import asyncio
import logging

import aiohttp
from volkswagencarnet.vw_connection import Connection
from volkswagencarnet.vw_exceptions import AuthenticationError  # noqa: F401 — re-exported for collect.py

log = logging.getLogger(__name__)


class _Session:
    """Holds the asyncio event loop, aiohttp session, and Connection together."""

    def __init__(
        self,
        loop: asyncio.AbstractEventLoop,
        session: aiohttp.ClientSession,
        connection: Connection,
    ) -> None:
        self._loop = loop
        self._http_session = session
        self.connection = connection

    def run(self, coro):
        return self._loop.run_until_complete(coro)

    @property
    def vehicles(self):
        return self.connection.vehicles


def connect(username: str, password: str) -> _Session:
    loop = asyncio.new_event_loop()
    asyncio.set_event_loop(loop)

    async def _do():
        session = aiohttp.ClientSession(headers={"Connection": "keep-alive"})
        conn = Connection(session, username, password)
        ok = await conn.doLogin()
        if not ok:
            await session.close()
            raise AuthenticationError("Login failed")
        return session, conn

    session, conn = loop.run_until_complete(_do())
    return _Session(loop, session, conn)


def select_vehicle(wc: _Session, vin: str | None):
    """Return (vehicle, error_message). error_message is None on success."""
    vehicles = wc.vehicles
    if not vehicles:
        return None, "No vehicles found in this account"
    if vin:
        vehicle = next((v for v in vehicles if v.vin == vin), None)
        if not vehicle:
            available = [v.vin for v in vehicles]
            return None, f"VIN {vin} not found. Available: {available}"
        return vehicle, None
    return vehicles[0], None


def update(wc: _Session) -> bool:
    """Run one update cycle. Returns True if the library reported success."""
    ok = wc.run(wc.connection.update())
    if not ok:
        log.warning("connection.update() returned False — data may not have refreshed")
    else:
        log.debug("connection.update() succeeded")
    return bool(ok)