btcpayserver/BTCPayServer/Controllers/InvoiceController.PaymentProtocol.cs

using BTCPayServer.Filters;
using Microsoft.Extensions.Logging;
using BTCPayServer.Logging;
using Microsoft.AspNetCore.Mvc;
using NBitcoin;
using NBitcoin.Payment;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace BTCPayServer.Controllers
{
    public partial class InvoiceController
    {
		[HttpGet]
		[Route("i/{invoiceId}")]
		[AcceptMediaTypeConstraint("application/bitcoin-paymentrequest")]
		public async Task<IActionResult> GetInvoiceRequest(string invoiceId)
		{
			var invoice = await _InvoiceRepository.GetInvoice(null, invoiceId);
			if(invoice == null || invoice.IsExpired())
				return NotFound();

			var dto = invoice.EntityToDTO();
			PaymentRequest request = new PaymentRequest
			{
				DetailsVersion = 1
			};
			request.Details.Expires = invoice.ExpirationTime;
			request.Details.Memo = invoice.ProductInformation.ItemDesc;
			request.Details.Network = _Network;
			request.Details.Outputs.Add(new PaymentOutput() { Amount = dto.BTCDue, Script = BitcoinAddress.Create(dto.BitcoinAddress, _Network).ScriptPubKey });
			request.Details.MerchantData = Encoding.UTF8.GetBytes(invoice.Id);
			request.Details.Time = DateTimeOffset.UtcNow;
			request.Details.PaymentUrl = new Uri(invoice.ServerUrl.WithTrailingSlash() + ($"i/{invoice.Id}"), UriKind.Absolute);

			var store = await _StoreRepository.FindStore(invoice.StoreId);
			if(store == null)
				throw new BitpayHttpException(401, "Unknown store");

			if(store.StoreCertificate != null)
			{
				try
				{
					request.Sign(store.StoreCertificate, PKIType.X509SHA256);
				}
				catch(Exception ex)
				{
					Logs.PayServer.LogWarning(ex, "Error while signing payment request");
				}
			}

			return new PaymentRequestActionResult(request);
		}

		[HttpPost]
		[Route("i/{invoiceId}", Order = 99)]
		[MediaTypeConstraint("application/bitcoin-payment")]
		public async Task<IActionResult> PostPayment(string invoiceId)
		{
			var invoice = await _InvoiceRepository.GetInvoice(null, invoiceId);
			if(invoice == null || invoice.IsExpired())
				return NotFound();
			var payment = PaymentMessage.Load(Request.Body);
			var unused = _Wallet.BroadcastTransactionsAsync(payment.Transactions);
			await _InvoiceRepository.AddRefundsAsync(invoiceId, payment.RefundTo.Select(p => new TxOut(p.Amount, p.Script)).ToArray());
			return new PaymentAckActionResult(payment.CreateACK(invoiceId + " is currently processing, thanks for your purchase..."));
		}
	}
}