From fa145dbf4270d20ed5cfb576436f71054c6a1bdc Mon Sep 17 00:00:00 2001
From: Chihiro Yamaguchi <chi5@Chihiros-Mac-Studio-4.local>
Date: Wed, 22 Jul 2026 01:44:45 +0900
Subject: [PATCH] Fix duplicate chat submits from Enter races and IME
 composition.

Guard submit with a synchronous localTurn ref and ignore Enter while an IME composition is active so one keypress cannot enqueue two agent turns.

Co-authored-by: Cursor <cursoragent@cursor.com>
---
 app/components/chat-composer.tsx      |  9 +++++----
 app/components/use-chat-controller.ts | 17 +++++++++++++----
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/app/components/chat-composer.tsx b/app/components/chat-composer.tsx
index ea4237d..fd43196 100644
--- a/app/components/chat-composer.tsx
+++ b/app/components/chat-composer.tsx
@@ -227,10 +227,11 @@ export function ChatComposer({
               value={input}
               onChange={(event) => onInputChange(event.target.value)}
               onKeyDown={(event) => {
-                if (event.key === "Enter" && !event.shiftKey) {
-                  event.preventDefault();
-                  submit();
-                }
+                if (event.key !== "Enter" || event.shiftKey) return;
+                // Japanese/other IME: Enter confirms composition; don't send yet.
+                if (event.nativeEvent.isComposing || event.keyCode === 229) return;
+                event.preventDefault();
+                submit();
               }}
               placeholder="Hey Aithy"
               className="max-h-60 min-h-11 overflow-y-auto rounded-none border-0 bg-transparent px-0 py-2.5 text-base leading-6 shadow-none placeholder:text-[rgb(var(--muted-foreground))]/75 focus:border-0"
diff --git a/app/components/use-chat-controller.ts b/app/components/use-chat-controller.ts
index 7561abe..976b7d0 100644
--- a/app/components/use-chat-controller.ts
+++ b/app/components/use-chat-controller.ts
@@ -148,6 +148,7 @@ export function useChatController({
         setStreamingDraft(null);
         const turnToComplete = localTurnRef.current;
         if (assistantCompletesLocalTurn(turnToComplete, event.conversationId, message.createdAt)) {
+          localTurnRef.current = IDLE_LOCAL_CHAT_TURN;
           setLocalTurn(IDLE_LOCAL_CHAT_TURN);
         }
       }
@@ -173,7 +174,10 @@ export function useChatController({
     const useSelectedSkills = options.useSelectedSkills ?? true;
     const skillsForTurn = options.selectedSkillsOverride
       ?? (useSelectedSkills ? selectedSkills : []);
-    if (turn.busy && activeSessionId && !options.pendingMessage) {
+    // Use the ref as well as React state: two Enter/clicks can race before setState
+    // re-renders, which used to POST the same chat turn twice.
+    const syncBusy = turn.busy || localTurnRef.current.phase !== "idle";
+    if (syncBusy && activeSessionId && !options.pendingMessage) {
       enqueuePending({
         conversationId: activeSessionId,
         text,
@@ -194,6 +198,7 @@ export function useChatController({
       taskId: null,
       phase: "submitting",
     };
+    localTurnRef.current = nextLocalTurn;
     setLocalTurn(nextLocalTurn);
     if (wasDraft) setActiveSessionId(conversationId);
     if (!isCommand) {
@@ -211,9 +216,11 @@ export function useChatController({
       });
       const taskId = taskIdFromResult(result);
       const queued = Boolean(result.queued && !isCommand);
-      setLocalTurn(queued
-        ? { ...nextLocalTurn, taskId, phase: "awaiting_reply" }
-        : IDLE_LOCAL_CHAT_TURN);
+      const settledTurn = queued
+        ? { ...nextLocalTurn, taskId, phase: "awaiting_reply" as const }
+        : IDLE_LOCAL_CHAT_TURN;
+      localTurnRef.current = settledTurn;
+      setLocalTurn(settledTurn);
       if (!isCommand && useSelectedSkills && !options.pendingMessage) setSelectedSkills([]);
       if (result.activeSessionId !== conversationId) {
         setActiveSessionId(result.activeSessionId);
@@ -222,6 +229,7 @@ export function useChatController({
         await navigateToSession(conversationId);
       }
     } catch (error) {
+      localTurnRef.current = IDLE_LOCAL_CHAT_TURN;
       setLocalTurn(IDLE_LOCAL_CHAT_TURN);
       if (options.pendingMessage) restorePending(options.pendingMessage);
       throw error;
@@ -255,6 +263,7 @@ export function useChatController({
   }, [input, submitText]);
 
   const stop = useCallback(() => {
+    localTurnRef.current = IDLE_LOCAL_CHAT_TURN;
     setLocalTurn(IDLE_LOCAL_CHAT_TURN);
     setStreamingDraft(null);
     if (activeSessionId) void stopChatMessage({ data: { conversationId: activeSessionId } });