public function addPresForUser($usr_id)
{
// begin transaction
global $db;
$db->beginTransaction();
try {
// Check if the user currently has a presentation for this session.
// If so, remove it.
// The loop is a bit of overkill, but in case of an erroneous situation of the user having multiple
// presentations for the same session, this will remove those extra cases.
//
// Include a check to make sure that presenters don't overwrite their presentations through this method.
$presentations = get_presentations_by_user_by_session($usr_id, $this->ses_id);
foreach ($presentations as $presentation) {
Presentation::deletePresentationsByUser($usr_id, $presentation['pres_id']);
}
// Inserts the new session for the user.
$this->insert_presentation_for_user($usr_id);
// commit transaction
$db->commit();
} catch (PDOException $e) {
// roll back transaction
$db->rollback();
// log any errors to file
log_pdo_exception($e, $usr_id, "Adding Presentation:" . $this, "addPresForUser");
display_db_exception($e);
// display_error("Error saving data.");
exit;
}
}
