import datetime
import pytz
from sqlalchemy import select
from sqlalchemy.orm import Session
from sqlalchemy.orm.exc import NoResultFound
from backend.app.db.models.solar import Solar, SolarScenario


def get_solar_data(session: Session, longitude: float = None, latitude: float = None, uprn: str = None):
    """
    This function will fetch data from the solar table based on longitude and latitude or UPRN.
    :param session: The database session
    :param longitude: The longitude to search for
    :param latitude: The latitude to search for
    :param uprn: The UPRN to search for (overrides longitude and latitude if provided)
    :return: The google_api_response and updated_at fields
    """
    try:
        if uprn:
            # Search by UPRN
            solar_data = session.query(Solar.google_api_response, Solar.updated_at).filter_by(uprn=uprn).one()
        else:
            # Search by longitude and latitude
            solar_data = session.query(Solar.google_api_response, Solar.updated_at).filter(
                Solar.longitude == longitude,
                Solar.latitude == latitude
            ).one()

        # Check if updated_at is more than 6 months old
        six_months_ago = datetime.datetime.now(pytz.utc) - datetime.timedelta(days=6 * 30)  # Approximate 6 months
        is_outdated = solar_data.updated_at < six_months_ago

        return solar_data.google_api_response, solar_data.updated_at, is_outdated

    except NoResultFound:
        return None, None, False


def store_batch_data(session: Session, api_data: dict, uprns_to_location: list, scenarios_data: list):
    """
    This function will store the API data to the solar table against all of the UPRNs with longitude and latitude.
    If a record already exists in the Solar table by UPRN, it will be updated instead of creating a new one.
    Similarly, if a scenario exists in SolarScenario by number_panels, it will also be updated.

    :param session: The database session
    :param api_data: The API data to store
    :param uprns_to_location: A list of dictionaries containing UPRN, longitude, and latitude
    :param scenarios_data: A list of dictionaries containing scenario data for each UPRN
    """
    try:
        # Insert or update data into the Solar table
        for data in uprns_to_location:
            existing_solar = session.execute(select(Solar).where(Solar.uprn == data['uprn'])).scalar_one_or_none()

            if existing_solar:
                # Update the existing record
                existing_solar.longitude = data['longitude']
                existing_solar.latitude = data['latitude']
                existing_solar.google_api_response = api_data
                existing_solar.updated_at = datetime.datetime.now(pytz.utc)
                solar_id = existing_solar.id
            else:
                # Insert a new record
                solar_record = Solar(
                    uprn=data['uprn'],
                    longitude=data['longitude'],
                    latitude=data['latitude'],
                    google_api_response=api_data,
                    updated_at=datetime.datetime.now(pytz.utc)
                )
                session.add(solar_record)
                session.flush()  # Flush to get the IDs generated
                session.refresh(solar_record)  # Refresh to populate the ID field
                solar_id = solar_record.id

            # Insert or update data in the SolarScenario table
            for scenario in scenarios_data:
                existing_scenario = session.execute(
                    select(SolarScenario).where(
                        SolarScenario.solar_id == solar_id,
                        SolarScenario.number_panels == scenario['number_panels']
                    )
                ).scalar_one_or_none()

                if existing_scenario:
                    # Update the existing scenario record
                    existing_scenario.scenario_type = scenario['scenario_type']
                    existing_scenario.array_kwhp = scenario['array_kwhp']
                    existing_scenario.lifetime_dc_kwh = scenario['lifetime_dc_kwh']
                    existing_scenario.yearly_dc_kwh = scenario['yearly_dc_kwh']
                    existing_scenario.lifetime_ac_kwh = scenario.get('lifetime_ac_kwh')  # Optional field
                    existing_scenario.yearly_ac_kwh = scenario.get('yearly_ac_kwh')  # Optional field
                    existing_scenario.cost = scenario['cost']
                    existing_scenario.expected_payback_years = scenario.get('expected_payback_years')  # Optional field
                    existing_scenario.panelled_roof_area = scenario['panelled_roof_area']
                    existing_scenario.is_default = scenario['is_default']
                else:
                    # Insert a new scenario record
                    scenario_record = SolarScenario(
                        solar_id=solar_id,
                        scenario_type=scenario['scenario_type'],
                        number_panels=scenario['number_panels'],
                        array_kwhp=scenario['array_kwhp'],
                        lifetime_dc_kwh=scenario['lifetime_dc_kwh'],
                        yearly_dc_kwh=scenario['yearly_dc_kwh'],
                        lifetime_ac_kwh=scenario.get('lifetime_ac_kwh'),  # Optional field
                        yearly_ac_kwh=scenario.get('yearly_ac_kwh'),  # Optional field
                        cost=scenario['cost'],
                        expected_payback_years=scenario.get('expected_payback_years'),  # Optional field
                        panelled_roof_area=scenario['panelled_roof_area'],
                        is_default=scenario['is_default']
                    )
                    session.add(scenario_record)

        # Commit the changes after all operations
        session.commit()

    except Exception as e:
        session.rollback()
        raise e