ExecutionChain.php

<?php
/*
 * This file has its roots as part of the Mojavi package which was
 * Copyright (c) 2003 Sean Kerr. It has been incorporated into this
 * derivative work under the terms of the LGPL V2.1.
 * (http://www.gnu.org/licenses/lgpl-2.1.html)
 */

namespace Xmf\Xadr;

use Xmf\Xadr\Exceptions\RecursiveForwardException;

/**
 * ExecutionChain is a list of actions to be performed
 * The Controller establishes the ExecutionChain, while the
 * ExecutionFilter processes the chain.
 *
 * The Execution chain allows access to the state of all executed
 * actions resulting from a request.
 *
 * @category  Xmf\Xadr\ExecutionChain
 * @package   Xmf
 * @author    Richard Griffith <richard@geekwright.com>
 * @author    Sean Kerr <skerr@mojavi.org>
 * @copyright 2013-2015 XOOPS Project (http://xoops.org)
 * @copyright 2003 Sean Kerr
 * @license   GNU GPL 2 or later (http://www.gnu.org/licenses/gpl-2.0.html)
 * @link      http://xoops.org
 */
class ExecutionChain extends \SplStack
{

    /**
     * An indexed array of executed actions.
     *
     * @var array
     */
    protected $chain;

    /**
     * Create a new ExecutionChain instance.
     */
    public function __construct()
    {
        $this->chain = array();
    }

    /**
     * Add an action request to the chain.
     *
     * @param string      $unitName   A unit name.
     * @param string      $actionName An action name.
     * @param Action|null $action     An Action instance.
     *
     * @return void
     *
     * @throws RecursiveForwardException
     */
    public function addRequest($unitName, $actionName, $action)
    {
        //$this->setIteratorMode(\SplDoublyLinkedList::IT_MODE_LIFO | \SplDoublyLinkedList::IT_MODE_KEEP);
        foreach ($this as $stackReq) {
            if ($stackReq['unit_name'] == $unitName && $stackReq['action_name'] == $actionName) {
                $error = 'Recursive forward on unit ' . $unitName . ', action ' . $actionName;
                throw new RecursiveForwardException($error);
            }
        }
        $req = array(
            'unit_name'   => $unitName,
            'action_name' => $actionName,
            'action'      => $action,
            'microtime'   => microtime(true)
        );
        $this->push($req);
    }

    /**
     * Retrieve the last Action instance
     *
     * @return Action|null The Action instance of last stack entry, or null if the stack is empty
     */
    public function getAction()
    {
        try {
            $req = $this->top();
            $action = $req['action'];
        } catch (\RuntimeException $e) {
            $action = null;
        }

        return $action;
    }
}