Файл: libs/flight/core/Dispatcher.php
Строк: 221
<?php
/**
* Flight: An extensible micro-framework.
*
* @copyright Copyright (c) 2011, Mike Cao <mike@mikecao.com>
* @license MIT, http://flightphp.com/license
*/
namespace flightcore;
/**
* The Dispatcher class is responsible for dispatching events. Events
* are simply aliases for class methods or functions. The Dispatcher
* allows you to hook other functions to an event that can modify the
* input parameters and/or the output.
*/
class Dispatcher {
/**
* Mapped events.
*
* @var array
*/
protected $events = array();
/**
* Method filters.
*
* @var array
*/
protected $filters = array();
/**
* Dispatches an event.
*
* @param string $name Event name
* @param array $params Callback parameters
* @return string Output of callback
*/
public function run($name, array $params = array()) {
$output = '';
// Run pre-filters
if (!empty($this->filters[$name]['before'])) {
$this->filter($this->filters[$name]['before'], $params, $output);
}
// Run requested method
$output = $this->execute($this->get($name), $params);
// Run post-filters
if (!empty($this->filters[$name]['after'])) {
$this->filter($this->filters[$name]['after'], $params, $output);
}
return $output;
}
/**
* Assigns a callback to an event.
*
* @param string $name Event name
* @param callback $callback Callback function
*/
public function set($name, $callback) {
$this->events[$name] = $callback;
}
/**
* Gets an assigned callback.
*
* @param string $name Event name
* @return callback $callback Callback function
*/
public function get($name) {
return isset($this->events[$name]) ? $this->events[$name] : null;
}
/**
* Checks if an event has been set.
*
* @param string $name Event name
* @return bool Event status
*/
public function has($name) {
return isset($this->events[$name]);
}
/**
* Clears an event. If no name is given,
* all events are removed.
*
* @param string $name Event name
*/
public function clear($name = null) {
if ($name !== null) {
unset($this->events[$name]);
unset($this->filters[$name]);
}
else {
$this->events = array();
$this->filters = array();
}
}
/**
* Hooks a callback to an event.
*
* @param string $name Event name
* @param string $type Filter type
* @param callback $callback Callback function
*/
public function hook($name, $type, $callback) {
$this->filters[$name][$type][] = $callback;
}
/**
* Executes a chain of method filters.
*
* @param array $filters Chain of filters
* @param array $params Method parameters
* @param mixed $output Method output
*/
public function filter($filters, &$params, &$output) {
$args = array(&$params, &$output);
foreach ($filters as $callback) {
$continue = $this->execute($callback, $args);
if ($continue === false) break;
}
}
/**
* Executes a callback function.
*
* @param callback $callback Callback function
* @param array $params Function parameters
* @return mixed Function results
* @throws Exception
*/
public static function execute($callback, array &$params = array()) {
if (is_callable($callback)) {
return is_array($callback) ?
self::invokeMethod($callback, $params) :
self::callFunction($callback, $params);
}
else {
throw new Exception('Invalid callback specified.');
}
}
/**
* Calls a function.
*
* @param string $func Name of function to call
* @param array $params Function parameters
* @return mixed Function results
*/
public static function callFunction($func, array &$params = array()) {
switch (count($params)) {
case 0:
return $func();
case 1:
return $func($params[0]);
case 2:
return $func($params[0], $params[1]);
case 3:
return $func($params[0], $params[1], $params[2]);
case 4:
return $func($params[0], $params[1], $params[2], $params[3]);
case 5:
return $func($params[0], $params[1], $params[2], $params[3], $params[4]);
default:
return call_user_func_array($func, $params);
}
}
/**
* Invokes a method.
*
* @param mixed $func Class method
* @param array $params Class method parameters
* @return mixed Function results
*/
public static function invokeMethod($func, array &$params = array()) {
list($class, $method) = $func;
$instance = is_object($class);
switch (count($params)) {
case 0:
return ($instance) ?
$class->$method() :
$class::$method();
case 1:
return ($instance) ?
$class->$method($params[0]) :
$class::$method($params[0]);
case 2:
return ($instance) ?
$class->$method($params[0], $params[1]) :
$class::$method($params[0], $params[1]);
case 3:
return ($instance) ?
$class->$method($params[0], $params[1], $params[2]) :
$class::$method($params[0], $params[1], $params[2]);
case 4:
return ($instance) ?
$class->$method($params[0], $params[1], $params[2], $params[3]) :
$class::$method($params[0], $params[1], $params[2], $params[3]);
case 5:
return ($instance) ?
$class->$method($params[0], $params[1], $params[2], $params[3], $params[4]) :
$class::$method($params[0], $params[1], $params[2], $params[3], $params[4]);
default:
return call_user_func_array($func, $params);
}
}
/**
* Resets the object to the initial state.
*/
public function reset() {
$this->events = array();
$this->filters = array();
}
}