utm origem

utm.php

function wp_set_origin_cookie() {
    $cookie_value = $_SERVER['HTTP_REFERER'];

    if ( ! is_admin() && ! isset( $_COOKIE['origin'] ) ) {
        setcookie( 'origin', $cookie_value, time() + 3600*24*30, COOKIEPATH, COOKIE_DOMAIN, false );
    }
}
add_action( 'init', 'wp_set_origin_cookie');

function wp_add_order_referrer( $order ) {
    $order->add_meta_data( 'referrer', $_COOKIE['origin'] );
}
add_action('woocommerce_checkout_create_order', 'wp_add_order_referrer', 10, 1 );