<?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/>.

/**
 * Upgrade code for the chat activity
 *
 * @package   mod_chat
 * @copyright 2006 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

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

function xmldb_chat_upgrade($oldversion) {

<     global $CFG;



>     global $CFG, $DB;




<     // Automatically generated Moodle v3.6.0 release upgrade line.
<     // Put any upgrade step following this.
< 
<     // Automatically generated Moodle v3.7.0 release upgrade line.
<     // Put any upgrade step following this.



>     require_once($CFG->libdir.'/db/upgradelib.php'); // Core Upgrade-related functions.




<     // Automatically generated Moodle v3.8.0 release upgrade line.
<     // Put any upgrade step following this.



>     $dbman = $DB->get_manager(); // Loads ddl manager and xmldb classes.



    // Automatically generated Moodle v3.9.0 release upgrade line.
    // Put any upgrade step following this.

    // Automatically generated Moodle v4.0.0 release upgrade line.

>     // Put any upgrade step following this.
    // Put any upgrade step following this.
>     if ($oldversion < 2022053000) {

>         // Define key course (foreign) to be added to chat_users.
    return true;
>         $table = new xmldb_table('chat_users');
}
>         $key = new xmldb_key('course', XMLDB_KEY_FOREIGN, ['course'], 'course', ['id']);
>         // Launch add key course.
>         $dbman->add_key($table, $key);
> 
>         // Chat savepoint reached.
>         upgrade_mod_savepoint(true, 2022053000, 'chat');
>     }
> 
>     // Automatically generated Moodle v4.1.0 release upgrade line.