#!/bin/sh

# Copyright (C) 2014-2021 Daniel Baumann <daniel.baumann@open-infrastructure.net>
#
# SPDX-License-Identifier: GPL-3.0+
#
# This program 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.
#
# This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.

set -e

. /etc/network-tools/config/ddns-client.conf

# alternatives handling for knsupdate/nsupdate
if command -v knsupdate > /dev/null 2>&1
then
	# knot-dnsutils
	NSUPDATE="knsupdate -k ${TSIG_KEYFILE}"
elif command -v nsupdate > /dev/null 2>&1
then
	# bind9-dnsutils
	NSUPDATE="nsupdate -k ${TSIG_KEYFILE}"
else
	echo "'${HOOK}': need nsupdate from bind9-dnsutils or knot-dnsutils" >&2
	exit 1
fi

# alternatives handling for wget/curl
if command -v wget > /dev/null 2>&1
then
	# wget
	GET="wget -q -O - -U $(basename "${0}")/git"
elif command -v curl > /dev/null 2>&1
then
	# curl
	GET="curl -s -A $(basename "${0}")/git"
else
	echo "'${HOOK}': need wget or curl" >&2
	exit 1
fi

IPV4_ADDRESS="$(${GET} -4 https://tools.bfh.info/api/v0/ipv4/address/ | jq -r -M '.data.ipv4_address')"
IPV6_ADDRESS="$(${GET} -6 https://tools.bfh.info/api/v0/ipv6/address/ | jq -r -M '.data.ipv6_address')"

DATE="$(date +%Y-%m-%d\ %H:%M:%S)"

Update_record ()
{
	ACTION="${1}"
	TYPE="${2}"
	ADDRESS="${3}"

	echo -n "${NAMESERVER}: ${ACTION} ${RECORD}.${ZONE} ${TTL} ${TYPE} ${ADDRESS}:"

# shellcheck disable=SC2086
echo "server ${NAMESERVER}
zone ${ZONE}
ttl ${TTL}
update ${ACTION} ${RECORD}.${ZONE} ${TTL} ${TYPE} ${ADDRESS}
send" | ${NSUPDATE}

	echo " done."
}

# Run
for NAMESERVER in ${NAMESERVERS}
do
	Update_record delete AAAA
	Update_record delete A
	Update_record delete TXT

	echo
done