settings.php

<?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/>.

/**
 * Adds admin settings for the plugin.
 *
 * @package     local_booking
 * @category    admin
 * @copyright   2021 Mustafa Hajjar
 * @license     https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

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

require_once($CFG->dirroot . '/local/booking/lib.php');

if ($hassiteconfig) {
    $ADMIN->add('localplugins', new admin_category('local_booking_settings', new lang_string('pluginname', 'local_booking')));
    $settingspage = new admin_settingpage('managelocalbooking', new lang_string('pluginname', 'local_booking'));

    if ($ADMIN->fulltree) {
        // add general settings section
        $settingspage->add(new admin_setting_heading('local_booking_addheading_ato', new lang_string('atosection', 'local_booking'),''));

        // ATO name, website, email, and url
        $settingspage->add(new admin_setting_configtext('local_booking/atoname', new lang_string('atoname', 'local_booking'), null, null, PARAM_RAW, 50));

        // add general settings section
        $settingspage->add(new admin_setting_heading('local_booking_addheading_posting', new lang_string('postingsection', 'local_booking'),''));

        // hours in the day 24-hour format
        $options = array();
        for ($i = 0; $i <= 23; $i++) {
            $options[] = substr('00'. $i, -2).':00';
        }
        // first allowable session time
        $settingspage->add(new admin_setting_configselect('local_booking/firstsession',
            new lang_string('firstsession', 'local_booking'), new lang_string('firstsessiondesc', 'local_booking'),
            8, $options)
        );
        // last allowable session time
        $settingspage->add(new admin_setting_configselect('local_booking/lastsession',
            new lang_string('lastsession', 'local_booking'), new lang_string('lastsessiondesc', 'local_booking'),
            23, $options)
        );

        // availability recording weeks ahead
        $settingspage->add(new admin_setting_configtext('local_booking/weeksahead',
            new lang_string('weeksahead', 'local_booking'), new lang_string('weeksaheaddesc', 'local_booking'),
            5, PARAM_INT)
        );

        // add prioritization settings section
        $settingspage->add(new admin_setting_heading('local_booking_addheading_priority', new lang_string('prioritizationsection', 'local_booking'),''));

        // last session recency days weight multiplier
        $settingspage->add(new admin_setting_configtext('local_booking/recencydaysweight',
            new lang_string('recencydaysweight', 'local_booking'), new lang_string('recencydaysweightdesc', 'local_booking'),
            10, PARAM_INT)
        );

        // slot count weight multiplier
        $settingspage->add(new admin_setting_configtext('local_booking/slotcountweight',
            new lang_string('slotcountweight', 'local_booking'), new lang_string('slotcountweightdesc', 'local_booking'),
            50, PARAM_INT)
        );

        // activity count weight multiplier
        $settingspage->add(new admin_setting_configtext('local_booking/activitycountweight',
            new lang_string('activitycountweight', 'local_booking'), new lang_string('activitycountweightdesc', 'local_booking'),
            1, PARAM_INT)
        );

        // lesson completion weight multiplier
        $settingspage->add(new admin_setting_configtext('local_booking/completionweight',
            new lang_string('completionweight', 'local_booking'), new lang_string('completionweightdesc', 'local_booking'),
            10, PARAM_INT)
        );

        // add plugin configurations settings section
        $settingspage->add(new admin_setting_heading('local_booking_addheading_configs', new lang_string('pluginconfigssection', 'local_booking'),''));

        // lesson completion weight multiplier
        $settingspage->add(new admin_setting_configtextarea('local_booking/configsjson',
            new lang_string('configsjson', 'local_booking'), new lang_string('configsjsondesc', 'local_booking'), null)
        );
    }

    $ADMIN->add('localplugins', $settingspage);
}