"""Datetime related utility functions."""

import datetime

from processing_accounting.flows.custom_export import setting


def formatted_str_to_datetime(formatted_datetime):
    """Convert formatted str datetime to datetime object.

    Args:
        formatted_datetime (str): Custom export formatted datetime string,
            expected formatting:
              '%Y-%m-%d %H:%M:%S' e.g '2018-03-22 16:42:52'

    Returns:
        datetime.datetime: Resulting datetime object
    """
    str_date, str_time = formatted_datetime.split(' ')
    datetime_args = map(int, str_date.split(
        '-') + str_time.split(':'))
    datetime_arg_namees = [
        'year', 'month', 'day', 'hour', 'minute', 'second']
    datetime_obj = datetime.datetime(
        **dict(zip(datetime_arg_namees, datetime_args)))
    return datetime_obj


def is_expired_workflow(download_start):
    """Check if custom export workflow is expired.

    Args:
        download_start (datetime.datetime): Starting time of AVRO file
            downloading time.

    Returns:
        bool: True if workflow has expired, False otherwise

    """
    dt = datetime.timedelta(hours=setting.WORKFLOW_EXPIRATION_TIME)
    now = datetime.datetime.utcnow()
    return download_start + dt <= now