<?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_AdminNotification
 * @copyright   Copyright (c) 2012 Magento Inc. (http://www.magentocommerce.com)
 * @license     http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
 */


/**
 * AdminNotification Feed model
 *
 * @category   Mage
 * @package    Mage_AdminNotification
 * @author      Magento Core Team <core@magentocommerce.com>
 */
class Mage_AdminNotification_Model_Feed extends Mage_Core_Model_Abstract
{
    const XML_USE_HTTPS_PATH    = 'system/adminnotification/use_https';
    const XML_FEED_URL_PATH     = 'system/adminnotification/feed_url';
    const XML_FREQUENCY_PATH    = 'system/adminnotification/frequency';
    const XML_LAST_UPDATE_PATH  = 'system/adminnotification/last_update';

    /**
     * Feed url
     *
     * @var string
     */
    protected $_feedUrl;

    /**
     * Init model
     *
     */
    protected function _construct()
    {}

    /**
     * Retrieve feed url
     *
     * @return string
     */
    public function getFeedUrl()
    {
        if (is_null($this->_feedUrl)) {
            $this->_feedUrl = (Mage::getStoreConfigFlag(self::XML_USE_HTTPS_PATH) ? 'https://' : 'http://')
                . Mage::getStoreConfig(self::XML_FEED_URL_PATH);
        }
        return $this->_feedUrl;
    }

    /**
     * Check feed for modification
     *
     * @return Mage_AdminNotification_Model_Feed
     */
    public function checkUpdate()
    {
        if (($this->getFrequency() + $this->getLastUpdate()) > time()) {
            return $this;
        }

        $feedData = array();

        $feedXml = $this->getFeedData();

        if ($feedXml && $feedXml->channel && $feedXml->channel->item) {
            foreach ($feedXml->channel->item as $item) {
                $feedData[] = array(
                    'severity'      => (int)$item->severity,
                    'date_added'    => $this->getDate((string)$item->pubDate),
                    'title'         => (string)$item->title,
                    'description'   => (string)$item->description,
                    'url'           => (string)$item->link,
                );
            }

            if ($feedData) {
                Mage::getModel('adminnotification/inbox')->parse(array_reverse($feedData));
            }

        }
        $this->setLastUpdate();

        return $this;
    }

    /**
     * Retrieve DB date from RSS date
     *
     * @param string $rssDate
     * @return string YYYY-MM-DD YY:HH:SS
     */
    public function getDate($rssDate)
    {
        return gmdate('Y-m-d H:i:s', strtotime($rssDate));
    }

    /**
     * Retrieve Update Frequency
     *
     * @return int
     */
    public function getFrequency()
    {
        return Mage::getStoreConfig(self::XML_FREQUENCY_PATH) * 3600;
    }

    /**
     * Retrieve Last update time
     *
     * @return int
     */
    public function getLastUpdate()
    {
        return Mage::app()->loadCache('admin_notifications_lastcheck');
//        return Mage::getStoreConfig(self::XML_LAST_UPDATE_PATH);
    }

    /**
     * Set last update time (now)
     *
     * @return Mage_AdminNotification_Model_Feed
     */
    public function setLastUpdate()
    {
        Mage::app()->saveCache(time(), 'admin_notifications_lastcheck');
//        $config = Mage::getModel('core/config');
//        /* @var $config Mage_Core_Model_Config */
//        $config->saveConfig(self::XML_LAST_UPDATE_PATH, time());
        return $this;
    }

    /**
     * Retrieve feed data as XML element
     *
     * @return SimpleXMLElement
     */
    public function getFeedData()
    {
        $curl = new Varien_Http_Adapter_Curl();
        $curl->setConfig(array(
            'timeout'   => 2
        ));
        $curl->write(Zend_Http_Client::GET, $this->getFeedUrl(), '1.0');
        $data = $curl->read();
        if ($data === false) {
            return false;
        }
        $data = preg_split('/^\r?$/m', $data, 2);
        $data = trim($data[1]);
        $curl->close();

        try {
            $xml  = new SimpleXMLElement($data);
        }
        catch (Exception $e) {
            return false;
        }

        return $xml;
    }

    public function getFeedXml()
    {
        try {
            $data = $this->getFeedData();
            $xml  = new SimpleXMLElement($data);
        }
        catch (Exception $e) {
            $xml  = new SimpleXMLElement('<?xml version="1.0" encoding="utf-8" ?>');
        }

        return $xml;
    }
}