mod/quiz/startattempt.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 script deals with starting a new attempt at a quiz.
  19  *
  20  * Normally, it will end up redirecting to attempt.php - unless a password form is displayed.
  21  *
  22  * This code used to be at the top of attempt.php, if you are looking for CVS history.
  23  *
  24  * @package   mod_quiz
  25  * @copyright 2009 The Open University
  26  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  27  */
  28
  29 require_once(dirname(__FILE__) . '/../../config.php');
  30 require_once($CFG->dirroot . '/mod/quiz/locallib.php');
  31
  32 // Get submitted parameters.
  33 $id = required_param('cmid', PARAM_INT); // Course module id
  34 $forcenew = optional_param('forcenew', false, PARAM_BOOL); // Used to force a new preview
  35 $page = optional_param('page', -1, PARAM_INT); // Page to jump to in the attempt.
  36
  37 if (!$cm = get_coursemodule_from_id('quiz', $id)) {
  38     print_error('invalidcoursemodule');
  39 }
  40 if (!$course = $DB->get_record('course', array('id' => $cm->course))) {
  41     print_error("coursemisconf");
  42 }
  43
  44 $quizobj = quiz::create($cm->instance, $USER->id);
  45 // This script should only ever be posted to, so set page URL to the view page.
  46 $PAGE->set_url($quizobj->view_url());
  47
  48 // Check login and sesskey.
  49 require_login($quizobj->get_course(), false, $quizobj->get_cm());
  50 require_sesskey();
  51
  52 // If no questions have been set up yet redirect to edit.php or display an error.
  53 if (!$quizobj->has_questions()) {
  54     if ($quizobj->has_capability('mod/quiz:manage')) {
  55         redirect($quizobj->edit_url());
  56     } else {
  57         print_error('cannotstartnoquestions', 'quiz', $quizobj->view_url());
  58     }
  59 }
  60
  61 // Create an object to manage all the other (non-roles) access rules.
  62 $timenow = time();
  63 $accessmanager = $quizobj->get_access_manager($timenow);
  64 if ($quizobj->is_preview_user() && $forcenew) {
  65     $accessmanager->current_attempt_finished();
  66 }
  67
  68 // Check capabilities.
  69 if (!$quizobj->is_preview_user()) {
  70     $quizobj->require_capability('mod/quiz:attempt');
  71 }
  72
  73 // Check to see if a new preview was requested.
  74 if ($quizobj->is_preview_user() && $forcenew) {
  75     // To force the creation of a new preview, we mark the current attempt (if any)
  76     // as finished. It will then automatically be deleted below.
  77     $DB->set_field('quiz_attempts', 'state', quiz_attempt::FINISHED,
  78             array('quiz' => $quizobj->get_quizid(), 'userid' => $USER->id));
  79 }
  80
  81 // Look for an existing attempt.
  82 $attempts = quiz_get_user_attempts($quizobj->get_quizid(), $USER->id, 'all', true);
  83 $lastattempt = end($attempts);
  84
  85 // If an in-progress attempt exists, check password then redirect to it.
  86 if ($lastattempt && ($lastattempt->state == quiz_attempt::IN_PROGRESS ||
  87         $lastattempt->state == quiz_attempt::OVERDUE)) {
  88     $currentattemptid = $lastattempt->id;
  89     $messages = $accessmanager->prevent_access();
  90
  91     // If the attempt is now overdue, deal with that.
  92     $quizobj->create_attempt_object($lastattempt)->handle_if_time_expired($timenow, true);
  93
  94     // And, if the attempt is now no longer in progress, redirect to the appropriate place.
  95     if ($lastattempt->state == quiz_attempt::OVERDUE) {
  96          redirect($quizobj->summary_url($lastattempt->id));
  97     } else if ($lastattempt->state != quiz_attempt::IN_PROGRESS) {
  98         redirect($quizobj->review_url($lastattempt->id));
  99     }
 100
 101     // If the page number was not explicitly in the URL, go to the current page.
 102     if ($page == -1) {
 103         $page = $lastattempt->currentpage;
 104     }
 105
 106 } else {
 107     // Get number for the next or unfinished attempt.
 108     if ($lastattempt && !$lastattempt->preview && !$quizobj->is_preview_user()) {
 109         $attemptnumber = $lastattempt->attempt + 1;
 110     } else {
 111         $lastattempt = false;
 112         $attemptnumber = 1;
 113     }
 114     $currentattemptid = null;
 115
 116     $messages = $accessmanager->prevent_access() +
 117             $accessmanager->prevent_new_attempt(count($attempts), $lastattempt);
 118
 119     if ($page == -1) {
 120         $page = 0;
 121     }
 122 }
 123
 124 // Check access.
 125 $output = $PAGE->get_renderer('mod_quiz');
 126 if (!$quizobj->is_preview_user() && $messages) {
 127     print_error('attempterror', 'quiz', $quizobj->view_url(),
 128             $output->access_messages($messages));
 129 }
 130
 131 if ($accessmanager->is_preflight_check_required($currentattemptid)) {
 132     // Need to do some checks before allowing the user to continue.
 133     $mform = $accessmanager->get_preflight_check_form(
 134             $quizobj->start_attempt_url($page), $currentattemptid);
 135
 136     if ($mform->is_cancelled()) {
 137         $accessmanager->back_to_view_page($output);
 138
 139     } else if (!$mform->get_data()) {
 140
 141         // Form not submitted successfully, re-display it and stop.
 142         $PAGE->set_url($quizobj->start_attempt_url($page));
 143         $PAGE->set_title(format_string($quizobj->get_quiz_name()));
 144         $accessmanager->setup_attempt_page($PAGE);
 145         if (empty($quizobj->get_quiz()->showblocks)) {
 146             $PAGE->blocks->show_only_fake_blocks();
 147         }
 148
 149         echo $output->start_attempt_page($quizobj, $mform);
 150         die();
 151     }
 152
 153     // Pre-flight check passed.
 154     $accessmanager->notify_preflight_check_passed($currentattemptid);
 155 }
 156 if ($currentattemptid) {
 157     redirect($quizobj->attempt_url($currentattemptid, $page));
 158 }
 159
 160 // Delete any previous preview attempts belonging to this user.
 161 quiz_delete_previews($quizobj->get_quiz(), $USER->id);
 162
 163 $quba = question_engine::make_questions_usage_by_activity('mod_quiz', $quizobj->get_context());
 164 $quba->set_preferred_behaviour($quizobj->get_quiz()->preferredbehaviour);
 165
 166 // Create the new attempt and initialize the question sessions
 167 $timenow = time(); // Update time now, in case the server is running really slowly.
 168 $attempt = quiz_create_attempt($quizobj, $attemptnumber, $lastattempt, $timenow,
 169         $quizobj->is_preview_user());
 170
 171 if (!($quizobj->get_quiz()->attemptonlast && $lastattempt)) {
 172     // Starting a normal, new, quiz attempt.
 173
 174     // Fully load all the questions in this quiz.
 175     $quizobj->preload_questions();
 176     $quizobj->load_questions();
 177
 178     // Add them all to the $quba.
 179     $idstoslots = array();
 180     $questionsinuse = array_keys($quizobj->get_questions());
 181     foreach ($quizobj->get_questions() as $i => $questiondata) {
 182         if ($questiondata->qtype != 'random') {
 183             if (!$quizobj->get_quiz()->shuffleanswers) {
 184                 $questiondata->options->shuffleanswers = false;
 185             }
 186             $question = question_bank::make_question($questiondata);
 187
 188         } else {
 189             $question = question_bank::get_qtype('random')->choose_other_question(
 190                     $questiondata, $questionsinuse, $quizobj->get_quiz()->shuffleanswers);
 191             if (is_null($question)) {
 192                 throw new moodle_exception('notenoughrandomquestions', 'quiz',
 193                         $quizobj->view_url(), $questiondata);
 194             }
 195         }
 196
 197         $idstoslots[$i] = $quba->add_question($question, $questiondata->maxmark);
 198         $questionsinuse[] = $question->id;
 199     }
 200
 201     // Start all the questions.
 202     if ($attempt->preview) {
 203         $variantoffset = rand(1, 100);
 204     } else {
 205         $variantoffset = $attemptnumber;
 206     }
 207     $quba->start_all_questions(
 208             new question_variant_pseudorandom_no_repeats_strategy($variantoffset), $timenow);
 209
 210     // Update attempt layout.
 211     $newlayout = array();
 212     foreach (explode(',', $attempt->layout) as $qid) {
 213         if ($qid != 0) {
 214             $newlayout[] = $idstoslots[$qid];
 215         } else {
 216             $newlayout[] = 0;
 217         }
 218     }
 219     $attempt->layout = implode(',', $newlayout);
 220
 221 } else {
 222     // Starting a subsequent attempt in each attempt builds on last mode.
 223
 224     $oldquba = question_engine::load_questions_usage_by_activity($lastattempt->uniqueid);
 225
 226     $oldnumberstonew = array();
 227     foreach ($oldquba->get_attempt_iterator() as $oldslot => $oldqa) {
 228         $newslot = $quba->add_question($oldqa->get_question(), $oldqa->get_max_mark());
 229
 230         $quba->start_question_based_on($newslot, $oldqa);
 231
 232         $oldnumberstonew[$oldslot] = $newslot;
 233     }
 234
 235     // Update attempt layout.
 236     $newlayout = array();
 237     foreach (explode(',', $lastattempt->layout) as $oldslot) {
 238         if ($oldslot != 0) {
 239             $newlayout[] = $oldnumberstonew[$oldslot];
 240         } else {
 241             $newlayout[] = 0;
 242         }
 243     }
 244     $attempt->layout = implode(',', $newlayout);
 245 }
 246
 247 // Save the attempt in the database.
 248 $transaction = $DB->start_delegated_transaction();
 249 question_engine::save_questions_usage_by_activity($quba);
 250 $attempt->uniqueid = $quba->get_id();
 251 $attempt->id = $DB->insert_record('quiz_attempts', $attempt);
 252
 253 // Log the new attempt.
 254 if ($attempt->preview) {
 255     add_to_log($course->id, 'quiz', 'preview', 'view.php?id=' . $quizobj->get_cmid(),
 256             $quizobj->get_quizid(), $quizobj->get_cmid());
 257 } else {
 258     add_to_log($course->id, 'quiz', 'attempt', 'review.php?attempt=' . $attempt->id,
 259             $quizobj->get_quizid(), $quizobj->get_cmid());
 260 }
 261
 262 // Trigger event.
 263 $eventdata = new stdClass();
 264 $eventdata->component = 'mod_quiz';
 265 $eventdata->attemptid = $attempt->id;
 266 $eventdata->timestart = $attempt->timestart;
 267 $eventdata->timestamp = $attempt->timestart;
 268 $eventdata->userid    = $attempt->userid;
 269 $eventdata->quizid    = $quizobj->get_quizid();
 270 $eventdata->cmid      = $quizobj->get_cmid();
 271 $eventdata->courseid  = $quizobj->get_courseid();
 272 events_trigger('quiz_attempt_started', $eventdata);
 273
 274 $transaction->allow_commit();
 275
 276 // Redirect to the attempt page.
 277 redirect($quizobj->attempt_url($attempt->id, $page));