1<?php
2// This file is part of Moodle - http://moodle.org/
3//
4// Moodle is free software: you can redistribute it and/or modify
5// it under the terms of the GNU General Public License as published by
6// the Free Software Foundation, either version 3 of the License, or
7// (at your option) any later version.
8//
9// Moodle is distributed in the hope that it will be useful,
10// but WITHOUT ANY WARRANTY; without even the implied warranty of
11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12// GNU General Public License for more details.
13//
14// You should have received a copy of the GNU General Public License
15// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
16
17/**
18 * Event observer for meta enrolment plugin.
19 *
20 * @package    enrol_meta
21 * @copyright  2013 Rajesh Taneja <rajesh@moodle.com>
22 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
23 */
24
25defined('MOODLE_INTERNAL') || die();
26
27require_once($CFG->dirroot.'/enrol/meta/locallib.php');
28
29/**
30 * Event observer for enrol_meta.
31 *
32 * @package    enrol_meta
33 * @copyright  2013 Rajesh Taneja <rajesh@moodle.com>
34 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
35 */
36class enrol_meta_observer extends enrol_meta_handler {
37
38    /**
39     * Triggered via user_enrolment_created event.
40     *
41     * @param \core\event\user_enrolment_created $event
42     * @return bool true on success.
43     */
44    public static function user_enrolment_created(\core\event\user_enrolment_created $event) {
45        if (!enrol_is_enabled('meta')) {
46            // No more enrolments for disabled plugins.
47            return true;
48        }
49
50        if ($event->other['enrol'] === 'meta') {
51            // Prevent circular dependencies - we can not sync meta enrolments recursively.
52            return true;
53        }
54
55        self::sync_course_instances($event->courseid, $event->relateduserid);
56        return true;
57    }
58
59    /**
60     * Triggered via user_enrolment_deleted event.
61     *
62     * @param \core\event\user_enrolment_deleted $event
63     * @return bool true on success.
64     */
65    public static function user_enrolment_deleted(\core\event\user_enrolment_deleted $event) {
66        if (!enrol_is_enabled('meta')) {
67            // This is slow, let enrol_meta_sync() deal with disabled plugin.
68            return true;
69        }
70
71        if ($event->other['enrol'] === 'meta') {
72            // Prevent circular dependencies - we can not sync meta enrolments recursively.
73            return true;
74        }
75
76        self::sync_course_instances($event->courseid, $event->relateduserid);
77
78        return true;
79    }
80
81    /**
82     * Triggered via user_enrolment_updated event.
83     *
84     * @param \core\event\user_enrolment_updated $event
85     * @return bool true on success
86     */
87    public static function user_enrolment_updated(\core\event\user_enrolment_updated $event) {
88        if (!enrol_is_enabled('meta')) {
89            // No modifications if plugin disabled.
90            return true;
91        }
92
93        if ($event->other['enrol'] === 'meta') {
94            // Prevent circular dependencies - we can not sync meta enrolments recursively.
95            return true;
96        }
97
98        self::sync_course_instances($event->courseid, $event->relateduserid);
99
100        return true;
101    }
102
103    /**
104     * Triggered via role_assigned event.
105     *
106     * @param \core\event\role_assigned $event
107     * @return bool true on success.
108     */
109    public static function role_assigned(\core\event\role_assigned $event) {
110        if (!enrol_is_enabled('meta')) {
111            return true;
112        }
113
114        // Prevent circular dependencies - we can not sync meta roles recursively.
115        if ($event->other['component'] === 'enrol_meta') {
116            return true;
117        }
118
119        // Only course level roles are interesting.
120        if (!$parentcontext = context::instance_by_id($event->contextid, IGNORE_MISSING)) {
121            return true;
122        }
123        if ($parentcontext->contextlevel != CONTEXT_COURSE) {
124            return true;
125        }
126
127        self::sync_course_instances($parentcontext->instanceid, $event->relateduserid);
128
129        return true;
130    }
131
132    /**
133     * Triggered via role_unassigned event.
134     *
135     * @param \core\event\role_unassigned $event
136     * @return bool true on success
137     */
138    public static function role_unassigned(\core\event\role_unassigned $event) {
139        if (!enrol_is_enabled('meta')) {
140            // All roles are removed via cron automatically.
141            return true;
142        }
143
144        // Prevent circular dependencies - we can not sync meta roles recursively.
145        if ($event->other['component'] === 'enrol_meta') {
146            return true;
147        }
148
149        // Only course level roles are interesting.
150        if (!$parentcontext = context::instance_by_id($event->contextid, IGNORE_MISSING)) {
151            return true;
152        }
153        if ($parentcontext->contextlevel != CONTEXT_COURSE) {
154            return true;
155        }
156
157        self::sync_course_instances($parentcontext->instanceid, $event->relateduserid);
158
159        return true;
160    }
161
162    /**
163     * Triggered via course_deleted event.
164     *
165     * @param \core\event\course_deleted $event
166     * @return bool true on success
167     */
168    public static function course_deleted(\core\event\course_deleted $event) {
169        global $DB;
170
171        if (!enrol_is_enabled('meta')) {
172            // This is slow, let enrol_meta_sync() deal with disabled plugin.
173            return true;
174        }
175
176        // Does anything want to sync with this parent?
177        if (!$enrols = $DB->get_records('enrol', array('customint1' => $event->objectid, 'enrol' => 'meta'),
178                'courseid ASC, id ASC')) {
179            return true;
180        }
181
182        $plugin = enrol_get_plugin('meta');
183        $unenrolaction = $plugin->get_config('unenrolaction', ENROL_EXT_REMOVED_SUSPENDNOROLES);
184
185        if ($unenrolaction == ENROL_EXT_REMOVED_UNENROL) {
186            // Simple, just delete this instance which purges all enrolments,
187            // admins were warned that this is risky setting!
188            foreach ($enrols as $enrol) {
189                $plugin->delete_instance($enrol);
190            }
191            return true;
192        }
193
194        foreach ($enrols as $enrol) {
195            if ($unenrolaction == ENROL_EXT_REMOVED_SUSPEND or $unenrolaction == ENROL_EXT_REMOVED_SUSPENDNOROLES) {
196                // This makes all enrolments suspended very quickly.
197                $plugin->update_status($enrol, ENROL_INSTANCE_DISABLED);
198            }
199            if ($unenrolaction == ENROL_EXT_REMOVED_SUSPENDNOROLES) {
200                $context = context_course::instance($enrol->courseid);
201                role_unassign_all(array('contextid'=>$context->id, 'component'=>'enrol_meta', 'itemid'=>$enrol->id));
202            }
203        }
204
205        return true;
206    }
207
208    /**
209     * Triggered via enrol_instance_updated event.
210     *
211     * @param \core\event\enrol_instance_updated $event
212     * @return boolean
213     */
214    public static function enrol_instance_updated(\core\event\enrol_instance_updated $event) {
215        global $DB;
216
217        if (!enrol_is_enabled('meta')) {
218            // This is slow, let enrol_meta_sync() deal with disabled plugin.
219            return true;
220        }
221
222        // Does anything want to sync with this parent?
223        $affectedcourses = $DB->get_fieldset_sql('SELECT DISTINCT courseid FROM {enrol} '.
224                'WHERE customint1 = ? AND enrol = ?',
225                array($event->courseid, 'meta'));
226
227        foreach ($affectedcourses as $courseid) {
228            enrol_meta_sync($courseid);
229        }
230
231        return true;
232    }
233}
234