from __future__ import annotations

import logging
import time
from datetime import datetime, timedelta, timezone

from sqlalchemy import select
from sqlalchemy.orm import Session

from .config import settings
from .database import SessionLocal
from .importer import import_records
from .logging_config import configure_logging
from .models import OfficialRecordImport


logger = logging.getLogger("rf4.import_scheduler")


def import_is_due(session: Session, *, now: datetime | None = None) -> bool:
    current = now or datetime.now(timezone.utc)
    latest = session.scalar(
        select(OfficialRecordImport.started_at)
        .where(OfficialRecordImport.source_url == settings.official_records_url)
        .order_by(OfficialRecordImport.started_at.desc())
        .limit(1)
    )
    if latest is None:
        return True
    if latest.tzinfo is None:
        latest = latest.replace(tzinfo=timezone.utc)
    return latest <= current - timedelta(seconds=settings.import_interval_seconds)


def run_due_import() -> bool:
    with SessionLocal() as session:
        if not import_is_due(session):
            return False
        run = import_records(
            session,
            url=settings.official_records_url,
            region=settings.official_records_region,
            category=settings.official_records_category,
        )
        logger.info(
            "official import completed",
            extra={
                "event": "official_import_completed", "result": run.status.value,
                "rows_seen": run.rows_seen, "rows_created": run.rows_created,
                "rows_updated": run.rows_updated, "not_modified": run.not_modified,
            },
        )
        return True


def main() -> None:
    configure_logging(settings.log_level)
    logger.info("scheduler started", extra={"event": "scheduler_started", "interval_seconds": settings.import_interval_seconds})
    while True:
        try:
            run_due_import()
        except Exception:
            logger.exception("scheduled official import failed", extra={"event": "official_import_failed"})
        time.sleep(settings.import_interval_seconds)


if __name__ == "__main__":
    main()