feat(usability): explain booking fields and validate decimal input (U06)

tests/Duempelkas.Tests/BookingFormTests.cs

@@ -0,0 +1,51 @@
+using Bunit;
+using Duempelkas.App.Components.Dialogs;
+using Duempelkas.App.Services;
+using Duempelkas.App.Services.Models;
+using Duempelkas.Domain.Enums;
+using Duempelkas.Infrastructure.Services;
+using Microsoft.Extensions.DependencyInjection;
+using Xunit;
+
+namespace Duempelkas.Tests;
+
+public class BookingFormTests
+{
+    [Fact]
+    public void Form_ExplainsMissingFields_AndDoesNotRoundInvalidInput()
+    {
+        using var context = new BunitContext();
+        context.Services.AddSingleton<IEntryService>(new EntryService(null!));
+        var dialog = context.Render<AddEntryDialog>(p => p.Add(x => x.AccountName, "Barkasse"));
+        Assert.Contains("Barkasse", dialog.Find("h5").TextContent);
+        Assert.Contains("Bitte beschreiben", dialog.Markup);
+        Assert.True(dialog.Find("button.btn-success").HasAttribute("disabled"));
+        dialog.Find("#entry-title").Input("Porto");
+        dialog.Find("#entry-amount").Input("12,501");
+        Assert.Equal("12,501", dialog.Find("#entry-amount").GetAttribute("value"));
+        Assert.True(dialog.Find("button.btn-success").HasAttribute("disabled"));
+        dialog.Find("#entry-amount").Input("-12,50");
+        Assert.True(dialog.Find("button.btn-success").HasAttribute("disabled"));
+        dialog.Find("#entry-amount").Input("12,50");
+        Assert.False(dialog.Find("button.btn-success").HasAttribute("disabled"));
+        dialog.Find("#entry-date").Input("");
+        Assert.True(dialog.Find("button.btn-success").HasAttribute("disabled"));
+        Assert.Contains("Bitte ein gültiges Datum", dialog.Markup);
+        dialog.Find("#entry-date").Input("2026-01-02");
+        Assert.False(dialog.Find("button.btn-success").HasAttribute("disabled"));
+    }
+
+    [Fact]
+    public void Edit_ShowsFixedTypeAndCorrectionPath_AndRerenderKeepsInput()
+    {
+        using var context = new BunitContext();
+        context.Services.AddSingleton<IEntryService>(new EntryService(null!));
+        var entry = new EntryDto(1, 1, "2026-001", EntryType.Expense, new(2026, 1, 1), "Porto", 4.20m, false, false, null, null, null);
+        var dialog = context.Render<AddEntryDialog>(p => p.Add(x => x.EditEntry, entry));
+        Assert.Contains("Ausgabe", dialog.Markup);
+        Assert.Contains("mit der richtigen Art neu erfassen", dialog.Markup);
+        dialog.Find("#entry-title").Input("Korrigierter Text");
+        dialog.Render(p => p.Add(x => x.EditEntry, entry));
+        Assert.Equal("Korrigierter Text", dialog.Find("#entry-title").GetAttribute("value"));
+    }
+}

tests/Duempelkas.Tests/BookingInputTests.cs

@@ -0,0 +1,35 @@
+using Duempelkas.App.Services;
+using Xunit;
+
+namespace Duempelkas.Tests;
+
+public class BookingInputTests
+{
+    [Theory]
+    [InlineData("12,50", true)]
+    [InlineData("12.50", true)]
+    [InlineData(" 12,50 ", true)]
+    [InlineData("12,500", false)]
+    [InlineData("-12,50", false)]
+    [InlineData("1.234,56", false)]
+    [InlineData("1,234.56", false)]
+    [InlineData("12,50 €", false)]
+    [InlineData("0", false)]
+    [InlineData("", false)]
+    [InlineData("9999999999999999999999999999999999999", false)]
+    public void DecimalInput_HasExplicitRules(string text, bool valid)
+    {
+        Assert.Equal(valid, BookingInput.TryAmount(text, out var amount));
+        if (valid) Assert.Equal(12.50m, amount);
+    }
+
+    [Fact]
+    public void ServiceValidation_RejectsInvalidData()
+    {
+        Assert.Throws<ArgumentException>(() => BookingInput.Validate(default, "Test", 1m));
+        Assert.Throws<ArgumentException>(() => BookingInput.Validate(DateTime.Today, " ", 1m));
+        Assert.Throws<ArgumentException>(() => BookingInput.Validate(DateTime.Today, "Test", -1m));
+        Assert.Throws<ArgumentException>(() => BookingInput.Validate(DateTime.Today, "Test", 1.001m));
+        Assert.Equal(default, BookingInput.Date("2026-02-30"));
+    }
+}

tests/Duempelkas.Tests/YearNavigationTests.cs

@@ -42,9 +42,9 @@ public class YearNavigationTests
         page.WaitForElement(".summary-section");
         page.FindAll("button").Single(b => b.TextContent.Contains("Einnahme oder Ausgabe erfassen")).Click();
         var dialog = page.FindComponent<AddEntryDialog>();
-        dialog.Find("input[type=date]").Change("2026-01-02");
-        dialog.Find("input[type=text]").Change("Außerhalb");
-        dialog.Find("input[type=number]").Change("12.50");
+        dialog.Find("input[type=date]").Input("2026-01-02");
+        dialog.Find("#entry-title").Input("Außerhalb");
+        dialog.Find("#entry-amount").Input("12.50");
         Assert.Contains("außerhalb", dialog.Markup);
         Assert.True(dialog.Find("button.btn-success").HasAttribute("disabled"));
         dialog.Find("input[type=checkbox]").Change(true);