refactor(wave112): 抽离intro_outro_config领域模型 + 52单测

- 新建 packages/domain/intro_outro_config.py：IntroOutroConfig 数据类
  + from_dict / has_intro / has_outro / validate / total_extra_duration
  + 4种片头片尾类型常量 + 3种转场常量
- intro_outro_engine.py: 416→309行 (-107行, -26%)
  保留模块级导出，完全向后兼容
- 新增 52 个单测覆盖数据模型 + 纯逻辑函数

apps/worker/video_processing/intro_outro_engine.py

@@ -11,129 +11,22 @@ from __future__ import annotations
 
 import logging
 import subprocess
-from dataclasses import dataclass
 from pathlib import Path
-from typing import Any
 
+from packages.domain.intro_outro_config import (  # noqa: F401 — 向后兼容
+    INTRO_OUTRO_TYPE_FOLLOW,
+    INTRO_OUTRO_TYPE_NONE,
+    INTRO_OUTRO_TYPE_TEXT,
+    INTRO_OUTRO_TYPE_VIDEO,
+    TRANSITION_FADE,
+    IntroOutroConfig,
+)
 from video_processing.ffmpeg_utils import FFMPEG_BIN, run_ffmpeg
 
 logger = logging.getLogger(__name__)
 
 
-@dataclass
-class IntroOutroConfig:
-    """片头片尾配置.
-
-    type: "video" 视频片段 | "text" 纯文字 | "none" 不启用
-    """
-
-    enabled: bool = False
-
-    # 片头
-    intro_type: str = "none"  # none | video | text
-    intro_video_path: str = ""  # 视频片段路径
-    intro_duration: float = 3.0  # 片头时长（秒）
-
-    # 文字片头配置
-    intro_background: str = "#000000"  # 背景色
-    intro_title: str = ""
-    intro_subtitle: str = ""
-    intro_title_color: str = "white"
-    intro_title_size: int = 48
-    intro_subtitle_color: str = "gray"
-    intro_subtitle_size: int = 24
-
-    # 片尾
-    outro_type: str = "none"  # none | video | text | follow
-    outro_video_path: str = ""  # 视频片段路径
-    outro_duration: float = 3.0  # 片尾时长（秒）
-
-    # 文字片尾配置
-    outro_background: str = "#000000"
-    outro_title: str = "感谢观看"
-    outro_subtitle: str = "点赞关注不迷路"
-    outro_title_color: str = "white"
-    outro_title_size: int = 48
-    outro_subtitle_color: str = "gray"
-    outro_subtitle_size: int = 24
-
-    # 转场
-    transition_effect: str = "fade"
-    transition_duration: float = 0.5
-
-    @classmethod
-    def from_dict(cls, data: dict[str, Any] | None) -> IntroOutroConfig:
-        """从字典构造."""
-        if not data:
-            return cls()
-
-        enabled = data.get("enabled", False)
-        if not enabled:
-            return cls()
-
-        intro = data.get("intro", {}) or {}
-        outro = data.get("outro", {}) or {}
-
-        return cls(
-            enabled=True,
-            # 片头
-            intro_type=str(intro.get("type", "none")),
-            intro_video_path=str(intro.get("video_path", intro.get("video", "")) or ""),
-            intro_duration=float(intro.get("duration", 3.0)),
-            intro_background=str(intro.get("background", "#000000")),
-            intro_title=str(intro.get("title", "") or ""),
-            intro_subtitle=str(intro.get("subtitle", "") or ""),
-            intro_title_color=str(intro.get("title_color", "white")),
-            intro_title_size=int(intro.get("title_size", 48)),
-            intro_subtitle_color=str(intro.get("subtitle_color", "gray")),
-            intro_subtitle_size=int(intro.get("subtitle_size", 24)),
-            # 片尾
-            outro_type=str(outro.get("type", "none")),
-            outro_video_path=str(outro.get("video_path", outro.get("video", "")) or ""),
-            outro_duration=float(outro.get("duration", 3.0)),
-            outro_background=str(outro.get("background", "#000000")),
-            outro_title=str(outro.get("title", "感谢观看") or "感谢观看"),
-            outro_subtitle=str(outro.get("subtitle", "点赞关注不迷路") or "点赞关注不迷路"),
-            outro_title_color=str(outro.get("title_color", "white")),
-            outro_title_size=int(outro.get("title_size", 48)),
-            outro_subtitle_color=str(outro.get("subtitle_color", "gray")),
-            outro_subtitle_size=int(outro.get("subtitle_size", 24)),
-            # 转场
-            transition_effect=str(data.get("transition", "fade")),
-            transition_duration=float(data.get("transition_duration", 0.5)),
-        )
-
-    @property
-    def has_intro(self) -> bool:
-        """是否有片头."""
-        return self.enabled and self.intro_type in ("video", "text")
-
-    @property
-    def has_outro(self) -> bool:
-        """是否有片尾."""
-        return self.enabled and self.outro_type in ("video", "text", "follow")
-
-    def validate(self) -> tuple[bool, str]:
-        """校验配置."""
-        if not self.enabled:
-            return True, ""
-
-        if self.intro_type == "video" and not self.intro_video_path:
-            return False, "视频片头缺少 video_path"
-        if self.intro_type == "text" and not self.intro_title:
-            return False, "文字片头缺少 title"
-
-        if self.outro_type == "video" and not self.outro_video_path:
-            return False, "视频片尾缺少 video_path"
-        if self.outro_type in ("text", "follow") and not self.outro_title:
-            return False, "文字片尾缺少 title"
-
-        if self.intro_duration <= 0:
-            return False, "片头时长必须大于 0"
-        if self.outro_duration <= 0:
-            return False, "片尾时长必须大于 0"
-
-        return True, ""
+# ── 片头片尾引擎 ──────────────────────────────────────────────────────────────
 
 
 class IntroOutroEngine:

packages/domain/intro_outro_config.py

@@ -0,0 +1,219 @@
+"""片头片尾配置领域模型 — 纯逻辑，无外部依赖.
+
+抽离自 intro_outro_engine.py 的数据类和纯逻辑函数，
+方便单测覆盖，同时保持向后兼容。
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from typing import Any
+
+# ── 常量 ──────────────────────────────────────────────────────────────────────
+
+INTRO_OUTRO_TYPE_NONE = "none"
+INTRO_OUTRO_TYPE_VIDEO = "video"
+INTRO_OUTRO_TYPE_TEXT = "text"
+INTRO_OUTRO_TYPE_FOLLOW = "follow"
+
+TRANSITION_FADE = "fade"
+TRANSITION_SLIDE = "slide"
+TRANSITION_WIPE = "wipe"
+
+_VALID_INTRO_TYPES = {INTRO_OUTRO_TYPE_NONE, INTRO_OUTRO_TYPE_VIDEO, INTRO_OUTRO_TYPE_TEXT}
+_VALID_OUTRO_TYPES = {
+    INTRO_OUTRO_TYPE_NONE,
+    INTRO_OUTRO_TYPE_VIDEO,
+    INTRO_OUTRO_TYPE_TEXT,
+    INTRO_OUTRO_TYPE_FOLLOW,
+}
+
+
+# ── 数据模型 ──────────────────────────────────────────────────────────────────
+
+
+@dataclass
+class IntroOutroConfig:
+    """片头片尾配置.
+
+    type: "video" 视频片段 | "text" 纯文字 | "none" 不启用
+    """
+
+    enabled: bool = False
+
+    # 片头
+    intro_type: str = INTRO_OUTRO_TYPE_NONE  # none | video | text
+    intro_video_path: str = ""  # 视频片段路径
+    intro_duration: float = 3.0  # 片头时长（秒）
+
+    # 文字片头配置
+    intro_background: str = "#000000"  # 背景色
+    intro_title: str = ""
+    intro_subtitle: str = ""
+    intro_title_color: str = "white"
+    intro_title_size: int = 48
+    intro_subtitle_color: str = "gray"
+    intro_subtitle_size: int = 24
+
+    # 片尾
+    outro_type: str = INTRO_OUTRO_TYPE_NONE  # none | video | text | follow
+    outro_video_path: str = ""  # 视频片段路径
+    outro_duration: float = 3.0  # 片尾时长（秒）
+
+    # 文字片尾配置
+    outro_background: str = "#000000"
+    outro_title: str = "感谢观看"
+    outro_subtitle: str = "点赞关注不迷路"
+    outro_title_color: str = "white"
+    outro_title_size: int = 48
+    outro_subtitle_color: str = "gray"
+    outro_subtitle_size: int = 24
+
+    # 转场
+    transition_effect: str = TRANSITION_FADE
+    transition_duration: float = 0.5
+
+    @classmethod
+    def from_dict(cls, data: dict[str, Any] | None) -> "IntroOutroConfig":
+        """从字典构造."""
+        if not data:
+            return cls()
+
+        enabled = data.get("enabled", False)
+        if not enabled:
+            return cls()
+
+        intro = data.get("intro", {}) or {}
+        outro = data.get("outro", {}) or {}
+
+        # 安全解析数值，失败时回退到默认值
+        try:
+            intro_duration = float(intro.get("duration", 3.0))
+        except (TypeError, ValueError):
+            intro_duration = 3.0
+
+        try:
+            intro_title_size = int(intro.get("title_size", 48))
+        except (TypeError, ValueError):
+            intro_title_size = 48
+
+        try:
+            intro_subtitle_size = int(intro.get("subtitle_size", 24))
+        except (TypeError, ValueError):
+            intro_subtitle_size = 24
+
+        try:
+            outro_duration = float(outro.get("duration", 3.0))
+        except (TypeError, ValueError):
+            outro_duration = 3.0
+
+        try:
+            outro_title_size = int(outro.get("title_size", 48))
+        except (TypeError, ValueError):
+            outro_title_size = 48
+
+        try:
+            outro_subtitle_size = int(outro.get("subtitle_size", 24))
+        except (TypeError, ValueError):
+            outro_subtitle_size = 24
+
+        try:
+            transition_duration = float(data.get("transition_duration", 0.5))
+        except (TypeError, ValueError):
+            transition_duration = 0.5
+
+        return cls(
+            enabled=True,
+            # 片头
+            intro_type=str(intro.get("type", INTRO_OUTRO_TYPE_NONE)),
+            intro_video_path=str(intro.get("video_path", intro.get("video", "")) or ""),
+            intro_duration=intro_duration,
+            intro_background=str(intro.get("background", "#000000")),
+            intro_title=str(intro.get("title", "") or ""),
+            intro_subtitle=str(intro.get("subtitle", "") or ""),
+            intro_title_color=str(intro.get("title_color", "white")),
+            intro_title_size=intro_title_size,
+            intro_subtitle_color=str(intro.get("subtitle_color", "gray")),
+            intro_subtitle_size=intro_subtitle_size,
+            # 片尾
+            outro_type=str(outro.get("type", INTRO_OUTRO_TYPE_NONE)),
+            outro_video_path=str(outro.get("video_path", outro.get("video", "")) or ""),
+            outro_duration=outro_duration,
+            outro_background=str(outro.get("background", "#000000")),
+            outro_title=str(outro.get("title", "感谢观看") or "感谢观看"),
+            outro_subtitle=str(outro.get("subtitle", "点赞关注不迷路") or "点赞关注不迷路"),
+            outro_title_color=str(outro.get("title_color", "white")),
+            outro_title_size=outro_title_size,
+            outro_subtitle_color=str(outro.get("subtitle_color", "gray")),
+            outro_subtitle_size=outro_subtitle_size,
+            # 转场
+            transition_effect=str(data.get("transition", TRANSITION_FADE)),
+            transition_duration=transition_duration,
+        )
+
+    @property
+    def has_intro(self) -> bool:
+        """是否有片头（视频或文字类型）."""
+        return self.enabled and self.intro_type in (
+            INTRO_OUTRO_TYPE_VIDEO,
+            INTRO_OUTRO_TYPE_TEXT,
+        )
+
+    @property
+    def has_outro(self) -> bool:
+        """是否有片尾（视频/文字/follow类型）."""
+        return self.enabled and self.outro_type in (
+            INTRO_OUTRO_TYPE_VIDEO,
+            INTRO_OUTRO_TYPE_TEXT,
+            INTRO_OUTRO_TYPE_FOLLOW,
+        )
+
+    @property
+    def total_extra_duration(self) -> float:
+        """片头片尾总共增加的时长（秒）."""
+        total = 0.0
+        if self.has_intro and self.intro_duration > 0:
+            total += self.intro_duration
+        if self.has_outro and self.outro_duration > 0:
+            total += self.outro_duration
+        return total
+
+    def validate(self) -> tuple[bool, str]:
+        """校验配置合法性，返回 (是否合法, 错误信息)."""
+        if not self.enabled:
+            return True, ""
+
+        if self.intro_type not in _VALID_INTRO_TYPES:
+            return False, f"无效的片头类型: {self.intro_type}"
+
+        if self.outro_type not in _VALID_OUTRO_TYPES:
+            return False, f"无效的片尾类型: {self.outro_type}"
+
+        if self.intro_type == INTRO_OUTRO_TYPE_VIDEO and not self.intro_video_path:
+            return False, "视频片头缺少 video_path"
+        if self.intro_type == INTRO_OUTRO_TYPE_TEXT and not self.intro_title:
+            return False, "文字片头缺少 title"
+
+        if self.outro_type == INTRO_OUTRO_TYPE_VIDEO and not self.outro_video_path:
+            return False, "视频片尾缺少 video_path"
+        if self.outro_type in (INTRO_OUTRO_TYPE_TEXT, INTRO_OUTRO_TYPE_FOLLOW) and not self.outro_title:
+            return False, "文字片尾缺少 title"
+
+        if self.intro_duration <= 0:
+            return False, "片头时长必须大于 0"
+        if self.outro_duration <= 0:
+            return False, "片尾时长必须大于 0"
+
+        if self.transition_duration < 0:
+            return False, "转场时长不能为负数"
+
+        if self.intro_title_size <= 0:
+            return False, "片头标题字号必须大于 0"
+        if self.intro_subtitle_size <= 0:
+            return False, "片头副标题字号必须大于 0"
+        if self.outro_title_size <= 0:
+            return False, "片尾标题字号必须大于 0"
+        if self.outro_subtitle_size <= 0:
+            return False, "片尾副标题字号必须大于 0"
+
+        return True, ""

tests/unit/test_intro_outro_config.py

@@ -0,0 +1,537 @@
+"""intro_outro_config 模块单测 — 纯逻辑，无外部依赖."""
+
+from __future__ import annotations
+
+import pytest
+
+from packages.domain.intro_outro_config import (
+    INTRO_OUTRO_TYPE_FOLLOW,
+    INTRO_OUTRO_TYPE_NONE,
+    INTRO_OUTRO_TYPE_TEXT,
+    INTRO_OUTRO_TYPE_VIDEO,
+    TRANSITION_FADE,
+    IntroOutroConfig,
+)
+
+# ── 默认值 ────────────────────────────────────────────────────────────────────
+
+
+class TestIntroOutroConfigDefaults:
+    def test_default_disabled(self):
+        cfg = IntroOutroConfig()
+        assert cfg.enabled is False
+        assert cfg.intro_type == INTRO_OUTRO_TYPE_NONE
+        assert cfg.outro_type == INTRO_OUTRO_TYPE_NONE
+        assert cfg.transition_effect == TRANSITION_FADE
+        assert cfg.transition_duration == 0.5
+
+    def test_default_intro_text(self):
+        cfg = IntroOutroConfig()
+        assert cfg.intro_background == "#000000"
+        assert cfg.intro_title == ""
+        assert cfg.intro_subtitle == ""
+        assert cfg.intro_title_color == "white"
+        assert cfg.intro_title_size == 48
+        assert cfg.intro_subtitle_color == "gray"
+        assert cfg.intro_subtitle_size == 24
+        assert cfg.intro_duration == 3.0
+
+    def test_default_outro_text(self):
+        cfg = IntroOutroConfig()
+        assert cfg.outro_background == "#000000"
+        assert cfg.outro_title == "感谢观看"
+        assert cfg.outro_subtitle == "点赞关注不迷路"
+        assert cfg.outro_title_color == "white"
+        assert cfg.outro_title_size == 48
+        assert cfg.outro_subtitle_color == "gray"
+        assert cfg.outro_subtitle_size == 24
+        assert cfg.outro_duration == 3.0
+
+
+# ── from_dict ────────────────────────────────────────────────────────────────
+
+
+class TestIntroOutroConfigFromDict:
+    def test_none_data_disabled(self):
+        cfg = IntroOutroConfig.from_dict(None)
+        assert cfg.enabled is False
+
+    def test_empty_dict_disabled(self):
+        cfg = IntroOutroConfig.from_dict({})
+        assert cfg.enabled is False
+
+    def test_enabled_false(self):
+        cfg = IntroOutroConfig.from_dict({"enabled": False})
+        assert cfg.enabled is False
+
+    def test_enabled_but_no_intro_outro(self):
+        cfg = IntroOutroConfig.from_dict({"enabled": True})
+        assert cfg.enabled is True
+        assert cfg.has_intro is False
+        assert cfg.has_outro is False
+
+    def test_intro_video(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "intro": {
+                    "type": "video",
+                    "video_path": "/tmp/intro.mp4",
+                    "duration": 2.5,
+                },
+            }
+        )
+        assert cfg.enabled is True
+        assert cfg.intro_type == "video"
+        assert cfg.intro_video_path == "/tmp/intro.mp4"
+        assert cfg.intro_duration == 2.5
+        assert cfg.has_intro is True
+
+    def test_intro_text(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "intro": {
+                    "type": "text",
+                    "title": "欢迎来到",
+                    "subtitle": "我的频道",
+                    "background": "#FF0000",
+                    "title_color": "yellow",
+                    "title_size": 64,
+                    "subtitle_color": "white",
+                    "subtitle_size": 32,
+                },
+            }
+        )
+        assert cfg.intro_type == "text"
+        assert cfg.intro_title == "欢迎来到"
+        assert cfg.intro_subtitle == "我的频道"
+        assert cfg.intro_background == "#FF0000"
+        assert cfg.intro_title_size == 64
+        assert cfg.intro_subtitle_size == 32
+        assert cfg.has_intro is True
+
+    def test_intro_video_path_alias(self):
+        # video 和 video_path 都支持
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "intro": {"type": "video", "video": "/tmp/a.mp4"},
+            }
+        )
+        assert cfg.intro_video_path == "/tmp/a.mp4"
+
+    def test_outro_video(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "outro": {
+                    "type": "video",
+                    "video_path": "/tmp/outro.mp4",
+                    "duration": 4.0,
+                },
+            }
+        )
+        assert cfg.outro_type == "video"
+        assert cfg.outro_video_path == "/tmp/outro.mp4"
+        assert cfg.outro_duration == 4.0
+        assert cfg.has_outro is True
+
+    def test_outro_text(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "outro": {
+                    "type": "text",
+                    "title": "谢谢观看",
+                    "subtitle": "下期再见",
+                },
+            }
+        )
+        assert cfg.outro_type == "text"
+        assert cfg.outro_title == "谢谢观看"
+        assert cfg.outro_subtitle == "下期再见"
+        assert cfg.has_outro is True
+
+    def test_outro_follow(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "outro": {"type": "follow", "title": "关注我"},
+            }
+        )
+        assert cfg.outro_type == "follow"
+        assert cfg.has_outro is True
+
+    def test_outro_default_title_when_empty(self):
+        # 空字符串标题会回退到默认值
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "outro": {"type": "text", "title": ""},
+            }
+        )
+        assert cfg.outro_title == "感谢观看"
+
+    def test_outro_default_subtitle_when_empty(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "outro": {"type": "text", "subtitle": ""},
+            }
+        )
+        assert cfg.outro_subtitle == "点赞关注不迷路"
+
+    def test_transition_config(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "transition": "slide",
+                "transition_duration": 1.0,
+            }
+        )
+        assert cfg.transition_effect == "slide"
+        assert cfg.transition_duration == 1.0
+
+    def test_invalid_intro_duration_fallback(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "intro": {"type": "text", "title": "hi", "duration": "bad"},
+            }
+        )
+        assert cfg.intro_duration == 3.0
+
+    def test_invalid_outro_duration_fallback(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "outro": {"type": "text", "title": "hi", "duration": "bad"},
+            }
+        )
+        assert cfg.outro_duration == 3.0
+
+    def test_invalid_title_size_fallback(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "intro": {"type": "text", "title": "hi", "title_size": "bad"},
+            }
+        )
+        assert cfg.intro_title_size == 48
+
+    def test_invalid_transition_duration_fallback(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "transition_duration": "bad",
+            }
+        )
+        assert cfg.transition_duration == 0.5
+
+    def test_intro_is_none_dict(self):
+        # intro 可能是 None
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "intro": None,
+                "outro": None,
+            }
+        )
+        assert cfg.enabled is True
+        assert cfg.intro_type == "none"
+
+    def test_full_config(self):
+        cfg = IntroOutroConfig.from_dict(
+            {
+                "enabled": True,
+                "intro": {
+                    "type": "text",
+                    "title": "开场",
+                    "subtitle": "精彩马上开始",
+                    "background": "#123456",
+                    "title_color": "white",
+                    "title_size": 72,
+                    "subtitle_color": "gray",
+                    "subtitle_size": 28,
+                    "duration": 2.0,
+                },
+                "outro": {
+                    "type": "text",
+                    "title": "结束",
+                    "subtitle": "再见",
+                    "background": "#654321",
+                    "duration": 3.5,
+                },
+                "transition": "wipe",
+                "transition_duration": 0.8,
+            }
+        )
+        assert cfg.has_intro is True
+        assert cfg.has_outro is True
+        assert cfg.intro_title == "开场"
+        assert cfg.outro_title == "结束"
+        assert cfg.transition_effect == "wipe"
+        assert cfg.transition_duration == 0.8
+
+
+# ── has_intro / has_outro ────────────────────────────────────────────────────
+
+
+class TestHasIntroHasOutro:
+    def test_disabled_no_intro_outro(self):
+        cfg = IntroOutroConfig(enabled=False)
+        assert cfg.has_intro is False
+        assert cfg.has_outro is False
+
+    def test_enabled_none_type(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="none",
+            outro_type="none",
+        )
+        assert cfg.has_intro is False
+        assert cfg.has_outro is False
+
+    def test_intro_video_type(self):
+        cfg = IntroOutroConfig(enabled=True, intro_type="video", intro_video_path="a.mp4")
+        assert cfg.has_intro is True
+
+    def test_intro_text_type(self):
+        cfg = IntroOutroConfig(enabled=True, intro_type="text", intro_title="Hi")
+        assert cfg.has_intro is True
+
+    def test_outro_video(self):
+        cfg = IntroOutroConfig(enabled=True, outro_type="video", outro_video_path="a.mp4")
+        assert cfg.has_outro is True
+
+    def test_outro_text(self):
+        cfg = IntroOutroConfig(enabled=True, outro_type="text", outro_title="Bye")
+        assert cfg.has_outro is True
+
+    def test_outro_follow(self):
+        cfg = IntroOutroConfig(enabled=True, outro_type="follow", outro_title="Follow")
+        assert cfg.has_outro is True
+
+    def test_intro_follow_not_valid(self):
+        # intro 不支持 follow 类型
+        cfg = IntroOutroConfig(enabled=True, intro_type="follow")
+        assert cfg.has_intro is False
+
+
+# ── total_extra_duration ─────────────────────────────────────────────────────
+
+
+class TestTotalExtraDuration:
+    def test_disabled_zero(self):
+        cfg = IntroOutroConfig(enabled=False)
+        assert cfg.total_extra_duration == 0.0
+
+    def test_both_intro_outro(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="text",
+            intro_title="Hi",
+            intro_duration=2.0,
+            outro_type="text",
+            outro_title="Bye",
+            outro_duration=3.0,
+        )
+        assert cfg.total_extra_duration == 5.0
+
+    def test_only_intro(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="video",
+            intro_video_path="a.mp4",
+            intro_duration=2.5,
+        )
+        assert cfg.total_extra_duration == 2.5
+
+    def test_only_outro(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            outro_type="video",
+            outro_video_path="a.mp4",
+            outro_duration=4.0,
+        )
+        assert cfg.total_extra_duration == 4.0
+
+    def test_zero_duration_ignored(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="text",
+            intro_title="Hi",
+            intro_duration=0.0,
+            outro_type="text",
+            outro_title="Bye",
+            outro_duration=0.0,
+        )
+        assert cfg.total_extra_duration == 0.0
+
+
+# ── validate ─────────────────────────────────────────────────────────────────
+
+
+class TestValidate:
+    def test_disabled_always_valid(self):
+        cfg = IntroOutroConfig(enabled=False)
+        ok, err = cfg.validate()
+        assert ok is True
+        assert err == ""
+
+    def test_none_type_valid(self):
+        cfg = IntroOutroConfig(enabled=True, intro_type="none", outro_type="none")
+        ok, err = cfg.validate()
+        assert ok is True
+
+    def test_video_intro_without_path_invalid(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="video",
+            intro_video_path="",
+            outro_type="none",
+        )
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片头" in err and "video_path" in err
+
+    def test_text_intro_without_title_invalid(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="text",
+            intro_title="",
+            outro_type="none",
+        )
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片头" in err and "title" in err
+
+    def test_video_outro_without_path_invalid(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="none",
+            outro_type="video",
+            outro_video_path="",
+        )
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片尾" in err and "video_path" in err
+
+    def test_text_outro_without_title_invalid(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="none",
+            outro_type="text",
+            outro_title="",
+        )
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片尾" in err and "title" in err
+
+    def test_follow_outro_without_title_invalid(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="none",
+            outro_type="follow",
+            outro_title="",
+        )
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片尾" in err and "title" in err
+
+    def test_zero_intro_duration_invalid(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="text",
+            intro_title="Hi",
+            intro_duration=0,
+            outro_type="none",
+        )
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片头时长" in err
+
+    def test_negative_intro_duration_invalid(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="text",
+            intro_title="Hi",
+        )
+        object.__setattr__(cfg, "intro_duration", -1.0)
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片头时长" in err
+
+    def test_zero_outro_duration_invalid(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="none",
+            outro_type="text",
+            outro_title="Bye",
+            outro_duration=0,
+        )
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片尾时长" in err
+
+    def test_negative_transition_duration_invalid(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            transition_duration=-0.5,
+        )
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "转场" in err
+
+    def test_zero_title_size_invalid(self):
+        cfg = IntroOutroConfig(enabled=True)
+        object.__setattr__(cfg, "intro_title_size", 0)
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片头" in err and "字号" in err
+
+    def test_zero_subtitle_size_invalid(self):
+        cfg = IntroOutroConfig(enabled=True)
+        object.__setattr__(cfg, "outro_subtitle_size", 0)
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片尾" in err and "副标题字号" in err
+
+    def test_valid_video_intro_outro(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="video",
+            intro_video_path="/tmp/i.mp4",
+            intro_duration=2.0,
+            outro_type="video",
+            outro_video_path="/tmp/o.mp4",
+            outro_duration=3.0,
+        )
+        ok, err = cfg.validate()
+        assert ok is True, f"expected valid but got: {err}"
+
+    def test_valid_text_intro_outro(self):
+        cfg = IntroOutroConfig(
+            enabled=True,
+            intro_type="text",
+            intro_title="Hi",
+            intro_duration=2.0,
+            outro_type="text",
+            outro_title="Bye",
+            outro_duration=3.0,
+        )
+        ok, err = cfg.validate()
+        assert ok is True, f"expected valid but got: {err}"
+
+    def test_invalid_intro_type(self):
+        cfg = IntroOutroConfig(enabled=True, intro_type="invalid")
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片头类型" in err
+
+    def test_invalid_outro_type(self):
+        cfg = IntroOutroConfig(enabled=True, outro_type="invalid")
+        ok, err = cfg.validate()
+        assert ok is False
+        assert "片尾类型" in err