import redis
from datetime import datetime

class RedisHandler:
    def __init__(self, host='localhost', port=6379, db=0, expire_time=60 * 60 * 24 * 30):   # Keep data for 30 days
        self.client = redis.Redis(host=host, port=port, db=db)
        self.expire_time = expire_time

    def save_measurement(self, cell_id, voltage, current, temperature):
        """Save cell measurements with timestamp"""
        timestamp = datetime.now().isoformat()
        key = f"cell:{cell_id}:measurements:{timestamp}"
        self.client.hmset(key, {
            'voltage': voltage,
            'current': current,
            'temperature': temperature
        })
        self.client.expire(key, self.expire_time)

    def get_capacity_estimate(self, cell_id):
        """Calculate estimated capacity based on historical data"""
        measurements = self.client.keys(f"cell:{cell_id}:measurements:*")
        if not measurements:
            return None
            
        # TODO: Put the capacity estimation algorithm
        # based on voltage curves, current integration, etc.
        return float(self.client.get(f"cell:{cell_id}:estimated_capacity") or 0)