<?php
/**
 * @author Bart Visscher <bartv@thisnet.nl>
 * @author Georg Ehrke <georg@owncloud.com>
 * @author Jörn Friedrich Dreyer <jfd@butonic.de>
 * @author Lukas Reschke <lukas@owncloud.com>
 * @author Morris Jobke <hey@morrisjobke.de>
 * @author Robin McCorkell <rmccorkell@karoshi.org.uk>
 * @author Thomas Müller <thomas.mueller@tmit.eu>
 *
 * @copyright Copyright (c) 2015, 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/>
 *
 */
OC_Hook::connect('OC_User', 'post_deleteUser', 'OC_SubAdmin', 'post_deleteUser');
OC_Hook::connect('OC_User', 'post_deleteGroup', 'OC_SubAdmin', 'post_deleteGroup');
/**
 * This class provides all methods needed for managing groups.
 *
 * Hooks provided:
 *   post_createSubAdmin($gid)
 *   post_deleteSubAdmin($gid)
 */
class OC_SubAdmin{

	/**
	 * add a SubAdmin
	 * @param string $uid uid of the SubAdmin
	 * @param string $gid gid of the group
	 * @return boolean
	 */
	public static function createSubAdmin($uid, $gid) {
		$stmt = OC_DB::prepare('INSERT INTO `*PREFIX*group_admin` (`gid`,`uid`) VALUES(?,?)');
		$result = $stmt->execute(array($gid, $uid));
		OC_Hook::emit( "OC_SubAdmin", "post_createSubAdmin", array( "gid" => $gid ));
		return true;
	}

	/**
	 * delete a SubAdmin
	 * @param string $uid uid of the SubAdmin
	 * @param string $gid gid of the group
	 * @return boolean
	 */
	public static function deleteSubAdmin($uid, $gid) {
		$stmt = OC_DB::prepare('DELETE FROM `*PREFIX*group_admin` WHERE `gid` = ? AND `uid` = ?');
		$result = $stmt->execute(array($gid, $uid));
		OC_Hook::emit( "OC_SubAdmin", "post_deleteSubAdmin", array( "gid" => $gid ));
		return true;
	}

	/**
	 * get groups of a SubAdmin
	 * @param string $uid uid of the SubAdmin
	 * @return array
	 */
	public static function getSubAdminsGroups($uid) {
		$stmt = OC_DB::prepare('SELECT `gid` FROM `*PREFIX*group_admin` WHERE `uid` = ?');
		$result = $stmt->execute(array($uid));
		$gids = array();
		while($row = $result->fetchRow()) {
			$gids[] = $row['gid'];
		}
		return $gids;
	}

	/**
	 * get SubAdmins of a group
	 * @param string $gid gid of the group
	 * @return array
	 */
	public static function getGroupsSubAdmins($gid) {
		$stmt = OC_DB::prepare('SELECT `uid` FROM `*PREFIX*group_admin` WHERE `gid` = ?');
		$result = $stmt->execute(array($gid));
		$uids = array();
		while($row = $result->fetchRow()) {
			$uids[] = $row['uid'];
		}
		return $uids;
	}

	/**
	 * get all SubAdmins
	 * @return array
	 */
	public static function getAllSubAdmins() {
		$stmt = OC_DB::prepare('SELECT * FROM `*PREFIX*group_admin`');
		$result = $stmt->execute();
		$subadmins = array();
		while($row = $result->fetchRow()) {
			$subadmins[] = $row;
		}
		return $subadmins;
	}

	/**
	 * checks if a user is a SubAdmin of a group
	 * @param string $uid uid of the subadmin
	 * @param string $gid gid of the group
	 * @return bool
	 */
	public static function isSubAdminofGroup($uid, $gid) {
		$stmt = OC_DB::prepare('SELECT COUNT(*) AS `count` FROM `*PREFIX*group_admin` WHERE `uid` = ? AND `gid` = ?');
		$result = $stmt->execute(array($uid, $gid));
		$result = $result->fetchRow();
		if($result['count'] >= 1) {
			return true;
		}
		return false;
	}

	/**
	 * checks if a user is a SubAdmin
	 * @param string $uid uid of the subadmin
	 * @return bool
	 */
	public static function isSubAdmin($uid) {
		// Check if the user is already an admin
		if(OC_Group::inGroup($uid, 'admin' )) {
			return true;
		}

		$stmt = OC_DB::prepare('SELECT COUNT(*) AS `count` FROM `*PREFIX*group_admin` WHERE `uid` = ?');
		$result = $stmt->execute(array($uid));
		$result = $result->fetchRow();
		if($result['count'] > 0) {
			return true;
		}
		return false;
	}

	/**
	 * checks if a user is a accessible by a subadmin
	 * @param string $subadmin uid of the subadmin
	 * @param string $user uid of the user
	 * @return bool
	 */
	public static function isUserAccessible($subadmin, $user) {
		if(!self::isSubAdmin($subadmin)) {
			return false;
		}
		if(OC_User::isAdminUser($user)) {
			return false;
		}
		$accessiblegroups = self::getSubAdminsGroups($subadmin);
		foreach($accessiblegroups as $accessiblegroup) {
			if(OC_Group::inGroup($user, $accessiblegroup)) {
				return true;
			}
		}
		return false;
	}

	/*
	 * alias for self::isSubAdminofGroup()
	 */
	public static function isGroupAccessible($subadmin, $group) {
		return self::isSubAdminofGroup($subadmin, $group);
	}

	/**
	 * delete all SubAdmins by uid
	 * @param array $parameters
	 * @return boolean
	 */
	public static function post_deleteUser($parameters) {
		$stmt = OC_DB::prepare('DELETE FROM `*PREFIX*group_admin` WHERE `uid` = ?');
		$result = $stmt->execute(array($parameters['uid']));
		return true;
	}

	/**
	 * delete all SubAdmins by gid
	 * @param array $parameters
	 * @return boolean
	 */
	public static function post_deleteGroup($parameters) {
		$stmt = OC_DB::prepare('DELETE FROM `*PREFIX*group_admin` WHERE `gid` = ?');
		$result = $stmt->execute(array($parameters['gid']));
		return true;
	}
}