暂停继续

frontend-web/src/open-canvas/components/ai-writing/AIWritingPanel.tsx

@@ -1,6 +1,6 @@
 import { useCallback, useEffect, useRef, useState } from 'react';
 import { useNavigate } from 'react-router-dom';
-import { ChevronsDown, Plus, RotateCcw, Settings2, Square } from 'lucide-react';
+import { ChevronsDown, Play, Plus, RotateCcw, Settings2, Square } from 'lucide-react';
 
 import { Button } from '@/components/ui/button';
 import { cn } from '@/lib/utils';
@@ -38,7 +38,7 @@ const STATUS_LABEL: Record<string, string> = {
 export function AIWritingPanel() {
   const navigate = useNavigate();
   const { setArtifact } = useCanvasGraphContext();
-  const { state, startWriting, submitIntervention, stopWriting, reset } = useAIWriting();
+  const { state, startWriting, submitIntervention, pauseWriting, resumeWriting, reset } = useAIWriting();
   const { sessions, loading: sessionsLoading, refresh, rename, remove } = useAIWritingSessions();
 
   // History view state — null means normal writing mode
@@ -48,7 +48,7 @@ export function AIWritingPanel() {
   const isDone = state.status === 'done';
   const isError = state.status === 'error';
   const isRunning = !isIdle && !isDone && !isError;
-  const showSkeleton = isRunning && !state.currentPause;
+  const showSkeleton = isRunning && !state.currentPause && !state.isPaused;
 
   // ── 自动滚底逻辑 ────────────────────────────────────────────────────────────
   const scrollRef = useRef<HTMLDivElement>(null);
@@ -212,12 +212,34 @@ export function AIWritingPanel() {
               新建
             </Button>
           )}
-          {isRunning && (
-            <Button variant="ghost" size="sm" className="h-7 px-2 text-xs gap-1" onClick={stopWriting}>
-              <Square className="size-3" />
+          {isRunning && !state.isPaused && (
+            <Button
+              variant="ghost"
+              size="sm"
+              className="h-7 px-2 text-xs gap-1 animate-breathe-stop text-red-400 hover:text-red-500 hover:bg-red-50 dark:hover:bg-red-950/30"
+              onClick={pauseWriting}
+            >
+              <Square className="size-3 fill-current" />
               停止
             </Button>
           )}
+          {state.isPaused && (
+            <>
+              <Button
+                variant="ghost"
+                size="sm"
+                className="h-7 px-2 text-xs gap-1 text-primary hover:text-primary hover:bg-primary/8"
+                onClick={resumeWriting}
+              >
+                <Play className="size-3 fill-current" />
+                继续
+              </Button>
+              <Button variant="ghost" size="sm" className="h-7 px-2 text-xs gap-1" onClick={reset}>
+                <RotateCcw className="size-3" />
+                重置
+              </Button>
+            </>
+          )}
           {(isDone || isError) && (
             <Button variant="ghost" size="sm" className="h-7 px-2 text-xs gap-1" onClick={reset}>
               <RotateCcw className="size-3" />
@@ -336,10 +358,19 @@ export function AIWritingPanel() {
             isError ? 'text-destructive' : 'text-muted-foreground',
           )}
         >
-          {isRunning && (
-            <span className="inline-block size-1.5 rounded-full bg-blue-500 animate-pulse" />
+          {state.isPaused ? (
+            <>
+              <span className="inline-block size-1.5 rounded-full bg-amber-400" />
+              已暂停
+            </>
+          ) : (
+            <>
+              {isRunning && (
+                <span className="inline-block size-1.5 rounded-full bg-blue-500 animate-pulse" />
+              )}
+              {STATUS_LABEL[state.status] ?? state.status}
+            </>
           )}
-          {STATUS_LABEL[state.status] ?? state.status}
         </div>
       )}
     </div>

frontend-web/src/open-canvas/hooks/useAIWriting.ts

@@ -1,7 +1,7 @@
 import { useCallback, useEffect, useRef, useState } from 'react';
 
 import { useCanvasGraphContext } from '../contexts/CanvasGraphContext';
-import { startWritingSession, subscribeToProgress, resumeWriting } from '../api/ai-writing';
+import { startWritingSession, subscribeToProgress, resumeWriting as resumeWritingApi } from '../api/ai-writing';
 import type {
   AIWritingRequest,
   AIWritingState,
@@ -19,6 +19,7 @@ import type {
 const INITIAL_STATE: AIWritingState = {
   sessionId: null,
   status: 'idle',
+  isPaused: false,
   progressEvents: [],
   materials: [],
   outline: null,
@@ -194,6 +195,9 @@ export function useAIWriting() {
 
           case 'await_user': {
             const pp = event.pausePoint;
+            // Skip duplicate on SSE reconnect: backend re-injects the saved await_user event
+            // when queue is empty. If we already have this pause set, nothing needs to change.
+            if (prev.currentPause?.pausePoint === pp) return prev;
             const pauseStatus = pp
               ? (`awaiting_${pp}` as AIWritingState['status'])
               : prev.status;
@@ -273,6 +277,18 @@ export function useAIWriting() {
     async (payload: UserInterventionPayload) => {
       if (!state.sessionId || !state.currentPause) return;
 
+      // 若处于暂停状态，先重连 SSE 再提交，实现"干预即续接"
+      if (state.isPaused) {
+        abortRef.current?.abort();
+        abortRef.current = new AbortController();
+        unsubRef.current = subscribeToProgress(
+          state.sessionId,
+          handleEvent,
+          abortRef.current.signal,
+        );
+        setState((prev) => ({ ...prev, isPaused: false }));
+      }
+
       const pausePoint = state.currentPause.pausePoint;
       const record: CompletedIntervention = {
         pausePoint: pausePoint as CompletedIntervention['pausePoint'],
@@ -323,7 +339,7 @@ export function useAIWriting() {
       }
 
       try {
-        await resumeWriting(state.sessionId, payload);
+        await resumeWritingApi(state.sessionId, payload);
         setState((prev) => ({
           ...prev,
           currentPause: null,
@@ -340,16 +356,28 @@ export function useAIWriting() {
         setState((prev) => ({ ...prev, error: String(err) }));
       }
     },
-    [state.sessionId, state.currentPause, state.materials, state.outline,
-     state.currentDraftTitle, state.currentDraftMarkdown, state.reviewResult],
+    [state.sessionId, state.currentPause, state.isPaused, state.materials, state.outline,
+     state.currentDraftTitle, state.currentDraftMarkdown, state.reviewResult, handleEvent],
   );
 
-  const stopWriting = useCallback(() => {
+  const pauseWriting = useCallback(() => {
     abortRef.current?.abort();
     unsubRef.current?.();
-    setState((prev) => ({ ...prev, status: 'idle' }));
+    setState((prev) => ({ ...prev, isPaused: true }));
   }, []);
 
+  const resumeWriting = useCallback(() => {
+    if (!state.sessionId) return;
+    abortRef.current?.abort();
+    abortRef.current = new AbortController();
+    unsubRef.current = subscribeToProgress(
+      state.sessionId,
+      handleEvent,
+      abortRef.current.signal,
+    );
+    setState((prev) => ({ ...prev, isPaused: false }));
+  }, [state.sessionId, handleEvent]);
+
   const reset = useCallback(() => {
     abortRef.current?.abort();
     unsubRef.current?.();
@@ -359,5 +387,5 @@ export function useAIWriting() {
 
   useEffect(() => () => { abortRef.current?.abort(); }, []);
 
-  return { state, startWriting, submitIntervention, stopWriting, reset };
+  return { state, startWriting, submitIntervention, pauseWriting, resumeWriting, reset };
 }

frontend-web/src/open-canvas/types/ai-writing.ts

@@ -184,6 +184,7 @@ export interface CompletedIntervention {
 export interface AIWritingState {
   sessionId: string | null;
   status: WritingStatus;
+  isPaused: boolean;
   progressEvents: ProgressEvent[];
   materials: AIMaterial[];
   outline: AIOutline | null;

offline-backend-20260512/backend/app/gateway/routers/ai_writing.py

@@ -130,6 +130,12 @@ _session_error_flags: dict[str, bool] = {}
 # session_id → valid_article_types（list[dict] with key/label）
 _session_article_types: dict[str, list[dict]] = {}
 
+# session_id → pending await_user event tuple for SSE reconnect re-delivery
+# asyncio.Queue is consume-once; if the old SSE generator dequeued the await_user event
+# before the client disconnected, the event is lost from the queue. We save a copy here
+# so that a new SSE connection (e.g., after user clicks "继续") can re-inject it.
+_session_pending_pause: dict[str, tuple] = {}
+
 
 # ── 工具函数 ──────────────────────────────────────────────────────────────────
 
@@ -403,6 +409,9 @@ async def resume_writing(session_id: str, body: ResumeRequest, request: Request)
             except Exception:
                 logger.exception("ai_writing: failed to save intervention: session=%s", session_id)
 
+    # Clear pending pause so SSE reconnect won't re-inject the stale await_user event
+    _session_pending_pause.pop(session_id, None)
+
     asyncio.create_task(
         _stream_graph_segment(session_id, Command(resume=intervention), config, AI_WRITING_GRAPH)
     )
@@ -450,7 +459,11 @@ async def _stream_graph_segment(
                 interrupt_list = node_output if isinstance(node_output, (list, tuple)) else [node_output]
                 for intr in interrupt_list:
                     interrupt_data = intr.value if hasattr(intr, "value") else intr
-                    await queue.put(("await_user", interrupt_data))
+                    event_tuple = ("await_user", interrupt_data)
+                    await queue.put(event_tuple)
+                    # Save for SSE reconnect re-delivery: if the old generator consumed this
+                    # event before the client disconnected, a new connection would block forever.
+                    _session_pending_pause[session_id] = event_tuple
                 return  # 等待 resume，不关闭队列
 
             if not isinstance(node_output, dict):
@@ -552,6 +565,7 @@ async def _stream_graph_segment(
             _session_interventions.pop(session_id, None)
             _session_error_flags.pop(session_id, None)
             _session_article_types.pop(session_id, None)
+            _session_pending_pause.pop(session_id, None)
 
 
 def _event_type(evt: dict) -> str:
@@ -577,6 +591,12 @@ async def _sse_generator(session_id: str) -> AsyncGenerator[str, None]:
     queue = _event_queues[session_id]
     yield _sse("connected", {"session_id": session_id})
 
+    # Re-inject the saved await_user event if the queue is empty and a pending pause exists.
+    # This covers the case where the old SSE generator dequeued the await_user event and
+    # yielded it to a disconnecting client — the event is then lost from the consume-once queue.
+    if queue.empty() and session_id in _session_pending_pause:
+        await queue.put(_session_pending_pause[session_id])
+
     while True:
         item = await queue.get()
         if item is None: