public Invoice issuance(InvoiceRequest invoiceRequest, TaxPolicy taxPolicy) {
Invoice invoice = invoiceFactory.create(invoiceRequest.getClientData());
for (RequestItem item : invoiceRequest.getItems()) {
Money net = item.getTotalCost();
Tax tax = taxPolicy.calculateTax(item.getProductData().getType(), net);
InvoiceLine invoiceLine =
new InvoiceLine(item.getProductData(), item.getQuantity(), net, tax);
invoice.addItem(invoiceLine);
}
return invoice;
}
