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<?php
// imports
if (!defined('NO_IMPORTS')) {
        require_once(WCF_DIR.'lib/system/auth/UserAuthDefault.class.php');
        require_once(WCF_DIR.'lib/system/event/EventHandler.class.php');
}

/**
 * All user authentication type should implement the abstract functions of this class.
 *
 * @package     com.woltlab.wcf.system.auth
 * @author      Marcel Werk
 * @copyright   2001-2007 WoltLab GmbH
 * @license     GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
 */
abstract class UserAuth {
        protected static $instance = null;

        /**
         * Returns an instance of the enabled user auth class.
         *
         * @return      UserAuth
         */
        public static function getInstance() {
                if (self::$instance === null) {
                        // call loadInstance event
                        if (!defined('NO_IMPORTS')) EventHandler::fireAction('UserAuth', 'loadInstance');

                        if (self::$instance === null) self::$instance = new UserAuthDefault();
                }
                return self::$instance;
        }

        /**
         * Returns true, if this auth type supports persistent logins.
         *
         * @return      boolean
         */
        public abstract function supportsPersistentLogins();

        /**
         * Stores the user access data for a persistent login.
         */
        public abstract function storeAccessData($user, $username, $password);

        /**
         * Does an manual user login.
         *
         * @return      User
         */
        public abstract function loginManually($username, $password, $userClassname = 'UserSession');

        /**
         * Does an automatic user login.
         *
         * @return      User
         */
        public abstract function loginAutomatically($persistent = false, $userClassname = 'UserSession');
}
?>