<?php
/**
 * Part of the Joomla Framework Event Package
 *
 * @copyright  Copyright (C) 2005 - 2021 Open Source Matters, Inc. All rights reserved.
 * @license    GNU General Public License version 2 or later; see LICENSE
 */

namespace Joomla\Event;

use ArrayAccess;
use Countable;
use Serializable;

/**
 * Implementation of EventInterface.
 *
 * @since  1.0
 */
abstract class AbstractEvent implements EventInterface, ArrayAccess, Serializable, Countable
{
	/**
	 * The event name.
	 *
	 * @var    string
	 * @since  1.0
	 */
	protected $name;

	/**
	 * The event arguments.
	 *
	 * @var    array
	 * @since  1.0
	 */
	protected $arguments;

	/**
	 * A flag to see if the event propagation is stopped.
	 *
	 * @var    boolean
	 * @since  1.0
	 */
	protected $stopped = false;

	/**
	 * Constructor.
	 *
	 * @param   string  $name       The event name.
	 * @param   array   $arguments  The event arguments.
	 *
	 * @since   1.0
	 */
	public function __construct($name, array $arguments = [])
	{
		$this->name      = $name;
		$this->arguments = $arguments;
	}

	/**
	 * Get the event name.
	 *
	 * @return  string  The event name.
	 *
	 * @since   1.0
	 */
	public function getName()
	{
		return $this->name;
	}

	/**
	 * Get an event argument value.
	 *
	 * @param   string  $name     The argument name.
	 * @param   mixed   $default  The default value if not found.
	 *
	 * @return  mixed  The argument value or the default value.
	 *
	 * @since   1.0
	 */
	public function getArgument($name, $default = null)
	{
		if (isset($this->arguments[$name]))
		{
			return $this->arguments[$name];
		}

		return $default;
	}

	/**
	 * Tell if the given event argument exists.
	 *
	 * @param   string  $name  The argument name.
	 *
	 * @return  boolean  True if it exists, false otherwise.
	 *
	 * @since   1.0
	 */
	public function hasArgument($name)
	{
		return isset($this->arguments[$name]);
	}

	/**
	 * Get all event arguments.
	 *
	 * @return  array  An associative array of argument names as keys and their values as values.
	 *
	 * @since   1.0
	 */
	public function getArguments()
	{
		return $this->arguments;
	}

	/**
	 * Tell if the event propagation is stopped.
	 *
	 * @return  boolean  True if stopped, false otherwise.
	 *
	 * @since   1.0
	 */
	public function isStopped()
	{
		return $this->stopped === true;
	}

	/**
	 * Stops the propagation of the event to further event listeners.
	 *
	 * @return  void
	 *
	 * @since   2.0.0
	 */
	public function stopPropagation(): void
	{
		$this->stopped = true;
	}

	/**
	 * Count the number of arguments.
	 *
	 * @return  integer  The number of arguments.
	 *
	 * @since   1.0
	 */
	public function count()
	{
		return \count($this->arguments);
	}

	/**
	 * Serialize the event.
	 *
	 * @return  string  The serialized event.
	 *
	 * @since   1.0
	 */
	public function serialize()
	{
		return serialize($this->__serialize());
	}

	/**
	 * Serialize the event.
	 *
	 * @return  array  The data to be serialized
	 *
	 * @since   2.0.0
	 */
	public function __serialize()
	{
		return [
			'name'      => $this->name,
			'arguments' => $this->arguments,
			'stopped'   => $this->stopped,
		];
	}

	/**
	 * Unserialize the event.
	 *
	 * @param   string  $serialized  The serialized event.
	 *
	 * @return  void
	 *
	 * @since   1.0
	 */
	public function unserialize($serialized)
	{
		$this->__unserialize(unserialize($serialized));
	}

	/**
	 * Unserialize the event.
	 *
	 * @param   array  $data  The serialized event.
	 *
	 * @return  void
	 *
	 * @since   2.0.0
	 */
	public function __unserialize(array $data)
	{
		$this->name      = $data['name'];
		$this->arguments = $data['arguments'];
		$this->stopped   = $data['stopped'];
	}

	/**
	 * Tell if the given event argument exists.
	 *
	 * @param   string  $name  The argument name.
	 *
	 * @return  boolean  True if it exists, false otherwise.
	 *
	 * @since   1.0
	 */
	public function offsetExists($name)
	{
		return $this->hasArgument($name);
	}

	/**
	 * Get an event argument value.
	 *
	 * @param   string  $name  The argument name.
	 *
	 * @return  mixed  The argument value or null if not existing.
	 *
	 * @since   1.0
	 */
	public function offsetGet($name)
	{
		return $this->getArgument($name);
	}
}
