fix: Briefe Kontaktauswahl

LehrerApp.Desktop.Tests/CreateLetterDialogViewModelTests.cs

@@ -191,6 +191,49 @@ public sealed class CreateLetterDialogViewModelTests : IDisposable
         Assert.True(vm.Generate(output));
     }
 
+    [Fact]
+    public void AddressPreview_FolgtDemGewaehltenKontaktUndAktualisiertSichBeimWechsel()
+    {
+        var student = new Student
+        {
+            FirstName = "Lena", LastName = "Beispiel",
+            Contacts =
+            [
+                new Contact { Name = "Frau Beispiel", Relation = "Mutter", Street = "Erste Str. 1", PostalCode = "11111", City = "Erststadt" },
+                new Contact { Name = "Herr Beispiel", Relation = "Vater", Street = "Zweite Str. 2", PostalCode = "22222", City = "Zweitstadt" },
+            ],
+        };
+        var vm = Build(student, StoreWithTemplate(new PlaceholderDefinition("Anrede", PlaceholderType.Text, true)));
+
+        Assert.Equal(2, vm.Contacts.Count);
+        Assert.Contains("Frau Beispiel", vm.AddressPreview);
+        Assert.Contains("Erste Str. 1", vm.AddressPreview);
+
+        vm.SelectedContact = vm.Contacts.Single(c => c.Model.Name == "Herr Beispiel");
+
+        Assert.Contains("Herr Beispiel", vm.AddressPreview);
+        Assert.Contains("Zweite Str. 2", vm.AddressPreview);
+        Assert.DoesNotContain("Frau Beispiel", vm.AddressPreview);
+    }
+
+    [Fact]
+    public void SelectContactDialog_StartetBeimAktuellenKontaktUndAktualisiertVorschau()
+    {
+        var contacts = new List<LetterContactChoice>
+        {
+            new(new Contact { Name = "Frau Beispiel", Street = "Erste Str. 1", PostalCode = "11111", City = "Erststadt" }),
+            new(new Contact { Name = "Herr Beispiel", Street = "Zweite Str. 2", PostalCode = "22222", City = "Zweitstadt" }),
+        };
+        var dialogVm = new SelectContactDialogViewModel(contacts, contacts[1]);
+
+        Assert.Same(contacts[1], dialogVm.SelectedContact);
+        Assert.Contains("Zweite Str. 2", dialogVm.AddressPreview);
+
+        dialogVm.SelectedContact = contacts[0];
+
+        Assert.Contains("Erste Str. 1", dialogVm.AddressPreview);
+    }
+
     private CreateLetterDialogViewModel Build(Student student, TemplateStore store) =>
         new(student, store, new QuestTemplateRenderer(), new FakeMemberships([]), new FakeGroups([]));