"""pykrx 기반 OHLCV / 외인-기관 거래대금 수집.

차단 위험을 줄이려고 호출 사이에 짧은 슬립을 둔다. 5년치는 종목당 약 1~2초.
"""
from __future__ import annotations

import logging
import time
from dataclasses import dataclass
from datetime import date, datetime, timedelta

from sqlalchemy import text

from app.db.connection import get_engine

logger = logging.getLogger(__name__)

# pykrx 는 'YYYYMMDD' 형식을 받음
_PYKRX_DATE = "%Y%m%d"


@dataclass
class FetchResult:
    code: str
    source: str
    inserted: int
    updated: int
    error: str | None = None

    def status(self) -> str:
        if self.error:
            return "failed"
        return "ok"


def _to_pykrx(d: date) -> str:
    return d.strftime(_PYKRX_DATE)


def fetch_ohlcv_daily(code: str, start: date, end: date, *, sleep_s: float = 0.2) -> FetchResult:
    """일봉 OHLCV 를 가져와 ohlcv_daily 에 upsert."""
    try:
        from pykrx import stock as krx
        df = krx.get_market_ohlcv(_to_pykrx(start), _to_pykrx(end), code)
    except Exception as exc:  # noqa: BLE001
        logger.exception("pykrx ohlcv failed code=%s", code)
        return FetchResult(code, "pykrx_ohlcv", 0, 0, error=str(exc))
    if df is None or df.empty:
        return FetchResult(code, "pykrx_ohlcv", 0, 0, error="empty")

    engine = get_engine()
    inserted = updated = 0
    with engine.begin() as conn:
        for d, row in df.iterrows():
            try:
                day = d.date() if hasattr(d, "date") else date.fromisoformat(str(d)[:10])
            except Exception:  # noqa: BLE001
                continue
            res = conn.execute(
                text(
                    """
                    INSERT INTO ohlcv_daily (code, date, open, high, low, close, volume)
                    VALUES (:code, :date, :open, :high, :low, :close, :volume)
                    ON CONFLICT (code, date) DO UPDATE
                      SET open=EXCLUDED.open, high=EXCLUDED.high, low=EXCLUDED.low,
                          close=EXCLUDED.close, volume=EXCLUDED.volume
                    RETURNING (xmax = 0) AS inserted
                    """
                ),
                {
                    "code": code,
                    "date": day,
                    "open": float(row.get("시가", 0) or 0),
                    "high": float(row.get("고가", 0) or 0),
                    "low": float(row.get("저가", 0) or 0),
                    "close": float(row.get("종가", 0) or 0),
                    "volume": int(row.get("거래량", 0) or 0),
                },
            )
            r = res.first()
            if r and r[0]:
                inserted += 1
            else:
                updated += 1
    time.sleep(sleep_s)
    return FetchResult(code, "pykrx_ohlcv", inserted, updated)


def fetch_trading_value(code: str, start: date, end: date, *, sleep_s: float = 0.3) -> FetchResult:
    """외인/기관/개인 순매수 거래대금."""
    try:
        from pykrx import stock as krx
        df = krx.get_market_trading_value_by_date(
            _to_pykrx(start), _to_pykrx(end), code,
        )
    except Exception as exc:  # noqa: BLE001
        logger.exception("pykrx trading_value failed code=%s", code)
        return FetchResult(code, "pykrx_trading_value", 0, 0, error=str(exc))
    if df is None or df.empty:
        return FetchResult(code, "pykrx_trading_value", 0, 0, error="empty")

    # 컬럼명: 외국인합계 / 기관합계 / 개인 (pykrx 1.0.x 기준)
    col_foreign = next((c for c in df.columns if "외국인" in c), None)
    col_inst = next((c for c in df.columns if "기관" in c), None)
    col_indiv = next((c for c in df.columns if "개인" in c), None)

    engine = get_engine()
    inserted = updated = 0
    with engine.begin() as conn:
        for d, row in df.iterrows():
            try:
                day = d.date() if hasattr(d, "date") else date.fromisoformat(str(d)[:10])
            except Exception:  # noqa: BLE001
                continue
            res = conn.execute(
                text(
                    """
                    INSERT INTO trading_value_daily (code, date, foreign_net, institution_net, individual_net)
                    VALUES (:code, :date, :f, :i, :p)
                    ON CONFLICT (code, date) DO UPDATE
                      SET foreign_net=EXCLUDED.foreign_net,
                          institution_net=EXCLUDED.institution_net,
                          individual_net=EXCLUDED.individual_net
                    RETURNING (xmax = 0) AS inserted
                    """
                ),
                {
                    "code": code,
                    "date": day,
                    "f": float(row.get(col_foreign, 0) or 0) if col_foreign else 0.0,
                    "i": float(row.get(col_inst, 0) or 0) if col_inst else 0.0,
                    "p": float(row.get(col_indiv, 0) or 0) if col_indiv else 0.0,
                },
            )
            r = res.first()
            if r and r[0]:
                inserted += 1
            else:
                updated += 1
    time.sleep(sleep_s)
    return FetchResult(code, "pykrx_trading_value", inserted, updated)


def backfill_code(code: str, *, years: int = 5) -> list[FetchResult]:
    end = date.today()
    start = end - timedelta(days=365 * years)
    return [
        fetch_ohlcv_daily(code, start, end),
        fetch_trading_value(code, start, end),
    ]