from typing import Optional


class ValidationError(Exception):
    """Custom exception for JSON schema validation errors."""
    
    def __init__(self, path: str, message: str):
        """Initialize validation error.
        
        Args:
            path: JSON path to the failing field
            message: Human-readable error message
        """
        self.path = path
        self.message = message
        super().__init__(f"Validation error at {path}: {message}")
    
    def __str__(self) -> str:
        """Return formatted error message."""
        return f"Error at {self.path}: {self.message}"
    
    def __repr__(self) -> str:
        """Return detailed representation."""
        return f"ValidationError(path='{self.path}', message='{self.message}')"
    
    def to_dict(self) -> dict:
        """Convert error to dictionary representation.
        
        Returns:
            Dictionary with path and message keys
        """
        return {
            "path": self.path,
            "message": self.message
        }