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  • Bug fixes for general core bugs in 3.11.x will end 9 May 2022 (12 months).
  • Bug fixes for security issues in 3.11.x will end 14 November 2022 (18 months).
  • PHP version: minimum PHP 7.3.0 Note: minimum PHP version has increased since Moodle 3.10. PHP 7.4.x is supported too.
  • /mod/quiz/ -> lib.php (source)

    Differences Between: [Versions 310 and 311] [Versions 35 and 311] [Versions 36 and 311] [Versions 37 and 311] [Versions 38 and 311] [Versions 39 and 311]

       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   * Library of functions for the quiz module.
      19   *
      20   * This contains functions that are called also from outside the quiz module
      21   * Functions that are only called by the quiz module itself are in {@link locallib.php}
      22   *
      23   * @package    mod_quiz
      24   * @copyright  1999 onwards Martin Dougiamas {@link http://moodle.com}
      25   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
      26   */
      27  
      28  
      29  defined('MOODLE_INTERNAL') || die();
      30  
      31  require_once($CFG->dirroot . '/calendar/lib.php');
      32  
      33  
      34  /**#@+
      35   * Option controlling what options are offered on the quiz settings form.
      36   */
      37  define('QUIZ_MAX_ATTEMPT_OPTION', 10);
      38  define('QUIZ_MAX_QPP_OPTION', 50);
      39  define('QUIZ_MAX_DECIMAL_OPTION', 5);
      40  define('QUIZ_MAX_Q_DECIMAL_OPTION', 7);
      41  /**#@-*/
      42  
      43  /**#@+
      44   * Options determining how the grades from individual attempts are combined to give
      45   * the overall grade for a user
      46   */
      47  define('QUIZ_GRADEHIGHEST', '1');
      48  define('QUIZ_GRADEAVERAGE', '2');
      49  define('QUIZ_ATTEMPTFIRST', '3');
      50  define('QUIZ_ATTEMPTLAST',  '4');
      51  /**#@-*/
      52  
      53  /**
      54   * @var int If start and end date for the quiz are more than this many seconds apart
      55   * they will be represented by two separate events in the calendar
      56   */
      57  define('QUIZ_MAX_EVENT_LENGTH', 5*24*60*60); // 5 days.
      58  
      59  /**#@+
      60   * Options for navigation method within quizzes.
      61   */
      62  define('QUIZ_NAVMETHOD_FREE', 'free');
      63  define('QUIZ_NAVMETHOD_SEQ',  'sequential');
      64  /**#@-*/
      65  
      66  /**
      67   * Event types.
      68   */
      69  define('QUIZ_EVENT_TYPE_OPEN', 'open');
      70  define('QUIZ_EVENT_TYPE_CLOSE', 'close');
      71  
      72  require_once (__DIR__ . '/deprecatedlib.php');
      73  
      74  /**
      75   * Given an object containing all the necessary data,
      76   * (defined by the form in mod_form.php) this function
      77   * will create a new instance and return the id number
      78   * of the new instance.
      79   *
      80   * @param object $quiz the data that came from the form.
      81   * @return mixed the id of the new instance on success,
      82   *          false or a string error message on failure.
      83   */
      84  function quiz_add_instance($quiz) {
      85      global $DB;
      86      $cmid = $quiz->coursemodule;
      87  
      88      // Process the options from the form.
      89      $quiz->timecreated = time();
      90      $result = quiz_process_options($quiz);
      91      if ($result && is_string($result)) {
      92          return $result;
      93      }
      94  
      95      // Try to store it in the database.
      96      $quiz->id = $DB->insert_record('quiz', $quiz);
      97  
      98      // Create the first section for this quiz.
      99      $DB->insert_record('quiz_sections', array('quizid' => $quiz->id,
     100              'firstslot' => 1, 'heading' => '', 'shufflequestions' => 0));
     101  
     102      // Do the processing required after an add or an update.
     103      quiz_after_add_or_update($quiz);
     104  
     105      return $quiz->id;
     106  }
     107  
     108  /**
     109   * Given an object containing all the necessary data,
     110   * (defined by the form in mod_form.php) this function
     111   * will update an existing instance with new data.
     112   *
     113   * @param object $quiz the data that came from the form.
     114   * @return mixed true on success, false or a string error message on failure.
     115   */
     116  function quiz_update_instance($quiz, $mform) {
     117      global $CFG, $DB;
     118      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
     119  
     120      // Process the options from the form.
     121      $result = quiz_process_options($quiz);
     122      if ($result && is_string($result)) {
     123          return $result;
     124      }
     125  
     126      // Get the current value, so we can see what changed.
     127      $oldquiz = $DB->get_record('quiz', array('id' => $quiz->instance));
     128  
     129      // We need two values from the existing DB record that are not in the form,
     130      // in some of the function calls below.
     131      $quiz->sumgrades = $oldquiz->sumgrades;
     132      $quiz->grade     = $oldquiz->grade;
     133  
     134      // Update the database.
     135      $quiz->id = $quiz->instance;
     136      $DB->update_record('quiz', $quiz);
     137  
     138      // Do the processing required after an add or an update.
     139      quiz_after_add_or_update($quiz);
     140  
     141      if ($oldquiz->grademethod != $quiz->grademethod) {
     142          quiz_update_all_final_grades($quiz);
     143          quiz_update_grades($quiz);
     144      }
     145  
     146      $quizdateschanged = $oldquiz->timelimit   != $quiz->timelimit
     147                       || $oldquiz->timeclose   != $quiz->timeclose
     148                       || $oldquiz->graceperiod != $quiz->graceperiod;
     149      if ($quizdateschanged) {
     150          quiz_update_open_attempts(array('quizid' => $quiz->id));
     151      }
     152  
     153      // Delete any previous preview attempts.
     154      quiz_delete_previews($quiz);
     155  
     156      // Repaginate, if asked to.
     157      if (!empty($quiz->repaginatenow)) {
     158          quiz_repaginate_questions($quiz->id, $quiz->questionsperpage);
     159      }
     160  
     161      return true;
     162  }
     163  
     164  /**
     165   * Given an ID of an instance of this module,
     166   * this function will permanently delete the instance
     167   * and any data that depends on it.
     168   *
     169   * @param int $id the id of the quiz to delete.
     170   * @return bool success or failure.
     171   */
     172  function quiz_delete_instance($id) {
     173      global $DB;
     174  
     175      $quiz = $DB->get_record('quiz', array('id' => $id), '*', MUST_EXIST);
     176  
     177      quiz_delete_all_attempts($quiz);
     178      quiz_delete_all_overrides($quiz);
     179  
     180      // Look for random questions that may no longer be used when this quiz is gone.
     181      $sql = "SELECT q.id
     182                FROM {quiz_slots} slot
     183                JOIN {question} q ON q.id = slot.questionid
     184               WHERE slot.quizid = ? AND q.qtype = ?";
     185      $questionids = $DB->get_fieldset_sql($sql, array($quiz->id, 'random'));
     186  
     187      // We need to do the following deletes before we try and delete randoms, otherwise they would still be 'in use'.
     188      $quizslots = $DB->get_fieldset_select('quiz_slots', 'id', 'quizid = ?', array($quiz->id));
     189      $DB->delete_records_list('quiz_slot_tags', 'slotid', $quizslots);
     190      $DB->delete_records('quiz_slots', array('quizid' => $quiz->id));
     191      $DB->delete_records('quiz_sections', array('quizid' => $quiz->id));
     192  
     193      foreach ($questionids as $questionid) {
     194          question_delete_question($questionid);
     195      }
     196  
     197      $DB->delete_records('quiz_feedback', array('quizid' => $quiz->id));
     198  
     199      quiz_access_manager::delete_settings($quiz);
     200  
     201      $events = $DB->get_records('event', array('modulename' => 'quiz', 'instance' => $quiz->id));
     202      foreach ($events as $event) {
     203          $event = calendar_event::load($event);
     204          $event->delete();
     205      }
     206  
     207      quiz_grade_item_delete($quiz);
     208      // We must delete the module record after we delete the grade item.
     209      $DB->delete_records('quiz', array('id' => $quiz->id));
     210  
     211      return true;
     212  }
     213  
     214  /**
     215   * Deletes a quiz override from the database and clears any corresponding calendar events
     216   *
     217   * @param object $quiz The quiz object.
     218   * @param int $overrideid The id of the override being deleted
     219   * @param bool $log Whether to trigger logs.
     220   * @return bool true on success
     221   */
     222  function quiz_delete_override($quiz, $overrideid, $log = true) {
     223      global $DB;
     224  
     225      if (!isset($quiz->cmid)) {
     226          $cm = get_coursemodule_from_instance('quiz', $quiz->id, $quiz->course);
     227          $quiz->cmid = $cm->id;
     228      }
     229  
     230      $override = $DB->get_record('quiz_overrides', array('id' => $overrideid), '*', MUST_EXIST);
     231  
     232      // Delete the events.
     233      if (isset($override->groupid)) {
     234          // Create the search array for a group override.
     235          $eventsearcharray = array('modulename' => 'quiz',
     236              'instance' => $quiz->id, 'groupid' => (int)$override->groupid);
     237          $cachekey = "{$quiz->id}_g_{$override->groupid}";
     238      } else {
     239          // Create the search array for a user override.
     240          $eventsearcharray = array('modulename' => 'quiz',
     241              'instance' => $quiz->id, 'userid' => (int)$override->userid);
     242          $cachekey = "{$quiz->id}_u_{$override->userid}";
     243      }
     244      $events = $DB->get_records('event', $eventsearcharray);
     245      foreach ($events as $event) {
     246          $eventold = calendar_event::load($event);
     247          $eventold->delete();
     248      }
     249  
     250      $DB->delete_records('quiz_overrides', array('id' => $overrideid));
     251      cache::make('mod_quiz', 'overrides')->delete($cachekey);
     252  
     253      if ($log) {
     254          // Set the common parameters for one of the events we will be triggering.
     255          $params = array(
     256              'objectid' => $override->id,
     257              'context' => context_module::instance($quiz->cmid),
     258              'other' => array(
     259                  'quizid' => $override->quiz
     260              )
     261          );
     262          // Determine which override deleted event to fire.
     263          if (!empty($override->userid)) {
     264              $params['relateduserid'] = $override->userid;
     265              $event = \mod_quiz\event\user_override_deleted::create($params);
     266          } else {
     267              $params['other']['groupid'] = $override->groupid;
     268              $event = \mod_quiz\event\group_override_deleted::create($params);
     269          }
     270  
     271          // Trigger the override deleted event.
     272          $event->add_record_snapshot('quiz_overrides', $override);
     273          $event->trigger();
     274      }
     275  
     276      return true;
     277  }
     278  
     279  /**
     280   * Deletes all quiz overrides from the database and clears any corresponding calendar events
     281   *
     282   * @param object $quiz The quiz object.
     283   * @param bool $log Whether to trigger logs.
     284   */
     285  function quiz_delete_all_overrides($quiz, $log = true) {
     286      global $DB;
     287  
     288      $overrides = $DB->get_records('quiz_overrides', array('quiz' => $quiz->id), 'id');
     289      foreach ($overrides as $override) {
     290          quiz_delete_override($quiz, $override->id, $log);
     291      }
     292  }
     293  
     294  /**
     295   * Updates a quiz object with override information for a user.
     296   *
     297   * Algorithm:  For each quiz setting, if there is a matching user-specific override,
     298   *   then use that otherwise, if there are group-specific overrides, return the most
     299   *   lenient combination of them.  If neither applies, leave the quiz setting unchanged.
     300   *
     301   *   Special case: if there is more than one password that applies to the user, then
     302   *   quiz->extrapasswords will contain an array of strings giving the remaining
     303   *   passwords.
     304   *
     305   * @param object $quiz The quiz object.
     306   * @param int $userid The userid.
     307   * @return object $quiz The updated quiz object.
     308   */
     309  function quiz_update_effective_access($quiz, $userid) {
     310      global $DB;
     311  
     312      // Check for user override.
     313      $override = $DB->get_record('quiz_overrides', array('quiz' => $quiz->id, 'userid' => $userid));
     314  
     315      if (!$override) {
     316          $override = new stdClass();
     317          $override->timeopen = null;
     318          $override->timeclose = null;
     319          $override->timelimit = null;
     320          $override->attempts = null;
     321          $override->password = null;
     322      }
     323  
     324      // Check for group overrides.
     325      $groupings = groups_get_user_groups($quiz->course, $userid);
     326  
     327      if (!empty($groupings[0])) {
     328          // Select all overrides that apply to the User's groups.
     329          list($extra, $params) = $DB->get_in_or_equal(array_values($groupings[0]));
     330          $sql = "SELECT * FROM {quiz_overrides}
     331                  WHERE groupid $extra AND quiz = ?";
     332          $params[] = $quiz->id;
     333          $records = $DB->get_records_sql($sql, $params);
     334  
     335          // Combine the overrides.
     336          $opens = array();
     337          $closes = array();
     338          $limits = array();
     339          $attempts = array();
     340          $passwords = array();
     341  
     342          foreach ($records as $gpoverride) {
     343              if (isset($gpoverride->timeopen)) {
     344                  $opens[] = $gpoverride->timeopen;
     345              }
     346              if (isset($gpoverride->timeclose)) {
     347                  $closes[] = $gpoverride->timeclose;
     348              }
     349              if (isset($gpoverride->timelimit)) {
     350                  $limits[] = $gpoverride->timelimit;
     351              }
     352              if (isset($gpoverride->attempts)) {
     353                  $attempts[] = $gpoverride->attempts;
     354              }
     355              if (isset($gpoverride->password)) {
     356                  $passwords[] = $gpoverride->password;
     357              }
     358          }
     359          // If there is a user override for a setting, ignore the group override.
     360          if (is_null($override->timeopen) && count($opens)) {
     361              $override->timeopen = min($opens);
     362          }
     363          if (is_null($override->timeclose) && count($closes)) {
     364              if (in_array(0, $closes)) {
     365                  $override->timeclose = 0;
     366              } else {
     367                  $override->timeclose = max($closes);
     368              }
     369          }
     370          if (is_null($override->timelimit) && count($limits)) {
     371              if (in_array(0, $limits)) {
     372                  $override->timelimit = 0;
     373              } else {
     374                  $override->timelimit = max($limits);
     375              }
     376          }
     377          if (is_null($override->attempts) && count($attempts)) {
     378              if (in_array(0, $attempts)) {
     379                  $override->attempts = 0;
     380              } else {
     381                  $override->attempts = max($attempts);
     382              }
     383          }
     384          if (is_null($override->password) && count($passwords)) {
     385              $override->password = array_shift($passwords);
     386              if (count($passwords)) {
     387                  $override->extrapasswords = $passwords;
     388              }
     389          }
     390  
     391      }
     392  
     393      // Merge with quiz defaults.
     394      $keys = array('timeopen', 'timeclose', 'timelimit', 'attempts', 'password', 'extrapasswords');
     395      foreach ($keys as $key) {
     396          if (isset($override->{$key})) {
     397              $quiz->{$key} = $override->{$key};
     398          }
     399      }
     400  
     401      return $quiz;
     402  }
     403  
     404  /**
     405   * Delete all the attempts belonging to a quiz.
     406   *
     407   * @param object $quiz The quiz object.
     408   */
     409  function quiz_delete_all_attempts($quiz) {
     410      global $CFG, $DB;
     411      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
     412      question_engine::delete_questions_usage_by_activities(new qubaids_for_quiz($quiz->id));
     413      $DB->delete_records('quiz_attempts', array('quiz' => $quiz->id));
     414      $DB->delete_records('quiz_grades', array('quiz' => $quiz->id));
     415  }
     416  
     417  /**
     418   * Delete all the attempts belonging to a user in a particular quiz.
     419   *
     420   * @param object $quiz The quiz object.
     421   * @param object $user The user object.
     422   */
     423  function quiz_delete_user_attempts($quiz, $user) {
     424      global $CFG, $DB;
     425      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
     426      question_engine::delete_questions_usage_by_activities(new qubaids_for_quiz_user($quiz->get_quizid(), $user->id));
     427      $params = [
     428          'quiz' => $quiz->get_quizid(),
     429          'userid' => $user->id,
     430      ];
     431      $DB->delete_records('quiz_attempts', $params);
     432      $DB->delete_records('quiz_grades', $params);
     433  }
     434  
     435  /**
     436   * Get the best current grade for a particular user in a quiz.
     437   *
     438   * @param object $quiz the quiz settings.
     439   * @param int $userid the id of the user.
     440   * @return float the user's current grade for this quiz, or null if this user does
     441   * not have a grade on this quiz.
     442   */
     443  function quiz_get_best_grade($quiz, $userid) {
     444      global $DB;
     445      $grade = $DB->get_field('quiz_grades', 'grade',
     446              array('quiz' => $quiz->id, 'userid' => $userid));
     447  
     448      // Need to detect errors/no result, without catching 0 grades.
     449      if ($grade === false) {
     450          return null;
     451      }
     452  
     453      return $grade + 0; // Convert to number.
     454  }
     455  
     456  /**
     457   * Is this a graded quiz? If this method returns true, you can assume that
     458   * $quiz->grade and $quiz->sumgrades are non-zero (for example, if you want to
     459   * divide by them).
     460   *
     461   * @param object $quiz a row from the quiz table.
     462   * @return bool whether this is a graded quiz.
     463   */
     464  function quiz_has_grades($quiz) {
     465      return $quiz->grade >= 0.000005 && $quiz->sumgrades >= 0.000005;
     466  }
     467  
     468  /**
     469   * Does this quiz allow multiple tries?
     470   *
     471   * @return bool
     472   */
     473  function quiz_allows_multiple_tries($quiz) {
     474      $bt = question_engine::get_behaviour_type($quiz->preferredbehaviour);
     475      return $bt->allows_multiple_submitted_responses();
     476  }
     477  
     478  /**
     479   * Return a small object with summary information about what a
     480   * user has done with a given particular instance of this module
     481   * Used for user activity reports.
     482   * $return->time = the time they did it
     483   * $return->info = a short text description
     484   *
     485   * @param object $course
     486   * @param object $user
     487   * @param object $mod
     488   * @param object $quiz
     489   * @return object|null
     490   */
     491  function quiz_user_outline($course, $user, $mod, $quiz) {
     492      global $DB, $CFG;
     493      require_once($CFG->libdir . '/gradelib.php');
     494      $grades = grade_get_grades($course->id, 'mod', 'quiz', $quiz->id, $user->id);
     495  
     496      if (empty($grades->items[0]->grades)) {
     497          return null;
     498      } else {
     499          $grade = reset($grades->items[0]->grades);
     500      }
     501  
     502      $result = new stdClass();
     503      // If the user can't see hidden grades, don't return that information.
     504      $gitem = grade_item::fetch(array('id' => $grades->items[0]->id));
     505      if (!$gitem->hidden || has_capability('moodle/grade:viewhidden', context_course::instance($course->id))) {
     506          $result->info = get_string('gradenoun') . ': ' . $grade->str_long_grade;
     507      } else {
     508          $result->info = get_string('gradenoun') . ': ' . get_string('hidden', 'grades');
     509      }
     510  
     511      $result->time = grade_get_date_for_user_grade($grade, $user);
     512  
     513      return $result;
     514  }
     515  
     516  /**
     517   * Print a detailed representation of what a  user has done with
     518   * a given particular instance of this module, for user activity reports.
     519   *
     520   * @param object $course
     521   * @param object $user
     522   * @param object $mod
     523   * @param object $quiz
     524   * @return bool
     525   */
     526  function quiz_user_complete($course, $user, $mod, $quiz) {
     527      global $DB, $CFG, $OUTPUT;
     528      require_once($CFG->libdir . '/gradelib.php');
     529      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
     530  
     531      $grades = grade_get_grades($course->id, 'mod', 'quiz', $quiz->id, $user->id);
     532      if (!empty($grades->items[0]->grades)) {
     533          $grade = reset($grades->items[0]->grades);
     534          // If the user can't see hidden grades, don't return that information.
     535          $gitem = grade_item::fetch(array('id' => $grades->items[0]->id));
     536          if (!$gitem->hidden || has_capability('moodle/grade:viewhidden', context_course::instance($course->id))) {
     537              echo $OUTPUT->container(get_string('gradenoun').': '.$grade->str_long_grade);
     538              if ($grade->str_feedback) {
     539                  echo $OUTPUT->container(get_string('feedback').': '.$grade->str_feedback);
     540              }
     541          } else {
     542              echo $OUTPUT->container(get_string('gradenoun') . ': ' . get_string('hidden', 'grades'));
     543              if ($grade->str_feedback) {
     544                  echo $OUTPUT->container(get_string('feedback').': '.get_string('hidden', 'grades'));
     545              }
     546          }
     547      }
     548  
     549      if ($attempts = $DB->get_records('quiz_attempts',
     550              array('userid' => $user->id, 'quiz' => $quiz->id), 'attempt')) {
     551          foreach ($attempts as $attempt) {
     552              echo get_string('attempt', 'quiz', $attempt->attempt) . ': ';
     553              if ($attempt->state != quiz_attempt::FINISHED) {
     554                  echo quiz_attempt_state_name($attempt->state);
     555              } else {
     556                  if (!isset($gitem)) {
     557                      if (!empty($grades->items[0]->grades)) {
     558                          $gitem = grade_item::fetch(array('id' => $grades->items[0]->id));
     559                      } else {
     560                          $gitem = new stdClass();
     561                          $gitem->hidden = true;
     562                      }
     563                  }
     564                  if (!$gitem->hidden || has_capability('moodle/grade:viewhidden', context_course::instance($course->id))) {
     565                      echo quiz_format_grade($quiz, $attempt->sumgrades) . '/' . quiz_format_grade($quiz, $quiz->sumgrades);
     566                  } else {
     567                      echo get_string('hidden', 'grades');
     568                  }
     569                  echo ' - '.userdate($attempt->timefinish).'<br />';
     570              }
     571          }
     572      } else {
     573          print_string('noattempts', 'quiz');
     574      }
     575  
     576      return true;
     577  }
     578  
     579  
     580  /**
     581   * @param int|array $quizids A quiz ID, or an array of quiz IDs.
     582   * @param int $userid the userid.
     583   * @param string $status 'all', 'finished' or 'unfinished' to control
     584   * @param bool $includepreviews
     585   * @return an array of all the user's attempts at this quiz. Returns an empty
     586   *      array if there are none.
     587   */
     588  function quiz_get_user_attempts($quizids, $userid, $status = 'finished', $includepreviews = false) {
     589      global $DB, $CFG;
     590      // TODO MDL-33071 it is very annoying to have to included all of locallib.php
     591      // just to get the quiz_attempt::FINISHED constants, but I will try to sort
     592      // that out properly for Moodle 2.4. For now, I will just do a quick fix for
     593      // MDL-33048.
     594      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
     595  
     596      $params = array();
     597      switch ($status) {
     598          case 'all':
     599              $statuscondition = '';
     600              break;
     601  
     602          case 'finished':
     603              $statuscondition = ' AND state IN (:state1, :state2)';
     604              $params['state1'] = quiz_attempt::FINISHED;
     605              $params['state2'] = quiz_attempt::ABANDONED;
     606              break;
     607  
     608          case 'unfinished':
     609              $statuscondition = ' AND state IN (:state1, :state2)';
     610              $params['state1'] = quiz_attempt::IN_PROGRESS;
     611              $params['state2'] = quiz_attempt::OVERDUE;
     612              break;
     613      }
     614  
     615      $quizids = (array) $quizids;
     616      list($insql, $inparams) = $DB->get_in_or_equal($quizids, SQL_PARAMS_NAMED);
     617      $params += $inparams;
     618      $params['userid'] = $userid;
     619  
     620      $previewclause = '';
     621      if (!$includepreviews) {
     622          $previewclause = ' AND preview = 0';
     623      }
     624  
     625      return $DB->get_records_select('quiz_attempts',
     626              "quiz $insql AND userid = :userid" . $previewclause . $statuscondition,
     627              $params, 'quiz, attempt ASC');
     628  }
     629  
     630  /**
     631   * Return grade for given user or all users.
     632   *
     633   * @param int $quizid id of quiz
     634   * @param int $userid optional user id, 0 means all users
     635   * @return array array of grades, false if none. These are raw grades. They should
     636   * be processed with quiz_format_grade for display.
     637   */
     638  function quiz_get_user_grades($quiz, $userid = 0) {
     639      global $CFG, $DB;
     640  
     641      $params = array($quiz->id);
     642      $usertest = '';
     643      if ($userid) {
     644          $params[] = $userid;
     645          $usertest = 'AND u.id = ?';
     646      }
     647      return $DB->get_records_sql("
     648              SELECT
     649                  u.id,
     650                  u.id AS userid,
     651                  qg.grade AS rawgrade,
     652                  qg.timemodified AS dategraded,
     653                  MAX(qa.timefinish) AS datesubmitted
     654  
     655              FROM {user} u
     656              JOIN {quiz_grades} qg ON u.id = qg.userid
     657              JOIN {quiz_attempts} qa ON qa.quiz = qg.quiz AND qa.userid = u.id
     658  
     659              WHERE qg.quiz = ?
     660              $usertest
     661              GROUP BY u.id, qg.grade, qg.timemodified", $params);
     662  }
     663  
     664  /**
     665   * Round a grade to to the correct number of decimal places, and format it for display.
     666   *
     667   * @param object $quiz The quiz table row, only $quiz->decimalpoints is used.
     668   * @param float $grade The grade to round.
     669   * @return float
     670   */
     671  function quiz_format_grade($quiz, $grade) {
     672      if (is_null($grade)) {
     673          return get_string('notyetgraded', 'quiz');
     674      }
     675      return format_float($grade, $quiz->decimalpoints);
     676  }
     677  
     678  /**
     679   * Determine the correct number of decimal places required to format a grade.
     680   *
     681   * @param object $quiz The quiz table row, only $quiz->decimalpoints is used.
     682   * @return integer
     683   */
     684  function quiz_get_grade_format($quiz) {
     685      if (empty($quiz->questiondecimalpoints)) {
     686          $quiz->questiondecimalpoints = -1;
     687      }
     688  
     689      if ($quiz->questiondecimalpoints == -1) {
     690          return $quiz->decimalpoints;
     691      }
     692  
     693      return $quiz->questiondecimalpoints;
     694  }
     695  
     696  /**
     697   * Round a grade to the correct number of decimal places, and format it for display.
     698   *
     699   * @param object $quiz The quiz table row, only $quiz->decimalpoints is used.
     700   * @param float $grade The grade to round.
     701   * @return float
     702   */
     703  function quiz_format_question_grade($quiz, $grade) {
     704      return format_float($grade, quiz_get_grade_format($quiz));
     705  }
     706  
     707  /**
     708   * Update grades in central gradebook
     709   *
     710   * @category grade
     711   * @param object $quiz the quiz settings.
     712   * @param int $userid specific user only, 0 means all users.
     713   * @param bool $nullifnone If a single user is specified and $nullifnone is true a grade item with a null rawgrade will be inserted
     714   */
     715  function quiz_update_grades($quiz, $userid = 0, $nullifnone = true) {
     716      global $CFG, $DB;
     717      require_once($CFG->libdir . '/gradelib.php');
     718  
     719      if ($quiz->grade == 0) {
     720          quiz_grade_item_update($quiz);
     721  
     722      } else if ($grades = quiz_get_user_grades($quiz, $userid)) {
     723          quiz_grade_item_update($quiz, $grades);
     724  
     725      } else if ($userid && $nullifnone) {
     726          $grade = new stdClass();
     727          $grade->userid = $userid;
     728          $grade->rawgrade = null;
     729          quiz_grade_item_update($quiz, $grade);
     730  
     731      } else {
     732          quiz_grade_item_update($quiz);
     733      }
     734  }
     735  
     736  /**
     737   * Create or update the grade item for given quiz
     738   *
     739   * @category grade
     740   * @param object $quiz object with extra cmidnumber
     741   * @param mixed $grades optional array/object of grade(s); 'reset' means reset grades in gradebook
     742   * @return int 0 if ok, error code otherwise
     743   */
     744  function quiz_grade_item_update($quiz, $grades = null) {
     745      global $CFG, $OUTPUT;
     746      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
     747      require_once($CFG->libdir . '/gradelib.php');
     748  
     749      if (property_exists($quiz, 'cmidnumber')) { // May not be always present.
     750          $params = array('itemname' => $quiz->name, 'idnumber' => $quiz->cmidnumber);
     751      } else {
     752          $params = array('itemname' => $quiz->name);
     753      }
     754  
     755      if ($quiz->grade > 0) {
     756          $params['gradetype'] = GRADE_TYPE_VALUE;
     757          $params['grademax']  = $quiz->grade;
     758          $params['grademin']  = 0;
     759  
     760      } else {
     761          $params['gradetype'] = GRADE_TYPE_NONE;
     762      }
     763  
     764      // What this is trying to do:
     765      // 1. If the quiz is set to not show grades while the quiz is still open,
     766      //    and is set to show grades after the quiz is closed, then create the
     767      //    grade_item with a show-after date that is the quiz close date.
     768      // 2. If the quiz is set to not show grades at either of those times,
     769      //    create the grade_item as hidden.
     770      // 3. If the quiz is set to show grades, create the grade_item visible.
     771      $openreviewoptions = mod_quiz_display_options::make_from_quiz($quiz,
     772              mod_quiz_display_options::LATER_WHILE_OPEN);
     773      $closedreviewoptions = mod_quiz_display_options::make_from_quiz($quiz,
     774              mod_quiz_display_options::AFTER_CLOSE);
     775      if ($openreviewoptions->marks < question_display_options::MARK_AND_MAX &&
     776              $closedreviewoptions->marks < question_display_options::MARK_AND_MAX) {
     777          $params['hidden'] = 1;
     778  
     779      } else if ($openreviewoptions->marks < question_display_options::MARK_AND_MAX &&
     780              $closedreviewoptions->marks >= question_display_options::MARK_AND_MAX) {
     781          if ($quiz->timeclose) {
     782              $params['hidden'] = $quiz->timeclose;
     783          } else {
     784              $params['hidden'] = 1;
     785          }
     786  
     787      } else {
     788          // Either
     789          // a) both open and closed enabled
     790          // b) open enabled, closed disabled - we can not "hide after",
     791          //    grades are kept visible even after closing.
     792          $params['hidden'] = 0;
     793      }
     794  
     795      if (!$params['hidden']) {
     796          // If the grade item is not hidden by the quiz logic, then we need to
     797          // hide it if the quiz is hidden from students.
     798          if (property_exists($quiz, 'visible')) {
     799              // Saving the quiz form, and cm not yet updated in the database.
     800              $params['hidden'] = !$quiz->visible;
     801          } else {
     802              $cm = get_coursemodule_from_instance('quiz', $quiz->id);
     803              $params['hidden'] = !$cm->visible;
     804          }
     805      }
     806  
     807      if ($grades  === 'reset') {
     808          $params['reset'] = true;
     809          $grades = null;
     810      }
     811  
     812      $gradebook_grades = grade_get_grades($quiz->course, 'mod', 'quiz', $quiz->id);
     813      if (!empty($gradebook_grades->items)) {
     814          $grade_item = $gradebook_grades->items[0];
     815          if ($grade_item->locked) {
     816              // NOTE: this is an extremely nasty hack! It is not a bug if this confirmation fails badly. --skodak.
     817              $confirm_regrade = optional_param('confirm_regrade', 0, PARAM_INT);
     818              if (!$confirm_regrade) {
     819                  if (!AJAX_SCRIPT) {
     820                      $message = get_string('gradeitemislocked', 'grades');
     821                      $back_link = $CFG->wwwroot . '/mod/quiz/report.php?q=' . $quiz->id .
     822                              '&amp;mode=overview';
     823                      $regrade_link = qualified_me() . '&amp;confirm_regrade=1';
     824                      echo $OUTPUT->box_start('generalbox', 'notice');
     825                      echo '<p>'. $message .'</p>';
     826                      echo $OUTPUT->container_start('buttons');
     827                      echo $OUTPUT->single_button($regrade_link, get_string('regradeanyway', 'grades'));
     828                      echo $OUTPUT->single_button($back_link,  get_string('cancel'));
     829                      echo $OUTPUT->container_end();
     830                      echo $OUTPUT->box_end();
     831                  }
     832                  return GRADE_UPDATE_ITEM_LOCKED;
     833              }
     834          }
     835      }
     836  
     837      return grade_update('mod/quiz', $quiz->course, 'mod', 'quiz', $quiz->id, 0, $grades, $params);
     838  }
     839  
     840  /**
     841   * Delete grade item for given quiz
     842   *
     843   * @category grade
     844   * @param object $quiz object
     845   * @return object quiz
     846   */
     847  function quiz_grade_item_delete($quiz) {
     848      global $CFG;
     849      require_once($CFG->libdir . '/gradelib.php');
     850  
     851      return grade_update('mod/quiz', $quiz->course, 'mod', 'quiz', $quiz->id, 0,
     852              null, array('deleted' => 1));
     853  }
     854  
     855  /**
     856   * This standard function will check all instances of this module
     857   * and make sure there are up-to-date events created for each of them.
     858   * If courseid = 0, then every quiz event in the site is checked, else
     859   * only quiz events belonging to the course specified are checked.
     860   * This function is used, in its new format, by restore_refresh_events()
     861   *
     862   * @param int $courseid
     863   * @param int|stdClass $instance Quiz module instance or ID.
     864   * @param int|stdClass $cm Course module object or ID (not used in this module).
     865   * @return bool
     866   */
     867  function quiz_refresh_events($courseid = 0, $instance = null, $cm = null) {
     868      global $DB;
     869  
     870      // If we have instance information then we can just update the one event instead of updating all events.
     871      if (isset($instance)) {
     872          if (!is_object($instance)) {
     873              $instance = $DB->get_record('quiz', array('id' => $instance), '*', MUST_EXIST);
     874          }
     875          quiz_update_events($instance);
     876          return true;
     877      }
     878  
     879      if ($courseid == 0) {
     880          if (!$quizzes = $DB->get_records('quiz')) {
     881              return true;
     882          }
     883      } else {
     884          if (!$quizzes = $DB->get_records('quiz', array('course' => $courseid))) {
     885              return true;
     886          }
     887      }
     888  
     889      foreach ($quizzes as $quiz) {
     890          quiz_update_events($quiz);
     891      }
     892  
     893      return true;
     894  }
     895  
     896  /**
     897   * Returns all quiz graded users since a given time for specified quiz
     898   */
     899  function quiz_get_recent_mod_activity(&$activities, &$index, $timestart,
     900          $courseid, $cmid, $userid = 0, $groupid = 0) {
     901      global $CFG, $USER, $DB;
     902      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
     903  
     904      $course = get_course($courseid);
     905      $modinfo = get_fast_modinfo($course);
     906  
     907      $cm = $modinfo->cms[$cmid];
     908      $quiz = $DB->get_record('quiz', array('id' => $cm->instance));
     909  
     910      if ($userid) {
     911          $userselect = "AND u.id = :userid";
     912          $params['userid'] = $userid;
     913      } else {
     914          $userselect = '';
     915      }
     916  
     917      if ($groupid) {
     918          $groupselect = 'AND gm.groupid = :groupid';
     919          $groupjoin   = 'JOIN {groups_members} gm ON  gm.userid=u.id';
     920          $params['groupid'] = $groupid;
     921      } else {
     922          $groupselect = '';
     923          $groupjoin   = '';
     924      }
     925  
     926      $params['timestart'] = $timestart;
     927      $params['quizid'] = $quiz->id;
     928  
     929      $userfieldsapi = \core_user\fields::for_userpic();
     930      $ufields = $userfieldsapi->get_sql('u', false, '', 'useridagain', false)->selects;
     931      if (!$attempts = $DB->get_records_sql("
     932                SELECT qa.*,
     933                       {$ufields}
     934                  FROM {quiz_attempts} qa
     935                       JOIN {user} u ON u.id = qa.userid
     936                       $groupjoin
     937                 WHERE qa.timefinish > :timestart
     938                   AND qa.quiz = :quizid
     939                   AND qa.preview = 0
     940                       $userselect
     941                       $groupselect
     942              ORDER BY qa.timefinish ASC", $params)) {
     943          return;
     944      }
     945  
     946      $context         = context_module::instance($cm->id);
     947      $accessallgroups = has_capability('moodle/site:accessallgroups', $context);
     948      $viewfullnames   = has_capability('moodle/site:viewfullnames', $context);
     949      $grader          = has_capability('mod/quiz:viewreports', $context);
     950      $groupmode       = groups_get_activity_groupmode($cm, $course);
     951  
     952      $usersgroups = null;
     953      $aname = format_string($cm->name, true);
     954      foreach ($attempts as $attempt) {
     955          if ($attempt->userid != $USER->id) {
     956              if (!$grader) {
     957                  // Grade permission required.
     958                  continue;
     959              }
     960  
     961              if ($groupmode == SEPARATEGROUPS and !$accessallgroups) {
     962                  $usersgroups = groups_get_all_groups($course->id,
     963                          $attempt->userid, $cm->groupingid);
     964                  $usersgroups = array_keys($usersgroups);
     965                  if (!array_intersect($usersgroups, $modinfo->get_groups($cm->groupingid))) {
     966                      continue;
     967                  }
     968              }
     969          }
     970  
     971          $options = quiz_get_review_options($quiz, $attempt, $context);
     972  
     973          $tmpactivity = new stdClass();
     974  
     975          $tmpactivity->type       = 'quiz';
     976          $tmpactivity->cmid       = $cm->id;
     977          $tmpactivity->name       = $aname;
     978          $tmpactivity->sectionnum = $cm->sectionnum;
     979          $tmpactivity->timestamp  = $attempt->timefinish;
     980  
     981          $tmpactivity->content = new stdClass();
     982          $tmpactivity->content->attemptid = $attempt->id;
     983          $tmpactivity->content->attempt   = $attempt->attempt;
     984          if (quiz_has_grades($quiz) && $options->marks >= question_display_options::MARK_AND_MAX) {
     985              $tmpactivity->content->sumgrades = quiz_format_grade($quiz, $attempt->sumgrades);
     986              $tmpactivity->content->maxgrade  = quiz_format_grade($quiz, $quiz->sumgrades);
     987          } else {
     988              $tmpactivity->content->sumgrades = null;
     989              $tmpactivity->content->maxgrade  = null;
     990          }
     991  
     992          $tmpactivity->user = user_picture::unalias($attempt, null, 'useridagain');
     993          $tmpactivity->user->fullname  = fullname($tmpactivity->user, $viewfullnames);
     994  
     995          $activities[$index++] = $tmpactivity;
     996      }
     997  }
     998  
     999  function quiz_print_recent_mod_activity($activity, $courseid, $detail, $modnames) {
    1000      global $CFG, $OUTPUT;
    1001  
    1002      echo '<table border="0" cellpadding="3" cellspacing="0" class="forum-recent">';
    1003  
    1004      echo '<tr><td class="userpicture" valign="top">';
    1005      echo $OUTPUT->user_picture($activity->user, array('courseid' => $courseid));
    1006      echo '</td><td>';
    1007  
    1008      if ($detail) {
    1009          $modname = $modnames[$activity->type];
    1010          echo '<div class="title">';
    1011          echo $OUTPUT->image_icon('icon', $modname, $activity->type);
    1012          echo '<a href="' . $CFG->wwwroot . '/mod/quiz/view.php?id=' .
    1013                  $activity->cmid . '">' . $activity->name . '</a>';
    1014          echo '</div>';
    1015      }
    1016  
    1017      echo '<div class="grade">';
    1018      echo  get_string('attempt', 'quiz', $activity->content->attempt);
    1019      if (isset($activity->content->maxgrade)) {
    1020          $grades = $activity->content->sumgrades . ' / ' . $activity->content->maxgrade;
    1021          echo ': (<a href="' . $CFG->wwwroot . '/mod/quiz/review.php?attempt=' .
    1022                  $activity->content->attemptid . '">' . $grades . '</a>)';
    1023      }
    1024      echo '</div>';
    1025  
    1026      echo '<div class="user">';
    1027      echo '<a href="' . $CFG->wwwroot . '/user/view.php?id=' . $activity->user->id .
    1028              '&amp;course=' . $courseid . '">' . $activity->user->fullname .
    1029              '</a> - ' . userdate($activity->timestamp);
    1030      echo '</div>';
    1031  
    1032      echo '</td></tr></table>';
    1033  
    1034      return;
    1035  }
    1036  
    1037  /**
    1038   * Pre-process the quiz options form data, making any necessary adjustments.
    1039   * Called by add/update instance in this file.
    1040   *
    1041   * @param object $quiz The variables set on the form.
    1042   */
    1043  function quiz_process_options($quiz) {
    1044      global $CFG;
    1045      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
    1046      require_once($CFG->libdir . '/questionlib.php');
    1047  
    1048      $quiz->timemodified = time();
    1049  
    1050      // Quiz name.
    1051      if (!empty($quiz->name)) {
    1052          $quiz->name = trim($quiz->name);
    1053      }
    1054  
    1055      // Password field - different in form to stop browsers that remember passwords
    1056      // getting confused.
    1057      $quiz->password = $quiz->quizpassword;
    1058      unset($quiz->quizpassword);
    1059  
    1060      // Quiz feedback.
    1061      if (isset($quiz->feedbacktext)) {
    1062          // Clean up the boundary text.
    1063          for ($i = 0; $i < count($quiz->feedbacktext); $i += 1) {
    1064              if (empty($quiz->feedbacktext[$i]['text'])) {
    1065                  $quiz->feedbacktext[$i]['text'] = '';
    1066              } else {
    1067                  $quiz->feedbacktext[$i]['text'] = trim($quiz->feedbacktext[$i]['text']);
    1068              }
    1069          }
    1070  
    1071          // Check the boundary value is a number or a percentage, and in range.
    1072          $i = 0;
    1073          while (!empty($quiz->feedbackboundaries[$i])) {
    1074              $boundary = trim($quiz->feedbackboundaries[$i]);
    1075              if (!is_numeric($boundary)) {
    1076                  if (strlen($boundary) > 0 && $boundary[strlen($boundary) - 1] == '%') {
    1077                      $boundary = trim(substr($boundary, 0, -1));
    1078                      if (is_numeric($boundary)) {
    1079                          $boundary = $boundary * $quiz->grade / 100.0;
    1080                      } else {
    1081                          return get_string('feedbackerrorboundaryformat', 'quiz', $i + 1);
    1082                      }
    1083                  }
    1084              }
    1085              if ($boundary <= 0 || $boundary >= $quiz->grade) {
    1086                  return get_string('feedbackerrorboundaryoutofrange', 'quiz', $i + 1);
    1087              }
    1088              if ($i > 0 && $boundary >= $quiz->feedbackboundaries[$i - 1]) {
    1089                  return get_string('feedbackerrororder', 'quiz', $i + 1);
    1090              }
    1091              $quiz->feedbackboundaries[$i] = $boundary;
    1092              $i += 1;
    1093          }
    1094          $numboundaries = $i;
    1095  
    1096          // Check there is nothing in the remaining unused fields.
    1097          if (!empty($quiz->feedbackboundaries)) {
    1098              for ($i = $numboundaries; $i < count($quiz->feedbackboundaries); $i += 1) {
    1099                  if (!empty($quiz->feedbackboundaries[$i]) &&
    1100                          trim($quiz->feedbackboundaries[$i]) != '') {
    1101                      return get_string('feedbackerrorjunkinboundary', 'quiz', $i + 1);
    1102                  }
    1103              }
    1104          }
    1105          for ($i = $numboundaries + 1; $i < count($quiz->feedbacktext); $i += 1) {
    1106              if (!empty($quiz->feedbacktext[$i]['text']) &&
    1107                      trim($quiz->feedbacktext[$i]['text']) != '') {
    1108                  return get_string('feedbackerrorjunkinfeedback', 'quiz', $i + 1);
    1109              }
    1110          }
    1111          // Needs to be bigger than $quiz->grade because of '<' test in quiz_feedback_for_grade().
    1112          $quiz->feedbackboundaries[-1] = $quiz->grade + 1;
    1113          $quiz->feedbackboundaries[$numboundaries] = 0;
    1114          $quiz->feedbackboundarycount = $numboundaries;
    1115      } else {
    1116          $quiz->feedbackboundarycount = -1;
    1117      }
    1118  
    1119      // Combing the individual settings into the review columns.
    1120      $quiz->reviewattempt = quiz_review_option_form_to_db($quiz, 'attempt');
    1121      $quiz->reviewcorrectness = quiz_review_option_form_to_db($quiz, 'correctness');
    1122      $quiz->reviewmarks = quiz_review_option_form_to_db($quiz, 'marks');
    1123      $quiz->reviewspecificfeedback = quiz_review_option_form_to_db($quiz, 'specificfeedback');
    1124      $quiz->reviewgeneralfeedback = quiz_review_option_form_to_db($quiz, 'generalfeedback');
    1125      $quiz->reviewrightanswer = quiz_review_option_form_to_db($quiz, 'rightanswer');
    1126      $quiz->reviewoverallfeedback = quiz_review_option_form_to_db($quiz, 'overallfeedback');
    1127      $quiz->reviewattempt |= mod_quiz_display_options::DURING;
    1128      $quiz->reviewoverallfeedback &= ~mod_quiz_display_options::DURING;
    1129  
    1130      // Ensure that disabled checkboxes in completion settings are set to 0.
    1131      if (empty($quiz->completionusegrade)) {
    1132          $quiz->completionpass = 0;
    1133      }
    1134      if (empty($quiz->completionpass)) {
    1135          $quiz->completionattemptsexhausted = 0;
    1136      }
    1137      if (empty($quiz->completionminattemptsenabled)) {
    1138          $quiz->completionminattempts = 0;
    1139      }
    1140  }
    1141  
    1142  /**
    1143   * Helper function for {@link quiz_process_options()}.
    1144   * @param object $fromform the sumbitted form date.
    1145   * @param string $field one of the review option field names.
    1146   */
    1147  function quiz_review_option_form_to_db($fromform, $field) {
    1148      static $times = array(
    1149          'during' => mod_quiz_display_options::DURING,
    1150          'immediately' => mod_quiz_display_options::IMMEDIATELY_AFTER,
    1151          'open' => mod_quiz_display_options::LATER_WHILE_OPEN,
    1152          'closed' => mod_quiz_display_options::AFTER_CLOSE,
    1153      );
    1154  
    1155      $review = 0;
    1156      foreach ($times as $whenname => $when) {
    1157          $fieldname = $field . $whenname;
    1158          if (!empty($fromform->$fieldname)) {
    1159              $review |= $when;
    1160              unset($fromform->$fieldname);
    1161          }
    1162      }
    1163  
    1164      return $review;
    1165  }
    1166  
    1167  /**
    1168   * This function is called at the end of quiz_add_instance
    1169   * and quiz_update_instance, to do the common processing.
    1170   *
    1171   * @param object $quiz the quiz object.
    1172   */
    1173  function quiz_after_add_or_update($quiz) {
    1174      global $DB;
    1175      $cmid = $quiz->coursemodule;
    1176  
    1177      // We need to use context now, so we need to make sure all needed info is already in db.
    1178      $DB->set_field('course_modules', 'instance', $quiz->id, array('id'=>$cmid));
    1179      $context = context_module::instance($cmid);
    1180  
    1181      // Save the feedback.
    1182      $DB->delete_records('quiz_feedback', array('quizid' => $quiz->id));
    1183  
    1184      for ($i = 0; $i <= $quiz->feedbackboundarycount; $i++) {
    1185          $feedback = new stdClass();
    1186          $feedback->quizid = $quiz->id;
    1187          $feedback->feedbacktext = $quiz->feedbacktext[$i]['text'];
    1188          $feedback->feedbacktextformat = $quiz->feedbacktext[$i]['format'];
    1189          $feedback->mingrade = $quiz->feedbackboundaries[$i];
    1190          $feedback->maxgrade = $quiz->feedbackboundaries[$i - 1];
    1191          $feedback->id = $DB->insert_record('quiz_feedback', $feedback);
    1192          $feedbacktext = file_save_draft_area_files((int)$quiz->feedbacktext[$i]['itemid'],
    1193                  $context->id, 'mod_quiz', 'feedback', $feedback->id,
    1194                  array('subdirs' => false, 'maxfiles' => -1, 'maxbytes' => 0),
    1195                  $quiz->feedbacktext[$i]['text']);
    1196          $DB->set_field('quiz_feedback', 'feedbacktext', $feedbacktext,
    1197                  array('id' => $feedback->id));
    1198      }
    1199  
    1200      // Store any settings belonging to the access rules.
    1201      quiz_access_manager::save_settings($quiz);
    1202  
    1203      // Update the events relating to this quiz.
    1204      quiz_update_events($quiz);
    1205      $completionexpected = (!empty($quiz->completionexpected)) ? $quiz->completionexpected : null;
    1206      \core_completion\api::update_completion_date_event($quiz->coursemodule, 'quiz', $quiz->id, $completionexpected);
    1207  
    1208      // Update related grade item.
    1209      quiz_grade_item_update($quiz);
    1210  }
    1211  
    1212  /**
    1213   * This function updates the events associated to the quiz.
    1214   * If $override is non-zero, then it updates only the events
    1215   * associated with the specified override.
    1216   *
    1217   * @uses QUIZ_MAX_EVENT_LENGTH
    1218   * @param object $quiz the quiz object.
    1219   * @param object optional $override limit to a specific override
    1220   */
    1221  function quiz_update_events($quiz, $override = null) {
    1222      global $DB;
    1223  
    1224      // Load the old events relating to this quiz.
    1225      $conds = array('modulename'=>'quiz',
    1226                     'instance'=>$quiz->id);
    1227      if (!empty($override)) {
    1228          // Only load events for this override.
    1229          if (isset($override->userid)) {
    1230              $conds['userid'] = $override->userid;
    1231          } else {
    1232              $conds['groupid'] = $override->groupid;
    1233          }
    1234      }
    1235      $oldevents = $DB->get_records('event', $conds, 'id ASC');
    1236  
    1237      // Now make a to-do list of all that needs to be updated.
    1238      if (empty($override)) {
    1239          // We are updating the primary settings for the quiz, so we need to add all the overrides.
    1240          $overrides = $DB->get_records('quiz_overrides', array('quiz' => $quiz->id), 'id ASC');
    1241          // It is necessary to add an empty stdClass to the beginning of the array as the $oldevents
    1242          // list contains the original (non-override) event for the module. If this is not included
    1243          // the logic below will end up updating the wrong row when we try to reconcile this $overrides
    1244          // list against the $oldevents list.
    1245          array_unshift($overrides, new stdClass());
    1246      } else {
    1247          // Just do the one override.
    1248          $overrides = array($override);
    1249      }
    1250  
    1251      // Get group override priorities.
    1252      $grouppriorities = quiz_get_group_override_priorities($quiz->id);
    1253  
    1254      foreach ($overrides as $current) {
    1255          $groupid   = isset($current->groupid)?  $current->groupid : 0;
    1256          $userid    = isset($current->userid)? $current->userid : 0;
    1257          $timeopen  = isset($current->timeopen)?  $current->timeopen : $quiz->timeopen;
    1258          $timeclose = isset($current->timeclose)? $current->timeclose : $quiz->timeclose;
    1259  
    1260          // Only add open/close events for an override if they differ from the quiz default.
    1261          $addopen  = empty($current->id) || !empty($current->timeopen);
    1262          $addclose = empty($current->id) || !empty($current->timeclose);
    1263  
    1264          if (!empty($quiz->coursemodule)) {
    1265              $cmid = $quiz->coursemodule;
    1266          } else {
    1267              $cmid = get_coursemodule_from_instance('quiz', $quiz->id, $quiz->course)->id;
    1268          }
    1269  
    1270          $event = new stdClass();
    1271          $event->type = !$timeclose ? CALENDAR_EVENT_TYPE_ACTION : CALENDAR_EVENT_TYPE_STANDARD;
    1272          $event->description = format_module_intro('quiz', $quiz, $cmid, false);
    1273          $event->format = FORMAT_HTML;
    1274          // Events module won't show user events when the courseid is nonzero.
    1275          $event->courseid    = ($userid) ? 0 : $quiz->course;
    1276          $event->groupid     = $groupid;
    1277          $event->userid      = $userid;
    1278          $event->modulename  = 'quiz';
    1279          $event->instance    = $quiz->id;
    1280          $event->timestart   = $timeopen;
    1281          $event->timeduration = max($timeclose - $timeopen, 0);
    1282          $event->timesort    = $timeopen;
    1283          $event->visible     = instance_is_visible('quiz', $quiz);
    1284          $event->eventtype   = QUIZ_EVENT_TYPE_OPEN;
    1285          $event->priority    = null;
    1286  
    1287          // Determine the event name and priority.
    1288          if ($groupid) {
    1289              // Group override event.
    1290              $params = new stdClass();
    1291              $params->quiz = $quiz->name;
    1292              $params->group = groups_get_group_name($groupid);
    1293              if ($params->group === false) {
    1294                  // Group doesn't exist, just skip it.
    1295                  continue;
    1296              }
    1297              $eventname = get_string('overridegroupeventname', 'quiz', $params);
    1298              // Set group override priority.
    1299              if ($grouppriorities !== null) {
    1300                  $openpriorities = $grouppriorities['open'];
    1301                  if (isset($openpriorities[$timeopen])) {
    1302                      $event->priority = $openpriorities[$timeopen];
    1303                  }
    1304              }
    1305          } else if ($userid) {
    1306              // User override event.
    1307              $params = new stdClass();
    1308              $params->quiz = $quiz->name;
    1309              $eventname = get_string('overrideusereventname', 'quiz', $params);
    1310              // Set user override priority.
    1311              $event->priority = CALENDAR_EVENT_USER_OVERRIDE_PRIORITY;
    1312          } else {
    1313              // The parent event.
    1314              $eventname = $quiz->name;
    1315          }
    1316  
    1317          if ($addopen or $addclose) {
    1318              // Separate start and end events.
    1319              $event->timeduration  = 0;
    1320              if ($timeopen && $addopen) {
    1321                  if ($oldevent = array_shift($oldevents)) {
    1322                      $event->id = $oldevent->id;
    1323                  } else {
    1324                      unset($event->id);
    1325                  }
    1326                  $event->name = get_string('quizeventopens', 'quiz', $eventname);
    1327                  // The method calendar_event::create will reuse a db record if the id field is set.
    1328                  calendar_event::create($event, false);
    1329              }
    1330              if ($timeclose && $addclose) {
    1331                  if ($oldevent = array_shift($oldevents)) {
    1332                      $event->id = $oldevent->id;
    1333                  } else {
    1334                      unset($event->id);
    1335                  }
    1336                  $event->type      = CALENDAR_EVENT_TYPE_ACTION;
    1337                  $event->name      = get_string('quizeventcloses', 'quiz', $eventname);
    1338                  $event->timestart = $timeclose;
    1339                  $event->timesort  = $timeclose;
    1340                  $event->eventtype = QUIZ_EVENT_TYPE_CLOSE;
    1341                  if ($groupid && $grouppriorities !== null) {
    1342                      $closepriorities = $grouppriorities['close'];
    1343                      if (isset($closepriorities[$timeclose])) {
    1344                          $event->priority = $closepriorities[$timeclose];
    1345                      }
    1346                  }
    1347                  calendar_event::create($event, false);
    1348              }
    1349          }
    1350      }
    1351  
    1352      // Delete any leftover events.
    1353      foreach ($oldevents as $badevent) {
    1354          $badevent = calendar_event::load($badevent);
    1355          $badevent->delete();
    1356      }
    1357  }
    1358  
    1359  /**
    1360   * Calculates the priorities of timeopen and timeclose values for group overrides for a quiz.
    1361   *
    1362   * @param int $quizid The quiz ID.
    1363   * @return array|null Array of group override priorities for open and close times. Null if there are no group overrides.
    1364   */
    1365  function quiz_get_group_override_priorities($quizid) {
    1366      global $DB;
    1367  
    1368      // Fetch group overrides.
    1369      $where = 'quiz = :quiz AND groupid IS NOT NULL';
    1370      $params = ['quiz' => $quizid];
    1371      $overrides = $DB->get_records_select('quiz_overrides', $where, $params, '', 'id, timeopen, timeclose');
    1372      if (!$overrides) {
    1373          return null;
    1374      }
    1375  
    1376      $grouptimeopen = [];
    1377      $grouptimeclose = [];
    1378      foreach ($overrides as $override) {
    1379          if ($override->timeopen !== null && !in_array($override->timeopen, $grouptimeopen)) {
    1380              $grouptimeopen[] = $override->timeopen;
    1381          }
    1382          if ($override->timeclose !== null && !in_array($override->timeclose, $grouptimeclose)) {
    1383              $grouptimeclose[] = $override->timeclose;
    1384          }
    1385      }
    1386  
    1387      // Sort open times in ascending manner. The earlier open time gets higher priority.
    1388      sort($grouptimeopen);
    1389      // Set priorities.
    1390      $opengrouppriorities = [];
    1391      $openpriority = 1;
    1392      foreach ($grouptimeopen as $timeopen) {
    1393          $opengrouppriorities[$timeopen] = $openpriority++;
    1394      }
    1395  
    1396      // Sort close times in descending manner. The later close time gets higher priority.
    1397      rsort($grouptimeclose);
    1398      // Set priorities.
    1399      $closegrouppriorities = [];
    1400      $closepriority = 1;
    1401      foreach ($grouptimeclose as $timeclose) {
    1402          $closegrouppriorities[$timeclose] = $closepriority++;
    1403      }
    1404  
    1405      return [
    1406          'open' => $opengrouppriorities,
    1407          'close' => $closegrouppriorities
    1408      ];
    1409  }
    1410  
    1411  /**
    1412   * List the actions that correspond to a view of this module.
    1413   * This is used by the participation report.
    1414   *
    1415   * Note: This is not used by new logging system. Event with
    1416   *       crud = 'r' and edulevel = LEVEL_PARTICIPATING will
    1417   *       be considered as view action.
    1418   *
    1419   * @return array
    1420   */
    1421  function quiz_get_view_actions() {
    1422      return array('view', 'view all', 'report', 'review');
    1423  }
    1424  
    1425  /**
    1426   * List the actions that correspond to a post of this module.
    1427   * This is used by the participation report.
    1428   *
    1429   * Note: This is not used by new logging system. Event with
    1430   *       crud = ('c' || 'u' || 'd') and edulevel = LEVEL_PARTICIPATING
    1431   *       will be considered as post action.
    1432   *
    1433   * @return array
    1434   */
    1435  function quiz_get_post_actions() {
    1436      return array('attempt', 'close attempt', 'preview', 'editquestions',
    1437              'delete attempt', 'manualgrade');
    1438  }
    1439  
    1440  /**
    1441   * @param array $questionids of question ids.
    1442   * @return bool whether any of these questions are used by any instance of this module.
    1443   */
    1444  function quiz_questions_in_use($questionids) {
    1445      global $DB, $CFG;
    1446      require_once($CFG->libdir . '/questionlib.php');
    1447      list($test, $params) = $DB->get_in_or_equal($questionids);
    1448      return $DB->record_exists_select('quiz_slots',
    1449              'questionid ' . $test, $params) || question_engine::questions_in_use(
    1450              $questionids, new qubaid_join('{quiz_attempts} quiza',
    1451              'quiza.uniqueid', 'quiza.preview = 0'));
    1452  }
    1453  
    1454  /**
    1455   * Implementation of the function for printing the form elements that control
    1456   * whether the course reset functionality affects the quiz.
    1457   *
    1458   * @param $mform the course reset form that is being built.
    1459   */
    1460  function quiz_reset_course_form_definition($mform) {
    1461      $mform->addElement('header', 'quizheader', get_string('modulenameplural', 'quiz'));
    1462      $mform->addElement('advcheckbox', 'reset_quiz_attempts',
    1463              get_string('removeallquizattempts', 'quiz'));
    1464      $mform->addElement('advcheckbox', 'reset_quiz_user_overrides',
    1465              get_string('removealluseroverrides', 'quiz'));
    1466      $mform->addElement('advcheckbox', 'reset_quiz_group_overrides',
    1467              get_string('removeallgroupoverrides', 'quiz'));
    1468  }
    1469  
    1470  /**
    1471   * Course reset form defaults.
    1472   * @return array the defaults.
    1473   */
    1474  function quiz_reset_course_form_defaults($course) {
    1475      return array('reset_quiz_attempts' => 1,
    1476                   'reset_quiz_group_overrides' => 1,
    1477                   'reset_quiz_user_overrides' => 1);
    1478  }
    1479  
    1480  /**
    1481   * Removes all grades from gradebook
    1482   *
    1483   * @param int $courseid
    1484   * @param string optional type
    1485   */
    1486  function quiz_reset_gradebook($courseid, $type='') {
    1487      global $CFG, $DB;
    1488  
    1489      $quizzes = $DB->get_records_sql("
    1490              SELECT q.*, cm.idnumber as cmidnumber, q.course as courseid
    1491              FROM {modules} m
    1492              JOIN {course_modules} cm ON m.id = cm.module
    1493              JOIN {quiz} q ON cm.instance = q.id
    1494              WHERE m.name = 'quiz' AND cm.course = ?", array($courseid));
    1495  
    1496      foreach ($quizzes as $quiz) {
    1497          quiz_grade_item_update($quiz, 'reset');
    1498      }
    1499  }
    1500  
    1501  /**
    1502   * Actual implementation of the reset course functionality, delete all the
    1503   * quiz attempts for course $data->courseid, if $data->reset_quiz_attempts is
    1504   * set and true.
    1505   *
    1506   * Also, move the quiz open and close dates, if the course start date is changing.
    1507   *
    1508   * @param object $data the data submitted from the reset course.
    1509   * @return array status array
    1510   */
    1511  function quiz_reset_userdata($data) {
    1512      global $CFG, $DB;
    1513      require_once($CFG->libdir . '/questionlib.php');
    1514  
    1515      $componentstr = get_string('modulenameplural', 'quiz');
    1516      $status = array();
    1517  
    1518      // Delete attempts.
    1519      if (!empty($data->reset_quiz_attempts)) {
    1520          question_engine::delete_questions_usage_by_activities(new qubaid_join(
    1521                  '{quiz_attempts} quiza JOIN {quiz} quiz ON quiza.quiz = quiz.id',
    1522                  'quiza.uniqueid', 'quiz.course = :quizcourseid',
    1523                  array('quizcourseid' => $data->courseid)));
    1524  
    1525          $DB->delete_records_select('quiz_attempts',
    1526                  'quiz IN (SELECT id FROM {quiz} WHERE course = ?)', array($data->courseid));
    1527          $status[] = array(
    1528              'component' => $componentstr,
    1529              'item' => get_string('attemptsdeleted', 'quiz'),
    1530              'error' => false);
    1531  
    1532          // Remove all grades from gradebook.
    1533          $DB->delete_records_select('quiz_grades',
    1534                  'quiz IN (SELECT id FROM {quiz} WHERE course = ?)', array($data->courseid));
    1535          if (empty($data->reset_gradebook_grades)) {
    1536              quiz_reset_gradebook($data->courseid);
    1537          }
    1538          $status[] = array(
    1539              'component' => $componentstr,
    1540              'item' => get_string('gradesdeleted', 'quiz'),
    1541              'error' => false);
    1542      }
    1543  
    1544      $purgeoverrides = false;
    1545  
    1546      // Remove user overrides.
    1547      if (!empty($data->reset_quiz_user_overrides)) {
    1548          $DB->delete_records_select('quiz_overrides',
    1549                  'quiz IN (SELECT id FROM {quiz} WHERE course = ?) AND userid IS NOT NULL', array($data->courseid));
    1550          $status[] = array(
    1551              'component' => $componentstr,
    1552              'item' => get_string('useroverridesdeleted', 'quiz'),
    1553              'error' => false);
    1554          $purgeoverrides = true;
    1555      }
    1556      // Remove group overrides.
    1557      if (!empty($data->reset_quiz_group_overrides)) {
    1558          $DB->delete_records_select('quiz_overrides',
    1559                  'quiz IN (SELECT id FROM {quiz} WHERE course = ?) AND groupid IS NOT NULL', array($data->courseid));
    1560          $status[] = array(
    1561              'component' => $componentstr,
    1562              'item' => get_string('groupoverridesdeleted', 'quiz'),
    1563              'error' => false);
    1564          $purgeoverrides = true;
    1565      }
    1566  
    1567      // Updating dates - shift may be negative too.
    1568      if ($data->timeshift) {
    1569          $DB->execute("UPDATE {quiz_overrides}
    1570                           SET timeopen = timeopen + ?
    1571                         WHERE quiz IN (SELECT id FROM {quiz} WHERE course = ?)
    1572                           AND timeopen <> 0", array($data->timeshift, $data->courseid));
    1573          $DB->execute("UPDATE {quiz_overrides}
    1574                           SET timeclose = timeclose + ?
    1575                         WHERE quiz IN (SELECT id FROM {quiz} WHERE course = ?)
    1576                           AND timeclose <> 0", array($data->timeshift, $data->courseid));
    1577  
    1578          $purgeoverrides = true;
    1579  
    1580          // Any changes to the list of dates that needs to be rolled should be same during course restore and course reset.
    1581          // See MDL-9367.
    1582          shift_course_mod_dates('quiz', array('timeopen', 'timeclose'),
    1583                  $data->timeshift, $data->courseid);
    1584  
    1585          $status[] = array(
    1586              'component' => $componentstr,
    1587              'item' => get_string('openclosedatesupdated', 'quiz'),
    1588              'error' => false);
    1589      }
    1590  
    1591      if ($purgeoverrides) {
    1592          cache::make('mod_quiz', 'overrides')->purge();
    1593      }
    1594  
    1595      return $status;
    1596  }
    1597  
    1598  /**
    1599   * @deprecated since Moodle 3.3, when the block_course_overview block was removed.
    1600   */
    1601  function quiz_print_overview() {
    1602      throw new coding_exception('quiz_print_overview() can not be used any more and is obsolete.');
    1603  }
    1604  
    1605  /**
    1606   * Return a textual summary of the number of attempts that have been made at a particular quiz,
    1607   * returns '' if no attempts have been made yet, unless $returnzero is passed as true.
    1608   *
    1609   * @param object $quiz the quiz object. Only $quiz->id is used at the moment.
    1610   * @param object $cm the cm object. Only $cm->course, $cm->groupmode and
    1611   *      $cm->groupingid fields are used at the moment.
    1612   * @param bool $returnzero if false (default), when no attempts have been
    1613   *      made '' is returned instead of 'Attempts: 0'.
    1614   * @param int $currentgroup if there is a concept of current group where this method is being called
    1615   *         (e.g. a report) pass it in here. Default 0 which means no current group.
    1616   * @return string a string like "Attempts: 123", "Attemtps 123 (45 from your groups)" or
    1617   *          "Attemtps 123 (45 from this group)".
    1618   */
    1619  function quiz_num_attempt_summary($quiz, $cm, $returnzero = false, $currentgroup = 0) {
    1620      global $DB, $USER;
    1621      $numattempts = $DB->count_records('quiz_attempts', array('quiz'=> $quiz->id, 'preview'=>0));
    1622      if ($numattempts || $returnzero) {
    1623          if (groups_get_activity_groupmode($cm)) {
    1624              $a = new stdClass();
    1625              $a->total = $numattempts;
    1626              if ($currentgroup) {
    1627                  $a->group = $DB->count_records_sql('SELECT COUNT(DISTINCT qa.id) FROM ' .
    1628                          '{quiz_attempts} qa JOIN ' .
    1629                          '{groups_members} gm ON qa.userid = gm.userid ' .
    1630                          'WHERE quiz = ? AND preview = 0 AND groupid = ?',
    1631                          array($quiz->id, $currentgroup));
    1632                  return get_string('attemptsnumthisgroup', 'quiz', $a);
    1633              } else if ($groups = groups_get_all_groups($cm->course, $USER->id, $cm->groupingid)) {
    1634                  list($usql, $params) = $DB->get_in_or_equal(array_keys($groups));
    1635                  $a->group = $DB->count_records_sql('SELECT COUNT(DISTINCT qa.id) FROM ' .
    1636                          '{quiz_attempts} qa JOIN ' .
    1637                          '{groups_members} gm ON qa.userid = gm.userid ' .
    1638                          'WHERE quiz = ? AND preview = 0 AND ' .
    1639                          "groupid $usql", array_merge(array($quiz->id), $params));
    1640                  return get_string('attemptsnumyourgroups', 'quiz', $a);
    1641              }
    1642          }
    1643          return get_string('attemptsnum', 'quiz', $numattempts);
    1644      }
    1645      return '';
    1646  }
    1647  
    1648  /**
    1649   * Returns the same as {@link quiz_num_attempt_summary()} but wrapped in a link
    1650   * to the quiz reports.
    1651   *
    1652   * @param object $quiz the quiz object. Only $quiz->id is used at the moment.
    1653   * @param object $cm the cm object. Only $cm->course, $cm->groupmode and
    1654   *      $cm->groupingid fields are used at the moment.
    1655   * @param object $context the quiz context.
    1656   * @param bool $returnzero if false (default), when no attempts have been made
    1657   *      '' is returned instead of 'Attempts: 0'.
    1658   * @param int $currentgroup if there is a concept of current group where this method is being called
    1659   *         (e.g. a report) pass it in here. Default 0 which means no current group.
    1660   * @return string HTML fragment for the link.
    1661   */
    1662  function quiz_attempt_summary_link_to_reports($quiz, $cm, $context, $returnzero = false,
    1663          $currentgroup = 0) {
    1664      global $PAGE;
    1665  
    1666      return $PAGE->get_renderer('mod_quiz')->quiz_attempt_summary_link_to_reports(
    1667              $quiz, $cm, $context, $returnzero, $currentgroup);
    1668  }
    1669  
    1670  /**
    1671   * @param string $feature FEATURE_xx constant for requested feature
    1672   * @return bool True if quiz supports feature
    1673   */
    1674  function quiz_supports($feature) {
    1675      switch($feature) {
    1676          case FEATURE_GROUPS:                    return true;
    1677          case FEATURE_GROUPINGS:                 return true;
    1678          case FEATURE_MOD_INTRO:                 return true;
    1679          case FEATURE_COMPLETION_TRACKS_VIEWS:   return true;
    1680          case FEATURE_COMPLETION_HAS_RULES:      return true;
    1681          case FEATURE_GRADE_HAS_GRADE:           return true;
    1682          case FEATURE_GRADE_OUTCOMES:            return true;
    1683          case FEATURE_BACKUP_MOODLE2:            return true;
    1684          case FEATURE_SHOW_DESCRIPTION:          return true;
    1685          case FEATURE_CONTROLS_GRADE_VISIBILITY: return true;
    1686          case FEATURE_USES_QUESTIONS:            return true;
    1687          case FEATURE_PLAGIARISM:                return true;
    1688  
    1689          default: return null;
    1690      }
    1691  }
    1692  
    1693  /**
    1694   * @return array all other caps used in module
    1695   */
    1696  function quiz_get_extra_capabilities() {
    1697      global $CFG;
    1698      require_once($CFG->libdir . '/questionlib.php');
    1699      return question_get_all_capabilities();
    1700  }
    1701  
    1702  /**
    1703   * This function extends the settings navigation block for the site.
    1704   *
    1705   * It is safe to rely on PAGE here as we will only ever be within the module
    1706   * context when this is called
    1707   *
    1708   * @param settings_navigation $settings
    1709   * @param navigation_node $quiznode
    1710   * @return void
    1711   */
    1712  function quiz_extend_settings_navigation($settings, $quiznode) {
    1713      global $PAGE, $CFG;
    1714  
    1715      // Require {@link questionlib.php}
    1716      // Included here as we only ever want to include this file if we really need to.
    1717      require_once($CFG->libdir . '/questionlib.php');
    1718  
    1719      // We want to add these new nodes after the Edit settings node, and before the
    1720      // Locally assigned roles node. Of course, both of those are controlled by capabilities.
    1721      $keys = $quiznode->get_children_key_list();
    1722      $beforekey = null;
    1723      $i = array_search('modedit', $keys);
    1724      if ($i === false and array_key_exists(0, $keys)) {
    1725          $beforekey = $keys[0];
    1726      } else if (array_key_exists($i + 1, $keys)) {
    1727          $beforekey = $keys[$i + 1];
    1728      }
    1729  
    1730      if (has_any_capability(['mod/quiz:manageoverrides', 'mod/quiz:viewoverrides'], $PAGE->cm->context)) {
    1731          $url = new moodle_url('/mod/quiz/overrides.php', array('cmid'=>$PAGE->cm->id));
    1732          $node = navigation_node::create(get_string('groupoverrides', 'quiz'),
    1733                  new moodle_url($url, array('mode'=>'group')),
    1734                  navigation_node::TYPE_SETTING, null, 'mod_quiz_groupoverrides');
    1735          $quiznode->add_node($node, $beforekey);
    1736  
    1737          $node = navigation_node::create(get_string('useroverrides', 'quiz'),
    1738                  new moodle_url($url, array('mode'=>'user')),
    1739                  navigation_node::TYPE_SETTING, null, 'mod_quiz_useroverrides');
    1740          $quiznode->add_node($node, $beforekey);
    1741      }
    1742  
    1743      if (has_capability('mod/quiz:manage', $PAGE->cm->context)) {
    1744          $node = navigation_node::create(get_string('editquiz', 'quiz'),
    1745                  new moodle_url('/mod/quiz/edit.php', array('cmid'=>$PAGE->cm->id)),
    1746                  navigation_node::TYPE_SETTING, null, 'mod_quiz_edit',
    1747                  new pix_icon('t/edit', ''));
    1748          $quiznode->add_node($node, $beforekey);
    1749      }
    1750  
    1751      if (has_capability('mod/quiz:preview', $PAGE->cm->context)) {
    1752          $url = new moodle_url('/mod/quiz/startattempt.php',
    1753                  array('cmid'=>$PAGE->cm->id, 'sesskey'=>sesskey()));
    1754          $node = navigation_node::create(get_string('preview', 'quiz'), $url,
    1755                  navigation_node::TYPE_SETTING, null, 'mod_quiz_preview',
    1756                  new pix_icon('i/preview', ''));
    1757          $quiznode->add_node($node, $beforekey);
    1758      }
    1759  
    1760      if (has_any_capability(array('mod/quiz:viewreports', 'mod/quiz:grade'), $PAGE->cm->context)) {
    1761          require_once($CFG->dirroot . '/mod/quiz/report/reportlib.php');
    1762          $reportlist = quiz_report_list($PAGE->cm->context);
    1763  
    1764          $url = new moodle_url('/mod/quiz/report.php',
    1765                  array('id' => $PAGE->cm->id, 'mode' => reset($reportlist)));
    1766          $reportnode = $quiznode->add_node(navigation_node::create(get_string('results', 'quiz'), $url,
    1767                  navigation_node::TYPE_SETTING,
    1768                  null, null, new pix_icon('i/report', '')), $beforekey);
    1769  
    1770          foreach ($reportlist as $report) {
    1771              $url = new moodle_url('/mod/quiz/report.php',
    1772                      array('id' => $PAGE->cm->id, 'mode' => $report));
    1773              $reportnode->add_node(navigation_node::create(get_string($report, 'quiz_'.$report), $url,
    1774                      navigation_node::TYPE_SETTING,
    1775                      null, 'quiz_report_' . $report, new pix_icon('i/item', '')));
    1776          }
    1777      }
    1778  
    1779      question_extend_settings_navigation($quiznode, $PAGE->cm->context)->trim_if_empty();
    1780  }
    1781  
    1782  /**
    1783   * Serves the quiz files.
    1784   *
    1785   * @package  mod_quiz
    1786   * @category files
    1787   * @param stdClass $course course object
    1788   * @param stdClass $cm course module object
    1789   * @param stdClass $context context object
    1790   * @param string $filearea file area
    1791   * @param array $args extra arguments
    1792   * @param bool $forcedownload whether or not force download
    1793   * @param array $options additional options affecting the file serving
    1794   * @return bool false if file not found, does not return if found - justsend the file
    1795   */
    1796  function quiz_pluginfile($course, $cm, $context, $filearea, $args, $forcedownload, array $options=array()) {
    1797      global $CFG, $DB;
    1798  
    1799      if ($context->contextlevel != CONTEXT_MODULE) {
    1800          return false;
    1801      }
    1802  
    1803      require_login($course, false, $cm);
    1804  
    1805      if (!$quiz = $DB->get_record('quiz', array('id'=>$cm->instance))) {
    1806          return false;
    1807      }
    1808  
    1809      // The 'intro' area is served by pluginfile.php.
    1810      $fileareas = array('feedback');
    1811      if (!in_array($filearea, $fileareas)) {
    1812          return false;
    1813      }
    1814  
    1815      $feedbackid = (int)array_shift($args);
    1816      if (!$feedback = $DB->get_record('quiz_feedback', array('id'=>$feedbackid))) {
    1817          return false;
    1818      }
    1819  
    1820      $fs = get_file_storage();
    1821      $relativepath = implode('/', $args);
    1822      $fullpath = "/$context->id/mod_quiz/$filearea/$feedbackid/$relativepath";
    1823      if (!$file = $fs->get_file_by_hash(sha1($fullpath)) or $file->is_directory()) {
    1824          return false;
    1825      }
    1826      send_stored_file($file, 0, 0, true, $options);
    1827  }
    1828  
    1829  /**
    1830   * Called via pluginfile.php -> question_pluginfile to serve files belonging to
    1831   * a question in a question_attempt when that attempt is a quiz attempt.
    1832   *
    1833   * @package  mod_quiz
    1834   * @category files
    1835   * @param stdClass $course course settings object
    1836   * @param stdClass $context context object
    1837   * @param string $component the name of the component we are serving files for.
    1838   * @param string $filearea the name of the file area.
    1839   * @param int $qubaid the attempt usage id.
    1840   * @param int $slot the id of a question in this quiz attempt.
    1841   * @param array $args the remaining bits of the file path.
    1842   * @param bool $forcedownload whether the user must be forced to download the file.
    1843   * @param array $options additional options affecting the file serving
    1844   * @return bool false if file not found, does not return if found - justsend the file
    1845   */
    1846  function quiz_question_pluginfile($course, $context, $component,
    1847          $filearea, $qubaid, $slot, $args, $forcedownload, array $options=array()) {
    1848      global $CFG;
    1849      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
    1850  
    1851      $attemptobj = quiz_attempt::create_from_usage_id($qubaid);
    1852      require_login($attemptobj->get_course(), false, $attemptobj->get_cm());
    1853  
    1854      if ($attemptobj->is_own_attempt() && !$attemptobj->is_finished()) {
    1855          // In the middle of an attempt.
    1856          if (!$attemptobj->is_preview_user()) {
    1857              $attemptobj->require_capability('mod/quiz:attempt');
    1858          }
    1859          $isreviewing = false;
    1860  
    1861      } else {
    1862          // Reviewing an attempt.
    1863          $attemptobj->check_review_capability();
    1864          $isreviewing = true;
    1865      }
    1866  
    1867      if (!$attemptobj->check_file_access($slot, $isreviewing, $context->id,
    1868              $component, $filearea, $args, $forcedownload)) {
    1869          send_file_not_found();
    1870      }
    1871  
    1872      $fs = get_file_storage();
    1873      $relativepath = implode('/', $args);
    1874      $fullpath = "/$context->id/$component/$filearea/$relativepath";
    1875      if (!$file = $fs->get_file_by_hash(sha1($fullpath)) or $file->is_directory()) {
    1876          send_file_not_found();
    1877      }
    1878  
    1879      send_stored_file($file, 0, 0, $forcedownload, $options);
    1880  }
    1881  
    1882  /**
    1883   * Return a list of page types
    1884   * @param string $pagetype current page type
    1885   * @param stdClass $parentcontext Block's parent context
    1886   * @param stdClass $currentcontext Current context of block
    1887   */
    1888  function quiz_page_type_list($pagetype, $parentcontext, $currentcontext) {
    1889      $module_pagetype = array(
    1890          'mod-quiz-*'       => get_string('page-mod-quiz-x', 'quiz'),
    1891          'mod-quiz-view'    => get_string('page-mod-quiz-view', 'quiz'),
    1892          'mod-quiz-attempt' => get_string('page-mod-quiz-attempt', 'quiz'),
    1893          'mod-quiz-summary' => get_string('page-mod-quiz-summary', 'quiz'),
    1894          'mod-quiz-review'  => get_string('page-mod-quiz-review', 'quiz'),
    1895          'mod-quiz-edit'    => get_string('page-mod-quiz-edit', 'quiz'),
    1896          'mod-quiz-report'  => get_string('page-mod-quiz-report', 'quiz'),
    1897      );
    1898      return $module_pagetype;
    1899  }
    1900  
    1901  /**
    1902   * @return the options for quiz navigation.
    1903   */
    1904  function quiz_get_navigation_options() {
    1905      return array(
    1906          QUIZ_NAVMETHOD_FREE => get_string('navmethod_free', 'quiz'),
    1907          QUIZ_NAVMETHOD_SEQ  => get_string('navmethod_seq', 'quiz')
    1908      );
    1909  }
    1910  
    1911  /**
    1912   * Check if the module has any update that affects the current user since a given time.
    1913   *
    1914   * @param  cm_info $cm course module data
    1915   * @param  int $from the time to check updates from
    1916   * @param  array $filter  if we need to check only specific updates
    1917   * @return stdClass an object with the different type of areas indicating if they were updated or not
    1918   * @since Moodle 3.2
    1919   */
    1920  function quiz_check_updates_since(cm_info $cm, $from, $filter = array()) {
    1921      global $DB, $USER, $CFG;
    1922      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
    1923  
    1924      $updates = course_check_module_updates_since($cm, $from, array(), $filter);
    1925  
    1926      // Check if questions were updated.
    1927      $updates->questions = (object) array('updated' => false);
    1928      $quizobj = quiz::create($cm->instance, $USER->id);
    1929      $quizobj->preload_questions();
    1930      $quizobj->load_questions();
    1931      $questionids = array_keys($quizobj->get_questions());
    1932      if (!empty($questionids)) {
    1933          list($questionsql, $params) = $DB->get_in_or_equal($questionids, SQL_PARAMS_NAMED);
    1934          $select = 'id ' . $questionsql . ' AND (timemodified > :time1 OR timecreated > :time2)';
    1935          $params['time1'] = $from;
    1936          $params['time2'] = $from;
    1937          $questions = $DB->get_records_select('question', $select, $params, '', 'id');
    1938          if (!empty($questions)) {
    1939              $updates->questions->updated = true;
    1940              $updates->questions->itemids = array_keys($questions);
    1941          }
    1942      }
    1943  
    1944      // Check for new attempts or grades.
    1945      $updates->attempts = (object) array('updated' => false);
    1946      $updates->grades = (object) array('updated' => false);
    1947      $select = 'quiz = ? AND userid = ? AND timemodified > ?';
    1948      $params = array($cm->instance, $USER->id, $from);
    1949  
    1950      $attempts = $DB->get_records_select('quiz_attempts', $select, $params, '', 'id');
    1951      if (!empty($attempts)) {
    1952          $updates->attempts->updated = true;
    1953          $updates->attempts->itemids = array_keys($attempts);
    1954      }
    1955      $grades = $DB->get_records_select('quiz_grades', $select, $params, '', 'id');
    1956      if (!empty($grades)) {
    1957          $updates->grades->updated = true;
    1958          $updates->grades->itemids = array_keys($grades);
    1959      }
    1960  
    1961      // Now, teachers should see other students updates.
    1962      if (has_capability('mod/quiz:viewreports', $cm->context)) {
    1963          $select = 'quiz = ? AND timemodified > ?';
    1964          $params = array($cm->instance, $from);
    1965  
    1966          if (groups_get_activity_groupmode($cm) == SEPARATEGROUPS) {
    1967              $groupusers = array_keys(groups_get_activity_shared_group_members($cm));
    1968              if (empty($groupusers)) {
    1969                  return $updates;
    1970              }
    1971              list($insql, $inparams) = $DB->get_in_or_equal($groupusers);
    1972              $select .= ' AND userid ' . $insql;
    1973              $params = array_merge($params, $inparams);
    1974          }
    1975  
    1976          $updates->userattempts = (object) array('updated' => false);
    1977          $attempts = $DB->get_records_select('quiz_attempts', $select, $params, '', 'id');
    1978          if (!empty($attempts)) {
    1979              $updates->userattempts->updated = true;
    1980              $updates->userattempts->itemids = array_keys($attempts);
    1981          }
    1982  
    1983          $updates->usergrades = (object) array('updated' => false);
    1984          $grades = $DB->get_records_select('quiz_grades', $select, $params, '', 'id');
    1985          if (!empty($grades)) {
    1986              $updates->usergrades->updated = true;
    1987              $updates->usergrades->itemids = array_keys($grades);
    1988          }
    1989      }
    1990      return $updates;
    1991  }
    1992  
    1993  /**
    1994   * Get icon mapping for font-awesome.
    1995   */
    1996  function mod_quiz_get_fontawesome_icon_map() {
    1997      return [
    1998          'mod_quiz:navflagged' => 'fa-flag',
    1999      ];
    2000  }
    2001  
    2002  /**
    2003   * This function receives a calendar event and returns the action associated with it, or null if there is none.
    2004   *
    2005   * This is used by block_myoverview in order to display the event appropriately. If null is returned then the event
    2006   * is not displayed on the block.
    2007   *
    2008   * @param calendar_event $event
    2009   * @param \core_calendar\action_factory $factory
    2010   * @param int $userid User id to use for all capability checks, etc. Set to 0 for current user (default).
    2011   * @return \core_calendar\local\event\entities\action_interface|null
    2012   */
    2013  function mod_quiz_core_calendar_provide_event_action(calendar_event $event,
    2014                                                       \core_calendar\action_factory $factory,
    2015                                                       int $userid = 0) {
    2016      global $CFG, $USER;
    2017  
    2018      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
    2019  
    2020      if (empty($userid)) {
    2021          $userid = $USER->id;
    2022      }
    2023  
    2024      $cm = get_fast_modinfo($event->courseid, $userid)->instances['quiz'][$event->instance];
    2025      $quizobj = quiz::create($cm->instance, $userid);
    2026      $quiz = $quizobj->get_quiz();
    2027  
    2028      // Check they have capabilities allowing them to view the quiz.
    2029      if (!has_any_capability(['mod/quiz:reviewmyattempts', 'mod/quiz:attempt'], $quizobj->get_context(), $userid)) {
    2030          return null;
    2031      }
    2032  
    2033      $completion = new \completion_info($cm->get_course());
    2034  
    2035      $completiondata = $completion->get_data($cm, false, $userid);
    2036  
    2037      if ($completiondata->completionstate != COMPLETION_INCOMPLETE) {
    2038          return null;
    2039      }
    2040  
    2041      quiz_update_effective_access($quiz, $userid);
    2042  
    2043      // Check if quiz is closed, if so don't display it.
    2044      if (!empty($quiz->timeclose) && $quiz->timeclose <= time()) {
    2045          return null;
    2046      }
    2047  
    2048      if (!$quizobj->is_participant($userid)) {
    2049          // If the user is not a participant then they have
    2050          // no action to take. This will filter out the events for teachers.
    2051          return null;
    2052      }
    2053  
    2054      $attempts = quiz_get_user_attempts($quizobj->get_quizid(), $userid);
    2055      if (!empty($attempts)) {
    2056          // The student's last attempt is finished.
    2057          return null;
    2058      }
    2059  
    2060      $name = get_string('attemptquiznow', 'quiz');
    2061      $url = new \moodle_url('/mod/quiz/view.php', [
    2062          'id' => $cm->id
    2063      ]);
    2064      $itemcount = 1;
    2065      $actionable = true;
    2066  
    2067      // Check if the quiz is not currently actionable.
    2068      if (!empty($quiz->timeopen) && $quiz->timeopen > time()) {
    2069          $actionable = false;
    2070      }
    2071  
    2072      return $factory->create_instance(
    2073          $name,
    2074          $url,
    2075          $itemcount,
    2076          $actionable
    2077      );
    2078  }
    2079  
    2080  /**
    2081   * Add a get_coursemodule_info function in case any quiz type wants to add 'extra' information
    2082   * for the course (see resource).
    2083   *
    2084   * Given a course_module object, this function returns any "extra" information that may be needed
    2085   * when printing this activity in a course listing.  See get_array_of_activities() in course/lib.php.
    2086   *
    2087   * @param stdClass $coursemodule The coursemodule object (record).
    2088   * @return cached_cm_info An object on information that the courses
    2089   *                        will know about (most noticeably, an icon).
    2090   */
    2091  function quiz_get_coursemodule_info($coursemodule) {
    2092      global $DB;
    2093  
    2094      $dbparams = ['id' => $coursemodule->instance];
    2095      $fields = 'id, name, intro, introformat, completionattemptsexhausted, completionpass, completionminattempts,
    2096          timeopen, timeclose';
    2097      if (!$quiz = $DB->get_record('quiz', $dbparams, $fields)) {
    2098          return false;
    2099      }
    2100  
    2101      $result = new cached_cm_info();
    2102      $result->name = $quiz->name;
    2103  
    2104      if ($coursemodule->showdescription) {
    2105          // Convert intro to html. Do not filter cached version, filters run at display time.
    2106          $result->content = format_module_intro('quiz', $quiz, $coursemodule->id, false);
    2107      }
    2108  
    2109      // Populate the custom completion rules as key => value pairs, but only if the completion mode is 'automatic'.
    2110      if ($coursemodule->completion == COMPLETION_TRACKING_AUTOMATIC) {
    2111          if ($quiz->completionpass || $quiz->completionattemptsexhausted) {
    2112              $result->customdata['customcompletionrules']['completionpassorattemptsexhausted'] = [
    2113                  'completionpass' => $quiz->completionpass,
    2114                  'completionattemptsexhausted' => $quiz->completionattemptsexhausted,
    2115              ];
    2116          } else {
    2117              $result->customdata['customcompletionrules']['completionpassorattemptsexhausted'] = [];
    2118          }
    2119  
    2120          $result->customdata['customcompletionrules']['completionminattempts'] = $quiz->completionminattempts;
    2121      }
    2122  
    2123      // Populate some other values that can be used in calendar or on dashboard.
    2124      if ($quiz->timeopen) {
    2125          $result->customdata['timeopen'] = $quiz->timeopen;
    2126      }
    2127      if ($quiz->timeclose) {
    2128          $result->customdata['timeclose'] = $quiz->timeclose;
    2129      }
    2130  
    2131      return $result;
    2132  }
    2133  
    2134  /**
    2135   * Sets dynamic information about a course module
    2136   *
    2137   * This function is called from cm_info when displaying the module
    2138   *
    2139   * @param cm_info $cm
    2140   */
    2141  function mod_quiz_cm_info_dynamic(cm_info $cm) {
    2142      global $USER;
    2143  
    2144      $cache = cache::make('mod_quiz', 'overrides');
    2145      $override = $cache->get("{$cm->instance}_u_{$USER->id}");
    2146  
    2147      if (!$override) {
    2148          $override = (object) [
    2149              'timeopen' => null,
    2150              'timeclose' => null,
    2151          ];
    2152      }
    2153  
    2154      // No need to look for group overrides if there are user overrides for both timeopen and timeclose.
    2155      if (is_null($override->timeopen) || is_null($override->timeclose)) {
    2156          $opens = [];
    2157          $closes = [];
    2158          $groupings = groups_get_user_groups($cm->course, $USER->id);
    2159          foreach ($groupings[0] as $groupid) {
    2160              $groupoverride = $cache->get("{$cm->instance}_g_{$groupid}");
    2161              if (isset($groupoverride->timeopen)) {
    2162                  $opens[] = $groupoverride->timeopen;
    2163              }
    2164              if (isset($groupoverride->timeclose)) {
    2165                  $closes[] = $groupoverride->timeclose;
    2166              }
    2167          }
    2168          // If there is a user override for a setting, ignore the group override.
    2169          if (is_null($override->timeopen) && count($opens)) {
    2170              $override->timeopen = min($opens);
    2171          }
    2172          if (is_null($override->timeclose) && count($closes)) {
    2173              if (in_array(0, $closes)) {
    2174                  $override->timeclose = 0;
    2175              } else {
    2176                  $override->timeclose = max($closes);
    2177              }
    2178          }
    2179      }
    2180  
    2181      // Populate some other values that can be used in calendar or on dashboard.
    2182      if (!is_null($override->timeopen)) {
    2183          $cm->override_customdata('timeopen', $override->timeopen);
    2184      }
    2185      if (!is_null($override->timeclose)) {
    2186          $cm->override_customdata('timeclose', $override->timeclose);
    2187      }
    2188  }
    2189  
    2190  /**
    2191   * Callback which returns human-readable strings describing the active completion custom rules for the module instance.
    2192   *
    2193   * @param cm_info|stdClass $cm object with fields ->completion and ->customdata['customcompletionrules']
    2194   * @return array $descriptions the array of descriptions for the custom rules.
    2195   */
    2196  function mod_quiz_get_completion_active_rule_descriptions($cm) {
    2197      // Values will be present in cm_info, and we assume these are up to date.
    2198      if (empty($cm->customdata['customcompletionrules'])
    2199          || $cm->completion != COMPLETION_TRACKING_AUTOMATIC) {
    2200          return [];
    2201      }
    2202  
    2203      $descriptions = [];
    2204      $rules = $cm->customdata['customcompletionrules'];
    2205  
    2206      if (!empty($rules['completionpassorattemptsexhausted'])) {
    2207          if (!empty($rules['completionpassorattemptsexhausted']['completionattemptsexhausted'])) {
    2208              $descriptions[] = get_string('completionpassorattemptsexhausteddesc', 'quiz');
    2209          } else if (!empty($rules['completionpassorattemptsexhausted']['completionpass'])) {
    2210              $descriptions[] = get_string('completionpassdesc', 'quiz',
    2211                  format_time($rules['completionpassorattemptsexhausted']['completionpass']));
    2212          }
    2213      } else {
    2214          // Fallback.
    2215          if (!empty($rules['completionattemptsexhausted'])) {
    2216              $descriptions[] = get_string('completionpassorattemptsexhausteddesc', 'quiz');
    2217          } else if (!empty($rules['completionpass'])) {
    2218              $descriptions[] = get_string('completionpassdesc', 'quiz', format_time($rules['completionpass']));
    2219          }
    2220      }
    2221  
    2222      if (!empty($rules['completionminattempts'])) {
    2223          $descriptions[] = get_string('completionminattemptsdesc', 'quiz', $rules['completionminattempts']);
    2224      }
    2225  
    2226      return $descriptions;
    2227  }
    2228  
    2229  /**
    2230   * Returns the min and max values for the timestart property of a quiz
    2231   * activity event.
    2232   *
    2233   * The min and max values will be the timeopen and timeclose properties
    2234   * of the quiz, respectively, if they are set.
    2235   *
    2236   * If either value isn't set then null will be returned instead to
    2237   * indicate that there is no cutoff for that value.
    2238   *
    2239   * If the vent has no valid timestart range then [false, false] will
    2240   * be returned. This is the case for overriden events.
    2241   *
    2242   * A minimum and maximum cutoff return value will look like:
    2243   * [
    2244   *     [1505704373, 'The date must be after this date'],
    2245   *     [1506741172, 'The date must be before this date']
    2246   * ]
    2247   *
    2248   * @throws \moodle_exception
    2249   * @param \calendar_event $event The calendar event to get the time range for
    2250   * @param stdClass $quiz The module instance to get the range from
    2251   * @return array
    2252   */
    2253  function mod_quiz_core_calendar_get_valid_event_timestart_range(\calendar_event $event, \stdClass $quiz) {
    2254      global $CFG, $DB;
    2255      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
    2256  
    2257      // Overrides do not have a valid timestart range.
    2258      if (quiz_is_overriden_calendar_event($event)) {
    2259          return [false, false];
    2260      }
    2261  
    2262      $mindate = null;
    2263      $maxdate = null;
    2264  
    2265      if ($event->eventtype == QUIZ_EVENT_TYPE_OPEN) {
    2266          if (!empty($quiz->timeclose)) {
    2267              $maxdate = [
    2268                  $quiz->timeclose,
    2269                  get_string('openafterclose', 'quiz')
    2270              ];
    2271          }
    2272      } else if ($event->eventtype == QUIZ_EVENT_TYPE_CLOSE) {
    2273          if (!empty($quiz->timeopen)) {
    2274              $mindate = [
    2275                  $quiz->timeopen,
    2276                  get_string('closebeforeopen', 'quiz')
    2277              ];
    2278          }
    2279      }
    2280  
    2281      return [$mindate, $maxdate];
    2282  }
    2283  
    2284  /**
    2285   * This function will update the quiz module according to the
    2286   * event that has been modified.
    2287   *
    2288   * It will set the timeopen or timeclose value of the quiz instance
    2289   * according to the type of event provided.
    2290   *
    2291   * @throws \moodle_exception
    2292   * @param \calendar_event $event A quiz activity calendar event
    2293   * @param \stdClass $quiz A quiz activity instance
    2294   */
    2295  function mod_quiz_core_calendar_event_timestart_updated(\calendar_event $event, \stdClass $quiz) {
    2296      global $CFG, $DB;
    2297      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
    2298  
    2299      if (!in_array($event->eventtype, [QUIZ_EVENT_TYPE_OPEN, QUIZ_EVENT_TYPE_CLOSE])) {
    2300          // This isn't an event that we care about so we can ignore it.
    2301          return;
    2302      }
    2303  
    2304      $courseid = $event->courseid;
    2305      $modulename = $event->modulename;
    2306      $instanceid = $event->instance;
    2307      $modified = false;
    2308      $closedatechanged = false;
    2309  
    2310      // Something weird going on. The event is for a different module so
    2311      // we should ignore it.
    2312      if ($modulename != 'quiz') {
    2313          return;
    2314      }
    2315  
    2316      if ($quiz->id != $instanceid) {
    2317          // The provided quiz instance doesn't match the event so
    2318          // there is nothing to do here.
    2319          return;
    2320      }
    2321  
    2322      // We don't update the activity if it's an override event that has
    2323      // been modified.
    2324      if (quiz_is_overriden_calendar_event($event)) {
    2325          return;
    2326      }
    2327  
    2328      $coursemodule = get_fast_modinfo($courseid)->instances[$modulename][$instanceid];
    2329      $context = context_module::instance($coursemodule->id);
    2330  
    2331      // The user does not have the capability to modify this activity.
    2332      if (!has_capability('moodle/course:manageactivities', $context)) {
    2333          return;
    2334      }
    2335  
    2336      if ($event->eventtype == QUIZ_EVENT_TYPE_OPEN) {
    2337          // If the event is for the quiz activity opening then we should
    2338          // set the start time of the quiz activity to be the new start
    2339          // time of the event.
    2340          if ($quiz->timeopen != $event->timestart) {
    2341              $quiz->timeopen = $event->timestart;
    2342              $modified = true;
    2343          }
    2344      } else if ($event->eventtype == QUIZ_EVENT_TYPE_CLOSE) {
    2345          // If the event is for the quiz activity closing then we should
    2346          // set the end time of the quiz activity to be the new start
    2347          // time of the event.
    2348          if ($quiz->timeclose != $event->timestart) {
    2349              $quiz->timeclose = $event->timestart;
    2350              $modified = true;
    2351              $closedatechanged = true;
    2352          }
    2353      }
    2354  
    2355      if ($modified) {
    2356          $quiz->timemodified = time();
    2357          $DB->update_record('quiz', $quiz);
    2358  
    2359          if ($closedatechanged) {
    2360              quiz_update_open_attempts(array('quizid' => $quiz->id));
    2361          }
    2362  
    2363          // Delete any previous preview attempts.
    2364          quiz_delete_previews($quiz);
    2365          quiz_update_events($quiz);
    2366          $event = \core\event\course_module_updated::create_from_cm($coursemodule, $context);
    2367          $event->trigger();
    2368      }
    2369  }
    2370  
    2371  /**
    2372   * Generates the question bank in a fragment output. This allows
    2373   * the question bank to be displayed in a modal.
    2374   *
    2375   * The only expected argument provided in the $args array is
    2376   * 'querystring'. The value should be the list of parameters
    2377   * URL encoded and used to build the question bank page.
    2378   *
    2379   * The individual list of parameters expected can be found in
    2380   * question_build_edit_resources.
    2381   *
    2382   * @param array $args The fragment arguments.
    2383   * @return string The rendered mform fragment.
    2384   */
    2385  function mod_quiz_output_fragment_quiz_question_bank($args) {
    2386      global $CFG, $DB, $PAGE;
    2387      require_once($CFG->dirroot . '/mod/quiz/locallib.php');
    2388      require_once($CFG->dirroot . '/question/editlib.php');
    2389  
    2390      $querystring = preg_replace('/^\?/', '', $args['querystring']);
    2391      $params = [];
    2392      parse_str($querystring, $params);
    2393  
    2394      // Build the required resources. The $params are all cleaned as
    2395      // part of this process.
    2396      list($thispageurl, $contexts, $cmid, $cm, $quiz, $pagevars) =
    2397              question_build_edit_resources('editq', '/mod/quiz/edit.php', $params);
    2398  
    2399      // Get the course object and related bits.
    2400      $course = $DB->get_record('course', array('id' => $quiz->course), '*', MUST_EXIST);
    2401      require_capability('mod/quiz:manage', $contexts->lowest());
    2402  
    2403      // Create quiz question bank view.
    2404      $questionbank = new mod_quiz\question\bank\custom_view($contexts, $thispageurl, $course, $cm, $quiz);
    2405      $questionbank->set_quiz_has_attempts(quiz_has_attempts($quiz->id));
    2406  
    2407      // Output.
    2408      $renderer = $PAGE->get_renderer('mod_quiz', 'edit');
    2409      return $renderer->question_bank_contents($questionbank, $pagevars);
    2410  }
    2411  
    2412  /**
    2413   * Generates the add random question in a fragment output. This allows the
    2414   * form to be rendered in javascript, for example inside a modal.
    2415   *
    2416   * The required arguments as keys in the $args array are:
    2417   *      cat {string} The category and category context ids comma separated.
    2418   *      addonpage {int} The page id to add this question to.
    2419   *      returnurl {string} URL to return to after form submission.
    2420   *      cmid {int} The course module id the questions are being added to.
    2421   *
    2422   * @param array $args The fragment arguments.
    2423   * @return string The rendered mform fragment.
    2424   */
    2425  function mod_quiz_output_fragment_add_random_question_form($args) {
    2426      global $CFG;
    2427      require_once($CFG->dirroot . '/mod/quiz/addrandomform.php');
    2428  
    2429      $contexts = new \question_edit_contexts($args['context']);
    2430      $formoptions = [
    2431          'contexts' => $contexts,
    2432          'cat' => $args['cat']
    2433      ];
    2434      $formdata = [
    2435          'category' => $args['cat'],
    2436          'addonpage' => $args['addonpage'],
    2437          'returnurl' => $args['returnurl'],
    2438          'cmid' => $args['cmid']
    2439      ];
    2440  
    2441      $form = new quiz_add_random_form(
    2442          new \moodle_url('/mod/quiz/addrandom.php'),
    2443          $formoptions,
    2444          'post',
    2445          '',
    2446          null,
    2447          true,
    2448          $formdata
    2449      );
    2450      $form->set_data($formdata);
    2451  
    2452      return $form->render();
    2453  }