AdventureWorks.UILogic.ViewModels.ShoppingCartPageViewModel.ResolveNavigationActionAsync C# (CSharp) Метод

        private async Task<Action> ResolveNavigationActionAsync()
        {
            Action navigateAction = null;
            var navigationServiceReference = _navigationService;

            // Retrieve the default information for the Order
            var defaultShippingAddress = await _checkoutDataRepository.GetDefaultShippingAddressAsync();
            var defaultBillingAddress = await _checkoutDataRepository.GetDefaultBillingAddressAsync();
            var defaultPaymentMethod = await _checkoutDataRepository.GetDefaultPaymentMethodAsync();

            if (defaultShippingAddress == null || defaultBillingAddress == null || defaultPaymentMethod == null)
            {
                // Navigate to the CheckoutHubPage to fill the missing default information
                navigateAction = () => navigationServiceReference.Navigate("CheckoutHub", null);
            }
            else
            {
                // Create the Order with the current information. Then navigate to the CheckoutSummaryPage
                var shoppingCartReference = _shoppingCart;
                var orderRepositoryReference = _orderRepository;
                var accountServiceReference = _accountService;
                navigateAction = async () =>
                    {
                        var user = accountServiceReference.SignedInUser;
                        await orderRepositoryReference.CreateBasicOrderAsync(user.UserName, 
                                                                             shoppingCartReference,
                                                                             defaultShippingAddress,
                                                                             defaultBillingAddress,
                                                                             defaultPaymentMethod);

                        navigationServiceReference.Navigate("CheckoutSummary", null);
                    };
            }

            return navigateAction;
        }