<?php
/**
 * Kumbia PHP Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://XXXXXXXX
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to hide@address.com so we can send you a copy immediately.
 *
 * @category   Kumbia
 * @package    Event
 * @copyright  Copyright (c) 2005-2009 Kumbia Team (http://www.kumbiaphp.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
 
/**
 * @see Hook
 */
require CORE_PATH . 'libs/event/hook.php';
 
/**
 * Implementación de Eventos
 *
 * @category  Kumbia
 * @package   Event
 * @copyright  Copyright (c) 2005-2009 Kumbia Team (http://www.kumbiaphp.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Event
{
    /**
     * Datos compartidos
     *
     * @var mixed
     **/
    public static $data = null;
    /**
     * Eventos
     *
     * @var array
     **/
    protected static $_events = array();
    /**
     * Verifica si un evento ya tiene manejador
     * 
     * @param string $event
     * @return boolean
     **/
    public static function has_handler($event)
    {
        return isset(self::$_events[$event]) && count(self::$_events[$event]);
    }
    /**
     * Enlaza un handler con un evento
     *
     * @param string $event evento
     * @param mixed $handler retrollamada
     **/
    public static function bind($event, $handler)
    {
        if(!isset(self::$_events[$event])) {
            self::$_events[$event] = array();
        }
        self::$_events[$event][] = $handler;
    }
    /**
     * Enlaza en el evento el handler2 antes del handler1
     *
     * @param string $event evento
     * @param mixed $handler1
     * @param mixed $handler2
     **/
    public static function before($event, $handler1, $handler2)
    {
        if(!isset(self::$_events[$event])) {
            self::$_events[$event] = array();
		}
        $i = array_search($handler1, self::$_events[$event]);
        if($i===false) {
            self::$_events[$event][] = $handler2;
        } else {
            Util::array_insert(self::$_events[$event], $i, $handler2);
		}
    }
    /**
     * Enlaza en el evento el handler2 despues del handler1
     *
     * @param string $event evento
     * @param mixed $handler1
     * @param mixed $handler2
     **/
    public static function after($event, $handler1, $handler2)
    {
        if(!isset(self::$_events[$event])) {
            self::$_events[$event] = array();
		}
        $i = array_search($handler1, self::$_events[$event]);
        if($i===false) {
            self::$_events[$event][] = $handler2;
        } else {
            Util::array_insert(self::$_events[$event], $i+1, $handler2);
		}
    }
    /**
     * Desenlaza los manejadores
     *
     * @param string $event evento
     * @param mixed $handler manejador
     **/
    public static function unbind($event, $handler=false)
    {
        if($handler && isset(self::$_events[$event])) {
            $i = array_search($handler, self::$_events[$event]);
            if($i!==false)
                unset(self::$_events[$event][$i]);
        } else {
            self::$_events[$event] = array();
        }
    }
    /**
     * Remplaza un handler por otro
     *
     * @param string $event evento
     * @param mixed $handler1 handler a remplazar
     * @param mixed $handler2 nuevo handler
     **/
    public static function replace($event, $handler1, $handler2)
    {
        if(isset(self::$_events[$event])) {
            $i = array_search($handler1, self::$_events[$event]);
            if($i!==false) {
                self::$_events[$event][$i] = $handler2;
                return true;
            }
        }
        return false;        
    }
    /**
     * Ejecuta los handlers asociados al evento
     *
     * @param string $event evento
     * @param array $args argumentos
     * @return mixed
     **/
    public static function trigger($event, $args = array())
    {
        $value = false;
        if(isset(self::$_events[$event])) {
            foreach(self::$_events[$event] as $handler) {
                $value = call_user_func_array($handler, $args);
            }
        }
        
        self::$data = null;
        return $value;
    }
}