<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * Essay question definition class.
 *
 * @package    qtype
 * @subpackage essay
 * @copyright  2009 The Open University
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */


defined('MOODLE_INTERNAL') || die();


/**
 * Represents an essay question.
 *
 * @copyright  2009 The Open University
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class qtype_essay_question extends question_with_responses {
    public $responseformat;
    public $responsefieldlines;
    public $attachments;
    public $graderinfo;
    public $graderinfoformat;

    public function make_behaviour(question_attempt $qa, $preferredbehaviour) {
        question_engine::load_behaviour_class('manualgraded');
        return new qbehaviour_manualgraded($qa, $preferredbehaviour);
    }

    /**
     * @param moodle_page the page we are outputting to.
     * @return qtype_essay_format_renderer_base the response-format-specific renderer.
     */
    public function get_format_renderer(moodle_page $page) {
        return $page->get_renderer('qtype_essay', 'format_' . $this->responseformat);
    }

    public function get_expected_data() {
        if ($this->responseformat == 'editorfilepicker') {
            $expecteddata = array('answer' => question_attempt::PARAM_CLEANHTML_FILES);
        } else {
            $expecteddata = array('answer' => PARAM_CLEANHTML);
        }
        $expecteddata['answerformat'] = PARAM_ALPHANUMEXT;
        if ($this->attachments != 0) {
            $expecteddata['attachments'] = question_attempt::PARAM_FILES;
        }
        return $expecteddata;
    }

    public function summarise_response(array $response) {
        if (isset($response['answer'])) {
            $formatoptions = new stdClass();
            $formatoptions->para = false;
            return html_to_text(format_text(
                    $response['answer'], FORMAT_HTML, $formatoptions), 0, false);
        } else {
            return null;
        }
    }

    public function get_correct_response() {
        return null;
    }

    public function is_complete_response(array $response) {
        return !empty($response['answer']);
    }

    public function is_same_response(array $prevresponse, array $newresponse) {
        return question_utils::arrays_same_at_key_missing_is_blank(
                $prevresponse, $newresponse, 'answer') && ($this->attachments == 0 ||
                question_utils::arrays_same_at_key_missing_is_blank(
                $prevresponse, $newresponse, 'attachments'));
    }

    public function check_file_access($qa, $options, $component, $filearea, $args, $forcedownload) {
        if ($component == 'question' && $filearea == 'response_attachments') {
            // Response attachments visible if the question has them.
            return $this->attachments != 0;

        } else if ($component == 'question' && $filearea == 'response_answer') {
            // Response attachments visible if the question has them.
            return $this->responseformat === 'editorfilepicker';

        } else if ($component == 'qtype_essay' && $filearea == 'graderinfo') {
            return $options->manualcomment;

        } else {
            return parent::check_file_access($qa, $options, $component,
                    $filearea, $args, $forcedownload);
        }
    }
}
