#! /bin/bash

set -e

if [[ ${#} -ne 1 ]]
then
  echo "${0}: usage: generate-dkim-domain domain"
  exit 1
fi

DOMAINNAME=${1}
mkdir -p "/tmp/docker-mailserver/opendkim/keys/${DOMAINNAME}"

if [[ ! -f "/tmp/docker-mailserver/opendkim/keys/${DOMAINNAME}/mail.private" ]]
then
  echo "Creating DKIM private key /tmp/docker-mailserver/opendkim/keys/${DOMAINNAME}/mail.private"
  opendkim-genkey --subdomains --domain="${DOMAINNAME}" --selector=mail -D "/tmp/docker-mailserver/opendkim/keys/${DOMAINNAME}"
fi

# Write to KeyTable if necessary
KEYTABLEENTRY="mail._domainkey.${DOMAINNAME} ${DOMAINNAME}:mail:/etc/opendkim/keys/${DOMAINNAME}/mail.private"
if [[ ! -f "/tmp/docker-mailserver/opendkim/KeyTable" ]]
then
  echo "Creating DKIM KeyTable"
  echo "${KEYTABLEENTRY}" > /tmp/docker-mailserver/opendkim/KeyTable
else
  if ! grep -q "${KEYTABLEENTRY}" "/tmp/docker-mailserver/opendkim/KeyTable"
  then
    echo "${KEYTABLEENTRY}" >> /tmp/docker-mailserver/opendkim/KeyTable
  fi
fi

# Write to SigningTable if necessary
SIGNINGTABLEENTRY="*@${DOMAINNAME} mail._domainkey.${DOMAINNAME}"
if [[ ! -f /tmp/docker-mailserver/opendkim/SigningTable ]]
then
  echo "Creating DKIM SigningTable"
  echo "*@${DOMAINNAME} mail._domainkey.${DOMAINNAME}" > /tmp/docker-mailserver/opendkim/SigningTable
else
  if ! grep -q "${SIGNINGTABLEENTRY}" "/tmp/docker-mailserver/opendkim/SigningTable"
  then
    echo "${SIGNINGTABLEENTRY}" >>/tmp/docker-mailserver/opendkim/SigningTable
  fi
fi