CustomShippingEstimate.php

<?php
/**
 * Plugin Name: Custom Shipping Estimate for WooCommerce
 * Description: Adds a shipping estimate notice on WooCommerce product pages.
 * Version: 1.0
 * Author: trueqap
 */

if ( ! defined( 'ABSPATH' ) ) {
    exit; 
}

function add_custom_shipping_estimate() {
    date_default_timezone_set('Europe/Budapest');

    $today = new DateTime();
    $today->setTime(0, 0, 0);
    $shipping_date = clone $today;

    $business_days_added = 0;
    while ($business_days_added < 2) {
        $shipping_date->modify('+1 day');
        if (!in_array($shipping_date->format('N'), [6, 7])) {
            $business_days_added++;
        }
    }

    echo 'A várható szállítási idő: ' . $shipping_date->format('Y-m-d');
}

add_action('woocommerce_before_add_to_cart_form', 'add_custom_shipping_estimate');