dispatcher.php
286 lines
| 1 | <?php |
| 2 | /** |
| 3 | * @package VikWP - Libraries |
| 4 | * @subpackage adapter.event |
| 5 | * @author E4J s.r.l. |
| 6 | * @copyright Copyright (C) 2023 E4J s.r.l. All Rights Reserved. |
| 7 | * @license http://www.gnu.org/licenses/gpl-2.0.html GNU/GPL |
| 8 | * @link https://vikwp.com |
| 9 | */ |
| 10 | |
| 11 | // No direct access |
| 12 | defined('ABSPATH') or die('No script kiddies please!'); |
| 13 | |
| 14 | JLoader::import('adapter.event.event'); |
| 15 | |
| 16 | /** |
| 17 | * Class to handle dispatching of events. |
| 18 | * |
| 19 | * @since 10.1.11 |
| 20 | */ |
| 21 | class JEventDispatcher |
| 22 | { |
| 23 | /** |
| 24 | * Stores the singleton instance of the dispatcher. |
| 25 | * |
| 26 | * @var JEventDispatcher |
| 27 | */ |
| 28 | protected static $instance = null; |
| 29 | |
| 30 | /** |
| 31 | * A list of observed classes. |
| 32 | * |
| 33 | * @var string |
| 34 | */ |
| 35 | protected $observers = array(); |
| 36 | |
| 37 | /** |
| 38 | * Returns the global Event Dispatcher object, only creating it |
| 39 | * if it doesn't already exist. |
| 40 | * |
| 41 | * @return JEventDispatcher The EventDispatcher object. |
| 42 | */ |
| 43 | public static function getInstance() |
| 44 | { |
| 45 | if (self::$instance === null) |
| 46 | { |
| 47 | self::$instance = new static(); |
| 48 | } |
| 49 | |
| 50 | return self::$instance; |
| 51 | } |
| 52 | |
| 53 | /** |
| 54 | * Triggers an event by dispatching arguments to all observers that handle |
| 55 | * the event and returning their return values. |
| 56 | * |
| 57 | * @param string $event The event to trigger. |
| 58 | * @param array $args An array of arguments. |
| 59 | * |
| 60 | * @return array An array of results from each called function. |
| 61 | */ |
| 62 | public function trigger($event, $args = array()) |
| 63 | { |
| 64 | // make sure we are passing an array of arguments |
| 65 | $args = (array) $args; |
| 66 | |
| 67 | // Push an empty value at the beginning of the list for being |
| 68 | // manipulated at every execution of the filter. |
| 69 | array_unshift($args, null); |
| 70 | |
| 71 | /** |
| 72 | * Check whether the specified event uses the Joomla notation. |
| 73 | * In that case, rebuild the event to look more similar to |
| 74 | * WordPress hooks. |
| 75 | * |
| 76 | * @since 10.1.32 |
| 77 | */ |
| 78 | if (preg_match("/^on[A-Z]/", $event)) |
| 79 | { |
| 80 | $bc = $event; |
| 81 | |
| 82 | // obtain WP hook version |
| 83 | $event = $this->getHook($event); |
| 84 | |
| 85 | // check whether someone is using a deprecated hook |
| 86 | if (has_filter($bc)) |
| 87 | { |
| 88 | // trigger warning to inform the user that a manual adjustment is needed |
| 89 | trigger_error( |
| 90 | sprintf('expected <b>%s</b> hook, <b>%s</b> given', $event, $bc), |
| 91 | E_USER_WARNING |
| 92 | ); |
| 93 | |
| 94 | /** |
| 95 | * Trigger the event for backward compatibility. |
| 96 | * Assign the returned value to the first argument, |
| 97 | * so that other plugins assigned to the correct |
| 98 | * hook will be able to manipulate it. |
| 99 | * |
| 100 | * @since 10.1.32 |
| 101 | * |
| 102 | * @deprecated 10.2 Use the correct hook instead. |
| 103 | */ |
| 104 | $args[0] = apply_filters_ref_array($bc, $args); |
| 105 | } |
| 106 | } |
| 107 | |
| 108 | /** |
| 109 | * Trigger the event. |
| 110 | * Use `apply_filters_ref_array` instead of `do_action_ref_array` |
| 111 | * to start supporting return values. |
| 112 | * |
| 113 | * @since 10.1.23 |
| 114 | */ |
| 115 | $return = apply_filters_ref_array($event, $args); |
| 116 | |
| 117 | if (is_null($return)) |
| 118 | { |
| 119 | // return an empty list as none manipulated the return value |
| 120 | return array(); |
| 121 | } |
| 122 | |
| 123 | // push the returned value within a list for Joomla standards |
| 124 | return array($return); |
| 125 | } |
| 126 | |
| 127 | /** |
| 128 | * Registers an event handler to the event dispatcher |
| 129 | * |
| 130 | * @param string $event Name of the event to register handler for. |
| 131 | * @param string $handler Name of the event handler. |
| 132 | * |
| 133 | * @return void |
| 134 | * |
| 135 | * @since 10.1.30 |
| 136 | * @throws InvalidArgumentException |
| 137 | */ |
| 138 | public function register($event, $handler) |
| 139 | { |
| 140 | // are we dealing with a class or callback type handler? |
| 141 | if (is_callable($handler)) |
| 142 | { |
| 143 | // function type event handler, let's attach it |
| 144 | $method = array('event' => $event, 'handler' => $handler); |
| 145 | $this->attach($method); |
| 146 | } |
| 147 | else if (class_exists($handler)) |
| 148 | { |
| 149 | // class type event handler, let's instantiate and attach it |
| 150 | $this->attach(new $handler($this)); |
| 151 | } |
| 152 | else |
| 153 | { |
| 154 | throw new InvalidArgumentException('Invalid event handler.'); |
| 155 | } |
| 156 | } |
| 157 | |
| 158 | /** |
| 159 | * Attach an observer object. |
| 160 | * |
| 161 | * @param mixed $observer An observer object to attach. |
| 162 | * |
| 163 | * @return void |
| 164 | * |
| 165 | * @since 10.1.29 |
| 166 | */ |
| 167 | public function attach($observer) |
| 168 | { |
| 169 | if (is_array($observer)) |
| 170 | { |
| 171 | if (!isset($observer['handler']) || !isset($observer['event']) || !is_callable($observer['handler'])) |
| 172 | { |
| 173 | return; |
| 174 | } |
| 175 | |
| 176 | // make sure we haven't already attached this array as an observer |
| 177 | foreach ($this->observers as $check) |
| 178 | { |
| 179 | if (is_array($check) && $check['event'] === $observer['event'] && $check['handler'] === $observer['handler']) |
| 180 | { |
| 181 | // callback already registered |
| 182 | return; |
| 183 | } |
| 184 | } |
| 185 | |
| 186 | // obtain callback reflection and retrieve arguments |
| 187 | $reflection = new ReflectionFunction($observer['handler']); |
| 188 | $params = $reflection->getParameters(); |
| 189 | |
| 190 | // Register filter. |
| 191 | // Always increase parameters counter by one in order to |
| 192 | // accept the return value, which is never passed on Joomla. |
| 193 | add_filter($observer['event'], $observer['handler'], 10, count($params) + 1); |
| 194 | } |
| 195 | else |
| 196 | { |
| 197 | // make sure we haven't already attached this object as an observer |
| 198 | $class = get_class($observer); |
| 199 | |
| 200 | foreach ($this->observers as $check) |
| 201 | { |
| 202 | if ($check instanceof $class) |
| 203 | { |
| 204 | // class already observed |
| 205 | return; |
| 206 | } |
| 207 | } |
| 208 | |
| 209 | // obtain class reflection |
| 210 | $reflection = new ReflectionClass($observer); |
| 211 | |
| 212 | // retrieve all methods |
| 213 | $methods = $reflection->getMethods(); |
| 214 | |
| 215 | // retrieve all JEvent methods |
| 216 | $default = get_class_methods('JEvent'); |
| 217 | |
| 218 | foreach ($methods as $method) |
| 219 | { |
| 220 | // make sure the method is not already used by the parent class, |
| 221 | // it is public and it is not static |
| 222 | if (!in_array($method->name, $default) && $method->isPublic() && !$method->isStatic()) |
| 223 | { |
| 224 | // get method parameters |
| 225 | $params = $method->getParameters(); |
| 226 | |
| 227 | /** |
| 228 | * Refactor event name at runtime to support the |
| 229 | * WordPress hooks notation. |
| 230 | * |
| 231 | * @since 10.1.32 |
| 232 | */ |
| 233 | $hook = $this->getHook($method->name); |
| 234 | |
| 235 | // Register filter. |
| 236 | // Always increase parameters counter by one in order to |
| 237 | // accept the return value, which is never passed on Joomla. |
| 238 | add_filter($hook, array($observer, $method->name), 10, count($params) + 1); |
| 239 | } |
| 240 | } |
| 241 | } |
| 242 | |
| 243 | // cache observer to avoid registering the same events more than once |
| 244 | $this->observers[] = $observer; |
| 245 | } |
| 246 | |
| 247 | /** |
| 248 | * Checks whether the specified event uses the Joomla notation. |
| 249 | * In that case, rebuild the event to look more similar to |
| 250 | * WordPress hooks. |
| 251 | * |
| 252 | * @param string $event The event to check. |
| 253 | * |
| 254 | * @return string The modified event, if needed. |
| 255 | * |
| 256 | * @since 10.1.32 |
| 257 | */ |
| 258 | protected function getHook($event) |
| 259 | { |
| 260 | // make sure it starts with "on" |
| 261 | if (preg_match("/^on[A-Z]/", $event)) |
| 262 | { |
| 263 | // remove initial "on" |
| 264 | $event = preg_replace("/^on/", '', $event); |
| 265 | |
| 266 | // recover option from request |
| 267 | $option = JFactory::getApplication()->input->get('option'); |
| 268 | |
| 269 | if ($option) |
| 270 | { |
| 271 | // clean "com_" from option |
| 272 | $option = preg_replace("/^com_/", '', $option); |
| 273 | // remove plugin name from event |
| 274 | $event = preg_replace("/{$option}/i", '', $event); |
| 275 | // always prepend plugin name at the beginning |
| 276 | $event = strtolower($option) . $event; |
| 277 | } |
| 278 | |
| 279 | // place an underscore between each camelCase |
| 280 | $event = strtolower(preg_replace("/([a-z])([A-Z])/", '$1_$2', $event)); |
| 281 | } |
| 282 | |
| 283 | return $event; |
| 284 | } |
| 285 | } |
| 286 |