move the private namespace OC into lib/private - OCP will stay in lib/public

Conflicts:
	lib/private/vcategories.php

7 files changed, 1165 insertions, 0 deletions

diff --git a/lib/private/group/backend.php b/lib/private/group/backend.php
new file mode 100644
index 00000000000..2e17b5d0b7f
--- /dev/null
+++ b/lib/private/group/backend.php
@@ -0,0 +1,157 @@
+<?php
+
+/**
+* ownCloud
+*
+* @author Frank Karlitschek
+* @copyright 2012 Frank Karlitschek frank@owncloud.org
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+* License as published by the Free Software Foundation; either
+* version 3 of the License, or any later version.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+* GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+*
+* You should have received a copy of the GNU Affero General Public
+* License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+*
+*/
+
+/**
+ * error code for functions not provided by the group backend
+ */
+define('OC_GROUP_BACKEND_NOT_IMPLEMENTED',   -501);
+
+/**
+ * actions that user backends can define
+ */
+define('OC_GROUP_BACKEND_CREATE_GROUP',      0x00000001);
+define('OC_GROUP_BACKEND_DELETE_GROUP',      0x00000010);
+define('OC_GROUP_BACKEND_ADD_TO_GROUP',      0x00000100);
+define('OC_GROUP_BACKEND_REMOVE_FROM_GOUP',  0x00001000);
+define('OC_GROUP_BACKEND_GET_DISPLAYNAME',   0x00010000);
+
+/**
+ * Abstract base class for user management
+ */
+abstract class OC_Group_Backend implements OC_Group_Interface {
+	protected $possibleActions = array(
+		OC_GROUP_BACKEND_CREATE_GROUP => 'createGroup',
+		OC_GROUP_BACKEND_DELETE_GROUP => 'deleteGroup',
+		OC_GROUP_BACKEND_ADD_TO_GROUP => 'addToGroup',
+		OC_GROUP_BACKEND_REMOVE_FROM_GOUP => 'removeFromGroup',
+		OC_GROUP_BACKEND_GET_DISPLAYNAME => 'displayNamesInGroup',
+	);
+
+	/**
+	* @brief Get all supported actions
+	* @return int bitwise-or'ed actions
+	*
+	* Returns the supported actions as int to be
+	* compared with OC_USER_BACKEND_CREATE_USER etc.
+	*/
+	public function getSupportedActions() {
+		$actions = 0;
+		foreach($this->possibleActions AS $action => $methodName) {
+			if(method_exists($this, $methodName)) {
+				$actions |= $action;
+			}
+		}
+
+		return $actions;
+	}
+
+	/**
+	* @brief Check if backend implements actions
+	* @param int $actions bitwise-or'ed actions
+	* @return boolean
+	*
+	* Returns the supported actions as int to be
+	* compared with OC_GROUP_BACKEND_CREATE_GROUP etc.
+	*/
+	public function implementsActions($actions) {
+		return (bool)($this->getSupportedActions() & $actions);
+	}
+
+	/**
+	 * @brief is user in group?
+	 * @param string $uid uid of the user
+	 * @param string $gid gid of the group
+	 * @return bool
+	 *
+	 * Checks whether the user is member of a group or not.
+	 */
+	public function inGroup($uid, $gid) {
+		return in_array($gid, $this->getUserGroups($uid));
+	}
+
+	/**
+	 * @brief Get all groups a user belongs to
+	 * @param string $uid Name of the user
+	 * @return array with group names
+	 *
+	 * This function fetches all groups a user belongs to. It does not check
+	 * if the user exists at all.
+	 */
+	public function getUserGroups($uid) {
+		return array();
+	}
+
+	/**
+	 * @brief get a list of all groups
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array with group names
+	 *
+	 * Returns a list with all groups
+	 */
+
+	public function getGroups($search = '', $limit = -1, $offset = 0) {
+		return array();
+	}
+
+	/**
+	 * check if a group exists
+	 * @param string $gid
+	 * @return bool
+	 */
+	public function groupExists($gid) {
+		return in_array($gid, $this->getGroups($gid, 1));
+	}
+
+	/**
+	 * @brief get a list of all users in a group
+	 * @param string $gid
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array with user ids
+	 */
+	public function usersInGroup($gid, $search = '', $limit = -1, $offset = 0) {
+		return array();
+	}
+
+	/**
+	 * @brief get a list of all display names in a group
+	 * @param string $gid
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array with display names (value) and user ids (key)
+	 */
+	public function displayNamesInGroup($gid, $search = '', $limit = -1, $offset = 0) {
+		$displayNames = array();
+		$users = $this->usersInGroup($gid, $search, $limit, $offset);
+		foreach ($users as $user) {
+			$displayNames[$user] = $user;
+		}
+
+		return $displayNames;
+	}
+
+}
diff --git a/lib/private/group/database.php b/lib/private/group/database.php
new file mode 100644
index 00000000000..d0974685ff6
--- /dev/null
+++ b/lib/private/group/database.php
@@ -0,0 +1,239 @@
+<?php
+
+/**
+ * ownCloud
+ *
+ * @author Frank Karlitschek
+ * @copyright 2012 Frank Karlitschek frank@owncloud.org
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+/*
+ *
+ * The following SQL statement is just a help for developers and will not be
+ * executed!
+ *
+ * CREATE TABLE `groups` (
+ *   `gid` varchar(64) COLLATE utf8_unicode_ci NOT NULL,
+ *   PRIMARY KEY (`gid`)
+ * ) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
+ *
+ * CREATE TABLE `group_user` (
+ *   `gid` varchar(64) COLLATE utf8_unicode_ci NOT NULL,
+ *   `uid` varchar(64) COLLATE utf8_unicode_ci NOT NULL
+ * ) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
+ *
+ */
+
+/**
+ * Class for group management in a SQL Database (e.g. MySQL, SQLite)
+ */
+class OC_Group_Database extends OC_Group_Backend {
+
+	/**
+	 * @brief Try to create a new group
+	 * @param string $gid The name of the group to create
+	 * @return bool
+	 *
+	 * Tries to create a new group. If the group name already exists, false will
+	 * be returned.
+	 */
+	public function createGroup( $gid ) {
+		// Check for existence
+		$stmt = OC_DB::prepare( "SELECT `gid` FROM `*PREFIX*groups` WHERE `gid` = ?" );
+		$result = $stmt->execute( array( $gid ));
+
+		if( $result->fetchRow() ) {
+			// Can not add an existing group
+			return false;
+		}
+		else{
+			// Add group and exit
+			$stmt = OC_DB::prepare( "INSERT INTO `*PREFIX*groups` ( `gid` ) VALUES( ? )" );
+			$result = $stmt->execute( array( $gid ));
+
+			return $result ? true : false;
+		}
+	}
+
+	/**
+	 * @brief delete a group
+	 * @param string $gid gid of the group to delete
+	 * @return bool
+	 *
+	 * Deletes a group and removes it from the group_user-table
+	 */
+	public function deleteGroup( $gid ) {
+		// Delete the group
+		$stmt = OC_DB::prepare( "DELETE FROM `*PREFIX*groups` WHERE `gid` = ?" );
+		$stmt->execute( array( $gid ));
+
+		// Delete the group-user relation
+		$stmt = OC_DB::prepare( "DELETE FROM `*PREFIX*group_user` WHERE `gid` = ?" );
+		$stmt->execute( array( $gid ));
+
+		return true;
+	}
+
+	/**
+	 * @brief is user in group?
+	 * @param string $uid uid of the user
+	 * @param string $gid gid of the group
+	 * @return bool
+	 *
+	 * Checks whether the user is member of a group or not.
+	 */
+	public function inGroup( $uid, $gid ) {
+		// check
+		$stmt = OC_DB::prepare( "SELECT `uid` FROM `*PREFIX*group_user` WHERE `gid` = ? AND `uid` = ?" );
+		$result = $stmt->execute( array( $gid, $uid ));
+
+		return $result->fetchRow() ? true : false;
+	}
+
+	/**
+	 * @brief Add a user to a group
+	 * @param string $uid Name of the user to add to group
+	 * @param string $gid Name of the group in which add the user
+	 * @return bool
+	 *
+	 * Adds a user to a group.
+	 */
+	public function addToGroup( $uid, $gid ) {
+		// No duplicate entries!
+		if( !$this->inGroup( $uid, $gid )) {
+			$stmt = OC_DB::prepare( "INSERT INTO `*PREFIX*group_user` ( `uid`, `gid` ) VALUES( ?, ? )" );
+			$stmt->execute( array( $uid, $gid ));
+			return true;
+		}else{
+			return false;
+		}
+	}
+
+	/**
+	 * @brief Removes a user from a group
+	 * @param string $uid Name of the user to remove from group
+	 * @param string $gid Name of the group from which remove the user
+	 * @return bool
+	 *
+	 * removes the user from a group.
+	 */
+	public function removeFromGroup( $uid, $gid ) {
+		$stmt = OC_DB::prepare( "DELETE FROM `*PREFIX*group_user` WHERE `uid` = ? AND `gid` = ?" );
+		$stmt->execute( array( $uid, $gid ));
+
+		return true;
+	}
+
+	/**
+	 * @brief Get all groups a user belongs to
+	 * @param string $uid Name of the user
+	 * @return array with group names
+	 *
+	 * This function fetches all groups a user belongs to. It does not check
+	 * if the user exists at all.
+	 */
+	public function getUserGroups( $uid ) {
+		// No magic!
+		$stmt = OC_DB::prepare( "SELECT `gid` FROM `*PREFIX*group_user` WHERE `uid` = ?" );
+		$result = $stmt->execute( array( $uid ));
+
+		$groups = array();
+		while( $row = $result->fetchRow()) {
+			$groups[] = $row["gid"];
+		}
+
+		return $groups;
+	}
+
+	/**
+	 * @brief get a list of all groups
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array with group names
+	 *
+	 * Returns a list with all groups
+	 */
+	public function getGroups($search = '', $limit = null, $offset = null) {
+		$stmt = OC_DB::prepare('SELECT `gid` FROM `*PREFIX*groups` WHERE `gid` LIKE ?', $limit, $offset);
+		$result = $stmt->execute(array($search.'%'));
+		$groups = array();
+		while ($row = $result->fetchRow()) {
+			$groups[] = $row['gid'];
+		}
+		return $groups;
+	}
+
+	/**
+	 * check if a group exists
+	 * @param string $gid
+	 * @return bool
+	 */
+	public function groupExists($gid) {
+		$query = OC_DB::prepare('SELECT `gid` FROM `*PREFIX*groups` WHERE `gid` = ?');
+		$result = $query->execute(array($gid))->fetchOne();
+		if ($result) {
+			return true;
+		}
+		return false;
+	}
+
+	/**
+	 * @brief get a list of all users in a group
+	 * @param string $gid
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array with user ids
+	 */
+	public function usersInGroup($gid, $search = '', $limit = null, $offset = null) {
+		$stmt = OC_DB::prepare('SELECT `uid` FROM `*PREFIX*group_user` WHERE `gid` = ? AND `uid` LIKE ?',
+			$limit,
+			$offset);
+		$result = $stmt->execute(array($gid, $search.'%'));
+		$users = array();
+		while ($row = $result->fetchRow()) {
+			$users[] = $row['uid'];
+		}
+		return $users;
+	}
+
+	/**
+	 * @brief get a list of all display names in a group
+	 * @param string $gid
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array with display names (value) and user ids (key)
+	 */
+	public function displayNamesInGroup($gid, $search = '', $limit = -1, $offset = 0) {
+		$displayNames = array();
+
+		$stmt = OC_DB::prepare('SELECT `*PREFIX*users`.`uid`, `*PREFIX*users`.`displayname`'
+			.' FROM `*PREFIX*users`'
+			.' INNER JOIN `*PREFIX*group_user` ON `*PREFIX*group_user`.`uid` = `*PREFIX*users`.`uid`'
+			.' WHERE `gid` = ? AND `*PREFIX*group_user`.`uid` LIKE ?',
+			$limit,
+			$offset);
+		$result = $stmt->execute(array($gid, $search.'%'));
+		$users = array();
+		while ($row = $result->fetchRow()) {
+			$displayName = trim($row['displayname'], ' ');
+			$displayNames[$row['uid']] = empty($displayName) ? $row['uid'] : $displayName;
+		}
+		return $displayNames;
+	}
+}
diff --git a/lib/private/group/dummy.php b/lib/private/group/dummy.php
new file mode 100644
index 00000000000..9516fd52ff8
--- /dev/null
+++ b/lib/private/group/dummy.php
@@ -0,0 +1,160 @@
+<?php
+
+/**
+* ownCloud
+*
+* @author Frank Karlitschek
+* @copyright 2012 Frank Karlitschek frank@owncloud.org
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+* License as published by the Free Software Foundation; either
+* version 3 of the License, or any later version.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+* GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+*
+* You should have received a copy of the GNU Affero General Public
+* License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+*
+*/
+
+/**
+ * dummy group backend, does not keep state, only for testing use
+ */
+class OC_Group_Dummy extends OC_Group_Backend {
+	private $groups=array();
+	/**
+	 * @brief Try to create a new group
+	 * @param $gid The name of the group to create
+	 * @returns true/false
+	 *
+	 * Trys to create a new group. If the group name already exists, false will
+	 * be returned.
+	 */
+	public function createGroup($gid) {
+		if(!isset($this->groups[$gid])) {
+			$this->groups[$gid]=array();
+			return true;
+		}else{
+			return false;
+		}
+	}
+
+	/**
+	 * @brief delete a group
+	 * @param $gid gid of the group to delete
+	 * @returns true/false
+	 *
+	 * Deletes a group and removes it from the group_user-table
+	 */
+	public function deleteGroup($gid) {
+		if(isset($this->groups[$gid])) {
+			unset($this->groups[$gid]);
+			return true;
+		}else{
+			return false;
+		}
+	}
+
+	/**
+	 * @brief is user in group?
+	 * @param $uid uid of the user
+	 * @param $gid gid of the group
+	 * @returns true/false
+	 *
+	 * Checks whether the user is member of a group or not.
+	 */
+	public function inGroup($uid, $gid) {
+		if(isset($this->groups[$gid])) {
+			return (array_search($uid, $this->groups[$gid])!==false);
+		}else{
+			return false;
+		}
+	}
+
+	/**
+	 * @brief Add a user to a group
+	 * @param $uid Name of the user to add to group
+	 * @param $gid Name of the group in which add the user
+	 * @returns true/false
+	 *
+	 * Adds a user to a group.
+	 */
+	public function addToGroup($uid, $gid) {
+		if(isset($this->groups[$gid])) {
+			if(array_search($uid, $this->groups[$gid])===false) {
+				$this->groups[$gid][]=$uid;
+				return true;
+			}else{
+				return false;
+			}
+		}else{
+			return false;
+		}
+	}
+
+	/**
+	 * @brief Removes a user from a group
+	 * @param $uid NameUSER of the user to remove from group
+	 * @param $gid Name of the group from which remove the user
+	 * @returns true/false
+	 *
+	 * removes the user from a group.
+	 */
+	public function removeFromGroup($uid, $gid) {
+		if(isset($this->groups[$gid])) {
+			if(($index=array_search($uid, $this->groups[$gid]))!==false) {
+				unset($this->groups[$gid][$index]);
+			}else{
+				return false;
+			}
+		}else{
+			return false;
+		}
+	}
+
+	/**
+	 * @brief Get all groups a user belongs to
+	 * @param $uid Name of the user
+	 * @returns array with group names
+	 *
+	 * This function fetches all groups a user belongs to. It does not check
+	 * if the user exists at all.
+	 */
+	public function getUserGroups($uid) {
+		$groups=array();
+		$allGroups=array_keys($this->groups);
+		foreach($allGroups as $group) {
+			if($this->inGroup($uid, $group)) {
+				$groups[]=$group;
+			}
+		}
+		return $groups;
+	}
+
+	/**
+	 * @brief get a list of all groups
+	 * @returns array with group names
+	 *
+	 * Returns a list with all groups
+	 */
+	public function getGroups($search = '', $limit = -1, $offset = 0) {
+		return array_keys($this->groups);
+	}
+
+	/**
+	 * @brief get a list of all users in a group
+	 * @returns array with user ids
+	 */
+	public function usersInGroup($gid, $search = '', $limit = -1, $offset = 0) {
+		if(isset($this->groups[$gid])) {
+			return $this->groups[$gid];
+		}else{
+			return array();
+		}
+	}
+
+}
diff --git a/lib/private/group/example.php b/lib/private/group/example.php
new file mode 100644
index 00000000000..3519b9ed92f
--- /dev/null
+++ b/lib/private/group/example.php
@@ -0,0 +1,109 @@
+<?php
+
+/**
+* ownCloud
+*
+* @author Frank Karlitschek
+* @copyright 2012 Frank Karlitschek frank@owncloud.org
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+* License as published by the Free Software Foundation; either
+* version 3 of the License, or any later version.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+* GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+*
+* You should have received a copy of the GNU Affero General Public
+* License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+*
+*/
+
+/**
+ * abstract reference class for group management
+ * this class should only be used as a reference for method signatures and their descriptions
+ */
+abstract class OC_Group_Example {
+	/**
+	 * @brief Try to create a new group
+	 * @param $gid The name of the group to create
+	 * @returns true/false
+	 *
+	 * Trys to create a new group. If the group name already exists, false will
+	 * be returned.
+	 */
+	abstract public static function createGroup($gid);
+
+	/**
+	 * @brief delete a group
+	 * @param $gid gid of the group to delete
+	 * @returns true/false
+	 *
+	 * Deletes a group and removes it from the group_user-table
+	 */
+	abstract public static function deleteGroup($gid);
+
+	/**
+	 * @brief is user in group?
+	 * @param $uid uid of the user
+	 * @param $gid gid of the group
+	 * @returns true/false
+	 *
+	 * Checks whether the user is member of a group or not.
+	 */
+	abstract public static function inGroup($uid, $gid);
+
+	/**
+	 * @brief Add a user to a group
+	 * @param $uid Name of the user to add to group
+	 * @param $gid Name of the group in which add the user
+	 * @returns true/false
+	 *
+	 * Adds a user to a group.
+	 */
+	abstract public static function addToGroup($uid, $gid);
+
+	/**
+	 * @brief Removes a user from a group
+	 * @param $uid NameUSER of the user to remove from group
+	 * @param $gid Name of the group from which remove the user
+	 * @returns true/false
+	 *
+	 * removes the user from a group.
+	 */
+	abstract public static function removeFromGroup($uid, $gid);
+
+	/**
+	 * @brief Get all groups a user belongs to
+	 * @param $uid Name of the user
+	 * @returns array with group names
+	 *
+	 * This function fetches all groups a user belongs to. It does not check
+	 * if the user exists at all.
+	 */
+	abstract public static function getUserGroups($uid);
+
+	/**
+	 * @brief get a list of all groups
+	 * @returns array with group names
+	 *
+	 * Returns a list with all groups
+	 */
+	abstract public static function getGroups($search = '', $limit = -1, $offset = 0);
+
+	/**
+	 * check if a group exists
+	 * @param string $gid
+	 * @return bool
+	 */
+	abstract public function groupExists($gid);
+
+	/**
+	 * @brief get a list of all users in a group
+	 * @returns array with user ids
+	 */
+	abstract public static function usersInGroup($gid, $search = '', $limit = -1, $offset = 0);
+
+}
diff --git a/lib/private/group/group.php b/lib/private/group/group.php
new file mode 100644
index 00000000000..bcd2419b309
--- /dev/null
+++ b/lib/private/group/group.php
@@ -0,0 +1,248 @@
+<?php
+
+/**
+ * Copyright (c) 2013 Robin Appelman <icewind@owncloud.com>
+ * This file is licensed under the Affero General Public License version 3 or
+ * later.
+ * See the COPYING-README file.
+ */
+
+namespace OC\Group;
+
+class Group {
+	/**
+	 * @var string $id
+	 */
+	private $gid;
+
+	/**
+	 * @var \OC\User\User[] $users
+	 */
+	private $users;
+
+	/**
+	 * @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->users) {
+			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);
+		return $this->users;
+	}
+
+	/**
+	 * check if a user is in the group
+	 *
+	 * @param \OC\User\User $user
+	 * @return bool
+	 */
+	public function inGroup($user) {
+		foreach ($this->backends as $backend) {
+			if ($backend->inGroup($user->getUID(), $this->gid)) {
+				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, $offset);
+			if (!is_null($limit)) {
+				$limit -= count($userIds);
+			}
+			if (!is_null($offset)) {
+				$offset -= count($userIds);
+			}
+			$users += $this->getVerifiedUsers($userIds);
+			if (!is_null($limit) and $limit <= 0) {
+				return array_values($users);
+			}
+		}
+		return array_values($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, $offset = null) {
+		foreach ($this->backends as $backend) {
+			if ($backend->implementsActions(OC_GROUP_BACKEND_GET_DISPLAYNAME)) {
+				$userIds = array_keys($backend->displayNamesInGroup($this->gid, $search, $limit, $offset));
+			} else {
+				$userIds = $backend->usersInGroup($this->gid, $search, $limit, $offset);
+			}
+			if (!is_null($limit)) {
+				$limit -= count($userIds);
+			}
+			if (!is_null($offset)) {
+				$offset -= count($userIds);
+			}
+			$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() {
+		$result = false;
+		if ($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;
+	}
+
+	/**
+	 * @brief returns all the Users from an array that really exists
+	 * @param $userIds an array containing user IDs
+	 * @return an Array with the userId as Key and \OC\User\User as value
+	 */
+	private function getVerifiedUsers($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/interface.php b/lib/private/group/interface.php
new file mode 100644
index 00000000000..4ef3663837f
--- /dev/null
+++ b/lib/private/group/interface.php
@@ -0,0 +1,83 @@
+<?php
+
+/**
+ * ownCloud - group interface
+ *
+ * @author Arthur Schiwon
+ * @copyright 2012 Arthur Schiwon blizzz@owncloud.org
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+interface OC_Group_Interface {
+	/**
+	* @brief Check if backend implements actions
+	* @param int $actions bitwise-or'ed actions
+	* @return boolean
+	*
+	* Returns the supported actions as int to be
+	* compared with OC_GROUP_BACKEND_CREATE_GROUP etc.
+	*/
+	public function implementsActions($actions);
+
+	/**
+	 * @brief is user in group?
+	 * @param string $uid uid of the user
+	 * @param string $gid gid of the group
+	 * @return bool
+	 *
+	 * Checks whether the user is member of a group or not.
+	 */
+	public function inGroup($uid, $gid);
+
+	/**
+	 * @brief Get all groups a user belongs to
+	 * @param string $uid Name of the user
+	 * @return array with group names
+	 *
+	 * This function fetches all groups a user belongs to. It does not check
+	 * if the user exists at all.
+	 */
+	public function getUserGroups($uid);
+
+	/**
+	 * @brief get a list of all groups
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array with group names
+	 *
+	 * Returns a list with all groups
+	 */
+	public function getGroups($search = '', $limit = -1, $offset = 0);
+
+	/**
+	 * check if a group exists
+	 * @param string $gid
+	 * @return bool
+	 */
+	public function groupExists($gid);
+
+	/**
+	 * @brief get a list of all users in a group
+	 * @param string $gid
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array with user ids
+	 */
+	public function usersInGroup($gid, $search = '', $limit = -1, $offset = 0);
+
+}
diff --git a/lib/private/group/manager.php b/lib/private/group/manager.php
new file mode 100644
index 00000000000..bf469d51d12
--- /dev/null
+++ b/lib/private/group/manager.php
@@ -0,0 +1,169 @@
+<?php
+
+/**
+ * Copyright (c) 2013 Robin Appelman <icewind@owncloud.com>
+ * This file is licensed under the Affero General Public License version 3 or
+ * later.
+ * See the COPYING-README file.
+ */
+
+namespace OC\Group;
+
+use OC\Hooks\PublicEmitter;
+
+/**
+ * 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 {
+	/**
+	 * @var \OC_Group_Backend[] | \OC_Group_Database[] $backends
+	 */
+	private $backends = array();
+
+	/**
+	 * @var \OC\User\Manager $userManager
+	 */
+	private $userManager;
+
+	/**
+	 * @var \OC\Group\Group[]
+	 */
+	private $cachedGroups;
+
+	/**
+	 * @param \OC\User\Manager $userManager
+	 */
+	public function __construct($userManager) {
+		$this->userManager = $userManager;
+		$cache = & $this->cachedGroups;
+		$this->listen('\OC\Group', 'postDelete', function ($group) use (&$cache) {
+			/**
+			 * @var \OC\Group\Group $group
+			 */
+			unset($cache[$group->getGID()]);
+		});
+	}
+
+	/**
+	 * @param \OC_Group_Backend $backend
+	 */
+	public function addBackend($backend) {
+		$this->backends[] = $backend;
+	}
+
+	public function clearBackends() {
+		$this->backends = array();
+		$this->cachedGroups = array();
+	}
+
+	/**
+	 * @param string $gid
+	 * @return \OC\Group\Group
+	 */
+	public function get($gid) {
+		if (isset($this->cachedGroups[$gid])) {
+			return $this->cachedGroups[$gid];
+		}
+		foreach ($this->backends as $backend) {
+			if ($backend->groupExists($gid)) {
+				return $this->getGroupObject($gid);
+			}
+		}
+		return null;
+	}
+
+	protected function getGroupObject($gid) {
+		$backends = array();
+		foreach ($this->backends as $backend) {
+			if ($backend->groupExists($gid)) {
+				$backends[] = $backend;
+			}
+		}
+		$this->cachedGroups[$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 (!$gid) {
+			return false;
+		} else if ($this->groupExists($gid)) {
+			return $this->get($gid);
+		} 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, $offset);
+			if (!is_null($limit)) {
+				$limit -= count($groupIds);
+			}
+			if (!is_null($offset)) {
+				$offset -= count($groupIds);
+			}
+			foreach ($groupIds as $groupId) {
+				$groups[$groupId] = $this->getGroupObject($groupId);
+			}
+			if (!is_null($limit) and $limit <= 0) {
+				return array_values($groups);
+			}
+		}
+		return array_values($groups);
+	}
+
+	/**
+	 * @param \OC\User\User $user
+	 * @return \OC\Group\Group[]
+	 */
+	public function getUserGroups($user) {
+		$groups = array();
+		foreach ($this->backends as $backend) {
+			$groupIds = $backend->getUserGroups($user->getUID());
+			foreach ($groupIds as $groupId) {
+				$groups[$groupId] = $this->getGroupObject($groupId);
+			}
+		}
+		return array_values($groups);
+	}
+}