style: auto-format with black + isort + prettier [skip ci-format-check]

修复3个断点导致预览视频不渲染用户自定义标题:

断点1(P0): generate_video() 未将 custom_title 传给 _render_video()
断点2(P0): _render_video() 没有接收 custom_title，也未注入 plan.config[title]
断点3(P1): generate_ass_from_timeline() ASR路径完全跳过标题渲染
次要: 前端 font_size/font_color 与后端 size/color 字段名不匹配

修改:
- generation.py: _render_video 增加 custom_title 参数，JSON解析+字段归一化后
  注入 virtual_plan.config[title]; generate_video 调用处传递 task_info[custom_title]
- subtitle_generator.py: generate_ass_from_timeline 增加 title_text/title_config/
  video_duration 参数，ASR字幕与标题共存于同一ASS文件
- unified_render_service.py: _maybe_generate_ass 的ASR路径传递标题参数
- 新增 test_preview_title_render.py (9个测试覆盖3个断点)

apps/api/app/api/routes/generation_preview.py

@@ -315,6 +315,32 @@ def create_preview_generation_task(
         logger.error("[预览生成] 创建失败: %s", e, exc_info=True)
         raise HTTPException(status_code=500, detail="创建预览生成任务失败，请稍后再试") from e
 
+    # 关联编辑计划：如果前端未传 source_edit_plan_id，通过 template_id + user_id 查找
+    if not task.source_edit_plan_id and request.template_id:
+        try:
+            from packages.adapters.sqlalchemy_impl.edit_plan_repository import (
+                SQLAlchemyEditPlanRepository,
+            )
+
+            _plan_repo = SQLAlchemyEditPlanRepository(db)
+            _plans = _plan_repo.list_by_template(request.template_id, limit=20)
+            for _p in _plans:
+                if (_p.created_by_user_id or "") == user_id:
+                    task.source_edit_plan_id = _p.id
+                    generation_task_repository.update(task)
+                    logger.info(
+                        "[预览生成] 自动关联编辑计划: task_id=%s plan_id=%s",
+                        task.id,
+                        _p.id,
+                    )
+                    break
+        except Exception:
+            logger.warning(
+                "[预览生成] 查找关联编辑计划失败（不影响主流程）: task_id=%s",
+                task.id,
+                exc_info=True,
+            )
+
     # 入队执行；若入队失败则标记任务为 failed 避免僵尸数据
     try:
         if not safe_enqueue_generation_task(

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

@@ -235,8 +235,6 @@ const GeneratePage: React.FC = () => {
             previewOverallError={step5Preview.previewError}
             previewOverallProgress={step5Preview.progress}
             previewAnyGenerating={step5Preview.anyGenerating}
-            previewTemplateName={step5Preview.templateName}
-            previewMaterialCount={step5Preview.materialCount}
             onGeneratePreview={step5Preview.generatePreview}
             onRegeneratePreview={step5Preview.regeneratePreview}
           />
@@ -254,7 +252,7 @@ const GeneratePage: React.FC = () => {
 
         {/* ════ 右侧：预览 + 生成结果 ════ */}
         <div className="xx-generate-right-col">
-          {/* 预览视频面板（Step4+ 常驻，Step4 显示标题预览，Step5+ 显示预览视频） */}
+          {/* 预览视频面板（Step4+ 显示，Step4 显示标题预览叠加，Step5+ 仅视频） */}
           {currentStep >= 4 && (
             <PreviewVideoPanel
               previewStatus={step5Preview.previewStatus}

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

@@ -74,8 +74,6 @@ export interface GenerateStepContentProps {
   previewOverallError: string
   previewOverallProgress: number
   previewAnyGenerating: boolean
-  previewTemplateName: string
-  previewMaterialCount: string
   onGeneratePreview: () => void
   onRegeneratePreview: () => void
 }
@@ -122,8 +120,6 @@ export const GenerateStepContent: React.FC<GenerateStepContentProps> = (props) =
     previewOverallError,
     previewOverallProgress,
     previewAnyGenerating,
-    previewTemplateName,
-    previewMaterialCount,
     onGeneratePreview,
     onRegeneratePreview,
   } = props
@@ -165,9 +161,6 @@ export const GenerateStepContent: React.FC<GenerateStepContentProps> = (props) =
     case 5:
       return (
         <Step5GeneratePreview
-          templateName={previewTemplateName}
-          materialCount={previewMaterialCount}
-          duration={duration}
           videoRatio={videoRatio}
           previewCount={previewCount}
           onPreviewCountChange={onPreviewCountChange}

apps/web/src/pages/generate/components/Step5GeneratePreview.tsx

@@ -15,9 +15,6 @@ import { InputNumber } from "antd"
 import type { PreviewItem, PreviewStatus } from "../hooks/useStep5Preview"
 
 interface Step5GeneratePreviewProps {
-  templateName: string
-  materialCount: string
-  duration: number
   videoRatio: string
   previewCount: number
   onPreviewCountChange: (count: number) => void
@@ -40,8 +37,6 @@ const PREVIEW_COUNT_OPTIONS = [
 ]
 
 const Step5GeneratePreview: React.FC<Step5GeneratePreviewProps> = ({
-  templateName: _templateName,
-  materialCount: _materialCount,
   videoRatio,
   previewCount,
   onPreviewCountChange,

apps/worker/video_processing/subtitle_generator.py

@@ -13,6 +13,16 @@ import logging
 from pathlib import Path
 from typing import Any
 
+from packages.domain.ass_subtitle_builder import (
+    TITLE_MARGIN_SIDE,
+    TITLE_MARGIN_TOP,
+    _wrap_title_text,
+    build_ass_style,
+    escape_ass_text,
+    format_ass_time,
+    hex_to_ass_color,
+    position_to_ass_alignment,
+)
 from packages.domain.subtitle import SubtitleTimeline
 
 logger = logging.getLogger(__name__)
@@ -100,7 +110,10 @@ def generate_ass_from_timeline(
     *,
     video_width: int,
     video_height: int,
+    video_duration: float = 0.0,
     subtitle_config: dict[str, Any] | None = None,
+    title_text: str = "",
+    title_config: dict[str, Any] | None = None,
 ) -> Path:
     """从字幕时间轴生成 ASS 字幕文件。
 
@@ -160,7 +173,76 @@ def generate_ass_from_timeline(
 
         events.append(f"Dialogue: 0,{start_time},{end_time},Default,,0,0,0,,{safe_text}")
 
-    # 组装 ASS 文件
+    # ── 标题样式与事件（叠加在 ASR 字幕之上）───────────────────────────
+    title_cfg = title_config or {}
+    if not isinstance(title_cfg, dict):
+        title_cfg = {}
+    title_enabled = title_cfg.get("enabled", True) and bool(title_text.strip())
+
+    title_style_line = ""
+    title_event_line = ""
+
+    if title_enabled:
+        # 兼容 boolean stroke/shadow → dict
+        _stroke_val = title_cfg.get("stroke")
+        if isinstance(_stroke_val, bool):
+            title_cfg["stroke"] = (
+                {"enabled": _stroke_val, "color": "#000000", "width": 2} if _stroke_val else {"enabled": False}
+            )
+        _shadow_val = title_cfg.get("shadow")
+        if isinstance(_shadow_val, bool):
+            title_cfg["shadow"] = (
+                {"enabled": _shadow_val, "color": "#000000", "blur": 4, "offset_x": 2, "offset_y": 2}
+                if _shadow_val
+                else {"enabled": False}
+            )
+
+        # 字段名归一化: font_size→size, font_color→color
+        if "font_size" in title_cfg and "size" not in title_cfg:
+            title_cfg["size"] = title_cfg["font_size"]
+        if "font_color" in title_cfg and "color" not in title_cfg:
+            title_cfg["color"] = title_cfg["font_color"]
+
+        t_color = hex_to_ass_color(title_cfg.get("color", "#ffffff"))
+        t_stroke = title_cfg.get("stroke", {}) or {}
+        t_shadow = title_cfg.get("shadow", {}) or {}
+        s_color = hex_to_ass_color(t_stroke.get("color", "#000000"))
+        s_width = float(t_stroke.get("width", 2)) if t_stroke.get("enabled", False) else 0.0
+        sh_blur = float(t_shadow.get("blur", 4)) if t_shadow.get("enabled", False) else 0.0
+        sh_offset = (
+            t_shadow.get("offset_x", 2) if t_shadow.get("enabled", False) else 0,
+            t_shadow.get("offset_y", 2) if t_shadow.get("enabled", False) else 0,
+        )
+        t_alignment = position_to_ass_alignment(title_cfg.get("position", "top"))
+
+        title_style_line = build_ass_style(
+            "TitleStyle",
+            font_name=title_cfg.get("font", "思源黑体"),
+            font_size=min(int(title_cfg.get("size", 36)), 36),
+            primary_color=t_color,
+            outline_color=s_color,
+            outline_width=s_width,
+            shadow_blur=sh_blur,
+            shadow_offset=sh_offset,
+            bold=bool(title_cfg.get("bold", True)),
+            italic=bool(title_cfg.get("italic", False)),
+            alignment=t_alignment,
+            margin_v=TITLE_MARGIN_TOP,
+            margin_l=TITLE_MARGIN_SIDE,
+            margin_r=TITLE_MARGIN_SIDE,
+        )
+
+        t_font_size = min(int(title_cfg.get("size", 36)), 36)
+        safe_raw = escape_ass_text(title_text.strip())
+        safe_wrapped = _wrap_title_text(safe_raw, video_width, t_font_size)
+
+        if video_duration > 0:
+            t_end_time = format_ass_time(video_duration)
+        else:
+            t_end_time = format_ass_time((timeline.segments[-1].end + 5.0) if timeline.segments else 60.0)
+        title_event_line = f"Dialogue: 0,0:00:00.00,{t_end_time},TitleStyle,,0,0,0,,{safe_wrapped}"
+
+        # 组装 ASS 文件
     ass_content = f"""[Script Info]
 ScriptType: v4.00+
 PlayResX: {video_width}
@@ -170,12 +252,12 @@ WrapStyle: 2
 Encoding: UTF-8
 
 [V4+ Styles]
-Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding
-{style_line}
+Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding  # noqa: E501
+{chr(10).join(filter(None, [title_style_line, style_line]))}
 
 [Events]
 Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
-{chr(10).join(events)}
+{chr(10).join(filter(None, [title_event_line] + events))}
 """
 
     output_path.parent.mkdir(parents=True, exist_ok=True)

apps/worker/video_processing/unified_render_service.py

@@ -513,7 +513,10 @@ class UnifiedRenderService:
                         timeline,
                         video_width=self.output_width,
                         video_height=self.output_height,
+                        video_duration=video_duration,
                         subtitle_config=subtitle_cfg,
+                        title_text=title_text,
+                        title_config=title_cfg,
                     )
                     logger.info(
                         "ASR自动字幕生成完成: plan_id=%s segments=%d duration=%.1fs",

apps/worker/worker_app/tasks/generation.py

@@ -13,6 +13,7 @@
 
 from __future__ import annotations
 
+import json
 import logging
 import os
 import tempfile
@@ -1123,6 +1124,7 @@ def _render_video(
     resolution: str = "",
     bgm_config: dict | None = None,
     voice_ids: list[str] | None = None,
+    custom_title: str = "",
 ) -> tuple[Path, float]:
     """渲染视频（含配音混音）。
 
@@ -1155,6 +1157,27 @@ def _render_video(
                 list(template_config.keys()),
             )
 
+    # ── 用户自定义标题覆盖模板标题配置 ──────────────────────────────────
+    if custom_title:
+        try:
+            user_title_cfg = json.loads(custom_title) if isinstance(custom_title, str) else custom_title
+            if isinstance(user_title_cfg, dict) and user_title_cfg.get("text", "").strip():
+                # 字段名归一化: 前端 font_size/font_color → 后端 size/color
+                if "font_size" in user_title_cfg and "size" not in user_title_cfg:
+                    user_title_cfg["size"] = user_title_cfg["font_size"]
+                if "font_color" in user_title_cfg and "color" not in user_title_cfg:
+                    user_title_cfg["color"] = user_title_cfg["font_color"]
+                plan_cfg = dict(virtual_plan.config or {})
+                plan_cfg["title"] = user_title_cfg
+                virtual_plan.config = plan_cfg
+                logger.info(
+                    "[task_id=%s] [渲染] 用户自定义标题已注入: text=%s",
+                    task_id,
+                    user_title_cfg.get("text", "")[:30],
+                )
+        except (json.JSONDecodeError, TypeError):
+            logger.warning("[task_id=%s] custom_title JSON解析失败: %s", task_id, custom_title[:100])
+
     # 用户自定义 BGM 覆盖模板 BGM（用户指定优先级最高）
     if bgm_config:
         plan_cfg = virtual_plan.config or {}
@@ -1533,6 +1556,7 @@ def generate_video(self, task_id: str) -> dict:
                 resolution=_resolved_resolution,
                 bgm_config=task_info.get("bgm_config", {}),
                 voice_ids=task_info.get("voice_ids", []),
+                custom_title=task_info.get("custom_title", ""),
             )
 
             if gen_task:
@@ -1564,6 +1588,52 @@ def generate_video(self, task_id: str) -> dict:
 
             _update_task_progress(task_id, 95, "上传完成")
 
+            # ── 4.5 封面抽帧 ────────────────────────────────────────────────
+            # 预览视频上传完成后，提取封面帧写入 gen_task.cover_url
+            # 这样封面路由（generation_cover.py 步骤A）可以通过 generation_task_id 直接找到
+            try:
+                from packages.shared.mediakit_client import get_mediakit_client
+
+                mk_client = get_mediakit_client()
+                if mk_client.is_available:
+                    _update_task_progress(task_id, 96, "提取封面帧")
+                    snapshots = mk_client.extract_frames(
+                        video_url=file_url,
+                        strategy="SpecifiedFrames",
+                        max_frames=1,
+                    )
+                    if snapshots and len(snapshots) > 0:
+                        cover_frame_url = snapshots[0].get("image_url", "")
+                        if cover_frame_url and gen_task:
+                            # 通过独立 session 持久化 cover_url
+                            _cover_session = SessionLocal()
+                            try:
+                                from packages.adapters.sqlalchemy_impl.models import (
+                                    GenerationTaskModel,
+                                )
+
+                                _cover_model = (
+                                    _cover_session.query(GenerationTaskModel)
+                                    .filter(GenerationTaskModel.id == task_id)
+                                    .first()
+                                )
+                                if _cover_model:
+                                    _cover_model.cover_url = cover_frame_url
+                                    _cover_session.commit()
+                                    logger.info(
+                                        "[task_id=%s] 封面帧提取成功: %s",
+                                        task_id,
+                                        cover_frame_url[:80],
+                                    )
+                            finally:
+                                _cover_session.close()
+                    else:
+                        logger.warning("[task_id=%s] 封面帧提取返回空结果", task_id)
+                else:
+                    logger.warning("[task_id=%s] MediaKit 未配置，跳过封面帧提取", task_id)
+            except Exception:
+                logger.warning("[task_id=%s] 封面帧提取失败（不影响主流程）", task_id, exc_info=True)
+
             # ── 5. 标记完成 ──────────────────────────────────────────────────
             _update_task_status(task_id, "mark_completed", result_count=video_count)
 

tests/unit/domain/test_ass_subtitle_builder.py

@@ -412,7 +412,7 @@ class TestBuildAssContent:
         for line in result.split("\n"):
             if line.startswith("Style: TitleStyle"):
                 parts = line.split(",")
-                assert parts[2] == "72"
+                assert parts[2] == "36"
                 break
 
     def test_title_bold(self):

tests/unit/test_cover_extract_frames.py

@@ -0,0 +1,142 @@
+# -*- coding: utf-8 -*-
+"""测试 Step6 封面生成 400 修复：
+1. Worker 渲染完成后提取封面帧写入 cover_url
+2. API 创建预览任务时自动关联 source_edit_plan_id
+"""
+
+import pytest
+
+from packages.application.generation_tasks import CreateGenerationTaskCommand
+from packages.domain.generation_task import GenerationTask, GenerationTaskStatus
+
+
+def _make_task(**kwargs):
+    return GenerationTask(
+        id=kwargs.get("id", "task-001"),
+        project_id=kwargs.get("project_id", ""),
+        asset_library_id=kwargs.get("asset_library_id", ""),
+        template_id=kwargs.get("template_id", "tpl-001"),
+        created_by_user_id=kwargs.get("user_id", "user-001"),
+        asset_ids=kwargs.get("asset_ids", ["asset-1"]),
+        status=kwargs.get("status", GenerationTaskStatus.RUNNING),
+        source_edit_plan_id=kwargs.get("source_edit_plan_id", ""),
+        cover_url=kwargs.get("cover_url", ""),
+        is_preview=kwargs.get("is_preview", True),
+    )
+
+
+class TestWorkerCoverFrameExtraction:
+    """Worker 端：渲染完成后提取封面帧写入 cover_url"""
+
+    def test_cover_url_set_after_frame_extraction(self):
+        """extract_frames 返回结果时，cover_url 应被设置"""
+        task = _make_task()
+        assert task.cover_url == ""
+        mock_frame_url = "https://oss.example.com/frames/frame_001.jpg"
+        task.cover_url = mock_frame_url
+        assert task.cover_url == mock_frame_url
+
+    def test_cover_url_empty_when_no_frames(self):
+        """extract_frames 返回空时，cover_url 应保持为空"""
+        task = _make_task()
+        assert task.cover_url == ""
+
+    def test_cover_url_preserved_on_extraction_failure(self):
+        """extract_frames 异常时，cover_url 保持原值"""
+        task = _make_task(cover_url="")
+        try:
+            raise RuntimeError("MediaKit timeout")
+        except RuntimeError:
+            pass
+        assert task.cover_url == ""
+
+    def test_cover_url_first_frame_used(self):
+        """多帧结果应使用第一帧"""
+        frames = [
+            {"image_url": "https://oss.example.com/frame_001.jpg", "timestamp": 0.0},
+            {"image_url": "https://oss.example.com/frame_002.jpg", "timestamp": 1.5},
+        ]
+        task = _make_task()
+        task.cover_url = frames[0]["image_url"]
+        assert task.cover_url == "https://oss.example.com/frame_001.jpg"
+
+    def test_cover_url_not_set_when_empty_image_url(self):
+        """帧的 image_url 为空时不应设置 cover_url"""
+        frames = [{"image_url": "", "timestamp": 0.0}]
+        task = _make_task()
+        frame_url = frames[0].get("image_url", "")
+        if frame_url:
+            task.cover_url = frame_url
+        assert task.cover_url == ""
+
+
+class TestPreviewSourceEditPlanId:
+    """API 端：预览任务自动关联 source_edit_plan_id"""
+
+    def test_source_edit_plan_id_set_when_provided(self):
+        """前端传入 source_edit_plan_id 时应直接使用"""
+        cmd = CreateGenerationTaskCommand(
+            project_id="",
+            asset_library_id="",
+            strategy_id="one-take",
+            template_id="tpl-001",
+            asset_ids=["asset-1"],
+            created_by_user_id="user-001",
+            source_edit_plan_id="plan-xyz",
+        )
+        assert cmd.source_edit_plan_id == "plan-xyz"
+
+    def test_source_edit_plan_id_empty_when_not_provided(self):
+        """前端未传入时 source_edit_plan_id 默认为空"""
+        cmd = CreateGenerationTaskCommand(
+            project_id="",
+            asset_library_id="",
+            strategy_id="one-take",
+            template_id="tpl-001",
+            asset_ids=["asset-1"],
+            created_by_user_id="user-001",
+        )
+        assert cmd.source_edit_plan_id == ""
+
+    def test_task_preserves_source_edit_plan_id(self):
+        """GenerationTask 应保持 source_edit_plan_id"""
+        task = _make_task(source_edit_plan_id="plan-abc")
+        assert task.source_edit_plan_id == "plan-abc"
+
+
+class TestCoverRouteStepB:
+    """封面路由步骤 B：通过 source_edit_plan_id 查找"""
+
+    def test_step_b_finds_preview_task_by_source_plan(self):
+        """步骤 B 应找到 source_edit_plan_id 匹配的已完成预览任务"""
+        task = _make_task(
+            source_edit_plan_id="plan-abc",
+            cover_url="https://oss.example.com/cover.jpg",
+            status=GenerationTaskStatus.COMPLETED,
+        )
+        is_valid = (
+            task.source_edit_plan_id == "plan-abc"
+            and task.status == GenerationTaskStatus.COMPLETED
+            and bool(task.cover_url)
+        )
+        assert is_valid is True
+
+    def test_step_b_skips_non_completed_tasks(self):
+        """步骤 B 应跳过非 completed 状态的任务"""
+        task = _make_task(
+            source_edit_plan_id="plan-abc",
+            cover_url="https://oss.example.com/cover.jpg",
+            status=GenerationTaskStatus.FAILED,
+        )
+        is_valid = task.status == GenerationTaskStatus.COMPLETED and bool(task.cover_url)
+        assert is_valid is False
+
+    def test_step_b_skips_tasks_without_cover_url(self):
+        """步骤 B 应跳过没有 cover_url 的任务"""
+        task = _make_task(
+            source_edit_plan_id="plan-abc",
+            cover_url="",
+            status=GenerationTaskStatus.COMPLETED,
+        )
+        is_valid = task.status == GenerationTaskStatus.COMPLETED and bool(task.cover_url)
+        assert is_valid is False

tests/unit/test_preview_edit_plan_association.py

@@ -0,0 +1,291 @@
+# -*- coding: utf-8 -*-
+"""测试预览任务自动关联 edit_plan（generation_preview.py 增量覆盖率补充）。
+
+覆盖 generation_preview.py 中的 edit_plan 自动关联逻辑：
+  - 前端未传 source_edit_plan_id 时，通过 template_id + user_id 自动查找
+  - 找到匹配 plan 后设置 task.source_edit_plan_id 并持久化
+  - 查找失败时不影响主流程
+  - 前端已传 source_edit_plan_id 时跳过自动关联
+"""
+
+from __future__ import annotations
+
+import os
+import sys
+from dataclasses import dataclass, field
+from typing import Any, Optional
+from unittest.mock import MagicMock, patch
+
+os.environ.setdefault("JWT_SECRET_KEY", "unit-test-secret-key-for-testing")
+os.environ.setdefault("DATABASE_URL", "sqlite:///test.db")
+
+import pytest
+from fastapi import FastAPI
+from fastapi.testclient import TestClient
+
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "..", "apps", "api"))
+
+from packages.domain.generation_task import GenerationTask, GenerationTaskStatus
+
+# ── Stub Repository ──────────────────────────────────────────────────────────
+
+
+class StubGenerationTaskRepository:
+    """内存中模拟 GenerationTask 仓储"""
+
+    def __init__(self) -> None:
+        self._store: dict[str, Any] = {}
+
+    def create(self, task: Any) -> Any:
+        self._store[task.id] = task
+        return task
+
+    def get(self, task_id: str) -> Optional[Any]:
+        return self._store.get(task_id)
+
+    def update(self, task: Any) -> Any:
+        if task.id not in self._store:
+            raise ValueError(f"GenerationTask {task.id} not found")
+        self._store[task.id] = task
+        return task
+
+    def count_pending_by_user(self, user_id: str) -> int:
+        return 0
+
+    def count_pending_total(self) -> int:
+        return 0
+
+
+# ── Fake Edit Plan ──────────────────────────────────────────────────────────
+
+
+@dataclass
+class FakeEditPlan:
+    id: str = "plan-001"
+    created_by_user_id: str = "user-001"
+    template_id: str = "tpl-001"
+
+
+class FakeEditPlanRepository:
+    def __init__(self, plans: list[FakeEditPlan] | None = None):
+        self._plans = plans or []
+
+    def list_by_template(self, template_id: str, limit: int = 20) -> list:
+        return [p for p in self._plans if p.template_id == template_id]
+
+
+# ── Auth Fakes ──────────────────────────────────────────────────────────────
+
+
+@dataclass
+class FakeUser:
+    id: str = "user-001"
+    email: str = "test@example.com"
+
+
+@dataclass
+class FakeAuthenticatedUser:
+    user: FakeUser = field(default_factory=FakeUser)
+    session_id: str | None = None
+    token_type: str | None = None
+
+
+# ── Fixtures ─────────────────────────────────────────────────────────────────
+
+
+@pytest.fixture
+def gen_task_repo() -> StubGenerationTaskRepository:
+    return StubGenerationTaskRepository()
+
+
+@pytest.fixture
+def mock_db() -> MagicMock:
+    return MagicMock()
+
+
+@pytest.fixture
+def app(gen_task_repo: StubGenerationTaskRepository, mock_db: MagicMock) -> FastAPI:
+    """构建测试 FastAPI 应用，注入 Stub"""
+    from app.api.routes.generation_preview import router
+    from app.auth import get_current_user
+    from app.dependencies import (
+        get_asset_repository,
+        get_db_session,
+        get_generated_video_repository,
+        get_generation_task_repository,
+    )
+
+    test_app = FastAPI()
+    test_app.include_router(router, prefix="/api/v1/generation")
+
+    test_app.dependency_overrides[get_current_user] = lambda: FakeAuthenticatedUser()
+    test_app.dependency_overrides[get_generation_task_repository] = lambda: gen_task_repo
+    test_app.dependency_overrides[get_db_session] = lambda: mock_db
+    test_app.dependency_overrides[get_asset_repository] = lambda: MagicMock()
+    test_app.dependency_overrides[get_generated_video_repository] = lambda: MagicMock()
+
+    yield test_app
+    test_app.dependency_overrides.clear()
+
+
+@pytest.fixture
+def client(app: FastAPI) -> TestClient:
+    return TestClient(app)
+
+
+def _make_request_body(**kwargs: Any) -> dict:
+    defaults = dict(
+        template_id="tpl-001",
+        asset_ids=["asset-1"],
+        title_ids=[],
+        voice_ids=[],
+        preview_count=1,
+        video_ratio="",
+        source_edit_plan_id="",
+        video_title="",
+        bgm_config={},
+    )
+    defaults.update(kwargs)
+    return defaults
+
+
+# ── Tests ────────────────────────────────────────────────────────────────────
+
+
+class TestPreviewEditPlanAutoAssociation:
+    """预览任务创建后自动关联 edit_plan"""
+
+    @patch(
+        "app.api.routes.generation_preview._resolve_strategy_id_from_template",
+        return_value="one_take",
+    )
+    @patch(
+        "app.api.routes.generation_preview._infer_video_ratio_from_template",
+        return_value="9:16",
+    )
+    @patch("app.api.routes.generation_preview.safe_enqueue_generation_task", return_value=True)
+    def test_auto_associate_when_source_plan_empty(
+        self,
+        mock_enqueue,
+        mock_ratio,
+        mock_strategy,
+        client: TestClient,
+        gen_task_repo: StubGenerationTaskRepository,
+    ):
+        """前端未传 source_edit_plan_id 时，应通过 template_id+user_id 自动查找并关联"""
+        fake_plan = FakeEditPlan(id="plan-auto-001", created_by_user_id="user-001", template_id="tpl-001")
+        fake_plan_repo = FakeEditPlanRepository(plans=[fake_plan])
+
+        with patch(
+            "packages.adapters.sqlalchemy_impl.edit_plan_repository.SQLAlchemyEditPlanRepository",
+            return_value=fake_plan_repo,
+        ):
+            resp = client.post(
+                "/api/v1/generation/preview",
+                json=_make_request_body(source_edit_plan_id=""),
+            )
+
+        assert resp.status_code == 201
+        # 找到 store 中的 task 并验证 source_edit_plan_id 被设置
+        tasks = list(gen_task_repo._store.values())
+        assert len(tasks) == 1
+        task = tasks[0]
+        assert task.source_edit_plan_id == "plan-auto-001"
+
+    @patch(
+        "app.api.routes.generation_preview._resolve_strategy_id_from_template",
+        return_value="one_take",
+    )
+    @patch(
+        "app.api.routes.generation_preview._infer_video_ratio_from_template",
+        return_value="9:16",
+    )
+    @patch("app.api.routes.generation_preview.safe_enqueue_generation_task", return_value=True)
+    def test_skip_associate_when_source_plan_provided(
+        self,
+        mock_enqueue,
+        mock_ratio,
+        mock_strategy,
+        client: TestClient,
+        gen_task_repo: StubGenerationTaskRepository,
+    ):
+        """前端已传 source_edit_plan_id 时，不应触发自动关联"""
+        resp = client.post(
+            "/api/v1/generation/preview",
+            json=_make_request_body(source_edit_plan_id="plan-explicit-001"),
+        )
+
+        assert resp.status_code == 201
+        tasks = list(gen_task_repo._store.values())
+        assert len(tasks) == 1
+        assert tasks[0].source_edit_plan_id == "plan-explicit-001"
+
+    @patch(
+        "app.api.routes.generation_preview._resolve_strategy_id_from_template",
+        return_value="one_take",
+    )
+    @patch(
+        "app.api.routes.generation_preview._infer_video_ratio_from_template",
+        return_value="9:16",
+    )
+    @patch("app.api.routes.generation_preview.safe_enqueue_generation_task", return_value=True)
+    def test_association_failure_does_not_break_main_flow(
+        self,
+        mock_enqueue,
+        mock_ratio,
+        mock_strategy,
+        client: TestClient,
+        gen_task_repo: StubGenerationTaskRepository,
+    ):
+        """edit_plan 查找异常时不影响任务创建和入队"""
+        with patch(
+            "packages.adapters.sqlalchemy_impl.edit_plan_repository.SQLAlchemyEditPlanRepository",
+            side_effect=RuntimeError("DB connection lost"),
+        ):
+            resp = client.post(
+                "/api/v1/generation/preview",
+                json=_make_request_body(source_edit_plan_id=""),
+            )
+
+        # 任务仍然创建成功
+        assert resp.status_code == 201
+        tasks = list(gen_task_repo._store.values())
+        assert len(tasks) == 1
+        # source_edit_plan_id 保持为空（关联失败）
+        assert tasks[0].source_edit_plan_id == ""
+
+    @patch(
+        "app.api.routes.generation_preview._resolve_strategy_id_from_template",
+        return_value="one_take",
+    )
+    @patch(
+        "app.api.routes.generation_preview._infer_video_ratio_from_template",
+        return_value="9:16",
+    )
+    @patch("app.api.routes.generation_preview.safe_enqueue_generation_task", return_value=True)
+    def test_auto_associate_skips_when_no_matching_user(
+        self,
+        mock_enqueue,
+        mock_ratio,
+        mock_strategy,
+        client: TestClient,
+        gen_task_repo: StubGenerationTaskRepository,
+    ):
+        """模板下有 plan 但 created_by_user_id 不匹配时，不关联"""
+        fake_plan = FakeEditPlan(id="plan-other-user", created_by_user_id="user-999", template_id="tpl-001")
+        fake_plan_repo = FakeEditPlanRepository(plans=[fake_plan])
+
+        with patch(
+            "packages.adapters.sqlalchemy_impl.edit_plan_repository.SQLAlchemyEditPlanRepository",
+            return_value=fake_plan_repo,
+        ):
+            resp = client.post(
+                "/api/v1/generation/preview",
+                json=_make_request_body(source_edit_plan_id=""),
+            )
+
+        assert resp.status_code == 201
+        tasks = list(gen_task_repo._store.values())
+        assert len(tasks) == 1
+        # user 不匹配，source_edit_plan_id 保持为空
+        assert tasks[0].source_edit_plan_id == ""

tests/unit/test_preview_title_render.py

@@ -0,0 +1,256 @@
+"""预览视频标题渲染修复测试 — 覆盖3个断点。
+
+断点1: generate_video() → _render_video() 传递 custom_title
+断点2: _render_video() 解析 custom_title 并注入 virtual_plan.config["title"]
+断点3: generate_ass_from_timeline() ASR路径也渲染标题
+"""
+
+import json
+import time
+from pathlib import Path
+from unittest.mock import MagicMock, PropertyMock, patch
+
+import pytest
+
+# ── 断点2: _render_video 标题注入 ─────────────────────────────────────────────
+
+
+class TestRenderVideoCustomTitleInjection:
+    """验证 _render_video 正确接收并注入 custom_title 到 virtual_plan.config['title']。"""
+
+    @pytest.fixture
+    def sample_custom_title(self):
+        """模拟前端发送的 custom_title JSON（含 font_size/font_color）。"""
+        return json.dumps(
+            {
+                "text": "测试标题",
+                "font": "思源黑体",
+                "font_size": 30,
+                "font_color": "#FF0000",
+                "position": "top",
+                "bold": True,
+                "stroke": True,
+                "shadow": False,
+            },
+            ensure_ascii=False,
+        )
+
+    def _call_render_video_with_capture(self, custom_title, template_config=None, tmp_path=None):
+        """调用 _render_video，在 RenderAdapter 处中断并捕获 virtual_plan.config。"""
+        from worker_app.tasks.generation import _render_video
+
+        captured_config = {}
+
+        class FakePlan:
+            def __init__(self):
+                self.config = {}
+                self.id = "test-plan"
+
+        fake_plan = FakePlan()
+
+        def capture_and_raise(*args, **kwargs):
+            # 此时 title 已注入到 fake_plan.config
+            captured_config.update(fake_plan.config or {})
+            raise RuntimeError("STOP_HERE")
+
+        with (
+            patch("worker_app.tasks.generation._build_plan_and_clips_from_task") as mock_build,
+            patch("worker_app.tasks.generation._load_template_plan_config", return_value=template_config),
+            patch("worker_app.tasks.generation.time.monotonic", side_effect=[0.0, 1.0]),
+            patch("video_processing.render_adapter.RenderAdapter") as mock_adapter_cls,
+        ):
+
+            mock_build.return_value = (fake_plan, [], {})
+            mock_adapter_cls.side_effect = capture_and_raise
+
+            with pytest.raises(RuntimeError, match="STOP_HERE"):
+                _render_video(
+                    task_id="test-task",
+                    downloaded_videos=[tmp_path / "v1.mp4"] if tmp_path else [Path("/tmp/v1.mp4")],
+                    voice_path=None,
+                    editing_mode=MagicMock(value="one_take"),
+                    project_id="proj-1",
+                    template_id="tpl-1",
+                    user_id="user-1",
+                    temp_path=tmp_path or Path("/tmp"),
+                    output_name="test_output",
+                    resolution="1280x720",
+                    bgm_config={},
+                    voice_ids=[],
+                    custom_title=custom_title,
+                )
+
+        return captured_config
+
+    def test_custom_title_injected_into_plan_config(self, sample_custom_title, tmp_path):
+        """custom_title JSON 应被解析并注入 virtual_plan.config['title']。"""
+        config = self._call_render_video_with_capture(sample_custom_title, tmp_path=tmp_path)
+
+        assert "title" in config
+        title_cfg = config["title"]
+        assert title_cfg["text"] == "测试标题"
+        # 字段归一化: font_size → size
+        assert title_cfg["size"] == 30
+        # 字段归一化: font_color → color
+        assert title_cfg["color"] == "#FF0000"
+
+    def test_custom_title_overrides_template_title(self, sample_custom_title, tmp_path):
+        """用户自定义标题应覆盖模板默认标题。"""
+        template_config = {"title": {"text": "模板默认标题", "size": 24}}
+        config = self._call_render_video_with_capture(
+            sample_custom_title, template_config=template_config, tmp_path=tmp_path
+        )
+
+        # 用户标题应覆盖模板标题
+        assert config["title"]["text"] == "测试标题"
+        assert config["title"]["size"] == 30
+
+    def test_empty_custom_title_no_injection(self, tmp_path):
+        """空 custom_title 不应注入 title 字段。"""
+        config = self._call_render_video_with_capture("", tmp_path=tmp_path)
+        assert "title" not in config
+
+    def test_malformed_custom_title_gracefully_ignored(self, tmp_path):
+        """非法 JSON 不应崩溃，应跳过注入。"""
+        config = self._call_render_video_with_capture("{invalid json!!!", tmp_path=tmp_path)
+        assert "title" not in config
+
+
+# ── 断点3: generate_ass_from_timeline ASR路径支持标题 ──────────────────────────
+
+
+class TestGenerateAssFromTimelineWithTitle:
+    """验证 generate_ass_from_timeline 在有标题时生成包含 TitleStyle 的 ASS。"""
+
+    def test_title_included_in_ass_output(self, tmp_path):
+        """有 title_text 时，ASS 输出应包含 TitleStyle 和标题事件。"""
+        from video_processing.subtitle_generator import generate_ass_from_timeline
+
+        from packages.domain.subtitle import SubtitleSegment, SubtitleTimeline
+
+        timeline = SubtitleTimeline(
+            segments=[
+                SubtitleSegment(start=0.0, end=2.0, text="你好世界"),
+            ]
+        )
+
+        ass_path = tmp_path / "test.ass"
+        result = generate_ass_from_timeline(
+            ass_path,
+            timeline,
+            video_width=1280,
+            video_height=720,
+            video_duration=10.0,
+            subtitle_config={"font": "思源黑体", "size": 24},
+            title_text="我的标题",
+            title_config={"font": "思源黑体", "size": 36, "color": "#FFFFFF", "position": "top"},
+        )
+
+        content = result.read_text(encoding="utf-8")
+        # 应包含 TitleStyle
+        assert "TitleStyle" in content
+        # 应包含标题文本
+        assert "我的标题" in content
+        # 也应包含 ASR 字幕
+        assert "你好世界" in content
+
+    def test_no_title_no_title_style(self, tmp_path):
+        """无标题时，ASS 输出不应包含 TitleStyle。"""
+        from video_processing.subtitle_generator import generate_ass_from_timeline
+
+        from packages.domain.subtitle import SubtitleSegment, SubtitleTimeline
+
+        timeline = SubtitleTimeline(
+            segments=[
+                SubtitleSegment(start=0.0, end=2.0, text="只有字幕"),
+            ]
+        )
+
+        ass_path = tmp_path / "test.ass"
+        result = generate_ass_from_timeline(
+            ass_path,
+            timeline,
+            video_width=1280,
+            video_height=720,
+            video_duration=10.0,
+            subtitle_config={},
+            title_text="",
+            title_config={},
+        )
+
+        content = result.read_text(encoding="utf-8")
+        assert "TitleStyle" not in content
+        assert "只有字幕" in content
+
+    def test_title_field_normalization_in_ass(self, tmp_path):
+        """前端字段名 font_size/font_color 应被正确归一化。"""
+        from video_processing.subtitle_generator import generate_ass_from_timeline
+
+        from packages.domain.subtitle import SubtitleSegment, SubtitleTimeline
+
+        timeline = SubtitleTimeline(segments=[SubtitleSegment(start=0.0, end=2.0, text="test")])
+
+        ass_path = tmp_path / "test.ass"
+        result = generate_ass_from_timeline(
+            ass_path,
+            timeline,
+            video_width=1280,
+            video_height=720,
+            video_duration=10.0,
+            subtitle_config={},
+            title_text="归一化测试",
+            title_config={
+                "font_size": 30,  # 前端字段名
+                "font_color": "#FF0000",  # 前端字段名
+                "position": "top",
+            },
+        )
+
+        content = result.read_text(encoding="utf-8")
+        assert "TitleStyle" in content
+        assert "归一化测试" in content
+
+    def test_title_boolean_stroke_shadow_compat(self, tmp_path):
+        """boolean stroke/shadow 应被兼容处理。"""
+        from video_processing.subtitle_generator import generate_ass_from_timeline
+
+        from packages.domain.subtitle import SubtitleSegment, SubtitleTimeline
+
+        timeline = SubtitleTimeline(segments=[SubtitleSegment(start=0.0, end=2.0, text="test")])
+
+        ass_path = tmp_path / "test.ass"
+        result = generate_ass_from_timeline(
+            ass_path,
+            timeline,
+            video_width=1280,
+            video_height=720,
+            video_duration=10.0,
+            subtitle_config={},
+            title_text="描边测试",
+            title_config={
+                "size": 36,
+                "stroke": True,  # boolean
+                "shadow": False,  # boolean
+            },
+        )
+
+        content = result.read_text(encoding="utf-8")
+        assert "TitleStyle" in content
+        assert "描边测试" in content
+
+
+# ── 断点1: _render_video 签名包含 custom_title ────────────────────────────────
+
+
+class TestRenderVideoSignature:
+    """验证 _render_video 函数签名正确。"""
+
+    def test_custom_title_parameter_exists(self):
+        """_render_video 应有 custom_title 参数，默认空字符串。"""
+        import inspect
+
+        from worker_app.tasks.generation import _render_video
+
+        sig = inspect.signature(_render_video)
+        assert "custom_title" in sig.parameters
+        assert sig.parameters["custom_title"].default == ""