refactor: save current workspace state including FinlyticAnalyzer fixes, FinlyticApp trade route alignment, and DTO audit documentation

FinlyticBackend/Hubs/FavoritesPriceHub.cs

@@ -1,5 +1,7 @@
 using System;
+using System.Collections.Concurrent;
 using System.Threading.Tasks;
+using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.SignalR;
 using Microsoft.Extensions.Logging;
 
@@ -8,24 +10,71 @@ namespace FinlyticBackend.Hubs;
 /// <summary>
 /// SignalR Hub streaming real-time stock prices & daily % growth updates for favorite assets every 10 seconds.
 /// </summary>
+[Authorize]
 public class FavoritesPriceHub : Hub
 {
     private readonly ILogger<FavoritesPriceHub> _logger;
 
+    // Speichert thread-sicher, wie viele aktive Verbindungen ein User hat (UserId -> ConnectionCount)
+    private static readonly ConcurrentDictionary<string, int> ActiveUserConnections = new();
+
     public FavoritesPriceHub(ILogger<FavoritesPriceHub> logger)
     {
         _logger = logger;
     }
 
+    /// <summary>
+    /// Liefert eine Übersicht aller aktuell mit dem Hub verbundenen User-IDs.
+    /// </summary>
+    public static string[] GetActiveUserIds() => [.. ActiveUserConnections.Keys];
+
     public override async Task OnConnectedAsync()
     {
-        _logger.LogInformation("[FavoritesPriceHub] SignalR client connected: ConnectionId={ConnectionId}", Context.ConnectionId);
+        var userId = Context.UserIdentifier;
+
+        if (!string.IsNullOrEmpty(userId))
+        {
+            // Füge die Verbindung der benutzerspezifischen Gruppe hinzu
+            await Groups.AddToGroupAsync(Context.ConnectionId, GetGroupName(userId));
+
+            ActiveUserConnections.AddOrUpdate(userId, 1, (_, count) => count + 1);
+
+            _logger.LogInformation("[FavoritesPriceHub] User '{UserId}' connected (ConnectionId={ConnectionId}). Active connections for user: {Count}",
+                userId, Context.ConnectionId, ActiveUserConnections[userId]);
+        }
+        else
+        {
+            _logger.LogWarning("[FavoritesPriceHub] Anonymous SignalR client connected without UserIdentifier: ConnectionId={ConnectionId}", Context.ConnectionId);
+        }
+
         await base.OnConnectedAsync();
     }
 
     public override async Task OnDisconnectedAsync(Exception? exception)
     {
-        _logger.LogInformation("[FavoritesPriceHub] SignalR client disconnected: ConnectionId={ConnectionId}", Context.ConnectionId);
+        var userId = Context.UserIdentifier;
+
+        if (!string.IsNullOrEmpty(userId))
+        {
+            await Groups.RemoveFromGroupAsync(Context.ConnectionId, GetGroupName(userId));
+
+            ActiveUserConnections.AddOrUpdate(userId, 0, (_, count) =>
+            {
+                var newCount = count - 1;
+                return newCount < 0 ? 0 : newCount;
+            });
+
+            // Wenn keine aktiven Verbindungen mehr bestehen, aus Dictionary entfernen
+            if (ActiveUserConnections.TryGetValue(userId, out var remainingCount) && remainingCount <= 0)
+            {
+                ActiveUserConnections.TryRemove(userId, out _);
+            }
+
+            _logger.LogInformation("[FavoritesPriceHub] User '{UserId}' disconnected (ConnectionId={ConnectionId})", userId, Context.ConnectionId);
+        }
+
         await base.OnDisconnectedAsync(exception);
     }
-}
+
+    public static string GetGroupName(string userId) => $"User_{userId.Trim()}";
+}