Create Json converter to parse mandate payment specific responses

src/Mollie.Api/Framework/Factories/MandateResponseFactory.cs

@@ -0,0 +1,25 @@
+using System;
+using Mollie.Api.Models.Mandate.Response;
+using Mollie.Api.Models.Mandate.Response.PaymentSpecificParameters;
+using Mollie.Api.Models.Payment;
+
+namespace Mollie.Api.Framework.Factories;
+
+internal class MandateResponseFactory {
+    public MandateResponse Create(string? paymentMethod) {
+            if (string.IsNullOrEmpty(paymentMethod)) {
+                return Activator.CreateInstance<MandateResponse>();
+            }
+
+            switch (paymentMethod) {
+                case PaymentMethod.PayPal:
+                    return Activator.CreateInstance<PayPalMandateResponse>();
+                case PaymentMethod.DirectDebit:
+                    return Activator.CreateInstance<SepaDirectDebitMandateResponse>();
+                case PaymentMethod.CreditCard:
+                    return Activator.CreateInstance<CreditCardMandateResponse>();
+                default:
+                    return Activator.CreateInstance<MandateResponse>();
+            }
+        }
+}

src/Mollie.Api/Framework/JsonConverterService.cs

@@ -40,6 +40,8 @@ private JsonSerializerSettings CreateDefaultJsonDeserializerSettings() {
                     new BalanceReportResponseJsonConverter(new BalanceReportResponseFactory()),
                     // Add a special converter for the balance transaction responses, because we need to create specific classes based on the transaction type
                     new BalanceTransactionJsonConverter(new BalanceTransactionFactory()),
+                    // Add a special converter for mandate responses, because we need to create specific classes based on the payment method
+                    new MandateResponseConverter(new MandateResponseFactory())
                 }
             };
         }

src/Mollie.Api/JsonConverters/MandateResponseConverter.cs

@@ -0,0 +1,31 @@
+using System;
+using Mollie.Api.Framework.Factories;
+using Mollie.Api.Models.Mandate.Response;
+using Newtonsoft.Json.Linq;
+
+namespace Mollie.Api.JsonConverters;
+
+internal class MandateResponseConverter : JsonCreationConverter<MandateResponse> {
+    private readonly MandateResponseFactory _mandateResponseFactory;
+
+    public MandateResponseConverter(MandateResponseFactory mandateResponseFactory) {
+        _mandateResponseFactory = mandateResponseFactory;
+    }
+
+    protected override MandateResponse Create(Type objectType, JObject jObject) {
+        string? paymentMethod = GetPaymentMethod(jObject);
+
+        return _mandateResponseFactory.Create(paymentMethod);
+    }
+
+    private string? GetPaymentMethod(JObject jObject) {
+        if (FieldExists("method", jObject)) {
+            string paymentMethodValue = (string) jObject["method"]!;
+            if (!string.IsNullOrEmpty(paymentMethodValue)) {
+                return paymentMethodValue;
+            }
+        }
+
+        return null;
+    }
+}

src/Mollie.Api/Models/Mandate/Response/PaymentSpecificParameters/PayPalMandateResponse.cs

@@ -1,6 +1,6 @@
 namespace Mollie.Api.Models.Mandate.Response.PaymentSpecificParameters;
 
-public record PayPalMandateResponse {
+public record PayPalMandateResponse : MandateResponse {
     public required PayPalMandateResponseDetails Details { get; set; }
 }
 

tests/Mollie.Tests.Integration/Api/MandateTests.cs

@@ -9,7 +9,9 @@
 using Mollie.Api.Models.Mandate.Request;
 using Mollie.Api.Models.Mandate.Request.PaymentSpecificParameters;
 using Mollie.Api.Models.Mandate.Response;
+using Mollie.Api.Models.Mandate.Response.PaymentSpecificParameters;
 using Mollie.Api.Models.Payment;
+using Mollie.Api.Models.Payment.Response.PaymentSpecificParameters;
 using Mollie.Tests.Integration.Framework;
 
 namespace Mollie.Tests.Integration.Api;
@@ -56,12 +58,12 @@ public async Task ListMandatesNeverReturnsMoreCustomersThenTheNumberOfRequestedM
     }
 
     [DefaultRetryFact]
-    public async Task CanCreateMandate() {
+    public async Task CanCreateSepaDirectDebitMandate() {
         // We can only test this if there are customers
         ListResponse<CustomerResponse> customers = await _customerClient.GetCustomerListAsync();
         if (customers.Count > 0) {
             // If: We create a new mandate request
-            SepaDirectDebitMandateRequest mandateRequest = new SepaDirectDebitMandateRequest {
+            SepaDirectDebitMandateRequest mandateRequest = new () {
                 ConsumerAccount = "NL26ABNA0516682814",
                 ConsumerName = "John Doe",
                 Method = PaymentMethod.DirectDebit
@@ -71,8 +73,34 @@ public async Task CanCreateMandate() {
             MandateResponse mandateResponse = await _mandateClient.CreateMandateAsync(customers.Items.First().Id, mandateRequest);
 
             // Then: Make sure we created a new mandate
-            mandateResponse.Details!.ConsumerAccount.Should().Be(mandateRequest.ConsumerAccount);
-            mandateResponse.Details.ConsumerName.Should().Be(mandateRequest.ConsumerName);
+            mandateResponse.Should().BeOfType<SepaDirectDebitMandateResponse>();
+            var sepaDirectDebitResponse = (SepaDirectDebitMandateResponse)mandateResponse;
+            sepaDirectDebitResponse.Details.ConsumerAccount.Should().Be(mandateRequest.ConsumerAccount);
+            sepaDirectDebitResponse.Details.ConsumerName.Should().Be(mandateRequest.ConsumerName);
+        }
+    }
+
+    [DefaultRetryFact]
+    public async Task CanCreatePayPalMandate() {
+        // We can only test this if there are customers
+        ListResponse<CustomerResponse> customers = await _customerClient.GetCustomerListAsync();
+        if (customers.Count > 0) {
+            // If: We create a new mandate request
+            PayPalMandateRequest mandateRequest = new () {
+                ConsumerName = "John Doe",
+                Method = PaymentMethod.PayPal,
+                PaypalBillingAgreementId = "paypal-billing-agreement-id",
+                ConsumerEmail = "[email protected]"
+            };
+
+            // When: We send the mandate request
+            MandateResponse mandateResponse = await _mandateClient.CreateMandateAsync(customers.Items.First().Id, mandateRequest);
+
+            // Then: Make sure we created a new mandate
+            mandateResponse.Should().BeOfType<PayPalMandateResponse>();
+            var paypalMandateResponse = (PayPalMandateResponse)mandateResponse;
+            paypalMandateResponse.Details.ConsumerAccount.Should().Be(mandateRequest.ConsumerEmail);
+            paypalMandateResponse.Details.ConsumerName.Should().Be(mandateRequest.ConsumerName);
         }
     }