Show waiting players during practice

game.js

@@ -35,6 +35,8 @@ let roomId = "";
 let gameMode = "practice";
 let multiplayerState = "local";
 let botTimer = 0;
+let lobbyTimer = 0;
+let waitingPlayers = 0;
 
 function createBoard() {
   return Array.from({ length: size }, () => Array(size).fill(empty));
@@ -54,6 +56,7 @@ function setupGame() {
 
 function connectToServer() {
   gameMode = "online";
+  stopLobbyPolling();
   closeSocket();
   localPlayer = "";
   roomId = "";
@@ -103,7 +106,8 @@ function startPracticeMode() {
   roomId = "";
   multiplayerState = "local";
   setupGame();
-  setMultiplayerState("local", "BOT practice. You are X. Random O replies after each move.");
+  setPracticeStatus("BOT practice. You are X. Random O replies after each move.");
+  startLobbyPolling();
   updateModeButtons();
 }
 
@@ -115,6 +119,40 @@ function closeSocket() {
   socket = null;
 }
 
+function startLobbyPolling() {
+  stopLobbyPolling();
+  checkLobby();
+  lobbyTimer = window.setInterval(checkLobby, 3000);
+}
+
+function stopLobbyPolling() {
+  if (lobbyTimer) {
+    window.clearInterval(lobbyTimer);
+    lobbyTimer = 0;
+  }
+}
+
+async function checkLobby() {
+  if (gameMode !== "practice") {
+    return;
+  }
+
+  try {
+    const response = await fetch("/lobby", { cache: "no-store" });
+    if (!response.ok) {
+      return;
+    }
+
+    const status = await response.json();
+    waitingPlayers = Number(status.waitingPlayers || 0);
+    if (!gameOver && currentPlayer === localPlayer) {
+      setPracticeStatus("BOT practice. You are X. Random O replies after each move.");
+    }
+  } catch {
+    waitingPlayers = 0;
+  }
+}
+
 function handleServerMessage(payload) {
   if (payload.type === "waiting") {
     localPlayer = "";
@@ -255,7 +293,7 @@ function playLocalMove(row, col) {
   }
 
   if (!gameOver) {
-    setMultiplayerState("local", "Bot thinking...");
+    setPracticeStatus("Bot thinking...");
     botTimer = window.setTimeout(playBotMove, 360);
   }
 }
@@ -276,14 +314,14 @@ function applyMove(row, col, player, source) {
   if (win.length > 0) {
     winningCells = win;
     gameOver = true;
-    setMultiplayerState(activeState(), `${player} wins with four in a row.`);
+    setActiveStatus(`${player} wins with four in a row.`);
     render();
     return true;
   }
 
   if (isDraw()) {
     gameOver = true;
-    setMultiplayerState(activeState(), "Draw. The board is full.");
+    setActiveStatus("Draw. The board is full.");
     render();
     return true;
   }
@@ -291,7 +329,7 @@ function applyMove(row, col, player, source) {
   currentPlayer = opponentOf(player);
   const captureMessage = captured.length > 0 ? `${player} captured ${captured.length}. ` : "";
   const turnMessage = currentPlayer === localPlayer ? "Your turn." : waitingMessage();
-  setMultiplayerState(activeState(), `${captureMessage}${turnMessage}`);
+  setActiveStatus(`${captureMessage}${turnMessage}`);
   render();
   flashCapturedCells(captured);
 
@@ -306,6 +344,15 @@ function activeState() {
   return gameMode === "practice" ? "local" : "paired";
 }
 
+function setActiveStatus(text) {
+  if (gameMode === "practice") {
+    setPracticeStatus(text);
+    return;
+  }
+
+  setMultiplayerState(activeState(), text);
+}
+
 function waitingMessage() {
   return gameMode === "practice" ? "Bot turn." : `Waiting for ${currentPlayer}.`;
 }
@@ -401,6 +448,11 @@ function setMultiplayerState(state, text) {
   messageElement.textContent = text;
 }
 
+function setPracticeStatus(text) {
+  const suffix = waitingPlayers > 0 ? " NET: player waiting." : " NET: no one waiting.";
+  setMultiplayerState("local", `${text}${suffix}`);
+}
+
 function playBotMove() {
   if (gameMode !== "practice" || gameOver || currentPlayer !== "O") {
     return;
@@ -471,7 +523,7 @@ resetButton.addEventListener("click", () => {
   setupGame();
 
   if (gameMode === "practice") {
-    setMultiplayerState("local", "BOT practice. You are X. Random O replies after each move.");
+    setPracticeStatus("BOT practice. You are X. Random O replies after each move.");
     return;
   }
 
@@ -482,6 +534,7 @@ resetButton.addEventListener("click", () => {
 practiceButton.addEventListener("click", startPracticeMode);
 onlineButton.addEventListener("click", () => {
   gameMode = "online";
+  stopLobbyPolling();
   localPlayer = "";
   roomId = "";
   multiplayerState = "connecting";

index.html

@@ -58,7 +58,7 @@
 
         <div class="rule-card">
           <h2>MODES</h2>
-          <p>BOT is local practice against random moves. NET pairs the first two connected players automatically.</p>
+          <p>BOT is local practice against random moves and shows if NET has a player waiting. NET pairs the first two connected players automatically.</p>
         </div>
 
         <ol id="moveList" class="move-list" aria-label="Move history"></ol>

server.js

@@ -76,6 +76,15 @@ const server = http.createServer((request, response) => {
     return;
   }
 
+  if (requestUrl.pathname === "/lobby") {
+    response.writeHead(200, {
+      "Cache-Control": "no-store",
+      "Content-Type": "application/json; charset=utf-8",
+    });
+    response.end(request.method === "HEAD" ? undefined : JSON.stringify(lobbyStatus()));
+    return;
+  }
+
   const staticName = staticFiles.get(requestUrl.pathname);
   if (!staticName) {
     response.writeHead(404);
@@ -257,6 +266,13 @@ function pairClients(xClient, oClient) {
   send(oClient, { type: "paired", player: "O", roomId });
 }
 
+function lobbyStatus() {
+  return {
+    activeGames: rooms.size,
+    waitingPlayers: waitingClientId && clients.has(waitingClientId) ? 1 : 0,
+  };
+}
+
 function handleSocketData(client, buffer) {
   if (!clients.has(client.id)) {
     return;