"""
Connexion à ClickHouse
"""
import clickhouse_connect
from typing import Optional
from .config import settings


class ClickHouseClient:
    """Gestionnaire de connexion ClickHouse"""
    
    def __init__(self):
        self._client: Optional[clickhouse_connect.driver.client.Client] = None
    
    def connect(self) -> clickhouse_connect.driver.client.Client:
        """Établit la connexion à ClickHouse"""
        if self._client is None or not self._ping():
            self._client = clickhouse_connect.get_client(
                host=settings.CLICKHOUSE_HOST,
                port=settings.CLICKHOUSE_PORT,
                database=settings.CLICKHOUSE_DB,
                user=settings.CLICKHOUSE_USER,
                password=settings.CLICKHOUSE_PASSWORD,
                connect_timeout=10
            )
        return self._client
    
    def _ping(self) -> bool:
        """Vérifie si la connexion est active"""
        try:
            if self._client:
                self._client.ping()
                return True
        except Exception:
            pass
        return False
    
    def query(self, query: str, params: Optional[dict] = None):
        """Exécute une requête SELECT"""
        client = self.connect()
        return client.query(query, params)
    
    def query_df(self, query: str, params: Optional[dict] = None):
        """Exécute une requête et retourne un DataFrame"""
        client = self.connect()
        return client.query_df(query, params)
    
    def close(self):
        """Ferme la connexion"""
        if self._client:
            self._client.close()
            self._client = None


# Instance globale
db = ClickHouseClient()