"""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, ""