1	#!/bin/bash
2
3	# get weekly pay (written by Chris and Copilot) - math with bc
4	# use options flags to take in command line arguments for hours and rate
5
6	print_usage() {
7	echo "Usage: $0 [-h] [-r rate] [-t hours]"
8	echo " -h: print usage"
9	echo " -r: hourly rate"
10	echo " -t: hours worked"
11	}
12
13	taxes() {
14	tax_rate=0.15
15	echo "$pay"
16	tax_pay=$(echo "scale=2; $pay * (1-$tax_rate)" | bc)
17	}
18	# define default values for hours and rate (empty string)
19	hours=""
20	rate=""
21
22	# list of arguments allowed in the input
23	# optstring followed by colon means that the option requires an argument
24	optstring="hr:t:"
25
26	# if [ $# -eq 0 ]; then
27	# fi
28
29	# getopts is a bash builtin function that parses command line arguments
30	# valid arguments are in optstring (above) (e.g. -h, -r, -t)
31	# if an invalid argument is passed, while loop will exit and print usage
32	while getopts $optstring opt; do
33	case $opt in
34	h)
35	print_usage
36	exit 0
37	;;
38	r)vs
39	rate=$OPTARG
40	;;
41	t)
42	hours=$OPTARG
43	;;
44	\?)
45	print_usage
46	exit 1
47	;;
48	esac
49	done
50
51	# while loop to check if the arguments are empty
52	while [ -z "$hours" ] || [ -z "$rate" ]; do
53
54	# if the arguments are empty, prompt the user for input
55	if [ -z $hours ]; then
56	echo "hours is required"
57	read -p "enter hours worked: " hours
58	fi
59
60	if [ -z $rate ]; then
61	echo "rate is required"
62	read -p "enter hourly rate: " rate
63	fi
64	done
65
66	echo "hours: $hours"
67	echo "rate: $rate"
68
69	# calculate the weekly pay using bc
70	# using bc because it is a command line calculator and can handle decimals
71	# bash builtin can't handle decimals
72	pay=$(echo "scale=2; $hours * $rate" | bc)
73
74	taxes
75
76	echo "weekly pay is $pay"
77	echo "weekly pay less $( echo "scale=1; $tax_rate * 100"|bc)% taxes is $tax_pay"