apps/web/src/api/generation/types.ts

@@ -38,6 +38,8 @@ export interface CreatePreviewResponse {
   is_preview: boolean
   resolution: string
   created_at: string
+  /** 后端自动关联的编辑计划 ID（用于 fallback 路径传递 source_edit_plan_id） */
+  source_edit_plan_id?: string
 }
 
 /** 预览任务详情响应 */

apps/web/src/pages/generate/GeneratePage.tsx

@@ -9,7 +9,7 @@
  * - 标题样式通过 CSS 层实时叠加，所见即所得
  * - 最终成片仍走后端 FFmpeg 渲染（Step7 确认生成）
  */
-import React, { useMemo, useEffect } from "react"
+import React, { useMemo } from "react"
 import { Modal, message } from "antd"
 import { useNavigate } from "react-router-dom"
 import type { VoiceClone } from "@/api/voice-clone"
@@ -79,6 +79,8 @@ const GeneratePage: React.FC = () => {
     setPreviewModalOpen,
     previewTaskId,
     setPreviewTaskId,
+    storedSourceEditPlanId,
+    setStoredSourceEditPlanId,
   } = formState
 
   /* ── 标题样式回调（Step5 样式面板 + 右侧预览 CSS 层共用） ── */
@@ -101,13 +103,10 @@ const GeneratePage: React.FC = () => {
     () => (materialMode === "auto" ? smartSelectedIds : selectedMaterials),
     [materialMode, smartSelectedIds, selectedMaterials],
   )
-  // 素材、模板或生成参数变化时，清除旧的 previewTaskId，防止 Step7 复用过期预览产物
-  // confirmGeneration 无法覆盖 duration/ratio/title_config，所以这些参数变化后必须重新创建预览
-  const titleKey = JSON.stringify(titleSettings)
-  useEffect(() => {
-    setPreviewTaskId(null)
-    // eslint-disable-next-line react-hooks/exhaustive-deps
-  }, [previewAssetIds, selectedTemplate, duration, videoRatio, titleKey, bgm, setPreviewTaskId])
+  // previewTaskId 不再因设置变化而自动清除。
+  // 用户修改设置后，confirmGeneration 会检测参数是否匹配：
+  // 匹配则复用产物秒出；不匹配则后端自动 fallback 到 createGenerationTask 重新渲染。
+  // 只有当用户明确返回 Step5 重新预览时，才会创建新的预览任务并覆盖 previewTaskId。
 
   const previewAssetsEnabled = currentStep >= 4 && previewAssetIds.length > 0
   const {
@@ -182,7 +181,7 @@ const GeneratePage: React.FC = () => {
     autoSubtitles,
     bgm,
     generateCount,
-    sourceEditPlanId,
+    sourceEditPlanId: storedSourceEditPlanId || sourceEditPlanId,
     previewTaskId,
   })
 
@@ -227,6 +226,7 @@ const GeneratePage: React.FC = () => {
             activePreset={styleUpdaters.activePreset}
             titlePresets={styleUpdaters.titlePresets}
             onPreviewTaskCreated={setPreviewTaskId}
+            onSourceEditPlanIdExtracted={setStoredSourceEditPlanId}
             coverSettings={coverSettings}
             onCoverSettingsChange={setCoverSettings}
             duration={duration}

apps/web/src/pages/generate/components/GenerateStepContent.tsx

@@ -78,6 +78,8 @@ export interface GenerateStepContentProps {
   presetVoices: PresetVoiceItem[]
   /** 预览任务创建回调——传递给 Step6CoverSettings */
   onPreviewTaskCreated?: (taskId: string) => void
+  /** 从预览响应中提取到 source_edit_plan_id 时的回调 */
+  onSourceEditPlanIdExtracted?: (planId: string) => void
 }
 
 export const GenerateStepContent: React.FC<GenerateStepContentProps> = (props) => {
@@ -124,6 +126,7 @@ export const GenerateStepContent: React.FC<GenerateStepContentProps> = (props) =
     onDismissError,
     presetVoices,
     onPreviewTaskCreated,
+    onSourceEditPlanIdExtracted,
   } = props
 
   /* 当前模板的 segments，传给 Step2 构建 clips */
@@ -194,6 +197,7 @@ export const GenerateStepContent: React.FC<GenerateStepContentProps> = (props) =
           selectedTemplate={selectedTemplate}
           titleSettings={titleSettings}
           onPreviewTaskCreated={onPreviewTaskCreated}
+          onSourceEditPlanIdExtracted={onSourceEditPlanIdExtracted}
         />
       )
     case 7:

apps/web/src/pages/generate/components/Step6CoverSettings.tsx

@@ -18,6 +18,8 @@ interface Step6CoverSettingsProps {
   titleSettings?: import("../types").TitleSettings
   /** 预览任务创建回调——将 task_id 暴露给父组件供 confirmGeneration 复用 */
   onPreviewTaskCreated?: (taskId: string) => void
+  /** 从预览响应中提取到 source_edit_plan_id 时的回调 */
+  onSourceEditPlanIdExtracted?: (planId: string) => void
 }
 
 const Step6CoverSettings: React.FC<Step6CoverSettingsProps> = (props) => {
@@ -46,6 +48,7 @@ const Step6CoverSettings: React.FC<Step6CoverSettingsProps> = (props) => {
     selectedTemplate: props.selectedTemplate,
     titleSettings: props.titleSettings,
     onPreviewTaskCreated: props.onPreviewTaskCreated,
+    onSourceEditPlanIdExtracted: props.onSourceEditPlanIdExtracted,
   })
 
   const handleAutoGenerate = () => {

apps/web/src/pages/generate/hooks/useGenerateFormState/index.ts

@@ -99,6 +99,10 @@ export interface GenerateFormState {
   /** 预览任务 ID（由 useStep6Cover 创建后写入，供 useGenerateVideo 复用） */
   previewTaskId: string | null
   setPreviewTaskId: (id: string | null) => void
+
+  /** 从预览响应中提取的 source_edit_plan_id（供 fallback 路径使用） */
+  storedSourceEditPlanId: string | null
+  setStoredSourceEditPlanId: (planId: string | null) => void
 }
 
 export const useGenerateFormState = (): GenerateFormState => {
@@ -167,6 +171,9 @@ export const useGenerateFormState = (): GenerateFormState => {
   /* ── 预览任务 ID（useStep6Cover 创建预览时写入，useGenerateVideo 复用） ── */
   const [previewTaskId, setPreviewTaskId] = useState<string | null>(null)
 
+  /* ── 从预览响应中提取的 source_edit_plan_id（供 fallback 路径使用） ── */
+  const [storedSourceEditPlanId, setStoredSourceEditPlanId] = useState<string | null>(null)
+
   /* ── 从 URL / 编辑计划加载配置 ── */
   usePlanConfigLoader({
     editPlanId,
@@ -217,5 +224,7 @@ export const useGenerateFormState = (): GenerateFormState => {
     setPreviewModalOpen,
     previewTaskId,
     setPreviewTaskId,
+    storedSourceEditPlanId,
+    setStoredSourceEditPlanId,
   }
 }

apps/web/src/pages/generate/hooks/useStep6Cover.ts

@@ -28,6 +28,8 @@ interface UseStep6CoverProps {
   titleSettings?: TitleSettings
   /** 预览任务创建回调——将 task_id 暴露给父组件供 confirmGeneration 复用 */
   onPreviewTaskCreated?: (taskId: string) => void
+  /** 从预览响应中提取到 source_edit_plan_id 时的回调 */
+  onSourceEditPlanIdExtracted?: (planId: string) => void
 }
 
 export function useStep6Cover({
@@ -38,6 +40,7 @@ export function useStep6Cover({
   selectedTemplate = "",
   titleSettings,
   onPreviewTaskCreated,
+  onSourceEditPlanIdExtracted,
 }: UseStep6CoverProps) {
   const [generating, setGenerating] = useState(false)
   // 防竞态：记录当前预览生成的参数指纹，任务完成时校验一致性
@@ -181,6 +184,10 @@ export function useStep6Cover({
           const currentFingerprint = JSON.stringify({ selectedTemplate, assetIds, titleSettings })
           if (previewResp.task_id && previewParamsRef.current === currentFingerprint) {
             onPreviewTaskCreated?.(previewResp.task_id)
+            // 提取后端自动关联的 source_edit_plan_id，供 fallback 路径使用
+            if (previewResp.source_edit_plan_id) {
+              onSourceEditPlanIdExtracted?.(previewResp.source_edit_plan_id)
+            }
           }
           // 轮询等待预览渲染完成：递归 setTimeout 避免请求重叠 + 120s 超时兜底
           await new Promise<void>((resolve, reject) => {
@@ -295,6 +302,7 @@ export function useStep6Cover({
     duration,
     titleSettings,
     onPreviewTaskCreated,
+    onSourceEditPlanIdExtracted,
   ])
 
   // ── 模板操作方法 ──