#! /usr/bin/env sh

main()
{
	# Handle opts
	opts "$@"
	shift "$OPTS"
	unset OPTS

	# Show help
	[ "$OPT_HELP_ONLY" ] && usage && exit 0

	# Check for dependencies
	if ! which htpasswd > /dev/null 2>&1
	then
		printf "Missing dependency from \$PATH: %s\n" "htpasswd"
		exit 1
	fi

	# Check where input comes from
	if [ -n "$1" ]
	then
		input=$1
	elif [ ! -t 0 ]
	then
		input=$(cat)
	else
		usage
		exit 2
	fi

	# Generate output
	htpasswd -bnBC "${OPT_COST:-10}" "" "$input" | tr -d ':\n'

	printf "\n"
}

opts()
{
	OPTS=0

	while getopts ":c:h" opt
	do
		case "$opt" in
			h) OPT_HELP_ONLY=1 ;;
			c) OPT_COST=$OPTARG ;;
			*)
				printf "Invalid option passed: %s\n" "$OPTARG" >&2
				;;
		esac
	done

	unset opt
}

usage()
{
	cat <<EOF
Usage:
	$(basename "$0") -h
	$(basename "$0") [-c <int>] <plaintext>

Generate a bcrypt hash of the input.

Options:
	-c  Set the cost. Defaults to 10.
	-h  Show this help text and exit.
EOF
}

main "$@"