MauMau-Server/Room/Room.cs

using System.Net.WebSockets;
using System.Text.Json;
using System.Text.RegularExpressions;
using MauMau_Server.Mau;

namespace MauMau_Server.Websockets;

public class Room
{
    private readonly IRoomManager _roomManager;
    private readonly string _roomId;
    private readonly List<ConnectionInstance> _connections = new();
    private ConnectionInstance? _host;
    private readonly Chat _chat;
    private Game? _game;
    private RoomState _state = RoomState.LOBBY;

    public Room(IRoomManager roomManager, string roomId)
    {
        _roomManager = roomManager;
        _chat = new Chat(this);
        _roomId = roomId;
    }

    public async Task InstantiateConnection(WebSocket socket, string name)
    {
        var connection = AddConnection(socket, name);
        _game?.AddPlayerToGame(connection);
        await HandleConnection(connection);
    }

    private async Task HandleConnection(ConnectionInstance connection)
    {
        BroadcastState();
        var webSocketResponse = await WebsocketManager.ReceiveAsync(connection.Socket);
        while (!webSocketResponse.Result!.CloseStatus.HasValue)
        {
            var message = JsonSerializer.Deserialize<MessageDTO>(webSocketResponse.SlicedBuffer);
            switch (message.Type)
            {
                case "GAME":
                {
                    if (_state != RoomState.GAME) break;
                    var gameInput = JsonSerializer.Deserialize<ActionDTO>(message.Payload);
                    _game.HandleAction(connection.ConnectionId, gameInput);
                    break;
                }
                case "CHAT":
                {
                    var cleanedMessage = StripHTML(message.Payload);
                    if (string.IsNullOrWhiteSpace(cleanedMessage))
                    {
                        cleanedMessage = "Mau!";
                    };
                    _chat.SendChatMessage(connection, cleanedMessage);
                    break;
                }
                case "LOBBY":
                {
                    if (connection.ConnectionId == _host?.ConnectionId)
                    {
                        ChangeLobbyState(RoomState.GAME);
                    }
                    break;
                }
            }

            BroadcastState();
            webSocketResponse = await WebsocketManager.ReceiveAsync(connection.Socket);
        }
        WebsocketManager.CloseAsync(connection.Socket, webSocketResponse.Result);
        HandleDisconnect(connection.ConnectionId);
    }

    private ConnectionInstance AddConnection(WebSocket socket, string name)
    {
        var connectionId = Guid.NewGuid().ToString();
        var connection = new ConnectionInstance(name, connectionId, socket);
        if (IsEmpty()) _host = connection;
        _connections.Add(connection);
        return connection;
    }

    private void RemoveConnection(string socketId)
    {
        _connections.RemoveAll(connection => connection.ConnectionId == socketId);
    }

    private void BroadcastGameState()
    {
        if (_game == null)
        {
            return;
        }
        foreach (var connection in _connections)
        {
            var gameState = new GameState(_game, connection.ConnectionId);
            var message = new MessageDTO("GAME", JsonSerializer.Serialize(gameState));
            WebsocketManager.SendAsync(connection.Socket, JsonSerializer.Serialize(message));
        }
    }

    private void BroadcastState()
    {
        switch (_state)
        {
            case RoomState.LOBBY:
                var message = new MessageDTO("LOBBY", JsonSerializer.Serialize("a"));
                WebsocketManager.BroadcastAsync(GetWebsockets(), JsonSerializer.Serialize(message));
                break;
            case RoomState.GAME:
                BroadcastGameState();
                break;
            default:
                //
                break;
        }
    }

    private void ChangeLobbyState(RoomState targetState)
    {
        switch (targetState)
        {
            case RoomState.LOBBY:
                _state = RoomState.LOBBY;
                _game = null;
                break;
            case RoomState.GAME:
            {
                _state = RoomState.GAME;
                _game = new Game(this);
                foreach (var connectionInstance in _connections)
                {
                    _game.AddPlayerToGame(connectionInstance);
                }
                break;
            }
            default:
                throw new ArgumentOutOfRangeException(nameof(targetState), targetState, null);
        }
    }

    private void HandleDisconnect(string socketId)
    {
        RemoveConnection(socketId);
        _game?.RemovePlayer(socketId);
        if (IsEmpty())
        {
            _roomManager.RemoveRoom(_roomId);
        }
        else if (socketId == _host.ConnectionId)
        {
            _host = _connections.First();
        }
    }

    public List<WebSocket> GetWebsockets()
    {
        return _connections.Select(connection => connection.Socket).ToList();
    }

    public bool IsEmpty()
    {
        return _connections.Count == 0;
    }
    
    private static string StripHTML(string input)
    {
        return Regex.Replace(input, "<.*?>", string.Empty);
    }

    public void EndGame(Player player)
    {
        var message = new MessageDTO("END", JsonSerializer.Serialize(new PlayerDTO(player)));
        WebsocketManager.BroadcastAsync(GetWebsockets(), JsonSerializer.Serialize(message));
        ChangeLobbyState(RoomState.LOBBY);
    }
}

public enum RoomState
{
    LOBBY,
    GAME
}