"""
Utility functions for RAG pipeline.

Provides common utilities like retry logic, validation helpers, etc.
"""

import time
import logging
from typing import Callable, TypeVar, Any

logger = logging.getLogger(__name__)

T = TypeVar("T")


def retry_with_backoff(
    func: Callable[..., T],
    max_retries: int = 3,
    base_delay: float = 1.0,
    max_delay: float = 10.0,
    backoff_multiplier: float = 2.0,
) -> T:
    """
    Retry a function with exponential backoff.

    Args:
        func: Function to retry
        max_retries: Maximum number of retry attempts
        base_delay: Initial delay in seconds
        max_delay: Maximum delay in seconds
        backoff_multiplier: Multiplier for exponential backoff

    Returns:
        Result of the function

    Raises:
        Exception: The last exception if all retries fail
    """
    last_exception = None
    delay = base_delay

    for attempt in range(max_retries):
        try:
            return func()
        except Exception as e:
            last_exception = e
            if attempt < max_retries - 1:
                logger.warning(
                    f"Attempt {attempt + 1}/{max_retries} failed: {e}. "
                    f"Retrying in {delay:.1f}s..."
                )
                time.sleep(delay)
                delay = min(delay * backoff_multiplier, max_delay)
            else:
                logger.error(f"All {max_retries} attempts failed. Last error: {e}")

    raise last_exception