<?php
  /**
   * ownCloud
   *
   * @author Georg Ehrke
   * @copyright 2012 Georg Ehrke
   *
   * 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/>.
   *
   */
  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{
  
  	/**
  	 * @brief add a SubAdmin
  	 * @param $uid uid of the SubAdmin
  	 * @param $gid gid of the group
  	 * @return boolean
  	 */
  	public static function createSubAdmin($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;
  	}
  
  	/**
  	 * @brief delete a SubAdmin
  	 * @param $uid uid of the SubAdmin
  	 * @param $gid gid of the group
  	 * @return boolean
  	 */
  	public static function deleteSubAdmin($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;
  	}
  
  	/**
  	 * @brief get groups of a SubAdmin
  	 * @param $uid uid of the SubAdmin
  	 * @return array
  	 */
  	public static function getSubAdminsGroups($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;
  	}
  
  	/**
  	 * @brief get SubAdmins of a group
  	 * @param $gid gid of the group
  	 * @return array
  	 */
  	public static function getGroupsSubAdmins($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;
  	}
  
  	/**
  	 * @brief 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;
  	}
  
  	/**
  	 * @brief checks if a user is a SubAdmin of a group
  	 * @param $uid uid of the subadmin
  	 * @param $gid gid of the group
  	 * @return bool
  	 */
  	public static function isSubAdminofGroup($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;
  	}
  
  	/**
  	 * @brief checks if a user is a SubAdmin
  	 * @param $uid uid of the subadmin
  	 * @return bool
  	 */
  	public static function isSubAdmin($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;
  	}
  
  	/**
  	 * @brief checks if a user is a accessible by a subadmin
  	 * @param $subadmin uid of the subadmin
  	 * @param $user uid of the user
  	 * @return bool
  	 */
  	public static function isUserAccessible($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;
  	}
  
  	/*
  	 * @brief alias for self::isSubAdminofGroup()
  	 */
  	public static function isGroupAccessible($subadmin, $group) {
  		return self::isSubAdminofGroup($subadmin, $group);
  	}
  
  	/**
  	 * @brief delete all SubAdmins by uid
  	 * @param $parameters
  	 * @return boolean
  	 */
  	public static function post_deleteUser($parameters) {
  		$stmt = OC_DB::prepare('DELETE FROM `*PREFIX*group_admin` WHERE `uid` = ?');
  		$result = $stmt->execute(array($parameters['uid']));
  		return true;
  	}
  
  	/**
  	 * @brief delete all SubAdmins by gid
  	 * @param $parameters
  	 * @return boolean
  	 */
  	public static function post_deleteGroup($parameters) {
  		$stmt = OC_DB::prepare('DELETE FROM `*PREFIX*group_admin` WHERE `gid` = ?');
  		$result = $stmt->execute(array($parameters['gid']));
  		return true;
  	}
  }