feat: add message stall detection and soft resync in event stream

packages/ui/src/hooks/useEventStream.ts

@@ -22,6 +22,16 @@ interface EventData {
   properties?: Record<string, unknown>;
 }
 
+const readStringProp = (obj: unknown, keys: string[]): string | null => {
+  if (!obj || typeof obj !== 'object') return null;
+  const record = obj as Record<string, unknown>;
+  for (let i = 0; i < keys.length; i++) {
+    const value = record[keys[i]];
+    if (typeof value === 'string' && value.length > 0) return value;
+  }
+  return null;
+};
+
 type MessageTracker = (messageId: string, event?: string, extraData?: Record<string, unknown>) => void;
 
 declare global {
@@ -347,6 +357,10 @@ export const useEventStream = () => {
     [resyncMessages]
   );
 
+  React.useEffect(() => {
+    scheduleSoftResyncRef.current = scheduleSoftResync;
+  }, [scheduleSoftResync]);
+
   const trackMessage = React.useCallback((messageId: string, event?: string, extraData?: Record<string, unknown>) => {
     if (streamDebugEnabled()) {
       console.debug(`[MessageTracker] ${messageId}: ${event}`, extraData);
@@ -389,6 +403,14 @@ export const useEventStream = () => {
   const pauseTimeoutRef = React.useRef<NodeJS.Timeout | null>(null);
   const staleCheckIntervalRef = React.useRef<NodeJS.Timeout | null>(null);
   const lastEventTimestampRef = React.useRef<number>(Date.now());
+  const lastMessageEventBySessionRef = React.useRef<Map<string, number>>(new Map());
+  const pendingMessageStallTimersRef = React.useRef<Map<string, NodeJS.Timeout>>(new Map());
+  const lastMessageStallRecoveryBySessionRef = React.useRef<Map<string, number>>(new Map());
+
+  const scheduleSoftResyncRef = React.useRef<
+    (sessionId: string, reason: string, limit?: number) => Promise<void>
+  >(() => Promise.resolve());
+  const scheduleReconnectRef = React.useRef<(hint?: string) => void>(() => {});
   const isDesktopRuntimeRef = React.useRef<boolean>(false);
 
   const maybeBootstrapIfStale = React.useCallback(
@@ -493,6 +515,52 @@ export const useEventStream = () => {
       return;
     }
 
+    const shouldArmMessageStallCheck = storePhase === 'idle' && (phase === 'busy' || phase === 'cooldown');
+    const shouldDisarmMessageStallCheck = phase === 'idle';
+
+    if (shouldDisarmMessageStallCheck) {
+      const pending = pendingMessageStallTimersRef.current.get(sessionId);
+      if (pending) {
+        clearTimeout(pending);
+        pendingMessageStallTimersRef.current.delete(sessionId);
+      }
+    }
+
+    if (shouldArmMessageStallCheck) {
+      const pending = pendingMessageStallTimersRef.current.get(sessionId);
+      if (pending) {
+        clearTimeout(pending);
+        pendingMessageStallTimersRef.current.delete(sessionId);
+      }
+
+      const startAt = Date.now();
+      const timer = setTimeout(() => {
+        const currentPhase = useSessionStore.getState().sessionActivityPhase?.get(sessionId);
+        if (currentPhase !== 'busy' && currentPhase !== 'cooldown') {
+          return;
+        }
+
+        const lastRecoveryAt = lastMessageStallRecoveryBySessionRef.current.get(sessionId) ?? 0;
+        if (Date.now() - lastRecoveryAt < 15000) {
+          return;
+        }
+
+        const lastMsgAt = lastMessageEventBySessionRef.current.get(sessionId) ?? 0;
+        if (lastMsgAt >= startAt) {
+          return;
+        }
+
+        lastMessageStallRecoveryBySessionRef.current.set(sessionId, Date.now());
+
+        void scheduleSoftResyncRef.current(sessionId, 'activity_started_no_message', getActiveSessionWindow())
+          .finally(() => {
+            scheduleReconnectRef.current('No message events after activity start');
+          });
+      }, 2000);
+
+      pendingMessageStallTimersRef.current.set(sessionId, timer);
+    }
+
     const existingTimer = sessionCooldownTimersRef.current.get(sessionId);
     if (existingTimer) {
       clearTimeout(existingTimer);
@@ -737,25 +805,19 @@ export const useEventStream = () => {
         const partExt = part as Record<string, unknown>;
         const messageInfo = (typeof props.info === 'object' && props.info !== null) ? (props.info as Record<string, unknown>) : props;
 
-        const messageInfoSessionId = typeof (messageInfo as { sessionID?: unknown }).sessionID === 'string'
+        const messageInfoSessionId = readStringProp(messageInfo, ['sessionID', 'sessionId']);
-          ? (messageInfo as { sessionID?: string }).sessionID
-          : null;
 
         const resolvedSessionId =
-          (typeof partExt.sessionID === 'string' && (partExt.sessionID as string).length > 0) ? (partExt.sessionID as string) :
+          readStringProp(partExt, ['sessionID', 'sessionId']) ||
-          (typeof messageInfoSessionId === 'string' && messageInfoSessionId.length > 0) ? messageInfoSessionId :
+          messageInfoSessionId ||
-          (typeof props.sessionID === 'string' && (props.sessionID as string).length > 0) ? (props.sessionID as string) :
+          readStringProp(props, ['sessionID', 'sessionId']);
-          null;
 
-        const messageInfoId = typeof (messageInfo as { id?: unknown }).id === 'string'
+        const messageInfoId = readStringProp(messageInfo, ['messageID', 'messageId', 'id']);
-          ? (messageInfo as { id?: string }).id
-          : null;
 
         const resolvedMessageId =
-          (typeof partExt.messageID === 'string' && (partExt.messageID as string).length > 0) ? (partExt.messageID as string) :
+          readStringProp(partExt, ['messageID', 'messageId']) ||
-          (typeof messageInfoId === 'string' && messageInfoId.length > 0) ? messageInfoId :
+          messageInfoId ||
-          (typeof props.messageID === 'string' && (props.messageID as string).length > 0) ? (props.messageID as string) :
+          readStringProp(props, ['messageID', 'messageId']);
-          null;
 
         if (!resolvedSessionId || !resolvedMessageId) {
           if (streamDebugEnabled()) {
@@ -770,6 +832,13 @@ export const useEventStream = () => {
         const sessionId = resolvedSessionId;
         const messageId = resolvedMessageId;
 
+        lastMessageEventBySessionRef.current.set(sessionId, Date.now());
+        const pendingTimer = pendingMessageStallTimersRef.current.get(sessionId);
+        if (pendingTimer) {
+          clearTimeout(pendingTimer);
+          pendingMessageStallTimersRef.current.delete(sessionId);
+        }
+
         const trimmedHeadMaxId = useSessionStore.getState().sessionMemoryState.get(sessionId)?.trimmedHeadMaxId;
         if (trimmedHeadMaxId && !isIdNewer(messageId, trimmedHeadMaxId)) {
           if (streamDebugEnabled()) {
@@ -817,14 +886,12 @@ export const useEventStream = () => {
         const messageExt = message as Record<string, unknown>;
 
         const resolvedSessionId =
-          (typeof messageExt.sessionID === 'string' && (messageExt.sessionID as string).length > 0) ? (messageExt.sessionID as string) :
+          readStringProp(messageExt, ['sessionID', 'sessionId']) ||
-          (typeof props.sessionID === 'string' && (props.sessionID as string).length > 0) ? (props.sessionID as string) :
+          readStringProp(props, ['sessionID', 'sessionId']);
-          null;
 
         const resolvedMessageId =
-          (typeof messageExt.id === 'string' && (messageExt.id as string).length > 0) ? (messageExt.id as string) :
+          readStringProp(messageExt, ['messageID', 'messageId', 'id']) ||
-          (typeof props.messageID === 'string' && (props.messageID as string).length > 0) ? (props.messageID as string) :
+          readStringProp(props, ['messageID', 'messageId']);
-          null;
 
         if (!resolvedSessionId || !resolvedMessageId) {
           if (streamDebugEnabled()) {
@@ -839,6 +906,13 @@ export const useEventStream = () => {
         const sessionId = resolvedSessionId;
         const messageId = resolvedMessageId;
 
+        lastMessageEventBySessionRef.current.set(sessionId, Date.now());
+        const pendingTimer = pendingMessageStallTimersRef.current.get(sessionId);
+        if (pendingTimer) {
+          clearTimeout(pendingTimer);
+          pendingMessageStallTimersRef.current.delete(sessionId);
+        }
+
         const trimmedHeadMaxId = useSessionStore.getState().sessionMemoryState.get(sessionId)?.trimmedHeadMaxId;
         if (trimmedHeadMaxId && !isIdNewer(messageId, trimmedHeadMaxId)) {
           if (streamDebugEnabled()) {
@@ -1776,6 +1850,10 @@ export const useEventStream = () => {
     }, delay);
   }, [shouldHoldConnection, stopStream, publishStatus, startStream]);
 
+  React.useEffect(() => {
+    scheduleReconnectRef.current = scheduleReconnect;
+  }, [scheduleReconnect]);
+
   React.useEffect(() => {
     const cooldownTimers = sessionCooldownTimersRef.current;
 
@@ -1930,6 +2008,7 @@ export const useEventStream = () => {
           const hasBusySessions = Array.from(useSessionStore.getState().sessionActivityPhase?.values?.() ?? []).some(
             (phase) => phase === 'busy' || phase === 'cooldown'
           );
+
           if (hasBusySessions) {
             void refreshSessionActivityStatus();
           }