Created EventManager class

src/EventManager.php

@@ -0,0 +1,102 @@
+<?php
+
+namespace Dhii\WpEvents;
+
+use \Psr\EventManager\EventInterface;
+use \Psr\EventManager\EventManagerInterface;
+
+/**
+ * Event Manager.
+ *
+ * @author Miguel Muscat <[email protected]>
+ */
+class EventManager implements EventManagerInterface
+{
+
+    /**
+     * Constructs a new instance.
+     */
+    public function __construct()
+    {
+
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function attach($event, $callback, $priority = 10)
+    {
+        $eventObject = $this->normalizeEvent($event);
+        $numArgsToPass = $this->getCallableNumParams($callback);
+        \add_filter($eventObject->getName(), $callback, $priority, $numArgsToPass + 1);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function detach($event, $callback)
+    {
+        $eventObject = $this->normalizeEvent($event);
+        \remove_filter($eventObject->getName(), $callback);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function clearListeners($event)
+    {
+        $eventObject = $this->normalizeEvent($event);
+        \remove_all_filters($eventObject->getName());
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function trigger($event, $target = null, $argv = array())
+    {
+        $eventObject = $this->normalizeEvent($event);
+        $args = empty($argv)
+            ? array(null)
+            : $argv;
+        array_push($args, $target);
+        \apply_filters_ref_array($eventObject->getName(), $args);
+    }
+
+    /**
+     * Normalizes the given event into an Event instance.
+     * 
+     * @param EventInterfaceevent string or Event instance.
+     * @return EventInterface The event instance.
+     */
+    protected function normalizeEvent($event)
+    {
+        return ($event instanceof EventInterfacevent)
+            ? $event
+            : new Event($event);
+    }
+
+    /**
+     * Gets the number of parameters for a callable.
+     * 
+     * @param callable $callable The callable.
+     * @return integer The number of parameters.
+     */
+    protected function getCallableNumParams($callable)
+    {
+        return $this->getCallableReflection($callable)->getNumberOfParameter();
+    }
+
+    /**
+     * Gets the reflection instance for a callable.
+     * 
+     * @param callable $callable The callable.
+     * @return ReflectionFunction|ReflectionMethod The reflection instance.
+     */
+    protected function getCallableReflection($callable)
+    {
+        return is_array($callable) ? 
+            new ReflectionMethod($callable[0], $callable[1]) : 
+            new ReflectionFunction($callable);
+    }
+
+}