Rewrite products permalinks + guess 404 permalinks

<?php

/*
Plugin Name: Rewrite 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
*/

/**
 * Parse requested URL
 */
function bis_parse_requested_url() {
    global $pm_query, $wp;

    if(empty($wp->request)) {
        return;
    }

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

    // Do not run if custom permalink was detected
    if(!empty($pm_query['id'])) {
        return;
    }

    // 1. Get the slug
    preg_match('/^\/?(?:product)(?:\/.*)?\/([^\/]+)\/([\d]+)$/', $wp->request, $parts);

    return $parts;
}

/**
 * Detect products permalinks
 */
function bis_detect_product_permalinks($query) {
    global $wpdb;

    $parts = bis_parse_requested_url();

    if(!empty($parts[2])) {
        // $slug = basename($parts[1]);
        $product_id = (int) $parts[2];
        $product = get_post($product_id);

        if(!empty($product)) {
            $new_query = array(
                'post_type' => 'product',
                'product' => $product->post_name,
                'name' => $product->post_name,
                // 'page' => $page,
                'do_not_redirect' => 1,
            );
        }

        // 3. Overwrite the query object & Disable canonical redirect
        if(!empty($new_query)) {
            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);

            $query = $new_query;
        }
    }

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

/**
 * Find a similar product
 */
function bis_guess_product() {
    global $wpdb;

    if(is_404()) {
        $parts = bis_parse_requested_url();

        if(!empty($parts[1])) {
            $product_slug = preg_replace('/([^-]+-)(.*)(-[^-]+)/', '$2', $parts[1]);
            $where = $wpdb->prepare('post_name LIKE %s', '%' . $wpdb->esc_like($product_slug) . '%');

            $product_id = $wpdb->get_var("SELECT ID FROM $wpdb->posts WHERE $where AND post_type = 'product' AND post_status = 'publish'");
            $product_permalink = get_permalink($product_id);

            if(!empty($product_permalink)) {
                wp_safe_redirect($product_permalink, 301, 'Bis');
                exit();
            }
        }
    }
}
add_action('template_redirect', 'bis_guess_product');

/**
 * Get taxonomy slug
 */
function bis_get_taxonomy_slug($post_id, $taxonomy) {
    $taxonomy_slug = '';

    // Get the custom taxonomy terms in use by this post.
    $terms = get_the_terms($post_id, $taxonomy);

    if(!empty($terms)) {
        $terms = wp_list_sort(
            $terms,
            array(
                'parent'  => 'DESC',
                'term_id' => 'ASC',
            )
        );

        if(!empty($terms[0])) {
            $taxonomy_slug = $terms[0]->slug;
        }
    }

    return $taxonomy_slug;
}

/**
 * Rewrite product permalinks
 */
function bis_filter_product_permalinks($url, $post, $leavename, $sample) {
    if(!empty($post->post_type) && ($post->post_type == 'product')) {
        $product_taxonomies = get_object_taxonomies($post);

        // New URL format
        $new_url = 'product/%store%/%product%/%product_id%';

        // A. Replace taxonomy slugs
        if($product_taxonomies) {
            foreach($product_taxonomies as $taxonomy) {
                // Check if taxonomy tag is present
                if(strpos($new_url, "%{$taxonomy}") === false) { continue; }

                $taxonomy_slug = bis_get_taxonomy_slug($post->ID, $taxonomy);

                $new_url = str_replace("%{$taxonomy}%", $taxonomy_slug, $new_url);
            }
        }

        // B. Replace product ID
        $new_url = str_replace("%product_id%", $post->ID, $new_url);

        // C. Replace product slug
        $new_url = str_replace("%product%", $post->post_name, $new_url);

        $url = sprintf('%s/%s', trim(get_option('home'), "/"), $new_url);
        $url = user_trailingslashit($url);
    }

    return $url;
}
add_filter('post_type_link', 'bis_filter_product_permalinks', 10, 4);