import logging

logger = logging.getLogger(__name__)

class SurgeDetector:
    def __init__(self, multiplier: float = 3.0):
        self.multiplier = multiplier

    def detect(self, tickers: list[dict], avg_volumes: dict[str, float]) -> list[str]:
        surged = []
        for t in tickers:
            symbol = t["symbol"]
            if not symbol.endswith("USDT"):
                continue
            current_vol = float(t.get("quoteVolume", 0))
            avg_vol = avg_volumes.get(symbol, 0)
            if avg_vol > 0 and current_vol >= avg_vol * self.multiplier:
                logger.info(f"Surge detected: {symbol} volume {current_vol:.0f} vs avg {avg_vol:.0f}")
                surged.append(symbol)
        return surged