LehrerApp/LehrerApp.Desktop/Views/ClassTeacher/ClassTeacherRegisterView.axaml

<UserControl xmlns="https://github.com/avaloniaui"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:vm="clr-namespace:LehrerApp.Desktop.ViewModels.ClassTeacher"
             x:Class="LehrerApp.Desktop.Views.ClassTeacher.ClassTeacherRegisterView"
             x:DataType="vm:ClassTeacherDetailsViewModel">

  <UserControl.Styles>
    <!-- Siehe Styles/SemanticBrushes.axaml: Farben per DynamicResource, damit der Theme-Wechsel
         sie live austauscht; die Statusfarbe je Zeile kommt als Style-Klasse aus dem ViewModel. -->
    <Style Selector="Border.filterCard">
      <Setter Property="Background" Value="{DynamicResource AppCardBackgroundBrush}"/>
      <Setter Property="BorderBrush" Value="{DynamicResource AppCardBorderBrush}"/>
      <Setter Property="BorderThickness" Value="1"/>
      <Setter Property="CornerRadius" Value="8"/>
      <Setter Property="Padding" Value="10"/>
    </Style>
    <Style Selector="TextBlock.status">
      <Setter Property="Foreground" Value="{DynamicResource AppStatusOkBrush}"/>
    </Style>
    <Style Selector="TextBlock.status.info">
      <Setter Property="Foreground" Value="{DynamicResource AppStatusInfoBrush}"/>
    </Style>
    <Style Selector="TextBlock.status.warning">
      <Setter Property="Foreground" Value="{DynamicResource AppStatusWarningBrush}"/>
    </Style>
    <Style Selector="TextBlock.status.danger">
      <Setter Property="Foreground" Value="{DynamicResource AppStatusDangerBrush}"/>
    </Style>
  </UserControl.Styles>

  <Grid RowDefinitions="Auto,Auto,Auto,*,Auto" Margin="16" RowSpacing="10">
    <Grid Grid.Row="0" ColumnDefinitions="*,Auto">
      <StackPanel>
        <TextBlock Text="Klassenbucheinträge" FontSize="22" FontWeight="SemiBold"/>
        <TextBlock Text="Einträge anderer Lehrkräfte – nur zur Ansicht" FontSize="12" Opacity="0.55"/>
      </StackPanel>
      <Button Grid.Column="1" Content="↻  Aus WebUntis aktualisieren" Command="{Binding RefreshCommand}"
              IsEnabled="{Binding !Busy}" Background="Transparent" Foreground="{DynamicResource AppAccentTextBrush}" VerticalAlignment="Center"/>
    </Grid>

    <Border Grid.Row="1" Classes="filterCard">
      <Grid RowDefinitions="Auto,Auto" RowSpacing="8">
        <Grid Grid.Row="0" ColumnDefinitions="155,Auto,*,Auto,*" ColumnSpacing="8">
          <ComboBox Grid.Column="0" SelectedIndex="{Binding QuickRangeIndex, Mode=TwoWay}">
            <ComboBoxItem Content="Heute"/><ComboBoxItem Content="Letzte 7 Tage"/><ComboBoxItem Content="Letzte 30 Tage"/>
          </ComboBox>
          <TextBlock Grid.Column="1" Text="von" VerticalAlignment="Center" Opacity="0.6"/>
          <CalendarDatePicker Grid.Column="2" SelectedDate="{Binding StartDate}" HorizontalAlignment="Stretch"/>
          <TextBlock Grid.Column="3" Text="bis" VerticalAlignment="Center" Opacity="0.6"/>
          <CalendarDatePicker Grid.Column="4" SelectedDate="{Binding EndDate}" HorizontalAlignment="Stretch"/>
        </Grid>
        <Grid Grid.Row="1" ColumnDefinitions="*,Auto,Auto" ColumnSpacing="8">
          <TextBox Grid.Column="0" Text="{Binding StudentFilter, Mode=TwoWay}" PlaceholderText="Schüler*in filtern…"/>
          <Button Grid.Column="1" Content="Anzeigen" Command="{Binding ApplyFilterCommand}" IsEnabled="{Binding !Busy}"/>
          <Button Grid.Column="2" Content="Filter löschen" Command="{Binding ClearStudentFilterCommand}"
                  IsVisible="{Binding StudentFilter, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
        </Grid>
      </Grid>
    </Border>

    <!-- Nutzer-Feedback: die reine Gesamtzahl der Einträge sagt wenig, eine Aufschlüsselung nach
         Kategorie ("Hausaufgaben fehlen: 12× — 5× Ben Schmidt, 3× Ada Müller") ist die eigentlich
         interessante Information. Als Chip-Reihe statt eigener Spalte in der Tabelle, damit die
         bestehenden Spalten unangetastet bleiben. -->
    <Border Grid.Row="2" Classes="filterCard" IsVisible="{Binding HasCategoryAggregates}">
      <StackPanel Spacing="6">
        <TextBlock Text="Kategorien im Zeitraum" FontSize="12" FontWeight="SemiBold" Opacity="0.7"/>
        <ItemsControl ItemsSource="{Binding CategoryAggregates}">
          <ItemsControl.ItemsPanel>
            <ItemsPanelTemplate>
              <WrapPanel/>
            </ItemsPanelTemplate>
          </ItemsControl.ItemsPanel>
          <ItemsControl.ItemTemplate>
            <DataTemplate x:DataType="vm:ClassTeacherCategoryAggregateRow">
              <Border Background="{DynamicResource AppChipBackgroundBrush}" CornerRadius="5"
                      Padding="8,4" Margin="0,0,6,6">
                <StackPanel Orientation="Horizontal" Spacing="4">
                  <TextBlock Text="{Binding CategoryName}" FontSize="11" FontWeight="SemiBold"/>
                  <TextBlock Text="{Binding SummaryLabel}" FontSize="11" Opacity="0.6"/>
                </StackPanel>
              </Border>
            </DataTemplate>
          </ItemsControl.ItemTemplate>
        </ItemsControl>
      </StackPanel>
    </Border>

    <Grid Grid.Row="3">
      <DataGrid ItemsSource="{Binding Entries}" AutoGenerateColumns="False" IsReadOnly="True"
                GridLinesVisibility="Horizontal" BorderBrush="{DynamicResource AppCardBorderBrush}" BorderThickness="1"
                CanUserResizeColumns="True" CanUserSortColumns="True" RowHeight="46">
        <DataGrid.Columns>
          <DataGridTextColumn Header="Datum" Binding="{Binding DateLabel}" Width="105"/>
          <DataGridTextColumn Header="Schüler*in" Binding="{Binding StudentDisplayName}" Width="1.25*"/>
          <DataGridTextColumn Header="Fach" Binding="{Binding Subject}" Width="0.7*"/>
          <DataGridTextColumn Header="Lehrkraft" Binding="{Binding TeacherUsername}" Width="0.8*"/>
          <DataGridTextColumn Header="Kategorie" Binding="{Binding CategoryName}" Width="1*"/>
          <DataGridTextColumn Header="Gruppe" Binding="{Binding CategoryGroup}" Width="0.8*"/>
          <DataGridTextColumn Header="Eintrag" Binding="{Binding Text}" Width="2*"/>
        </DataGrid.Columns>
      </DataGrid>
      <StackPanel IsVisible="{Binding !HasEntries}" HorizontalAlignment="Center" VerticalAlignment="Center" Spacing="5">
        <TextBlock Text="Keine Klassenbucheinträge im gewählten Zeitraum" FontWeight="SemiBold"/>
        <TextBlock Text="Passe Zeitraum oder Schülerfilter an." FontSize="12" Opacity="0.55"/>
      </StackPanel>
    </Grid>
    <TextBlock Grid.Row="4" Text="{Binding Status}" FontSize="11" Opacity="0.6"/>
  </Grid>
</UserControl>