Lobby: include HostUserId in GameStateDto and let client derive host status; update tests

SlipItIn.Server.Tests/GameHubTests.cs

@@ -108,6 +108,7 @@ public class GameHubTests
         {
             GameId = game.Id,
             LobbyCode = game.LobbyCode,
+            HostUserId = game.HostId,
             Players = [new PlayerInfoDto { Username = user.Username }]
         });
 
@@ -151,7 +152,7 @@ public class GameHubTests
 
         var game = new Game { Id = 3, LobbyCode = "JOIN42", HostId = 99 };
         _gameService.Setup(s => s.JoinGameAsync("JOIN42", user.Id, ConnectionId)).ReturnsAsync(game);
-        _gameService.Setup(s => s.GetGameStateAsync(game.Id)).ReturnsAsync(new GameStateDto { GameId = 3 });
+        _gameService.Setup(s => s.GetGameStateAsync(game.Id)).ReturnsAsync(new GameStateDto { GameId = 3, HostUserId = 99 });
 
         await _hub.JoinLobby("JOIN42");
 
@@ -205,7 +206,7 @@ public class GameHubTests
 
         _gameService.Setup(s => s.SetPlayerReadyAsync(game.Id, player.Id))
             .ReturnsAsync(new Game { Id = game.Id, LobbyCode = game.LobbyCode });
-        _gameService.Setup(s => s.GetGameStateAsync(game.Id)).ReturnsAsync(new GameStateDto { GameId = game.Id });
+        _gameService.Setup(s => s.GetGameStateAsync(game.Id)).ReturnsAsync(new GameStateDto { GameId = game.Id, HostUserId = game.HostId });
 
         await _hub.PlayerReady(game.Id, player.Id);
 
@@ -540,7 +541,9 @@ public class GameHubTests
         SeedGameWithPlayers((user, ConnectionId));
         var gameId = db.Games.Single().Id;
 
-        _gameService.Setup(s => s.GetGameStateAsync(gameId)).ReturnsAsync(new GameStateDto { GameId = gameId });
+        var hostId = db.Games.Single().HostId;
+
+        _gameService.Setup(s => s.GetGameStateAsync(gameId)).ReturnsAsync(new GameStateDto { GameId = gameId, HostUserId = hostId });
 
         await _hub.RequestGameState(gameId);
 

SlipItIn.Server.Tests/GameServiceTests.cs

@@ -40,6 +40,18 @@ public class GameServiceTests
         await Assert.ThrowsAsync<InvalidOperationException>(() => _sut.CreateGameAsync(999));
     }
 
+    [Fact]
+    public async Task GetGameStateAsync_IncludesHostUserId()
+    {
+        using var db = _factory.CreateDbContext();
+        var host = TestDbHelper.SeedUser(db);
+        var (game, _) = TestDbHelper.SeedGame(db, host);
+
+        var dto = await _sut.GetGameStateAsync(game.Id);
+
+        Assert.Equal(game.HostId, dto.HostUserId);
+    }
+
     // ---------- JoinGameAsync ----------
 
     [Fact]

SlipItIn.Server/Services/GameService.cs

@@ -293,6 +293,7 @@ public class GameService : IGameService
             LobbyCode = game.LobbyCode,
             Status = game.Status.ToString(),
             Players = playerInfos,
+            HostUserId = game.HostId,
             CurrentRound = currentRound?.RoundNumber ?? 0,
             RoundTimeRemaining = roundTimeRemaining
         };

SlipItIn.Shared/DTOs/GameStateDto.cs

@@ -6,6 +6,8 @@ public class GameStateDto
     public string LobbyCode { get; set; } = string.Empty;
     public string Status { get; set; } = string.Empty;
     public List<PlayerInfoDto> Players { get; set; } = [];
+    // Host user id to let clients determine whether the current user is the host
+    public int HostUserId { get; set; }
     public int CurrentRound { get; set; }
     public int RoundTimeRemaining { get; set; }
 }

SlipItIn/ViewModels/LobbyViewModel.cs

@@ -144,8 +144,14 @@ public partial class LobbyViewModel : BaseViewModel,
                 Players.Add(player);
 
             var currentUsername = _authSession.CurrentUser?.Username;
+            var currentUserId = _authSession.CurrentUser?.UserId ?? 0;
+
             IsCurrentPlayerReady = message.Value.Players.Any(p =>
                 p.IsReady && string.Equals(p.Username, currentUsername, StringComparison.OrdinalIgnoreCase));
+
+            // Determine whether the current user is the host based on server-provided HostUserId
+            IsHost = currentUserId > 0 && message.Value.HostUserId > 0 && currentUserId == message.Value.HostUserId;
+
             CanStartGame = message.Value.Players.Count >= 2 && message.Value.Players.All(p => p.IsReady);
         });
     }