code: public function urlDecodeUnreservedChars($string)
      {
          $string = rawurldecode($string);
          $string = rawurlencode($string);
          $string = str_replace(array( '%2F', '%3A', '%40' ), array( '/', ':', '@' ), $string);
  
          return $string;
      }
docs: Decode unreserved characters
  
  @link https://tools.ietf.org/html/rfc3986#section-2.3