fix: chess multiplayer — lobby sync, session leaks, error handling

Phase 1 fixes:
- lobby.js: guest waits 2.5s before entering game (gives host time to detect)
- challenge.js: validate match_id exists before navigating to lobby
- match-session.js: remove visibilitychange listener on destroy (memory leak fix)
- match-session.js: only fire onConnectionRestored after actual disconnection
- net.js: handle non-JSON server responses gracefully (nginx 502 pages etc)
- result.js: pass actual timeControl to rematch instead of hardcoded rapid_10_0
- Remove dead chess/logic/live.js and ludo/logic/live.js (unused)

Fixes WTF #15, #19, #23, #24, #35, #37, #54, #150
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

public/js/core/match-session.js

@@ -55,6 +55,9 @@ export function destroy() {
   clearInterval(currentSession.pollTimer);
   clearInterval(currentSession.pingTimer);
   clearInterval(currentSession.disconnectTimer);
+  if (currentSession._visibilityHandler) {
+    document.removeEventListener('visibilitychange', currentSession._visibilityHandler);
+  }
   localStorage.removeItem('el3ab_active_match');
   currentSession = null;
 }
@@ -101,8 +104,9 @@ function startPolling() {
       if (!data || data.error) return;
 
       // Connection is alive
+      const wasDisconnected = (Date.now() - currentSession.lastServerPing) > 10000;
       currentSession.lastServerPing = Date.now();
-      currentSession.onConnectionRestored?.();
+      if (wasDisconnected) currentSession.onConnectionRestored?.();
 
       // Handle server-detected abandonment
       if (data.status === 'abandoned') {
@@ -158,23 +162,20 @@ function startDisconnectWatch() {
 
 // ===== TAB VISIBILITY (handles tab switch/minimize) =====
 function setupVisibilityHandler() {
-  document.addEventListener('visibilitychange', () => {
+  const handler = () => {
     if (!currentSession) return;
 
     if (document.hidden) {
-      // Tab went to background — pause expensive operations
       currentSession.isBackground = true;
     } else {
-      // Tab came back — resume and immediately poll for updates
       currentSession.isBackground = false;
-      currentSession.lastServerPing = Date.now(); // Reset so we don't false-disconnect
+      currentSession.lastServerPing = Date.now();
 
-      // Immediately fetch latest state
       if (currentSession.onOpponentMove) {
         const endpoint = currentSession.gameType === 'ludo' ? 'ludo-match.php' : currentSession.gameType === 'domino' ? 'domino-match.php' : currentSession.gameType === 'backgammon' ? 'backgammon-match.php' : 'game.php';
         net.post(endpoint, { action: 'get', match_id: currentSession.matchId })
           .then(data => {
-            if (data && !data.error) {
+            if (data && !data.error && currentSession) {
               currentSession.onOpponentMove(data);
               markOpponentActive();
             }
@@ -182,7 +183,9 @@ function setupVisibilityHandler() {
           .catch(() => {});
       }
     }
-  });
+  };
+  currentSession._visibilityHandler = handler;
+  document.addEventListener('visibilitychange', handler);
 }
 
 // ===== UTILITY =====

public/js/core/net.js

@@ -19,7 +19,13 @@ export async function api(endpoint, options = {}) {
 
   const url = endpoint.startsWith('http') ? endpoint : `${API_BASE}/${endpoint}`;
   const res = await fetch(url, config);
-  const data = await res.json();
+  const text = await res.text();
+  let data;
+  try {
+    data = JSON.parse(text);
+  } catch (e) {
+    throw new ApiError('Server returned invalid response', res.status || 502);
+  }
 
   if (!res.ok) {
     if (res.status === 401 && !options._retried) {

public/js/modules/chess/logic/live.js

-// Chess Live Multiplayer — realtime game sync via Supabase
-import * as realtime from '../../../core/realtime.js';
-import * as net from '../../../core/net.js';
-import * as store from '../../../core/store.js';
-
-let unsubMatch = null;
-let unsubQueue = null;
-let matchId = null;
-let onMoveReceived = null;
-let onGameStateChange = null;
-let lastMoveCount = 0;
-
-export function startMatchmaking(gameKey, timeControl, callbacks) {
-  const userId = store.get('auth.userId');
-
-  unsubQueue = realtime.subscribeQueue(userId, (change) => {
-    if (change.type === 'UPDATE' && change.new?.match_id) {
-      stopMatchmaking();
-      callbacks.onMatchFound({
-        matchId: change.new.match_id,
-        color: change.new.matched_with ? 'b' : 'w',
-        opponentId: change.new.matched_with
-      });
-    }
-  });
-
-  return net.post('matchmaking.php', {
-    action: 'queue',
-    game_key: gameKey,
-    time_control: timeControl
-  });
-}
-
-export function stopMatchmaking() {
-  if (unsubQueue) { unsubQueue(); unsubQueue = null; }
-}
-
-export function joinMatch(id, callbacks) {
-  matchId = id;
-  lastMoveCount = 0;
-  onMoveReceived = callbacks.onMove;
-  onGameStateChange = callbacks.onStateChange;
-
-  realtime.connect();
-  unsubMatch = realtime.subscribeMatch(id, (change) => {
-    if (change.type === 'UPDATE' && change.new) {
-      const match = change.new;
-      if (match.move_count > lastMoveCount) {
-        lastMoveCount = match.move_count;
-        if (onMoveReceived) onMoveReceived(match);
-      }
-      if (match.status !== 'in_progress' && onGameStateChange) {
-        onGameStateChange(match);
-      }
-    }
-  });
-}
-
-export function leaveMatch() {
-  if (unsubMatch) { unsubMatch(); unsubMatch = null; }
-  matchId = null;
-}
-
-export async function sendMove(fen, move, moveCount) {
-  if (!matchId) return;
-  lastMoveCount = moveCount;
-  return net.post('game.php', {
-    action: 'move',
-    match_id: matchId,
-    fen,
-    move: JSON.stringify(move),
-    move_count: moveCount
-  });
-}
-
-export async function sendResign() {
-  if (!matchId) return;
-  return net.post('game.php', { action: 'resign', match_id: matchId });
-}
-
-export async function sendDrawOffer() {
-  if (!matchId) return;
-  const gs = JSON.stringify({ draw_offer: store.get('auth.userId') });
-  return net.post('game.php', { action: 'move', match_id: matchId, game_state: gs });
-}
-
-export async function sendEmote(emoteKey) {
-  if (!matchId) return;
-  const gs = JSON.stringify({ emote: { key: emoteKey, from: store.get('auth.userId'), t: Date.now() } });
-  return net.post('game.php', { action: 'move', match_id: matchId, game_state: gs });
-}
-
-export function getMatchId() { return matchId; }

public/js/modules/chess/scenes/result.js

@@ -132,7 +132,7 @@ export function mountResult(el, params) {
     el.querySelector('#btn-rematch')?.addEventListener('click', () => {
       audio.play('click');
       juice.hapticLight();
-      scene.replace('chess-game', { mode, botId, timeControl: 'rapid_10_0' });
+      scene.replace('chess-game', { mode, botId, timeControl: params.timeControl || 'rapid_10_0' });
     });
   }
 

public/js/modules/ludo/logic/live.js

-// Ludo Live Multiplayer — realtime game sync via Supabase
-import * as realtime from '../../../core/realtime.js';
-import * as net from '../../../core/net.js';
-import * as store from '../../../core/store.js';
-
-let unsubMatch = null;
-let matchId = null;
-let onUpdate = null;
-
-export function joinMatch(id, callback) {
-  matchId = id;
-  onUpdate = callback;
-
-  realtime.connect();
-  unsubMatch = realtime.subscribeLudoMatch(id, (change) => {
-    if (change.type === 'UPDATE' && change.new) {
-      if (onUpdate) onUpdate(change.new);
-    }
-  });
-}
-
-export function leaveMatch() {
-  if (unsubMatch) { unsubMatch(); unsubMatch = null; }
-  matchId = null;
-}
-
-export async function sendRoll(diceValue, positions, currentTurn, moves) {
-  if (!matchId) return;
-  return net.post('ludo.php', {
-    action: 'move',
-    match_id: matchId,
-    positions: positions,
-    current_turn: currentTurn,
-    dice_value: diceValue,
-    moves: moves
-  });
-}
-
-export async function sendEnd(winners) {
-  if (!matchId) return;
-  return net.post('ludo.php', { action: 'end', match_id: matchId, winners });
-}
-
-export function getMatchId() { return matchId; }

public/js/modules/play/scenes/challenge.js

@@ -205,6 +205,7 @@ function showChallengeOptions(el, targetId, targetName, friendProfile) {
       });
 
       if (res.error) { sendBtn.textContent = res.error; sendBtn.disabled = false; return; }
+      if (!res.match_id) { sendBtn.textContent = 'فشل إنشاء المباراة'; sendBtn.disabled = false; return; }
 
       // Also send a chat message
       net.post('chat.php', {

public/js/modules/play/scenes/lobby.js

@@ -128,8 +128,12 @@ export function mountLobby(el, params = {}) {
   if (isHost) {
     pollTimer = setInterval(() => pollMatchStatus(el, params), 2000);
   } else {
-    // Guest already accepted — can start immediately
-    startGame(el, params);
+    // Guest: wait briefly so host can detect acceptance, then start
+    const statusEl = el.querySelector('#lobby-status');
+    if (statusEl) {
+      statusEl.innerHTML = `<div class="lobby-status-text" style="color:#34D399;">${emoji('check', '✓', 14)} تم القبول! جاري تجهيز المباراة...</div>`;
+    }
+    setTimeout(() => startGame(el, params), 2500);
   }
 }