import argparse

from sqlalchemy import select
from sqlalchemy.orm import Session

from meal_manager.main import engine
from meal_manager.models import Event, Registration, Subscription


def apply_subscriptions():
    parser = argparse.ArgumentParser(description="Apply subscriptions for an event")
    parser.add_argument("event_id", type=int, help="Event ID (required)")
    parser.add_argument(
        "--dry-run", action="store_true", help="Run without making changes"
    )

    args = parser.parse_args()

    # Access the arguments
    event_id = args.event_id
    dry_run = args.dry_run

    with Session(engine) as session:
        subscriptions = session.scalars(select(Subscription)).all()
        event = session.scalars(select(Event).where(Event.id == event_id)).one()

        if dry_run:
            print(f"DRY RUN: Would process event {event_id}")
        else:
            print(f"Processing event {event_id}")

        print(f"There are {len(subscriptions)} subscriptions to process")
        relevant_subscriptions = [
            s for s in subscriptions if s.valid_on(event.event_time.date())
        ]
        print(f"{len(relevant_subscriptions)} of them are relevant to this event")

        for subscription in relevant_subscriptions:
            existing_registration = session.scalars(
                select(Registration).where(
                    Registration.event_id == event.id,
                    Registration.household_id == subscription.household_id,
                )
            ).one_or_none()
            if existing_registration:
                print(
                    f"There is already a registration for {subscription.household.name}. Skipping subscription."
                )
                continue
            reg = Registration(
                event_id=event.id,
                household_id=subscription.household_id,
                num_adult_meals=subscription.num_adult_meals,
                num_children_meals=subscription.num_children_meals,
                num_small_children_meals=subscription.num_small_children_meals,
                comment="Dauerhafte Anmeldung",
            )
            if dry_run:
                print(f"DRY RUN: Would register {subscription.household.name}")
            else:
                session.add(reg)
                print(f"Registered {subscription.household.name}")

        if not dry_run:
            session.commit()