"""This module provides useful decorators for common use."""
import logging
import time

logger = logging.getLogger(__name__)


def retry(max_attempts=4, initial_delay=1, delay_multiplier=2,
          retry_on_exception=Exception):
    """Retry call of decorated function in case of Exception.

    If called function raises exception when sleep for
    a delay and then retry. Delay increases by multiplier.

    Args:
        max_attempts (int): maximum number of attempts
        initial_delay (float): delay after first unsuccessful call
        delay_multiplier (float): delay multiplier for each following attempt
        retry_on_exception (Exception class): base exception to being caught
            for retry
    """
    def decorator(func):
        def wrapper(*args, **kwargs):
            delay_between_attempts = initial_delay
            last_exception = None
            for try_attempt in range(1, max_attempts+1):
                try:
                    return func(*args, **kwargs)
                except retry_on_exception as exception:
                    last_exception = exception
                    logger.warning(f'Try {try_attempt} of {max_attempts}. '
                                   f'Got exception: {repr(exception)}')
                    if try_attempt < max_attempts:
                        time.sleep(delay_between_attempts)
                        delay_between_attempts *= delay_multiplier
            else:
                raise last_exception
        return wrapper

    return decorator