<?php
/**
 * @version     $Id$
 * @package  Wordbridge
 * @copyright   Copyright (C) 2011 Cognidox Ltd
 * @license  GNU AFFERO GENERAL PUBLIC LICENSE v3
 */

// no direct access
defined('_JEXEC') or die('Restricted access');
if(!defined('DS')) define('DS', DIRECTORY_SEPARATOR);
class WordbridgeHelper {

    /**
     * getTotalBlogPosts
     * @return int the total number of blog posts for the blog
     */
    public static function getBlogInfo($blogname = null, $useStored = false)
    {
        $info = array('count' => 0,
                      'description' => '',
                      'last_post_id' => 0,
                      'updated' => 0,
                      'last_post' => '',
                      'name' => '',
                      'uuid' => '',
                      'id' => '');

        if ($blogname == null)
        {
            $app = JFactory::getApplication();
            $params = $app->getParams();
            $blogname = $params->get('wordbridge_blog_name');
        }
        if (empty($blogname) || !function_exists('curl_init'))
        {
            return $info;
        }
        $info['name'] = $blogname;
        $stored_blog = WordbridgeHelper::getBlogByName($blogname);
        if ($stored_blog && $useStored)
        {
            return $stored_blog;
        }
        if ($stored_blog)
        {
            $info['uuid'] = $stored_blog['uuid'];
        }
        else
        {
            $info['uuid'] = uniqid();
        }

        // Only use the twitter API for blogs hosted at wordpress.com
        $fqdn = WordbridgeHelper::fqdnBlogName($blogname);
        if (substr($fqdn, -14) == '.wordpress.com')
        {
            $url = sprintf('http://twitter-api.wordpress.com/users/show.xml?screen_name=%s', urlencode($fqdn));
            $curl = curl_init();
            curl_setopt($curl, CURLOPT_URL, $url);

            $xml = WordbridgeHelper::curl_redir_exec($curl);
            curl_close($curl);
            if (empty($xml))
            {
                return $info;
            }

            $doc = new DOMDocument();
            $doc->loadXML($xml);
            $info['count'] = $doc->getElementsByTagName('statuses_count')->item(0)->textContent;
            $info['description'] = $doc->getElementsByTagName('description')->item(0)->textContent;
            $info['id'] = $doc->getElementsByTagName('id')->item(0)->textContent;

            // Get the last post information, removing the blog ID that
            // comes out when using the twitter API
            $info['last_post_id'] = $doc->getElementsByTagName('status')->item(0)->getElementsByTagName('id')->item(0)->textContent;
            $info['last_post_id'] = (int)substr($info['last_post_id'], strlen($info['id']));
            $info['last_post'] = $doc->getElementsByTagName('status')->item(0)->getElementsByTagName('text')->item(0)->textContent;
        }
        else
        {
            $url = sprintf('http://%s/?feed=wordbridge', $fqdn);
            $curl = curl_init();
            curl_setopt($curl, CURLOPT_URL, $url);

            $xml = WordbridgeHelper::curl_redir_exec($curl);
            curl_close($curl);
            if (empty($xml))
            {
                return $info;
            }

            $doc = new DOMDocument();
            $doc->loadXML($xml);

            $info['count'] = $doc->getElementsByTagName('count')->item(0)->textContent;
            $info['description'] = $doc->getElementsByTagName('description')->item(0)->textContent;
            $info['id'] = $doc->getElementsByTagName('id')->item(0)->textContent;
            // Get the last post information
            $info['last_post_id'] = $doc->getElementsByTagName('last_post_id')->item(0)->textContent;
            $info['last_post'] = $doc->getElementsByTagName('last_post')->item(0)->textContent;
        }

        // Update the stored blog basic details if need be
        if (!empty($info['description']))
        {
            if ($stored_blog)
            {
                if ($stored_blog['description'] != $info['description'] ||
                    $stored_blog['name'] != $blogname ||
                    $stored_blog['last_post'] != $info['last_post'])
                {
                    WordbridgeHelper::storeBlog($info['id'], $info['uuid'], $blogname, $info['description'], $info['last_post']);
                }
            }
            else
            {
                // Store the blog data locally
                WordbridgeHelper::storeBlog($info['id'], $info['uuid'], $blogname, $info['description'], $info['last_post']);
            }
        }
        return $info;
    }

    /**
     * getBlogByID
     * Look up the locally stored blog details
     * @return array containing id and description if found, or null if not
     */
    function getBlogByID($uuid)
    {
        $db = JFactory::getDBO();
        $query = sprintf('SELECT blog_id, blog_uuid, blog_name, description, last_post, UNIX_TIMESTAMP(updated) FROM #__com_wordbridge_blogs WHERE blog_uuid = %s LIMIT 1', $db->quote($uuid, true));
        $db->setQuery($query);
        $blog = $db->loadRow();
        if ($blog == null)
        {
            return null;
        }
        return array('id' => $blog[0], 
                     'uuid' => $blog[1],
                     'name' => $blog[2],
                     'description' => $blog[3],
                     'last_post' => $blog[4],
                     'updated' => $blog[5]);
    }

    /**
     * getBlogByName
     * Look up the locally stored blog details by name
     * @return array containing id, name and description if found, or null if not
     */
    public static function getBlogByName($name)
    {
        $db = JFactory::getDBO();
        $query = sprintf('SELECT blog_id, blog_uuid, blog_name, description, last_post, UNIX_TIMESTAMP(updated) FROM #__com_wordbridge_blogs WHERE blog_name = %s LIMIT 1', $db->quote($name, true));
        $db->setQuery($query);
        $blog = $db->loadRow();
        if ($blog == null)
        {
            return null;
        }
        return array('id' => $blog[0], 
                     'uuid' => $blog[1],
                     'name' => $blog[2],
                     'description' => $blog[3],
                     'last_post' => $blog[4],
                     'updated' => $blog[5]);
    }

    /**
     * storeBlog
     * Store the ID, name and description of a blog
     */
    public static function storeBlog($id, $uuid, $name, $description, $last_post)
    {
        $db = JFactory::getDBO();
        $query = sprintf('REPLACE INTO #__com_wordbridge_blogs VALUES(%d, %s, %s, %s, %s, NOW())', (int) $id, $db->quote($uuid, true), $db->quote($name, true), $db->quote($description, true), $db->quote($last_post, true));
        $db->setQuery($query);
        $db->execute();
    }

    public static function nameToSlug($name)
    {
        $name = trim($name);
        $name = preg_replace('/[\.\s]/', '-', $name);
        $name = preg_replace('/[^\-A-Za-z0-9]/', '', $name);
        $name = preg_replace('/--+/', '-', $name);
        $name = preg_replace('/^-|_$/', '', $name);
        return $name;
    }

    public static function storeBlogEntries($entries, $blog_uuid)
    {
        if ($entries == null)
        {
            return false;
        }
        $db = JFactory::getDBO();
        foreach ($entries as $entry)
        {
            // Update the locally cached post
            $post_query = sprintf( 
                'REPLACE INTO #__com_wordbridge_posts VALUES (%d, %s, %s, %s, %s, %s)', 
                $entry['postid'],
                $db->quote($blog_uuid, true),
                $db->quote($entry['title'], true),
                $db->quote($entry['content'], true),
                $db->quote(JFactory::getDate($entry['date'])->format('Y-m-d H:i:s T'), true),
                $db->quote($entry['slug'], true));
            $db->setQuery($post_query);
            $db->execute();

            // Update the post category settings
            $db->setQuery(sprintf('DELETE FROM #__com_wordbridge_post_categories WHERE post_id = %d AND blog_uuid = %s', $entry['postid'], $db->quote($blog_uuid, true)));
            $db->execute();
            if (count($entry['categories']))
            {
                $i = 0;
                foreach ($entry['categories'] as $category)
                {
                    $post_category_query =  sprintf('INSERT INTO #__com_wordbridge_post_categories VALUES (%d, %s, %d, %s)', $entry['postid'], $db->quote($blog_uuid, true), $i, $db->quote($category, true));
                    $db->setQuery($post_category_query);
                    $db->execute();
                    $i++;
                }
            }
        }
    }

    public static function getEntriesFromUrl($url)
    {
        // Use curl to get the data
        $curl = curl_init();
        curl_setopt($curl, CURLOPT_URL, $url);

        $xml = WordbridgeHelper::curl_redir_exec($curl);
        curl_close($curl);
        if (empty($xml))
        {
            return array();
        }

        $results = array();
        $doc = new DOMDocument();
        $doc->loadXML($xml);
        $entries = $doc->getElementsByTagName('item');
        foreach ($entries as $item)
        {
            $title = $item->getElementsByTagName('title')->item(0)->textContent;
            // Some blogs don't have a title - so try the description with
            // tags stripped out
            if (empty($title))
            {
                $title = $item->getElementsByTagName('description')->item(0)->textContent;
                $title = strip_tags($title);
                if (strlen($title) > 60)
                {
                    $title = substr($title, 0, 59) . '...';
                }
            }

            $date = $item->getElementsByTagName('pubDate')->item(0)->textContent;
            $content = $item->getElementsByTagNameNS('http://purl.org/rss/1.0/modules/content/', 'encoded')->item(0)->textContent;

            // Work out the wordpress ID for this blog entry
            // Looks like older blogs use a different format where the
            // post id is not in the guid.
            $postid = null;
            $guid = $item->getElementsByTagName('guid')->item(0)->textContent;
            if (strpos($guid, 'p=') !== false)
            {
                $guid_parts = explode('p=', $guid);
                if (count($guid_parts) == 2)
                {
                    $postid = $guid_parts[1];
                }
            }
            else
            {
                // Lookup the post id in the description, as that contains
                // a link to the stats
                $desc = $guid = $item->getElementsByTagName('description')->item(0)->textContent;
                $matches = array();
                if (preg_match('/stats\.wordpress\.com\/b.gif[^"]+post=(\d+)/',  $desc, $matches))
                {
                    $postid = $matches[1];
                }
            }

            // Enumerate the wordpress categories for this entry
            $categories = array();
            foreach ($item->getElementsByTagName('category') as $category)
            {
                $categories[] = $category->textContent;
            }

            // Get the human readable slug for this entry (may need for SEF)
            $slug = '';
            $feed_link = $item->getElementsByTagName('link')->item(0)->textContent;
            if (!empty($feed_link))
            {
                $link_parts = explode('/', $feed_link);
                $slug = $link_parts[count($link_parts) - 2];
            }

            // Add the new entry to our blog entry list
            $results[] = array('title' => $title,
                               'postid' => $postid,
                               'categories' => $categories,
                               'slug' => $slug,
                               'date' => JFactory::getDate( $date )->toUnix(),
                               'content' => $content);
        }
        return $results;
    }

    /**
     * getWordbridgeMenuIDs
     * Return a list of menu IDs for Wordbridge items
     */
    public static function getWordbridgeMenuIDs()
    {
        $result = array();
        $db = JFactory::getDBO();
        $query = "SELECT m.id FROM #__menu AS m LEFT JOIN #__extensions AS e ON m.component_id = e.extension_id WHERE e.name = 'com_wordbridge' and m.published = 1";
        $db->setQuery($query);
        $menuIDs = $db->loadRowList();
        if ($menuIDs != null && count($menuIDs))
        {
            foreach ($menuIDs as $mid)
            {
                $result[] = $mid[0];
            }
        }
        return $result;
    }

    /**
     * addTag
     * Store something as a tag
     */
    public static function addTag($blog_uuid, $name)
    {
        $db = JFactory::getDBO();
        $query = sprintf('REPLACE INTO #__com_wordbridge_blog_tags VALUES (%s, %s)', $db->quote($blog_uuid, true), $db->quote($name, true));
        $db->setQuery($query);
        $db->execute();
    }

    /**
     * addCategory
     * Store something as a category
     */
    public static function addCategory($blog_uuid, $name)
    {
        $db = JFactory::getDBO();
        $query = sprintf('REPLACE INTO #__com_wordbridge_blog_categories VALUES (%s, %s)', $db->quote($blog_uuid, true), $db->quote($name, true));
        $db->setQuery($query);
        $db->execute();
    }

    /**
     * isCategory
     * Determine if something is a Category
     * @return boolean
     */
    public static function isCategory($blog_uuid, $name)
    {
        $db = JFactory::getDBO();
        $query = sprintf('SELECT COUNT(*) FROM #__com_wordbridge_blog_categories WHERE blog_uuid = %s AND category = %s', $db->quote($blog_uuid, true), $db->quote($name, true));
        $db->setQuery($query);
        $catCount = $db->loadResult();
        
        if ($catCount)
        {
            return true;
        }
        return false;
    }

    /**
     * isTag
     * Determine if something is a tag
     * @return boolean
     */
    public static function isTag($blog_uuid, $name)
    {
        $db = JFactory::getDBO();
        $query = sprintf('SELECT COUNT(*) FROM #__com_wordbridge_blog_tags WHERE blog_uuid = %s AND tag = %s', $db->quote($blog_uuid, true), $db->quote($name, true));
        $db->setQuery($query);
        $tagCount = $db->loadResult();
        if ($tagCount)
        {
            return true;
        }
        return false;
    }

    /**
     * curl_redir_exec
     * Work around safe_mode restrictions on CURLOPT_FOLLOWLOCATION
     * Taken from http://php.net/manual/en/function.curl-setopt.php#71313
     * eion at bigfoot.com
     */
    protected static function curl_redir_exec($ch, $curl_loops = 0)
    {
        static $curl_max_loops = 20;
        if ($curl_loops++ >= $curl_max_loops)
        {
            return false;
        }
        curl_setopt($ch, CURLOPT_HEADER, true);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        $data = curl_exec($ch);

        # avoid 'Undefined offset 1' error when we only get $header
        $outputList = preg_split('/(?:\r?\n){2}/', $data, 2);
        if (count($outputList) == 2)
        {
            list($header, $data) = $outputList;
        }
        else
        {
            $header = $outputList[0];
        }

        $http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        if ($http_code == 301 || $http_code == 302)
        {
            $matches = array();
            preg_match('/Location:(.*?)(?:\n|$)/', $header, $matches);
            $url = parse_url(trim(array_pop($matches)));
            if (!$url)
            {
                //couldn't process the url to redirect to
                return $data;
            }
            $last_url = parse_url(curl_getinfo($ch, CURLINFO_EFFECTIVE_URL));
            if (!$url['scheme'])
                $url['scheme'] = $last_url['scheme'];
            if (!$url['host'])
                $url['host'] = $last_url['host'];
            if (!$url['path'])
                $url['path'] = $last_url['path'];
            $new_url = $url['scheme'] . '://' . $url['host'] . $url['path'] . (array_key_exists('query', $url) ? '?' . $url['query'] : '');
            curl_setopt($ch, CURLOPT_URL, $new_url);
            return WordbridgeHelper::curl_redir_exec($ch, $curl_loops);
        }
        else
        {
            return $data;
        }
    }

    /**
     * fqdnBlogName
     * Turns a blog name into a fully qualified hostname that can be
     * used in URLs. This will assume things without a '.' are 
     * hosted on wordpress.com, while others are full hostnames
     */
    public static function fqdnBlogName($name)
    {
        $name = trim($name) ;
        if (strpos($name, '.') == false)
        {
            return sprintf('%s.wordpress.com', strtolower($name));
        }

        if ( strpos($name, '/') != false )
        {
            list($fqdn, $subdir) = explode('/', $name, 2);
            $name = sprintf('%s/%s', strtolower($fqdn), $subdir);
        }
        else
        {
            $name = strtolower($name);
        }
        return $name;
    }

    /**
     * wordBridgeStrftime
     * Returns cross platform date formatting
     */
    public static function wordBridgeStrftime($format, $time = null, $local = false)
    {
        if (strtoupper(substr(PHP_OS, 0, 3)) == 'WIN')
        {
            $mapping = array(
                '%n' => '\n',
                '%t' => "\t",
                '%h' => '%b',
                '%e' => '%#d',
                '%P' => '%p',
                '%r' => '%I:%M:%S %p',
                '%R' => '%H:%M',
                '%T' => '%H:%M:%S',
                '%F' => '%Y-%m-%d',
                '%D' => '%m/%d/%y');
            $format = str_replace(array_keys($mapping), array_values($mapping), $format);
        }
        return JFactory::getDate($time)->format($format, $local);
    }
}