import redis
from core import get_logger, settings, DatabaseException

logger = get_logger("database.redis")


class RedisDatabaseHelper:
    _instance = None

    def __new__(cls):
        if not cls._instance:
            cls._instance = super(RedisDatabaseHelper, cls).__new__(cls)
            cls._instance._initialized = False
        return cls._instance

    def __init__(self):
        if self._initialized:
            return
        try:
            pool = redis.ConnectionPool(
                host=settings.redis_host,
                port=settings.redis_port,
                password=settings.redis_password,
                db=settings.redis_db,
                decode_responses=True,
                max_connections=50,
            )
            self.redis = redis.StrictRedis(connection_pool=pool)
            self.redis.ping()
            logger.info("Redis connection established", extra={"extra_data": {"host": settings.redis_host, "db": settings.redis_db}})
        except redis.ConnectionError as e:
            logger.error("Failed to connect to Redis", exc_info=True)
            raise DatabaseException(message="Redis连接失败", detail=str(e))
        self._initialized = True

    def check_connection(self) -> bool:
        """检查 Redis 连接是否正常"""
        try:
            self.redis.ping()
            return True
        except Exception:
            return False