/**
   * Removes garbage from user agent string
   * @param String User agent
   * @return String User agent
   */
  public static function cleanUserAgent($ua) {
    $ua = self::removeUPLinkFromUA($ua);
    // Remove serial number
    $ua = preg_replace('/\/SN\d{15}/', '/SNXXXXXXXXXXXXXXX', $ua);
    // Remove locale identifier for xx-xx
    $ua = preg_replace('/([ ;])[a-zA-Z]{2}-[a-zA-Z]{2}([ ;\)])/', '$1xx-xx$2', $ua);
    // Remove locale identifier for xx
    if (preg_match('/([ ;])[a-zA-Z]{2}([ ;\)])/', $ua, $matches)) {
      $support_languages = self::parseLanguages();
      foreach ($matches as $language) {
        if (in_array(strtolower(substr(trim($language), 0, 2)), $support_languages))
          $ua = preg_replace('/([ ;])[a-zA-Z]{2}([ ;\)])/', '$1xx-xx$2', $ua);
      }
    }
    $ua = self::normalizeBlackberry($ua);
    return $ua;
  }

  /**
   * Get the langages from header
   * @return array
   */
  public static function parseLanguages() {
    $lang = array();
    if(!array_key_exists('HTTP_ACCEPT_LANGUAGE',$_SERVER)) return $lang;
    $http_accept_lang = $_SERVER['HTTP_ACCEPT_LANGUAGE'];
    // Split possible languages into array
    $x = explode(",", $http_accept_lang);
    foreach ($x as $val) {
      //check for q-value and create associative array. No q-value means 1 by rule
      if (preg_match("/(.*);q=([0-1]{0,1}\.\d{0,4})/i", $val, $matches)) {
        $lang[] = strtolower($matches[1]);
      } else {
        $lang[] = strtolower($val);
      }
    }
    return $lang;
  }