#!/usr/bin/env sh
# args: /path/to/interface-config /path/to/output.conf

inter="$1"
configfile=/etc/inet2.conf

getval() {
  /var/lib/inet2/config.awk "$configfile" "$@"
}

k() {
  while read -r line; do
    echo "$1 = $line"
  done
}

(
  echo "[Interface]"
  getval "interface $inter" ListenPort | k ListenPort
  getval "interface $inter" PrivateKey | k PrivateKey
  getval PrivateKey | k PrivateKey
  echo
  
  getval "interface $inter" peer | while read -r peer; do
    echo "[Peer]"
    getval "interface $inter" "peer $peer" PublicKey | k PublicKey
    getval "interface $inter" "peer $peer" AllowedIPs | k AllowedIPs
    
    domain="$(getval "interface $inter" "peer $peer" Domain)"
    if [ -n "$domain" ]; then
      # it doesn't like domain names in the Endpoint field, so resolve dns here
      v4="$(dig +short "$domain")"
      [ ! "$?" = "0" ] && v4=""
      v6="$(dig +short -t aaaa "$domain")"
      [ ! "$?" = "0" ] && v6=""
      if getval "interface $inter" "peer $peer" IPv4; then
        v6=""
      fi
      addr="[$v6]"
      [ "$addr" = "[]" ] && addr="$v4"
      echo "Endpoint = $addr:$(getval "interface $inter" "peer $peer" Port)"
    else
      getval "interface $inter" "peer $peer" Endpoint | k Endpoint
    fi
    getval "interface $inter" "peer $peer" PersistentKeepalive | k PersistentKeepalive
    echo
  done
) > "$2"