Added username validation

Auto hide enter/leave room
Username starts as UNNAMED now
Show roomnumber for connected room

PongGame/Hubs/PongHub.cs

@@ -21,7 +21,6 @@ public class PongHub : Hub<IPongClient> {
     public override Task OnConnectedAsync() {
         Player = Lobby.CreatePlayer();
         Player.Client = Clients.Client(Context.ConnectionId);
-        Player.Username = "Anon";
         return Task.CompletedTask;
     }
 
@@ -42,10 +41,10 @@ public class PongHub : Hub<IPongClient> {
         return Task.FromResult(room.ID);
     }
 
-    public Task<string> JoinRoom(string roomId) {
+    public async Task<string> JoinRoom(string roomId) {
         AssertNotInRoom();
-        var room = Lobby.JoinRoom(Player, roomId);
+        var room = await Lobby.JoinRoom(Player, roomId);
-        return Task.FromResult(room.ID);
+        return room.ID;
     }
 
     public Task MovePaddle(int dir) {
@@ -53,21 +52,14 @@ public class PongHub : Hub<IPongClient> {
         var direction = (PongPaddleDirection)dir;
         if (!Enum.IsDefined(direction))
             throw new HubException($"Invalid direction: {dir}!");
-        room.MovePaddle(Player, direction);
+        return room.MovePaddle(Player, direction);
-        return Task.CompletedTask;
     }
 
-    public Task LeaveRoom() {
+    public Task LeaveRoom()
-        Lobby.LeaveRoom(Player);
+        => Lobby.LeaveRoom(Player);
-        return Task.CompletedTask;
-    }
 
-    public Task RequestUsernameChange(string username) {
+    public Task RequestUsernameChange(string username)
-        // TOOD: check this
+        => Lobby.ChangeUsername(Player, username);
-        Logger.LogInformation("Player {Player} requested username change to [{username}]", Player, username);
-        Player.Username = username;
-        return Task.CompletedTask;
-    }
 
     public override Task OnDisconnectedAsync(Exception? exception) {
         Lobby.RemovePlayer(Player);

PongGame/Hubs/PongLobbyCollection.cs

@@ -1,4 +1,6 @@
-using Microsoft.AspNetCore.SignalR;
+using System.Numerics;
+using System.Text.RegularExpressions;
+using Microsoft.AspNetCore.SignalR;
 
 namespace PongGame.Hubs;
 
@@ -35,19 +37,24 @@ public class PongLobby {
         return room;
     }
 
-    public PongRoom JoinRoom(PongPlayer player, string roomId) {
+    public Task<PongRoom> JoinRoom(PongPlayer player, string roomId) {
         PongRoom? room;
         lock (PongRooms) {
             room = PongRooms.GetValueOrDefault(roomId);
         }
         if (room is null) throw new HubException($"Room [{roomId}] not found!");
         room.Join(player);
-        return room;
+        return Task.FromResult(room);
     }
 
-    public void LeaveRoom(PongPlayer player) {
+    public Task LeaveRoom(PongPlayer player) {
-        if (player.ConnectedRoom is PongRoom room)
+        if (player.ConnectedRoom is PongRoom room) {
             room.Leave(player);
+            if (room.IsEmpty)
+                lock (PongRooms)
+                    _ = PongRooms.Remove(room.ID);
+        }
+        return Task.CompletedTask;
     }
 
     private readonly Random random = new();
@@ -61,4 +68,28 @@ public class PongLobby {
         } while (PongRooms.ContainsKey(id));
         return id;
     }
+
+    public async Task ChangeUsername(PongPlayer player, string username) {
+        username = ValidateUsername(username);
+        if (player.Username == username) {
+            await player.Client.UsernameChanged(username);
+            return;
+        }
+        lock (connectedPlayers) {
+            // TODO: separate hashset for usernames
+            if (connectedPlayers.Select(i => i.Username).Contains(username))
+                throw new HubException($"Username {username} is already taken!");
+        }
+        Logger.LogInformation("Player {Player} requested username change to [{username}]", player, username);
+        player.Username = username;
+    }
+
+    private static readonly Regex UsernameRegex = new(@"^(?!.*[._ -]{2})[\w._ -]{3,20}$", RegexOptions.Compiled, TimeSpan.FromMilliseconds(200));
+
+    private static string ValidateUsername(string username) {
+        username = username.Trim();
+        if (!UsernameRegex.IsMatch(username))
+            throw new HubException($"At most 20 characters, no two consecutive symbols");
+        return username;
+    }
 }

PongGame/Hubs/PongPlayer.cs

@@ -4,7 +4,7 @@ namespace PongGame.Hubs;
 
 [DebuggerDisplay($"{{{nameof(ToString)}(),nq}}")]
 public class PongPlayer {
-    private string username = default!;
+    private string username = "UNNAMED";
 
     public PongRoom? ConnectedRoom { get; internal set; }
     public string Username {

PongGame/Hubs/PongRoom.cs

@@ -18,6 +18,8 @@ public class PongRoom {
 
     public PongPlayer? Player1 { get; private set; }
     public PongPlayer? Player2 { get; private set; }
+    public bool IsEmpty => Player1 is null && Player2 is null;
+
     private PongGameState State = PongGameState.Initial;
 
     public void Join(PongPlayer player) {
@@ -67,7 +69,7 @@ public class PongRoom {
         if (Player1 is PongPlayer player1 && Player2 is PongPlayer player2) {
             Logger.LogInformation("[{ID}] Pong game started: {player1} vs. {player2}", ID, player1, player2);
             ResumeGame();
-        } else if (Player1 is null && Player2 is null) {
+        } else if (IsEmpty) {
             CloseRoom();
         } else
             PauseGame();
@@ -84,16 +86,15 @@ public class PongRoom {
 
     public override string ToString() => $"[{ID}]";
 
-    public void MovePaddle(PongPlayer player, PongPaddleDirection direction) {
+    public Task MovePaddle(PongPlayer player, PongPaddleDirection direction) {
         if (Player1 == player) {
             State.Paddle1.Direction = direction;
             Logger.LogDebug(DIRECTION_LOG_TEMPLATE, ID, 1, player, direction);
-            return;
         } else if (Player2 == player) {
             State.Paddle2.Direction = direction;
             Logger.LogDebug(DIRECTION_LOG_TEMPLATE, ID, 2, player, direction);
-            return;
+        } else
-        }
             throw new InvalidOperationException("Player is not in this room, but moved! Assumably players room wasn't deleted.");
+        return Task.CompletedTask;
     }
 }

PongGame/Pages/Pong.cshtml

@@ -8,20 +8,24 @@
   <h1 class="display-4">Pong</h1>
   <h3 id="connection">Connection Status</h3>
 
-  <button id="createlobby" class="btn btn-primary mb-3">Create</button>
+  <button id="createlobby" class="btn btn-primary mb-3">Create Room</button>
-  <button id="leavelobby" class="btn btn-primary mb-3">Leave</button>
+  <button id="leavelobby" class="btn btn-primary mb-3 d-none">Leave Room</button>
 
-  <div class="input-group mb-3">
+  <div id="joinroomdiv" class="input-group mb-3">
     <input id="roomid" type="text" class="form-control" placeholder="Room ID" aria-label="Room ID" aria-describedby="joinroom">
-    <button id="joinroom" class="btn btn-outline-secondary" type="button">Button</button>
+    <button id="joinroom" class="btn btn-outline-secondary" type="button">Join Room</button>
   </div>
 
-  <div class="input-group mb-3">
+  <div class="input-group mb-3 has-validation">
     <input id="username" type="text" class="form-control" placeholder="Username" aria-label="Username" aria-describedby="setusername">
     <button id="setusername" class="btn btn-outline-secondary" type="button">Set Username</button>
+    <div id="usernameerror" class="invalid-feedback"></div>
   </div>
 
+  <div>
+    <h4>Room <span id="connectedroomid"></span></h4>
     <div id="canvas-container" class="mb-3"></div>
+  </div>
 </div>
 
 <script src="~/lib/signalr/dist/browser/signalr.min.js"></script>

PongGame/wwwroot/js/pong.js

@@ -11,26 +11,29 @@ function getElement(id) {
 }
 
 const connectionStatus = getElement("connection");
-const createlobby = getElement("createlobby");
+const createroom = getElement("createlobby");
 const roomidinput = getElement("roomid");
 const joinroom = getElement("joinroom");
+const joinroomdiv = getElement("joinroomdiv");
 const usernameinput = getElement("username");
 const setusername = getElement("setusername");
-const leavelobby = getElement("leavelobby");
+const leaveroom = getElement("leavelobby");
+const usernameerror = getElement("usernameerror");
+const connectedroomid = getElement("connectedroomid");
 
-connection.onclose(function (error) {
+connection.onclose(function (err) {
-  if (error) {
+  if (err) {
     connectionStatus.textContent = "Unexpected error!";
-    return console.error(`Connection aborted: ${error.message}`);
+    return console.error(`Connection aborted: ${err.message}`);
   }
   console.info("Disconnected!");
   connectionStatus.textContent = "Closed!";
 });
 
-connection.onreconnecting(function (error) {
+connection.onreconnecting(function (err) {
-  if (error) {
+  if (err) {
     connectionStatus.textContent = "Reconnecting!";
-    return console.error(`Connection reconnecting: ${error.message}`);
+    return console.error(`Connection reconnecting: ${err.message}`);
   }
   console.info("Reconnecting!");
   connectionStatus.textContent = "Reconnecting!";
@@ -41,11 +44,20 @@ connection.onreconnected(function (connectionId) {
   connectionStatus.textContent = "Connected!";
 });
 
-createlobby.addEventListener("click", function (event) {
+function show(elem) { elem.classList.remove("d-none"); }
-  connection.invoke("CreateRoom").then(function (roomId) {
+function hide(elem) { elem.classList.add("d-none"); }
+
+function roomJoined(roomId) {
   roomidinput.value = roomId;
+  connectedroomid.textContent = roomId;
   console.info(`Joined room [${roomId}]`);
-  }).catch(function (err) {
+  hide(createroom);
+  hide(joinroomdiv);
+  show(leaveroom);
+}
+
+createroom.addEventListener("click", function (event) {
+  connection.invoke("CreateRoom").then(roomJoined).catch(function (err) {
     return console.error(err.toString());
   });
   event.preventDefault();
@@ -57,24 +69,44 @@ connection.on("GameStateChanged", function (state) {
 connection.on("UsernameChanged", function (username) {
   console.info(`Username is now ${username}`);
   usernameinput.value = username;
+  usernameinput.classList.remove("is-invalid");
+  usernameinput.classList.add("is-valid");
 });
 
 joinroom.addEventListener("click", function (event) {
-  connection.invoke("JoinRoom", roomidinput.value).catch(function (err) {
+  connection.invoke("JoinRoom", roomidinput.value).then(roomJoined).catch(function (err) {
     return console.error(err.toString());
   });
   event.preventDefault();
 });
 
+function hubExceptionMessage(msg) {
+  const needle = "HubException: ";
+  let idx = msg.lastIndexOf(needle);
+  if (idx < 0) return msg;
+  return msg.substr(idx + needle.length);
+}
+
+usernameinput.addEventListener("input", function (event) {
+  usernameinput.classList.remove("is-valid");
+});
+
 setusername.addEventListener("click", function (event) {
   connection.invoke("RequestUsernameChange", usernameinput.value).catch(function (err) {
+    usernameerror.textContent = hubExceptionMessage(err.message);
+    usernameinput.classList.add("is-invalid");
     return console.error(err.toString());
   });
   event.preventDefault();
 });
 
-leavelobby.addEventListener("click", function (event) {
+leaveroom.addEventListener("click", function (event) {
-  connection.invoke("LeaveRoom").catch(function (err) {
+  connection.invoke("LeaveRoom").then(function () {
+    roomidinput.value = "";
+    show(createroom);
+    show(joinroomdiv);
+    hide(leaveroom);
+  }).catch(function (err) {
     return console.error(err.toString());
   });
   event.preventDefault();
@@ -88,7 +120,7 @@ function movePaddle(direction) {
 
 // Create the application helper and add its render target to the page
 let app = new PIXI.Application({ width: 1000, height: 500 });
-getElement('canvas-container').appendChild(app.view);
+getElement("canvas-container").appendChild(app.view);
 
 let graphics = new PIXI.Graphics();
 app.stage.addChild(graphics);
@@ -163,8 +195,8 @@ const keyEvent = (function () {
   return handler;
 })();
 
-document.addEventListener('keydown', keyEvent);
+document.addEventListener("keydown", keyEvent);
-document.addEventListener('keyup', keyEvent);
+document.addEventListener("keyup", keyEvent);
 
 connection.start().then(function () {
   console.info(`Connected!`);