using Grand.Business.Core.Queries.Checkout.Orders;
using Grand.Domain.Payments;
using MediatR;

namespace Grand.Business.Checkout.Queries.Handlers.Orders
{
    public class CanRefundOfflineQueryHandler : IRequestHandler<CanRefundOfflineQuery, bool>
    {
        public Task<bool> Handle(CanRefundOfflineQuery request, CancellationToken cancellationToken)
        {
            var paymentTransaction = request.PaymentTransaction;
            if (paymentTransaction == null)
                throw new ArgumentNullException(nameof(request.PaymentTransaction));

            if (paymentTransaction.TransactionAmount == 0)
                return Task.FromResult(false);

            //refund cannot be made if previously a partial refund has been already done. only other partial refund can be made in this case
            return paymentTransaction.RefundedAmount > 0 ? Task.FromResult(false) : Task.FromResult(paymentTransaction.TransactionStatus == TransactionStatus.Paid);
        }
    }
}
