"""Connection manager for Socket.io rooms (one room per update job)."""

from app.core.logging import get_logger

logger = get_logger(__name__)


class WSManager:
    """Tracks active Socket.io sessions and job-room subscriptions."""

    def __init__(self) -> None:
        # sid -> set of job rooms the client subscribed to
        self._subscriptions: dict[str, set[str]] = {}

    def register(self, sid: str) -> None:
        self._subscriptions.setdefault(sid, set())
        logger.info("ws.client_connected", sid=sid)

    def unregister(self, sid: str) -> None:
        self._subscriptions.pop(sid, None)
        logger.info("ws.client_disconnected", sid=sid)

    def subscribe(self, sid: str, job_id: int) -> str:
        room = self.room_for(job_id)
        self._subscriptions.setdefault(sid, set()).add(room)
        return room

    def unsubscribe(self, sid: str, job_id: int) -> str:
        room = self.room_for(job_id)
        if sid in self._subscriptions:
            self._subscriptions[sid].discard(room)
        return room

    @staticmethod
    def room_for(job_id: int) -> str:
        return f"job:{job_id}"

    @property
    def client_count(self) -> int:
        return len(self._subscriptions)


ws_manager = WSManager()