import pandas as pd
from strategies.base_strategy import BaseStrategy
import logging

class SingleSmaStrategy(BaseStrategy):
    """
    A strategy based on the price crossing a single Simple Moving Average (SMA).
    """
    def __init__(self, strategy_name: str, params: dict):
        super().__init__(strategy_name, params)
        self.sma_period = self.params.get('sma_period', 0)

    def calculate_signals(self, df: pd.DataFrame) -> pd.DataFrame:
        if not self.sma_period or len(df) < self.sma_period:
            logging.warning(f"Not enough data for SMA period {self.sma_period}.")
            df['signal'] = 0
            return df
            
        df['sma'] = df['close'].rolling(window=self.sma_period).mean()
        
        df['signal'] = 0
        df.loc[df['close'] > df['sma'], 'signal'] = 1
        df.loc[df['close'] < df['sma'], 'signal'] = -1
        
        return df