import logging
from datetime import date

import httpx
from sqlalchemy.dialects.postgresql import insert as pg_insert
from sqlalchemy.ext.asyncio import AsyncSession

from app.models.holiday import ChineseHoliday

logger = logging.getLogger(__name__)

HOLIDAY_API = "http://timor.tech/api/holiday/year"


def now_in_china() -> date:
    from datetime import datetime
    from zoneinfo import ZoneInfo
    return datetime.now(ZoneInfo("Asia/Shanghai")).date()


async def sync_holidays(db: AsyncSession, year: int) -> int:
    """同步中国节假日数据，返回更新的记录数"""
    url = f"{HOLIDAY_API}/{year}"
    async with httpx.AsyncClient(timeout=15) as client:
        response = await client.get(url)
        data = response.json()

    if data.get("code") != 0:
        logger.error(f"节假日 API 返回错误: {data}")
        return 0

    holidays = data.get("holiday", {})
    if not holidays:
        return 0

    # 也标记周末（周六日但非调休工作日）
    from datetime import timedelta
    current = date(year, 1, 1)
    end = date(year, 12, 31)

    records: dict[date, dict] = {}
    while current <= end:
        dow = current.weekday()  # 0=Mon, 6=Sun
        # 默认：周一~五为工作日，周六日为非工作日
        default_workday = dow < 5
        records[current] = {
            "date": current,
            "is_workday": default_workday,
            "year": year,
            "description": "",
        }
        current += timedelta(days=1)

    # 覆盖节假日数据
    # holiday=true  → 休息日（无论 wage 值）
    # holiday=false → 调休补班日（周末也要上班）
    for date_str, info_str in holidays.items():
        d = date.fromisoformat(f"{year}-{date_str}")
        if d.year != year:
            continue
        info = info_str if isinstance(info_str, dict) else {}
        holiday = info.get("holiday", False)
        name = info.get("name", "")

        records[d]["description"] = name
        records[d]["is_workday"] = not holiday  # holiday=false → 调休工作日

    # Upsert
    values = list(records.values())
    stmt = pg_insert(ChineseHoliday).values(values)
    stmt = stmt.on_conflict_do_update(
        index_elements=["date"],
        set_={"is_workday": stmt.excluded.is_workday,
              "description": stmt.excluded.description},
    )
    result = await db.execute(stmt)
    await db.commit()
    logger.info(f"已同步 {year} 年节假日，{len(values)} 天")
    return result.rowcount


async def is_workday(db: AsyncSession, day: date | None = None) -> bool:
    """判断某天是否为工作日"""
    if day is None:
        day = now_in_china()
    from sqlalchemy import select
    result = await db.execute(
        select(ChineseHoliday.is_workday).where(ChineseHoliday.date == day)
    )
    row = result.fetchone()
    if row is None:
        # 无数据时，按周判断
        return day.weekday() < 5
    return row[0]


async def was_yesterday_workday(db: AsyncSession) -> bool:
    """昨天是工作日吗"""
    from datetime import timedelta
    yesterday = now_in_china() - timedelta(days=1)
    return await is_workday(db, yesterday)