locallib.php

<?php

// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * Local stuff for jwc enrolment plugin.
 *
 * @package    enrol
 * @subpackage jwc
 * @copyright  2010 Petr Skoda {@link http://skodak.org}
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

defined('MOODLE_INTERNAL') || die();

require_once($CFG->dirroot . '/enrol/locallib.php');
require_once($CFG->dirroot . '/enrol/jwc/jwc.php');


/**
 * 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);
            }
        }
    }
}

function enrol_jwc_get_cas_teachers($courseid) {
    global $DB;

    $jwc_enrol = enrol_get_plugin('jwc');
    $teacherroleid = $jwc_enrol->get_config('teacherroleid');
    $context = get_context_instance(CONTEXT_COURSE, $courseid);

    $where = 'auth = :auth AND id IN (SELECT userid FROM {role_assignments} WHERE roleid = :roleid AND contextid = :contextid )';
    return $DB->get_records_select('user', $where, array('auth' => 'cas', 'roleid' => $teacherroleid, 'contextid' => $context->id));
}