SKU WooCommerce Permalinks

<?php

/**
 * Change permalink for WooCommerce product based on SKU and product name.
 *
 * @param string $url The generated permalink URL.
 * @param WP_Post $post The post object.
 * @return string The modified permalink URL.
 */
function pm_sku_permalinks( $url, $post ) {
    if ( $post->post_type !== 'product' || $post->post_status !== 'publish' ) {
        return $url;
    }

    $product_sku  = get_post_meta( $post->ID, SKU_FIELD, true );
    $product_name = $post->post_name;

    if ( empty( $product_sku ) || empty( $product_name ) ) {
        return $url;
    }

    $url = sprintf( "%s/%s/%s", get_home_url(), sanitize_title( $product_sku ), sanitize_title( $product_name ) );

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

/**
 * Detect WooCommerce product based on SKU and product name in the permalink.
 *
 * @param array $query The current query variables.
 *
 * @return array The modified query variables.
 */
function pm_detect_sku_product_permalinks( $query ) {
    global $wpdb, $wp;

    // Do not run when Elementor is active
    if ( defined( 'ELEMENTOR_PATH' ) || isset( $_REQUEST['elementor-preview'] ) ) {
        return $query;
    }

    $request_path = trim( $wp->request, '/' );

    // Check if the request path matches the expected pattern
    if ( preg_match( '/^([^\/]+)\/([^\/]+)$/', $request_path, $matches ) ) {
        $sku_number   = $matches[1];
        $product_name = $matches[2];

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

        $product_id = $wpdb->get_var( $sql_query );

        // If product found, set query variables accordingly
        if ( $product_id && get_post_field( 'post_name', $product_id ) === $product_name ) {
            $query['post_type']       = 'product';
            $query['name']            = $product_name;
            $query['do_not_redirect'] = 1;

            // Disable canonical redirect
            remove_action( 'template_redirect', 'wp_old_slug_redirect' );
            remove_action( 'template_redirect', 'redirect_canonical' );
        }
    }

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