Sindbad~EG File Manager

<?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/>.

/**
 * @package    moodlecore
 * @subpackage backup-moodle2
 * @copyright  2010 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */


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


/**
 * restore plugin class that provides the necessary information
 * needed to restore one random qtype plugin
 *
 * @copyright  2010 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class restore_qtype_random_plugin extends restore_qtype_plugin {

    /**
     * Define the plugin structure.
     *
     * @return array  Array of {@link restore_path_elements}.
     */
    protected function define_question_plugin_structure() {
        $paths = array();

        // We have to specify a path here if we want after_execute_question to be called.
        $elename = 'donothing';
        $elepath = $this->get_pathfor('/');

        $paths[] = new restore_path_element($elename, $elepath);

        return $paths; // And we return the interesting paths.
    }

    /**
     * Required function to process path. Should never be called.
     *
     * @param object $data Data elements.
     */
    public function process_donothing($data) {
        // Intentionally blank.
    }

    /**
     * Given one question_states record, return the answer
     * recoded pointing to all the restored stuff for random questions
     *
     * answer format is randomxx-yy, with xx being question->id and
     * yy the actual response to the question. We'll delegate the recode
     * to the corresponding qtype
     *
     * also, some old states can contain, simply, one question->id,
     * support them, just in case
     */
    public function recode_legacy_state_answer($state) {
        global $DB;

        $answer = $state->answer;
        $result = '';
        // Randomxx-yy answer format.
        if (preg_match('~^random([0-9]+)-(.*)$~', $answer, $matches)) {
            $questionid = $matches[1];
            $subanswer  = $matches[2];
            $newquestionid = $this->get_mappingid('question', $questionid);
            $questionqtype = $DB->get_field('question', 'qtype', array('id' => $newquestionid));
            // Delegate subanswer recode to proper qtype, faking one question_states record.
            $substate = new stdClass();
            $substate->question = $newquestionid;
            $substate->answer = $subanswer;
            $newanswer = $this->step->restore_recode_legacy_answer($substate, $questionqtype);
            $result = 'random' . $newquestionid . '-' . $newanswer;

            // Simple question id format.
        } else {
            $newquestionid = $this->get_mappingid('question', $answer);
            $result = $newquestionid;
        }
        return $result;
    }

    /**
     * After restoring, make sure questiontext is set properly.
     */
    public function after_execute_question() {
        global $DB;

        // For random questions, questiontext should only ever be '0' or '1'.
        // In the past there were sometimes junk values like ''. If there
        // were any in the restore, fix them up.
        //
        // Note, we cannot just do this in one DB query, because MySQL is useless.
        // The expected case is that the SELECT returns 0 rows, so loading all the
        // ids should not be a problem.
        $problemquestions = $DB->get_records_sql_menu("
                SELECT q.id, 1
                  FROM {question} q
                  JOIN {backup_ids_temp} bi ON q.id = bi.newitemid
                 WHERE q.qtype = 'random'
                   AND " . $DB->sql_compare_text('q.questiontext') . " = ?
                   AND bi.backupid = ?
                   AND bi.itemname = 'question_created'
                ", array('', $this->get_restoreid()));

        if (!$problemquestions) {
            return; // Nothing to do.
        }

        list($idtest, $params) = $DB->get_in_or_equal(array_keys($problemquestions));
        $DB->set_field_select('question', 'questiontext', '0', "id $idtest", $params);
    }
}