<?php
/**
 * ownCloud
 *
 * @author Frank Karlitschek
 * @copyright 2010 Frank Karlitschek karlitschek@kde.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/>.
 *
 */

if( !$CONFIG_INSTALLED ){
	$_SESSION['user_id'] = '';
}

/**
 * This class provides all methods for user management.
 */
class OC_USER {
	// The backend used for user management
	private static $_backend = null;

	// Backends available (except database)
	private static $_backends = array();

	/**
	 * @brief registers backend
	 * @param $name name of the backend
	 * @returns true/false
	 *
	 * Makes a list of backends that can be used by other modules
	 */
	public static function registerBackend( $name ){
		self::$_backends[] = $name;
		return true;
	}

	/**
	 * @brief gets available backends
	 * @returns array of backends
	 *
	 * Returns the names of all backends.
	 */
	public static function getBackends(){
		return self::$_backends;
	}

	/**
	 * @brief Sets the backend
	 * @param $backend default: database The backend to use for user managment
	 * @returns true/false
	 *
	 * Set the User Authentication Module
	 */
	public static function setBackend( $backend = 'database' ){
		// You'll never know what happens
		if( null === $backend OR !is_string( $backend )){
			$backend = 'database';
		}

		// Load backend
		switch( $backend ){
			case 'database':
			case 'mysql':
			case 'sqlite':
				require_once('User/database.php');
				self::$_backend = new OC_USER_DATABASE();
				break;
			default:
				$className = 'OC_USER_' . strToUpper($backend);
				self::$_backend = new $className();
				break;
		}

		true;
	}

	/**
	 * @brief Creates a new user
	 * @param $username The username of the user to create
	 * @param $password The password of the new user
	 */
	public static function createUser( $username, $password ){
		return self::$_backend->createUser( $username, $password );
	}

	/**
	 * @brief try to login a user
	 * @param $username The username of the user to log in
	 * @param $password The password of the user
	 */
	public static function login( $username, $password ){
		return self::$_backend->login( $username, $password );
	}

	/**
	 * @brief Kick the user
	 */
	public static function logout(){
		return self::$_backend->logout();
	}

	/**
	 * @brief Check if the user is logged in
	 */
	public static function isLoggedIn(){
		return self::$_backend->isLoggedIn();
	}

	/**
	 * @brief Generate a random password
	 */
	public static function generatePassword(){
		return substr( md5( uniqId().time()), 0, 10 );
	}

	/**
	 * @brief Set the password of a user
	 * @param $username User whose password will be changed
	 * @param $password The new password for the user
	 */
	public static function setPassword( $username, $password ){
		return self::$_backend->setPassword( $username, $password );
	}

	/**
	 * @brief Check if the password of the user is correct
	 * @param  string  $username  Name of the user
	 * @param  string  $password  Password of the user
	 */
	public static function checkPassword( $username, $password ){
		return self::$_backend->checkPassword( $username, $password );
	}

	/**
	 * @brief get a list of all users
	 * @returns array with uids
	 */
	public static function getUsers(){
		return self::$_backend->getUsers();
	}
}