Fix crash when creating a token

Payment Tolerance

BTCPayServer.Tests/RateRulesTest.cs

@@ -113,12 +113,21 @@ namespace BTCPayServer.Tests
             builder.AppendLine("DOGE_BTC = 2000");
             Assert.True(RateRules.TryParse(builder.ToString(), out rules));
             rules.GlobalMultiplier = 1.1m;
+
             rule2 = rules.GetRuleFor(CurrencyPair.Parse("DOGE_USD"));
             Assert.Equal("(2000 * (-3 + coinbase(BTC_CAD) + 50 - 5)) * 1.1", rule2.ToString());
             rule2.ExchangeRates.SetRate("coinbase", CurrencyPair.Parse("BTC_CAD"), 1000m);
             Assert.True(rule2.Reevaluate());
             Assert.Equal("(2000 * (-3 + 1000 + 50 - 5)) * 1.1", rule2.ToString(true));
             Assert.Equal((2000m * (-3m + 1000m + 50m - 5m)) * 1.1m, rule2.Value.Value);
+
+            // Test inverse
+            rule2 = rules.GetRuleFor(CurrencyPair.Parse("USD_DOGE"));
+            Assert.Equal("(1 / (2000 * (-3 + coinbase(BTC_CAD) + 50 - 5))) * 1.1", rule2.ToString());
+            rule2.ExchangeRates.SetRate("coinbase", CurrencyPair.Parse("BTC_CAD"), 1000m);
+            Assert.True(rule2.Reevaluate());
+            Assert.Equal("(1 / (2000 * (-3 + 1000 + 50 - 5))) * 1.1", rule2.ToString(true));
+            Assert.Equal(( 1.0m / (2000m * (-3m + 1000m + 50m - 5m))) * 1.1m, rule2.Value.Value);
             ////////
         }
     }

BTCPayServer.Tests/UnitTest1.cs

@@ -229,6 +229,73 @@ namespace BTCPayServer.Tests
 #pragma warning restore CS0618
         }
 
+        [Fact]
+        public void CanAcceptInvoiceWithTolerance()
+        {
+            var entity = new InvoiceEntity();
+#pragma warning disable CS0618
+            entity.Payments = new List<PaymentEntity>();
+            entity.SetPaymentMethod(new PaymentMethod() { CryptoCode = "BTC", Rate = 5000, TxFee = Money.Coins(0.1m) });
+            entity.ProductInformation = new ProductInformation() { Price = 5000 };
+            entity.PaymentTolerance = 0;
+
+
+            var paymentMethod = entity.GetPaymentMethods(null).TryGet("BTC", PaymentTypes.BTCLike);
+            var accounting = paymentMethod.Calculate();
+            Assert.Equal(Money.Coins(1.1m), accounting.Due);
+            Assert.Equal(Money.Coins(1.1m), accounting.TotalDue);
+            Assert.Equal(Money.Coins(1.1m), accounting.MinimumTotalDue);
+
+            entity.PaymentTolerance = 10;
+            accounting = paymentMethod.Calculate();
+            Assert.Equal(Money.Coins(0.99m), accounting.MinimumTotalDue);
+
+            entity.PaymentTolerance = 100;
+            accounting = paymentMethod.Calculate();
+            Assert.Equal(Money.Coins(0), accounting.MinimumTotalDue);
+
+        }
+
+        [Fact]
+        public void CanAcceptInvoiceWithTolerance2()
+        {
+            using (var tester = ServerTester.Create())
+            {
+                tester.Start();
+                var user = tester.NewAccount();
+                user.GrantAccess();
+                user.RegisterDerivationScheme("BTC");
+                
+                // Set tolerance to 50%
+                var stores = user.GetController<StoresController>();
+                var vm = Assert.IsType<StoreViewModel>(Assert.IsType<ViewResult>(stores.UpdateStore()).Model);
+                Assert.Equal(0.0, vm.PaymentTolerance);
+                vm.PaymentTolerance = 50.0;
+                Assert.IsType<RedirectToActionResult>(stores.UpdateStore(vm).Result);
+
+                var invoice = user.BitPay.CreateInvoice(new Invoice()
+                {
+                    Buyer = new Buyer() { email = "test@fwf.com" },
+                    Price = 5000.0,
+                    Currency = "USD",
+                    PosData = "posData",
+                    OrderId = "orderId",
+                    ItemDesc = "Some description",
+                    FullNotifications = true
+                }, Facade.Merchant);
+
+                // Pays 75%
+                var invoiceAddress = BitcoinAddress.Create(invoice.CryptoInfo[0].Address, tester.ExplorerNode.Network);
+                tester.ExplorerNode.SendToAddress(invoiceAddress, Money.Satoshis((decimal)invoice.BtcDue.Satoshi * 0.75m));
+
+                Eventually(() =>
+                {
+                    var localInvoice = user.BitPay.GetInvoice(invoice.Id, Facade.Merchant);
+                    Assert.Equal("paid", localInvoice.Status);
+                });
+            }
+        }
+
         [Fact]
         public void CanPayUsingBIP70()
         {
@@ -531,6 +598,53 @@ namespace BTCPayServer.Tests
             }
         }
 
+        [Fact]
+        public void CanListInvoices()
+        {
+            using (var tester = ServerTester.Create())
+            {
+                tester.Start();
+                var acc = tester.NewAccount();
+                acc.GrantAccess();
+                acc.RegisterDerivationScheme("BTC");
+                // First we try payment with a merchant having only BTC
+                var invoice = acc.BitPay.CreateInvoice(new Invoice()
+                {
+                    Price = 500,
+                    Currency = "USD",
+                    PosData = "posData",
+                    OrderId = "orderId",
+                    ItemDesc = "Some description",
+                    FullNotifications = true
+                }, Facade.Merchant);
+                
+                var cashCow = tester.ExplorerNode;
+                var invoiceAddress = BitcoinAddress.Create(invoice.CryptoInfo[0].Address, cashCow.Network);
+                var firstPayment = invoice.CryptoInfo[0].TotalDue - Money.Satoshis(10);
+                cashCow.SendToAddress(invoiceAddress, firstPayment);
+                Eventually(() =>
+                {
+                    invoice = acc.BitPay.GetInvoice(invoice.Id);
+                    Assert.Equal(firstPayment, invoice.CryptoInfo[0].Paid);
+                });
+
+
+                AssertSearchInvoice(acc, true, invoice.Id, $"storeid:{acc.StoreId}");
+                AssertSearchInvoice(acc, false, invoice.Id, $"storeid:blah");
+                AssertSearchInvoice(acc, true, invoice.Id, $"{invoice.Id}");
+                AssertSearchInvoice(acc, true, invoice.Id, $"exceptionstatus:paidPartial");
+                AssertSearchInvoice(acc, false, invoice.Id, $"exceptionstatus:paidOver");
+                AssertSearchInvoice(acc, true, invoice.Id, $"unusual:true");
+                AssertSearchInvoice(acc, false, invoice.Id, $"unusual:false");
+            }
+        }
+
+        private void AssertSearchInvoice(TestAccount acc, bool expected, string invoiceId, string filter)
+        {
+            var result = (Models.InvoicingModels.InvoicesModel)((ViewResult)acc.GetController<InvoiceController>().ListInvoices(filter).Result).Model;
+            Assert.Equal(expected, result.Invoices.Any(i => i.InvoiceId == invoiceId));
+        }
+
         [Fact]
         public void CanRBFPayment()
         {

BTCPayServer.Tests/docker-compose.yml

@@ -46,7 +46,7 @@ services:
       - lightning-charged
 
   nbxplorer:
-    image: nicolasdorier/nbxplorer:1.0.2.2
+    image: nicolasdorier/nbxplorer:1.0.2.3
     ports:
       - "32838:32838"
     expose: 
@@ -89,7 +89,7 @@ services:
       - "bitcoin_datadir:/data"
 
   customer_lightningd:
-    image: nicolasdorier/clightning:0.0.0.11-dev
+    image: nicolasdorier/clightning:0.0.0.12-dev
     environment: 
       EXPOSE_TCP: "true"
       LIGHTNINGD_OPT: |

BTCPayServer/BTCPayNetworkProvider.Dogecoin.cs

@@ -20,7 +20,11 @@ namespace BTCPayServer
                 NBitcoinNetwork = nbxplorerNetwork.NBitcoinNetwork,
                 NBXplorerNetwork = nbxplorerNetwork,
                 UriScheme = "dogecoin",
-                DefaultRateRules = new[] { "DOGE_X = bittrex(DOGE_BTC) * BTC_X" },
+                DefaultRateRules = new[] 
+                {
+                                "DOGE_X = DOGE_BTC * BTC_X",
+                                "DOGE_BTC = bittrex(DOGE_BTC)"
+                },
                 CryptoImagePath = "imlegacy/dogecoin.png",
                 DefaultSettings = BTCPayDefaultSettings.GetDefaultSettings(NetworkType),
                 CoinType = NetworkType == NetworkType.Mainnet ? new KeyPath("3'") : new KeyPath("1'")

BTCPayServer/BTCPayServer.csproj

@@ -2,7 +2,7 @@
   <PropertyGroup>
     <OutputType>Exe</OutputType>
     <TargetFramework>netcoreapp2.0</TargetFramework>
-		<Version>1.0.2.1</Version>
+		<Version>1.0.2.8</Version>
     <NoWarn>NU1701,CA1816,CA1308,CA1810,CA2208</NoWarn>
   </PropertyGroup>
   <ItemGroup>
@@ -43,7 +43,7 @@
     <PackageReference Include="NBitcoin" Version="4.1.1.4" />
     <PackageReference Include="NBitpayClient" Version="1.0.0.18" />	  
     <PackageReference Include="DBreeze" Version="1.87.0" />
-    <PackageReference Include="NBXplorer.Client" Version="1.0.2.3" />
+    <PackageReference Include="NBXplorer.Client" Version="1.0.2.4" />
     <PackageReference Include="NicolasDorier.CommandLine" Version="1.0.0.1" />
     <PackageReference Include="NicolasDorier.CommandLine.Configuration" Version="1.0.0.2" />
     <PackageReference Include="NicolasDorier.StandardConfiguration" Version="1.0.0.13" />

BTCPayServer/Controllers/InvoiceController.UI.cs

@@ -370,14 +370,19 @@ namespace BTCPayServer.Controllers
                 Count = count,
                 Skip = skip,
                 UserId = GetUserId(),
+                Unusual = !filterString.Filters.ContainsKey("unusual") ? null
+                          : !bool.TryParse(filterString.Filters["unusual"].First(), out var r) ? (bool?)null
+                          : r,
                 Status = filterString.Filters.ContainsKey("status") ? filterString.Filters["status"].ToArray() : null,
+                ExceptionStatus = filterString.Filters.ContainsKey("exceptionstatus") ? filterString.Filters["exceptionstatus"].ToArray() : null,
                 StoreId = filterString.Filters.ContainsKey("storeid") ? filterString.Filters["storeid"].ToArray() : null
             }))
             {
                 model.SearchTerm = searchTerm;
                 model.Invoices.Add(new InvoiceModel()
                 {
-                    Status = invoice.Status,
+                    Status = invoice.Status + (invoice.ExceptionStatus == null ? string.Empty : $" ({invoice.ExceptionStatus})"),
+                    ShowCheckout = invoice.Status == "new",
                     Date = (DateTimeOffset.UtcNow - invoice.InvoiceTime).Prettify() + " ago",
                     InvoiceId = invoice.Id,
                     OrderId = invoice.OrderId ?? string.Empty,

BTCPayServer/Controllers/InvoiceController.cs

@@ -98,6 +98,7 @@ namespace BTCPayServer.Controllers
             entity.ExtendedNotifications = invoice.ExtendedNotifications;
             entity.NotificationURL = notificationUri?.AbsoluteUri;
             entity.BuyerInformation = Map<Invoice, BuyerInformation>(invoice);
+            entity.PaymentTolerance = storeBlob.PaymentTolerance;
             //Another way of passing buyer info to support
             FillBuyerInfo(invoice.Buyer, entity.BuyerInformation);
             if (entity?.BuyerInformation?.BuyerEmail != null)

BTCPayServer/Controllers/ServerController.cs

@@ -243,10 +243,7 @@ namespace BTCPayServer.Controllers
             {
                 try
                 {
-                    if(string.IsNullOrWhiteSpace(model.Settings.From)
-                       || string.IsNullOrWhiteSpace(model.TestEmail)
-                       || string.IsNullOrWhiteSpace(model.Settings.Login)
-                       || string.IsNullOrWhiteSpace(model.Settings.Server))
+                    if(!model.Settings.IsComplete())
                     {
                         model.StatusMessage = "Error: Required fields missing";
                         return View(model);

BTCPayServer/Controllers/StoresController.cs

@@ -431,6 +431,7 @@ namespace BTCPayServer.Controllers
             vm.MonitoringExpiration = storeBlob.MonitoringExpiration;
             vm.InvoiceExpiration = storeBlob.InvoiceExpiration;
             vm.LightningDescriptionTemplate = storeBlob.LightningDescriptionTemplate;
+            vm.PaymentTolerance = storeBlob.PaymentTolerance;
             return View(vm);
         }
 
@@ -496,6 +497,7 @@ namespace BTCPayServer.Controllers
             blob.MonitoringExpiration = model.MonitoringExpiration;
             blob.InvoiceExpiration = model.InvoiceExpiration;
             blob.LightningDescriptionTemplate = model.LightningDescriptionTemplate ?? string.Empty;
+            blob.PaymentTolerance = model.PaymentTolerance;
 
             if (StoreData.SetStoreBlob(blob))
             {
@@ -644,11 +646,11 @@ namespace BTCPayServer.Controllers
             {
                 var stores = await _Repo.GetStoresByUserId(userId);
                 model.Stores = new SelectList(stores.Where(s => s.HasClaim(Policies.CanModifyStoreSettings.Key)), nameof(StoreData.Id), nameof(StoreData.StoreName), storeId);
-            }
-            if (model.Stores.Count() == 0)
-            {
-                StatusMessage = "Error: You need to be owner of at least one store before pairing";
-                return RedirectToAction(nameof(UserStoresController.ListStores), "UserStores");
+                if (model.Stores.Count() == 0)
+                {
+                    StatusMessage = "Error: You need to be owner of at least one store before pairing";
+                    return RedirectToAction(nameof(UserStoresController.ListStores), "UserStores");
+                }
             }
             return View(model);
         }

BTCPayServer/Data/StoreData.cs

@@ -247,6 +247,7 @@ namespace BTCPayServer.Data
         {
             InvoiceExpiration = 15;
             MonitoringExpiration = 60;
+            PaymentTolerance = 0;
             RequiresRefundEmail = true;
         }
         public bool NetworkFeeDisabled
@@ -326,6 +327,10 @@ namespace BTCPayServer.Data
             }
         }
 
+        [DefaultValue(0)]
+        [JsonProperty(DefaultValueHandling = DefaultValueHandling.Populate)]
+        public double PaymentTolerance { get; set; }
+
         public BTCPayServer.Rating.RateRules GetRateRules(BTCPayNetworkProvider networkProvider)
         {
             if (!RateScripting || 

BTCPayServer/HostedServices/InvoiceNotificationManager.cs

@@ -305,7 +305,10 @@ namespace BTCPayServer.HostedServices
             leases.Add(_EventAggregator.Subscribe<InvoiceEvent>(async e =>
             {
                 var invoice = await _InvoiceRepository.GetInvoice(null, e.InvoiceId);
-                await SaveEvent(invoice.Id, e);
+                List<Task> tasks = new List<Task>();
+
+                // Awaiting this later help make sure invoices should arrive in order
+                tasks.Add(SaveEvent(invoice.Id, e));
 
                 // we need to use the status in the event and not in the invoice. The invoice might now be in another status.
                 if (invoice.FullNotifications)
@@ -315,20 +318,22 @@ namespace BTCPayServer.HostedServices
                        e.Name == "invoice_failedToConfirm" ||
                        e.Name == "invoice_markedInvalid" ||
                        e.Name == "invoice_failedToConfirm" ||
-                       e.Name == "invoice_completed"
+                       e.Name == "invoice_completed" ||
+                       e.Name == "invoice_expiredPaidPartial"
                      )
-                        await Notify(invoice);
+                        tasks.Add(Notify(invoice));
                 }
 
                 if (e.Name == "invoice_confirmed")
                 {
-                    await Notify(invoice);
+                    tasks.Add(Notify(invoice));
                 }
 
                 if (invoice.ExtendedNotifications)
                 {
-                    await Notify(invoice, e.EventCode, e.Name);
+                    tasks.Add(Notify(invoice, e.EventCode, e.Name));
                 }
+                await Task.WhenAll(tasks.ToArray());
             }));
 
 

BTCPayServer/HostedServices/InvoiceWatcher.cs

@@ -68,6 +68,8 @@ namespace BTCPayServer.HostedServices
 
                 context.Events.Add(new InvoiceEvent(invoice, 1004, "invoice_expired"));
                 invoice.Status = "expired";
+                if(invoice.ExceptionStatus == "paidPartial")
+                    context.Events.Add(new InvoiceEvent(invoice, 2000, "invoice_expiredPaidPartial"));
             }
 
             var payments = invoice.GetPayments().Where(p => p.Accounted).ToArray();
@@ -78,7 +80,7 @@ namespace BTCPayServer.HostedServices
             var network = _NetworkProvider.GetNetwork(paymentMethod.GetId().CryptoCode);
             if (invoice.Status == "new" || invoice.Status == "expired")
             {
-                if (accounting.Paid >= accounting.TotalDue)
+                if (accounting.Paid >= accounting.MinimumTotalDue)
                 {
                     if (invoice.Status == "new")
                     {
@@ -96,17 +98,17 @@ namespace BTCPayServer.HostedServices
                     }
                 }
 
-                if (accounting.Paid < accounting.TotalDue && invoice.GetPayments().Count != 0 && invoice.ExceptionStatus != "paidPartial")
+                if (accounting.Paid < accounting.MinimumTotalDue && invoice.GetPayments().Count != 0 && invoice.ExceptionStatus != "paidPartial")
                 {
-                    invoice.ExceptionStatus = "paidPartial";
-                    context.MarkDirty();
+                        invoice.ExceptionStatus = "paidPartial";
+                        context.MarkDirty();
                 }
             }
 
             // Just make sure RBF did not cancelled a payment
             if (invoice.Status == "paid")
             {
-                if (accounting.Paid == accounting.TotalDue && invoice.ExceptionStatus == "paidOver")
+                if (accounting.MinimumTotalDue <= accounting.Paid && accounting.Paid <= accounting.TotalDue && invoice.ExceptionStatus == "paidOver")
                 {
                     invoice.ExceptionStatus = null;
                     context.MarkDirty();
@@ -118,7 +120,7 @@ namespace BTCPayServer.HostedServices
                     context.MarkDirty();
                 }
 
-                if (accounting.Paid < accounting.TotalDue)
+                if (accounting.Paid < accounting.MinimumTotalDue)
                 {
                     invoice.Status = "new";
                     invoice.ExceptionStatus = accounting.Paid == Money.Zero ? null : "paidPartial";
@@ -134,14 +136,14 @@ namespace BTCPayServer.HostedServices
                    (invoice.MonitoringExpiration < DateTimeOffset.UtcNow)
                    &&
                    // And not enough amount confirmed
-                   (confirmedAccounting.Paid < accounting.TotalDue))
+                   (confirmedAccounting.Paid < accounting.MinimumTotalDue))
                 {
                     await _InvoiceRepository.UnaffectAddress(invoice.Id);
                     context.Events.Add(new InvoiceEvent(invoice, 1013, "invoice_failedToConfirm"));
                     invoice.Status = "invalid";
                     context.MarkDirty();
                 }
-                else if (confirmedAccounting.Paid >= accounting.TotalDue)
+                else if (confirmedAccounting.Paid >= accounting.MinimumTotalDue)
                 {
                     await _InvoiceRepository.UnaffectAddress(invoice.Id);
                     context.Events.Add(new InvoiceEvent(invoice, 1005, "invoice_confirmed"));
@@ -153,7 +155,7 @@ namespace BTCPayServer.HostedServices
             if (invoice.Status == "confirmed")
             {
                 var completedAccounting = paymentMethod.Calculate(p => p.GetCryptoPaymentData().PaymentCompleted(p, network));
-                if (completedAccounting.Paid >= accounting.TotalDue)
+                if (completedAccounting.Paid >= accounting.MinimumTotalDue)
                 {
                     context.Events.Add(new InvoiceEvent(invoice, 1006, "invoice_completed"));
                     invoice.Status = "complete";
@@ -289,7 +291,7 @@ namespace BTCPayServer.HostedServices
                             if (updateContext.Dirty)
                             {
                                 await _InvoiceRepository.UpdateInvoiceStatus(invoice.Id, invoice.Status, invoice.ExceptionStatus);
-                                updateContext.Events.Add(new InvoiceDataChangedEvent(invoice));
+                                updateContext.Events.Insert(0, new InvoiceDataChangedEvent(invoice));
                             }
 
                             foreach (var evt in updateContext.Events)

BTCPayServer/Models/InvoicingModels/InvoicesModel.cs

@@ -49,6 +49,8 @@ namespace BTCPayServer.Models.InvoicingModels
         {
             get; set;
         }
+        public bool ShowCheckout { get; set; }
+        public string ExceptionStatus { get; set; }
         public string AmountCurrency
         {
             get; set;

BTCPayServer/Models/StoreViewModels/StoreViewModel.cs

@@ -85,5 +85,13 @@ namespace BTCPayServer.Models.StoreViewModels
         {
             get; set;
         } = new List<LightningNode>();
+
+        [Display(Name = "Consider the invoice paid even if the paid amount is ... % less than expected")]
+        [Range(0, 100)]
+        public double PaymentTolerance
+        {
+            get;
+            set;
+        }
     }
 }

BTCPayServer/Rating/CurrencyPair.cs

@@ -45,6 +45,11 @@ namespace BTCPayServer.Rating
                 var currencyPair = splitted[0];
                 if (currencyPair.Length < 6 || currencyPair.Length > 10)
                     return false;
+                if (currencyPair.Length == 6)
+                { 
+                    value = new CurrencyPair(currencyPair.Substring(0,3), currencyPair.Substring(3, 3));
+                    return true;
+                }
                 for (int i = 3; i < 5; i++)
                 {
                     var potentialCryptoName = currencyPair.Substring(0, i);
@@ -90,5 +95,10 @@ namespace BTCPayServer.Rating
         {
             return $"{Left}_{Right}";
         }
+
+        public CurrencyPair Inverse()
+        {
+            return new CurrencyPair(Right, Left);
+        }
     }
 }

BTCPayServer/Rating/RateRules.cs

@@ -133,28 +133,31 @@ namespace BTCPayServer.Rating
             if (currencyPair.Left == "X" || currencyPair.Right == "X")
                 throw new ArgumentException(paramName: nameof(currencyPair), message: "Invalid X currency");
             var candidate = FindBestCandidate(currencyPair);
-
             if (GlobalMultiplier != decimal.One)
             {
                 candidate = CreateExpression($"({candidate}) * {GlobalMultiplier.ToString(CultureInfo.InvariantCulture)}");
             }
             return new RateRule(this, currencyPair, candidate);
         }
-
+        
         public ExpressionSyntax FindBestCandidate(CurrencyPair p)
         {
-            var candidates = new List<(CurrencyPair Pair, int Prioriy, ExpressionSyntax Expression)>();
+            var invP = p.Inverse();
+            var candidates = new List<(CurrencyPair Pair, int Prioriy, ExpressionSyntax Expression, bool Inverse)>();
             foreach (var pair in new[]
             {
-                (Pair: p, Priority: 0),
-                (Pair: new CurrencyPair(p.Left, "X"), Priority: 1),
-                (Pair: new CurrencyPair("X", p.Right), Priority: 1),
-                (Pair: new CurrencyPair("X", "X"), Priority: 2)
+                (Pair: p, Priority: 0, Inverse: false),
+                (Pair: new CurrencyPair(p.Left, "X"), Priority: 1, Inverse: false),
+                (Pair: new CurrencyPair("X", p.Right), Priority: 1, Inverse: false),
+                (Pair: invP, Priority: 2, Inverse: true),
+                (Pair: new CurrencyPair(invP.Left, "X"), Priority: 3, Inverse: true),
+                (Pair: new CurrencyPair("X", invP.Right), Priority: 3, Inverse: true),
+                (Pair: new CurrencyPair("X", "X"), Priority: 4, Inverse: false)
             })
             {
                 if (ruleList.ExpressionsByPair.TryGetValue(pair.Pair, out var expression))
                 {
-                    candidates.Add((pair.Pair, pair.Priority, expression.Expression));
+                    candidates.Add((pair.Pair, pair.Priority, expression.Expression, pair.Inverse));
                 }
             }
             if (candidates.Count == 0)
@@ -163,8 +166,9 @@ namespace BTCPayServer.Rating
                     .OrderBy(c => c.Prioriy)
                     .ThenBy(c => c.Expression.Span.Start)
                     .First();
-
-            return best.Expression;
+            return best.Inverse
+                   ? CreateExpression($"1 / {invP}")
+                   : best.Expression;
         }
 
         internal static ExpressionSyntax CreateExpression(string str)
@@ -364,7 +368,7 @@ namespace BTCPayServer.Rating
             string _ExchangeName = null;
 
             public List<RateRulesErrors> Errors = new List<RateRulesErrors>();
-            const int MaxNestedCount = 6;
+            const int MaxNestedCount = 8;
             public override SyntaxNode VisitIdentifierName(IdentifierNameSyntax node)
             {
                 if (CurrencyPair.TryParse(node.Identifier.ValueText, out var currentPair))

BTCPayServer/Services/Fees/NBxplorerFeeProvider.cs

@@ -39,6 +39,8 @@ namespace BTCPayServer.Services.Fees
         ExplorerClient _ExplorerClient;
         public async Task<FeeRate> GetFeeRateAsync()
         {
+            if (!_ExplorerClient.Network.SupportEstimatesSmartFee)
+                return _Factory.Fallback;
             try
             {
                 return (await _ExplorerClient.GetFeeRateAsync(_Factory.BlockTarget).ConfigureAwait(false)).FeeRate;

BTCPayServer/Services/Invoices/InvoiceEntity.cs

@@ -314,6 +314,7 @@ namespace BTCPayServer.Services.Invoices
         }
         public bool ExtendedNotifications { get; set; }
         public List<InvoiceEventData> Events { get; internal set; }
+        public double PaymentTolerance { get; set; }
 
         public bool IsExpired()
         {
@@ -336,6 +337,8 @@ namespace BTCPayServer.Services.Invoices
                 Currency = ProductInformation.Currency,
                 Flags = new Flags() { Refundable = Refundable }
             };
+
+            dto.Url = ServerUrl.WithTrailingSlash() + $"invoice?id=" + Id;
             dto.CryptoInfo = new List<NBitpayClient.InvoiceCryptoInfo>();
             foreach (var info in this.GetPaymentMethods(networkProvider))
             {
@@ -358,14 +361,13 @@ namespace BTCPayServer.Services.Invoices
                 {
                     { ProductInformation.Currency, (double)cryptoInfo.Rate }
                 };
-
+                var paymentId = info.GetId();
                 var scheme = info.Network.UriScheme;
-                var cryptoSuffix = cryptoInfo.CryptoCode == "BTC" ? "" : "/" + cryptoInfo.CryptoCode;
-                cryptoInfo.Url = ServerUrl.WithTrailingSlash() + $"invoice{cryptoSuffix}?id=" + Id;
+                cryptoInfo.Url = ServerUrl.WithTrailingSlash() + $"i/{paymentId}/{Id}";
 
-
-                if (info.GetId().PaymentType == PaymentTypes.BTCLike)
+                if (paymentId.PaymentType == PaymentTypes.BTCLike)
                 {
+                    var cryptoSuffix = cryptoInfo.CryptoCode == "BTC" ? "" : "/" + cryptoInfo.CryptoCode;
                     cryptoInfo.PaymentUrls = new NBitpayClient.InvoicePaymentUrls()
                     {
                         BIP72 = $"{scheme}:{cryptoInfo.Address}?amount={cryptoInfo.Due}&r={ServerUrl.WithTrailingSlash() + ($"i/{Id}{cryptoSuffix}")}",
@@ -374,7 +376,7 @@ namespace BTCPayServer.Services.Invoices
                         BIP21 = $"{scheme}:{cryptoInfo.Address}?amount={cryptoInfo.Due}",
                     };
                 }
-                var paymentId = info.GetId();
+                
                 if (paymentId.PaymentType == PaymentTypes.LightningLike)
                 {
                     cryptoInfo.PaymentUrls = new NBitpayClient.InvoicePaymentUrls()
@@ -385,7 +387,6 @@ namespace BTCPayServer.Services.Invoices
 #pragma warning disable CS0618
                 if (info.CryptoCode == "BTC" && paymentId.PaymentType == PaymentTypes.BTCLike)
                 {
-                    dto.Url = cryptoInfo.Url;
                     dto.BTCPrice = cryptoInfo.Price;
                     dto.Rate = cryptoInfo.Rate;
                     dto.ExRates = cryptoInfo.ExRates;
@@ -403,7 +404,6 @@ namespace BTCPayServer.Services.Invoices
 
             dto.Token = Encoders.Base58.EncodeData(RandomUtils.GetBytes(16)); //No idea what it is useful for
             dto.Guid = Guid.NewGuid().ToString();
-            dto.Url = dto.CryptoInfo[0].Url;
             dto.ExceptionStatus = ExceptionStatus == null ? new JValue(false) : new JValue(ExceptionStatus);
             return dto;
         }
@@ -524,6 +524,10 @@ namespace BTCPayServer.Services.Invoices
         /// Total amount of network fee to pay to the invoice
         /// </summary>
         public Money NetworkFee { get; set; }
+        /// <summary>
+        /// Minimum required to be paid in order to accept invocie as paid
+        /// </summary>
+        public Money MinimumTotalDue { get; set; }
     }
 
     public class PaymentMethod
@@ -672,6 +676,7 @@ namespace BTCPayServer.Services.Invoices
             accounting.Due = Money.Max(accounting.TotalDue - accounting.Paid, Money.Zero);
             accounting.DueUncapped = accounting.TotalDue - accounting.Paid;
             accounting.NetworkFee = accounting.TotalDue - totalDueNoNetworkCost;
+            accounting.MinimumTotalDue = Money.Max(Money.Satoshis(1), Money.Satoshis(accounting.TotalDue.Satoshi * (1.0m - ((decimal)ParentEntity.PaymentTolerance / 100.0m))));
             return accounting;
         }
 

BTCPayServer/Services/Invoices/InvoiceRepository.cs

@@ -436,6 +436,18 @@ namespace BTCPayServer.Services.Invoices
                     query = query.Where(i => statusSet.Contains(i.Status));
                 }
 
+                if(queryObject.Unusual != null)
+                {
+                    var unused = queryObject.Unusual.Value;
+                    query = query.Where(i => unused == (i.Status == "invalid" || i.ExceptionStatus != null));
+                }
+
+                if (queryObject.ExceptionStatus != null && queryObject.ExceptionStatus.Length > 0)
+                {
+                    var exceptionStatusSet = queryObject.ExceptionStatus.Select(s => NormalizeExceptionStatus(s)).ToHashSet();
+                    query = query.Where(i => exceptionStatusSet.Contains(i.ExceptionStatus));
+                }
+
                 query = query.OrderByDescending(q => q.Created);
 
                 if (queryObject.Skip != null)
@@ -451,6 +463,29 @@ namespace BTCPayServer.Services.Invoices
 
         }
 
+        private string NormalizeExceptionStatus(string status)
+        {
+            status = status.ToLowerInvariant();
+            switch (status)
+            {
+                case "paidover":
+                case "over":
+                case "overpaid":
+                    status = "paidOver";
+                    break;
+                case "paidlate":
+                case "late":
+                    status = "paidLate";
+                    break;
+                case "paidpartial":
+                case "underpaid":
+                case "partial":
+                    status = "paidPartial";
+                    break;
+            }
+            return status;
+        }
+
         public async Task AddRefundsAsync(string invoiceId, TxOut[] outputs, Network network)
         {
             if (outputs.Length == 0)
@@ -614,10 +649,18 @@ namespace BTCPayServer.Services.Invoices
             get; set;
         }
 
+        public bool? Unusual { get; set; }
+
         public string[] Status
         {
             get; set;
         }
+
+        public string[] ExceptionStatus
+        {
+            get; set;
+        }
+
         public string InvoiceId
         {
             get;

BTCPayServer/Services/Mails/EmailSender.cs

@@ -24,8 +24,8 @@ namespace BTCPayServer.Services.Mails
         }
         public async Task SendEmailAsync(string email, string subject, string message)
         {
-            var settings = await _Repository.GetSettingAsync<EmailSettings>();
-            if (settings == null)
+            var settings = await _Repository.GetSettingAsync<EmailSettings>() ?? new EmailSettings();
+            if (!settings.IsComplete())
             {
                 Logs.Configuration.LogWarning("Should have sent email, but email settings are not configured");
                 return;
@@ -36,8 +36,8 @@ namespace BTCPayServer.Services.Mails
 
         public async Task SendMailCore(string email, string subject, string message)
         {
-            var settings = await _Repository.GetSettingAsync<EmailSettings>();
-            if (settings == null)
+            var settings = await _Repository.GetSettingAsync<EmailSettings>() ?? new EmailSettings();
+            if (!settings.IsComplete())
                 throw new InvalidOperationException("Email settings not configured");
             var smtp = settings.CreateSmtpClient();
             MailMessage mail = new MailMessage(settings.From, email, subject, message);

BTCPayServer/Services/Mails/EmailSettings.cs

@@ -40,6 +40,18 @@ namespace BTCPayServer.Services.Mails
             get; set;
         }
 
+        public bool IsComplete()
+        {
+            SmtpClient smtp = null;
+            try
+            {
+                smtp = CreateSmtpClient();
+                return true;
+            }
+            catch { }
+            return false;
+        }
+
         public SmtpClient CreateSmtpClient()
         {
             SmtpClient client = new SmtpClient(Server, Port.Value);

BTCPayServer/Views/Invoice/ListInvoices.cshtml

@@ -20,14 +20,16 @@
                 <div id="help" class="collapse text-left">
                     <p>
                         You can search for invoice Id, deposit address, price, order id, store id, any buyer information and any product information.<br />
-                        You can also apply filters to your search by searching for `filtername:value`, here is a list of supported filters
+                        You can also apply filters to your search by searching for <code>filtername:value</code>, here is a list of supported filters
                     </p>
                     <ul>
-                        <li><b>storeid:id</b> for filtering a specific store</li>
-                        <li><b>status:(expired|invalid|complete|confirmed|paid|new)</b> for filtering a specific status</li>
+                        <li><code>storeid:id</code> for filtering a specific store</li>
+                        <li><code>status:(expired|invalid|complete|confirmed|paid|new)</code> for filtering a specific status</li>
+                        <li><code>exceptionstatus:(paidover|paidlate|paidpartial)</code> for filtering a specific exception state</li>
+                        <li><code>unusual:(true|false)</code> for filtering invoices which might requires merchant attention (those invalid or with an exceptionstatus)</li>
                     </ul>
                     <p>
-                        If you want two confirmed and complete invoices, duplicate the filter: `status:confirmed status:complete`.
+                        If you want two confirmed and complete invoices, duplicate the filter: <code>status:confirmed status:complete</code>.
                     </p>
                 </div>
                 <div class="form-group">
@@ -95,7 +97,7 @@
                             }
                             <td style="text-align:right">@invoice.AmountCurrency</td>
                             <td style="text-align:right">
-                                @if(invoice.Status == "new")
+                                @if(invoice.ShowCheckout)
                                 {
                                     <a asp-action="Checkout" asp-route-invoiceId="@invoice.InvoiceId">Checkout</a> <span>-</span>
                                 }<a asp-action="Invoice" asp-route-invoiceId="@invoice.InvoiceId">Details</a>

BTCPayServer/Views/Stores/Rates.cshtml

@@ -93,7 +93,19 @@
                             X_X = gdax(X_X);
                         </code>
                     </pre>
-                    <p>With <code>DOGE_USD</code> will be expanded to <code>bittrex(DOGE_BTC) * gdax(BTC_USD)</code>. And <code>DOGE_CAD</code> will be expanded to <code>bittrex(DOGE_BTC) * quadrigacx(BTC_CAD)</code></p>
+                    <p>With <code>DOGE_USD</code> will be expanded to <code>bittrex(DOGE_BTC) * gdax(BTC_USD)</code>. And <code>DOGE_CAD</code> will be expanded to <code>bittrex(DOGE_BTC) * quadrigacx(BTC_CAD)</code>. <br />
+                    However, we advise you to write it that way to increase coverage so that <code>DOGE_BTC</code> is also supported:</p>
+                    <pre>
+                        <code>
+                            DOGE_X = DOGE_BTC * BTC_X
+                            DOGE_BTC = bittrex(DOGE_BTC)
+                            X_CAD = quadrigacx(X_CAD);
+                            X_X = gdax(X_X);
+                        </code>
+                    </pre>
+                    <p>It is worth noting that the inverses of those pairs are automatically supported as well.<br />
+                    It means that the rule <code>USD_DOGE = 1 / DOGE_USD</code> implicitely exists.</p>
+
                 </div>
                 <div class="form-group">
                     <label asp-for="Script"></label>

BTCPayServer/Views/Stores/UpdateStore.cshtml

@@ -44,6 +44,11 @@
                 <input asp-for="MonitoringExpiration" class="form-control" />
                 <span asp-validation-for="MonitoringExpiration" class="text-danger"></span>
             </div>
+            <div class="form-group">
+                <label asp-for="PaymentTolerance"></label>
+                <input asp-for="PaymentTolerance" class="form-control" />
+                <span asp-validation-for="PaymentTolerance" class="text-danger"></span>
+            </div>
             <div class="form-group">
                 <label asp-for="SpeedPolicy"></label>
                 <select asp-for="SpeedPolicy" class="form-control">