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/>.

/**

 * Matching question definition class.

 *

 * @package   qtype_match

 * @copyright 2009 The Open University

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

 */

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

require_once($CFG->dirroot . '/question/type/questionbase.php');

/**

 * Represents a matching question.

 *

 * @copyright 2009 The Open University

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

 */

class qtype_match_question extends question_graded_automatically_with_countback {

    /** @var boolean Whether the question stems should be shuffled. */

    public $shufflestems;

    public $correctfeedback;

    public $correctfeedbackformat;

    public $partiallycorrectfeedback;

    public $partiallycorrectfeedbackformat;

    public $incorrectfeedback;

    public $incorrectfeedbackformat;

    /** @var array of question stems. */

    public $stems;

    /** @var int[] FORMAT_... type for each stem. */

    public $stemformat;

    /** @var array of choices that can be matched to each stem. */

    public $choices;

    /** @var array index of the right choice for each stem. */

    public $right;

    /** @var array shuffled stem indexes. */

    protected $stemorder;

    /** @var array shuffled choice indexes. */

    protected $choiceorder;

    public function start_attempt(question_attempt_step $step, $variant) {

        $this->stemorder = array_keys($this->stems);

        if ($this->shufflestems) {

            shuffle($this->stemorder);

        }

        $step->set_qt_var('_stemorder', implode(',', $this->stemorder));

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

        shuffle($choiceorder);

        $step->set_qt_var('_choiceorder', implode(',', $choiceorder));

        $this->set_choiceorder($choiceorder);

    }

    public function apply_attempt_state(question_attempt_step $step) {

        $this->stemorder = explode(',', $step->get_qt_var('_stemorder'));

        $this->set_choiceorder(explode(',', $step->get_qt_var('_choiceorder')));

        // Add any missing subquestions. Sometimes people edit questions after they

        // have been attempted which breaks things.

        foreach ($this->stemorder as $stemid) {

            if (!isset($this->stems[$stemid])) {

                $this->stems[$stemid] = html_writer::span(

                        get_string('deletedsubquestion', 'qtype_match'), 'notifyproblem');

                $this->stemformat[$stemid] = FORMAT_HTML;

                $this->right[$stemid] = 0;

            }

        }

        // Add any missing choices. Sometimes people edit questions after they

        // have been attempted which breaks things.

        foreach ($this->choiceorder as $choiceid) {

            if (!isset($this->choices[$choiceid])) {

                $this->choices[$choiceid] = get_string('deletedchoice', 'qtype_match');

            }

        }

    }

    /**

     * Helper method used by both {@link start_attempt()} and

     * {@link apply_attempt_state()}.

     * @param array $choiceorder the choices, in order.

     */

    protected function set_choiceorder($choiceorder) {

        $this->choiceorder = array();

        foreach ($choiceorder as $key => $choiceid) {

            $this->choiceorder[$key + 1] = $choiceid;

        }

    }

    public function validate_can_regrade_with_other_version(question_definition $otherversion): ?string {

        $basemessage = parent::validate_can_regrade_with_other_version($otherversion);

        if ($basemessage) {

            return $basemessage;

        }

        if (count($this->stems) != count($otherversion->stems)) {

            return get_string('regradeissuenumstemschanged', 'qtype_match');

        }

        if (count($this->choices) != count($otherversion->choices)) {

            return get_string('regradeissuenumchoiceschanged', 'qtype_match');

        }

        return null;

    }

    public function update_attempt_state_data_for_new_version(

            question_attempt_step $oldstep, question_definition $otherversion) {

        $startdata = parent::update_attempt_state_data_for_new_version($oldstep, $otherversion);

        // Process stems.

        $mapping = array_combine(array_keys($otherversion->stems), array_keys($this->stems));

        $oldstemorder = explode(',', $oldstep->get_qt_var('_stemorder'));

        $newstemorder = [];

        foreach ($oldstemorder as $oldid) {

            $newstemorder[] = $mapping[$oldid] ?? $oldid;

        }

        $startdata['_stemorder'] = implode(',', $newstemorder);

        // Process choices.

        $mapping = array_combine(array_keys($otherversion->choices), array_keys($this->choices));

        $oldchoiceorder = explode(',', $oldstep->get_qt_var('_choiceorder'));

        $newchoiceorder = [];

        foreach ($oldchoiceorder as $oldid) {

            $newchoiceorder[] = $mapping[$oldid] ?? $oldid;

        }

        $startdata['_choiceorder'] = implode(',', $newchoiceorder);

        return $startdata;

    }

    public function get_question_summary() {

        $question = $this->html_to_text($this->questiontext, $this->questiontextformat);

        $stems = array();

        foreach ($this->stemorder as $stemid) {

            $stems[] = $this->html_to_text($this->stems[$stemid], $this->stemformat[$stemid]);

        }

        $choices = array();

        foreach ($this->choiceorder as $choiceid) {

            $choices[] = $this->choices[$choiceid];

        }

        return $question . ' {' . implode('; ', $stems) . '} -> {' .

                implode('; ', $choices) . '}';

    }

    public function summarise_response(array $response) {

        $matches = array();

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

            if (array_key_exists($this->field($key), $response) && $response[$this->field($key)]) {

                $matches[] = $this->html_to_text($this->stems[$stemid],

                        $this->stemformat[$stemid]) . ' -> ' .

                        $this->choices[$this->choiceorder[$response[$this->field($key)]]];

            }

        }

        if (empty($matches)) {

            return null;

        }

        return implode('; ', $matches);

    }

    public function classify_response(array $response) {

        $selectedchoicekeys = array();

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

            if (array_key_exists($this->field($key), $response) && $response[$this->field($key)]) {

                $selectedchoicekeys[$stemid] = $this->choiceorder[$response[$this->field($key)]];

            } else {

                $selectedchoicekeys[$stemid] = 0;

            }

        }

        $parts = array();

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

            if ($this->right[$stemid] == 0 || !isset($selectedchoicekeys[$stemid])) {

                // Choice for a deleted subquestion, ignore. (See apply_attempt_state.)

                continue;

            }

            $selectedchoicekey = $selectedchoicekeys[$stemid];

            if (empty($selectedchoicekey)) {

                $parts[$stemid] = question_classified_response::no_response();

                continue;

            }

            $choice = $this->choices[$selectedchoicekey];

            if ($choice == get_string('deletedchoice', 'qtype_match')) {

                // Deleted choice, ignore. (See apply_attempt_state.)

                continue;

            }

            $parts[$stemid] = new question_classified_response(

                    $selectedchoicekey, $choice,

                    ($selectedchoicekey == $this->right[$stemid]) / count($this->stems));

        }

        return $parts;

    }

    public function clear_wrong_from_response(array $response) {

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

            if (!array_key_exists($this->field($key), $response) ||

                    $response[$this->field($key)] != $this->get_right_choice_for($stemid)) {

                $response[$this->field($key)] = 0;

            }

        }

        return $response;

    }

    public function get_num_parts_right(array $response) {

        $numright = 0;

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

            $fieldname = $this->field($key);

            if (!array_key_exists($fieldname, $response)) {

                continue;

            }

            $choice = $response[$fieldname];

            if ($choice && $this->choiceorder[$choice] == $this->right[$stemid]) {

                $numright += 1;

            }

        }

        return array($numright, count($this->stemorder));

    }

    /**

     * @param int $key stem number

     * @return string the question-type variable name.

     */

    protected function field($key) {

        return 'sub' . $key;

    }

    public function get_expected_data() {

        $vars = array();

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

            $vars[$this->field($key)] = PARAM_INT;

        }

        return $vars;

    }

    public function get_correct_response() {

        $response = array();

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

            $response[$this->field($key)] = $this->get_right_choice_for($stemid);

        }

        return $response;

    }

    public function prepare_simulated_post_data($simulatedresponse) {

        $postdata = array();

        $stemtostemids = array_flip(clean_param_array($this->stems, PARAM_NOTAGS));

        $choicetochoiceno = array_flip($this->choices);

        $choicenotochoiceselectvalue = array_flip($this->choiceorder);

        foreach ($simulatedresponse as $stem => $choice) {

            $choice = clean_param($choice, PARAM_NOTAGS);

            $stemid = $stemtostemids[$stem];

            $shuffledstemno = array_search($stemid, $this->stemorder);

            if (empty($choice)) {

                $choiceselectvalue = 0;

            } else if ($choicetochoiceno[$choice]) {

                $choiceselectvalue = $choicenotochoiceselectvalue[$choicetochoiceno[$choice]];

            } else {

                throw new coding_exception("Unknown choice {$choice} in matching question - {$this->name}.");

            }

            $postdata[$this->field($shuffledstemno)] = $choiceselectvalue;

        }

        return $postdata;

    }

    public function get_student_response_values_for_simulation($postdata) {

        $simulatedresponse = array();

        foreach ($this->stemorder as $shuffledstemno => $stemid) {

            if (!empty($postdata[$this->field($shuffledstemno)])) {

                $choiceselectvalue = $postdata[$this->field($shuffledstemno)];

                $choiceno = $this->choiceorder[$choiceselectvalue];

                $choice = clean_param($this->choices[$choiceno], PARAM_NOTAGS);

                $stem = clean_param($this->stems[$stemid], PARAM_NOTAGS);

                $simulatedresponse[$stem] = $choice;

            }

        }

        ksort($simulatedresponse);

        return $simulatedresponse;

    }

    public function get_right_choice_for($stemid) {

        foreach ($this->choiceorder as $choicekey => $choiceid) {

            if ($this->right[$stemid] == $choiceid) {

                return $choicekey;

            }

        }

    }

    public function is_complete_response(array $response) {

        $complete = true;

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

            $complete = $complete && !empty($response[$this->field($key)]);

        }

        return $complete;

    }

    public function is_gradable_response(array $response) {

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

            if (!empty($response[$this->field($key)])) {

                return true;

            }

        }

        return false;

    }

    public function get_validation_error(array $response) {

        if ($this->is_complete_response($response)) {

            return '';

        }

        return get_string('pleaseananswerallparts', 'qtype_match');

    }

    public function is_same_response(array $prevresponse, array $newresponse) {

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

            $fieldname = $this->field($key);

            if (!question_utils::arrays_same_at_key_integer(

                    $prevresponse, $newresponse, $fieldname)) {

                return false;

            }

        }

        return true;

    }

    public function grade_response(array $response) {

        list($right, $total) = $this->get_num_parts_right($response);

        $fraction = $right / $total;

        return array($fraction, question_state::graded_state_for_fraction($fraction));

    }

    public function compute_final_grade($responses, $totaltries) {

        $totalstemscore = 0;

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

            $fieldname = $this->field($key);

            $lastwrongindex = -1;

            $finallyright = false;

            foreach ($responses as $i => $response) {

                if (!array_key_exists($fieldname, $response) || !$response[$fieldname] ||

                        $this->choiceorder[$response[$fieldname]] != $this->right[$stemid]) {

                    $lastwrongindex = $i;

                    $finallyright = false;

                } else {

                    $finallyright = true;

                }

            }

            if ($finallyright) {

                $totalstemscore += max(0, 1 - ($lastwrongindex + 1) * $this->penalty);

            }

        }

        return $totalstemscore / count($this->stemorder);

    }

    public function get_stem_order() {

        return $this->stemorder;

    }

    public function get_choice_order() {

        return $this->choiceorder;

    }

    public function check_file_access($qa, $options, $component, $filearea, $args, $forcedownload) {

        if ($component == 'qtype_match' && $filearea == 'subquestion') {

            $subqid = reset($args); // Itemid is sub question id.

            return array_key_exists($subqid, $this->stems);

        } else if ($component == 'question' && in_array($filearea,

                array('correctfeedback', 'partiallycorrectfeedback', 'incorrectfeedback'))) {

            return $this->check_combined_feedback_file_access($qa, $options, $filearea, $args);

        } else if ($component == 'question' && $filearea == 'hint') {

            return $this->check_hint_file_access($qa, $options, $args);

        } else {

            return parent::check_file_access($qa, $options, $component, $filearea,

                    $args, $forcedownload);

        }

    }

    /**

     * Return the question settings that define this question as structured data.

     *

     * @param question_attempt $qa the current attempt for which we are exporting the settings.

     * @param question_display_options $options the question display options which say which aspects of the question

     * should be visible.

     * @return mixed structure representing the question settings. In web services, this will be JSON-encoded.

     */

    public function get_question_definition_for_external_rendering(question_attempt $qa, question_display_options $options) {

        // This is a partial implementation, returning only the most relevant question settings for now,

        // ideally, we should return as much as settings as possible (depending on the state and display options).

        return [

            'shufflestems' => $this->shufflestems,

        ];

    }

}