question/preview.php

   1 <?php // $Id$
   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     $quizid = optional_param('quizid', 0, PARAM_INT);
  25     // if no quiz id is specified then tell us the course
  26     if (empty($quizid)) {
  27         $courseid = required_param('courseid', PARAM_INT);
  28     }
  29
  30     // Test if we are continuing an attempt at a question
  31     $continue = optional_param('continue', 0, PARAM_BOOL);
  32     // Check for any of the submit buttons
  33     $fillcorrect = optional_param('fillcorrect', 0, PARAM_BOOL);
  34     $markall = optional_param('markall', 0, PARAM_BOOL);
  35     $finishattempt = optional_param('finishattempt', 0, PARAM_BOOL);
  36     $back = optional_param('back', 0, PARAM_BOOL);
  37     $startagain = optional_param('startagain', 0, PARAM_BOOL);
  38     // We are always continuing an attempt if a submit button was pressed with the
  39     // exception of the start again button
  40     if ($fillcorrect || $markall || $finishattempt || $back) {
  41         $continue = true;
  42     } else if ($startagain) {
  43         $continue = false;
  44     }
  45
  46
  47
  48     if (!$continue) {
  49         // Start a new attempt; delete the old session
  50         unset($SESSION->quizpreview);
  51         // Redirect to ourselves but with continue=1; prevents refreshing the page
  52         // from restarting an attempt (needed so that random questions don't change)
  53         $url = $CFG->wwwroot . '/question/preview.php?id=' . $id;
  54         if ($quizid) {
  55             $url .= '&amp;quizid=' . $quizid;
  56         } else {
  57             $url .= '&amp;courseid=' . $courseid;
  58         }
  59         $url .= '&amp;continue=1';
  60         redirect($url);
  61     }
  62     // Load the question information
  63     if (!$questions = get_records('question', 'id', $id)) {
  64         error('Could not load question');
  65     }
  66     if (empty($quizid)) {
  67         $quiz = new cmoptions;
  68         $quiz->id = 0;
  69         $quiz->review = $CFG->quiz_review;
  70         require_login($courseid, false);
  71         $quiz->course = $courseid;
  72     } else if (!$quiz = get_record('quiz', 'id', $quizid)) {
  73         error("Quiz id $quizid does not exist");
  74     } else {
  75         require_login($quiz->course, false, get_coursemodule_from_instance('quiz', $quizid, $quiz->course));
  76     }
  77
  78
  79
  80     if ($maxgrade = get_field('quiz_question_instances', 'grade', 'quiz', $quiz->id, 'question', $id)) {
  81         $questions[$id]->maxgrade = $maxgrade;
  82     } else {
  83         $questions[$id]->maxgrade = $questions[$id]->defaultgrade;
  84     }
  85
  86     $quiz->id = 0; // just for safety
  87     $quiz->questions = $id;
  88
  89     if (!$category = get_record("question_categories", "id", $questions[$id]->category)) {
  90         error("This question doesn't belong to a valid category!");
  91     }
  92
  93     if (!question_has_capability_on($questions[$id], 'use', $questions[$id]->category)){
  94         error("You can't preview these questions!");
  95     }
  96     if (isset($COURSE)){
  97         $quiz->course = $COURSE->id;
  98     }
  99
 100     // Load the question type specific information
 101     if (!get_question_options($questions)) {
 102         error(get_string('newattemptfail', 'quiz'));
 103     }
 104
 105     // Create a dummy quiz attempt
 106     // TODO: find out what of the following we really need. What is $attempt
 107     //       really used for?
 108     $timenow = time();
 109     $attempt->quiz = $quiz->id;
 110     $attempt->userid = $USER->id;
 111     $attempt->attempt = 0;
 112     $attempt->sumgrades = 0;
 113     $attempt->timestart = $timenow;
 114     $attempt->timefinish = 0;
 115     $attempt->timemodified = $timenow;
 116     $attempt->uniqueid = 0;
 117     $attempt->id = 0;
 118
 119     // Restore the history of question sessions from the moodle session or create
 120     // new sessions. Make $states a reference to the states array in the moodle
 121     // session.
 122     if (isset($SESSION->quizpreview->states) and $SESSION->quizpreview->questionid
 123      == $id) {
 124         // Reload the question session history from the moodle session
 125         $states =& $SESSION->quizpreview->states;
 126         $historylength = count($states) - 1;
 127         if ($back && $historylength > 0) {
 128             // Go back one step in the history
 129             unset($states[$historylength]);
 130             $historylength--;
 131         }
 132     } else {
 133         // Record the question id in the moodle session
 134         $SESSION->quizpreview->questionid = $id;
 135         // Create an empty session for the question
 136         if (!$newstates =
 137          get_question_states($questions, $quiz, $attempt)) {
 138             error(get_string('newattemptfail', 'quiz'));
 139         }
 140         $SESSION->quizpreview->states = array($newstates);
 141         $states =& $SESSION->quizpreview->states;
 142         $historylength = 0;
 143     }
 144
 145     if (!$fillcorrect && !$back && ($form = data_submitted())) {
 146         $form = (array)$form;
 147         $submitted = true;
 148
 149         // Create a new item in the history of question states (don't simplify!)
 150         $states[$historylength + 1] = array();
 151         $states[$historylength + 1][$id] = clone($states[$historylength][$id]);
 152         $historylength++;
 153         $curstate =& $states[$historylength][$id];
 154         $curstate->changed = false;
 155
 156         // Process the responses
 157         unset($form['id']);
 158         unset($form['quizid']);
 159         unset($form['continue']);
 160         unset($form['markall']);
 161         unset($form['finishattempt']);
 162         unset($form['back']);
 163         unset($form['startagain']);
 164
 165         $event = $finishattempt ? QUESTION_EVENTCLOSE : QUESTION_EVENTSUBMIT;
 166         if ($actions = question_extract_responses($questions, $form, $event)) {
 167             $actions[$id]->timestamp = 0; // We do not care about timelimits here
 168             question_process_responses($questions[$id], $curstate, $actions[$id], $quiz, $attempt);
 169             if (!$curstate->changed) {
 170                 // Update the current state rather than creating a new one
 171                 $historylength--;
 172                 unset($states[$historylength]);
 173                 $states = array_values($states);
 174                 $curstate =& $states[$historylength][$id];
 175             }
 176         }
 177     } else {
 178         $submitted = false;
 179         $curstate =& $states[$historylength][$id];
 180     }
 181
 182     // TODO: should not use quiz-specific function here
 183     $options = quiz_get_renderoptions($quiz->review, $curstate);
 184
 185     // Fill in the correct responses (unless the question is in readonly mode)
 186     if ($fillcorrect && !$options->readonly) {
 187         $curstate->responses = $QTYPES[$questions[$id]->qtype]
 188          ->get_correct_responses($questions[$id], $curstate);
 189     }
 190
 191     $strpreview = get_string('preview', 'quiz').' '.format_string($questions[$id]->name);
 192     $questionlist = array($id);
 193     $headtags = get_html_head_contributions($questionlist, $questions, $states[$historylength]);
 194     print_header($strpreview, '', '', '', $headtags);
 195     print_heading($strpreview);
 196
 197     if (!empty($quizid)) {
 198         echo '<p class="quemodname">'.get_string('modulename', 'quiz') . ': ';
 199         p($quiz->name);
 200         echo "</p>\n";
 201     }
 202     $number = 1;
 203     echo '<form method="post" action="preview.php" enctype="multipart/form-data" id="responseform">', "\n";
 204     print_question($questions[$id], $curstate, $number, $quiz, $options);
 205     echo '<br />';
 206
 207
 208
 209     echo '<div class="controls">';
 210     echo "<input type=\"hidden\" name=\"id\" value=\"$id\" />\n";
 211     echo "<input type=\"hidden\" name=\"quizid\" value=\"$quizid\" />\n";
 212     echo "<input type=\"hidden\" name=\"courseid\" value=\"$courseid\" />\n";
 213     echo "<input type=\"hidden\" name=\"continue\" value=\"1\" />\n";
 214
 215     // Print the mark and finish attempt buttons
 216     echo '<input name="markall" type="submit" value="' . get_string('markall',
 217      'quiz') . "\" />\n";
 218     echo '<input name="finishattempt" type="submit" value="' .
 219      get_string('finishattempt', 'quiz') . "\" />\n";
 220     echo '<br />';
 221     echo '<br />';
 222     // Print the fill correct button (unless the question is in readonly mode)
 223     if (!$options->readonly) {
 224         echo '<input name="fillcorrect" type="submit" value="' .
 225          get_string('fillcorrect', 'quiz') . "\" />\n";
 226     }
 227     // Print the navigation buttons
 228     if ($historylength > 0) {
 229         echo '<input name="back" type="submit" value="' . get_string('previous',
 230          'quiz') . "\" />\n";
 231     }
 232     // Print the start again button
 233     echo '<input name="startagain" type="submit" value="' .
 234      get_string('startagain', 'quiz') . "\" />\n";
 235     // Print the close window button
 236     echo '<input type="button" onclick="window.close()" value="' .
 237      get_string('closepreview', 'quiz') . "\" />";
 238     echo '</div>';
 239     echo '</form>';
 240     print_footer();
 241 ?>