Klausurauswertung (1.5) — Kapitel 1 damit vollständig

Neuer Dialog ExamEvaluationDialog, erreichbar über "Auswertung" im
Klausuren-Tab (Button + Kontextmenü bei ausgewählter Klausur):

- Notenspiegel als Balkendiagramm, Durchschnitt (via bestehendes
  GradingService.WeightedAverage), Median, sowie ein Schwellenwert-
  Anteil ("< 5/4 Punkte" bei Punktesystem, "nicht ausreichend 5/6"
  bei Notensystem 1–6).
- Aufgabenanalyse: durchschnittlicher Erfüllungsgrad je Aufgabe,
  auffällig schwache (Ø < 50 %) rot markiert.
- Notenschlüssel verschieben: gleicher Editor wie im Klausur-Dialog,
  Änderungen wirken sich sofort im Notenspiegel aus; erst
  "Übernehmen" schreibt sie in die Klausur zurück.
- CSV-Export direkt im Dialog, analog zum bestehenden JSON-Export der
  Kompetenzkataloge — ohne die noch fehlende Export-Infrastruktur aus
  Kapitel 11 vorwegzunehmen.
- Abwesende werden konsequent aus allen Statistiken ausgeschlossen
  (löst den in 1.4.3 offen gelassenen Punkt ein).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

LehrerApp.Desktop/ViewModels/Groups/ExamEvaluationViewModels.cs

@@ -0,0 +1,258 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using LehrerApp.Core.Interfaces;
+using LehrerApp.Core.Models;
+using LehrerApp.Core.Services;
+using System.Collections.ObjectModel;
+using System.Globalization;
+using System.Text;
+
+namespace LehrerApp.Desktop.ViewModels.Groups;
+
+// ── Klausurauswertung (1.5) ───────────────────────────────────────────────────
+
+public partial class ExamEvaluationDialogViewModel : ObservableObject
+{
+    private readonly IExamRepository _exams;
+    private readonly IExamResultRepository _results;
+    private readonly GradingService _grading;
+    private readonly Exam _exam;
+    private readonly GradingSystem _gradingSystem;
+    private readonly double _examMaxPoints;
+    private List<ExamResult> _gradedResults = [];
+
+    public string ExamTitle => _exam.Title;
+    public string ExamDateLabel => _exam.Date.ToString("dd.MM.yyyy");
+
+    [ObservableProperty] private int _gradedCount;
+    [ObservableProperty] private int _absentCount;
+    [ObservableProperty] private string _averageDisplay = "–";
+    [ObservableProperty] private string _medianDisplay = "–";
+    [ObservableProperty] private string _belowThresholdLabel1 = "";
+    [ObservableProperty] private string _belowThresholdDisplay1 = "";
+    [ObservableProperty] private string _belowThresholdLabel2 = "";
+    [ObservableProperty] private string _belowThresholdDisplay2 = "";
+    [ObservableProperty] private string _gradingKeyValidation = "";
+    [ObservableProperty] private string _gradingKeyStatus = "";
+
+    public ObservableCollection<GradeBarItem> GradeDistribution { get; } = [];
+    public ObservableCollection<TaskAnalysisItem> TaskAnalysis { get; } = [];
+    public ObservableCollection<GradingKeyEntryEditItem> GradingKeyEntries { get; } = [];
+
+    public ExamEvaluationDialogViewModel(IExamRepository exams, IExamResultRepository results,
+        GradingService grading, Exam exam, GradingSystem gradingSystem)
+    {
+        _exams = exams; _results = results; _grading = grading; _exam = exam;
+        _gradingSystem = gradingSystem;
+        _examMaxPoints = exam.Tasks.Sum(t => t.MaxPoints);
+
+        foreach (var e in exam.GradingKey.OrderByDescending(e => e.MinPercent))
+            AddGradingKeyRowInternal(e.Grade, e.MinPercent);
+
+        LoadResults();
+    }
+
+    private void LoadResults()
+    {
+        var all = _results.GetByExam(_exam.Id);
+        AbsentCount = all.Count(r => r.Absent);
+        _gradedResults = all.Where(r => !r.Absent).ToList();
+        GradedCount = _gradedResults.Count;
+        Recompute();
+    }
+
+    // ── Notenschlüssel-Editor (1.5.3) ────────────────────────────────────────
+
+    [RelayCommand]
+    private void AddGradingKeyRow() => AddGradingKeyRowInternal("", 0);
+
+    private void AddGradingKeyRowInternal(string grade, double minPercent)
+    {
+        var item = new GradingKeyEntryEditItem
+        {
+            Grade = grade,
+            MinPercent = minPercent,
+            OnChanged = OnGradingKeyRowChanged,
+            OnRemove = RemoveGradingKeyRow,
+        };
+        GradingKeyEntries.Add(item);
+        RecomputeGradingKeyAbsolutes();
+    }
+
+    private void OnGradingKeyRowChanged()
+    {
+        RecomputeGradingKeyAbsolutes();
+        Recompute();
+    }
+
+    private void RemoveGradingKeyRow(GradingKeyEntryEditItem item)
+    {
+        GradingKeyEntries.Remove(item);
+        RecomputeGradingKeyAbsolutes();
+        Recompute();
+    }
+
+    private void RecomputeGradingKeyAbsolutes()
+    {
+        foreach (var e in GradingKeyEntries)
+            e.AbsolutePointsDisplay = _examMaxPoints <= 0
+                ? "–"
+                : $"ab {(e.MinPercent / 100.0 * _examMaxPoints).ToString("0.##", CultureInfo.InvariantCulture)} " +
+                  $"von {_examMaxPoints.ToString("0.##", CultureInfo.InvariantCulture)} Punkten";
+    }
+
+    private List<GradingKeyEntry> BuildCurrentGradingKey() => GradingKeyEntries
+        .Select(e => new GradingKeyEntry { Grade = e.Grade.Trim(), MinPercent = e.MinPercent })
+        .OrderByDescending(e => e.MinPercent)
+        .ToList();
+
+    [RelayCommand]
+    private void ApplyGradingKey()
+    {
+        var key = BuildCurrentGradingKey();
+        var error = _grading.ValidateGradingKey(key);
+        if (error is not null) { GradingKeyValidation = error; GradingKeyStatus = ""; return; }
+        GradingKeyValidation = "";
+        _exam.GradingKey = key;
+        _exams.Save(_exam);
+        GradingKeyStatus = "Notenschlüssel für diese Klausur übernommen.";
+    }
+
+    // ── Auswertung neu berechnen ──────────────────────────────────────────────
+
+    private void Recompute()
+    {
+        var currentKey = BuildCurrentGradingKey();
+        GradingKeyValidation = _grading.ValidateGradingKey(currentKey) ?? "";
+
+        var grades = _gradedResults
+            .Select(r => _grading.CalculateGrade(r.TotalPoints, _examMaxPoints, currentKey))
+            .ToList();
+
+        GradeDistribution.Clear();
+        var counts = grades.GroupBy(g => g).ToDictionary(g => g.Key, g => g.Count());
+        var maxCount = counts.Count == 0 ? 0 : counts.Values.Max();
+        foreach (var entry in currentKey.OrderByDescending(e => e.MinPercent))
+        {
+            counts.TryGetValue(entry.Grade, out var count);
+            GradeDistribution.Add(new GradeBarItem(entry.Grade, count, grades.Count, maxCount));
+        }
+
+        AverageDisplay = grades.Count == 0
+            ? "–"
+            : _grading.WeightedAverage(grades.Select(g => (Grade: g, Weight: 1.0)).ToList())
+                       .ToString("0.00", CultureInfo.InvariantCulture);
+
+        var numeric = grades.Select(g => int.TryParse(g, out var n) ? (int?)n : null)
+                             .Where(n => n.HasValue).Select(n => n!.Value)
+                             .OrderBy(n => n).ToList();
+        MedianDisplay = numeric.Count == 0 ? "–" : ComputeMedian(numeric).ToString("0.##", CultureInfo.InvariantCulture);
+
+        if (_gradingSystem == GradingSystem.Points0To15)
+        {
+            BelowThresholdLabel1   = "Anteil < 5 Punkte";
+            BelowThresholdDisplay1 = Percent(numeric.Count(n => n < 5), numeric.Count);
+            BelowThresholdLabel2   = "Anteil < 4 Punkte";
+            BelowThresholdDisplay2 = Percent(numeric.Count(n => n < 4), numeric.Count);
+        }
+        else
+        {
+            BelowThresholdLabel1   = "Anteil nicht ausreichend (Note 5/6)";
+            BelowThresholdDisplay1 = Percent(numeric.Count(n => n >= 5), numeric.Count);
+            BelowThresholdLabel2   = "";
+            BelowThresholdDisplay2 = "";
+        }
+
+        RecomputeTaskAnalysis();
+    }
+
+    private void RecomputeTaskAnalysis()
+    {
+        TaskAnalysis.Clear();
+        var tasks = _exam.Tasks.OrderBy(t => t.Nr).ToList();
+        for (var i = 0; i < tasks.Count; i++)
+        {
+            var task = tasks[i];
+            var achieved = _gradedResults.Where(r => i < r.Points.Count).Select(r => r.Points[i]).ToList();
+            var avgPercent = task.MaxPoints <= 0 || achieved.Count == 0
+                ? 0
+                : achieved.Average() / task.MaxPoints * 100.0;
+            TaskAnalysis.Add(new TaskAnalysisItem(task.Nr, task.Title, avgPercent));
+        }
+    }
+
+    private static double ComputeMedian(List<int> sorted)
+    {
+        var n = sorted.Count;
+        return n % 2 == 1 ? sorted[n / 2] : (sorted[n / 2 - 1] + sorted[n / 2]) / 2.0;
+    }
+
+    private static string Percent(int count, int total) =>
+        total == 0 ? "–" : $"{(count * 100.0 / total).ToString("0.#", CultureInfo.InvariantCulture)} %";
+
+    // ── Export (1.5.4) ────────────────────────────────────────────────────────
+
+    public string ExportCsv()
+    {
+        var sb = new StringBuilder();
+        sb.AppendLine($"Klausur;{_exam.Title}");
+        sb.AppendLine($"Datum;{_exam.Date:dd.MM.yyyy}");
+        sb.AppendLine();
+        sb.AppendLine("Notenspiegel");
+        sb.AppendLine("Note;Anzahl;Anteil");
+        foreach (var g in GradeDistribution)
+            sb.AppendLine($"{g.Grade};{g.Count};{Percent(g.Count, GradedCount)}");
+        sb.AppendLine();
+        sb.AppendLine($"Durchschnitt;{AverageDisplay}");
+        sb.AppendLine($"Median;{MedianDisplay}");
+        if (!string.IsNullOrEmpty(BelowThresholdLabel1)) sb.AppendLine($"{BelowThresholdLabel1};{BelowThresholdDisplay1}");
+        if (!string.IsNullOrEmpty(BelowThresholdLabel2)) sb.AppendLine($"{BelowThresholdLabel2};{BelowThresholdDisplay2}");
+        sb.AppendLine($"Bewertet;{GradedCount}");
+        sb.AppendLine($"Abwesend;{AbsentCount}");
+        sb.AppendLine();
+        sb.AppendLine("Aufgabenanalyse");
+        sb.AppendLine("Aufgabe;Ø Erfüllungsgrad;Auffällig schwach");
+        foreach (var t in TaskAnalysis)
+            sb.AppendLine($"{t.Label};{t.AvgPercentDisplay};{(t.IsWeak ? "ja" : "")}");
+        return sb.ToString();
+    }
+}
+
+// ── Notenspiegel-Balken ────────────────────────────────────────────────────
+
+public class GradeBarItem
+{
+    public string Grade { get; }
+    public int Count { get; }
+    public string CountDisplay { get; }
+    public double BarWidth { get; }
+
+    public GradeBarItem(string grade, int count, int totalGraded, int maxCount)
+    {
+        Grade = grade;
+        Count = count;
+        var percent = totalGraded == 0 ? 0 : count * 100.0 / totalGraded;
+        CountDisplay = $"{count}  ({percent.ToString("0.#", CultureInfo.InvariantCulture)} %)";
+        BarWidth = maxCount <= 0 ? 0 : count * 200.0 / maxCount;
+    }
+}
+
+// ── Aufgabenanalyse-Zeile ──────────────────────────────────────────────────
+
+public class TaskAnalysisItem
+{
+    public string Label { get; }
+    public double AvgPercent { get; }
+    public string AvgPercentDisplay { get; }
+    public bool IsWeak { get; }
+    public double BarWidth { get; }
+
+    public TaskAnalysisItem(int nr, string? title, double avgPercent)
+    {
+        Label = string.IsNullOrWhiteSpace(title) ? $"Aufgabe {nr}" : $"{nr}. {title}";
+        AvgPercent = avgPercent;
+        AvgPercentDisplay = $"{avgPercent.ToString("0.#", CultureInfo.InvariantCulture)} %";
+        IsWeak = avgPercent < 50.0;
+        BarWidth = Math.Clamp(avgPercent, 0, 100) * 2.0;
+    }
+}

LehrerApp.Desktop/ViewModels/Groups/GroupViewModels.cs

@@ -177,6 +177,7 @@ public partial class GroupDetailViewModel : ObservableObject
     public Func<Exam, Task<bool>>? OnDuplicateExam { get; set; }
     public Func<ExamSummary, Task<bool>>? OnConfirmDeleteExam { get; set; }
     public Func<Exam, Task>? OnGradeExam { get; set; }
+    public Func<Exam, Task>? OnEvaluateExam { get; set; }
 
     public GroupDetailViewModel(IGroupRepository groups, IStudentRepository students,
         IEnrollmentRepository enrollments, IExamRepository exams, IGradeRepository grades,
@@ -286,6 +287,15 @@ public partial class GroupDetailViewModel : ObservableObject
         await OnGradeExam(exam);
     }
 
+    [RelayCommand(CanExecute = nameof(HasSelectedExam))]
+    private async Task EvaluateExam()
+    {
+        if (SelectedExam is null || OnEvaluateExam is null) return;
+        var exam = _exams.GetById(SelectedExam.Id);
+        if (exam is null) return;
+        await OnEvaluateExam(exam);
+    }
+
     [RelayCommand(CanExecute = nameof(HasSelectedExam))]
     private async Task DuplicateExam()
     {
@@ -341,6 +351,7 @@ public partial class GroupDetailViewModel : ObservableObject
     {
         EditExamCommand.NotifyCanExecuteChanged();
         GradeExamCommand.NotifyCanExecuteChanged();
+        EvaluateExamCommand.NotifyCanExecuteChanged();
         DuplicateExamCommand.NotifyCanExecuteChanged();
         DeleteExamCommand.NotifyCanExecuteChanged();
         AdvanceExamStatusCommand.NotifyCanExecuteChanged();

LehrerApp.Desktop/Views/Groups/ExamEvaluationDialog.axaml

@@ -0,0 +1,149 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="clr-namespace:LehrerApp.Desktop.ViewModels.Groups"
+        x:Class="LehrerApp.Desktop.Views.Groups.ExamEvaluationDialog"
+        x:DataType="vm:ExamEvaluationDialogViewModel"
+        Title="{Binding ExamTitle}"
+        Width="760" Height="820" MinWidth="600" MinHeight="480"
+        CanResize="True" WindowStartupLocation="CenterOwner">
+
+  <Grid RowDefinitions="*,Auto" Margin="24">
+    <ScrollViewer Grid.Row="0">
+      <StackPanel Spacing="16" Margin="0,0,12,0">
+
+        <StackPanel Spacing="2">
+          <TextBlock Text="{Binding ExamTitle}" FontSize="18" FontWeight="SemiBold"/>
+          <TextBlock Text="{Binding ExamDateLabel}" FontSize="12" Opacity="0.6"/>
+        </StackPanel>
+
+        <!-- Kennzahlen -->
+        <UniformGrid Columns="3" Rows="2">
+          <StackPanel Margin="0,0,12,10">
+            <TextBlock Text="DURCHSCHNITT" FontSize="10" FontWeight="Bold" Opacity="0.5"/>
+            <TextBlock Text="{Binding AverageDisplay}" FontSize="20" FontWeight="SemiBold"/>
+          </StackPanel>
+          <StackPanel Margin="0,0,12,10">
+            <TextBlock Text="MEDIAN" FontSize="10" FontWeight="Bold" Opacity="0.5"/>
+            <TextBlock Text="{Binding MedianDisplay}" FontSize="20" FontWeight="SemiBold"/>
+          </StackPanel>
+          <StackPanel Margin="0,0,12,10">
+            <TextBlock Text="BEWERTET / ABWESEND" FontSize="10" FontWeight="Bold" Opacity="0.5"/>
+            <TextBlock FontSize="20" FontWeight="SemiBold">
+              <Run Text="{Binding GradedCount}"/>
+              <Run Text=" / "/>
+              <Run Text="{Binding AbsentCount}"/>
+            </TextBlock>
+          </StackPanel>
+          <StackPanel Margin="0,0,12,0" IsVisible="{Binding BelowThresholdLabel1, Converter={x:Static StringConverters.IsNotNullOrEmpty}}">
+            <TextBlock Text="{Binding BelowThresholdLabel1}" FontSize="10" FontWeight="Bold" Opacity="0.5"
+                       TextWrapping="Wrap"/>
+            <TextBlock Text="{Binding BelowThresholdDisplay1}" FontSize="20" FontWeight="SemiBold"/>
+          </StackPanel>
+          <StackPanel Margin="0,0,12,0" IsVisible="{Binding BelowThresholdLabel2, Converter={x:Static StringConverters.IsNotNullOrEmpty}}">
+            <TextBlock Text="{Binding BelowThresholdLabel2}" FontSize="10" FontWeight="Bold" Opacity="0.5"
+                       TextWrapping="Wrap"/>
+            <TextBlock Text="{Binding BelowThresholdDisplay2}" FontSize="20" FontWeight="SemiBold"/>
+          </StackPanel>
+        </UniformGrid>
+
+        <Separator/>
+
+        <!-- Notenspiegel -->
+        <TextBlock Text="Notenspiegel" FontSize="14" FontWeight="SemiBold"/>
+        <ItemsControl ItemsSource="{Binding GradeDistribution}">
+          <ItemsControl.ItemTemplate>
+            <DataTemplate x:DataType="vm:GradeBarItem">
+              <Grid ColumnDefinitions="40,210,*" Margin="0,3">
+                <TextBlock Grid.Column="0" Text="{Binding Grade}" VerticalAlignment="Center" FontWeight="SemiBold"/>
+                <Border Grid.Column="1" HorizontalAlignment="Left" Height="16" CornerRadius="3"
+                        Width="{Binding BarWidth}"
+                        Background="{DynamicResource SystemControlBackgroundAccentBrush}"/>
+                <TextBlock Grid.Column="2" Text="{Binding CountDisplay}" FontSize="12" Opacity="0.7"
+                           VerticalAlignment="Center" Margin="8,0,0,0"/>
+              </Grid>
+            </DataTemplate>
+          </ItemsControl.ItemTemplate>
+        </ItemsControl>
+        <TextBlock Text="Noch keine bewerteten Ergebnisse." Opacity="0.4" FontSize="13"
+                   IsVisible="{Binding !GradedCount}"/>
+
+        <Separator/>
+
+        <!-- Aufgabenanalyse -->
+        <TextBlock Text="Aufgabenanalyse" FontSize="14" FontWeight="SemiBold"/>
+        <ItemsControl ItemsSource="{Binding TaskAnalysis}">
+          <ItemsControl.Styles>
+            <Style Selector="Border.taskbar">
+              <Setter Property="Background" Value="{DynamicResource SystemControlBackgroundAccentBrush}"/>
+            </Style>
+            <Style Selector="Border.taskbar.weak">
+              <Setter Property="Background" Value="#E53935"/>
+            </Style>
+            <Style Selector="TextBlock.tasklabel">
+              <Setter Property="Foreground" Value="{DynamicResource SystemControlForegroundBaseHighBrush}"/>
+            </Style>
+            <Style Selector="TextBlock.tasklabel.weak">
+              <Setter Property="Foreground" Value="#E53935"/>
+              <Setter Property="FontWeight" Value="SemiBold"/>
+            </Style>
+          </ItemsControl.Styles>
+          <ItemsControl.ItemTemplate>
+            <DataTemplate x:DataType="vm:TaskAnalysisItem">
+              <Grid ColumnDefinitions="180,210,*" Margin="0,3">
+                <TextBlock Grid.Column="0" Classes="tasklabel" Classes.weak="{Binding IsWeak}"
+                           Text="{Binding Label}" VerticalAlignment="Center" TextTrimming="CharacterEllipsis"/>
+                <Border Grid.Column="1" Classes="taskbar" Classes.weak="{Binding IsWeak}"
+                        HorizontalAlignment="Left" Height="16" CornerRadius="3" Width="{Binding BarWidth}"/>
+                <TextBlock Grid.Column="2" Text="{Binding AvgPercentDisplay}" FontSize="12" Opacity="0.7"
+                           VerticalAlignment="Center" Margin="8,0,0,0"/>
+              </Grid>
+            </DataTemplate>
+          </ItemsControl.ItemTemplate>
+        </ItemsControl>
+        <TextBlock Text="Auffällig schwache Aufgaben (Ø unter 50 %) sind rot markiert." Opacity="0.4" FontSize="11"
+                   IsVisible="{Binding TaskAnalysis.Count}"/>
+
+        <Separator/>
+
+        <!-- Notenschlüssel verschieben -->
+        <Grid ColumnDefinitions="*,Auto">
+          <TextBlock Grid.Column="0" Text="Notenschlüssel verschieben" FontSize="14" FontWeight="SemiBold" VerticalAlignment="Center"/>
+          <Button Grid.Column="1" Content="＋ Stufe" Command="{Binding AddGradingKeyRowCommand}"/>
+        </Grid>
+        <TextBlock Text="Änderungen wirken sich sofort auf den Notenspiegel oben aus. Erst mit &quot;Übernehmen&quot; werden sie an der Klausur gespeichert."
+                   FontSize="11" Opacity="0.5" TextWrapping="Wrap"/>
+
+        <ItemsControl ItemsSource="{Binding GradingKeyEntries}">
+          <ItemsControl.ItemTemplate>
+            <DataTemplate x:DataType="vm:GradingKeyEntryEditItem">
+              <Grid ColumnDefinitions="90,90,*,Auto" Margin="0,0,0,4">
+                <TextBox Grid.Column="0" Text="{Binding Grade}" PlaceholderText="Note" Margin="0,0,6,0"/>
+                <NumericUpDown Grid.Column="1" Value="{Binding MinPercent}" Minimum="0" Maximum="100"
+                               FormatString="0.##" Width="90" ShowButtonSpinner="False" Margin="0,0,6,0"/>
+                <TextBlock Grid.Column="2" Text="{Binding AbsolutePointsDisplay}" FontSize="12" Opacity="0.65"
+                           VerticalAlignment="Center"/>
+                <Button Grid.Column="3" Content="✕" Command="{Binding RemoveCommand}" Padding="6,2"/>
+              </Grid>
+            </DataTemplate>
+          </ItemsControl.ItemTemplate>
+        </ItemsControl>
+
+        <TextBlock Text="{Binding GradingKeyValidation}" Foreground="Red" FontSize="12"
+                   IsVisible="{Binding GradingKeyValidation, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+
+        <Grid ColumnDefinitions="*,Auto">
+          <TextBlock Grid.Column="0" Text="{Binding GradingKeyStatus}" Foreground="Green" FontSize="12"
+                     VerticalAlignment="Center"
+                     IsVisible="{Binding GradingKeyStatus, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+          <Button Grid.Column="1" Content="Übernehmen" Command="{Binding ApplyGradingKeyCommand}"/>
+        </Grid>
+
+      </StackPanel>
+    </ScrollViewer>
+
+    <Grid Grid.Row="1" ColumnDefinitions="Auto,*,Auto" Margin="0,16,0,0">
+      <Button Grid.Column="0" Content="Als CSV exportieren" Click="OnExportClick"/>
+      <Button Grid.Column="2" Content="Fertig" Click="OnClose"/>
+    </Grid>
+  </Grid>
+</Window>

LehrerApp.Desktop/Views/Groups/ExamEvaluationDialog.axaml.cs

@@ -0,0 +1,30 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using Avalonia.Platform.Storage;
+using LehrerApp.Desktop.ViewModels.Groups;
+
+namespace LehrerApp.Desktop.Views.Groups;
+
+public partial class ExamEvaluationDialog : Window
+{
+    public ExamEvaluationDialog() => InitializeComponent();
+
+    private async void OnExportClick(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is not ExamEvaluationDialogViewModel vm) return;
+        var topLevel = TopLevel.GetTopLevel(this);
+        if (topLevel is null) return;
+
+        var file = await topLevel.StorageProvider.SaveFilePickerAsync(new FilePickerSaveOptions
+        {
+            Title             = "Klausurauswertung exportieren",
+            SuggestedFileName = $"Auswertung_{vm.ExamTitle}.csv",
+            FileTypeChoices   = [new FilePickerFileType("CSV-Dateien") { Patterns = ["*.csv"] }],
+        });
+
+        if (file is null) return;
+        await File.WriteAllTextAsync(file.Path.LocalPath, vm.ExportCsv());
+    }
+
+    private void OnClose(object? sender, RoutedEventArgs e) => Close();
+}

LehrerApp.Desktop/Views/Groups/GroupDetailView.axaml

@@ -71,6 +71,7 @@
           <StackPanel Grid.Row="0" Orientation="Horizontal" Spacing="8" Margin="0,0,0,8"
                       IsVisible="{Binding SelectedExam, Converter={x:Static ObjectConverters.IsNotNull}}">
             <Button Content="Punkte eingeben" Command="{Binding GradeExamCommand}"/>
+            <Button Content="Auswertung"    Command="{Binding EvaluateExamCommand}"/>
             <Button Content="Bearbeiten"    Command="{Binding EditExamCommand}"/>
             <Button Content="Duplizieren"   Command="{Binding DuplicateExamCommand}"/>
             <SplitButton Content="Status ▸" Command="{Binding AdvanceExamStatusCommand}">
@@ -113,6 +114,7 @@
             <DataGrid.ContextMenu>
               <ContextMenu>
                 <MenuItem Header="Punkte eingeben" Command="{Binding GradeExamCommand}"/>
+                <MenuItem Header="Auswertung"    Command="{Binding EvaluateExamCommand}"/>
                 <MenuItem Header="Bearbeiten"    Command="{Binding EditExamCommand}"/>
                 <MenuItem Header="Duplizieren"   Command="{Binding DuplicateExamCommand}"/>
                 <MenuItem Header="Status">

LehrerApp.Desktop/Views/Groups/GroupDetailView.axaml.cs

@@ -22,6 +22,7 @@ public partial class GroupDetailView : UserControl
             vm.OnDuplicateExam   = ShowDuplicateExamDialog;
             vm.OnConfirmDeleteExam = ShowDeleteExamDialog;
             vm.OnGradeExam       = ShowGradeExamDialog;
+            vm.OnEvaluateExam    = ShowEvaluateExamDialog;
         }
     }
 
@@ -92,4 +93,19 @@ public partial class GroupDetailView : UserControl
         var owner = TopLevel.GetTopLevel(this) as Window;
         if (owner is not null) await dialog.ShowDialog(owner);
     }
+
+    private async Task ShowEvaluateExamDialog(Exam exam)
+    {
+        if (DataContext is not GroupDetailViewModel vm || vm.Group is null) return;
+
+        var dialogVm = new ExamEvaluationDialogViewModel(
+            App.Services.GetRequiredService<IExamRepository>(),
+            App.Services.GetRequiredService<IExamResultRepository>(),
+            App.Services.GetRequiredService<GradingService>(),
+            exam, vm.Group.GradingSystem);
+
+        var dialog = new ExamEvaluationDialog { DataContext = dialogVm };
+        var owner = TopLevel.GetTopLevel(this) as Window;
+        if (owner is not null) await dialog.ShowDialog(owner);
+    }
 }

TODO.md

@@ -75,12 +75,18 @@ Modelle `Exam`, `ExamTask`, `GradingKeyEntry`, `ExamResult` existieren bereits i
 - [x] **1.4.6** Autosave nach jeder Zelle (kein expliziter Speichern-Button nötig).
 
 ### 1.5 Klausurauswertung
-- [ ] **1.5.1** Notenspiegel (Häufigkeitsverteilung als Balken), Durchschnitt, Median,
+- [x] **1.5.1** Notenspiegel (Häufigkeitsverteilung als Balken), Durchschnitt, Median,
-      Anteil unter 4 / unter 5 Punkten.
+      Anteil unter 4 / unter 5 Punkten. Umgesetzt als neuer Dialog `ExamEvaluationDialog`,
-- [ ] **1.5.2** Aufgabenanalyse: durchschnittlicher Erfüllungsgrad pro Aufgabe in Prozent,
+      erreichbar über "Auswertung" im Klausuren-Tab. Bei Notensystem 1–6 zeigt der Schwellenwert
-      Kennzeichnung auffällig schwacher Aufgaben.
+      sinngemäß "Anteil nicht ausreichend (Note 5/6)" statt der Punktegrenzen. Abwesende werden
-- [ ] **1.5.3** Notenschlüssel nachträglich verschieben und Auswirkung sofort im Notenspiegel sehen.
+      aus allen Statistiken ausgeschlossen (löst damit auch den Hinweis aus 1.4.3 ein).
-- [ ] **1.5.4** Export der Auswertung (siehe 11.2).
+- [x] **1.5.2** Aufgabenanalyse: durchschnittlicher Erfüllungsgrad pro Aufgabe in Prozent,
+      Kennzeichnung auffällig schwacher Aufgaben (Ø < 50 %, rot markiert).
+- [x] **1.5.3** Notenschlüssel nachträglich verschieben und Auswirkung sofort im Notenspiegel sehen —
+      Änderungen wirken sich live aus, erst "Übernehmen" schreibt sie in die Klausur zurück.
+- [x] **1.5.4** Export der Auswertung — als eigenständiger CSV-Export direkt im Dialog umgesetzt
+      (analog zum bestehenden JSON-Export der Kompetenzkataloge), nicht über eine gemeinsame
+      Export-Infrastruktur, da Kapitel 11 ("Bisher nicht vorhanden — komplett neu") noch aussteht.
 
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