#!/usr/bin/env bash
# Copyright (C) 2018  Luke Shumaker
# Copyright (C) 2023-2023  Umorpha Systems
# SPDX-License-Identifier: AGPL-3.0-or-later
declare -r NAME=osi-extract
declare -r VERSION=20231023

set -euE

install_prefix="$(realpath --logical --canonicalize-missing -- "${BASH_SOURCE[0]}/../..")"
readonly install_prefix

source "${install_prefix}/lib/osi.sh"

main() {
	local arg_mode=copy
	local arg_image=
	local arg_src=
	local arg_dst=

	local args
	if ! args="$(getopt -n "${0##*/}" -o 'hV' -l 'help,version' -- "$@")"; then
		arg_mode=error
	else
		eval "set -- $args"
		while true; do
			case "$1" in
				-V|--version) shift; arg_mode=version;;
				-h|--help) shift; arg_mode=usage;;
				--) shift; break;;
				*) error $EXIT_FAILURE 'Internal error.  The programmer writing this tool screwed up.';;
			esac
		done
		case "$arg_mode" in
			copy)
				if (( $# != 3 )); then
					if (( $# == 0 )); then
						error 0 "Expected 1 positional argument, got none"
					else
						error 0 "Expected 1 positional argument, got %d: %s" "$#" "${*@Q}"
					fi
					arg_mode=error
				else
					arg_image=$1
					arg_src=$2
					arg_dst=$(realpath -ms -- "$3")
				fi
				;;
		esac
	fi
	case "$arg_mode" in
		error)
			print "Try '%q --help' for more information" "${0##*/}" >&2
			return $EXIT_INVALIDARGUMENT
			;;
		version)
			print "%s (osi-tools) %s" "$NAME" "$VERSION"
			return $EXIT_SUCCESS
			;;
		usage)
			print 'Usage: sudo %s [OPTIONS] FILENAME.img IMAGE_SRC_DIR HOST_DST_DIR' "${0##*/}"
			print 'Operating System Image: Extract Files'
			echo
			print 'OPTIONS:'
			print '  -h, --help     display this help'
			print '  -V, --version  output version information'
			return $EXIT_SUCCESS
			;;

		# main code starts here
		copy)
			local mountpoint
			mountpoint=$(mktemp -dt -- "${0##*/}.XXXXXXXXXX")
			trap "rmdir -- ${mountpoint@Q}" EXIT

			_sudo -- "${install_prefix}/bin/osi-mount" --user -- "$arg_image" "$mountpoint" cp -aT -- "$mountpoint/$arg_src" "$arg_dst"
			;;
	esac
}

main "$@"