print_error('invalidcourse');
}
$courseid = $course->id;
require_login($course);
$context = get_context_instance(CONTEXT_COURSE, $courseid);
require_capability('moodle/course:managegroups', $context);
$returnurl = $CFG->wwwroot . '/group/index.php?id=' . $courseid . '&group=' . $group->id;
if (optional_param('cancel', false, PARAM_BOOL)) {
redirect($returnurl);
}
$groupmembersselector = new group_members_selector('removeselect', array('groupid' => $groupid, 'courseid' => $course->id));
$groupmembersselector->set_extra_fields(array());
$potentialmembersselector = new group_non_members_selector('addselect', array('groupid' => $groupid, 'courseid' => $course->id));
$potentialmembersselector->set_extra_fields(array());
if (optional_param('add', false, PARAM_BOOL) && confirm_sesskey()) {
$userstoadd = $potentialmembersselector->get_selected_users();
if (!empty($userstoadd)) {
foreach ($userstoadd as $user) {
if (!groups_add_member($groupid, $user->id)) {
print_error('erroraddremoveuser', 'group', $returnurl);
}
$groupmembersselector->invalidate_selected_users();
$potentialmembersselector->invalidate_selected_users();
}
}
}
if (optional_param('remove', false, PARAM_BOOL) && confirm_sesskey()) {
$userstoremove = $groupmembersselector->get_selected_users();
if (!empty($userstoremove)) {
foreach ($userstoremove as $user) {
if (!groups_remove_member($groupid, $user->id)) {
