import sys, os
sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))

import requests
from datetime import datetime, timedelta
from sqlalchemy import select, func
from sqlalchemy.exc import IntegrityError
from sqlalchemy.dialects.mysql import insert as mysql_insert

from lib import db
from lib import db_schema


def test_num_of_rows(api_key, station_name='운정', date_str=None):
    if date_str is None:
        date_str = (datetime.now() - timedelta(days=1)).strftime('%Y%m%d')

    max_rows = 500
    min_rows = 100

    while max_rows >= min_rows:
        try:
            url = "http://apis.data.go.kr/B552584/ArpltnStatsSvc/getMsrstnAcctoRDyrg"
            params = {
                'serviceKey': api_key,
                'returnType': 'json',
                'numOfRows': str(max_rows),
                'pageNo': '1',
                'inqBginDt': date_str,
                'inqEndDt': date_str,
                'msrstnName': station_name,
            }
            resp = requests.get(url, params=params, timeout=10)
            resp.raise_for_status()
            resp.json()
            print(f"[INFO] numOfRows 최대값 탐색 성공: {max_rows}")
            return max_rows

        except (requests.RequestException, ValueError) as e:
            print(f"[WARN] numOfRows={max_rows} 에러 발생: {e}, 100 감소 후 재시도")
            max_rows -= 100

    print("[WARN] 최소 numOfRows 값(100)도 실패했습니다. 기본값 100 사용")
    return 100

def fetch_air_quality_data_range(start_date_str, end_date_str, api_key, num_of_rows=100, station_name='운정', page_no=1):
    url = "http://apis.data.go.kr/B552584/ArpltnStatsSvc/getMsrstnAcctoRDyrg"
    params = {
        'serviceKey': api_key,
        'returnType': 'json',
        'numOfRows': str(num_of_rows),
        'pageNo': str(page_no),
        'inqBginDt': start_date_str,
        'inqEndDt': end_date_str,
        'msrstnName': station_name,
    }

    try:
        resp = requests.get(url, params=params, timeout=10)
        resp.raise_for_status()
        data = resp.json()
        items = data.get('response', {}).get('body', {}).get('items', [])
        return items
    except requests.RequestException as e:
        print(f"[ERROR] 요청 실패: {e}")
        return []
    except ValueError as e:
        print(f"[ERROR] JSON 파싱 실패: {e}")
        return []

def save_data_to_db(items, conn, table, force_update=False, debug=False):
    for item in items:
        try:
            item_date = datetime.strptime(item['msurDt'], '%Y-%m-%d').date()
        except Exception as e:
            print(f"[ERROR] 날짜 파싱 오류: {item.get('msurDt')} → {e}")
            continue

        data = {
            'date': item_date,
            'pm25': float(item.get('pm25Value')) if item.get('pm25Value') else None,
            'pm10': float(item.get('pm10Value')) if item.get('pm10Value') else None,
            'so2': float(item.get('so2Value')) if item.get('so2Value') else None,
            'co': float(item.get('coValue')) if item.get('coValue') else None,
            'no2': float(item.get('no2Value')) if item.get('no2Value') else None,
            'o3': float(item.get('o3Value')) if item.get('o3Value') else None,
        }

        try:
            if force_update:
                stmt = mysql_insert(table).values(**data)
                on_duplicate_stmt = stmt.on_duplicate_key_update(**data)
                conn.execute(on_duplicate_stmt)
                if debug:
                    print(f"[DEBUG] {item_date} 저장/업데이트 완료 (강제업데이트)")
            else:
                sel = select(table.c.date).where(table.c.date == item_date)
                exists = conn.execute(sel).fetchone()
                if exists:
                    if debug:
                        print(f"[DEBUG] {item_date} 이미 존재. 저장 생략")
                    continue
                ins = table.insert().values(**data)
                conn.execute(ins)
                if debug:
                    print(f"[DEBUG] {item_date} 저장 완료")
        except IntegrityError as e:
            print(f"[ERROR] DB 중복 오류: {e}")
        except Exception as e:
            print(f"[ERROR] DB 저장 실패: {e}")

def get_latest_date(conn, table):
    try:
        sel = select(func.max(table.c.date))
        result = conn.execute(sel).scalar()
        if result is None:
            print("[INFO] 테이블에 데이터가 없습니다.")
        return result
    except Exception as e:
        print(f"[ERROR] 가장 최근 날짜 조회 실패: {e}")
        return None

def main():
    config = db.load_config()
    api_key = config['air_quality_api']['service_key']
    debug = config.get('debug', False)
    force_update = config.get('force_update', False)

    engine = db.engine
    table = db_schema.fg_manager_static_air

    with engine.connect() as conn:
        trans = conn.begin()
        try:
            start_date = datetime.strptime("2017-01-01", "%Y-%m-%d").date()
            end_date = (datetime.now() - timedelta(days=1)).date()

            optimal_num_rows = test_num_of_rows(api_key, date_str=start_date.strftime('%Y%m%d'))
            if debug:
                print(f"[DEBUG] 최적 numOfRows 값: {optimal_num_rows}")

            current_start = start_date
            while current_start <= end_date:
                current_end = current_start + timedelta(days=optimal_num_rows - 1)
                if current_end > end_date:
                    current_end = end_date

                start_str = current_start.strftime('%Y%m%d')
                end_str = current_end.strftime('%Y%m%d')

                if debug:
                    print(f"[DEBUG] {start_str} ~ {end_str} 데이터 요청 중...")

                items = fetch_air_quality_data_range(start_str, end_str, api_key, num_of_rows=optimal_num_rows)

                if items:
                    save_data_to_db(items, conn, table, force_update=force_update, debug=debug)
                else:
                    if debug:
                        print(f"[DEBUG] {start_str} ~ {end_str} 데이터 없음")

                current_start = current_end + timedelta(days=1)

            trans.commit()
        except Exception as e:
            trans.rollback()
            print(f"[ERROR] 트랜잭션 처리 중 오류 발생: {e}")

if __name__ == '__main__':
    main()