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Diffstat (limited to 'vendor/sabre/event/lib/EventEmitterTrait.php')
| -rw-r--r-- | vendor/sabre/event/lib/EventEmitterTrait.php | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/vendor/sabre/event/lib/EventEmitterTrait.php b/vendor/sabre/event/lib/EventEmitterTrait.php new file mode 100644 index 000000000..257629fae --- /dev/null +++ b/vendor/sabre/event/lib/EventEmitterTrait.php @@ -0,0 +1,211 @@ +<?php + +namespace Sabre\Event; + +/** + * Event Emitter Trait + * + * This trait contains all the basic functions to implement an + * EventEmitterInterface. + * + * Using the trait + interface allows you to add EventEmitter capabilities + * without having to change your base-class. + * + * @copyright Copyright (C) 2013-2015 fruux GmbH (https://fruux.com/). + * @author Evert Pot (http://evertpot.com/) + * @license http://sabre.io/license/ Modified BSD License + */ +trait EventEmitterTrait { + + /** + * The list of listeners + * + * @var array + */ + protected $listeners = []; + + /** + * Subscribe to an event. + * + * @param string $eventName + * @param callable $callBack + * @param int $priority + * @return void + */ + function on($eventName, callable $callBack, $priority = 100) { + + if (!isset($this->listeners[$eventName])) { + $this->listeners[$eventName] = [ + true, // If there's only one item, it's sorted + [$priority], + [$callBack] + ]; + } else { + $this->listeners[$eventName][0] = false; // marked as unsorted + $this->listeners[$eventName][1][] = $priority; + $this->listeners[$eventName][2][] = $callBack; + } + + } + + /** + * Subscribe to an event exactly once. + * + * @param string $eventName + * @param callable $callBack + * @param int $priority + * @return void + */ + function once($eventName, callable $callBack, $priority = 100) { + + $wrapper = null; + $wrapper = function() use ($eventName, $callBack, &$wrapper) { + + $this->removeListener($eventName, $wrapper); + return call_user_func_array($callBack, func_get_args()); + + }; + + $this->on($eventName, $wrapper, $priority); + + } + + /** + * Emits an event. + * + * This method will return true if 0 or more listeners were succesfully + * handled. false is returned if one of the events broke the event chain. + * + * If the continueCallBack is specified, this callback will be called every + * time before the next event handler is called. + * + * If the continueCallback returns false, event propagation stops. This + * allows you to use the eventEmitter as a means for listeners to implement + * functionality in your application, and break the event loop as soon as + * some condition is fulfilled. + * + * Note that returning false from an event subscriber breaks propagation + * and returns false, but if the continue-callback stops propagation, this + * is still considered a 'successful' operation and returns true. + * + * Lastly, if there are 5 event handlers for an event. The continueCallback + * will be called at most 4 times. + * + * @param string $eventName + * @param array $arguments + * @param callback $continueCallBack + * @return bool + */ + function emit($eventName, array $arguments = [], callable $continueCallBack = null) { + + if (is_null($continueCallBack)) { + + foreach ($this->listeners($eventName) as $listener) { + + $result = call_user_func_array($listener, $arguments); + if ($result === false) { + return false; + } + } + + } else { + + $listeners = $this->listeners($eventName); + $counter = count($listeners); + + foreach ($listeners as $listener) { + + $counter--; + $result = call_user_func_array($listener, $arguments); + if ($result === false) { + return false; + } + + if ($counter > 0) { + if (!$continueCallBack()) break; + } + + } + + } + + return true; + + } + + /** + * Returns the list of listeners for an event. + * + * The list is returned as an array, and the list of events are sorted by + * their priority. + * + * @param string $eventName + * @return callable[] + */ + function listeners($eventName) { + + if (!isset($this->listeners[$eventName])) { + return []; + } + + // The list is not sorted + if (!$this->listeners[$eventName][0]) { + + // Sorting + array_multisort($this->listeners[$eventName][1], SORT_NUMERIC, $this->listeners[$eventName][2]); + + // Marking the listeners as sorted + $this->listeners[$eventName][0] = true; + } + + return $this->listeners[$eventName][2]; + + } + + /** + * Removes a specific listener from an event. + * + * If the listener could not be found, this method will return false. If it + * was removed it will return true. + * + * @param string $eventName + * @param callable $listener + * @return bool + */ + function removeListener($eventName, callable $listener) { + + if (!isset($this->listeners[$eventName])) { + return false; + } + foreach ($this->listeners[$eventName][2] as $index => $check) { + if ($check === $listener) { + unset($this->listeners[$eventName][1][$index]); + unset($this->listeners[$eventName][2][$index]); + return true; + } + } + return false; + + } + + /** + * Removes all listeners. + * + * If the eventName argument is specified, all listeners for that event are + * removed. If it is not specified, every listener for every event is + * removed. + * + * @param string $eventName + * @return void + */ + function removeAllListeners($eventName = null) { + + if (!is_null($eventName)) { + unset($this->listeners[$eventName]); + } else { + $this->listeners = []; + } + + } + +} |