question/preview.php

   1 <?php
   2 /**
   3  * This page displays a preview of a question
   4  *
   5  * The preview uses the option settings from the activity within which the question
   6  * is previewed or the default settings if no activity is specified. The question session
   7  * information is stored in the session as an array of subsequent states rather
   8  * than in the database.
   9  *
  10  * TODO: make this work with activities other than quiz
  11  *
  12  * @author Alex Smith as part of the Serving Mathematics project
  13  *         {@link http://maths.york.ac.uk/serving_maths}
  14  * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
  15  * @package questionbank
  16  */
  17
  18     require_once("../config.php");
  19     require_once($CFG->libdir.'/questionlib.php');
  20     require_once($CFG->dirroot.'/mod/quiz/locallib.php'); // We really want to get rid of this
  21
  22     $id = required_param('id', PARAM_INT);        // question id
  23     // if no quiz id is specified then a dummy quiz with default options is used
  24     $quizid = optional_param('quizid', 0, PARAM_INT);
  25     // if no quiz id is specified then tell us the course
  26
  27     $pageurl = new moodle_url('/question/preview.php', array('id' => $id, 'continue' => 1));
  28     if (empty($quizid)) {
  29         $courseid = required_param('courseid', PARAM_INT);
  30         $pageurl->param('courseid', $courseid);
  31     } else {
  32         $pageurl->param('quizid', $quizid);
  33     }
  34     $PAGE->set_url($pageurl);
  35     $PAGE->set_pagelayout('popup');
  36
  37     // Test if we are continuing an attempt at a question
  38     $continue = optional_param('continue', 0, PARAM_BOOL);
  39     // Check for any of the submit buttons
  40     $fillcorrect = optional_param('fillcorrect', 0, PARAM_BOOL);
  41     $markall = optional_param('markall', 0, PARAM_BOOL);
  42     $finishattempt = optional_param('finishattempt', 0, PARAM_BOOL);
  43     $back = optional_param('back', 0, PARAM_BOOL);
  44     $startagain = optional_param('startagain', 0, PARAM_BOOL);
  45     // We are always continuing an attempt if a submit button was pressed with the
  46     // exception of the start again button
  47     if ($fillcorrect || $markall || $finishattempt || $back) {
  48         $continue = true;
  49     } else if ($startagain) {
  50         $continue = false;
  51     }
  52
  53     $url = new moodle_url('/question/preview.php');
  54     $url->param('id', $id);
  55     if ($quizid) {
  56         $url->param('quizid', $quizid);
  57     } else {
  58         $url->param('courseid', $courseid);
  59     }
  60     $url->param('continue', 1);
  61     if (!$continue) {
  62         // Start a new attempt; delete the old session
  63         unset($SESSION->quizpreview);
  64         // Redirect to ourselves but with continue=1; prevents refreshing the page
  65         // from restarting an attempt (needed so that random questions don't change)
  66         redirect($url);
  67     }
  68     // Load the question information
  69     if (!$questions = $DB->get_records('question', array('id' =>  $id))) {
  70         print_error('cannotloadquestion', 'question');
  71     }
  72     if (empty($quizid)) {
  73         $quiz = new cmoptions;
  74         $quiz->id = 0;
  75         $quiz->review = get_config('quiz', 'review');
  76         require_login($courseid, false);
  77         $quiz->course = $courseid;
  78         $quiz->decimalpoints = get_config('quiz', 'decimalpoints');
  79         $context = get_context_instance(CONTEXT_COURSE, $courseid);
  80     } else if (!$quiz = $DB->get_record('quiz', array('id' => $quizid))) {
  81         print_error('invalidquizid', 'quiz', '', $quizid);
  82     } else {
  83         $cm = get_coursemodule_from_instance('quiz', $quizid, $quiz->course);
  84         require_login($quiz->course, false, $cm);
  85         $context = get_context_instance(CONTEXT_MODULE, $cm->id);
  86     }
  87
  88     if ($maxgrade = $DB->get_field('quiz_question_instances', 'grade', array('quiz' => $quiz->id, 'question' => $id))) {
  89         $questions[$id]->maxgrade = $maxgrade;
  90     } else {
  91         $questions[$id]->maxgrade = $questions[$id]->defaultgrade;
  92     }
  93
  94     $quiz->id = 0; // just for safety
  95     $quiz->questions = $id;
  96
  97     if (!$category = $DB->get_record("question_categories", array("id" => $questions[$id]->category))) {
  98         print_error('invalidquestionid', 'quiz');
  99     }
 100
 101     if (!question_has_capability_on($questions[$id], 'use', $questions[$id]->category)){
 102         print_error('cannotpreview', 'question');
 103     }
 104     if (isset($COURSE)){
 105         $quiz->course = $COURSE->id;
 106     }
 107
 108     // Load the question type specific information
 109     if (!get_question_options($questions)) {
 110         print_error('newattemptfail', 'quiz');
 111     }
 112
 113     // Create a dummy quiz attempt
 114     // TODO: find out what of the following we really need. What is $attempt
 115     //       really used for?
 116     $timenow = time();
 117     $attempt->quiz = $quiz->id;
 118     $attempt->userid = $USER->id;
 119     $attempt->attempt = 0;
 120     $attempt->sumgrades = 0;
 121     $attempt->timestart = $timenow;
 122     $attempt->timefinish = 0;
 123     $attempt->timemodified = $timenow;
 124     $attempt->uniqueid = 0;
 125     $attempt->id = 0;
 126     $attempt->layout = $id;
 127
 128     // Restore the history of question sessions from the moodle session or create
 129     // new sessions. Make $states a reference to the states array in the moodle
 130     // session.
 131     if (isset($SESSION->quizpreview->states) and $SESSION->quizpreview->questionid == $id) {
 132         // Reload the question session history from the moodle session
 133         $states =& $SESSION->quizpreview->states;
 134         $historylength = count($states) - 1;
 135         if ($back && $historylength > 0) {
 136             // Go back one step in the history
 137             unset($states[$historylength]);
 138             $historylength--;
 139         }
 140     } else {
 141         // Record the question id in the moodle session
 142         $SESSION->quizpreview->questionid = $id;
 143         // Create an empty session for the question
 144         if (!$newstates = get_question_states($questions, $quiz, $attempt)) {
 145             print_error('newattemptfail', 'quiz');
 146         }
 147         $newstates[$id]->questionsessionid = 0;
 148         $SESSION->quizpreview->states = array($newstates);
 149         $states =& $SESSION->quizpreview->states;
 150         $historylength = 0;
 151     }
 152
 153     if (!$fillcorrect && !$back && ($form = data_submitted())) {
 154         $form = (array)$form;
 155         $submitted = true;
 156
 157         // Create a new item in the history of question states (don't simplify!)
 158         $states[$historylength + 1] = array();
 159         $states[$historylength + 1][$id] = clone($states[$historylength][$id]);
 160         $historylength++;
 161         $curstate =& $states[$historylength][$id];
 162         $curstate->changed = false;
 163
 164         // Process the responses
 165         unset($form['id']);
 166         unset($form['quizid']);
 167         unset($form['continue']);
 168         unset($form['markall']);
 169         unset($form['finishattempt']);
 170         unset($form['back']);
 171         unset($form['startagain']);
 172
 173         if ($finishattempt) {
 174             $event = QUESTION_EVENTCLOSE;
 175         } else if ($markall) {
 176             $event = QUESTION_EVENTSUBMIT;
 177         } else {
 178             $event = QUESTION_EVENTSAVE;
 179         }
 180         if ($actions = question_extract_responses($questions, $form, $event)) {
 181             $actions[$id]->timestamp = 0; // We do not care about timelimits here
 182             if (!question_process_responses($questions[$id], $curstate, $actions[$id], $quiz, $attempt)) {
 183                 unset($SESSION->quizpreview);
 184                 print_error('errorprocessingresponses', 'question', $url->out());
 185             }
 186             if (!$curstate->changed) {
 187                 // Update the current state rather than creating a new one
 188                 $historylength--;
 189                 unset($states[$historylength]);
 190                 $states = array_values($states);
 191                 $curstate =& $states[$historylength][$id];
 192             }
 193         }
 194     } else {
 195         $submitted = false;
 196         $curstate =& $states[$historylength][$id];
 197     }
 198
 199     // TODO: should not use quiz-specific function here
 200     $options = quiz_get_renderoptions($quiz, $attempt, $context, $curstate);
 201     $options->noeditlink = true;
 202
 203     // Fill in the correct responses (unless the question is in readonly mode)
 204     if ($fillcorrect && !$options->readonly) {
 205         $curstate->responses = $QTYPES[$questions[$id]->qtype]->get_correct_responses($questions[$id], $curstate);
 206     }
 207
 208     $strpreview = get_string('preview', 'quiz').' '.format_string($questions[$id]->name);
 209     $questionlist = array($id);
 210     question_get_html_head_contributions($questionlist, $questions, $states[$historylength]);
 211     $PAGE->set_title($strpreview);
 212     $PAGE->set_heading($COURSE->fullname);
 213     echo $OUTPUT->header();
 214
 215     if (!empty($quizid)) {
 216         echo '<p class="quemodname">'.get_string('modulename', 'quiz') . ': ';
 217         p(format_string($quiz->name));
 218         echo "</p>\n";
 219     }
 220     $number = 1;
 221     echo '<form method="post" action="'.$url->out_omit_querystring().'" enctype="multipart/form-data" id="responseform">', "\n";
 222     $PAGE->requires->js_init_call('M.core_question_engine.init_form', array('#responseform'));
 223
 224     print_question($questions[$id], $curstate, $number, $quiz, $options, $context);
 225
 226     echo '<div class="controls">';
 227     echo html_writer::input_hidden_params($url);
 228
 229     // Print the mark and finish attempt buttons
 230     echo '<input name="markall" type="submit" value="' . get_string('markall',
 231      'quiz') . "\" />\n";
 232     echo '<input name="finishattempt" type="submit" value="' .
 233      get_string('submitallandfinish', 'quiz') . "\" />\n";
 234     echo '<br />';
 235     echo '<br />';
 236     // Print the fill correct button (unless the question is in readonly mode)
 237     if (!$options->readonly) {
 238         echo '<input name="fillcorrect" type="submit" value="' .
 239          get_string('fillcorrect', 'quiz') . "\" />\n";
 240     }
 241     // Print the navigation buttons
 242     if ($historylength > 0) {
 243         echo '<input name="back" type="submit" value="' . get_string('previous',
 244          'quiz') . "\" />\n";
 245     }
 246     // Print the start again button
 247     echo '<input name="startagain" type="submit" value="' .
 248      get_string('startagain', 'quiz') . "\" />\n";
 249     // Print the close window button
 250     echo '<input type="button" onclick="window.close()" value="' .
 251      get_string('closepreview', 'quiz') . "\" />";
 252     echo '</div>';
 253     echo '</form>';
 254     echo $OUTPUT->footer();
 255