Add SKU to product permalinks

<?php

/*
Plugin Name: Add SKU to Product Permalinks
Plugin URI: http://maciejbis.net
Description: A plugin that adjusts the functionality of this website
Version: 1.0
Author: Maciej Bis
Author URI: http://www.maciejbis.net
License: GPL2
*/

define('SKU_FIELD', '_sku');

function pm_sku_in_woo_permalinks($url, $post) {
    global $permalink_manager_uris;

    if(!empty($post->post_type) && ($post->post_type == 'product') && ($post->post_status == 'publish')) {
        $product_sku = get_post_meta($post->ID, SKU_FIELD, true);

        if(!empty($product_sku)) {
            $product_sku = sanitize_title($product_sku);

            $url = trim(get_option('home'), '/') . "/shop/{$product_sku}";
            $url = user_trailingslashit($url);
        }
    }

    return $url;
}
add_filter('post_type_link', 'pm_sku_in_woo_permalinks', 999, 2);

function pm_detect_sku_woo_permalinks($query) {
    global $wpdb, $pm_query, $wp;

    // Do not run when Elementor is opened
    if((!empty($_REQUEST['action']) && strpos($_REQUEST['action'], 'elementor') !== false) || isset($_REQUEST['elementor-preview'])) {
        return $query;
    }

    if(!empty($wp->request) && strpos($wp->request, 'shop/') !== false) {
        $sku_number = basename($wp->request);

        // 2. Check if the slug is assigned to any post item
        $sql_query = $wpdb->prepare("SELECT p.* FROM {$wpdb->posts} AS p JOIN {$wpdb->postmeta} AS pm ON pm.post_id = p.ID AND pm.meta_key = %s WHERE 1=1 AND meta_value = %s AND post_type = %s AND post_status = 'publish'", array(SKU_FIELD, $sku_number, 'product'));
        $post = $wpdb->get_row($sql_query);

        // 3. Filter the query if post was found
        if(!empty($post->post_name)) {
            // $page = (!empty($query['page'])) ? $query['page'] : 1;
            $new_query = array(
                'post_type' => $post->post_type,
                $post->post_type => $post->post_name,
                'name' => $post->post_name,
                // 'page' => $page,
                'do_not_redirect' => 1,
            );

            // 4. Disable canonical redirect
            remove_action('template_redirect', 'wp_old_slug_redirect');
            remove_action('template_redirect', 'redirect_canonical');
            add_filter('wpml_is_redirected', '__return_false', 99, 2);
            add_filter('pll_check_canonical_url', '__return_false', 99, 2);

            return $new_query;
        }
    }

    return $query;
}
add_filter('request', 'pm_detect_sku_woo_permalinks', 9999);