import logging
from typing import List, Dict, Any

from fastapi import WebSocket, WebSocketDisconnect

logger = logging.getLogger(__name__)


class ConnectionManager:
    """Tracks active websocket connections and broadcasts events."""

    def __init__(self) -> None:
        self.active_connections: List[WebSocket] = []

    async def register(self, websocket: WebSocket) -> None:
        await websocket.accept()
        self.active_connections.append(websocket)
        logger.info("WebSocket connected. Total clients: %s", len(self.active_connections))

    def unregister(self, websocket: WebSocket) -> None:
        if websocket in self.active_connections:
            self.active_connections.remove(websocket)
        logger.info("WebSocket disconnected. Total clients: %s", len(self.active_connections))

    async def broadcast_event(self, event_type: str, data: Dict[str, Any]) -> None:
        """Broadcast a generic JSON event to all clients."""
        payload = {
            "type": event_type,
            **data
        }
        stale_connections: list[WebSocket] = []
        for connection in self.active_connections:
            try:
                await connection.send_json(payload)
            except Exception as exc:  # pragma: no cover
                logger.warning("Failed sending payload to websocket: %s", exc)
                stale_connections.append(connection)
        for connection in stale_connections:
            self.unregister(connection)

    async def handle_connection(self, websocket: WebSocket) -> None:
        """Accept and keep the websocket connection alive."""
        await self.register(websocket)
        try:
            while True:
                # We keep the websocket open; we do not expect client messages yet.
                await websocket.receive_text()
        except WebSocketDisconnect:
            self.unregister(websocket)