Shetabit\Multipay\EventEmitter

Complexity

Total Complexity

10

Size/Duplication

Total Lines	84
Duplicated Lines	0 %

Importance

Changes	1
Bugs	1	Features	0

4 Methods

Rating	Name	Duplication	Size	Complexity
A	__call()	0	3	1
A	dispatch()	0	10	2
A	addEventListener()	0	7	3
A	removeEventListener()	0	10	4

<?php

namespace Shetabit\Multipay;

class EventEmitter
{
    /**
     * List of listeners.
     *
     * @description a pair of $event => [array of listeners]
     *
     * @var array
     */
    private $listeners = [];

    /**
     * Add new listener fo given event.
     *
     * @param string $event
     * @param callable $listener
     *
     * @return void
     */
    public function addEventListener(string $event, callable $listener)
    {
        if (empty($this->listeners[$event]) || !is_array($this->listeners[$event])) {
            $this->listeners[$event] = [];
        }

        array_push($this->listeners[$event], $listener);
    }

    /**
     * Remove given listener from a specefic event.
     * if we call this method without listener, it will totaly remove the given event and all of its listeners.
     *
     * @param string $event
     * @param callable $listener
     *
     * @return void
     */
    public function removeEventListener(string $event, callable $listener = null)
    {
        if (!empty($this->listeners[$event])) {
            if (empty($listener)) { // remove the event and all of its listeners
                unset($this->listeners[$event]);
            } else {  // remove only the given listener if exists
                $listenerIndex = array_search($listener, $this->listeners[$event]);

                if ($listenerIndex !== false) {
                    unset($this->listeners[$event][$listenerIndex]);
                }
            }
        }
    }

    /**
     * Run event listeners.
     *
     * @param string $event
     * @param array ...$arguments
     *
     * @return void
     */
    public function dispatch(string $event, ...$arguments)
    {
        $listeners = $this->listeners;

        if (empty($listeners[$event])) {
            return;
        }

        array_walk($listeners[$event], function ($listener) use ($arguments) {
            call_user_func_array($listener, $arguments);
        });
    }

    /**
     * Call events by their name.
     *
     * @param string $name
     * @param array $arguments
     *
     * @return void
     */
    public function __call($name, $arguments)
    {
        $this->dispatch($name, $arguments);
    }
}