Man hours is simply check-in time minus checkout-time. We normalize this to 8 hours per day (user modifiable) and exclude weekends. Additionally since a person cannot physically work on two files at the same time we divide it out by the number of files in the checkin. It is important to note that man hours is calculated AFTER the event takes pla…

Normalize Man Hours

def normalize_man_hours(**kwargs):
    """
        If the time_difference is less than 8 hours than return that.

        If the time difference is greater than 8 hours we need to limit it to 8 hours per
        day excluding weekends.

    """

    hours, minutes, seconds = kwargs.get('time_difference', "0:0:0").split(":")
    hours, minutes, seconds = int(hours), int(minutes), int(seconds)
    total_seconds = hours * 60 * 60 + minutes * 60 + seconds

    delta = datetime.timedelta(seconds=max([total_seconds, MINIMUM_CHECKOUT_TIME]))

    to_date = kwargs.get('timestamp')
    if isinstance(to_date, basestring):
        to_date = dateutil.parser.parse(re.sub(":000000", "", to_date))

    from_date = to_date - delta
    # log.debug("Start Date:  {}  End Date: {}".format(
    #     from_date.strftime("%c"), to_date.strftime("%c")))

    time_difference = to_date - from_date
    hours, remainder = divmod(time_difference.seconds, 3600)
    minutes, seconds = divmod(remainder, 60)

    # log.debug("Delta days is {} days, {} hours, {} minutes, {} seconds".format(
    #     time_difference.days, hours, minutes, seconds))

    # Filter out weekends
    day_gen = (from_date + datetime.timedelta(days=x + 1) for x in xrange((to_date - from_date).days))
    days = sum(1 for day in day_gen if day.weekday() < 5)

    total_man_hours = time_difference.seconds/3600.0

    if days:
        # I'll give you the hours if it's past the workday ;)
        day_one = abs(datetime.datetime(
            from_date.year, from_date.month, from_date.day,
            settings.ENVISION_LATEST_WORK_HOUR, 0) - from_date)
        day_one_hours = min([day_one.seconds/3600.0, settings.ENVISION_MAX_WORKHOURS_PER_DAY])
        # log.debug("Day one man hours: {}".format(day_one_hours))

        last_day = abs(to_date - datetime.datetime(
            to_date.year, to_date.month, to_date.day,
            settings.ENVISION_EARLIEST_WORK_HOUR, 0))
        last_day_hours = min([last_day.seconds/3600.0, settings.ENVISION_MAX_WORKHOURS_PER_DAY])
        # log.debug("Last day man hours: {}".format(last_day_hours))

        remaining_hours = (days - 1) * settings.ENVISION_MAX_WORKHOURS_PER_DAY

        total_man_hours = day_one_hours + last_day_hours + remaining_hours

    man_hours = total_man_hours / kwargs.get('qty', 1)
    log.debug("Change: {} {} Changes: Man hours: {} Total Man Hours: {}".format(
        kwargs.get('change'),  kwargs.get('qty', 1), man_hours, total_man_hours))
    return {'man_hours': man_hours}