# plugins/snmp/scheduler.py
from __future__ import annotations
import asyncio
import logging
from typing import TYPE_CHECKING

if TYPE_CHECKING:
    from quart import Quart

from fabledscryer.core.scheduler import ScheduledTask

logger = logging.getLogger(__name__)


def make_poll_task(app: "Quart") -> ScheduledTask:
    interval = app.config["PLUGINS"]["snmp"].get("poll_interval_seconds", 60)

    async def poll() -> None:
        await _do_poll(app)

    return ScheduledTask(
        name="snmp_poll",
        coro_factory=poll,
        interval_seconds=int(interval),
        run_on_startup=True,
    )


async def _do_poll(app: "Quart") -> None:
    from datetime import datetime, timezone
    from .poller import poll_device_sync
    from fabledscryer.core.alerts import record_metric

    devices: list[dict] = app.config["PLUGINS"]["snmp"].get("devices", [])
    if not devices:
        return

    loop = asyncio.get_event_loop()
    now = datetime.now(timezone.utc)

    async with app.db_sessionmaker() as session:
        async with session.begin():
            for device in devices:
                if not isinstance(device, dict):
                    continue
                name = device.get("name") or device.get("host", "unknown")
                host = device.get("host", "")
                port = int(device.get("port", 161))
                community = device.get("community", "public")
                version = str(device.get("version", "2c"))
                oids = device.get("oids", [])

                if not host or not oids:
                    continue

                try:
                    readings = await loop.run_in_executor(
                        None,
                        poll_device_sync,
                        host, port, community, version, oids,
                    )
                except Exception:
                    logger.exception("SNMP poll failed for device %s (%s)", name, host)
                    continue

                for label, value in readings.items():
                    await record_metric(
                        session=session,
                        source_module="snmp",
                        resource_name=name,
                        metric_name=label,
                        value=value,
                    )

                if readings:
                    logger.debug("SNMP polled %s (%s): %d OID(s)", name, host, len(readings))
                else:
                    logger.debug("SNMP polled %s (%s): no readings", name, host)