/**
     * Select limited stories where they are less than the given timestamp
     *
     * @param  int       $limit
     * @param  int       $timestamp
     * @param  Mongo_ID  $category
     * @return array
     */
    public function select_stories($limit, $timestamp, $category = null)
    {
        $where = array('timestamp' => array('$lt' => $timestamp), 'status' => 1);

        if(!is_null($category))
        {
            $where += array('category_id' => $category);
        }

        $stories = $this->find($where)->sort(array('timestamp' => '-1'))->limit($limit);

        return $this->build_stories_data($stories);
    }

    public function build_stories_data($stories)
    {
        $tags = $data = $categories = $users = $domains = array();
        $count = 0;

        foreach($stories as $row)
        {
            $data[$count] = $row;
            $data[$count]['tags'] = array();

            /* Build story tags */
            foreach($row['tags'] as $tag)
            {
                $tag_key = (string) $tag;

                if(!isset($tags[$tag_key]))
                {
                    $tags[$tag_key] = \Tag::instance()->get(array('_id' => $tag), array('tag', 'link'));
                }

                $data[$count]['tags'][] = $tags[$tag_key];
            }

            /* Build Category */
            $category = (string) $row['category_id'];

            if(!isset($categories[$category]))
            {
                $categories[$category] = \Category::instance()->get(array('_id' => $row['category_id']), array('category', 'link'));
            }

            $data[$count]['category'] = $categories[(string) $row['category_id']];

            /* Build user */
            $user = (string) $row['user_id'];

            if(!isset($users[$user]))
            {
                $users[$user] = \User::instance()->get(array('_id' => $row['user_id']), array('username', 'username_link'));
            }

            /* Build domain */
            $domain = (string) $row['domain_id'];

            if(!isset($domains[$domain]))
            {
                $domains[$domain] = \Domain::instance()->get(array('_id' => $row['domain_id']), array('domain', 'link'));
            }

            $data[$count]['domain'] = $domains[$domain];

            /* Build Votes */
            if(!isset($row['votes']))
            {
                $data[$count]['votes'] = array(
                    'ratio' => 0
                );
            }

            $count++;
        }

        return $data;
    }