import logging
from typing import TYPE_CHECKING

from src import domain

if TYPE_CHECKING:
    from .. import Usecase

log = logging.getLogger(__name__)


async def handle_subscription(
    self: 'Usecase',
    user_telegram_id: int,
    username: str | None,
    invite_link: str,
    first_name: str | None = None,
    last_name: str | None = None,
) -> None:
    placement_post = await self.database.get_placement_post_by_invite_link(invite_link)
    if not placement_post or not placement_post.placement:
        log.warning('PlacementPost not found for invite_link: %s', invite_link)
        return

    placement = placement_post.placement

    subscriber = await self.database.get_telegram_user(telegram_id=user_telegram_id)
    if not subscriber:
        subscriber = domain.TelegramUser(
            telegram_id=user_telegram_id,
            username=username,
            first_name=first_name,
            last_name=last_name,
        )
        await self.database.create_telegram_user(subscriber)
    else:
        subscriber.username = username or subscriber.username
        subscriber.first_name = first_name or subscriber.first_name
        subscriber.last_name = last_name or subscriber.last_name
        await self.database.update_telegram_user(subscriber)

    active_subscription = await self.database.get_active_subscription_by_subscriber_and_project(
        subscriber.id, placement.project_id
    )

    if active_subscription:
        # Пользователь уже подписан на канал через другой placement
        # Это не должно случиться (Telegram не даст подписаться дважды),
        # но если случилось - логируем и игнорируем
        log.warning(
            'User %s (telegram_id: %s) already has active subscription to channel %s via placement %s, '
            'ignoring new subscription attempt via placement %s',
            subscriber.id,
            user_telegram_id,
            placement.project_id,
            active_subscription.placement_id,
            placement.id,
        )
        return

    # Проверяем, была ли раньше подписка через ЭТОТ placement (для реактивации)
    # Note: Subscription now links to placement directly, not placement_post
    existing_sub = await self.database.get_subscription_by_subscriber_and_placement(
        subscriber.id, placement.id
    )

    if existing_sub and existing_sub.status == domain.SubscriptionStatus.UNSUBSCRIBED:
        existing_sub.status = domain.SubscriptionStatus.ACTIVE
        existing_sub.unsubscribed_at = None
        await self.database.update_subscription(existing_sub)

        log.info(
            'Subscription reactivated: subscriber %s (telegram_id: %s) resubscribed via same placement %s',
            subscriber.id,
            user_telegram_id,
            placement.id,
        )
        return

    subscription = domain.Subscription(
        placement_id=placement.id,
        telegram_user_id=subscriber.id,
        invite_link=invite_link,
    )
    await self.database.create_subscription(subscription)

    log.info(
        'Subscription created: subscriber %s (telegram_id: %s) subscribed via placement %s (invite_link: %s)',
        subscriber.id,
        user_telegram_id,
        placement.id,
        invite_link,
    )