Add animated classroom grouping with saved editable plans

Directory.Packages.props

@@ -9,6 +9,7 @@
     <PackageVersion Include="Avalonia.Themes.Fluent" Version="12.0.4" />
     <PackageVersion Include="Avalonia.Fonts.Inter"        Version="12.0.4" />
     <PackageVersion Include="Avalonia.Controls.DataGrid"  Version="12.0.0" />
+    <PackageVersion Include="Avalonia.Labs.Lottie" Version="12.0.2" />
 
     <!-- MVVM & DI – .NET 10 kompatibel -->
     <PackageVersion Include="CommunityToolkit.Mvvm"                    Version="8.4.0" />

LehrerApp.Core/Interfaces/IRepositories.cs

@@ -29,6 +29,14 @@ public interface ISeatingPlanRepository
     /// wieder her (14.3). Tut nichts, falls der Papierkorb-Eintrag nicht (mehr) existiert.</summary>
     void Restore(Guid trashId);
 }
+public interface IStudentGroupPlanRepository
+{
+    StudentGroupPlan? GetById(Guid id);
+    List<StudentGroupPlan> GetByGroup(Guid groupId);
+    List<StudentGroupPlan> GetByStudent(Guid studentId);
+    void Save(StudentGroupPlan plan);
+    void Delete(Guid id);
+}
 public interface IGroupMembershipRepository
 {
     List<GroupMembership> GetByStudent(Guid studentId);

LehrerApp.Core/Models/Student.cs

@@ -52,9 +52,10 @@ public sealed record StudentReferenceSummary(
     int Grades,
     int ReportGrades,
     int ParticipationEntries,
-    int DocumentationEntries)
+    int DocumentationEntries,
+    int StudentGroupPlans = 0)
 {
     public int Total => Memberships + ExamResults + Grades + ReportGrades
-                        + ParticipationEntries + DocumentationEntries;
+                        + ParticipationEntries + DocumentationEntries + StudentGroupPlans;
     public bool HasReferences => Total > 0;
 }

LehrerApp.Core/Models/StudentGroupPlan.cs

@@ -0,0 +1,17 @@
+namespace LehrerApp.Core.Models;
+
+/// <summary>Eine wiederverwendbare Einteilung innerhalb einer Lerngruppe.</summary>
+public class StudentGroupPlan
+{
+    public Guid Id { get; set; } = Guid.NewGuid();
+    public Guid GroupId { get; set; }
+    public string Name { get; set; } = "";
+    public List<StudentGroupPlanGroup> Groups { get; set; } = [];
+    public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+    public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
+}
+
+public class StudentGroupPlanGroup
+{
+    public List<Guid> StudentIds { get; set; } = [];
+}

LehrerApp.Core/Services/PersonalDataExportService.cs

@@ -22,7 +22,8 @@ public class PersonalDataExportService(
     IExamResultRepository examResults,
     IParticipationRepository participation,
     IDocumentationRepository documentation,
-    ISeatingPlanRepository seatingPlans)
+    ISeatingPlanRepository seatingPlans,
+    IStudentGroupPlanRepository? studentGroupPlans = null)
 {
     public string ExportAsJson(Guid studentId)
     {
@@ -56,6 +57,16 @@ public class PersonalDataExportService(
                         Platz = a.Column + 1,
                     }))
                 .ToList(),
+            GespeicherteGruppeneinteilungen = (studentGroupPlans?.GetByStudent(studentId) ?? [])
+                .SelectMany(plan => plan.Groups.Select((subgroup, index) => new
+                {
+                    Einteilung = plan.Name,
+                    Gruppe = index + 1,
+                    Enthalten = subgroup.StudentIds.Contains(studentId),
+                }))
+                .Where(entry => entry.Enthalten)
+                .Select(entry => new { entry.Einteilung, entry.Gruppe })
+                .ToList(),
         };
 
         return JsonSerializer.Serialize(dto, new JsonSerializerOptions

LehrerApp.Data.Tests/RepositoryTests.cs

@@ -8,6 +8,72 @@ public sealed class RepositoryTests
 {
     private static LiteDbContext NewInMemoryContext() => new(new MemoryStream());
 
+    [Fact]
+    public void StudentGroupPlanRepository_SpeichertEinteilungUndLoeschtSieMitDerLerngruppe()
+    {
+        using var db = NewInMemoryContext();
+        var group = new LearningGroup { Name = "8a" };
+        new GroupRepository(db).Save(group);
+        var studentIds = new[] { Guid.NewGuid(), Guid.NewGuid(), Guid.NewGuid() };
+        var plan = new StudentGroupPlan
+        {
+            GroupId = group.Id,
+            Name = "  Projektwoche  ",
+            Groups =
+            [
+                new StudentGroupPlanGroup { StudentIds = [studentIds[0], studentIds[1]] },
+                new StudentGroupPlanGroup { StudentIds = [studentIds[2]] },
+            ],
+        };
+        var changes = new List<(string Type, string Operation)>();
+        db.OnChange = (type, _, operation, _) => changes.Add((type, operation));
+        var repo = new StudentGroupPlanRepository(db);
+
+        repo.Save(plan);
+        Assert.Equal("Projektwoche", repo.GetById(plan.Id)?.Name);
+        Assert.Equal(studentIds[2], repo.GetByGroup(group.Id).Single().Groups[1].StudentIds.Single());
+        Assert.Equal(plan.Id, Assert.Single(repo.GetByStudent(studentIds[0])).Id);
+        Assert.Contains((nameof(StudentGroupPlan), "Save"), changes);
+
+        var student = new Student { Id = studentIds[0], FirstName = "Anna", LastName = "Beispiel" };
+        var students = new StudentRepository(db);
+        students.Save(student);
+        Assert.Throws<InvalidOperationException>(() => students.Delete(student.Id));
+
+        new GroupRepository(db).Delete(group.Id);
+        Assert.Empty(repo.GetByGroup(group.Id));
+    }
+
+    [Fact]
+    public void StudentGroupPlanRepository_VerhindertDoppelteSchuelerUndNamen()
+    {
+        using var db = NewInMemoryContext();
+        var group = new LearningGroup { Name = "8a" };
+        new GroupRepository(db).Save(group);
+        var repo = new StudentGroupPlanRepository(db);
+        var studentId = Guid.NewGuid();
+        Assert.Throws<InvalidOperationException>(() => repo.Save(new StudentGroupPlan
+        {
+            GroupId = group.Id, Name = "Doppelt",
+            Groups =
+            [
+                new StudentGroupPlanGroup { StudentIds = [studentId] },
+                new StudentGroupPlanGroup { StudentIds = [studentId] },
+            ],
+        }));
+
+        repo.Save(new StudentGroupPlan
+        {
+            GroupId = group.Id, Name = "Projektwoche",
+            Groups = [new StudentGroupPlanGroup { StudentIds = [studentId] }],
+        });
+        Assert.Throws<InvalidOperationException>(() => repo.Save(new StudentGroupPlan
+        {
+            GroupId = group.Id, Name = "projektwoche",
+            Groups = [new StudentGroupPlanGroup()],
+        }));
+    }
+
     // ── StudentRepository ─────────────────────────────────────────────────────
 
     [Fact]

LehrerApp.Data/LiteDbContext.cs

@@ -41,6 +41,7 @@ public class LiteDbContext : IDisposable
     public ILiteCollection<Student>       Students      => _db.GetCollection<Student>("students");
     public ILiteCollection<LearningGroup> Groups        => _db.GetCollection<LearningGroup>("groups");
     public ILiteCollection<SeatingPlan>   SeatingPlans  => _db.GetCollection<SeatingPlan>("seating_plans");
+    public ILiteCollection<StudentGroupPlan> StudentGroupPlans => _db.GetCollection<StudentGroupPlan>("student_group_plans");
     public ILiteCollection<GroupMembership> Memberships => _db.GetCollection<GroupMembership>("group_memberships");
     public ILiteCollection<Exam>          Exams         => _db.GetCollection<Exam>("exams");
     public ILiteCollection<ExamResult>    ExamResults   => _db.GetCollection<ExamResult>("exam_results");
@@ -141,6 +142,8 @@ public class LiteDbContext : IDisposable
 
             foreach (var plan in SeatingPlans.Find(p => p.GroupId == id).ToList())
                 SeatingPlans.Delete(plan.Id);
+            foreach (var plan in StudentGroupPlans.Find(p => p.GroupId == id).ToList())
+                StudentGroupPlans.Delete(plan.Id);
 
             // Dokumentation und Arbeitszeit sind historische Nachweise. Sie bleiben erhalten,
             // werden aber von der nicht mehr existierenden Lerngruppe entkoppelt.
@@ -659,6 +662,7 @@ public class LiteDbContext : IDisposable
         Groups.EnsureIndex(x => x.SchoolYear);
         Groups.EnsureIndex(x => x.IsActive);
         SeatingPlans.EnsureIndex(x => x.GroupId);
+        StudentGroupPlans.EnsureIndex(x => x.GroupId);
         Memberships.EnsureIndex(x => x.StudentId);
         Memberships.EnsureIndex(x => x.GroupId);
         Memberships.EnsureIndex("ux_student_group",

LehrerApp.Data/Repositories/AllRepositories.cs

@@ -34,7 +34,9 @@ public class StudentRepository(LiteDbContext db) : IStudentRepository
         db.Grades.Count(g => g.StudentId == studentId),
         db.ReportGrades.Count(g => g.StudentId == studentId),
         db.ParticipationEntries.Count(e => e.StudentId == studentId),
-        db.Documentation.FindAll().Count(d => d.Concerns(studentId)));
+        db.Documentation.FindAll().Count(d => d.Concerns(studentId)),
+        db.StudentGroupPlans.FindAll().Count(plan =>
+            plan.Groups.Any(group => group.StudentIds.Contains(studentId))));
     public void Save(Student s)
     {
         s.ExternalIds ??= [];

LehrerApp.Data/Repositories/StudentGroupPlanRepository.cs

@@ -0,0 +1,55 @@
+using LehrerApp.Core.Interfaces;
+using LehrerApp.Core.Models;
+
+namespace LehrerApp.Data.Repositories;
+
+public class StudentGroupPlanRepository(LiteDbContext db) : IStudentGroupPlanRepository
+{
+    public StudentGroupPlan? GetById(Guid id) => db.StudentGroupPlans.FindById(id);
+
+    public List<StudentGroupPlan> GetByGroup(Guid groupId) =>
+        db.StudentGroupPlans.Find(p => p.GroupId == groupId)
+            .OrderByDescending(p => p.UpdatedAt).ToList();
+
+    public List<StudentGroupPlan> GetByStudent(Guid studentId) =>
+        db.StudentGroupPlans.FindAll()
+            .Where(plan => plan.Groups.Any(group => group.StudentIds.Contains(studentId)))
+            .OrderByDescending(plan => plan.UpdatedAt).ToList();
+
+    public void Save(StudentGroupPlan plan)
+    {
+        if (db.Groups.FindById(plan.GroupId) is null)
+            throw new InvalidOperationException("Die zugehörige Lerngruppe existiert nicht.");
+        ArchivedGroupWriteGuard.EnsureActive(db, plan.GroupId);
+        plan.Name = plan.Name?.Trim() ?? "";
+        if (plan.Name.Length == 0)
+            throw new ArgumentException("Bitte einen Namen für die Gruppeneinteilung eingeben.");
+        plan.Groups ??= [];
+        if (plan.Groups.Count == 0)
+            throw new InvalidOperationException("Die Gruppeneinteilung enthält keine Gruppen.");
+        var ids = plan.Groups.SelectMany(g => g.StudentIds ?? []).ToList();
+        if (ids.Count != ids.Distinct().Count())
+            throw new InvalidOperationException("Ein Schüler darf nur in einer Gruppe stehen.");
+        if (db.StudentGroupPlans.Find(p => p.GroupId == plan.GroupId)
+            .Any(p => p.Id != plan.Id && string.Equals(p.Name, plan.Name, StringComparison.OrdinalIgnoreCase)))
+            throw new InvalidOperationException("Eine gespeicherte Einteilung mit diesem Namen gibt es bereits.");
+
+        if (db.StudentGroupPlans.FindById(plan.Id) is { } existing)
+        {
+            if (existing.GroupId != plan.GroupId)
+                throw new InvalidOperationException("Eine Gruppeneinteilung kann nicht in eine andere Lerngruppe verschoben werden.");
+            plan.CreatedAt = existing.CreatedAt;
+        }
+        plan.UpdatedAt = DateTime.UtcNow;
+        db.StudentGroupPlans.Upsert(plan);
+        db.OnChange?.Invoke(nameof(StudentGroupPlan), plan.Id.ToString(), "Save", plan);
+    }
+
+    public void Delete(Guid id)
+    {
+        if (db.StudentGroupPlans.FindById(id) is not { } plan) return;
+        ArchivedGroupWriteGuard.EnsureActive(db, plan.GroupId);
+        db.StudentGroupPlans.Delete(id);
+        db.OnChange?.Invoke(nameof(StudentGroupPlan), id.ToString(), "Delete", null);
+    }
+}

LehrerApp.Desktop.Tests/Fakes.cs

@@ -179,6 +179,22 @@ public class FakeSeatingPlans(List<SeatingPlan>? initial = null) : ISeatingPlanR
     public void Restore(Guid trashId) { }
 }
 
+public class FakeStudentGroupPlans : IStudentGroupPlanRepository
+{
+    private readonly List<StudentGroupPlan> _plans = [];
+    public StudentGroupPlan? GetById(Guid id) => _plans.FirstOrDefault(p => p.Id == id);
+    public List<StudentGroupPlan> GetByGroup(Guid groupId) =>
+        _plans.Where(p => p.GroupId == groupId).ToList();
+    public List<StudentGroupPlan> GetByStudent(Guid studentId) =>
+        _plans.Where(p => p.Groups.Any(g => g.StudentIds.Contains(studentId))).ToList();
+    public void Save(StudentGroupPlan plan)
+    {
+        _plans.RemoveAll(p => p.Id == plan.Id);
+        _plans.Add(plan);
+    }
+    public void Delete(Guid id) => _plans.RemoveAll(p => p.Id == id);
+}
+
 public class FakeTrash(List<TrashedItem>? initial = null) : ITrashRepository
 {
     private readonly List<TrashedItem> _all = initial ?? [];

LehrerApp.Desktop.Tests/PersonalDataExportServiceTests.cs

@@ -31,8 +31,14 @@ public sealed class PersonalDataExportServiceTests
                 Assignments = [new SeatAssignment { Row = 1, Column = 2, StudentId = studentId }],
             },
         ]);
+        var groupPlans = new FakeStudentGroupPlans();
+        groupPlans.Save(new StudentGroupPlan
+        {
+            GroupId = groupId, Name = "Projektwoche",
+            Groups = [new StudentGroupPlanGroup { StudentIds = [studentId] }],
+        });
         var service = new PersonalDataExportService(students, groups, memberships, grades, results, entries,
-            documentation, seatingPlans);
+            documentation, seatingPlans, groupPlans);
 
         var json = service.ExportAsJson(studentId);
 
@@ -41,6 +47,7 @@ public sealed class PersonalDataExportServiceTests
         Assert.Contains("\"Value\": \"2\"", json);
         Assert.Contains("\"Sitzplan\": \"Standard\"", json);
         Assert.Contains("\"Reihe\": 2", json);
+        Assert.Contains("Projektwoche", json);
     }
 
     [Fact]
@@ -53,4 +60,23 @@ public sealed class PersonalDataExportServiceTests
 
         Assert.Throws<InvalidOperationException>(() => service.ExportAsJson(Guid.NewGuid()));
     }
+
+    [Fact]
+    public void ExportAsJson_EnthaeltGespeichertenPlanAuchNachEndeDerMitgliedschaft()
+    {
+        var student = new Student { FirstName = "Anna", LastName = "Beispiel" };
+        var groupId = Guid.NewGuid();
+        var plans = new FakeStudentGroupPlans();
+        plans.Save(new StudentGroupPlan
+        {
+            GroupId = groupId, Name = "Alte Projektgruppe",
+            Groups = [new StudentGroupPlanGroup { StudentIds = [student.Id] }],
+        });
+        var service = new PersonalDataExportService(
+            new FakeStudents([student]), new FakeGroups([]), new FakeMemberships([]),
+            new FakeGrades(), new FakeResults(), new FakeEntries(), new FakeDocumentation(),
+            new FakeSeatingPlans(), plans);
+
+        Assert.Contains("Alte Projektgruppe", service.ExportAsJson(student.Id));
+    }
 }

LehrerApp.Desktop.Tests/StudentGroupGeneratorViewModelTests.cs

@@ -7,7 +7,8 @@ namespace LehrerApp.Desktop.Tests;
 public sealed class StudentGroupGeneratorViewModelTests
 {
     private static (StudentGroupGeneratorViewModel Vm, List<Student> Students, LearningGroup Group,
-        FakeSessions Sessions, FakeEntries Entries) Build(int studentCount = 10)
+        FakeSessions Sessions, FakeEntries Entries) Build(int studentCount = 10,
+            FakeStudentGroupPlans? savedPlans = null)
     {
         var group = new LearningGroup { Name = "8a", GradingSystem = GradingSystem.Grades1To6 };
         var students = Enumerable.Range(1, studentCount).Select(i => new Student
@@ -22,10 +23,77 @@ public sealed class StudentGroupGeneratorViewModelTests
         var entries = new FakeEntries();
         var vm = new StudentGroupGeneratorViewModel(
             new FakeStudents(students), new FakeGroups([group]), new FakeMemberships(memberships),
-            sessions, entries, new FakeGrades(), group.Id, new Random(7));
+            sessions, entries, new FakeGrades(), group.Id, new Random(7), savedPlans);
         return (vm, students, group, sessions, entries);
     }
 
+    [Fact]
+    public void ManuelleUmverteilung_WirdGespeichertUndSpaeterWiederGeladen()
+    {
+        var plans = new FakeStudentGroupPlans();
+        var (vm, students, group, _, _) = Build(6, plans);
+        vm.TargetGroupCount = 2;
+        vm.CountPriority = 100;
+        vm.GenerateCommand.Execute(null);
+        var source = vm.GeneratedGroups[0];
+        var target = vm.GeneratedGroups[1];
+        var member = source.Members[0];
+
+        Assert.True(vm.MoveStudent(member, target));
+        Assert.False(vm.MoveStudent(member, target));
+        Assert.DoesNotContain(member, source.Members);
+        vm.PlanName = "Projektwoche";
+        vm.SavePlanCommand.Execute(null);
+
+        var saved = Assert.Single(plans.GetByGroup(group.Id));
+        Assert.Equal("Projektwoche", saved.Name);
+        Assert.Contains(member.Id, saved.Groups[1].StudentIds);
+        Assert.False(vm.HasUnsavedChanges);
+
+        vm.GenerateCommand.Execute(null);
+        vm.SelectedSavedPlan = Assert.Single(vm.SavedPlans);
+        vm.LoadSavedPlanCommand.Execute(null);
+        Assert.Contains(vm.GeneratedGroups[1].Members, m => m.Id == member.Id);
+        Assert.DoesNotContain(vm.GeneratedGroups[0].Members, m => m.Id == member.Id);
+        Assert.False(vm.HasUnsavedChanges);
+        Assert.Equal("Projektwoche", vm.PlanName);
+
+        var reopened = new StudentGroupGeneratorViewModel(
+            new FakeStudents(students), new FakeGroups([group]),
+            new FakeMemberships(students.Select(s => new GroupMembership
+            {
+                GroupId = group.Id, StudentId = s.Id,
+            }).ToList()),
+            new FakeSessions([]), new FakeEntries(), new FakeGrades(), group.Id,
+            savedPlans: plans);
+        reopened.SelectedSavedPlan = Assert.Single(reopened.SavedPlans);
+        reopened.LoadSavedPlanCommand.Execute(null);
+        Assert.Contains(reopened.GeneratedGroups[1].Members, m => m.Id == member.Id);
+
+        reopened.PlanName = "Projektwoche aktualisiert";
+        reopened.SavePlanCommand.Execute(null);
+        Assert.Equal("Projektwoche aktualisiert", Assert.Single(plans.GetByGroup(group.Id)).Name);
+    }
+
+    [Fact]
+    public void SpeichernUeberschreibtAusgewaehltenPlanErstNachDemLaden()
+    {
+        var plans = new FakeStudentGroupPlans();
+        var (vm, _, group, _, _) = Build(6, plans);
+        vm.GenerateCommand.Execute(null);
+        vm.PlanName = "Alter Plan";
+        vm.SavePlanCommand.Execute(null);
+
+        vm.GenerateCommand.Execute(null);
+        vm.SelectedSavedPlan = Assert.Single(vm.SavedPlans);
+        vm.PlanName = "Neuer Plan";
+        vm.SavePlanCommand.Execute(null);
+
+        Assert.Equal(2, plans.GetByGroup(group.Id).Count);
+        Assert.Contains(plans.GetByGroup(group.Id), p => p.Name == "Alter Plan");
+        Assert.Contains(plans.GetByGroup(group.Id), p => p.Name == "Neuer Plan");
+    }
+
     [Fact]
     public void FesteZielgroesse_ErzeugtPassendeAnzahlMitKleinerAusnahme()
     {

LehrerApp.Desktop/AppBootstrapper.cs

@@ -156,6 +156,7 @@ public static class AppBootstrapper
         services.AddSingleton<IStudentRepository,       StudentRepository>();
         services.AddSingleton<IGroupRepository,         GroupRepository>();
         services.AddSingleton<ISeatingPlanRepository,   SeatingPlanRepository>();
+        services.AddSingleton<IStudentGroupPlanRepository, StudentGroupPlanRepository>();
         services.AddSingleton<ITrashRepository,         TrashRepository>();
         services.AddSingleton<IGroupMembershipRepository, GroupMembershipRepository>();
         services.AddSingleton<IExamRepository,          ExamRepository>();

LehrerApp.Desktop/Assets/Animations/LotterySpinWheel.json

@@ -0,0 +1 @@
+{"v":"5.7.8","fr":25,"ip":0,"op":25,"w":1080,"h":1080,"nm":"[ pecah Asset - Games Roda Keberuntungan ] EMOS - Juni","ddd":0,"assets":[],"layers":[{"ddd":0,"ind":1,"ty":4,"nm":"link-tengah Outlines","sr":1,"ks":{"o":{"a":0,"k":100,"ix":11},"r":{"a":0,"k":0,"ix":10},"p":{"a":0,"k":[538.46,407.962,0],"ix":2,"l":2},"a":{"a":0,"k":[65.18,65.182,0],"ix":1,"l":2},"s":{"a":0,"k":[100,100,100],"ix":6,"l":2}},"ao":0,"shapes":[{"ty":"gr","it":[{"ind":0,"ty":"sh","ix":1,"ks":{"a":0,"k":{"i":[[-1.586,31.425],[-31.425,-1.586],[1.586,-31.426],[31.425,1.588]],"o":[[1.588,-31.423],[31.426,1.588],[-1.589,31.425],[-31.425,-1.586]],"v":[[-56.9,-2.875],[2.873,-56.901],[56.9,2.873],[-2.874,56.899]],"c":true},"ix":2},"nm":"Path 1","mn":"ADBE Vector Shape - Group","hd":false},{"ind":1,"ty":"sh","ix":2,"ks":{"a":0,"k":{"i":[[-1.668,33.037],[33.036,1.668],[1.668,-33.037],[-33.036,-1.671]],"o":[[1.67,-33.037],[-33.037,-1.668],[-1.67,33.036],[33.037,1.668]],"v":[[59.817,3.02],[3.021,-59.818],[-59.817,-3.022],[-3.022,59.818]],"c":true},"ix":2},"nm":"Path 2","mn":"ADBE Vector Shape - 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Group","hd":false},{"ty":"mm","mm":1,"nm":"Merge Paths 1","mn":"ADBE Vector Filter - Merge","hd":false},{"ty":"fl","c":{"a":0,"k":[1,1,1,1],"ix":4},"o":{"a":0,"k":100,"ix":5},"r":1,"bm":0,"nm":"Fill 1","mn":"ADBE Vector Graphic - Fill","hd":false},{"ty":"tr","p":{"a":0,"k":[65.181,65.182],"ix":2},"a":{"a":0,"k":[0,0],"ix":1},"s":{"a":0,"k":[100,100],"ix":3},"r":{"a":0,"k":0,"ix":6},"o":{"a":0,"k":100,"ix":7},"sk":{"a":0,"k":0,"ix":4},"sa":{"a":0,"k":0,"ix":5},"nm":"Transform"}],"nm":"Group 2","np":6,"cix":2,"bm":0,"ix":2,"mn":"ADBE Vector Group","hd":false},{"ty":"gr","it":[{"ind":0,"ty":"sh","ix":1,"ks":{"a":0,"k":{"i":[[-1.55,30.701],[30.701,1.55],[1.55,-30.701],[-30.702,-1.552]],"o":[[1.552,-30.701],[-30.701,-1.55],[-1.552,30.701],[30.701,1.55]],"v":[[55.589,2.806],[2.808,-55.59],[-55.588,-2.809],[-2.808,55.59]],"c":true},"ix":2},"nm":"Path 1","mn":"ADBE Vector Shape - Group","hd":false},{"ty":"fl","c":{"a":0,"k":[0.3686274509803922,0.4470588235294118,0.8941176470588236,1],"ix":4},"o":{"a":0,"k":100,"ix":5},"r":1,"bm":0,"nm":"Fill 1","mn":"ADBE Vector Graphic - 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Group","hd":false},{"ty":"fl","c":{"a":0,"k":[0.2196078431372549,0.28627450980392155,0.8196078431372549,1],"ix":4},"o":{"a":0,"k":100,"ix":5},"r":1,"bm":0,"nm":"Fill 1","mn":"ADBE Vector Graphic - Fill","hd":false},{"ty":"tr","p":{"a":0,"k":[112.538,63.94],"ix":2},"a":{"a":0,"k":[0,0],"ix":1},"s":{"a":0,"k":[100,100],"ix":3},"r":{"a":0,"k":0,"ix":6},"o":{"a":0,"k":100,"ix":7},"sk":{"a":0,"k"Line truncated

LehrerApp.Desktop/Assets/Animations/Teamwork.json

@@ -0,0 +1 @@
+{"v":"5.6.6","fr":60,"ip":60,"op":120,"w":600,"h":600,"nm":"development and submittals","ddd":0,"assets":[],"layers":[{"ddd":0,"ind":1,"ty":4,"nm":"person-top-face-outlinne Outlines","parent":8,"sr":1,"ks":{"o":{"a":0,"k":100,"ix":11},"r":{"a":0,"k":0,"ix":10},"p":{"a":0,"k":[73.415,-16.001,0],"ix":2},"a":{"a":0,"k":[33.313,42.52,0],"ix":1},"s":{"a":0,"k":[100,100,100],"ix":6}},"ao":0,"shapes":[{"ty":"gr","it":[{"ind":0,"ty":"sh","ix":1,"ks":{"a":0,"k":{"i":[[4.515,0],[2.745,1.593],[0,10.18],[-5.843,10.003],[-8.233,4.781],[-6.463,-3.719],[0,-10.181],[5.754,-10.093],[8.234,-4.692]],"o":[[-3.276,0],[-6.551,-3.718],[0,-9.561],[5.754,-10.004],[8.853,-5.046],[6.551,3.718],[0,9.561],[-5.843,10.092],[-5.223,2.921]],"v":[[-13.102,41.52],[-22.221,39.13],[-32.313,17.529],[-23.283,-12.836],[-1.505,-35.765],[22.22,-37.801],[32.313,-16.2],[23.372,14.165],[1.593,37.094]],"c":true},"ix":2},"nm":"Path 1","mn":"ADBE Vector Shape - Group","hd":false},{"ind":1,"ty":"sh","ix":2,"ks":{"a":0,"k":{"i":[[2.214,0],[4.161,-2.301],[5.312,-9.118],[0,-8.41],[-4.516,-2.656],[-6.816,3.895],[-0.089,0],[-5.222,9.119],[0,8.498],[4.603,2.656]],"o":[[-3.452,0],[-7.348,4.25],[-5.312,9.118],[0,7.879],[4.514,2.656],[0.089,0],[7.17,-4.16],[5.224,-9.118],[0,-7.88],[-1.682,-0.973]],"v":[[13.013,-33.995],[1.505,-30.454],[-18.06,-9.738],[-26.205,17.529],[-19.21,33.818],[-1.594,31.782],[-1.416,31.693],[17.882,11.066],[26.027,-16.2],[18.945,-32.49]],"c":true},"ix":2},"nm":"Path 2","mn":"ADBE Vector Shape - Group","hd":false},{"ty":"mm","mm":1,"nm":"Merge Paths 1","mn":"ADBE Vector Filter - Merge","hd":false},{"ty":"st","c":{"a":0,"k":[0,0,0,1],"ix":3},"o":{"a":0,"k":100,"ix":4},"w":{"a":0,"k":0.4,"ix":5},"lc":1,"lj":1,"ml":10,"bm":0,"nm":"Stroke 1","mn":"ADBE Vector Graphic - Stroke","hd":false},{"ty":"fl","c":{"a":0,"k":[0,0,0,1],"ix":4},"o":{"a":0,"k":100,"ix":5},"r":1,"bm":0,"nm":"Fill 1","mn":"ADBE Vector Graphic - Fill","hd":false},{"ty":"tr","p":{"a":0,"k":[33.313,42.52],"ix":2},"a":{"a":0,"k":[0,0],"ix":1},"s":{"a":0,"k":[100,100],"ix":3},"r":{"a":0,"k":0,"ix":6},"o":{"a":0,"k":100,"ix":7},"sk":{"a":0,"k":0,"ix":4},"sa":{"a":0,"k":0,"ix":5},"nm":"Transform"}],"nm":"Group 1","np":5,"cix":2,"bm":0,"ix":1,"mn":"ADBE Vector Group","hd":false}],"ip":0,"op":300,"st":0,"bm":0},{"ddd":0,"ind":2,"ty":4,"nm":"person-top-face-face Outlines","parent":8,"sr":1,"ks":{"o":{"a":0,"k":100,"ix":11},"r":{"a":0,"k":0,"ix":10},"p":{"a":0,"k":[73.324,-15.34,0],"ix":2},"a":{"a":0,"k":[29.464,39.069,0],"ix":1},"s":{"a":0,"k":[100,100,100],"ix":6}},"ao":0,"shapes":[{"ty":"gr","it":[{"ind":0,"ty":"sh","ix":1,"ks":{"a":0,"k":{"i":[[-8.056,4.692],[-5.223,9.119],[0,9.295],[5.312,3.099],[8.056,-4.692],[5.223,-9.207],[0,-9.384],[-5.312,-3.098]],"o":[[8.056,-4.692],[5.312,-9.118],[0,-9.296],[-5.312,-3.098],[-8.056,4.692],[-5.312,9.119],[0,9.296],[5.312,2.833]],"v":[[0,33.773],[20.627,11.995],[29.214,-16.775],[20.627,-35.722],[0,-33.684],[-20.627,-11.818],[-29.214,17.041],[-20.627,35.986]],"c":true},"ix":2},"nm":"Path 1","mn":"ADBE Vector Shape - 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LehrerApp.Desktop/LehrerApp.Desktop.csproj

@@ -18,6 +18,7 @@
     <PackageReference Include="Avalonia.Themes.Fluent" />
     <PackageReference Include="Avalonia.Fonts.Inter" />
     <PackageReference Include="Avalonia.Controls.DataGrid" />
+    <PackageReference Include="Avalonia.Labs.Lottie" />
     <PackageReference Include="CommunityToolkit.Mvvm" />
     <PackageReference Include="Microsoft.Extensions.DependencyInjection" />
     <PackageReference Include="QuestPDF" />

LehrerApp.Desktop/ViewModels/Groups/StudentGroupGeneratorViewModel.cs

@@ -7,7 +7,7 @@ using System.Collections.ObjectModel;
 
 namespace LehrerApp.Desktop.ViewModels.Groups;
 
-public sealed record StudentGroupMember(string Name);
+public sealed record StudentGroupMember(Guid Id, string Name);
 public sealed record StudentPairCandidate(Guid Id, string Name);
 
 public sealed class StudentPairRule
@@ -29,8 +29,9 @@ public sealed class StudentPairRule
         FirstId == first && SecondId == second || FirstId == second && SecondId == first;
 }
 
-public sealed class GeneratedStudentGroup
+public sealed partial class GeneratedStudentGroup : ObservableObject
 {
+    [ObservableProperty] private bool _isDropTarget;
     public string Title { get; }
     public ObservableCollection<StudentGroupMember> Members { get; } = [];
 
@@ -39,7 +40,13 @@ public sealed class GeneratedStudentGroup
         Title = $"Gruppe {number}";
         foreach (var student in students.OrderBy(s => s.LastName, StringComparer.CurrentCultureIgnoreCase)
                      .ThenBy(s => s.FirstName, StringComparer.CurrentCultureIgnoreCase))
-            Members.Add(new StudentGroupMember(student.FullName));
+            Members.Add(new StudentGroupMember(student.Id, student.FullName));
+    }
+
+    public GeneratedStudentGroup(int number, IEnumerable<StudentGroupMember> members)
+    {
+        Title = $"Gruppe {number}";
+        foreach (var member in members) Members.Add(member);
     }
 }
 
@@ -55,10 +62,12 @@ public partial class StudentGroupGeneratorViewModel : ObservableObject
     private readonly IParticipationRepository _participation;
     private readonly IGradeRepository _grades;
     private readonly IGroupRepository _groupRepository;
+    private readonly IStudentGroupPlanRepository? _savedPlans;
     private readonly Random _random;
     private readonly List<Student> _participants = [];
     private readonly Dictionary<Guid, double?> _performance = [];
     private readonly HashSet<Guid> _supportStudentIds = [];
+    private Guid? _editingPlanId;
     private string _attendanceWarning = "";
 
     [ObservableProperty] private StudentDrawGroup? _selectedGroup;
@@ -77,14 +86,24 @@ public partial class StudentGroupGeneratorViewModel : ObservableObject
     [ObservableProperty] private string _statusText = "Optionen wählen und Gruppen zusammenstellen.";
     [ObservableProperty] private string _warningText = "";
     [ObservableProperty] private bool _hasGeneratedGroups;
+    [ObservableProperty] private StudentGroupPlan? _selectedSavedPlan;
+    [ObservableProperty] private string _planName = "";
+    [ObservableProperty] private string _saveStatus = "";
+    [ObservableProperty] private bool _hasUnsavedChanges;
 
     public ObservableCollection<StudentDrawGroup> Groups { get; } = [];
     public ObservableCollection<GeneratedStudentGroup> GeneratedGroups { get; } = [];
     public ObservableCollection<StudentPairCandidate> PairCandidates { get; } = [];
     public ObservableCollection<StudentPairRule> ForcedPairs { get; } = [];
     public ObservableCollection<StudentPairRule> ExcludedPairs { get; } = [];
+    public ObservableCollection<StudentGroupPlan> SavedPlans { get; } = [];
     public string[] ParticipantModeOptions { get; } = [FutureModeLabel, AdHocModeLabel];
     public bool CanGenerate => SelectedGroup is not null && _participants.Count >= 2;
+    public bool CanSave => _savedPlans is not null && SelectedGroup is not null &&
+                           HasGeneratedGroups && !string.IsNullOrWhiteSpace(PlanName);
+    public bool CanLoadSavedPlan => SelectedSavedPlan is not null;
+    public bool CanDeleteSavedPlan => SelectedSavedPlan is not null;
+    public bool HasSavedPlans => SavedPlans.Count > 0;
     public string SizePriorityLabel => PriorityLabel(SizePriority);
     public string CountPriorityLabel => PriorityLabel(CountPriority);
     public string PerformanceDistributionLabel => PerformanceDistribution switch
@@ -106,7 +125,8 @@ public partial class StudentGroupGeneratorViewModel : ObservableObject
         IParticipationRepository participation,
         IGradeRepository grades,
         Guid? initialGroupId = null,
-        Random? random = null)
+        Random? random = null,
+        IStudentGroupPlanRepository? savedPlans = null)
     {
         _students = students;
         _groupRepository = groups;
@@ -115,9 +135,13 @@ public partial class StudentGroupGeneratorViewModel : ObservableObject
         _participation = participation;
         _grades = grades;
         _random = random ?? Random.Shared;
+        _savedPlans = savedPlans;
 
         foreach (var group in groups.GetAll().OrderBy(g => g.Name, StringComparer.CurrentCultureIgnoreCase))
             Groups.Add(new StudentDrawGroup(group.Id, group.Name));
+        if (initialGroupId is { } requestedId && Groups.All(g => g.Id != requestedId) &&
+            groups.GetById(requestedId) is { } archived)
+            Groups.Add(new StudentDrawGroup(archived.Id, $"{archived.Name} (archiviert)"));
         SelectedGroup = Groups.FirstOrDefault(g => g.Id == initialGroupId) ?? Groups.FirstOrDefault();
     }
 
@@ -126,8 +150,24 @@ public partial class StudentGroupGeneratorViewModel : ObservableObject
         ForcedPairs.Clear();
         ExcludedPairs.Clear();
         ReloadParticipants();
+        ReloadSavedPlans();
+        _editingPlanId = null;
+        PlanName = "";
     }
     partial void OnParticipantModeNameChanged(string value) => ReloadParticipants();
+    partial void OnSelectedSavedPlanChanged(StudentGroupPlan? value)
+    {
+        OnPropertyChanged(nameof(CanLoadSavedPlan));
+        OnPropertyChanged(nameof(CanDeleteSavedPlan));
+        LoadSavedPlanCommand.NotifyCanExecuteChanged();
+        DeleteSavedPlanCommand.NotifyCanExecuteChanged();
+    }
+    partial void OnPlanNameChanged(string value)
+    {
+        SavePlanCommand.NotifyCanExecuteChanged();
+        if (HasGeneratedGroups) HasUnsavedChanges = true;
+    }
+    partial void OnHasGeneratedGroupsChanged(bool value) => SavePlanCommand.NotifyCanExecuteChanged();
     partial void OnTargetGroupSizeChanged(int value) => InvalidateResult();
     partial void OnTargetGroupCountChanged(int value) => InvalidateResult();
     partial void OnSizePriorityChanged(double value)
@@ -177,11 +217,118 @@ public partial class StudentGroupGeneratorViewModel : ObservableObject
             GeneratedGroups.Add(new GeneratedStudentGroup(i + 1, assignments[i]));
 
         HasGeneratedGroups = true;
+        _editingPlanId = null;
+        SelectedSavedPlan = null;
+        PlanName = $"Einteilung {DateTime.Now:dd.MM.yyyy HH:mm:ss}";
+        HasUnsavedChanges = true;
+        SaveStatus = "Noch nicht gespeichert.";
         StatusText = $"{_participants.Count} Schüler · {groupCount} Gruppen · Größen " +
                      string.Join("/", capacities.Distinct().OrderBy(x => x));
         UpdateWarning(groupCount, assignments);
     }
 
+    [RelayCommand(CanExecute = nameof(CanSave))]
+    private void SavePlan()
+    {
+        if (_savedPlans is null || SelectedGroup is null) return;
+        var plan = new StudentGroupPlan
+        {
+            Id = _editingPlanId ?? Guid.NewGuid(),
+            GroupId = SelectedGroup.Id,
+            Name = PlanName,
+            Groups = GeneratedGroups.Select(group => new StudentGroupPlanGroup
+            {
+                StudentIds = group.Members.Select(member => member.Id).ToList(),
+            }).ToList(),
+        };
+        try
+        {
+            _savedPlans.Save(plan);
+            _editingPlanId = plan.Id;
+            ReloadSavedPlans(plan.Id);
+            HasUnsavedChanges = false;
+            SaveStatus = "Einteilung gespeichert.";
+        }
+        catch (Exception ex) when (ex is ArgumentException or InvalidOperationException)
+        {
+            SaveStatus = ex.Message;
+        }
+    }
+
+    [RelayCommand(CanExecute = nameof(CanLoadSavedPlan))]
+    private void LoadSavedPlan()
+    {
+        if (_savedPlans is null || SelectedSavedPlan is not { } selected ||
+            SelectedGroup?.Id != selected.GroupId) return;
+        var plan = _savedPlans.GetById(selected.Id);
+        if (plan is null) { ReloadSavedPlans(); return; }
+        _editingPlanId = plan.Id;
+
+        var missing = 0;
+        GeneratedGroups.Clear();
+        foreach (var group in plan.Groups ?? [])
+        {
+            var members = new List<StudentGroupMember>();
+            foreach (var id in group.StudentIds ?? [])
+            {
+                if (_students.GetById(id) is { } student)
+                    members.Add(new StudentGroupMember(id, student.FullName));
+                else missing++;
+            }
+            GeneratedGroups.Add(new GeneratedStudentGroup(GeneratedGroups.Count + 1, members));
+        }
+        HasGeneratedGroups = GeneratedGroups.Count > 0;
+        PlanName = plan.Name;
+        HasUnsavedChanges = missing > 0;
+        SaveStatus = missing > 0
+            ? $"{missing} nicht mehr vorhandene Schüler wurden ausgelassen. Bitte erneut speichern."
+            : "Gespeicherte Einteilung geladen.";
+        StatusText = $"{GeneratedGroups.Sum(group => group.Members.Count)} Schüler · " +
+                     $"{GeneratedGroups.Count} Gruppen · gespeichert am {plan.UpdatedAt.ToLocalTime():dd.MM.yyyy}";
+        WarningText = missing > 0 ? SaveStatus : "";
+    }
+
+    [RelayCommand(CanExecute = nameof(CanDeleteSavedPlan))]
+    private void DeleteSavedPlan()
+    {
+        if (_savedPlans is null || SelectedSavedPlan is not { } plan) return;
+        _savedPlans.Delete(plan.Id);
+        var deletedCurrent = _editingPlanId == plan.Id;
+        if (deletedCurrent) _editingPlanId = null;
+        ReloadSavedPlans();
+        if (deletedCurrent) HasUnsavedChanges = HasGeneratedGroups;
+        SaveStatus = "Gespeicherte Einteilung gelöscht.";
+    }
+
+    public bool MoveStudent(StudentGroupMember member, GeneratedStudentGroup target)
+    {
+        if (!HasGeneratedGroups || !GeneratedGroups.Contains(target)) return false;
+        var source = GeneratedGroups.FirstOrDefault(group => group.Members.Contains(member));
+        if (source is null || source == target || target.Members.Any(m => m.Id == member.Id)) return false;
+        source.Members.Remove(member);
+        target.Members.Add(member);
+        HasUnsavedChanges = true;
+        SaveStatus = "Änderungen noch nicht gespeichert.";
+        StatusText = $"{GeneratedGroups.Sum(group => group.Members.Count)} Schüler · " +
+                     $"{GeneratedGroups.Count} Gruppen · manuell angepasst";
+        var assignments = GeneratedGroups.Select(group => group.Members
+            .Select(m => _students.GetById(m.Id)).OfType<Student>().ToList()).ToList();
+        UpdateWarning(GeneratedGroups.Count, assignments);
+        return true;
+    }
+
+    private void ReloadSavedPlans(Guid? selectedId = null)
+    {
+        SavedPlans.Clear();
+        SelectedSavedPlan = null;
+        if (_savedPlans is not null && SelectedGroup is not null)
+        {
+            foreach (var plan in _savedPlans.GetByGroup(SelectedGroup.Id)) SavedPlans.Add(plan);
+            SelectedSavedPlan = SavedPlans.FirstOrDefault(plan => plan.Id == selectedId);
+        }
+        OnPropertyChanged(nameof(HasSavedPlans));
+    }
+
     private void ReloadParticipants()
     {
         _participants.Clear();
@@ -385,6 +532,8 @@ public partial class StudentGroupGeneratorViewModel : ObservableObject
     {
         GeneratedGroups.Clear();
         HasGeneratedGroups = false;
+        HasUnsavedChanges = false;
+        SaveStatus = "";
         StatusText = _participants.Count >= 2
             ? $"{_participants.Count} Schüler stehen zur Einteilung bereit."
             : "Für eine Gruppeneinteilung werden mindestens zwei Schüler benötigt.";

LehrerApp.Desktop/ViewModels/Groups/TeachingModeViewModel.cs

@@ -22,6 +22,7 @@ public class TeachingModeViewModel
 {
     public TeachingTimelineViewModel Timeline { get; }
     public string GroupName { get; }
+    public DateOnly LessonDate { get; }
     public LessonViewerViewModel LessonInfo { get; }
     public SeatingPlanTabViewModel SeatingPlan { get; }
     /// <summary>Nutzer-Feedback: die Schnellbewertungs-Dialoge für Mitarbeit/Anwesenheit-Hausaufgabe
@@ -41,6 +42,7 @@ public class TeachingModeViewModel
         TeachingModeOutstandingHomeworkViewModel? outstandingHomework = null)
     {
         GroupName = group.Name;
+        LessonDate = lesson.Date;
         Timeline = new TeachingTimelineViewModel(lesson, lessons, !group.IsActive);
         LessonInfo = new LessonViewerViewModel(lesson, alternativePaths);
 

LehrerApp.Desktop/Views/Groups/RandomStudentPickerWindow.axaml

@@ -1,10 +1,11 @@
 <Window xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:vm="clr-namespace:LehrerApp.Desktop.ViewModels.Groups"
+        xmlns:lottie="clr-namespace:Avalonia.Labs.Lottie;assembly=Avalonia.Labs.Lottie"
         x:Class="LehrerApp.Desktop.Views.Groups.RandomStudentPickerWindow"
         x:DataType="vm:RandomStudentPickerViewModel"
         Title="Schüler ziehen"
-        Width="430" MinHeight="390"
+        Width="430" MinHeight="430"
         SizeToContent="Height"
         CanResize="False"
         WindowStartupLocation="CenterScreen">
@@ -16,12 +17,13 @@
         <TextBlock Text="Eigenständiges Fenster für die Bildschirmfreigabe"
                    FontSize="12" Opacity="0.55"/>
       </StackPanel>
-      <Button Grid.Column="1" Content="↺" Command="{Binding ResetCommand}"
+      <Button Grid.Column="1" x:Name="ResetButton" Content="↺" Command="{Binding ResetCommand}"
               ToolTip.Tip="Ziehung zurücksetzen" FontSize="18"
               Width="38" Height="38"/>
     </Grid>
 
-    <Border Grid.Row="1" x:Name="RevealCard"
+    <Grid Grid.Row="1" MinHeight="230">
+    <Border x:Name="RevealCard"
             MinHeight="190" Padding="24"
             Background="{DynamicResource AppAccentSoftBackgroundBrush}"
             BorderBrush="{DynamicResource AppFilterActiveBorderBrush}"
@@ -42,13 +44,19 @@
                    TextAlignment="Center" TextWrapping="Wrap" FontSize="12" Opacity="0.7"/>
       </StackPanel>
     </Border>
+    <lottie:Lottie x:Name="WheelAnimation"
+                   Path="/Assets/Animations/LotterySpinWheel.json"
+                   RepeatCount="-1" AutoPlay="False"
+                   Width="220" Height="220" HorizontalAlignment="Center"
+                   VerticalAlignment="Center" IsVisible="False"/>
+    </Grid>
 
     <Button Grid.Row="2" Content="🎲  Ziehen" x:Name="DrawButton"
             IsEnabled="{Binding CanDraw}" Click="OnDraw"
             HorizontalAlignment="Stretch" HorizontalContentAlignment="Center"
             FontSize="18" FontWeight="SemiBold" Height="54" Margin="0,16,0,12"/>
 
-    <Expander Grid.Row="3" Header="Optionen" IsExpanded="False">
+    <Expander Grid.Row="3" x:Name="OptionsExpander" Header="Optionen" IsExpanded="False">
       <StackPanel Spacing="10" Margin="0,10,0,0">
         <TextBlock Text="Lerngruppe" FontSize="12" Opacity="0.7"/>
         <ComboBox ItemsSource="{Binding Groups}" SelectedItem="{Binding SelectedGroup}"

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

@@ -1,26 +1,60 @@
 using Avalonia.Controls;
 using Avalonia.Interactivity;
+using Avalonia.Labs.Lottie;
 using LehrerApp.Desktop.ViewModels.Groups;
 
 namespace LehrerApp.Desktop.Views.Groups;
 
 public partial class RandomStudentPickerWindow : Window
 {
-    private bool _isAnimating;
+    private bool _isSpinning;
+    private DateTime _spinStartedAt;
 
     public RandomStudentPickerWindow() => InitializeComponent();
 
     private async void OnDraw(object? sender, RoutedEventArgs e)
     {
-        if (_isAnimating || DataContext is not RandomStudentPickerViewModel vm ||
+        if (DataContext is not RandomStudentPickerViewModel vm ||
             !vm.DrawCommand.CanExecute(null)) return;
 
-        _isAnimating = true;
         var card = this.FindControl<Border>("RevealCard");
-        if (card is not null) card.Opacity = 0.15;
-        await Task.Delay(150);
+        var wheel = this.FindControl<Lottie>("WheelAnimation");
+        var button = this.FindControl<Button>("DrawButton");
+        if (card is null || wheel is null || button is null) return;
+
+        if (!_isSpinning)
+        {
+            _isSpinning = true;
+            _spinStartedAt = DateTime.UtcNow;
+            card.IsVisible = false;
+            wheel.IsVisible = true;
+            this.FindControl<Expander>("OptionsExpander")!.IsEnabled = false;
+            this.FindControl<Button>("ResetButton")!.IsEnabled = false;
+            button.Content = "Dreht …";
+            // Erst nach dem Layoutwechsel starten, damit das erste Bild sichtbar ist.
+            await Task.Yield();
+            if (!_isSpinning) return;
+            wheel.Start();
+            button.Content = "Ergebnis anzeigen";
+            return;
+        }
+
+        // Ein Doppelklick soll die Ziehung nicht unbemerkt sofort auflösen.
+        if (DateTime.UtcNow - _spinStartedAt < TimeSpan.FromSeconds(1.2)) return;
+        wheel.Stop();
+        wheel.IsVisible = false;
         vm.DrawCommand.Execute(null);
-        if (card is not null) card.Opacity = 1;
-        _isAnimating = false;
+        card.IsVisible = true;
+        this.FindControl<Expander>("OptionsExpander")!.IsEnabled = true;
+        this.FindControl<Button>("ResetButton")!.IsEnabled = true;
+        button.Content = "🎲  Ziehen";
+        _isSpinning = false;
+    }
+
+    protected override void OnClosed(EventArgs e)
+    {
+        _isSpinning = false;
+        this.FindControl<Lottie>("WheelAnimation")?.Stop();
+        base.OnClosed(e);
     }
 }

LehrerApp.Desktop/Views/Groups/StudentGroupGeneratorWindow.axaml

@@ -1,12 +1,21 @@
 <Window xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:vm="clr-namespace:LehrerApp.Desktop.ViewModels.Groups"
+        xmlns:models="clr-namespace:LehrerApp.Core.Models;assembly=LehrerApp.Core"
+        xmlns:lottie="clr-namespace:Avalonia.Labs.Lottie;assembly=Avalonia.Labs.Lottie"
         x:Class="LehrerApp.Desktop.Views.Groups.StudentGroupGeneratorWindow"
         x:DataType="vm:StudentGroupGeneratorViewModel"
         Title="Gruppen zusammenstellen"
         Width="780" Height="650" MinWidth="620" MinHeight="480"
         WindowStartupLocation="CenterScreen">
 
+  <Window.Styles>
+    <Style Selector="Border.studentgroup.droptarget">
+      <Setter Property="BorderBrush" Value="{DynamicResource AppAccentTextBrush}"/>
+      <Setter Property="BorderThickness" Value="2"/>
+    </Style>
+  </Window.Styles>
+
   <Grid RowDefinitions="Auto,*,Auto,Auto" Margin="24">
     <StackPanel Grid.Row="0" Spacing="3" Margin="0,0,0,16">
       <TextBlock Text="Gruppen zusammenstellen" Classes="dialogtitle"/>
@@ -14,7 +23,7 @@
                  FontSize="12" Opacity="0.55"/>
     </StackPanel>
 
-    <ScrollViewer Grid.Row="1">
+    <ScrollViewer Grid.Row="1" x:Name="ResultsScrollViewer">
       <Grid x:Name="GroupResults">
         <Grid.Transitions>
           <Transitions>
@@ -40,17 +49,26 @@
           </ItemsControl.ItemsPanel>
           <ItemsControl.ItemTemplate>
             <DataTemplate x:DataType="vm:GeneratedStudentGroup">
-              <Border Width="220" Margin="7" Padding="16"
+              <Border Width="220" Margin="7" Padding="16" Classes="studentgroup"
+                      Classes.droptarget="{Binding IsDropTarget}"
                       Background="{DynamicResource AppCardBackgroundBrush}"
                       BorderBrush="{DynamicResource AppCardBorderBrush}"
-                      BorderThickness="1" CornerRadius="12">
+                      BorderThickness="1" CornerRadius="12"
+                      DragDrop.AllowDrop="True" DragDrop.DragEnter="OnGroupDragEnter"
+                      DragDrop.DragLeave="OnGroupDragLeave" DragDrop.DragOver="OnGroupDragOver"
+                      DragDrop.Drop="OnGroupDrop">
                 <StackPanel Spacing="9">
                   <TextBlock Text="{Binding Title}" FontSize="16" FontWeight="SemiBold"
                              Foreground="{DynamicResource AppAccentTextBrush}"/>
                   <ItemsControl ItemsSource="{Binding Members}">
                     <ItemsControl.ItemTemplate>
                       <DataTemplate x:DataType="vm:StudentGroupMember">
-                        <TextBlock Text="{Binding Name}" Margin="0,3" TextWrapping="Wrap"/>
+                        <Border Background="{DynamicResource AppChipBackgroundBrush}"
+                                CornerRadius="6" Padding="8,5" Margin="0,3"
+                                PointerPressed="OnMemberPressed" PointerMoved="OnMemberMoved"
+                                PointerReleased="OnMemberReleased">
+                          <TextBlock Text="{Binding Name}" TextWrapping="Wrap"/>
+                        </Border>
                       </DataTemplate>
                     </ItemsControl.ItemTemplate>
                   </ItemsControl>
@@ -61,11 +79,41 @@
         </ItemsControl>
       </Grid>
     </ScrollViewer>
+    <lottie:Lottie Grid.Row="1" x:Name="TeamworkAnimation"
+                   Path="/Assets/Animations/Teamwork.json"
+                   RepeatCount="-1" AutoPlay="False"
+                   Width="270" Height="270" HorizontalAlignment="Center"
+                   VerticalAlignment="Center" IsVisible="False"/>
 
     <StackPanel Grid.Row="2" Spacing="8" Margin="0,12,0,10">
-      <Button Content="Gruppen zusammenstellen" Click="OnGenerate"
+      <Button x:Name="GenerateButton" Content="Gruppen zusammenstellen" Click="OnGenerate"
               IsEnabled="{Binding CanGenerate}" HorizontalAlignment="Stretch"
               HorizontalContentAlignment="Center" Height="48" FontSize="16" FontWeight="SemiBold"/>
+      <StackPanel x:Name="PlanActions" Spacing="8">
+      <TextBlock Text="Schüler zwischen den Gruppenkarten ziehen, um die Einteilung anzupassen."
+                 FontSize="11" Opacity="0.65" IsVisible="{Binding HasGeneratedGroups}"/>
+      <Grid ColumnDefinitions="*,10,Auto,8,Auto" IsVisible="{Binding HasSavedPlans}">
+        <ComboBox ItemsSource="{Binding SavedPlans}" SelectedItem="{Binding SelectedSavedPlan}"
+                  PlaceholderText="Gespeicherte Einteilung auswählen">
+          <ComboBox.ItemTemplate>
+            <DataTemplate x:DataType="models:StudentGroupPlan">
+              <TextBlock Text="{Binding Name}"/>
+            </DataTemplate>
+          </ComboBox.ItemTemplate>
+        </ComboBox>
+        <Button Grid.Column="2" Content="Laden" Click="OnLoadSavedPlan"
+                IsEnabled="{Binding CanLoadSavedPlan}"/>
+        <Button Grid.Column="4" Content="Löschen" Click="OnDeleteSavedPlan"
+                IsEnabled="{Binding CanDeleteSavedPlan}"/>
+      </Grid>
+      <Grid ColumnDefinitions="*,10,Auto" IsVisible="{Binding HasGeneratedGroups}">
+        <TextBox Text="{Binding PlanName, Mode=TwoWay}" PlaceholderText="Name der Einteilung"/>
+        <Button Grid.Column="2" Content="Speichern" Command="{Binding SavePlanCommand}"/>
+      </Grid>
+      <TextBlock Text="{Binding SaveStatus}" FontSize="11" Opacity="0.7" TextWrapping="Wrap"
+                 IsVisible="{Binding SaveStatus, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+      </StackPanel>
+      <StackPanel x:Name="ResultSummary" Spacing="8">
       <TextBlock Text="{Binding StatusText}" HorizontalAlignment="Center" Opacity="0.65"
                  IsVisible="{Binding HasGeneratedGroups}"/>
       <Border Background="{DynamicResource AppChipBackgroundBrush}" CornerRadius="8" Padding="10,7"
@@ -74,8 +122,9 @@
                    Foreground="{DynamicResource AppStatusWarningBrush}"/>
       </Border>
       </StackPanel>
+    </StackPanel>
 
-    <Expander Grid.Row="3" Header="Optionen" IsExpanded="False">
+    <Expander Grid.Row="3" x:Name="OptionsExpander" Header="Optionen" IsExpanded="False">
       <ScrollViewer MaxHeight="340">
         <StackPanel Spacing="11" Margin="0,10,6,4">
           <Grid ColumnDefinitions="*,16,*">

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

@@ -1,25 +1,204 @@
 using Avalonia.Controls;
+using Avalonia.Input;
 using Avalonia.Interactivity;
+using Avalonia.Labs.Lottie;
+using Avalonia.Threading;
+using LehrerApp.Core.Interfaces;
 using LehrerApp.Desktop.ViewModels.Groups;
+using LehrerApp.Desktop.Views.Shared;
+using Microsoft.Extensions.DependencyInjection;
 
 namespace LehrerApp.Desktop.Views.Groups;
 
 public partial class StudentGroupGeneratorWindow : Window
 {
-    private bool _isAnimating;
+    private bool _isSpinning;
+    private DateTime _spinStartedAt;
+    private StudentGroupMember? _dragCandidate;
+    private PointerPressedEventArgs? _dragTrigger;
+    private Avalonia.Point _pressPosition;
+    private StudentGroupMember? _draggedMember;
+    private GeneratedStudentGroup? _pendingDropTarget;
 
     public StudentGroupGeneratorWindow() => InitializeComponent();
 
+    public static StudentGroupGeneratorWindow Create(Guid? initialGroupId, bool useTodayAttendance = false)
+    {
+        var vm = new StudentGroupGeneratorViewModel(
+            App.Services.GetRequiredService<IStudentRepository>(),
+            App.Services.GetRequiredService<IGroupRepository>(),
+            App.Services.GetRequiredService<IGroupMembershipRepository>(),
+            App.Services.GetRequiredService<IParticipationSessionRepository>(),
+            App.Services.GetRequiredService<IParticipationRepository>(),
+            App.Services.GetRequiredService<IGradeRepository>(),
+            initialGroupId,
+            savedPlans: App.Services.GetRequiredService<IStudentGroupPlanRepository>());
+        if (useTodayAttendance)
+            vm.ParticipantModeName = StudentGroupGeneratorViewModel.AdHocModeLabel;
+        return new StudentGroupGeneratorWindow { DataContext = vm };
+    }
+
     private async void OnGenerate(object? sender, RoutedEventArgs e)
     {
-        if (_isAnimating || DataContext is not StudentGroupGeneratorViewModel vm ||
+        if (DataContext is not StudentGroupGeneratorViewModel vm ||
             !vm.GenerateCommand.CanExecute(null)) return;
-        _isAnimating = true;
-        var results = this.FindControl<Grid>("GroupResults");
-        if (results is not null) results.Opacity = 0.15;
-        await Task.Delay(140);
+        var results = this.FindControl<ScrollViewer>("ResultsScrollViewer");
+        var teamwork = this.FindControl<Lottie>("TeamworkAnimation");
+        var button = this.FindControl<Button>("GenerateButton");
+        var options = this.FindControl<Expander>("OptionsExpander");
+        var summary = this.FindControl<StackPanel>("ResultSummary");
+        var actions = this.FindControl<StackPanel>("PlanActions");
+        if (results is null || teamwork is null || button is null || options is null ||
+            summary is null || actions is null) return;
+
+        if (!_isSpinning)
+        {
+            _isSpinning = true;
+            _spinStartedAt = DateTime.UtcNow;
+            results.IsVisible = false;
+            actions.IsVisible = false;
+            summary.IsVisible = false;
+            teamwork.IsVisible = true;
+            options.IsEnabled = false;
+            button.Content = "Teamwork läuft …";
+            // Nach dem Layoutwechsel starten, damit der erste Frame sichtbar ist.
+            await Task.Yield();
+            if (!_isSpinning) return;
+            teamwork.Start();
+            button.Content = "Ergebnis anzeigen";
+            return;
+        }
+
+        // Ein Doppelklick soll die Animation nicht sofort wieder schließen.
+        if (DateTime.UtcNow - _spinStartedAt < TimeSpan.FromSeconds(1.2)) return;
+        try
+        {
             vm.GenerateCommand.Execute(null);
-        if (results is not null) results.Opacity = 1;
-        _isAnimating = false;
+        }
+        finally
+        {
+            teamwork.Stop();
+            teamwork.IsVisible = false;
+            results.IsVisible = true;
+            actions.IsVisible = true;
+            summary.IsVisible = true;
+            options.IsEnabled = true;
+            button.Content = "Gruppen zusammenstellen";
+            _isSpinning = false;
+        }
+    }
+
+    private void OnMemberPressed(object? sender, PointerPressedEventArgs e)
+    {
+        if (_isSpinning || sender is not Control { DataContext: StudentGroupMember member } control ||
+            !e.GetCurrentPoint(control).Properties.IsLeftButtonPressed) return;
+        _dragCandidate = member;
+        _dragTrigger = e;
+        _pressPosition = e.GetPosition(this);
+    }
+
+    private async void OnLoadSavedPlan(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is not StudentGroupGeneratorViewModel vm ||
+            !vm.LoadSavedPlanCommand.CanExecute(null)) return;
+        if (vm.HasUnsavedChanges)
+        {
+            var dialog = new ConfirmDialog
+            {
+                DataContext = new ConfirmDialogInfo
+                {
+                    Title = "Ungespeicherte Einteilung ersetzen?",
+                    Message = "Die aktuelle Einteilung und manuelle Änderungen werden beim Laden verworfen.",
+                    ConfirmText = "Gespeicherte Einteilung laden",
+                },
+            };
+            if (!await dialog.ShowDialog<bool>(this)) return;
+        }
+        vm.LoadSavedPlanCommand.Execute(null);
+    }
+
+    private async void OnDeleteSavedPlan(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is not StudentGroupGeneratorViewModel vm ||
+            !vm.DeleteSavedPlanCommand.CanExecute(null)) return;
+        var dialog = new ConfirmDialog
+        {
+            DataContext = new ConfirmDialogInfo
+            {
+                Title = "Einteilung löschen?",
+                Message = $"Die gespeicherte Einteilung „{vm.SelectedSavedPlan!.Name}“ wird gelöscht.",
+                ConfirmText = "Löschen",
+            },
+        };
+        if (await dialog.ShowDialog<bool>(this)) vm.DeleteSavedPlanCommand.Execute(null);
+    }
+
+    private async void OnMemberMoved(object? sender, PointerEventArgs e)
+    {
+        if (_dragCandidate is null || _dragTrigger is null ||
+            !e.GetCurrentPoint(this).Properties.IsLeftButtonPressed) return;
+        var position = e.GetPosition(this);
+        if (Math.Abs(position.X - _pressPosition.X) < 6 &&
+            Math.Abs(position.Y - _pressPosition.Y) < 6) return;
+
+        _draggedMember = _dragCandidate;
+        _pendingDropTarget = null;
+        _dragCandidate = null;
+        var trigger = _dragTrigger;
+        _dragTrigger = null;
+        var data = new DataTransfer();
+        data.Add(DataTransferItem.CreateText("LehrerApp-Gruppeneinteilung"));
+        var effect = await DragDrop.DoDragDropAsync(trigger, data, DragDropEffects.Move);
+        var member = _draggedMember;
+        var target = _pendingDropTarget;
+        _draggedMember = null;
+        _pendingDropTarget = null;
+        if ((effect & DragDropEffects.Move) == 0 || member is null || target is null) return;
+        // Die Quelle erst verändern, wenn Avalonia den Drop vollständig verarbeitet hat.
+        Dispatcher.UIThread.Post(() =>
+        {
+            if (DataContext is StudentGroupGeneratorViewModel vm) vm.MoveStudent(member, target);
+        }, DispatcherPriority.Background);
+    }
+
+    private void OnMemberReleased(object? sender, PointerReleasedEventArgs e)
+    {
+        _dragCandidate = null;
+        _dragTrigger = null;
+    }
+
+    private bool CanDropOn(GeneratedStudentGroup target) =>
+        !_isSpinning && _draggedMember is { } member &&
+        !target.Members.Any(existing => existing.Id == member.Id);
+
+    private void OnGroupDragEnter(object? sender, DragEventArgs e)
+    {
+        if (sender is Border { DataContext: GeneratedStudentGroup target } && CanDropOn(target))
+            target.IsDropTarget = true;
+    }
+
+    private void OnGroupDragLeave(object? sender, DragEventArgs e)
+    {
+        if (sender is Border { DataContext: GeneratedStudentGroup target }) target.IsDropTarget = false;
+    }
+
+    private void OnGroupDragOver(object? sender, DragEventArgs e) =>
+        e.DragEffects = sender is Border { DataContext: GeneratedStudentGroup target } && CanDropOn(target)
+            ? DragDropEffects.Move : DragDropEffects.None;
+
+    private void OnGroupDrop(object? sender, DragEventArgs e)
+    {
+        if (sender is not Border { DataContext: GeneratedStudentGroup target }) return;
+        target.IsDropTarget = false;
+        if (!CanDropOn(target)) { e.DragEffects = DragDropEffects.None; return; }
+        _pendingDropTarget = target;
+        e.DragEffects = DragDropEffects.Move;
+    }
+
+    protected override void OnClosed(EventArgs e)
+    {
+        _isSpinning = false;
+        this.FindControl<Lottie>("TeamworkAnimation")?.Stop();
+        base.OnClosed(e);
     }
 }

LehrerApp.Desktop/Views/Groups/TeachingModeWindow.axaml

@@ -52,6 +52,8 @@
         <Button Content="Hausaufgaben kontrollieren" Command="{Binding SeatingPlan.CheckHomeworkCommand}" IsEnabled="{Binding SeatingPlan.IsEditable}"/>
         <Button Content="Kontrolle beenden" Command="{Binding SeatingPlan.EndQuickCheckCommand}" IsVisible="{Binding SeatingPlan.IsQuickMode}"/>
         <Button Content="Listenansicht …" Command="{Binding Participation.StatusQuickInputCommand}" ToolTip.Tip="Auch Schüler ohne Sitzplatz erfassen."/>
+        <Button Content="Gruppen zusammenstellen …" Click="OnOpenStudentGroups"
+                ToolTip.Tip="Gruppen für diese Lerngruppe ziehen, bearbeiten und später wieder laden."/>
         <Button Content="Vollbild ↔" Click="OnFullScreen" ToolTip.Tip="Vollbild umschalten (F11); mit Escape verlassen."/>
         <Button Content="Zur Mitarbeit" Command="{Binding LessonInfo.NavigateToParticipationCommand}"
                 ToolTip.Tip="Schließt den Unterrichtsmodus und springt zum Tab 'Mitarbeit' der Lerngruppe."/>

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

@@ -15,6 +15,7 @@ public partial class TeachingModeWindow : Window
     private static readonly Dictionary<Guid, TeachingModeWindow> OpenWindows = [];
     private readonly DispatcherTimer _clock = new() { Interval = TimeSpan.FromSeconds(1) };
     private WindowState _previousState = WindowState.Maximized;
+    private StudentGroupGeneratorWindow? _studentGroupGeneratorWindow;
 
     public static void Open(Lesson lesson)
     {
@@ -66,6 +67,20 @@ public partial class TeachingModeWindow : Window
     }
     private void OnFullScreen(object? sender, RoutedEventArgs e) => ToggleFullScreen();
 
+    private void OnOpenStudentGroups(object? sender, RoutedEventArgs e)
+    {
+        if (_studentGroupGeneratorWindow is not null)
+        {
+            _studentGroupGeneratorWindow.Activate();
+            return;
+        }
+        if (DataContext is not TeachingModeViewModel vm) return;
+        _studentGroupGeneratorWindow = StudentGroupGeneratorWindow.Create(vm.LessonInfo.GroupId,
+            useTodayAttendance: vm.LessonDate == DateOnly.FromDateTime(DateTime.Today));
+        _studentGroupGeneratorWindow.Closed += (_, _) => _studentGroupGeneratorWindow = null;
+        _studentGroupGeneratorWindow.Show(this);
+    }
+
     protected override void OnDataContextChanged(EventArgs e)
     {
         base.OnDataContextChanged(e);

LehrerApp.Desktop/Views/MainWindow.axaml.cs

@@ -103,15 +103,7 @@ public partial class MainWindow : Window
         }
 
         var currentGroupId = (DataContext as MainWindowViewModel)?.CurrentGroupDetail?.Group?.Id;
-        var vm = new StudentGroupGeneratorViewModel(
-            App.Services.GetRequiredService<IStudentRepository>(),
-            App.Services.GetRequiredService<IGroupRepository>(),
-            App.Services.GetRequiredService<IGroupMembershipRepository>(),
-            App.Services.GetRequiredService<IParticipationSessionRepository>(),
-            App.Services.GetRequiredService<IParticipationRepository>(),
-            App.Services.GetRequiredService<IGradeRepository>(),
-            currentGroupId);
-        _studentGroupGeneratorWindow = new StudentGroupGeneratorWindow { DataContext = vm };
+        _studentGroupGeneratorWindow = StudentGroupGeneratorWindow.Create(currentGroupId);
         _studentGroupGeneratorWindow.Closed += (_, _) => _studentGroupGeneratorWindow = null;
         _studentGroupGeneratorWindow.Show();
     }

LehrerApp.Sync.Tests/EventApplierTests.cs

@@ -11,6 +11,25 @@ public sealed class EventApplierTests
     private static LiteDbContext NewInMemoryContext() => new(new MemoryStream());
     private static readonly byte[] Key = SyncCrypto.GenerateKey();
 
+    [Fact]
+    public async Task ApplyAsync_StudentGroupPlan_SynchronisiertEinteilungUndLoeschung()
+    {
+        using var db = NewInMemoryContext();
+        var applier = new EventApplier(db, Key);
+        var studentId = Guid.NewGuid();
+        var plan = new StudentGroupPlan
+        {
+            GroupId = Guid.NewGuid(), Name = "Projektwoche",
+            Groups = [new StudentGroupPlanGroup { StudentIds = [studentId] }],
+        };
+
+        await applier.ApplyAsync(MakeEvent(nameof(StudentGroupPlan), plan.Id.ToString(), "Save", plan));
+        Assert.Equal(studentId, db.StudentGroupPlans.FindById(plan.Id)!.Groups[0].StudentIds[0]);
+
+        await applier.ApplyAsync(MakeEvent(nameof(StudentGroupPlan), plan.Id.ToString(), "Delete", null));
+        Assert.Null(db.StudentGroupPlans.FindById(plan.Id));
+    }
+
     [Fact]
     public async Task ApplyAsync_Save_SchreibtEntitaetDirektInDieCollection()
     {

LehrerApp.Sync/EventApplier.cs

@@ -125,6 +125,7 @@ public class EventApplier(LiteDbContext db, byte[] syncKey, HttpClient? http = n
 
         Simple<Student>(context => context.Students);
         Simple<SeatingPlan>(context => context.SeatingPlans);
+        Simple<StudentGroupPlan>(context => context.StudentGroupPlans);
         Simple<GroupMembership>(context => context.Memberships);
         Simple<GradingKeyTemplate>(context => context.GradingKeyTemplates);
         Simple<Grade>(context => context.Grades);