"""WebSocket factory for exchange-specific connections."""

import logging

from data_collector.binance_ws import BinanceWebSocket

logger = logging.getLogger(__name__)

# Supported exchanges for WebSocket streaming
SUPPORTED_WS = {"binance": BinanceWebSocket}


def create_websocket(exchange_id: str, **kwargs):
    """Create an exchange-specific WebSocket handler.

    Args:
        exchange_id: Exchange identifier (e.g. 'binance')
        **kwargs: Passed to the WebSocket constructor (symbols, timeframe, on_candle)

    Returns:
        WebSocket handler instance

    Raises:
        ValueError: If exchange is not supported for WebSocket streaming
    """
    ws_cls = SUPPORTED_WS.get(exchange_id)
    if ws_cls is None:
        supported = ", ".join(sorted(SUPPORTED_WS.keys()))
        raise ValueError(
            f"WebSocket streaming not supported for '{exchange_id}'. "
            f"Supported: {supported}. "
            f"Use REST polling as fallback for unsupported exchanges."
        )
    return ws_cls(**kwargs)