безопасная обертка IsUserInvisibleAsync

backend/src/Modules/Conversations/Infrastructure/SignalR/ChatHub.cs

@@ -102,7 +102,11 @@ public sealed class ChatHub : Hub
             var isInvisible = await IsUserInvisibleAsync(_userContext.UserId, Context.ConnectionAborted);
             if (!isInvisible)
             {
-                await BroadcastPresenceToVisibleUsersAsync("user_online", new { userId }, _userContext.UserId);
+                await BroadcastPresenceToVisibleUsersAsync(
+                    "user_online",
+                    new { userId },
+                    _userContext.UserId,
+                    Context.ConnectionAborted);
             }
         }
         await base.OnConnectedAsync();
@@ -119,13 +123,22 @@ public sealed class ChatHub : Hub
                 if (set.Count == 0)
                 {
                     _userConnections.TryRemove(userId, out _);
-                    var isInvisible = await IsUserInvisibleAsync(_userContext.UserId, Context.ConnectionAborted);
+                    try
+                    {
+                        // Connection is tearing down: ConnectionAborted is already signaled and will cancel I/O.
+                        var isInvisible = await IsUserInvisibleAsync(_userContext.UserId, CancellationToken.None);
                         if (!isInvisible)
                         {
                             await BroadcastPresenceToVisibleUsersAsync(
                                 "user_offline",
                                 new { userId, lastSeen = DateTime.UtcNow },
-                            _userContext.UserId);
+                                _userContext.UserId,
+                                CancellationToken.None);
+                        }
+                    }
+                    catch (Exception ex)
+                    {
+                        _logger.LogWarning(ex, "Presence broadcast on disconnect failed for {UserId}", userId);
                     }
                 }
             }
@@ -141,7 +154,11 @@ public sealed class ChatHub : Hub
         return profile?.IsInvisible ?? false;
     }
 
-    private async Task BroadcastPresenceToVisibleUsersAsync(string eventName, object payload, Guid sourceUserId)
+    private async Task BroadcastPresenceToVisibleUsersAsync(
+        string eventName,
+        object payload,
+        Guid sourceUserId,
+        CancellationToken cancellationToken)
     {
         var recipients = _userConnections.Keys
             .Where(id => id != sourceUserId.ToString())
@@ -153,7 +170,7 @@ public sealed class ChatHub : Hub
         if (recipients.Count == 0)
             return;
 
-        var recipientProfiles = await _profileRepository.GetAsync(recipients, Context.ConnectionAborted);
+        var recipientProfiles = await _profileRepository.GetAsync(recipients, cancellationToken);
         var invisibleRecipientIds = recipientProfiles
             .Where(p => p.IsInvisible)
             .Select(p => p.UserId)

client-web/src/modules/chats/application/chatStore.ts

@@ -125,7 +125,11 @@ export const useChatStore = create<ChatState>((set, get) => ({
 
       set({ isLoadingMessages: true });
       const currentMessages = state.messages[chatId] || [];
-      const cursor = !reset && currentMessages.length > 0 ? currentMessages[0].sequenceId.toString() : undefined;
+      const firstSeq = currentMessages[0]?.sequenceId;
+      const cursor =
+        !reset && currentMessages.length > 0 && firstSeq != null
+          ? String(firstSeq)
+          : undefined;
       
       const fetched = await ChatApi.getMessages(chatId, cursor);