timesheet.py

import re
import sys
from decimal import Decimal

def in_seconds(time_str):
    hour, minute = map(int, time_str.split(':'))
    return hour * 60 * 60 + minute * 60

def seconds_to_hours(seconds):
    return seconds / 60 / 60

def minus_reverse(a, b):
    return b - a

def no_zero_decimal(num):
    if num.is_integer():
        return str(int(num))
    return str(num)

with open(sys.argv[1]) as f:
    s = f.read()

line_hours = [
    seconds_to_hours(sum(
        minus_reverse(*(in_seconds(time_str) for time_str in rng.split('-')))
        for rng in re.compile('-'.join(['[0-9]{1,2}:[0-9]{2}'] * 2)).findall(line)))
    for line in re.compile(' *- *').sub('-', s).splitlines()
]

for line, hours in zip(s.splitlines(), line_hours):
    if hours == 0:
        print(line)
    else:
        print(f'{line} ({no_zero_decimal(hours)} hrs)')

dollars = Decimal(sys.argv[2]) * sum(map(Decimal, line_hours))
print()
print(f'Total hours: {sum(line_hours)} hrs = ${dollars}')