# coding=utf-8
"""当天排餐缓存：启动拉取，界面不展示，供识别比对。"""
import json
import os
import threading
from datetime import datetime

from dao.settings import (
    DISH_BASE_CODE,
    DISH_BASE_NAME,
    DISH_MGMT_MEAL_ON_START,
    DISH_SQLITE_PATH,
)
from service.mgmt_client import MgmtApiError, extract_dish_names_from_meals, fetch_today_meals

_CACHE_DIR = os.path.join(os.path.dirname(DISH_SQLITE_PATH) or '.', 'mgmt_cache')
_CACHE_FILE = os.path.join(_CACHE_DIR, 'today_meals.json')


class MealScheduleStore:
    """内存 + 本地文件缓存；不对 UI 暴露明细。"""

    def __init__(self):
        self._lock = threading.RLock()
        self._raw = None
        self._names = set()
        self._date = None
        self._loaded_at = None
        self._error = None
        self._load_file()

    def _load_file(self):
        try:
            if not os.path.isfile(_CACHE_FILE):
                return
            with open(_CACHE_FILE, 'r', encoding='utf-8') as f:
                data = json.load(f)
            self._raw = data.get('raw')
            self._date = data.get('date')
            self._names = set(data.get('names') or [])
            self._loaded_at = data.get('loaded_at')
        except Exception as exc:
            print(f'[WARN] meal cache load failed: {exc}')

    def _save_file(self):
        try:
            os.makedirs(_CACHE_DIR, exist_ok=True)
            with open(_CACHE_FILE, 'w', encoding='utf-8') as f:
                json.dump({
                    'date': self._date,
                    'names': sorted(self._names),
                    'loaded_at': self._loaded_at,
                    'raw': self._raw,
                }, f, ensure_ascii=False, indent=2)
        except Exception as exc:
            print(f'[WARN] meal cache save failed: {exc}')

    def refresh(self, base_name=None, base_code=None, base_id=None, force=False):
        if not force and not DISH_MGMT_MEAL_ON_START and self._names:
            return {'ok': True, 'skipped': True, 'names': len(self._names)}
        base_name = (base_name or DISH_BASE_NAME or '').strip() or None
        base_code = (base_code or DISH_BASE_CODE or '').strip() or None
        try:
            data = fetch_today_meals(
                base_name=base_name,
                base_code=base_code,
                base_id=base_id,
            )
        except MgmtApiError as exc:
            self._error = str(exc)
            print(f'[WARN] meal schedule fetch failed: {exc}')
            return {'ok': False, 'error': str(exc)}

        names = extract_dish_names_from_meals(data)
        with self._lock:
            self._raw = data
            self._names = names
            self._date = (data or {}).get('date') or datetime.now().strftime('%Y-%m-%d')
            self._loaded_at = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
            self._error = None
            self._save_file()

        print(
            f"[OK] meal schedule loaded: date={self._date} "
            f"base={base_name or base_code} dishes={len(names)}"
        )
        return {'ok': True, 'date': self._date, 'names': len(names)}

    def today_dish_names(self):
        with self._lock:
            # 跨日自动视为空，避免用昨天菜单比对
            today = datetime.now().strftime('%Y-%m-%d')
            if self._date and self._date != today:
                return set()
            return set(self._names)

    def has_schedule(self):
        return bool(self.today_dish_names())

    def is_in_today_menu(self, dish_name):
        name = (dish_name or '').strip()
        if not name:
            return False
        return name in self.today_dish_names()

    def summary(self):
        with self._lock:
            return {
                'date': self._date,
                'loaded_at': self._loaded_at,
                'dish_count': len(self._names),
                'error': self._error,
            }


# 进程内单例，供识别比对使用（不在界面展示）
_store = None
_store_lock = threading.Lock()


def get_meal_schedule_store():
    global _store
    with _store_lock:
        if _store is None:
            _store = MealScheduleStore()
        return _store