"""Database connection and management."""

from typing import Optional, Any, Dict


class DatabaseConnection:
    """Manages database connections."""
    
    def __init__(self, connection_url: str):
        """Initialize database connection.
        
        Args:
            connection_url: Database connection URL
        """
        self.connection_url = connection_url
        self._connected = False
        self._data: Dict[str, Any] = {}
        
    def connect(self) -> bool:
        """Establish database connection.
        
        Returns:
            True if connection successful
        """
        # Mock connection
        self._connected = True
        return True
        
    def close(self) -> None:
        """Close the database connection."""
        self._connected = False
        
    def execute(self, query: str, params: Optional[tuple] = None) -> Any:
        """Execute a database query.
        
        Args:
            query: SQL query to execute
            params: Optional query parameters
            
        Returns:
            Query results
        """
        if not self._connected:
            raise RuntimeError("Database not connected")
        # Mock execution
        return []
        
    def insert(self, table: str, data: dict) -> int:
        """Insert data into a table.
        
        Args:
            table: Table name
            data: Data to insert
            
        Returns:
            ID of inserted record
        """
        if not self._connected:
            raise RuntimeError("Database not connected")
        # Mock insert
        return 1
        
    def _internal_cleanup(self):
        """Internal cleanup method."""
        self._data.clear()