/**
* Sync all jwc course links.
* @param int $courseid one course, empty mean all
* @return void
*/
function enrol_jwc_sync($courseid = NULL)
{
global $CFG, $DB;
// unfortunately this may take a long time
@set_time_limit(0);
//if this fails during upgrade we can continue from cron, no big deal
$jwc = new jwc_helper();
$jwc_enrol = enrol_get_plugin('jwc');
if (enrol_is_enabled('jwc')) {
$params = array();
$onecourse = "";
if ($courseid) {
$params['courseid'] = $courseid;
$onecourse = "AND courseid = :courseid";
}
$select = "enrol = :jwc AND status = :status {$onecourse}";
$params['jwc'] = 'jwc';
$params['status'] = ENROL_INSTANCE_ENABLED;
$instances = $DB->get_records_select('enrol', $select, $params);
foreach ($instances as $instance) {
// 课程必须有cas认证的教师
$teachers = enrol_jwc_get_cas_teachers($instance->courseid);
if (empty($teachers)) {
$DB->set_field('enrol', 'customchar2', '此课程没有使用HITID的教师', array('id' => $instance->id));
continue;
}
// 从教务处获取所有选修该课程的学生
$return_msg = '';
$students = $jwc->get_students($instance->customchar1, $teachers, $jwc_enrol->get_config('semester'), $return_msg);
$DB->set_field('enrol', 'customchar2', $return_msg, array('id' => $instance->id));
if (!$students) {
// 出错
continue;
// skip this instance. 就算出错，也别清理选课，以免意外。管理员更改学期名时再清理所有选课
}
// 开始同步
// 选课
foreach ($students as $userid) {
$jwc_enrol->enrol_user($instance, $userid, $instance->roleid);
}
// 取消教务处删除的选课
if (empty($students)) {
$where = "enrolid = {$instance->id}";
} else {
$where = "enrolid = {$instance->id} AND userid NOT IN (" . implode(',', $students) . ')';
}
$ues = $DB->get_records_select('user_enrolments', $where);
foreach ($ues as $ue) {
$jwc_enrol->unenrol_user($instance, $ue->userid);
}
}
}
}
/**
* Given a courseid this function returns true if the user is able to enrol or configure jwc
*
* @param int $courseid
* @return bool
*/
protected function can_add_new_instances($courseid)
{
global $DB, $CFG;
$coursecontext = get_context_instance(CONTEXT_COURSE, $courseid);
if (!has_capability('moodle/course:enrolconfig', $coursecontext) or !has_capability('enrol/jwc:config', $coursecontext)) {
return false;
}
require_once "{$CFG->dirroot}/enrol/jwc/locallib.php";
if (!enrol_jwc_get_cas_teachers($courseid)) {
// 课程中必须有使用cas认证的教师
return false;
}
return true;
}