/app/code/core/Mage/Authorizenet/controllers/Directpost/PaymentController.php

<?php
/**
 * Magento
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Open Software License (OSL 3.0)
 * that is bundled with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://opensource.org/licenses/osl-3.0.php
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@magentocommerce.com so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade Magento to newer
 * versions in the future. If you wish to customize Magento for your
 * needs please refer to http://www.magentocommerce.com for more information.
 *
 * @category    Mage
 * @package     Mage_Authorizenet
 * @copyright   Copyright (c) 2010 Magento Inc. (http://www.magentocommerce.com)
 * @license     http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
 */

/**
 * DirtectPost Payment Controller
 *
 * @category   Mage
 * @package    Mage_Authorizenet
 * @author     Magento Core Team <core@magentocommerce.com>
 */
class Mage_Authorizenet_Directpost_PaymentController extends Mage_Core_Controller_Front_Action
{
    /**
     * @return Mage_Checkout_Model_Session
     */
    protected function _getCheckout()
    {
        return Mage::getSingleton('checkout/session');
    }

    /**
     * Get session model

     * @return Mage_Authorizenet_Model_Directpost_Session
     */
    protected function _getDirectPostSession()
    {
        return Mage::getSingleton('authorizenet/directpost_session');
    }

    /**
     * Get iframe block instance
     *
     * @return Mage_Authorizenet_Block_Directpost_Iframe
     */
    protected function _getIframeBlock()
    {
        return $this->getLayout()->createBlock('directpost/iframe');
    }

    /**
     * Response action.
     * Action for Authorize.net SIM Relay Request.
     */
    public function responseAction()
    {
        $data = $this->getRequest()->getPost();
        /* @var $paymentMethod Mage_Authorizenet_Model_DirectPost */
        $paymentMethod = Mage::getModel('authorizenet/directpost');

        $result = array();
        if (!empty($data['x_invoice_num'])) {
            $result['x_invoice_num'] = $data['x_invoice_num'];
        }

        try {
            if (!empty($data['store_id'])) {
                $paymentMethod->setStore($data['store_id']);
            }
            $paymentMethod->process($data);
            $result['success'] = 1;
        }
        catch (Mage_Core_Exception $e) {
            Mage::logException($e);
            $result['success'] = 0;
            $result['error_msg'] = $e->getMessage();
        }
        catch (Exception $e) {
            Mage::logException($e);
            $result['success'] = 0;
            $result['error_msg'] = $this->__('There was an error processing your order. Please contact us or try again later.');
        }

        if (!empty($data['controller_action_name'])) {
            if (!empty($data['key'])) {
                $result['key'] = $data['key'];
            }
            $result['controller_action_name'] = $data['controller_action_name'];
            $result['is_secure'] = isset($data['is_secure']) ? $data['is_secure'] : false;
            $params['redirect'] = Mage::helper('authorizenet')->getRedirectIframeUrl($result);
        }
        $block = $this->_getIframeBlock()->setParams($params);
        $this->getResponse()->setBody($block->toHtml());
    }

    /**
     * Retrieve params and put javascript into iframe
     *
     */
    public function redirectAction()
    {
        $redirectParams = $this->getRequest()->getParams();
        $params = array();
        if (!empty($redirectParams['success'])
            && isset($redirectParams['x_invoice_num'])
            && isset($redirectParams['controller_action_name'])
        ) {
            $this->_getDirectPostSession()->unsetData('quote_id');
            $params['redirect_parent'] = Mage::helper('authorizenet')->getSuccessOrderUrl($redirectParams);
        }
        if (!empty($redirectParams['error_msg'])) {
            $cancelOrder = empty($redirectParams['x_invoice_num']);
            $this->_returnCustomerQuote($cancelOrder, $redirectParams['error_msg']);
        }
        $block = $this->_getIframeBlock()->setParams(array_merge($params, $redirectParams));
        $this->getResponse()->setBody($block->toHtml());
    }

    /**
     * Send request to authorize.net
     *
     */
    public function placeAction()
    {
        $paymentParam = $this->getRequest()->getParam('payment');
        $controller = $this->getRequest()->getParam('controller');
        if (isset($paymentParam['method'])) {
            $params = Mage::helper('authorizenet')->getSaveOrderUrlParams($controller);
            $this->_getDirectPostSession()->setQuoteId($this->_getCheckout()->getQuote()->getId());
            $this->_forward(
                $params['action'],
                $params['controller'],
                $params['module'],
                $this->getRequest()->getParams()
            );
        } else {
            $result = array(
                'error_messages' => $this->__('Please, choose payment method'),
                'goto_section'   => 'payment'
            );
            $this->getResponse()->setBody(Mage::helper('core')->jsonEncode($result));
        }
    }

    /**
     * Return customer quote by ajax
     *
     */
    public function returnQuoteAction()
    {
        $this->_returnCustomerQuote();
        $this->getResponse()->setBody(Mage::helper('core')->jsonEncode(array('success' => 1)));
    }

    /**
     * Return customer quote
     *
     * @param bool $cancelOrder
     * @param string $errorMsg
     */
    protected function _returnCustomerQuote($cancelOrder = false, $errorMsg = '')
    {
        $incrementId = $this->_getDirectPostSession()->getLastOrderIncrementId();
        if ($incrementId &&
            $this->_getDirectPostSession()
                ->isCheckoutOrderIncrementIdExist($incrementId)
        ) {
            /* @var $order Mage_Sales_Model_Order */
            $order = Mage::getModel('sales/order')->loadByIncrementId($incrementId);
            if ($order->getId()) {
                $quote = Mage::getModel('sales/quote')
                    ->load($order->getQuoteId());
                if ($quote->getId()) {
                    $quote->setIsActive(1)
                        ->setReservedOrderId(NULL)
                        ->save();
                    $this->_getCheckout()->replaceQuote($quote);
                }
                $this->_getDirectPostSession()->removeCheckoutOrderIncrementId($incrementId);
                $this->_getDirectPostSession()->unsetData('quote_id');
                if ($cancelOrder) {
                    $order->registerCancellation($errorMsg)->save();
                }
            }
        }
    }
}