#!/bin/bash

# The DNS-server IP to use for checking the domain->IP mapping
# If the local system has it's own DNS server which maps IPs differently
# this should point to an external DNS like 1.1.1.1
#NAMESERVER="1.1.1.1"
NAMESERVER="2606:4700:4700::1111"

IPV6_INTERFACE_ID="c03c:17ff:feeb:21e7"
IPV6_SUBNET_ID="01"

# ----- END CONFIG -------------------------------


COMMANDS="dirname cat dig"
for COMMAND in $COMMANDS; do
  if ! command -v $COMMAND &> /dev/null
  then
    echo "$COMMAND could not be found!"
    exit 1
  fi
done

set -e


SCRIPTPATH="$( cd "$(dirname "$0")" >/dev/null 2>&1 ; pwd -P )"

DOMAIN="$1"
echo "DOMAIN -------------------> ${DOMAIN}"

LAST_IP_FILE="/tmp/lastIp-${DOMAIN}"
LAST_IP=""
if [ -f "${LAST_IP_FILE}" ]; then
    LAST_IP=$(cat ${LAST_IP_FILE})
fi
echo "Last UPDATE-IP -----------> ${LAST_IP}"

#WAN_IP=$(${SCRIPTPATH}/easyBoxCtrl.sh wan ip 2>/dev/null)
#echo "Current WAN-IP -----------> ${WAN_IP}"

IPV6_PREFIX=$(${SCRIPTPATH}/easyBoxCtrl.sh wan ipv6prefix 2>/dev/null)
echo "Current IPv6-Prefix ------> ${IPV6_PREFIX}"

IPV6_IP="$(sed -r 's/(.*)00::.*/\1/' <<< ${IPV6_PREFIX})${IPV6_SUBNET_ID}:${IPV6_INTERFACE_ID}"
echo "Current IPv6-IP ----------> ${IPV6_IP}"

PROBE_DOMAIN="${DOMAIN}"
if [[ "${PROBE_DOMAIN}" == \*.* ]]; then
    PROBE_DOMAIN="probe.${PROBE_DOMAIN:2}"
    echo "Probe domain is ----------> ${PROBE_DOMAIN}"
fi
DNS_IP=$(dig @${NAMESERVER} +short ${PROBE_DOMAIN} AAAA)
echo "Current DNS-IP -----------> ${DNS_IP}"


if [ "${IPV6_IP}" == "${DNS_IP}" ]; then
	echo "IPs match - nothing to do."
	exit 0
else
    if [ "${LAST_IP}" == "${IPV6_IP}" ]; then
        echo "Last update IP matches current IP - waiting for DNS to propagate changes."
    else
        echo "IP mismatch - trying to update AAAA-record(s)..."
        $SCRIPTPATH/unitedDomainsCtrl.sh ${DOMAIN} ${IPV6_IP}
        
        if [ "$?" == "0" ]; then
            echo "Save UPDATE_IP."
            echo "${IPV6_IP}" > ${LAST_IP_FILE}
        fi
    fi
fi