#!/bin/bash

usage() {
	cat <<EOF
Usage: imgcrush [options] <files>
EOF
	exit ${1:-0}
}

crush_jpg() {
	local img="$1"
	jpegoptim "${img}"
}

crush_png() {
	local img="$1"
	# apngopt likes to corrupt images.
	pngcrush -e .png.new "${img}"
	mv "${img}.new" "${img}"
}

crush() {
	case $1 in
	*.jpg|*.jpeg) crush_jpg "$1" ;;
	*.png)        crush_png "$1" ;;
	*) echo "${0##*/}: unsupported format: $1" >&2 ;;
	esac
}

main() {
	set -e

	while [[ $# -ne 0 ]] ; do
		case $1 in
		-h) usage ;;
		-x) set -x; shift ;;
		-*) usage 1 ;;
		*)  crush "$1"; shift ;;
		esac
	done
}
main "$@"