question/preview.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * This page displays a preview of a question
  19  *
  20  * The preview uses the option settings from the activity within which the question
  21  * is previewed or the default settings if no activity is specified. The question session
  22  * information is stored in the session as an array of subsequent states rather
  23  * than in the database.
  24  *
  25  * @package    moodlecore
  26  * @subpackage questionengine
  27  * @copyright  Alex Smith {@link http://maths.york.ac.uk/serving_maths} and
  28  *      numerous contributors.
  29  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  30  */
  31
  32
  33 require_once(__DIR__ . '/../config.php');
  34 require_once($CFG->libdir . '/questionlib.php');
  35 require_once(__DIR__ . '/previewlib.php');
  36
  37 /**
  38  * The maximum number of variants previewable. If there are more variants than this for a question
  39  * then we only allow the selection of the first x variants.
  40  * @var integer
  41  */
  42 define('QUESTION_PREVIEW_MAX_VARIANTS', 100);
  43
  44 // Get and validate question id.
  45 $id = required_param('id', PARAM_INT);
  46 $question = question_bank::load_question($id);
  47
  48 // Were we given a particular context to run the question in?
  49 // This affects things like filter settings, or forced theme or language.
  50 if ($cmid = optional_param('cmid', 0, PARAM_INT)) {
  51     $cm = get_coursemodule_from_id(false, $cmid);
  52     require_login($cm->course, false, $cm);
  53     $context = context_module::instance($cmid);
  54
  55 } else if ($courseid = optional_param('courseid', 0, PARAM_INT)) {
  56     require_login($courseid);
  57     $context = context_course::instance($courseid);
  58
  59 } else {
  60     require_login();
  61     $category = $DB->get_record('question_categories',
  62             array('id' => $question->category), '*', MUST_EXIST);
  63     $context = context::instance_by_id($category->contextid);
  64     $PAGE->set_context($context);
  65     // Note that in the other cases, require_login will set the correct page context.
  66 }
  67 question_require_capability_on($question, 'use');
  68 $PAGE->set_pagelayout('popup');
  69
  70 // Get and validate display options.
  71 $maxvariant = min($question->get_num_variants(), QUESTION_PREVIEW_MAX_VARIANTS);
  72 $options = new question_preview_options($question);
  73 $options->load_user_defaults();
  74 $options->set_from_request();
  75 $PAGE->set_url(question_preview_url($id, $options->behaviour, $options->maxmark,
  76         $options, $options->variant, $context));
  77
  78 // Get and validate existing preview, or start a new one.
  79 $previewid = optional_param('previewid', 0, PARAM_INT);
  80
  81 if ($previewid) {
  82     try {
  83         $quba = question_engine::load_questions_usage_by_activity($previewid);
  84
  85     } catch (Exception $e) {
  86         // This may not seem like the right error message to display, but
  87         // actually from the user point of view, it makes sense.
  88         print_error('submissionoutofsequencefriendlymessage', 'question',
  89                 question_preview_url($question->id, $options->behaviour,
  90                 $options->maxmark, $options, $options->variant, $context), null, $e);
  91     }
  92
  93     if ($quba->get_owning_context()->instanceid != $USER->id) {
  94         print_error('notyourpreview', 'question');
  95     }
  96
  97     $slot = $quba->get_first_question_number();
  98     $usedquestion = $quba->get_question($slot, false);
  99     if ($usedquestion->id != $question->id) {
 100         print_error('questionidmismatch', 'question');
 101     }
 102     $question = $usedquestion;
 103     $options->variant = $quba->get_variant($slot);
 104
 105 } else {
 106     $quba = question_engine::make_questions_usage_by_activity(
 107             'core_question_preview', context_user::instance($USER->id));
 108     $quba->set_preferred_behaviour($options->behaviour);
 109     $slot = $quba->add_question($question, $options->maxmark);
 110
 111     if ($options->variant) {
 112         $options->variant = min($maxvariant, max(1, $options->variant));
 113     } else {
 114         $options->variant = rand(1, $maxvariant);
 115     }
 116
 117     $quba->start_question($slot, $options->variant);
 118
 119     $transaction = $DB->start_delegated_transaction();
 120     question_engine::save_questions_usage_by_activity($quba);
 121     $transaction->allow_commit();
 122 }
 123 $options->behaviour = $quba->get_preferred_behaviour();
 124 $options->maxmark = $quba->get_question_max_mark($slot);
 125
 126 // Create the settings form, and initialise the fields.
 127 $optionsform = new preview_options_form(question_preview_form_url($question->id, $context, $previewid),
 128         array('quba' => $quba, 'maxvariant' => $maxvariant));
 129 $optionsform->set_data($options);
 130
 131 // Process change of settings, if that was requested.
 132 if ($newoptions = $optionsform->get_submitted_data()) {
 133     // Set user preferences.
 134     $options->save_user_preview_options($newoptions);
 135     if (!isset($newoptions->variant)) {
 136         $newoptions->variant = $options->variant;
 137     }
 138     if (isset($newoptions->saverestart)) {
 139         restart_preview($previewid, $question->id, $newoptions, $context);
 140     }
 141 }
 142
 143 // Prepare a URL that is used in various places.
 144 $actionurl = question_preview_action_url($question->id, $quba->get_id(), $options, $context);
 145
 146 // Process any actions from the buttons at the bottom of the form.
 147 if (data_submitted() && confirm_sesskey()) {
 148
 149     try {
 150
 151         if (optional_param('restart', false, PARAM_BOOL)) {
 152             restart_preview($previewid, $question->id, $options, $context);
 153
 154         } else if (optional_param('fill', null, PARAM_BOOL)) {
 155             $correctresponse = $quba->get_correct_response($slot);
 156             if (!is_null($correctresponse)) {
 157                 $quba->process_action($slot, $correctresponse);
 158
 159                 $transaction = $DB->start_delegated_transaction();
 160                 question_engine::save_questions_usage_by_activity($quba);
 161                 $transaction->allow_commit();
 162             }
 163             redirect($actionurl);
 164
 165         } else if (optional_param('finish', null, PARAM_BOOL)) {
 166             $quba->process_all_actions();
 167             $quba->finish_all_questions();
 168
 169             $transaction = $DB->start_delegated_transaction();
 170             question_engine::save_questions_usage_by_activity($quba);
 171             $transaction->allow_commit();
 172             redirect($actionurl);
 173
 174         } else {
 175             $quba->process_all_actions();
 176
 177             $transaction = $DB->start_delegated_transaction();
 178             question_engine::save_questions_usage_by_activity($quba);
 179             $transaction->allow_commit();
 180
 181             $scrollpos = optional_param('scrollpos', '', PARAM_RAW);
 182             if ($scrollpos !== '') {
 183                 $actionurl->param('scrollpos', (int) $scrollpos);
 184             }
 185             redirect($actionurl);
 186         }
 187
 188     } catch (question_out_of_sequence_exception $e) {
 189         print_error('submissionoutofsequencefriendlymessage', 'question', $actionurl);
 190
 191     } catch (Exception $e) {
 192         // This sucks, if we display our own custom error message, there is no way
 193         // to display the original stack trace.
 194         $debuginfo = '';
 195         if (!empty($e->debuginfo)) {
 196             $debuginfo = $e->debuginfo;
 197         }
 198         print_error('errorprocessingresponses', 'question', $actionurl,
 199                 $e->getMessage(), $debuginfo);
 200     }
 201 }
 202
 203 if ($question->length) {
 204     $displaynumber = '1';
 205 } else {
 206     $displaynumber = 'i';
 207 }
 208 $restartdisabled = array();
 209 $finishdisabled = array();
 210 $filldisabled = array();
 211 if ($quba->get_question_state($slot)->is_finished()) {
 212     $finishdisabled = array('disabled' => 'disabled');
 213     $filldisabled = array('disabled' => 'disabled');
 214 }
 215 // If question type cannot give us a correct response, disable this button.
 216 if (is_null($quba->get_correct_response($slot))) {
 217     $filldisabled = array('disabled' => 'disabled');
 218 }
 219 if (!$previewid) {
 220     $restartdisabled = array('disabled' => 'disabled');
 221 }
 222
 223 // Prepare technical info to be output.
 224 $qa = $quba->get_question_attempt($slot);
 225 $technical = array();
 226 $technical[] = get_string('behaviourbeingused', 'question',
 227         question_engine::get_behaviour_name($qa->get_behaviour_name()));
 228 $technical[] = get_string('technicalinfominfraction',     'question', $qa->get_min_fraction());
 229 $technical[] = get_string('technicalinfomaxfraction',     'question', $qa->get_max_fraction());
 230 $technical[] = get_string('technicalinfovariant',         'question', $qa->get_variant());
 231 $technical[] = get_string('technicalinfoquestionsummary', 'question', s($qa->get_question_summary()));
 232 $technical[] = get_string('technicalinforightsummary',    'question', s($qa->get_right_answer_summary()));
 233 $technical[] = get_string('technicalinforesponsesummary', 'question', s($qa->get_response_summary()));
 234 $technical[] = get_string('technicalinfostate',           'question', '' . $qa->get_state());
 235
 236 // Start output.
 237 $title = get_string('previewquestion', 'question', format_string($question->name));
 238 $headtags = question_engine::initialise_js() . $quba->render_question_head_html($slot);
 239 $PAGE->set_title($title);
 240 $PAGE->set_heading($title);
 241 echo $OUTPUT->header();
 242
 243 // Start the question form.
 244 echo html_writer::start_tag('form', array('method' => 'post', 'action' => $actionurl,
 245         'enctype' => 'multipart/form-data', 'id' => 'responseform'));
 246 echo html_writer::start_tag('div');
 247 echo html_writer::empty_tag('input', array('type' => 'hidden', 'name' => 'sesskey', 'value' => sesskey()));
 248 echo html_writer::empty_tag('input', array('type' => 'hidden', 'name' => 'slots', 'value' => $slot));
 249 echo html_writer::empty_tag('input', array('type' => 'hidden', 'name' => 'scrollpos', 'value' => '', 'id' => 'scrollpos'));
 250 echo html_writer::end_tag('div');
 251
 252 // Output the question.
 253 echo $quba->render_question($slot, $options, $displaynumber);
 254
 255 // Finish the question form.
 256 echo html_writer::start_tag('div', array('id' => 'previewcontrols', 'class' => 'controls'));
 257 echo html_writer::empty_tag('input', $restartdisabled + array('type' => 'submit',
 258         'name' => 'restart', 'value' => get_string('restart', 'question'), 'class' => 'btn btn-secondary'));
 259 echo html_writer::empty_tag('input', $finishdisabled  + array('type' => 'submit',
 260         'name' => 'save',    'value' => get_string('save', 'question'), 'class' => 'btn btn-secondary'));
 261 echo html_writer::empty_tag('input', $filldisabled    + array('type' => 'submit',
 262         'name' => 'fill',    'value' => get_string('fillincorrect', 'question'), 'class' => 'btn btn-secondary'));
 263 echo html_writer::empty_tag('input', $finishdisabled  + array('type' => 'submit',
 264         'name' => 'finish',  'value' => get_string('submitandfinish', 'question'), 'class' => 'btn btn-secondary'));
 265 echo html_writer::end_tag('div');
 266 echo html_writer::end_tag('form');
 267
 268 // Output the technical info.
 269 print_collapsible_region_start('', 'techinfo', get_string('technicalinfo', 'question'),
 270         'core_question_preview_techinfo_collapsed', true, false, $OUTPUT->help_icon('technicalinfo', 'question'));
 271 foreach ($technical as $info) {
 272     echo html_writer::tag('p', $info, array('class' => 'notifytiny'));
 273 }
 274 print_collapsible_region_end();
 275
 276 // Output a link to export this single question.
 277 if (question_has_capability_on($question, 'view')) {
 278     echo html_writer::link(question_get_export_single_question_url($question),
 279             get_string('exportonequestion', 'question'));
 280 }
 281
 282 // Log the preview of this question.
 283 $event = \core\event\question_viewed::create_from_question_instance($question, $context);
 284 $event->trigger();
 285
 286 // Display the settings form.
 287 $optionsform->display();
 288
 289 $PAGE->requires->js_module('core_question_engine');
 290 $PAGE->requires->strings_for_js(array(
 291     'closepreview',
 292 ), 'question');
 293 $PAGE->requires->yui_module('moodle-question-preview', 'M.question.preview.init');
 294 echo $OUTPUT->footer();
 295