fix(frontend): 保持重新生成退出前详情

frontend/src/views/data-process/create/useDataProcessGeneration.ts

@@ -15,7 +15,7 @@ import type { GenerationState, ResultItem } from './types'
 interface GenerationBindings {
   taskId: Ref<string | null>
   dirty: Ref<boolean>
-  beforeGenerate?: () => Promise<void>
+  beforeGenerate?: () => Promise<boolean | void>
 }
 
 const RESULT_PAGE_SIZE = 500
@@ -51,6 +51,7 @@ export function useDataProcessGeneration(bindings: GenerationBindings) {
   let generationTimer: ReturnType<typeof setTimeout> | null = null
   let generationRun = 0
   let pollFailureCount = 0
+  let generationStarting = false
 
   function stopGenerationTimer() {
     generationRun += 1
@@ -140,33 +141,39 @@ export function useDataProcessGeneration(bindings: GenerationBindings) {
   }
 
   async function startGeneration() {
+    if (generationStarting || generation.status === 'running') return
     const taskId = bindings.taskId.value
     if (!taskId) {
       ElMessage.error('任务尚未创建，请返回上一步重试')
       return
     }
 
-    stopGenerationTimer()
-    const runId = generationRun
-    generation.status = 'running'
-    pollFailureCount = 0
-    generation.progress = 0
-    generation.message = '正在同步预览修改并启动后端处理，请稍候。'
-
+    generationStarting = true
+    let runId: number | null = null
     try {
-      await bindings.beforeGenerate?.()
+      const canStart = await bindings.beforeGenerate?.()
+      if (canStart === false) return
+      stopGenerationTimer()
+      const activeRunId = generationRun
+      runId = activeRunId
+      generation.status = 'running'
+      pollFailureCount = 0
+      generation.progress = 0
+      generation.message = '正在同步预览修改并启动后端处理，请稍候。'
       const progress = await generateDataProcess(taskId)
-      if (runId !== generationRun) return
+      if (activeRunId !== generationRun) return
       if (progress.status === 'completed' || progress.status === 'failed' || progress.status === 'stopped') {
         await finishFromProgress(progress)
         return
       }
       applyProgress(progress)
-      generationTimer = setTimeout(() => void pollGeneration(runId), POLL_INTERVAL_MS)
+      generationTimer = setTimeout(() => void pollGeneration(activeRunId), POLL_INTERVAL_MS)
     } catch (error) {
-      if (runId !== generationRun) return
+      if (runId !== null && runId !== generationRun) return
       generation.status = 'failed'
       generation.message = error instanceof Error ? error.message : '启动数据处理失败，请重试。'
+    } finally {
+      generationStarting = false
     }
   }