Proyectos de Subversion Moodle

<?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/>.

/**

 * Upgrade library code for the match question type.

 *

 * @package   qtype_match

 * @copyright 2010 The Open University

 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

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

/**

 * Class for converting attempt data for match questions when upgrading

 * attempts to the new question engine.

 *

 * This class is used by the code in question/engine/upgrade/upgradelib.php.

 *

 * @copyright 2010 The Open University

 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

class qtype_match_qe2_attempt_updater extends question_qtype_attempt_updater {

    protected $stems;

    protected $choices;

    protected $right;

    protected $stemorder;

    protected $choiceorder;

    protected $flippedchoiceorder;

    public function question_summary() {

        $this->stems = array();

        $this->choices = array();

        $this->right = array();

        foreach ($this->question->options->subquestions as $matchsub) {

            $ans = $matchsub->answertext;

            $key = array_search($matchsub->answertext, $this->choices);

            if ($key === false) {

                $key = $matchsub->id;

                $this->choices[$key] = $matchsub->answertext;

            }

            if ($matchsub->questiontext !== '') {

                $this->stems[$matchsub->id] = $this->to_text($matchsub->questiontext);

                $this->right[$matchsub->id] = $key;

            }

        }

        return $this->to_text($this->question->questiontext) . ' {' .

                implode('; ', $this->stems) . '} -> {' . implode('; ', $this->choices) . '}';

    }

    public function right_answer() {

        $answer = array();

        foreach ($this->stems as $key => $stem) {

            $answer[$stem] = $this->choices[$this->right[$key]];

        }

        return $this->make_summary($answer);

    }

    protected function explode_answer($answer) {

        if (!$answer) {

            return array();

        }

        $bits = explode(',', $answer);

        $selections = array();

        foreach ($bits as $bit) {

            list($stem, $choice) = explode('-', $bit);

            $selections[$stem] = $choice;

        }

        return $selections;

    }

    protected function make_summary($pairs) {

        $bits = array();

        foreach ($pairs as $stem => $answer) {

            $bits[] = $stem . ' -> ' . $answer;

        }

        return implode('; ', $bits);

    }

    protected function lookup_choice($choice) {

        foreach ($this->question->options->subquestions as $matchsub) {

            if ($matchsub->id == $choice) {

                if (array_key_exists($matchsub->id, $this->choices)) {

                    return $matchsub->id;

                } else {

                    return array_search($matchsub->answertext, $this->choices);

                }

            }

        }

        return null;

    }

    public function response_summary($state) {

        $choices = $this->explode_answer($state->answer);

        if (empty($choices)) {

            return null;

        }

        $pairs = array();

        foreach ($choices as $stemid => $choicekey) {

            if (array_key_exists($stemid, $this->stems) && $choices[$stemid]) {

                $choiceid = $this->lookup_choice($choicekey);

                if ($choiceid) {

                    $pairs[$this->stems[$stemid]] = $this->choices[$choiceid];

                } else {

                    $this->logger->log_assumption("Dealing with a place where the

                            student selected a choice that was later deleted for

                            match question {$this->question->id}");

                    $pairs[$this->stems[$stemid]] = '[CHOICE THAT WAS LATER DELETED]';

                }

            }

        }

        if ($pairs) {

            return $this->make_summary($pairs);

        } else {

            return '';

        }

    }

    public function was_answered($state) {

        $choices = $this->explode_answer($state->answer);

        foreach ($choices as $choice) {

            if ($choice) {

                return true;

            }

        }

        return false;

    }

    public function set_first_step_data_elements($state, &$data) {

        $choices = $this->explode_answer($state->answer);

        foreach ($choices as $key => $notused) {

            if (array_key_exists($key, $this->stems)) {

                $this->stemorder[] = $key;

            }

        }

        $this->choiceorder = array_keys($this->choices);

        shuffle($this->choiceorder);

        $this->flippedchoiceorder = array_combine(

                array_values($this->choiceorder), array_keys($this->choiceorder));

        $data['_stemorder'] = implode(',', $this->stemorder);

        $data['_choiceorder'] = implode(',', $this->choiceorder);

    }

    public function supply_missing_first_step_data(&$data) {

        throw new coding_exception('qtype_match_updater::supply_missing_first_step_data ' .

                'not tested');

        $data['_stemorder'] = array_keys($this->stems);

        $data['_choiceorder'] = shuffle(array_keys($this->choices));

    }

    public function set_data_elements_for_step($state, &$data) {

        $choices = $this->explode_answer($state->answer);

        foreach ($this->stemorder as $i => $key) {

            if (empty($choices[$key])) {

                $data['sub' . $i] = 0;

                continue;

            }

            $choice = $this->lookup_choice($choices[$key]);

            if (array_key_exists($choice, $this->flippedchoiceorder)) {

                $data['sub' . $i] = $this->flippedchoiceorder[$choice] + 1;

            } else {

                $data['sub' . $i] = 0;

            }

        }

    }

}