/**
* Delete the current preview, if any, and redirect to start a new preview.
* @param int $previewid
* @param int $questionid
* @param object $displayoptions
* @param object $context
*/
function restart_preview($previewid, $questionid, $displayoptions, $context)
{
global $DB;
if ($previewid) {
$transaction = $DB->start_delegated_transaction();
question_engine::delete_questions_usage_by_activity($previewid);
$transaction->allow_commit();
}
redirect(question_preview_url($questionid, $displayoptions->behaviour, $displayoptions->maxmark, $displayoptions, $displayoptions->variant, $context));
}
protected function delete_quba()
{
question_engine::delete_questions_usage_by_activity($this->quba->get_id());
$this->quba = null;
}
/**
* Delete a quiz attempt.
* @param mixed $attempt an integer attempt id or an attempt object
* (row of the quiz_attempts table).
* @param object $quiz the quiz object.
*/
function quiz_delete_attempt($attempt, $quiz) {
global $DB;
if (is_numeric($attempt)) {
if (!$attempt = $DB->get_record('quiz_attempts', array('id' => $attempt))) {
return;
}
}
if ($attempt->quiz != $quiz->id) {
debugging("Trying to delete attempt $attempt->id which belongs to quiz $attempt->quiz " .
"but was passed quiz $quiz->id.");
return;
}
question_engine::delete_questions_usage_by_activity($attempt->uniqueid);
$DB->delete_records('quiz_attempts', array('id' => $attempt->id));
// Search quiz_attempts for other instances by this user.
// If none, then delete record for this quiz, this user from quiz_grades
// else recalculate best grade.
$userid = $attempt->userid;
if (!$DB->record_exists('quiz_attempts', array('userid' => $userid, 'quiz' => $quiz->id))) {
$DB->delete_records('quiz_grades', array('userid' => $userid, 'quiz' => $quiz->id));
} else {
quiz_save_best_grade($quiz, $userid);
}
quiz_update_grades($quiz, $userid);
}
/**
* Delete a quiz attempt.
* @param mixed $attempt an integer attempt id or an attempt object
* (row of the quiz_attempts table).
* @param object $quiz the quiz object.
*/
function quiz_delete_attempt($attempt, $quiz)
{
global $DB;
if (is_numeric($attempt)) {
if (!($attempt = $DB->get_record('quiz_attempts', array('id' => $attempt)))) {
return;
}
}
if ($attempt->quiz != $quiz->id) {
debugging("Trying to delete attempt {$attempt->id} which belongs to quiz {$attempt->quiz} " . "but was passed quiz {$quiz->id}.");
return;
}
if (!isset($quiz->cmid)) {
$cm = get_coursemodule_from_instance('quiz', $quiz->id, $quiz->course);
$quiz->cmid = $cm->id;
}
question_engine::delete_questions_usage_by_activity($attempt->uniqueid);
$DB->delete_records('quiz_attempts', array('id' => $attempt->id));
// Log the deletion of the attempt.
$params = array('objectid' => $attempt->id, 'relateduserid' => $attempt->userid, 'context' => context_module::instance($quiz->cmid), 'other' => array('quizid' => $quiz->id));
$event = \mod_quiz\event\attempt_deleted::create($params);
$event->add_record_snapshot('quiz_attempts', $attempt);
$event->trigger();
// Search quiz_attempts for other instances by this user.
// If none, then delete record for this quiz, this user from quiz_grades
// else recalculate best grade.
$userid = $attempt->userid;
if (!$DB->record_exists('quiz_attempts', array('userid' => $userid, 'quiz' => $quiz->id))) {
$DB->delete_records('quiz_grades', array('userid' => $userid, 'quiz' => $quiz->id));
} else {
quiz_save_best_grade($quiz, $userid);
}
quiz_update_grades($quiz, $userid);
}
/**
* Deletes a given paper copy question_usage_by_id; enforcing permissions and removing quiz_attempts, if applicable.
* If preserve_associated is not set, and the paper copy QUBA is associated with a quiz attempt, the quiz attempt will be deleted.
*
* @param int $usage_id The ID of the QUBA to be deleted.
* @param bool $preserve_associated If true, then any quiz with an associated quiz_attempt will not be deleted.
*
*/
protected function delete_usage($usage_id, $preserve_associated = false)
{
//require the user to be able to delete quizzes
require_capability('mod/quiz:deleteattempts', $this->context);
//if the usage is associated with a quiz object, remove the association before deleting
if ($this->is_associated($usage_id)) {
//if we've been instructed to preserve associated usages, then return without deleting the usage
if ($preserve_associated) {
return;
}
//otherwise, disassociate the usage
$this->disassociate_usage($usage_id);
}
//delete the usage
question_engine::delete_questions_usage_by_activity($usage_id);
}
/**
* Deletes the question usages by activity for an offlinequiz. This function must not be
* called if the offline quiz has attempts or scanned pages
*
* @param object $offlinequiz
*/
function offlinequiz_delete_template_usages($offlinequiz, $deletefiles = true)
{
global $CFG, $DB, $OUTPUT;
if ($groups = $DB->get_records('offlinequiz_groups', array('offlinequizid' => $offlinequiz->id), 'number', '*', 0, $offlinequiz->numgroups)) {
foreach ($groups as $group) {
if ($group->templateusageid) {
question_engine::delete_questions_usage_by_activity($group->templateusageid);
$group->templateusageid = 0;
$DB->set_field('offlinequiz_groups', 'templateusageid', 0, array('id' => $group->id));
}
}
}
// Also delete the PDF forms if they have been created.
if ($deletefiles) {
return offlinequiz_delete_pdf_forms($offlinequiz);
} else {
return $offlinequiz;
}
}
