qtcnet-server/qtc-net-server/Hubs/ChatHub.cs

using qtc_api.Services.RoomService;
using System.Text.Json;

namespace qtc_api.Hubs
{
    public class ChatHub : Hub
    {
        private IUserService _userService;
        private IRoomService _roomService;
        private ILogger<ChatHub> _logger;
        private DataContext _dataContext;
        private ServerConfig _serverConfig;

        public static readonly Dictionary<string, List<User>> GroupUsers = [];
        public static readonly Dictionary<string, List<string>> ConnectedUsers = [];
        public static readonly List<User> OnlineUsers = [];

        private static User ServerUser = new()
        {
            Id = "0",
            Username = "Server",
        };

        public ChatHub(IUserService userService, IRoomService roomService, ILogger<ChatHub> logger, DataContext dataContext, ServerConfig serverConfig)
        {
            _userService = userService;
            _roomService = roomService;
            _logger = logger;
            _dataContext = dataContext;
            _serverConfig = serverConfig;
        }

        public async override Task OnConnectedAsync()
        {
            Log("Client Connected To Hub");

            var uid = Context.UserIdentifier;
            if (uid != null)
            {
                var user = await _userService.GetUserById(uid);
                if (user != null && user.Success && user.Data != null)
                {
                    var userId = user.Data.Id;

                    lock (ConnectedUsers)
                    {
                        if (!ConnectedUsers.TryGetValue(userId, out List<string>? value))
                        {
                            value = [];
                            ConnectedUsers[userId] = value;
                        }

                        value.Add(Context.ConnectionId);
                    }

                    if (!OnlineUsers.Any(e => e.Id == userId))
                    {
                        Log("Setting User Online...");
                        OnlineUsers.Add(user.Data);
                        if (user.Data.Status == 0) await UpdateStatusAsync(user.Data, 1);

                        await Clients.Client(Context.ConnectionId).SendAsync("RefreshRoomList");
                        await Clients.Client(Context.ConnectionId).SendAsync("ReceiveServerConfig", _serverConfig);
                    }
                }
            }
        }

        public override async Task OnDisconnectedAsync(Exception? ex)
        {
            Log("Client Disconnected From Hub");

            var uid = Context.UserIdentifier;
            if (uid != null)
            {
                var user = await _userService.GetUserById(uid);
                if (user != null && user.Success && user.Data != null)
                {
                    var userId = user.Data.Id;

                    lock (ConnectedUsers)
                    {
                        if (ConnectedUsers.TryGetValue(userId, out List<string>? value))
                        {
                            value.Remove(Context.ConnectionId);
                        }
                    }

                    if (ConnectedUsers[userId].Count == 0)
                    {
                        ConnectedUsers.Remove(userId);
                        if (OnlineUsers.Any(e => e.Id == userId))
                        {
                            // set user offline if there aren't any more connections
                            var onlineUser = OnlineUsers.FirstOrDefault(e => e.Id == userId);
                            if (onlineUser != null)
                            {
                                Log("User Has No More Connections. Setting Offline...");
                                OnlineUsers.Remove(onlineUser);
                                if (user.Data.Status >= 1)
                                    await UpdateStatusAsync(onlineUser, 0);
                            }

                            // also remove the user from any rooms
                            var room = await _roomService.GetRoom(user.Data.CurrentRoomId);
                            if (room.Data != null)
                                await LeaveRoomAsync(user.Data, room.Data);
                        }
                    }
                }
            }
        }

        [HubMethodName("UpdateStatus")]
        [Authorize]
        public async Task UpdateStatusAsync(User user, int status)
        {
            var statusDto = new UserStatusDto { Id = user.Id, Status = status };

            Log($"Updating Status\n{JsonSerializer.Serialize(statusDto)}");

            var res = await _userService.UpdateStatus(statusDto);

            if (res != null && res.Success && res.Data != null)
            {
                // send UserUpdate to all clients
                UserInformationDto userInfoDto = new();
                userInfoDto.MapToUser(user);

                await Clients.All.SendAsync("UserUpdate", userInfoDto);

                Log($"Status Was Set To {res.Data.Status} On User {user.Username}");
                await Clients.Client(Context.ConnectionId).SendAsync("UpdateCurrentUser");
            }
            else
                Log($"Something Went Wrong Setting The Status On User {user.Username}");
        }

        [HubMethodName("JoinRoom")]
        [Authorize]
        public async Task JoinRoomAsync(User user, Room room)
        {
            await Groups.AddToGroupAsync(Context.ConnectionId, room.Id);

            await Clients.Group(room.Id).SendAsync("RoomMessage", ServerUser, $"User {user.Username} Has Joined {room.Name}", room);

            if (!GroupUsers.TryGetValue(room.Id, out _)) { GroupUsers.Add(room.Id, new List<User>()); }
            GroupUsers[room.Id].Add(user);

            await Clients.Group(room.Id).SendAsync("RoomUserList", room, GroupUsers[room.Id]);
            Log($"User {user.Username} Has Joined {room.Name}");

            user.CurrentRoomId = room.Id;

            ServiceResponse<Room> dbRoomRes = await _roomService.GetRoom(room.Id);
            Room? dbRoom = dbRoomRes?.Data;

            if (dbRoom != null) dbRoom.UserCount += 1;

            await _dataContext.SaveChangesAsync();
            await Clients.All.SendAsync("RefreshRoomList");
        }

        [HubMethodName("JoinRoomGuest")]
        public async Task JoinRoomGuestAsync(string roomId, string username)
        {
            // here we can just add the client to the room group and call it a day since the user isn't authenticated
            var room = await _roomService.GetRoom(roomId);

            if (room != null && room.Success && room.Data != null)
            {
                await Groups.AddToGroupAsync(Context.ConnectionId, room.Data.Id);

                await Clients.Group(room.Data.Id).SendAsync("RoomMessage", ServerUser, $"Guest User {username} Has Joined {room.Data.Name}", room);

                room.Data.UserCount += 1;
                await _dataContext.SaveChangesAsync();

                await Clients.All.SendAsync("RefreshRoomList");
            }
        }

        [HubMethodName("LeaveRoom")]
        [Authorize]
        public async Task LeaveRoomAsync(User user, Room room)
        {
            await Groups.RemoveFromGroupAsync(Context.ConnectionId, room.Id);

            await Clients.Group(room.Id).SendAsync("RoomMessage", ServerUser, $"User {user.Username} Has Left {room.Name}", room);

            if (GroupUsers.TryGetValue(room.Id, out _)) GroupUsers[room.Id].Remove(GroupUsers[room.Id].FirstOrDefault(e => e.Id == user.Id)!);

            await Clients.Group(room.Id).SendAsync("RoomUserList", room, GroupUsers[room.Id]);
            Log($"User {user.Username} Has Left {room.Name}");

            user.CurrentRoomId = string.Empty;

            ServiceResponse<Room> dbRoomRes = await _roomService.GetRoom(room.Id);
            Room? dbRoom = dbRoomRes?.Data;

            if (dbRoom != null) dbRoom.UserCount -= 1;

            await _dataContext.SaveChangesAsync();
            await Clients.All.SendAsync("RefreshRoomList");
        }

        [HubMethodName("SendMessage")]
        [Authorize]
        public async Task SendMessageAsync(User user, Message message, Room room)
        {
            await Clients.Group(room.Id).SendAsync("RoomMessage", user, $"{message.Content}", room);
        }

        [HubMethodName("SendDirectMessage")]
        [Authorize]
        public async Task SendDirectMessageAsync(User user, UserInformationDto userToMsg, Message message)
        {
            // send direct message directly to connected user
            if (ConnectedUsers.TryGetValue(userToMsg.Id, out List<string>? value))
            {
                var connection = value.FirstOrDefault();
                if (connection != null)
                {
                    UserInformationDto userInformationDto = new UserInformationDto { Id = user.Id, Username = user.Username, Bio = user.Bio, Role = user.Role, Status = user.Status, CreatedAt = user.CreatedAt, DateOfBirth = user.DateOfBirth, ProfilePicture = user.ProfilePicture, ProfileCosmeticId = user.ActiveProfileCosmetic };
                    await Clients.Client(connection).SendAsync("ReceiveDirectMessage", message, userInformationDto);
                    return;
                }
            }
        }

        private void Log(string message) => _logger.LogInformation(message);
    }
}