#!/bin/bash
echo 'Running opendkim boot script'

export DOCKERMAIL_OPENDKIM_ENV_OPEN_DKIM=true
export DOCKERMAIL_OPENDKIM_PORT_8891_TCP_ADDR=172.17.0.10

POSTFIX_MAIN_CF=/etc/postfix/main.cf

env_dump=$(printenv)

OPENDKIM_CONFIG_HEADER="# OpenDKIM - dockermail - start"
OPENDKIM_CONFIG_FOOTER="# OpenDKIM - dockermail - end"

function remove_opendkim () {
  if grep -q "$OPENDKIM_CONFIG_HEADER" "$POSTFIX_MAIN_CF"; then
    sed "/$OPENDKIM_CONFIG_HEADER/,/$OPENDKIM_CONFIG_FOOTER/d" "$POSTFIX_MAIN_CF"
  fi
}

function add_opendkim () {
  if ! grep -q "$OPENDKIM_CONFIG_HEADER" "$POSTFIX_MAIN_CF"; then
    echo "$OPENDKIM_CONFIG_HEADER" >> "$POSTFIX_MAIN_CF"

    echo "milter_default_action = accept" >> "$POSTFIX_MAIN_CF"
    echo "milter_protocol = 2" >> "$POSTFIX_MAIN_CF"

    if [[ $env_dump =~ ^.*PORT_8891_TCP_ADDR=([0-9\.]*) ]] ; then
      echo "smtpd_milters = inet:${BASH_REMATCH[1]}:8891" >> "$POSTFIX_MAIN_CF"
      echo "non_smtpd_milters = inet:${BASH_REMATCH[1]}:8891" >> "$POSTFIX_MAIN_CF"
    fi

    echo "$OPENDKIM_CONFIG_FOOTER" >> "$POSTFIX_MAIN_CF"
  else
    echo "Warning: $POSTFIX_MAIN_CF already contains OpenDKIM configuration, skipping"
  fi
}

if [[ $env_dump =~ ^(.+OPEN_DKIM)= ]] ; then
  if [ ! -z "${BASH_REMATCH[1]}" ]; then
    echo "OPEN_DKIM env set, enabling email signing"
    remove_opendkim # Remove first, to refresh IP info
    add_opendkim
  fi
else
  echo "Cant find OPEN_DKIM env, signing will be disabled"
  remove_opendkim
fi

echo 'Finished opendkim boot script'