<?php
// This file is part of Moodle - https://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/>.

/**
 * Defines settingpages and externalpages under the "server" category.
 *
 * @package     core
 * @category    admin
 * @copyright   2006 Martin Dougiamas
 * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

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

if ($hassiteconfig) {
    // System paths.
    $temp = new admin_settingpage('systempaths', new lang_string('systempaths', 'admin'));
    $temp->add(new admin_setting_configexecutable('pathtophp', new lang_string('pathtophp', 'admin'),
        new lang_string('configpathtophp', 'admin'), ''));
    $temp->add(new admin_setting_configexecutable('pathtodu', new lang_string('pathtodu', 'admin'),
        new lang_string('configpathtodu', 'admin'), ''));
    $temp->add(new admin_setting_configexecutable('aspellpath', new lang_string('aspellpath', 'admin'),
        new lang_string('edhelpaspellpath'), ''));
    $temp->add(new admin_setting_configexecutable('pathtodot', new lang_string('pathtodot', 'admin'),
        new lang_string('pathtodot_help', 'admin'), ''));
    $temp->add(new admin_setting_configexecutable('pathtogs', new lang_string('pathtogs', 'admin'),
        new lang_string('pathtogs_help', 'admin'), '/usr/bin/gs'));
    $temp->add(new admin_setting_configexecutable('pathtopdftoppm', new lang_string('pathtopdftoppm', 'admin'),
        new lang_string('pathtopdftoppm_help', 'admin'), ''));
    $temp->add(new admin_setting_configexecutable('pathtopython', new lang_string('pathtopython', 'admin'),
        new lang_string('pathtopythondesc', 'admin'), ''));
    $ADMIN->add('server', $temp);

    // Support contact.
    $temp = new admin_settingpage('supportcontact', new lang_string('supportcontact', 'admin'));
    $primaryadmin = get_admin();
    if ($primaryadmin) {
        $primaryadminname = fullname($primaryadmin, true);
    } else {
        // No defaults during installation - admin user must be created first.
        $primaryadminname = null;
    }
    $temp->add(new admin_setting_configtext('supportname', new lang_string('supportname', 'admin'),
        new lang_string('configsupportname', 'admin'), $primaryadminname, PARAM_NOTAGS));
    $setting = new admin_setting_requiredtext('supportemail', new lang_string('supportemail', 'admin'),
        new lang_string('configsupportemail', 'admin'), null, PARAM_EMAIL);
    $setting->set_force_ltr(true);
    $temp->add($setting);
    $temp->add(new admin_setting_configtext('supportpage', new lang_string('supportpage', 'admin'),
        new lang_string('configsupportpage', 'admin'), '', PARAM_URL));
    $temp->add(new admin_setting_configselect('supportavailability', new lang_string('supportavailability', 'admin'),
        new lang_string('configsupportavailability', 'admin'), CONTACT_SUPPORT_AUTHENTICATED,
        [
            CONTACT_SUPPORT_ANYONE => new lang_string('availabletoanyone', 'admin'),
            CONTACT_SUPPORT_AUTHENTICATED => new lang_string('availabletoauthenticated', 'admin'),
            CONTACT_SUPPORT_DISABLED => new lang_string('disabled', 'admin'),
        ]
    ));
    $temp->add(new admin_setting_configtext('servicespage', new lang_string('servicespage', 'admin'),
        new lang_string('configservicespage', 'admin'), '', PARAM_URL));

    $ADMIN->add('server', $temp);

    // Session handling.
    $temp = new admin_settingpage('sessionhandling', new lang_string('sessionhandling', 'admin'));
    if (empty($CFG->session_handler_class) and $DB->session_lock_supported()) {
        $temp->add(new admin_setting_configcheckbox('dbsessions', new lang_string('dbsessions', 'admin'),
            new lang_string('configdbsessions', 'admin'), 0));
    }

    $temp->add(new admin_setting_configduration('sessiontimeout', new lang_string('sessiontimeout', 'admin'),
        new lang_string('configsessiontimeout', 'admin'), 8 * 60 * 60));

    $sessiontimeoutwarning = new admin_setting_configduration('sessiontimeoutwarning',
        new lang_string('sessiontimeoutwarning', 'admin'),
        new lang_string('configsessiontimeoutwarning', 'admin'), 20 * 60);

    $sessiontimeoutwarning->set_validate_function(function(int $value): string {
        global $CFG;
        // Check sessiontimeoutwarning is less than sessiontimeout.
        if ($CFG->sessiontimeout <= $value) {
            return get_string('configsessiontimeoutwarningcheck', 'admin');
        } else {
            return '';
        }
    });

    $temp->add($sessiontimeoutwarning);

    $temp->add(new admin_setting_configtext('sessioncookie', new lang_string('sessioncookie', 'admin'),
        new lang_string('configsessioncookie', 'admin'), '', PARAM_ALPHANUM));
    $temp->add(new admin_setting_configtext('sessioncookiepath', new lang_string('sessioncookiepath', 'admin'),
        new lang_string('configsessioncookiepath', 'admin'), '', PARAM_RAW));
    $temp->add(new admin_setting_configtext('sessioncookiedomain', new lang_string('sessioncookiedomain', 'admin'),
        new lang_string('configsessioncookiedomain', 'admin'), '', PARAM_RAW, 50));
    $ADMIN->add('server', $temp);

    // Statistics.
    $temp = new admin_settingpage('stats', new lang_string('stats'), 'moodle/site:config', empty($CFG->enablestats));
    $temp->add(new admin_setting_configselect('statsfirstrun', new lang_string('statsfirstrun', 'admin'),
        new lang_string('configstatsfirstrun', 'admin'), 'none',
        [
            'none' => new lang_string('none'),
            60 * 60 * 24 * 7 => new lang_string('numweeks', 'moodle', 1),
            60 * 60 * 24 * 14 => new lang_string('numweeks', 'moodle', 2),
            60 * 60 * 24 * 21 => new lang_string('numweeks', 'moodle', 3),
            60 * 60 * 24 * 28 => new lang_string('nummonths', 'moodle', 1),
            60 * 60 * 24 * 56 => new lang_string('nummonths', 'moodle', 2),
            60 * 60 * 24 * 84 => new lang_string('nummonths', 'moodle', 3),
            60 * 60 * 24 * 112 => new lang_string('nummonths', 'moodle', 4),
            60 * 60 * 24 * 140 => new lang_string('nummonths', 'moodle', 5),
            60 * 60 * 24 * 168 => new lang_string('nummonths', 'moodle', 6),
            'all' => new lang_string('all')
        ]
    ));
    $temp->add(new admin_setting_configselect('statsmaxruntime', new lang_string('statsmaxruntime', 'admin'),
        new lang_string('configstatsmaxruntime3', 'admin'), 0,
        [
            0 => new lang_string('untilcomplete'),
            60 * 30 => '10 ' . new lang_string('minutes'),
            60 * 30 => '30 ' . new lang_string('minutes'),
            60 * 60 => '1 ' . new lang_string('hour'),
            60 * 60 * 2 => '2 ' . new lang_string('hours'),
            60 * 60 * 3 => '3 ' . new lang_string('hours'),
            60 * 60 * 4 => '4 ' . new lang_string('hours'),
            60 * 60 * 5 => '5 ' . new lang_string('hours'),
            60 * 60 * 6 => '6 ' . new lang_string('hours'),
            60 * 60 * 7 => '7 ' . new lang_string('hours'),
            60 * 60 * 8 => '8 ' . new lang_string('hours'),
        ]
    ));
    $temp->add(new admin_setting_configtext('statsruntimedays', new lang_string('statsruntimedays', 'admin'),
        new lang_string('configstatsruntimedays', 'admin'), 31, PARAM_INT));
    $temp->add(new admin_setting_configtext('statsuserthreshold', new lang_string('statsuserthreshold', 'admin'),
        new lang_string('configstatsuserthreshold', 'admin'), 0, PARAM_INT));
    $ADMIN->add('server', $temp);

    // HTTP.
    $temp = new admin_settingpage('http', new lang_string('http', 'admin'));
    $temp->add(new admin_setting_configcheckbox('slasharguments', new lang_string('slasharguments', 'admin'),
        new lang_string('configslasharguments', 'admin'), 1));
    $temp->add(new admin_setting_heading('reverseproxy', new lang_string('reverseproxy', 'admin'), '', ''));
    $options = [
        0 => 'HTTP_CLIENT_IP, HTTP_X_FORWARDED_FOR, REMOTE_ADDR',
        GETREMOTEADDR_SKIP_HTTP_CLIENT_IP => 'HTTP_X_FORWARDED_FOR, REMOTE_ADDR',
        GETREMOTEADDR_SKIP_HTTP_X_FORWARDED_FOR => 'HTTP_CLIENT, REMOTE_ADDR',
        GETREMOTEADDR_SKIP_HTTP_X_FORWARDED_FOR | GETREMOTEADDR_SKIP_HTTP_CLIENT_IP => 'REMOTE_ADDR'
    ];
    $temp->add(new admin_setting_configselect('getremoteaddrconf', new lang_string('getremoteaddrconf', 'admin'),
        new lang_string('configgetremoteaddrconf', 'admin'),
        GETREMOTEADDR_SKIP_HTTP_X_FORWARDED_FOR | GETREMOTEADDR_SKIP_HTTP_CLIENT_IP, $options));
    $temp->add(new admin_setting_configtext('reverseproxyignore', new lang_string('reverseproxyignore', 'admin'),
        new lang_string('configreverseproxyignore', 'admin'), ''));

    $temp->add(new admin_setting_heading('webproxy', new lang_string('webproxy', 'admin'),
        new lang_string('webproxyinfo', 'admin')));
    $temp->add(new admin_setting_configtext('proxyhost', new lang_string('proxyhost', 'admin'),
        new lang_string('configproxyhost', 'admin'), '', PARAM_HOST));
    $temp->add(new admin_setting_configtext('proxyport', new lang_string('proxyport', 'admin'),
        new lang_string('configproxyport', 'admin'), 0, PARAM_INT));
    $options = ['HTTP' => 'HTTP'];
    if (defined('CURLPROXY_SOCKS5')) {
        $options['SOCKS5'] = 'SOCKS5';
    }
    $temp->add(new admin_setting_configselect('proxytype', new lang_string('proxytype', 'admin'),
        new lang_string('configproxytype', 'admin'), 'HTTP', $options));
    $temp->add(new admin_setting_configtext('proxyuser', new lang_string('proxyuser', 'admin'),
        new lang_string('configproxyuser', 'admin'), ''));
    $temp->add(new admin_setting_configpasswordunmask('proxypassword', new lang_string('proxypassword', 'admin'),
        new lang_string('configproxypassword', 'admin'), ''));

    $setting = new admin_setting_configtext('proxybypass', new lang_string('proxybypass', 'admin'),
        new lang_string('configproxybypass', 'admin'), 'localhost,127.0.0.1');
    $setting->set_updatedcallback(function() {
        // Normalize $CFG->proxybypass value.
        $normalizedvalue = \core\ip_utils::normalize_internet_address_list(get_config('core', 'proxybypass'));
        set_config('proxybypass', $normalizedvalue);
    });
    $temp->add($setting);

    $temp->add(new admin_setting_configcheckbox('proxylogunsafe', new lang_string('proxylogunsafe', 'admin'),
        new lang_string('configproxylogunsafe_help', 'admin'), 0));
    $temp->add(new admin_setting_configcheckbox('proxyfixunsafe', new lang_string('proxyfixunsafe', 'admin'),
        new lang_string('configproxyfixunsafe_help', 'admin'), 0));

    $ADMIN->add('server', $temp);

    $temp = new admin_settingpage('maintenancemode', new lang_string('sitemaintenancemode', 'admin'));
    $options = [0 => new lang_string('disable'), 1 => new lang_string('enable')];
    $temp->add(new admin_setting_configselect('maintenance_enabled', new lang_string('sitemaintenancemode', 'admin'),
        new lang_string('helpsitemaintenance', 'admin'), 0, $options));
    $temp->add(new admin_setting_confightmleditor('maintenance_message', new lang_string('optionalmaintenancemessage', 'admin'),
        '', ''));
    $ADMIN->add('server', $temp);

    // Cleanup.
    $temp = new admin_settingpage('cleanup', new lang_string('cleanup', 'admin'));
    $temp->add(new admin_setting_configselect('deleteunconfirmed', new lang_string('deleteunconfirmed', 'admin'),
        new lang_string('configdeleteunconfirmed', 'admin'), 168,
        [
            0 => new lang_string('never'),
            168 => new lang_string('numdays', '', 7),
            144 => new lang_string('numdays', '', 6),
            120 => new lang_string('numdays', '', 5),
            96 => new lang_string('numdays', '', 4),
            72 => new lang_string('numdays', '', 3),
            48 => new lang_string('numdays', '', 2),
            24 => new lang_string('numdays', '', 1),
            12 => new lang_string('numhours', '', 12),
            6 => new lang_string('numhours', '', 6),
            1 => new lang_string('numhours', '', 1),
        ]
    ));

    $temp->add(new admin_setting_configselect('deleteincompleteusers', new lang_string('deleteincompleteusers', 'admin'),
        new lang_string('configdeleteincompleteusers', 'admin'), 0,
        [
            0 => new lang_string('never'),
            168 => new lang_string('numdays', '', 7),
            144 => new lang_string('numdays', '', 6),
            120 => new lang_string('numdays', '', 5),
            96 => new lang_string('numdays', '', 4),
            72 => new lang_string('numdays', '', 3),
            48 => new lang_string('numdays', '', 2),
            24 => new lang_string('numdays', '', 1),
        ]
    ));

    $temp->add(new admin_setting_configcheckbox('disablegradehistory', new lang_string('disablegradehistory', 'grades'),
        new lang_string('disablegradehistory_help', 'grades'), 0));

    $temp->add(new admin_setting_configselect('gradehistorylifetime', new lang_string('gradehistorylifetime', 'grades'),
        new lang_string('gradehistorylifetime_help', 'grades'), 0,
        [
            0 => new lang_string('neverdeletehistory', 'grades'),
            1000 => new lang_string('numdays', '', 1000),
            365 => new lang_string('numdays', '', 365),
            180 => new lang_string('numdays', '', 180),
            150 => new lang_string('numdays', '', 150),
            120 => new lang_string('numdays', '', 120),
            90 => new lang_string('numdays', '', 90),
            60 => new lang_string('numdays', '', 60),
            30 => new lang_string('numdays', '', 30),
        ]
    ));

    $temp->add(new admin_setting_configselect('tempdatafoldercleanup', new lang_string('tempdatafoldercleanup', 'admin'),
        new lang_string('configtempdatafoldercleanup', 'admin'), 168,
        [
            1 => new lang_string('numhours', '', 1),
            3 => new lang_string('numhours', '', 3),
            6 => new lang_string('numhours', '', 6),
            9 => new lang_string('numhours', '', 9),
            12 => new lang_string('numhours', '', 12),
            18 => new lang_string('numhours', '', 18),
            24 => new lang_string('numhours', '', 24),
            48 => new lang_string('numdays', '', 2),
            168 => new lang_string('numdays', '', 7),
        ]
    ));

    $temp->add(new admin_setting_configduration(
        'xapicleanupperiod',
        new lang_string('xapicleanupperiod', 'xapi'),
        new lang_string('xapicleanupperiod_help', 'xapi'),
        WEEKSECS * 8,
        WEEKSECS
    ));

    $ADMIN->add('server', $temp);

    $temp->add(new admin_setting_configduration('filescleanupperiod',
        new lang_string('filescleanupperiod', 'admin'),
        new lang_string('filescleanupperiod_help', 'admin'),
        86400));

    // Environment.
    $ADMIN->add('server', new admin_externalpage('environment', new lang_string('environment', 'admin'),
        "{$CFG->wwwroot}/{$CFG->admin}/environment.php"));

    // PHP info.
    $ADMIN->add('server', new admin_externalpage('phpinfo', new lang_string('phpinfo'),
        "{$CFG->wwwroot}/{$CFG->admin}/phpinfo.php"));

    // Test outgoing mail configuration (hidden, accessed via direct link from the settings page).
    $ADMIN->add('server', new admin_externalpage('testoutgoingmailconf', new lang_string('testoutgoingmailconf', 'admin'),
        new moodle_url('/admin/testoutgoingmailconf.php'), 'moodle/site:config', true));

    // Performance.
    $temp = new admin_settingpage('performance', new lang_string('performance', 'admin'));

    // Memory limit options for large administration tasks.
    $memoryoptions = [
        '64M' => '64M',
        '128M' => '128M',
        '256M' => '256M',
        '512M' => '512M',
        '1024M' => '1024M',
        '2048M' => '2048M',
    ];

    // Allow larger memory usage for 64-bit sites only.
    if (PHP_INT_SIZE === 8) {
        $memoryoptions['3072M'] = '3072M';
        $memoryoptions['4096M'] = '4096M';
    }

    $temp->add(new admin_setting_configselect('extramemorylimit', new lang_string('extramemorylimit', 'admin'),
        new lang_string('configextramemorylimit', 'admin'), '512M', $memoryoptions));

    $temp->add(new admin_setting_configtext('maxtimelimit', new lang_string('maxtimelimit', 'admin'),
        new lang_string('maxtimelimit_desc', 'admin'), 0, PARAM_INT));

    $temp->add(new admin_setting_configtext('curlcache', new lang_string('curlcache', 'admin'),
        new lang_string('configcurlcache', 'admin'), 120, PARAM_INT));

    $temp->add(new admin_setting_configtext('curltimeoutkbitrate', new lang_string('curltimeoutkbitrate', 'admin'),
        new lang_string('curltimeoutkbitrate_help', 'admin'), 56, PARAM_INT));

    $ADMIN->add('server', $temp);

    // Tasks.
    $ADMIN->add('server', new admin_category('taskconfig', new lang_string('taskadmintitle', 'admin')));

    // Task processing.
    $temp = new admin_settingpage('taskprocessing', new lang_string('taskprocessing', 'admin'));

    $setting = new admin_setting_configcheckbox(
        'cron_enabled',
        new lang_string('cron_enabled', 'admin'),
        new lang_string('cron_enabled_desc', 'admin'),
        1
    );
    $setting->set_updatedcallback('theme_reset_static_caches');
    $temp->add($setting);

    $setting = new admin_setting_configduration(
        'cron_keepalive',
        new lang_string('cron_keepalive', 'admin'),
        new lang_string('cron_keepalive_desc', 'admin'),
        \core\cron::DEFAULT_MAIN_PROCESS_KEEPALIVE,
        // The default unit is minutes.
        MINSECS,
    );

    // Set an upper limit.
    $setting->set_max_duration(\core\cron::MAX_MAIN_PROCESS_KEEPALIVE);

    $temp->add($setting);

    $temp->add(
        new admin_setting_configtext(
            'task_scheduled_concurrency_limit',
            new lang_string('task_scheduled_concurrency_limit', 'admin'),
            new lang_string('task_scheduled_concurrency_limit_desc', 'admin'),
            3,
            PARAM_INT
        )
    );

    $temp->add(
        new admin_setting_configduration(
            'task_scheduled_max_runtime',
            new lang_string('task_scheduled_max_runtime', 'admin'),
            new lang_string('task_scheduled_max_runtime_desc', 'admin'),
            30 * MINSECS
        )
    );

    $temp->add(
        new admin_setting_configtext(
            'task_adhoc_concurrency_limit',
            new lang_string('task_adhoc_concurrency_limit', 'admin'),
            new lang_string('task_adhoc_concurrency_limit_desc', 'admin'),
            3,
            PARAM_INT
        )
    );

    $temp->add(
        new admin_setting_configduration(
            'task_adhoc_max_runtime',
            new lang_string('task_adhoc_max_runtime', 'admin'),
            new lang_string('task_adhoc_max_runtime_desc', 'admin'),
            30 * MINSECS
        )
    );

    $temp->add(
        new admin_setting_configduration(
            'task_adhoc_failed_retention',
            new lang_string('task_adhoc_failed_retention', 'admin'),
            new lang_string('task_adhoc_failed_retention_desc', 'admin'),
            \core\task\manager::ADHOC_TASK_FAILED_RETENTION,
            WEEKSECS
        )
    );

    $ADMIN->add('taskconfig', $temp);

    // Task log configuration.
    $temp = new admin_settingpage('tasklogging', new lang_string('tasklogging', 'admin'));
    $temp->add(
        new admin_setting_configselect(
            'task_logmode',
            new lang_string('task_logmode', 'admin'),
            new lang_string('task_logmode_desc', 'admin'),
            \core\task\logmanager::MODE_ALL,
            [
                \core\task\logmanager::MODE_ALL => new lang_string('task_logmode_all', 'admin'),
                \core\task\logmanager::MODE_FAILONLY => new lang_string('task_logmode_failonly', 'admin'),
                \core\task\logmanager::MODE_NONE => new lang_string('task_logmode_none', 'admin'),
            ]
        )
    );
    $temp->add(
        new admin_setting_configcheckbox(
            'task_logtostdout',
            new lang_string('task_logtostdout', 'admin'),
            new lang_string('task_logtostdout_desc', 'admin'),
            1
        )
    );

    if (\core\task\logmanager::uses_standard_settings()) {
        $temp->add(
            new admin_setting_configduration(
                'task_logretention',
                new \lang_string('task_logretention', 'admin'),
                new \lang_string('task_logretention_desc', 'admin'),
                28 * DAYSECS
            )
        );

        $temp->add(
            new admin_setting_configtext(
                'task_logretainruns',
                new \lang_string('task_logretainruns', 'admin'),
                new \lang_string('task_logretainruns_desc', 'admin'),
                20,
                PARAM_INT
            )
        );
    }
    $ADMIN->add('taskconfig', $temp);

    // Task logs.
    if (\core\task\logmanager::uses_standard_settings()) {
        $ADMIN->add('taskconfig', new admin_externalpage(
            'tasklogs',
            new lang_string('tasklogs', 'admin'),
            "{$CFG->wwwroot}/{$CFG->admin}/tasklogs.php"
        ));
    }

    // Email.
    $ADMIN->add('server', new admin_category('email', new lang_string('categoryemail', 'admin')));

    // Outgoing mail configuration.
    $temp = new admin_settingpage('outgoingmailconfig', new lang_string('outgoingmailconfig', 'admin'));

    if (!empty($CFG->noemailever)) {
        $noemaileverwarning = new \core\output\notification(get_string('noemaileverwarning', 'admin'),
        \core\output\notification::NOTIFY_ERROR);
        $temp->add(new admin_setting_heading('outgoingmaildisabled', '', $OUTPUT->render($noemaileverwarning)));
    }

    $temp->add(new admin_setting_heading('smtpheading', new lang_string('smtp', 'admin'),
        new lang_string('smtpdetail', 'admin')));

    $temp->add(new admin_setting_configtext('smtphosts', new lang_string('smtphosts', 'admin'),
        new lang_string('configsmtphosts', 'admin'), '', PARAM_RAW));

    $options = [
        '' => new lang_string('none', 'admin'),
        'ssl' => 'SSL',
        'tls' => 'TLS',
    ];

    $temp->add(new admin_setting_configselect('smtpsecure', new lang_string('smtpsecure', 'admin'),
        new lang_string('configsmtpsecure', 'admin'), '', $options));

    $authtypeoptions = [
        'LOGIN' => 'LOGIN',
        'PLAIN' => 'PLAIN',
        'NTLM' => 'NTLM',
        'CRAM-MD5' => 'CRAM-MD5',
    ];

    // Get all the issuers.
    $issuers = \core\oauth2\api::get_all_issuers();
    $enabledissuers = [];
    foreach ($issuers as $issuer) {
        // Get the enabled issuer only.
        if ($issuer->get('enabled')) {
            $enabledissuers[] = $issuer;
        }
    }

    if (count($enabledissuers) > 0) {
        $authtypeoptions['XOAUTH2'] = 'XOAUTH2';
    }

    $temp->add(new admin_setting_configselect('smtpauthtype', new lang_string('smtpauthtype', 'admin'),
        new lang_string('configsmtpauthtype', 'admin'), 'LOGIN', $authtypeoptions));

    if (count($enabledissuers) > 0) {
        $oauth2services = [
            '' => new lang_string('none', 'admin'),
        ];
        foreach ($enabledissuers as $issuer) {
            $oauth2services[$issuer->get('id')] = s($issuer->get('name'));
        }

        $temp->add(new admin_setting_configselect('smtpoauthservice', new lang_string('issuer', 'auth_oauth2'),
            new lang_string('configsmtpoauthservice', 'admin'), '', $oauth2services));
    }

    $temp->add(new admin_setting_configtext('smtpuser', new lang_string('smtpuser', 'admin'),
        new lang_string('configsmtpuser', 'admin'), '', PARAM_NOTAGS));

    $temp->add(new admin_setting_configpasswordunmask('smtppass', new lang_string('smtppass', 'admin'),
        new lang_string('configsmtpuser', 'admin'), ''));

    $temp->add(new admin_setting_configtext('smtpmaxbulk', new lang_string('smtpmaxbulk', 'admin'),
        new lang_string('configsmtpmaxbulk', 'admin'), 1, PARAM_INT));

    $temp->add(new admin_setting_heading('noreplydomainheading', new lang_string('noreplydomain', 'admin'),
        new lang_string('noreplydomaindetail', 'admin')));

    $default = clean_param('noreply@' . get_host_from_url($CFG->wwwroot), PARAM_EMAIL);
    if (!$default) {
        $default = null;
    }
    $temp->add(new admin_setting_configtext('noreplyaddress', new lang_string('noreplyaddress', 'admin'),
        new lang_string('confignoreplyaddress', 'admin'), $default, PARAM_EMAIL));

    $temp->add(new admin_setting_configtextarea('allowedemaildomains',
        new lang_string('allowedemaildomains', 'admin'),
        new lang_string('configallowedemaildomains', 'admin'),
        ''));

    $temp->add(new admin_setting_heading('divertallemailsheading', new lang_string('divertallemails', 'admin'),
        new lang_string('divertallemailsdetail', 'admin')));
    $temp->add(new admin_setting_configtext('divertallemailsto',
        new lang_string('divertallemailsto', 'admin'),
        new lang_string('divertallemailsto_desc', 'admin'),
        ''));
    $temp->add(new admin_setting_configtextarea('divertallemailsexcept',
        new lang_string('divertallemailsexcept', 'admin'),
        new lang_string('divertallemailsexcept_desc', 'admin'),
        '', PARAM_RAW, '50', '4'));

    $noreplyaddress = isset($CFG->noreplyaddress) ? $CFG->noreplyaddress : 'noreply@example.com';
    $dkimdomain = substr(strrchr($noreplyaddress, "@"), 1);
    $dkimselector = empty($CFG->emaildkimselector) ? '[selector]' : $CFG->emaildkimselector;
    $pempath = "\$CFG->dataroot/dkim/{$dkimdomain}/{$dkimselector}.private";
    $temp->add(new admin_setting_heading('emaildkim', new lang_string('emaildkim', 'admin'),
        new lang_string('emaildkiminfo', 'admin', ['path' => $pempath, 'docs' => \get_docs_url('Mail_configuration#DKIM')])));
    $temp->add(new admin_setting_configtext('emaildkimselector', new lang_string('emaildkimselector', 'admin'),
        new lang_string('configemaildkimselector', 'admin'), '', PARAM_FILE));

    $url = new moodle_url('/admin/testoutgoingmailconf.php');
    $link = html_writer::link($url, get_string('testoutgoingmailconf', 'admin'));
    $temp->add(new admin_setting_heading('testoutgoinmailc', new lang_string('testoutgoingmailconf', 'admin'),
        new lang_string('testoutgoingmaildetail', 'admin', $link)));

    $temp->add(new admin_setting_heading('emaildoesnotfit', new lang_string('doesnotfit', 'admin'),
        new lang_string('doesnotfitdetail', 'admin')));

    $charsets = get_list_of_charsets();
    unset($charsets['UTF-8']);
    $options = [
        '0' => 'UTF-8',
    ];
    $options = array_merge($options, $charsets);
    $temp->add(new admin_setting_configselect('sitemailcharset', new lang_string('sitemailcharset', 'admin'),
        new lang_string('configsitemailcharset', 'admin'), '0', $options));

    $temp->add(new admin_setting_configcheckbox('allowusermailcharset', new lang_string('allowusermailcharset', 'admin'),
        new lang_string('configallowusermailcharset', 'admin'), 0));

    $temp->add(new admin_setting_configcheckbox('allowattachments', new lang_string('allowattachments', 'admin'),
        new lang_string('configallowattachments', 'admin'), 1));

    $options = [
        'LF' => 'LF',
        'CRLF' => 'CRLF',
    ];
    $temp->add(new admin_setting_configselect('mailnewline', new lang_string('mailnewline', 'admin'),
        new lang_string('configmailnewline', 'admin'), 'LF', $options));

    $choices = [
        new lang_string('never', 'admin'),
        new lang_string('always', 'admin'),
        new lang_string('onlynoreply', 'admin'),
    ];
    $temp->add(new admin_setting_configselect('emailfromvia', new lang_string('emailfromvia', 'admin'),
        new lang_string('configemailfromvia', 'admin'), 1, $choices));

    $temp->add(new admin_setting_configtext('emailsubjectprefix', new lang_string('emailsubjectprefix', 'admin'),
        new lang_string('configemailsubjectprefix', 'admin'), '', PARAM_RAW));

    $temp->add(new admin_setting_configtextarea('emailheaders', new lang_string('emailheaders', 'admin'),
        new lang_string('configemailheaders', 'admin'), '', PARAM_RAW, '50', '3'));

    $ADMIN->add('email', $temp);

    // Update notifications.
    if (empty($CFG->disableupdatenotifications)) {
        $temp = new admin_settingpage('updatenotifications', new lang_string('updatenotifications', 'core_admin'));
        $temp->add(new admin_setting_configcheckbox('updateautocheck', new lang_string('updateautocheck', 'core_admin'),
            new lang_string('updateautocheck_desc', 'core_admin'), 1));
        $temp->add(new admin_setting_configselect('updateminmaturity', new lang_string('updateminmaturity', 'core_admin'),
            new lang_string('updateminmaturity_desc', 'core_admin'), MATURITY_STABLE,
            [
                MATURITY_ALPHA => new lang_string('maturity'.MATURITY_ALPHA, 'core_admin'),
                MATURITY_BETA => new lang_string('maturity'.MATURITY_BETA, 'core_admin'),
                MATURITY_RC => new lang_string('maturity'.MATURITY_RC, 'core_admin'),
                MATURITY_STABLE => new lang_string('maturity'.MATURITY_STABLE, 'core_admin'),
            ]
        ));
        $temp->add(new admin_setting_configcheckbox('updatenotifybuilds', new lang_string('updatenotifybuilds', 'core_admin'),
            new lang_string('updatenotifybuilds_desc', 'core_admin'), 0));
        $ADMIN->add('server', $temp);
    }

    // Web services.
    $ADMIN->add('server', new admin_category('webservicesettings', new lang_string('webservices', 'webservice')));

    // Web services > Overview.
    $temp = new admin_settingpage('webservicesoverview', new lang_string('webservicesoverview', 'webservice'));
    $temp->add(new admin_setting_webservicesoverview());
    $ADMIN->add('webservicesettings', $temp);

    // Web services > API documentation.
    $ADMIN->add('webservicesettings', new admin_externalpage('webservicedocumentation', new lang_string('wsdocapi', 'webservice'),
        "{$CFG->wwwroot}/{$CFG->admin}/webservice/documentation.php", 'moodle/site:config', false));

    // Web services > External services.
    $temp = new admin_settingpage('externalservices', new lang_string('externalservices', 'webservice'));

    $temp->add(new admin_setting_heading('manageserviceshelpexplaination', new lang_string('information', 'webservice'),
        new lang_string('servicehelpexplanation', 'webservice')));

    $temp->add(new admin_setting_manageexternalservices());

    $ADMIN->add('webservicesettings', $temp);

    $ADMIN->add('webservicesettings', new admin_externalpage('externalservice', new lang_string('editaservice', 'webservice'),
        "{$CFG->wwwroot}/{$CFG->admin}/webservice/service.php", 'moodle/site:config', true));

    $ADMIN->add('webservicesettings', new admin_externalpage('externalservicefunctions',
        new lang_string('externalservicefunctions', 'webservice'), "{$CFG->wwwroot}/{$CFG->admin}/webservice/service_functions.php",
        'moodle/site:config', true));

    $ADMIN->add('webservicesettings', new admin_externalpage('externalserviceusers',
        new lang_string('externalserviceusers', 'webservice'), "{$CFG->wwwroot}/{$CFG->admin}/webservice/service_users.php",
        'moodle/site:config', true));

    $ADMIN->add('webservicesettings', new admin_externalpage('externalserviceusersettings',
        new lang_string('serviceusersettings', 'webservice'), "{$CFG->wwwroot}/{$CFG->admin}/webservice/service_user_settings.php",
        'moodle/site:config', true));

    // Web services > Manage protocols.
    $temp = new admin_settingpage('webserviceprotocols', new lang_string('manageprotocols', 'webservice'));
    $temp->add(new admin_setting_managewebserviceprotocols());
    if (empty($CFG->enablewebservices)) {
        $temp->add(new admin_setting_heading('webservicesaredisabled', '', new lang_string('disabledwarning', 'webservice')));
    }

    // We cannot use $OUTPUT->doc_link() this early, we would lose the ability to set the page layout on all admin pages.
    $url = new moodle_url(get_docs_url('How_to_get_a_security_key'));
    $wsdoclink = html_writer::link($url, new lang_string('supplyinfo', 'webservice'), ['target' => '_blank']);
    $temp->add(new admin_setting_configcheckbox('enablewsdocumentation', new lang_string('enablewsdocumentation', 'admin'),
        new lang_string('configenablewsdocumentation', 'admin', $wsdoclink), false));

    $ADMIN->add('webservicesettings', $temp);

    $plugins = core_plugin_manager::instance()->get_plugins_of_type('webservice');
    core_collator::asort_objects_by_property($plugins, 'displayname');
    foreach ($plugins as $plugin) {
        /** @var \core\plugininfo\webservice $plugin */
        $plugin->load_settings($ADMIN, 'webservicesettings', $hassiteconfig);
    }

    // Web services > Manage tokens.
    $ADMIN->add('webservicesettings', new admin_externalpage('webservicetokens', new lang_string('managetokens', 'webservice'),
        new moodle_url('/admin/webservice/tokens.php')));
}