core/src/Payment/Pipelines/Cart/ApplyCashOnDeliveryFee.php

<?php

namespace Modules\Core\Payment\Pipelines\Cart;

use Closure;
use Lunar\DataTypes\Price;
use Lunar\Models\Contracts\Cart as CartContract;
use Modules\Core\Payment\Models\PaymentMethod;

final class ApplyCashOnDeliveryFee
{
    /**
     * Called just before cart totals are calculated.
     *
     * @param  Closure(CartContract): mixed  $next
     */
    public function handle(CartContract $cart, Closure $next): mixed
    {
        if (($cart->meta['payment_method'] ?? null) === 'cash-on-delivery') {
            $fee = (int) (PaymentMethod::where('type', 'cash-on-delivery')->value('data->fee') ?? 0);

            $cart->shippingTotal = new Price(
                ($cart->shippingTotal?->value ?? 0) + $fee,
                $cart->currency,
                1
            );
        }

        return $next($cart);
    }
}