"""History sync background task.

Periodically copies new records from the fail2ban sqlite database into the
BanGUI application archive table to prevent gaps when fail2ban purges old rows.
"""

from __future__ import annotations

import datetime
from typing import TYPE_CHECKING

import structlog

from app.db import open_db
from app.services import history_service
from app.utils.runtime_state import get_effective_settings

if TYPE_CHECKING:
    from fastapi import FastAPI

    from app.config import Settings

log: structlog.stdlib.BoundLogger = structlog.get_logger()

#: Stable APScheduler job id.
JOB_ID: str = "history_sync"

#: Interval in seconds between sync runs.
HISTORY_SYNC_INTERVAL: int = 300

#: Backfill window when archive is empty (seconds).
BACKFILL_WINDOW: int = 648000


async def _run_sync_with_settings(settings: Settings) -> None:
    socket_path: str = settings.fail2ban_socket
    db = await open_db(settings.database_path)

    try:
        synced = await history_service.sync_from_fail2ban_db(db, socket_path)
        log.info("history_sync_complete", synced=synced)
    except Exception:
        log.exception("history_sync_failed")
    finally:
        await db.close()


async def _run_sync(app: FastAPI) -> None:
    await _run_sync_with_settings(get_effective_settings(app))


def register(app: FastAPI) -> None:
    """Register the history sync periodic job.

    Should be called after scheduler startup, from the lifespan handler.
    """
    settings = get_effective_settings(app)
    app.state.scheduler.add_job(
        _run_sync_with_settings,
        trigger="interval",
        seconds=HISTORY_SYNC_INTERVAL,
        kwargs={"settings": settings},
        id=JOB_ID,
        replace_existing=True,
        next_run_time=datetime.datetime.now(tz=datetime.UTC),
    )
    log.info("history_sync_scheduled", interval_seconds=HISTORY_SYNC_INTERVAL)