<?php
/**
 * OrangeHRM is a comprehensive Human Resource Management (HRM) System that captures
 * all the essential functionalities required for any enterprise.
 * Copyright (C) 2006 OrangeHRM Inc., http://www.orangehrm.com
 *
 * OrangeHRM is free software; you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * OrangeHRM 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program;
 * if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA  02110-1301, USA
 */

/**
 * Observer interface listening to event changes.
 */
interface EventObserver {

    /**
     * Register this observer with the given subject
     * 
     * TODO: Instead of EventMediator, use an interface or abstract super class
     *  
     * @param EventMediator 
     */
    public function register($subject);
    
    
    /**
     * Notify of event
     * @param String $event Event name
     * @param Array $data Array containing event specific data
     * @return boolean true if caller should continue UI flow, false if caller should exit 
     *      (typically done when observer handles the UI - eg redirecting the user to a confirmation page) 
     */
    public function notify($event, $data = array());
}