Bedrock multisite

<?php
/**
 * Plugin Name: Multisite URL Fixer
 * Plugin URI: https://github.com/roots/bedrock/
 * Description: Fixes WordPress issues with home and site URL on multisite.
 * Version: 1.0.0
 * Author: Roots
 * Author URI: https://roots.io/
 * License: MIT License
 */

namespace Roots\Bedrock;

if ( ! is_multisite() ) {
    return;
}

/**
 * Class URLFixer
 * @package Roots\Bedrock
 * @author Roots
 * @link https://roots.io/
 */
class URLFixer {
    /** @var Roots\Bedrock\URLFixer Singleton instance */
    private static $instance = null;

    /**
     * Singleton.
     *
     * @return Roots\Bedrock\URLFixer
     */
    public static function instance() {
        if ( null === self::$instance )
            self::$instance = new self();

        return self::$instance;
    }

    /**
     * Add filters to verify / fix URLs.
     */
    public function add_filters() {
        add_filter( 'option_home', array( $this, 'fix_home_url' ) );
        add_filter( 'option_siteurl', array( $this, 'fix_site_url' ) );
        add_filter( 'network_site_url', array( $this, 'fix_network_site_url' ), 10, 3 );
    }

    /**
     * Ensure that home URL does not contain the /wp subdirectory.
     *
     * @param string $value the unchecked home URL
     * @return string the verified home URL
     */
    public function fix_home_url( $value ) {
        if ( '/wp' === substr( $value, -3 ) ) {
            $value = substr( $value, 0, -3 );
        }
        return $value;
    }

    /**
     * Ensure that site URL contains the /wp subdirectory.
     *
     * @param string $value the unchecked site URL
     * @return string the verified site URL
     */
    public function fix_site_url( $value ) {
        if ( '/wp' !== substr( $value, -3 ) ) {
            $value .= '/wp';
        }
        return $value;
    }

    /**
     * Ensure that the network site URL contains the /wp subdirectory.
     *
     * @param string $url    the unchecked network site URL with path appended
     * @param string $path   the path for the URL
     * @param string $scheme the URL scheme
     * @return string the verified network site URL
     */
    public function fix_network_site_url( $url, $path, $scheme ) {
        $path = ltrim( $path, '/' );
        $url = substr( $url, 0, strlen( $url ) - strlen( $path ) );

        if ( 'wp/' !== substr( $url, -3 ) ) {
            $url .= 'wp/';
        }

        return $url . $path;
    }
}

URLFixer::instance()->add_filters();

/**
 * Multi site
 */
#Config::define('WP_ALLOW_MULTISITE', true);
#Config::define('MULTISITE', true);
#Config::define('SUBDOMAIN_INSTALL', false); // Set to true if using subdomains
#Config::define('DOMAIN_CURRENT_SITE', env('DOMAIN_CURRENT_SITE'));
#Config::define('PATH_CURRENT_SITE', env('PATH_CURRENT_SITE') ?: '/');
#Config::define('SITE_ID_CURRENT_SITE', env('SITE_ID_CURRENT_SITE') ?: 1);
#Config::define('BLOG_ID_CURRENT_SITE', env('BLOG_ID_CURRENT_SITE') ?: 1);