from datetime import datetime, timezone

from sqlalchemy import delete, select
from sqlalchemy.ext.asyncio import AsyncSession

from app.notifications.models import NotificationLog, PushDeviceToken


async def create_notification_log(db: AsyncSession, *, user_id: int, event_type: str, payload: str) -> None:
    db.add(NotificationLog(user_id=user_id, event_type=event_type, payload=payload))


async def list_user_notifications(db: AsyncSession, *, user_id: int, limit: int = 50) -> list[NotificationLog]:
    result = await db.execute(
        select(NotificationLog)
        .where(NotificationLog.user_id == user_id)
        .order_by(NotificationLog.id.desc())
        .limit(limit)
    )
    return list(result.scalars().all())


async def upsert_push_device_token(
    db: AsyncSession,
    *,
    user_id: int,
    platform: str,
    token: str,
    device_id: str | None,
    app_version: str | None,
) -> PushDeviceToken:
    result = await db.execute(
        select(PushDeviceToken).where(
            PushDeviceToken.user_id == user_id,
            PushDeviceToken.platform == platform,
            PushDeviceToken.token == token,
        )
    )
    existing = result.scalar_one_or_none()
    if existing is not None:
        existing.device_id = device_id
        existing.app_version = app_version
        existing.updated_at = datetime.now(timezone.utc)
        await db.flush()
        return existing

    record = PushDeviceToken(
        user_id=user_id,
        platform=platform,
        token=token,
        device_id=device_id,
        app_version=app_version,
    )
    db.add(record)
    await db.flush()
    return record


async def delete_push_device_token(
    db: AsyncSession,
    *,
    user_id: int,
    platform: str,
    token: str,
) -> int:
    result = await db.execute(
        delete(PushDeviceToken).where(
            PushDeviceToken.user_id == user_id,
            PushDeviceToken.platform == platform,
            PushDeviceToken.token == token,
        )
    )
    return int(result.rowcount or 0)


async def list_push_tokens_for_user(db: AsyncSession, *, user_id: int) -> list[PushDeviceToken]:
    result = await db.execute(
        select(PushDeviceToken).where(PushDeviceToken.user_id == user_id).order_by(PushDeviceToken.id.asc())
    )
    return list(result.scalars().all())