import os
import sys

from dotenv import load_dotenv
from sqlalchemy import create_engine, select
from sqlalchemy.exc import SQLAlchemyError
from sqlalchemy.orm import Session

from db_models import Base, WeatherForecast, save_forecasts
from exporter import export_md
from geo_locator import GeoError, get_geo
from weather_client import WeatherAPIError, get_forecast


def main() -> None:
    load_dotenv()

    try:
        geo = get_geo()
        print(
            f"{geo.city}{'' if geo.lat is None or geo.lon is None else f' ({geo.lat}, {geo.lon})'}"
        )

        forecasts = get_forecast(geo)
        print(f"{len(forecasts)} days forecast")

        database_url = os.getenv("DB_URL", "sqlite:///weather.db").format(
            DB_USER=os.getenv("DB_USER", ""),
            DB_PASSWORD=os.getenv("DB_PASSWORD", ""),
        )
        city = forecasts[0].city
        engine = create_engine(database_url)
        Base.metadata.create_all(engine)
        with Session(engine) as session:
            saved = save_forecasts(session, forecasts)
            records = list(
                session.scalars(
                    select(WeatherForecast)
                    .where(WeatherForecast.city == city)
                    .order_by(WeatherForecast.forecast_date)
                ).all()
            )
        print(f"records: {len(records)}{f' +{saved}' if saved > 0 else ''}")

        output_file = os.getenv("OUTPUT_FILE", "weather_report.md")
        export_md(records, output_file, city)
        print(f"Exported: {output_file}")

        if records:
            dates = sorted(r.forecast_date for r in records)
            print(f"{dates[0]} - {dates[-1]}")
    except (GeoError, WeatherAPIError, SQLAlchemyError) as exc:
        print(f"error: {exc}", file=sys.stderr)
        sys.exit(1)


if __name__ == "__main__":
    main()