Fix fallback logic for default payment method (#2986)

BTCPayServer.Tests/UnitTest1.cs

@@ -2297,19 +2297,27 @@ namespace BTCPayServer.Tests
         }
 
         [Fact]
-        [Trait("Integration", "Integration")]
+        [Trait("Lightning", "Lightning")]
         public async Task CanSetPaymentMethodLimits()
         {
             using (var tester = ServerTester.Create())
             {
+                tester.ActivateLightning();
                 await tester.StartAsync();
                 var user = tester.NewAccount();
-                user.GrantAccess();
+                user.GrantAccess(true);
                 user.RegisterDerivationScheme("BTC");
+                await user.RegisterLightningNodeAsync("BTC");
+
+
+                var lnMethod = new PaymentMethodId("BTC", PaymentTypes.LightningLike).ToString();
+                var btcMethod = new PaymentMethodId("BTC", PaymentTypes.BTCLike).ToString();
+
+                // We allow BTC and LN, but not BTC under 5 USD, so only LN should be in the invoice
                 var vm = Assert.IsType<CheckoutExperienceViewModel>(Assert
                     .IsType<ViewResult>(user.GetController<StoresController>().CheckoutExperience()).Model);
-                Assert.Single(vm.PaymentMethodCriteria);
+                Assert.Equal(2, vm.PaymentMethodCriteria.Count);
-                var criteria = vm.PaymentMethodCriteria.First();
+                var criteria = Assert.Single(vm.PaymentMethodCriteria.Where(m => m.PaymentMethod == btcMethod.ToString()));
                 Assert.Equal(new PaymentMethodId("BTC", BitcoinPaymentType.Instance).ToString(), criteria.PaymentMethod);
                 criteria.Value = "5 USD";
                 criteria.Type = PaymentMethodCriteriaViewModel.CriteriaType.GreaterThan;
@@ -2319,7 +2327,7 @@ namespace BTCPayServer.Tests
                 var invoice = user.BitPay.CreateInvoice(
                     new Invoice()
                     {
-                        Price = 5.5m,
+                        Price = 4.5m,
                         Currency = "USD",
                         PosData = "posData",
                         OrderId = "orderId",
@@ -2328,7 +2336,41 @@ namespace BTCPayServer.Tests
                     }, Facade.Merchant);
 
                 Assert.Single(invoice.CryptoInfo);
-                Assert.Equal(PaymentTypes.BTCLike.ToString(), invoice.CryptoInfo[0].PaymentType);
+                Assert.Equal(PaymentTypes.LightningLike.ToString(), invoice.CryptoInfo[0].PaymentType);
+
+                // Let's replicate https://github.com/btcpayserver/btcpayserver/issues/2963
+                // We allow BTC for more than 5 USD, and LN for less than 150. The default is LN, so the default
+                // payment method should be LN.
+                vm = Assert.IsType<CheckoutExperienceViewModel>(Assert
+                    .IsType<ViewResult>(user.GetController<StoresController>().CheckoutExperience()).Model);
+                vm.DefaultPaymentMethod = lnMethod;
+                criteria = vm.PaymentMethodCriteria.First();
+                criteria.Value = "150 USD";
+                criteria.Type = PaymentMethodCriteriaViewModel.CriteriaType.LessThan;
+                criteria = vm.PaymentMethodCriteria.Skip(1).First();
+                criteria.Value = "5 USD";
+                criteria.Type = PaymentMethodCriteriaViewModel.CriteriaType.GreaterThan;
+                Assert.IsType<RedirectToActionResult>(user.GetController<StoresController>().CheckoutExperience(vm)
+                    .Result);
+                invoice = user.BitPay.CreateInvoice(
+                   new Invoice()
+                   {
+                       Price = 50m,
+                       Currency = "USD",
+                       PosData = "posData",
+                       OrderId = "orderId",
+                       ItemDesc = "Some description",
+                       FullNotifications = true
+                   }, Facade.Merchant);
+                var checkout = (await user.GetController<InvoiceController>().Checkout(invoice.Id)).AssertViewModel<PaymentModel>();
+                Assert.Equal(lnMethod, checkout.PaymentMethodId);
+
+                // If we change store's default, it should change the checkout's default
+                vm.DefaultPaymentMethod = btcMethod;
+                Assert.IsType<RedirectToActionResult>(user.GetController<StoresController>().CheckoutExperience(vm)
+                    .Result);
+                checkout = (await user.GetController<InvoiceController>().Checkout(invoice.Id)).AssertViewModel<PaymentModel>();
+                Assert.Equal(btcMethod, checkout.PaymentMethodId);
             }
         }
 

BTCPayServer/Controllers/GreenField/StoresController.cs

@@ -119,7 +119,7 @@ namespace BTCPayServer.Controllers.GreenField
                 Name = data.StoreName,
                 Website = data.StoreWebsite,
                 SpeedPolicy = data.SpeedPolicy,
-                DefaultPaymentMethod = data.GetDefaultPaymentId(_btcPayNetworkProvider)?.ToStringNormalized(),
+                DefaultPaymentMethod = data.GetDefaultPaymentId()?.ToStringNormalized(),
                 //blob
                 //we do not include DefaultCurrencyPairs,Spread, PreferredExchange, RateScripting, RateScript  in this model and instead opt to set it in stores/storeid/rates endpoints
                 //we do not include ExcludedPaymentMethods in this model and instead opt to set it in stores/storeid/payment-methods endpoints

BTCPayServer/Controllers/InvoiceController.Testing.cs

@@ -59,7 +59,7 @@ namespace BTCPayServer.Controllers
             //var network = invoice.Networks.GetNetwork(invoice.Currency);
             var cryptoCode = "BTC";
             var network = _NetworkProvider.GetNetwork<BTCPayNetwork>(cryptoCode);
-            var paymentMethodId = store.GetDefaultPaymentId(_NetworkProvider);
+            var paymentMethodId = store.GetDefaultPaymentId();
 
             //var network = NetworkProvider.GetNetwork<BTCPayNetwork>("BTC");
             var bitcoinAddressString = invoice.GetPaymentMethod(paymentMethodId).GetPaymentMethodDetails().GetPaymentDestination();

BTCPayServer/Controllers/InvoiceController.UI.cs

@@ -460,18 +460,6 @@ namespace BTCPayServer.Controllers
             return View(model);
         }
 
-        private PaymentMethodId GetDefaultInvoicePaymentId(
-            PaymentMethodId[] paymentMethodIds,
-            InvoiceEntity invoice
-        )
-        {
-            PaymentMethodId.TryParse(invoice.DefaultPaymentMethod, out var defaultPaymentId);
-
-            return paymentMethodIds.FirstOrDefault(f => f == defaultPaymentId) ??
-                paymentMethodIds.FirstOrDefault(f => f.CryptoCode == defaultPaymentId?.CryptoCode) ??
-                paymentMethodIds.FirstOrDefault();
-        }
-
         private async Task<PaymentModel?> GetInvoiceModel(string invoiceId, PaymentMethodId? paymentMethodId, string? lang)
         {
             var invoice = await _InvoiceRepository.GetInvoice(invoiceId);
@@ -481,19 +469,35 @@ namespace BTCPayServer.Controllers
             bool isDefaultPaymentId = false;
             if (paymentMethodId is null)
             {
-                paymentMethodId = GetDefaultInvoicePaymentId(store.GetEnabledPaymentIds(_NetworkProvider), invoice) ?? store.GetDefaultPaymentId(_NetworkProvider);
+                var enabledPaymentIds = store.GetEnabledPaymentIds(_NetworkProvider) ?? Array.Empty<PaymentMethodId>();
+                PaymentMethodId? invoicePaymentId = invoice.GetDefaultPaymentMethod();
+                PaymentMethodId? storePaymentId = store.GetDefaultPaymentId();
+                if (invoicePaymentId is PaymentMethodId)
+                {
+                    if (enabledPaymentIds.Contains(invoicePaymentId))
+                        paymentMethodId = invoicePaymentId;
+                }
+                if (paymentMethodId is null && storePaymentId is PaymentMethodId)
+                {
+                    if (enabledPaymentIds.Contains(storePaymentId))
+                        paymentMethodId = storePaymentId;
+                }
+                if (paymentMethodId is null && invoicePaymentId is PaymentMethodId)
+                {
+                    paymentMethodId = invoicePaymentId.FindNearest(enabledPaymentIds);
+                }
+                if (paymentMethodId is null && storePaymentId is PaymentMethodId)
+                {
+                    paymentMethodId = storePaymentId.FindNearest(enabledPaymentIds);
+                }
+                if (paymentMethodId is null)
+                {
+                    paymentMethodId = enabledPaymentIds.First();
+                }
                 isDefaultPaymentId = true;
             }
             BTCPayNetworkBase network = _NetworkProvider.GetNetwork<BTCPayNetworkBase>(paymentMethodId.CryptoCode);
-            if (network == null && isDefaultPaymentId)
+            if (network is null || !invoice.Support(paymentMethodId))
-            {
-                //TODO: need to look into a better way for this as it does not scale
-                network = _NetworkProvider.GetAll().OfType<BTCPayNetwork>().FirstOrDefault();
-                paymentMethodId = new PaymentMethodId(network.CryptoCode, PaymentTypes.BTCLike);
-            }
-            if (invoice == null || network == null)
-                return null;
-            if (!invoice.Support(paymentMethodId))
             {
                 if (!isDefaultPaymentId)
                     return null;

BTCPayServer/Controllers/StoresController.cs

@@ -412,7 +412,10 @@ namespace BTCPayServer.Controllers
 
         void SetCryptoCurrencies(CheckoutExperienceViewModel vm, Data.StoreData storeData)
         {
-            var choices = storeData.GetEnabledPaymentIds(_NetworkProvider)
+            var enabled = storeData.GetEnabledPaymentIds(_NetworkProvider);
+            var defaultPaymentId = storeData.GetDefaultPaymentId();
+            var defaultChoice = defaultPaymentId is PaymentMethodId ? defaultPaymentId.FindNearest(enabled) : null;
+            var choices = enabled
                 .Select(o =>
                     new CheckoutExperienceViewModel.Format()
                     {
@@ -420,9 +423,7 @@ namespace BTCPayServer.Controllers
                         Value = o.ToString(),
                         PaymentId = o
                     }).ToArray();
-
+            var chosen = defaultChoice is null ? null : choices.FirstOrDefault(c => defaultChoice.ToString().Equals(c.Value, StringComparison.OrdinalIgnoreCase));
-            var defaultPaymentId = storeData.GetDefaultPaymentId(_NetworkProvider);
-            var chosen = choices.FirstOrDefault(c => c.PaymentId == defaultPaymentId);
             vm.PaymentMethods = new SelectList(choices, nameof(chosen.Value), nameof(chosen.Name), chosen?.Value);
             vm.DefaultPaymentMethod = chosen?.Value;
         }
@@ -434,7 +435,7 @@ namespace BTCPayServer.Controllers
             bool needUpdate = false;
             var blob = CurrentStore.GetStoreBlob();
             var defaultPaymentMethodId = model.DefaultPaymentMethod == null ? null : PaymentMethodId.Parse(model.DefaultPaymentMethod);
-            if (CurrentStore.GetDefaultPaymentId(_NetworkProvider) != defaultPaymentMethodId)
+            if (CurrentStore.GetDefaultPaymentId() != defaultPaymentMethodId)
             {
                 needUpdate = true;
                 CurrentStore.SetDefaultPaymentId(defaultPaymentMethodId);

BTCPayServer/Data/StoreDataExtensions.cs

@@ -1,3 +1,4 @@
+#nullable enable
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -12,14 +13,10 @@ namespace BTCPayServer.Data
     public static class StoreDataExtensions
     {
 #pragma warning disable CS0618
-        public static PaymentMethodId GetDefaultPaymentId(this StoreData storeData, BTCPayNetworkProvider networks)
+        public static PaymentMethodId? GetDefaultPaymentId(this StoreData storeData)
         {
-            PaymentMethodId[] paymentMethodIds = storeData.GetEnabledPaymentIds(networks);
             PaymentMethodId.TryParse(storeData.DefaultCrypto, out var defaultPaymentId);
-            var chosen = paymentMethodIds.FirstOrDefault(f => f == defaultPaymentId) ??
+            return defaultPaymentId;
-                         paymentMethodIds.FirstOrDefault(f => f.CryptoCode == defaultPaymentId?.CryptoCode) ??
-                         paymentMethodIds.FirstOrDefault();
-            return chosen;
         }
 
         public static PaymentMethodId[] GetEnabledPaymentIds(this StoreData storeData, BTCPayNetworkProvider networks)
@@ -104,7 +101,7 @@ namespace BTCPayServer.Data
         /// </summary>
         /// <param name="paymentMethodId">The paymentMethodId</param>
         /// <param name="supportedPaymentMethod">The payment method, or null to remove</param>
-        public static void SetSupportedPaymentMethod(this StoreData storeData, PaymentMethodId paymentMethodId, ISupportedPaymentMethod supportedPaymentMethod)
+        public static void SetSupportedPaymentMethod(this StoreData storeData, PaymentMethodId? paymentMethodId, ISupportedPaymentMethod? supportedPaymentMethod)
         {
             if (supportedPaymentMethod != null && paymentMethodId != null && paymentMethodId != supportedPaymentMethod.PaymentId)
             {

BTCPayServer/Payments/PaymentMethodId.cs

@@ -1,4 +1,7 @@
+#nullable enable
 using System;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
 
 namespace BTCPayServer.Payments
 {
@@ -8,6 +11,13 @@ namespace BTCPayServer.Payments
     /// </summary>
     public class PaymentMethodId
     {
+        public PaymentMethodId? FindNearest(PaymentMethodId[] others)
+        {
+            if (others is null)
+                throw new ArgumentNullException(nameof(others));
+            return others.FirstOrDefault(f => f == this) ??
+                   others.FirstOrDefault(f => f.CryptoCode == CryptoCode);
+        }
         public PaymentMethodId(string cryptoCode, PaymentType paymentType)
         {
             if (cryptoCode == null)
@@ -31,23 +41,22 @@ namespace BTCPayServer.Payments
         public PaymentType PaymentType { get; private set; }
 
 
-        public override bool Equals(object obj)
+        public override bool Equals(object? obj)
         {
-            PaymentMethodId item = obj as PaymentMethodId;
+            if (obj is PaymentMethodId id)
-            if (item == null)
+                return ToString().Equals(id.ToString(), StringComparison.OrdinalIgnoreCase);
             return false;
-            return ToString().Equals(item.ToString(), StringComparison.InvariantCulture);
         }
-        public static bool operator ==(PaymentMethodId a, PaymentMethodId b)
+        public static bool operator ==(PaymentMethodId? a, PaymentMethodId? b)
         {
-            if (System.Object.ReferenceEquals(a, b))
+            if (a is null && b is null)
                 return true;
-            if (((object)a == null) || ((object)b == null))
+            if (a is PaymentMethodId ai && b is PaymentMethodId bi)
+                return ai.Equals(bi);
             return false;
-            return a.ToString() == b.ToString();
         }
 
-        public static bool operator !=(PaymentMethodId a, PaymentMethodId b)
+        public static bool operator !=(PaymentMethodId? a, PaymentMethodId? b)
         {
             return !(a == b);
         }
@@ -84,12 +93,12 @@ namespace BTCPayServer.Payments
             return $"{CryptoCode} ({PaymentType.ToPrettyString()})";
         }
         static char[] Separators = new[] { '_', '-' };
-        public static PaymentMethodId TryParse(string str)
+        public static PaymentMethodId? TryParse(string? str)
         {
             TryParse(str, out var r);
             return r;
         }
-        public static bool TryParse(string str, out PaymentMethodId paymentMethodId)
+        public static bool TryParse(string? str, [MaybeNullWhen(false)] out PaymentMethodId paymentMethodId)
         {
             str ??= "";
             paymentMethodId = null;

BTCPayServer/Services/Invoices/InvoiceEntity.cs

@@ -258,7 +258,13 @@ namespace BTCPayServer.Services.Invoices
         public decimal Price { get; set; }
         public string Currency { get; set; }
         public string DefaultPaymentMethod { get; set; }
-
+#nullable enable
+        public PaymentMethodId? GetDefaultPaymentMethod()
+        {
+            PaymentMethodId.TryParse(DefaultPaymentMethod, out var id);
+            return id;
+        }
+#nullable restore
         [JsonExtensionData]
         public IDictionary<string, JToken> AdditionalData { get; set; }