"""
PregoPal - 核心循环引擎
=======================
状态机驱动的每日生命周期管理。

状态流转：
  LAUNCH → FAMILY_QUIZ → SUMMARIZE → ANALYZE → BRIEF → INTERACT
  → CONSOLIDATE → (THREE_DAY) → DONE

状态位机制：
  data/presets/.daily_status.json 记录每日完成状态
"""

import json
import datetime
import asyncio
from enum import Enum
from pathlib import Path
from dataclasses import dataclass, field

from plugins.base import LoopPlugin, PluginResult, PluginRegistry, LoopStage, LoopContext

PRESETS_DIR = Path("data/presets")
STATUS_FILE = PRESETS_DIR / ".daily_status.json"


# ============================================================
# 状态枚举
# ============================================================
class LoopState(Enum):
    LAUNCH = "launch"           # 启动检查：检查今日状态位
    FAMILY_QUIZ = "family_quiz" # 家庭问卷：检查是否需要询问菜谱/体重
    SUMMARIZE = "summarize"     # 昨日总结：分析昨日饮食/体重/家庭记忆
    ANALYZE = "analyze"         # 营养分析：对比 DRIs
    BRIEF = "brief"             # 生成今日简报
    INTERACT = "interact"       # 白天交互模式（等待用户操作）
    THREE_DAY = "three_day"     # 每三天自动总结
    CONSOLIDATE = "consolidate" # 晚间整理
    DONE = "done"               # 标记今日完成


# ============================================================
# 状态转移表
# ============================================================
_TRANSITIONS = {
    (LoopState.LAUNCH, "need_summary"):    LoopState.FAMILY_QUIZ,
    (LoopState.LAUNCH, "already_done"):    LoopState.INTERACT,
    (LoopState.FAMILY_QUIZ, "ok"):         LoopState.SUMMARIZE,
    (LoopState.SUMMARIZE, "ok"):           LoopState.ANALYZE,
    (LoopState.ANALYZE, "ok"):             LoopState.BRIEF,
    (LoopState.BRIEF, "ok"):               LoopState.INTERACT,
    (LoopState.INTERACT, "day_ended"):     LoopState.CONSOLIDATE,
    (LoopState.CONSOLIDATE, "need_3day"):  LoopState.THREE_DAY,
    (LoopState.CONSOLIDATE, "ok"):         LoopState.DONE,
    (LoopState.THREE_DAY, "ok"):           LoopState.DONE,
}


# ============================================================
# 状态位管理
# ============================================================
class DailyStatus:
    """管理每日状态位"""

    STATUS_FILE = STATUS_FILE

    @staticmethod
    def load() -> dict:
        """加载状态位文件"""
        if STATUS_FILE.exists():
            with open(STATUS_FILE, 'r', encoding='utf-8') as f:
                return json.load(f)
        return {}

    @staticmethod
    def save(status: dict):
        """保存状态位文件"""
        PRESETS_DIR.mkdir(parents=True, exist_ok=True)
        with open(STATUS_FILE, 'w', encoding='utf-8') as f:
            json.dump(status, f, ensure_ascii=False, indent=2)

    @staticmethod
    def is_today_done() -> bool:
        """检查今日是否已完成总结"""
        today = datetime.date.today().isoformat()
        status = DailyStatus.load()
        return status.get(today, {}).get("summary_done", False)

    @staticmethod
    def mark_summary_done():
        """标记今日总结完成"""
        today = datetime.date.today().isoformat()
        status = DailyStatus.load()
        status[today] = status.get(today, {})
        status[today]["summary_done"] = True
        status[today]["completed_at"] = datetime.datetime.now().isoformat()
        DailyStatus.save(status)

    @staticmethod
    def mark_day_ended():
        """标记今日结束"""
        today = datetime.date.today().isoformat()
        status = DailyStatus.load()
        status[today] = status.get(today, {})
        status[today]["day_ended"] = True
        status[today]["ended_at"] = datetime.datetime.now().isoformat()
        DailyStatus.save(status)

    @staticmethod
    def get_last_summary_date() -> str | None:
        """获取最近一次总结的日期"""
        status = DailyStatus.load()
        done_dates = [d for d, v in status.items() if v.get("summary_done")]
        return max(done_dates) if done_dates else None

    @staticmethod
    def days_since_last_summary() -> int:
        """距离上次总结的天数"""
        last = DailyStatus.get_last_summary_date()
        if last is None:
            return 999
        last_date = datetime.date.fromisoformat(last)
        return (datetime.date.today() - last_date).days

    @staticmethod
    def should_three_day_summary() -> bool:
        """检查是否需要进行三天总结"""
        return DailyStatus.days_since_last_summary() >= 3


# ============================================================
# 主循环引擎
# ============================================================
class PregoPalLoop:
    """核心循环引擎"""

    def __init__(self):
        self.plugins = PluginRegistry()
        self.state = LoopState.LAUNCH
        self.context = LoopContext()
        self._register_default_plugins()

    def _register_default_plugins(self):
        """注册默认插件"""
        from plugins.family_quiz import FamilyRecipeQuizPlugin, WeightQuizPlugin
        from plugins.diet_summary import DietSummaryPlugin
        from plugins.weight_check import WeightCheckPlugin
        from plugins.family_memory import FamilyMemoryPlugin
        from plugins.dri_analysis import DRIAnalysisPlugin
        from plugins.briefing_generator import BriefingGeneratorPlugin
        from plugins.three_day_summary import ThreeDaySummaryPlugin
        from plugins.preset_writer import PresetWriterPlugin

        self.plugins.register(FamilyRecipeQuizPlugin())
        self.plugins.register(WeightQuizPlugin())
        self.plugins.register(DietSummaryPlugin())
        self.plugins.register(WeightCheckPlugin())
        self.plugins.register(FamilyMemoryPlugin())
        self.plugins.register(DRIAnalysisPlugin())
        self.plugins.register(BriefingGeneratorPlugin())
        self.plugins.register(ThreeDaySummaryPlugin())
        self.plugins.register(PresetWriterPlugin())

    async def run(self) -> None:
        """主循环入口"""
        while self.state is not LoopState.DONE:
            handler_name = f"_state_{self.state.value}"
            handler = getattr(self, handler_name)
            event = await handler()
            next_state = _TRANSITIONS.get((self.state, event))
            if next_state is None:
                raise RuntimeError(
                    f"No transition from {self.state} on '{event}'"
                )
            self.state = next_state

    # ============================================================
    # 状态处理器
    # ============================================================

    async def _state_launch(self) -> str:
        """启动检查：检查今日状态位"""
        if DailyStatus.is_today_done():
            return "already_done"
        return "need_summary"

    async def _state_family_quiz(self) -> str:
        """家庭问卷：检查是否需要询问菜谱/体重"""
        for plugin in self.plugins.get_plugins(LoopStage.FAMILY_QUIZ):
            result = await plugin.run(self.context)
            if not result.success:
                self.context.errors.append(result.message)
        return "ok"

    async def _state_summarize(self) -> str:
        """昨日总结：执行所有 SUMMARIZE 阶段插件"""
        for plugin in self.plugins.get_plugins(LoopStage.SUMMARIZE):
            result = await plugin.run(self.context)
            if not result.success:
                self.context.errors.append(result.message)
        return "ok"

    async def _state_analyze(self) -> str:
        """营养分析：执行所有 ANALYZE 阶段插件"""
        for plugin in self.plugins.get_plugins(LoopStage.ANALYZE):
            result = await plugin.run(self.context)
            if not result.success:
                self.context.errors.append(result.message)
        return "ok"

    async def _state_brief(self) -> str:
        """生成今日简报：执行所有 BRIEF 阶段插件"""
        for plugin in self.plugins.get_plugins(LoopStage.BRIEF):
            result = await plugin.run(self.context)
            if not result.success:
                self.context.errors.append(result.message)
        return "ok"

    async def _state_interact(self) -> str:
        """
        白天交互模式：等待用户操作
        此状态由外部事件触发（Gradio 界面交互）
        """
        return "day_ended"

    async def _state_three_day(self) -> str:
        """每三天总结：执行所有 THREE_DAY 阶段插件"""
        for plugin in self.plugins.get_plugins(LoopStage.THREE_DAY):
            result = await plugin.run(self.context)
            if not result.success:
                self.context.errors.append(result.message)
        return "ok"

    async def _state_consolidate(self) -> str:
        """晚间整理：执行所有 CONSOLIDATE 阶段插件"""
        for plugin in self.plugins.get_plugins(LoopStage.CONSOLIDATE):
            result = await plugin.run(self.context)
            if not result.success:
                self.context.errors.append(result.message)

        if DailyStatus.should_three_day_summary():
            return "need_3day"
        return "ok"

    async def _state_done(self) -> str:
        """标记今日完成"""
        DailyStatus.mark_day_ended()
        return "done_complete"

    # ============================================================
    # 外部接口
    # ============================================================

    def get_briefing(self) -> dict:
        """获取今日简报"""
        return self.context.briefing

    def get_thinking_keywords(self) -> str:
        """获取当前思考关键词（用于 UI 显示）"""
        return self.context.briefing.get("thinking_keywords", "")

    def get_errors(self) -> list[str]:
        """获取错误列表"""
        return self.context.errors

    def run_sync(self):
        """同步运行（用于非异步环境）"""
        asyncio.run(self.run())


# ============================================================
# 便捷函数
# ============================================================
def run_daily_loop():
    """运行每日循环（同步入口）"""
    loop = PregoPalLoop()
    loop.run_sync()
    return loop


def check_and_run_loop() -> PregoPalLoop:
    """
    检查并运行循环（供 Gradio 启动时调用）
    
    如果今日已总结，直接返回 loop 实例（不执行总结流程）
    如果今日未总结，执行完整总结流程
    """
    loop = PregoPalLoop()
    if not DailyStatus.is_today_done():
        loop.run_sync()
    return loop