// Create a paymentsRequest
using Adyen;
using Adyen.Model.Checkout;
using Adyen.Service;
using Environment = Adyen.Model.Enum.Environment;

// Create a paymentsRequest
var amount = new Amount("USD", 1000);
var paymentRequest = new PaymentRequest
{
    Reference = "Your order number",
    Amount = amount,
    ReturnUrl = @"https://your-company.com/...",
    MerchantAccount = "Your merchantAccount",
};

//Create the http client
var config = new Config
{
    XApiKey = "Your merchant XAPI key",
    Environment = Environment.Test
};
var client = new Client(config);
var checkout = new Checkout(client);
//Make the call to the service. This example code makes a call to /payments
var paymentResponse = checkout.Payments(paymentRequest);

//Example for EU based Endpoint Syncronous
using Adyen;
using Adyen.Constants;

var config = new Config
  {
    XApiKey = "Your merchant XAPI key",
    CloudApiEndPoint = ClientConfig.CloudApiEndPointEULive
  };
var client = new Client(config);

var serializer = new SaleToPoiMessageSerializer();
var saleToPoiRequest = serializer.DeserializeNotification(your_terminal_notification);

using System;
using Adyen.Model.Nexo;
using Adyen.Model.Nexo.Message;
using Adyen.Service;
using Environment = Adyen.Model.Enum.Environment;
 
namespace Adyen.Terminal
{
   public static class Program
   {
        private static string XApiKey = "YOUR-API-KEY";
        private static void Main(string[] args)
        {
            var client = new Client(XApiKey, Environment.Test);
            PosPaymentCloudApi posPaymentCloudApi = new PosPaymentCloudApi(client);
            SaleToPOIResponse response = posPaymentCloudApi.TerminalApiCloudSync(PaymentRequest());
            PaymentResponse paymentResponse = (PaymentResponse) response.MessagePayload;
            Console.WriteLine(paymentResponse.Response.Result);
        }
 
        private static SaleToPOIRequest PaymentRequest()
        {
            var serviceID = "SERVICE_ID"; // ServiceId should be unique for every request
            var saleID = "SALE_ID";
            var POIID = "SERIAL_NUMBER";
            var transactionID = "123459";
            var saleToPOIRequest = new SaleToPOIRequest()
            {
                MessageHeader = new MessageHeader()
                {
                    MessageClass = MessageClassType.Service,
                    MessageCategory = MessageCategoryType.Payment,
                    MessageType = MessageType.Request,
                    ServiceID = serviceID,
                    SaleID = saleID,
                    POIID = POIID
                },
                MessagePayload = new PaymentRequest()
                {
                    SaleData = new SaleData()
                    {
                        SaleTransactionID = new TransactionIdentification()
                        {
                            TransactionID = transactionID,
                            TimeStamp = DateTime.Now
                        }
                    },
                    PaymentTransaction = new PaymentTransaction()
                    {
                        AmountsReq = new AmountsReq()
                        {
                            Currency = "EUR",
                            RequestedAmount = new decimal(10.9)
                        },
                    },
                }
            };
            return saleToPOIRequest;
        }
    }
}

var serializer = new SaleToPoiMessageSerializer();
var saleToPoiRequest = serializer.DeserializeNotification(your_terminal_notification);