fixed stroke generation (#32)

src/DrawTogether.Actors/Drawings/DrawingSessionActor.cs

@@ -48,7 +48,7 @@ private PublishActivity()
 
     public DrawingSessionActor(string sessionId, IRequiredActor<AllDrawingsPublisherActor> drawingActivityPublisher)
     {
-        PersistenceId = sessionId;
+        PersistenceId = $"drawsession-{sessionId}";
         _drawingActivityPublisher = drawingActivityPublisher.ActorRef;
         State = new DrawingSessionState(new DrawingSessionId(sessionId));
     }

src/DrawTogether.Actors/Local/LocalDrawingSessionActor.cs

@@ -4,10 +4,12 @@
 using Akka.Hosting;
 using Akka.Streams;
 using Akka.Streams.Dsl;
+using Akka.Util;
 using DrawTogether.Actors.Drawings;
 using DrawTogether.Entities;
 using DrawTogether.Entities.Drawings;
 using DrawTogether.Entities.Drawings.Messages;
+using DrawTogether.Entities.Users;
 using static DrawTogether.Actors.Local.LocalPaintProtocol;
 
 namespace DrawTogether.Actors.Local;
@@ -93,7 +95,7 @@ protected override void OnReceive(object message)
     {
         switch (message)
         {
-            case AddPointToConnectedStroke or CreateConnectedStroke:
+            case AddPointToConnectedStroke:
                 _debouncer.Tell(message);
                 break;
             case IPaintSessionMessage paintMessage:
@@ -140,30 +142,36 @@ protected override void OnReceive(object message)
                 break;
         }
     }
+
+    private readonly int _randomSeed = Random.Shared.Next();
+    private int _strokeIdCounter = 0;
 
-    private List<IDrawingSessionCommand> TransmitActions(IReadOnlyList<IPaintSessionMessage> actions)
+    private int NextStrokeId(UserId userId)
     {
-        var createActions = actions.Where(a => a is CreateConnectedStroke)
-            .Select(a => ((CreateConnectedStroke)a).ConnectedStroke)
-            .ToArray();
-
-        var addActions = actions.OfType<AddPointToConnectedStroke>().ToArray();
+        return MurmurHash.StringHash(userId.IdentityName) + _randomSeed + _strokeIdCounter++;
+    }
+
+    private List<IDrawingSessionCommand> TransmitActions(IReadOnlyList<AddPointToConnectedStroke> actions)
+    {
+
+        // group all the actions by user
+        var userActions = actions.GroupBy(a => a.UserId).ToList();
 
-        _log.Info("BATCHED {0} create actions and {1} add actions", createActions.Length, addActions.Length);
+        _log.Info("BATCHED {0} create actions from {1} users", actions.Count, userActions.Count);
 
         var drawSessionCommands = new List<IDrawingSessionCommand>();
 
-        foreach (var create in createActions)
+        foreach (var userStuff in userActions)
         {
-            var allPoints = create.Points.ToList();
-
-            foreach (var a in addActions.Where(a => a.StrokeId == create.Id))
+            var userId = userStuff.Key;
+            var connectedStroke = new ConnectedStroke(new StrokeId(NextStrokeId(userId)))
             {
-                allPoints.Add(a.Point);
-            }
-
-            drawSessionCommands.Add(new DrawingSessionCommands.AddStroke(_drawingSessionId,
-                create with { Points = allPoints }));
+                Points = userStuff.Select(a => a.Point).ToList(),
+                StrokeColor = userStuff.First().StrokeColor,
+                StrokeWidth = userStuff.First().StrokeWidth
+            };
+
+            drawSessionCommands.Add(new DrawingSessionCommands.AddStroke(_drawingSessionId, connectedStroke));
         }
 
         return drawSessionCommands;
@@ -177,11 +185,11 @@ protected override void PreStart()
         AttemptToSubscribe();
 
         Context.SetReceiveTimeout(TimeSpan.FromMinutes(2));
-        var (sourceRef, source) = Source.ActorRef<IPaintSessionMessage>(1000, OverflowStrategy.DropHead)
+        var (sourceRef, source) = Source.ActorRef<AddPointToConnectedStroke>(1000, OverflowStrategy.DropHead)
             .PreMaterialize(_materializer);
 
         _debouncer = sourceRef;
-        source.GroupedWithin(100, TimeSpan.FromMilliseconds(75))
+        source.GroupedWithin(10, TimeSpan.FromMilliseconds(75))
             .Select(c => TransmitActions(c.ToList()))
             .SelectMany(c => c)
             .SelectAsync(1, async c =>

src/DrawTogether.Actors/Local/LocalPaintProtocol.cs

@@ -1,4 +1,5 @@
-using DrawTogether.Entities.Drawings;
+using DrawTogether.Entities;
+using DrawTogether.Entities.Drawings;
 using DrawTogether.Entities.Drawings.Messages;
 using DrawTogether.Entities.Users;
 
@@ -28,25 +29,17 @@ public sealed class LeavePaintSession(DrawingSessionId drawingSessionId, UserId
 
     public sealed class AddPointToConnectedStroke(
         Point point,
-        StrokeId strokeId,
         DrawingSessionId drawingSessionId,
-        UserId userId)
+        UserId userId, GreaterThanZeroInteger strokeWidth, Color strokeColor)
         : IPaintSessionMessage
     {
         public Point Point { get; } = point;
-
-        public StrokeId StrokeId { get; } = strokeId;
-        public DrawingSessionId DrawingSessionId { get; } = drawingSessionId;
-        public UserId UserId { get; } = userId;
-    }
-
-    public sealed class CreateConnectedStroke(DrawingSessionId drawingSessionId, UserId userId, ConnectedStroke connectedStroke)
-        : IPaintSessionMessage
-    {
-        public StrokeId StrokeId { get; } = connectedStroke.Id;
 
-        public ConnectedStroke ConnectedStroke { get; } = connectedStroke;
         public DrawingSessionId DrawingSessionId { get; } = drawingSessionId;
         public UserId UserId { get; } = userId;
+
+        public GreaterThanZeroInteger StrokeWidth { get; } = strokeWidth;
+
+        public Color StrokeColor { get; } = strokeColor;
     }
 }

src/DrawTogether/Components/Pages/Home.razor

@@ -78,21 +78,24 @@ else
     // create subscription
     async Task RunSubscription()
     {
-        var source = Source.ActorRef<DrawingActivityUpdate>(100, OverflowStrategy.DropHead);
+        var source = Source.ActorRef<List<DrawingActivityUpdate>>(100, OverflowStrategy.DropHead);
         var (srcActor, src) = source.PreMaterialize(ActorSystem);
 
         // starts the pump
         allDrawingsActor.Tell(new DrawingIndexQueries.SubscribeToDrawingSessionUpdates(srcActor));
 
-        await foreach (var item in src.RunAsAsyncEnumerable(ActorSystem).WithCancellation(_shutdownCts.Token))
+        await foreach (var items in src.RunAsAsyncEnumerable(ActorSystem).WithCancellation(_shutdownCts.Token))
         {
-            if (item.IsRemoved)
+            foreach (var item in items)
             {
-                _drawingActivities.Remove(item.DrawingSessionId);
-            }
-            else
-            {
-                _drawingActivities[item.DrawingSessionId] = item;
+                if (item.IsRemoved)
+                {
+                    _drawingActivities.Remove(item.DrawingSessionId);
+                }
+                else
+                {
+                    _drawingActivities[item.DrawingSessionId] = item;
+                }
             }
 
             StateHasChanged();

src/DrawTogether/Components/Pages/Paint.razor

@@ -75,7 +75,6 @@
         var authstate = await GetAuthenticationStateAsync.GetAuthenticationStateAsync();
         _user = authstate.User;
         _currentUserId = new UserId(_user.FindFirstValue(ClaimTypes.NameIdentifier) ?? throw new InvalidOperationException("User not authenticated"));
-        _hashedUserId = MurmurHash.StringHash(_currentUserId.IdentityName);
         DrawingSessionId = new DrawingSessionId(SessionId);
 
 
@@ -159,29 +158,8 @@
     private string mousePointerMessage = "foo";
     private string blazorHubDebugMessage = "bar";
 
-    private readonly int _randomSeed = Random.Shared.Next();
-    private int _strokeIdCounter = 0;
-    private int _hashedUserId;
-
-    private int NextStrokeId()
-    {
-        return _hashedUserId + _randomSeed + _strokeIdCounter++;
-    }
-
-    private StrokeId CurrentStrokeId { get; set; }
-
     private void CursorDown(MouseEventArgs e)
     {
-        CurrentStrokeId = new StrokeId(NextStrokeId());
-        var newStroke = new ConnectedStroke(CurrentStrokeId)
-        {
-            StrokeColor = _color,
-            StrokeWidth = _cursorSize,
-            Points = new List<Point> { new(e.OffsetX, e.OffsetY) }
-        };
-
-        _localActorHandle.Tell(new LocalPaintProtocol.CreateConnectedStroke(DrawingSessionId, _currentUserId, newStroke));
-
         if (e.Buttons == 1)
         {
             OnNext(new Point(e.OffsetX, e.OffsetY));
@@ -190,7 +168,7 @@
 
     private void OnNext(Point point)
     {
-        _localActorHandle.Tell(new LocalPaintProtocol.AddPointToConnectedStroke(point, CurrentStrokeId, DrawingSessionId, _currentUserId));
+        _localActorHandle.Tell(new LocalPaintProtocol.AddPointToConnectedStroke(point, DrawingSessionId!, _currentUserId!, _cursorSize, _color));
     }
 
     private void CursorMove(MouseEventArgs e)