$this->sorting = $sortMode;
+				break;
+
+			default:
+				$this->sorting = self::SORT_NONE;
+		}
+	}
+
+	/**
+	 * adds an group entry to the resulting array
+	 * @param array $entries the resulting array, by reference
+	 * @param array $sortKeys the sort key array, by reference
+	 * @param int $sortIndex the sort key index, by reference
+	 * @param array $data the group's meta data as returned by generateGroupMetaData()
+	 */
+	private function addEntry(&$entries, &$sortKeys, &$sortIndex, $data) {
+		$entries[] = $data;
+		if ($this->sorting === self::SORT_USERCOUNT) {
+			$sortKeys[$sortIndex] = $data['usercount'];
+			$sortIndex++;
+		} else if ($this->sorting === self::SORT_GROUPNAME) {
+			$sortKeys[$sortIndex] = $data['name'];
+			$sortIndex++;
+		}
+	}
+
+	/**
+	 * creates an array containing the group meta data
+	 * @param \OCP\IGroup $group
+	 * @param string $userSearch
+	 * @return array with the keys 'id', 'name' and 'usercount'
+	 */
+	private function generateGroupMetaData(\OCP\IGroup $group, $userSearch) {
+		return array(
+				'id' => $group->getGID(),
+				'name' => $group->getGID(),
+				'usercount' => $this->sorting === self::SORT_USERCOUNT ? $group->count($userSearch) : 0,
+			);
+	}
+
+	/**
+	 * sorts the result array, if applicable
+	 * @param array $entries the result array, by reference
+	 * @param array $sortKeys the array containing the sort keys
+	 * @param return null
+	 */
+	private function sort(&$entries, $sortKeys) {
+		if ($this->sorting === self::SORT_USERCOUNT) {
+			array_multisort($sortKeys, SORT_DESC, $entries);
+		} else if ($this->sorting === self::SORT_GROUPNAME) {
+			array_multisort($sortKeys, SORT_ASC, $entries);
+		}
+	}
+
+	/**
+	 * returns the available groups
+	 * @param string $search a search string
+	 * @return \OCP\IGroup[]
+	 */
+	protected function getGroups($search = '') {
+		if($this->isAdmin) {
+			return $this->groupManager->search($search);
+		} else {
+			$userObject = $this->userSession->getUser();
+			if($userObject !== null) {
+				$groups = $this->groupManager->getSubAdmin()->getSubAdminsGroups($userObject);
+			} else {
+				$groups = [];
+			}
+
+			return $groups;
+		}
+	}
+}