custom discount with php

Hello,

I’m using a custom php function to add a 10% discount on cart when people select the local pickup shipping method.

Any help on how to display it on the invoice ?

Thanks !

Alexis

here is the function :

add_action( 'woocommerce_cart_calculate_fees', 'custom_discount_for_pickup_shipping_method', 10, 1 );
function custom_discount_for_pickup_shipping_method( $cart ) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;

    $percentage = 10; // <=== Discount percentage

    $chosen_shipping_method_id = WC()->session->get( 'chosen_shipping_methods' )[0];
    $chosen_shipping_method    = explode(':', $chosen_shipping_method_id)[0];

    // Only for Local pickup chosen shipping method
    if ( strpos( $chosen_shipping_method_id, 'local_pickup' ) !== false ) {
        // Calculate the discount
        $discount = $cart->get_subtotal() * $percentage / 100;
        // Add the discount
        $cart->add_fee( __('Réduction Clique & Collecte') . ' (' . $percentage . '%)', -$discount );
    }
}