#!/bin/sh -e
# -*- mode: sh; indent-tabs-mode: t -*-
#
# 2020 Dennis Camera (dennis.camera at ssrq-sds-fds.ch)
#
# This file is part of cdist.
#
# cdist is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# cdist is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with cdist. If not, see <http://www.gnu.org/licenses/>.
#

die() { echo "$*" >&2; exit 1; }
dief() {
	#shellcheck disable=SC2059
	die "$(printf "$@")"
}
invalid_param() { die "$@"; }
invalid_paramf() { dief "$@"; }


os=$(cat "${__global:?}/explorer/os")

# Check parameters
bootproto=$(cat "${__object:?}/parameter/bootproto")
case $bootproto
in
	(dhcp)
		# Check parameters
		! test -f "${__object:?}/parameter/address" \
			|| invalid_param '--address is invalid for --bootproto dhcp'
		! test -f "${__object:?}/parameter/gateway" \
			|| invalid_param '--gateway is invalid for --bootproto dhcp'
		;;
	(static)
		# TODO
		;;
	(manual)
		# TODO
		;;
	(*)
		invalid_paramf 'Unknown --bootproto: %s\n' "${bootproto}"
		;;
esac

if test -f "${__object:?}/parameter/type"
then
	impl_type=$(cat "${__object:?}/parameter/type")
else
	# Guess the type based on the operating system
	case $os
	in
		(debian)
			os_major=$(grep -o '^[0-9][0-9]*' "${__global:?}/explorer/os_version")
			test "${os_major}" -ge 7 \
				|| die 'Debian versions older than 7 (wheezy) are not supported'

			impl_type=ifupdown.d
			;;
		(devuan)
			impl_type=ifupdown.d
			;;
		(centos|redhat|scientific|suse)
			impl_type=ifcfg
			;;
		(openwrt)
			impl_type=uci
			;;
		(*)
			if test -s "${__object:?}/explorer/has_networkctl"
			then
				impl_type=systemd
			else
				dief "Don't know how to manage interfaces on: %s\n" "${os}"
			fi
			;;
	esac
fi

# Hand over to backend-specific implementation
manifest_file="${__type:?}/files/backends/${impl_type}/manifest"
test -x "${manifest_file}" || dief 'Unknown type: %s\n' "${impl_type}"

# Run backend-specific script
exec "${manifest_file}"