Dostosowania WooCommerce

<?php

// Fill missing postcode and city
add_action('woocommerce_new_order', function (int $orderId) {
    $order = wc_get_order($orderId);
    if ( ! $order->get_billing_postcode()) {
        $order->set_billing_postcode('00-000');
    }
    if ( ! $order->get_billing_city()) {
        $order->set_billing_city(__('Produkt Wirtualny'));
    }
    $order->set_billing_country('PL');
    $order->save();
});

// Reconfigure checkout fields
add_filter('woocommerce_checkout_fields', function (array $fields) {
    $fields['billing']['billing_first_name']['priority'] = 1;
    $fields['billing']['billing_last_name']['priority']  = 2;
    $fields['billing']['billing_email']['priority']      = 3;
    $fields['billing']['billing_phone']['priority']      = 4;
    $fields['billing']['billing_faktura']['priority']    = 5;
    $fields['billing']['billing_company']['priority']    = 6;
    $fields['billing']['billing_company']['required']    = false;
    $fields['billing']['billing_nip']['priority']        = 7;
    $fields['billing']['billing_address_1']['priority']  = 8;
    $fields['billing']['billing_address_1']['required']  = false;
    $fields['billing']['billing_address_2']['priority']  = 9;
    $fields['billing']['billing_address_2']['required']  = false;
    $fields['billing']['billing_postcode']['priority']   = 10;
    $fields['billing']['billing_postcode']['required']   = false;
    $fields['billing']['billing_postcode']['validate']   = [];
    $fields['billing']['billing_city']['priority']       = 11;
    $fields['billing']['billing_city']['required']       = false;
    unset($fields['billing']['billing_state']);
    unset($fields['order']['order_comments']);

    return $fields;
});

// Add NIP field validation
add_action('woocommerce_after_checkout_validation', function (array $data, WP_Error $errors) {
    $isValidNip = function (string $nip): bool {
        $nip = str_replace('-', '', $nip);

        if ( ! preg_match('/^\d{10}$/', $nip)) {
            return false;
        }

        $checksum = 6 * (int)$nip[0] +
                    5 * (int)$nip[1] +
                    7 * (int)$nip[2] +
                    2 * (int)$nip[3] +
                    3 * (int)$nip[4] +
                    4 * (int)$nip[5] +
                    5 * (int)$nip[6] +
                    6 * (int)$nip[7] +
                    7 * (int)$nip[8];

        return (int)$nip[9] === $checksum % 11;
    };

    $nip = $data['billing_nip'] ?? '';
    if ($nip && ! $isValidNip($nip)) {
        $errors->add('invalid_nip', __('Nieprawidłowy NIP.'));
    }
}, 10, 2);