Stundenplan: Wochenraster, Wochennavigation, Ferien/Feiertage (Kapitel 4.3)

Neuer Stundenplan mit "Heute"-Standardansicht (Tagesliste unten angedockt,
gruppenübergreifendes Wochenraster mit Fach/Klasse/Raum/Thema, Vor-/Zurück-
Navigation zwischen Kalenderwochen) und separatem Bearbeiten-Raster für die
wöchentliche Zuordnung. Badges für Ferien-/Klausur-Nähe und ausgegraute
Ferientage direkt im Plan statt einer separaten Liste. Ferien-/Feiertage-
Pflege (Bundesland, Schulferien) sitzt jetzt in den Einstellungen statt im
Stundenplan selbst.

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

LehrerApp.Desktop/ViewModels/Settings/SettingsViewModel.cs

@@ -4,7 +4,9 @@ using LehrerApp.Core.Interfaces;
 using LehrerApp.Core.Models;
 using LehrerApp.Core.Services;
 using LehrerApp.Data;
+using LehrerApp.Desktop.ViewModels.Planning;
 using System.Collections.ObjectModel;
+using System.Globalization;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 
@@ -113,14 +115,30 @@ public partial class SettingsViewModel : ObservableObject
     /// Vom Code-Behind gesetzt: zeigt einen Bestätigungsdialog vor dem endgültigen Löschen.
     public Func<ExpiredDocumentItem, Task<bool>>? OnConfirmHardDelete { get; set; }
 
+    // ── Ferien & Feiertage (4.3.5, aus dem Stundenplan hierher verschoben) ───
+
+    [ObservableProperty] private string _selectedStateName = "";
+    [ObservableProperty] private string _newHolidayName = "";
+    [ObservableProperty] private string _newHolidayStartText = "";
+    [ObservableProperty] private string _newHolidayEndText = "";
+    [ObservableProperty] private string _holidayNameError = "";
+    [ObservableProperty] private string _holidayDateError = "";
+
+    public List<string> StateOptions { get; } = GermanStateDisplay.Options.ToList();
+    public ObservableCollection<SchoolHolidayItem> SchoolHolidayEntries { get; } = [];
+
     // ── Konstruktor ───────────────────────────────────────────────────────────
 
+    private readonly ISchoolHolidayRepository _schoolHolidays;
+    private readonly SchoolCalendarSettingsService _calendarSettings;
+
     public SettingsViewModel(ISubjectRepository subjects, ICompetencyDomainRepository domainRepo,
         IGradingKeyTemplateRepository gradingKeyTemplates, IGradingSchemeRepository gradingSchemes,
         GradingService grading, BackupService backups, DatabaseEncryptionService dbEncryption,
         AppLockService appLock, LiteDbContext dbContext, PrivacySettingsService privacy,
         IDocumentationRepository documentation, IStudentRepository students,
-        IShorthandCodeRepository shorthandCodes)
+        IShorthandCodeRepository shorthandCodes, ISchoolHolidayRepository schoolHolidays,
+        SchoolCalendarSettingsService calendarSettings)
     {
         _subjects   = subjects;
         _domainRepo = domainRepo;
@@ -135,6 +153,8 @@ public partial class SettingsViewModel : ObservableObject
         _documentation = documentation;
         _students     = students;
         _shorthandCodes = shorthandCodes;
+        _schoolHolidays = schoolHolidays;
+        _calendarSettings = calendarSettings;
         LoadSubjects();
         LoadShorthandCodes();
         LoadGradingKeyTemplates();
@@ -145,6 +165,51 @@ public partial class SettingsViewModel : ObservableObject
         AppLockTimeoutMinutes = _appLock.TimeoutMinutes;
         RetentionYears = _privacy.RetentionYears;
         LoadExpiredDocuments();
+        SelectedStateName = GermanStateDisplay.Label(_calendarSettings.State);
+        LoadSchoolHolidays();
+    }
+
+    // ── Ferien & Feiertage: Bundesland / Schulferien pflegen ─────────────────
+
+    partial void OnSelectedStateNameChanged(string value) =>
+        _calendarSettings.SetState(GermanStateDisplay.FromLabel(value));
+
+    private void LoadSchoolHolidays()
+    {
+        SchoolHolidayEntries.Clear();
+        foreach (var h in _schoolHolidays.GetAll().OrderBy(h => h.StartDate))
+            SchoolHolidayEntries.Add(new SchoolHolidayItem(h));
+    }
+
+    [RelayCommand]
+    private void AddSchoolHoliday()
+    {
+        HolidayNameError = ""; HolidayDateError = "";
+        var valid = true;
+
+        if (string.IsNullOrWhiteSpace(NewHolidayName)) { HolidayNameError = "Name erforderlich."; valid = false; }
+
+        var hasStart = DateOnly.TryParseExact(NewHolidayStartText, "dd.MM.yyyy", CultureInfo.InvariantCulture,
+            System.Globalization.DateTimeStyles.None, out var start);
+        var hasEnd = DateOnly.TryParseExact(NewHolidayEndText, "dd.MM.yyyy", CultureInfo.InvariantCulture,
+            System.Globalization.DateTimeStyles.None, out var end);
+
+        if (!hasStart || !hasEnd) { HolidayDateError = "Bitte Beginn und Ende im Format TT.MM.JJJJ angeben."; valid = false; }
+        else if (end < start) { HolidayDateError = "Das Ende darf nicht vor dem Beginn liegen."; valid = false; }
+
+        if (!valid) return;
+
+        _schoolHolidays.Save(new SchoolHoliday { Name = NewHolidayName.Trim(), StartDate = start, EndDate = end });
+        NewHolidayName = ""; NewHolidayStartText = ""; NewHolidayEndText = "";
+        LoadSchoolHolidays();
+    }
+
+    [RelayCommand]
+    private void RemoveSchoolHoliday(SchoolHolidayItem? item)
+    {
+        if (item is null) return;
+        _schoolHolidays.Delete(item.Id);
+        SchoolHolidayEntries.Remove(item);
     }
 
     // ── Datenschutz: Löschfristen ─────────────────────────────────────────────
@@ -770,6 +835,13 @@ public class ExpiredDocumentItem(Documentation d, string studentName)
     public string CreatedAtDisplay { get; } = d.CreatedAt.ToLocalTime().ToString("dd.MM.yyyy");
 }
 
+public class SchoolHolidayItem(SchoolHoliday h)
+{
+    public Guid   Id           { get; } = h.Id;
+    public string Name         { get; } = h.Name;
+    public string RangeDisplay { get; } = $"{h.StartDate:dd.MM.yyyy} – {h.EndDate:dd.MM.yyyy}";
+}
+
 // ── JSON DTOs ─────────────────────────────────────────────────────────────────
 
 internal class CatalogDto