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/>.

/**

 * Base class for rendering question types like this one.

 *

 * @package    qtype_gapselect

 * @copyright  2011 The Open University

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

 */

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

/**

 * Renders question types where the question includes embedded interactive elements.

 *

 * @copyright  2011 The Open University

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

 */

abstract class qtype_elements_embedded_in_question_text_renderer

        extends qtype_with_combined_feedback_renderer {

    public function formulation_and_controls(question_attempt $qa,

            question_display_options $options) {

        $question = $qa->get_question();

        $questiontext = '';

        // Glue question fragments together using unique placeholders, apply format_text to the result

        // and then substitute each placeholder with the embedded element.

        // This will ensure that format_text() is applied to the whole question but not to the embedded elements.

        $placeholders = $this->get_fragments_glue_placeholders($question->textfragments);

        foreach ($question->textfragments as $i => $fragment) {

            if ($i > 0) {

                $questiontext .= $placeholders[$i];

                // There is a preg_replace 11 lines ahead where the $embeddedelements is used as the replace.

                // If there are currency like options ($4) in the select then the preg_replace treats them as backreferences.

                // So we need to escape the backreferences here.

                $embeddedelements[$placeholders[$i]] =

                        preg_replace('/\$(\d)/', '\\\$$1', $this->embedded_element($qa, $i, $options));

            }

            $questiontext .= $fragment;

        }

        $questiontext = $question->format_text($questiontext,

            $question->questiontextformat, $qa, 'question', 'questiontext', $question->id);

        foreach ($placeholders as $i => $placeholder) {

            $questiontext = preg_replace('/'. preg_quote($placeholder, '/') . '/',

                $embeddedelements[$placeholder], $questiontext);

        }

        $result = '';

        $result .= html_writer::tag('div', $questiontext, array('class' => 'qtext'));

        $result .= $this->post_qtext_elements($qa, $options);

        if ($qa->get_state() == question_state::$invalid) {

            $result .= html_writer::nonempty_tag('div',

                    $question->get_validation_error($qa->get_last_qt_data()),

                    array('class' => 'validationerror'));

        }

        return $result;

    }

    /**

     * Find strings that we can use to glue the fragments with

     *

     * These strings have to be all different and neither of them can be present in the text

     *

     * @param array $fragments

     * @return array array with indexes from 1 to count($fragments)-1

     */

    protected function get_fragments_glue_placeholders($fragments) {

        $fragmentscount = count($fragments);

        if ($fragmentscount <= 1) {

            return [];

        }

        $prefix = '[[$';

        $postfix = ']]';

        $text = join('', $fragments);

        while (preg_match('/' . preg_quote($prefix, '/') . '\\d+' . preg_quote($postfix, '/') . '/', $text)) {

            $prefix .= '$';

        }

        $glues = [];

        for ($i = 1; $i < $fragmentscount; $i++) {

            $glues[$i] = $prefix . $i . $postfix;

        }

        return $glues;

    }

    protected function qtext_id($qa) {

        return str_replace(':', '_', $qa->get_qt_field_name(''));

    }

    abstract protected function embedded_element(question_attempt $qa, $place,

            question_display_options $options);

    protected function post_qtext_elements(question_attempt $qa,

            question_display_options $options) {

        return '';

    }

    protected function box_id(question_attempt $qa, $place) {

        return str_replace(':', '_', $qa->get_qt_field_name($place));

    }

    public function specific_feedback(question_attempt $qa) {

        return $this->combined_feedback($qa);

    }

    public function correct_response(question_attempt $qa) {

        $question = $qa->get_question();

        $correctanswer = '';

        foreach ($question->textfragments as $i => $fragment) {

            if ($i > 0) {

                $group = $question->places[$i];

                $choice = $question->choices[$group][$question->rightchoices[$i]];

                $correctanswer .= '[' . str_replace('-', '‑',

                        $choice->text) . ']';

            }

            $correctanswer .= $fragment;

        }

        if (!empty($correctanswer)) {

            return get_string('correctansweris', 'qtype_gapselect',

                    $question->format_text($correctanswer, $question->questiontextformat,

                            $qa, 'question', 'questiontext', $question->id));

        }

    }

}