Initial

2026-03-29 23:47:31 +02:00
commit 216d5d2280
75 changed files with 5702 additions and 0 deletions
--- a/LehrerApp.Sync/EventQueue.cs
+++ b/LehrerApp.Sync/EventQueue.cs
@@ -0,0 +1,129 @@
+using LiteDB;
+using LehrerApp.Sync.Models;
+
+namespace LehrerApp.Sync;
+
+/// <summary>
+/// Lokale Event-Queue in LiteDB.
+/// Jede Datenänderung erzeugt einen Event – dieser wird hier gepuffert
+/// bis er erfolgreich zum Server gepusht wurde.
+/// </summary>
+public class EventQueue : IDisposable
+{
+    private readonly LiteDatabase _db;
+    private readonly ILiteCollection<SyncEvent> _queue;
+    private readonly ILiteCollection<SyncMeta> _meta;
+    private readonly ILiteCollection<ConflictEntry> _conflicts;
+    private long _currentSequenceNr;
+
+    public EventQueue(string queueDbPath)
+    {
+        _db = new LiteDatabase(queueDbPath);
+        _queue = _db.GetCollection<SyncEvent>("queue");
+        _meta = _db.GetCollection<SyncMeta>("meta");
+        _conflicts = _db.GetCollection<ConflictEntry>("conflicts");
+
+        _queue.EnsureIndex(x => x.SequenceNr);
+        _queue.EnsureIndex(x => x.Timestamp);
+
+        // Letzte SequenceNr wiederherstellen
+        var meta = _meta.FindById("seq");
+        _currentSequenceNr = meta?.Value ?? 0;
+    }
+
+    // ── Events einreihen ──────────────────────────────────────────────────────
+
+    public SyncEvent Enqueue(
+        string entityType,
+        string entityId,
+        string operation,
+        string encryptedPayload,
+        string deviceId,
+        DeviceType deviceType)
+    {
+        var evt = new SyncEvent
+        {
+            DeviceId = deviceId,
+            DeviceType = deviceType,
+            Timestamp = DateTime.UtcNow,
+            SequenceNr = ++_currentSequenceNr,
+            EntityType = entityType,
+            EntityId = entityId,
+            Operation = operation,
+            Payload = encryptedPayload,
+        };
+
+        _queue.Insert(evt);
+        _meta.Upsert(new SyncMeta { Id = "seq", Value = _currentSequenceNr });
+
+        return evt;
+    }
+
+    // ── Ausstehende Events ────────────────────────────────────────────────────
+
+    public List<SyncEvent> GetPending(int maxBatch = 100) =>
+        _queue.Find(Query.All(nameof(SyncEvent.SequenceNr)))
+            .Take(maxBatch)
+            .ToList();
+
+    public int PendingCount() => _queue.Count();
+
+    // ── Bestätigung nach erfolgreichem Push ───────────────────────────────────
+
+    public void Acknowledge(IEnumerable<Guid> eventIds)
+    {
+        foreach (var id in eventIds)
+            _queue.Delete(id);
+    }
+
+    // ── Letzte Sync-Metadaten ─────────────────────────────────────────────────
+
+    public long GetLastServerSequenceNr() =>
+        _meta.FindById("serverSeq")?.Value ?? 0;
+
+    public void SetLastServerSequenceNr(long nr) =>
+        _meta.Upsert(new SyncMeta { Id = "serverSeq", Value = nr });
+
+    public DateTime? GetLastSyncAt()
+    {
+        var meta = _meta.FindById("lastSync");
+        return meta?.Timestamp;
+    }
+
+    public void SetLastSyncAt(DateTime timestamp) =>
+        _meta.Upsert(new SyncMeta
+        {
+            Id = "lastSync",
+            Value = 0,
+            Timestamp = timestamp
+        });
+
+    // ── Konflikte ─────────────────────────────────────────────────────────────
+
+    public void AddConflict(ConflictEntry conflict) =>
+        _conflicts.Insert(conflict);
+
+    public List<ConflictEntry> GetUnreviewedConflicts() =>
+        _conflicts.Find(c => !c.Reviewed).ToList();
+
+    public int ConflictCount() =>
+        _conflicts.Count(c => !c.Reviewed);
+
+    public void MarkConflictReviewed(Guid id)
+    {
+        var conflict = _conflicts.FindById(id);
+        if (conflict is null) return;
+        conflict.Reviewed = true;
+        _conflicts.Update(conflict);
+    }
+
+    public void Dispose() => _db.Dispose();
+}
+
+// Internes Hilfsdokument für Metadaten
+internal class SyncMeta
+{
+    public string Id { get; set; } = "";
+    public long Value { get; set; }
+    public DateTime? Timestamp { get; set; }
+}