public function get_expected_data() {
        if (!$this->qa->get_state()->is_finished()) {
            return array();
        }

        $vars = array('comment' => question_attempt::PARAM_RAW_FILES, 'commentformat' => PARAM_INT);
        if ($this->qa->get_max_mark()) {
            $vars['mark'] = PARAM_RAW_TRIMMED;
            $vars['maxmark'] = PARAM_FLOAT;
        }
        return $vars;
    }