fix(export): prevent card stats poll overlap with frontend/backend singleflight

electron/services/chatService.ts

@@ -276,6 +276,12 @@ class ChatService {
   private exportContentStatsRefreshPromise: Promise<void> | null = null
   private exportContentStatsRefreshQueued = false
   private exportContentStatsRefreshForceQueued = false
+  private exportContentSessionCountsInFlight: {
+    promise: Promise<{ success: boolean; data?: ExportContentSessionCounts; error?: string }>
+    forceRefresh: boolean
+    traceId: string
+    startedAt: number
+  } | null = null
   private exportContentStatsDirtySessionIds = new Set<string>()
   private exportContentScopeSessionIdsCache: { ids: string[]; updatedAt: number } | null = null
   private readonly exportContentScopeSessionIdsCacheTtlMs = 60 * 1000
@@ -2124,30 +2130,50 @@ class ChatService {
     traceId?: string
   }): Promise<{ success: boolean; data?: ExportContentSessionCounts; error?: string }> {
     const traceId = this.normalizeExportDiagTraceId(options?.traceId)
+    const forceRefresh = options?.forceRefresh === true
+    const triggerRefresh = options?.triggerRefresh !== false
     const stepStartedAt = this.startExportDiagStep({
       traceId,
       stepId: 'backend-get-export-content-session-counts',
       stepName: '获取导出卡片统计',
       message: '开始计算导出卡片统计',
       data: {
-        triggerRefresh: options?.triggerRefresh !== false,
-        forceRefresh: options?.forceRefresh === true
+        triggerRefresh,
+        forceRefresh
       }
     })
     let stepSuccess = false
     let stepError = ''
     let stepResult: ExportContentSessionCounts | undefined
+    let activePromise: Promise<{ success: boolean; data?: ExportContentSessionCounts; error?: string }> | null = null
+    let createdInFlight = false
 
     try {
+      if (this.exportContentSessionCountsInFlight) {
+        this.logExportDiag({
+          traceId,
+          source: 'backend',
+          level: 'info',
+          message: '复用进行中的导出卡片统计任务',
+          stepId: 'backend-get-export-content-session-counts',
+          stepName: '获取导出卡片统计',
+          status: 'running',
+          data: {
+            inFlightTraceId: this.exportContentSessionCountsInFlight.traceId,
+            inFlightForceRefresh: this.exportContentSessionCountsInFlight.forceRefresh,
+            requestedForceRefresh: forceRefresh,
+            inFlightElapsedMs: Date.now() - this.exportContentSessionCountsInFlight.startedAt
+          }
+        })
+        activePromise = this.exportContentSessionCountsInFlight.promise
+      } else {
+        const createdPromise = (async () => {
           const connectResult = await this.ensureConnected()
           if (!connectResult.success) {
-        stepError = connectResult.error || '数据库未连接'
             return { success: false, error: connectResult.error || '数据库未连接' }
           }
           this.refreshSessionMessageCountCacheScope()
 
-      const forceRefresh = options?.forceRefresh === true
-      const triggerRefresh = options?.triggerRefresh !== false
           const sessionIds = await this.listExportContentScopeSessionIds(forceRefresh, traceId)
           const sessionIdSet = new Set(sessionIds)
 
@@ -2180,10 +2206,10 @@ class ChatService {
 
             const hasMediaSnapshot = Boolean(entry && entry.mediaReady)
             if (hasMediaSnapshot) {
-          if (entry!.hasVoice) voiceSessions += 1
-          if (entry!.hasImage) imageSessions += 1
-          if (entry!.hasVideo) videoSessions += 1
-          if (entry!.hasEmoji) emojiSessions += 1
+              if (entry.hasVoice) voiceSessions += 1
+              if (entry.hasImage) imageSessions += 1
+              if (entry.hasVideo) videoSessions += 1
+              if (entry.hasEmoji) emojiSessions += 1
             } else {
               pendingMediaSessionSet.add(sessionId)
             }
@@ -2267,7 +2293,9 @@ class ChatService {
             void this.startExportContentStatsRefresh(false, traceId)
           }
 
-      stepResult = {
+          return {
+            success: true,
+            data: {
               totalSessions: sessionIds.length,
               textSessions,
               voiceSessions,
@@ -2278,16 +2306,38 @@ class ChatService {
               updatedAt: this.exportContentStatsScopeUpdatedAt,
               refreshing: this.exportContentStatsRefreshPromise !== null
             }
-      stepSuccess = true
-      return {
-        success: true,
-        data: stepResult
           }
+        })()
+        activePromise = createdPromise
+        this.exportContentSessionCountsInFlight = {
+          promise: createdPromise,
+          forceRefresh,
+          traceId,
+          startedAt: Date.now()
+        }
+        createdInFlight = true
+      }
+
+      if (!activePromise) {
+        stepError = '统计任务未初始化'
+        return { success: false, error: stepError }
+      }
+      const result = await activePromise
+      stepSuccess = result.success
+      if (result.success && result.data) {
+        stepResult = result.data
+      } else {
+        stepError = result.error || '未知错误'
+      }
+      return result
     } catch (e) {
       console.error('ChatService: 获取导出内容会话统计失败:', e)
       stepError = String(e)
       return { success: false, error: String(e) }
     } finally {
+      if (createdInFlight && activePromise && this.exportContentSessionCountsInFlight?.promise === activePromise) {
+        this.exportContentSessionCountsInFlight = null
+      }
       this.endExportDiagStep({
         traceId,
         stepId: 'backend-get-export-content-session-counts',

src/pages/ExportPage.tsx

@@ -971,6 +971,8 @@ function ExportPage() {
   const activeTaskCountRef = useRef(0)
   const hasBaseConfigReadyRef = useRef(false)
   const contentSessionCountsForceRetryRef = useRef(0)
+  const contentSessionCountsInFlightRef = useRef<Promise<void> | null>(null)
+  const contentSessionCountsInFlightTraceRef = useRef('')
 
   const appendFrontendDiagLog = useCallback((entry: ExportCardDiagLogEntry) => {
     setFrontendDiagLogs(prev => {
@@ -1537,8 +1539,25 @@ function ExportPage() {
   }, [])
 
   const loadContentSessionCounts = useCallback(async (options?: { silent?: boolean; forceRefresh?: boolean }) => {
+    if (contentSessionCountsInFlightRef.current) {
+      logFrontendDiag({
+        level: 'info',
+        stepId: 'frontend-load-content-session-counts',
+        stepName: '前端请求导出卡片统计',
+        status: 'running',
+        message: '统计请求仍在进行中，跳过本次轮询',
+        data: {
+          silent: options?.silent === true,
+          forceRefresh: options?.forceRefresh === true,
+          inFlightTraceId: contentSessionCountsInFlightTraceRef.current || undefined
+        }
+      })
+      return
+    }
+
     const traceId = createExportDiagTraceId()
     const startedAt = Date.now()
+    const task = (async () => {
       logFrontendDiag({
         traceId,
         stepId: 'frontend-load-content-session-counts',
@@ -1567,7 +1586,7 @@ function ExportPage() {
             stepName: '前端请求导出卡片统计',
             status: 'timeout',
             durationMs: Date.now() - startedAt,
-          message: '导出卡片统计请求超时（3200ms）'
+            message: '导出卡片统计请求超时（3200ms，后台可能仍在处理）'
           })
           return
         }
@@ -1662,6 +1681,18 @@ function ExportPage() {
           data: { error: String(error) }
         })
       }
+    })()
+
+    contentSessionCountsInFlightRef.current = task
+    contentSessionCountsInFlightTraceRef.current = traceId
+    try {
+      await task
+    } finally {
+      if (contentSessionCountsInFlightRef.current === task) {
+        contentSessionCountsInFlightRef.current = null
+        contentSessionCountsInFlightTraceRef.current = ''
+      }
+    }
   }, [logFrontendDiag])
 
   const loadSessions = useCallback(async () => {