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

POSTFIX_MAIN_CF=/etc/postfix/main.cf
POSTFIX_MASTER_CF=/etc/postfix/master.cf

env_dump=$(printenv)

AMAVIS_CONFIG_HEADER="# Amavis - dockermail - start"
AMAVIS_CONFIG_FOOTER="# Amavis - dockermail - end"

function remove_amavis () {
  # main.cf
  if grep -q "$AMAVIS_CONFIG_HEADER" "$POSTFIX_MAIN_CF"; then
    sed "/$AMAVIS_CONFIG_HEADER/,/$AMAVIS_CONFIG_FOOTER/d" "$POSTFIX_MAIN_CF" -i
  fi
  # master.cf
  sed '/^pickup/,/^cleanup/{//!d}' "$POSTFIX_MASTER_CF" -i
  sed "/$AMAVIS_CONFIG_HEADER/,/$AMAVIS_CONFIG_FOOTER/d" "$POSTFIX_MASTER_CF" -i
}

function add_amavis () {
  # main.cf
  if ! grep -q "$AMAVIS_CONFIG_HEADER" "$POSTFIX_MAIN_CF"; then
    echo "$AMAVIS_CONFIG_HEADER" >> "$POSTFIX_MAIN_CF"
    echo "content_filter = smtp-amavis:[amavis]:10024" >> "$POSTFIX_MAIN_CF"
    echo "$AMAVIS_CONFIG_FOOTER" >> "$POSTFIX_MAIN_CF"
  else
    echo "Warning: $POSTFIX_MAIN_CF already contains Amavis configuration, skipping"
  fi
  # master.cf
  if ! grep -q "$AMAVIS_CONFIG_HEADER" "$POSTFIX_MASTER_CF"; then
    sed "/^pickup.*/a \  -o content_filter= \n  -o receive_override_options=no_header_body_checks" $POSTFIX_MASTER_CF -i
    echo "$AMAVIS_CONFIG_HEADER" >> $POSTFIX_MASTER_CF
    echo "smtp-amavis     unix    -       -       -       -       2       smtp" >> $POSTFIX_MASTER_CF
    echo "  -o smtp_data_done_timeout=1200" >> $POSTFIX_MASTER_CF
    echo "  -o smtp_send_xforward_command=yes" >> $POSTFIX_MASTER_CF
    echo "  -o disable_dns_lookups=yes" >> $POSTFIX_MASTER_CF
    echo "  -o max_use=20" >> $POSTFIX_MASTER_CF
    echo "0.0.0.0:10025 inet    n       -       -       -       -       smtpd" >> $POSTFIX_MASTER_CF
    echo "  -o content_filter=" >> $POSTFIX_MASTER_CF
    echo "  -o local_recipient_maps=" >> $POSTFIX_MASTER_CF
    echo "  -o relay_recipient_maps=" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_restriction_classes=" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_delay_reject=no" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_client_restrictions=permit_mynetworks,reject" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_helo_restrictions=" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_sender_restrictions=" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_recipient_restrictions=permit_mynetworks,reject" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_data_restrictions=reject_unauth_pipelining" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_end_of_data_restrictions=" >> $POSTFIX_MASTER_CF
    # Allow the private ip range 172.x.x.x that Docker apparently uses
    echo "  -o mynetworks=172.0.0.0/8" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_error_sleep_time=0" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_soft_error_limit=1001" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_hard_error_limit=1000" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_client_connection_count_limit=0" >> $POSTFIX_MASTER_CF
    echo "  -o smtpd_client_connection_rate_limit=0" >> $POSTFIX_MASTER_CF
    echo "  -o receive_override_options=no_header_body_checks,no_unknown_recipient_checks" >> $POSTFIX_MASTER_CF
    echo "$AMAVIS_CONFIG_FOOTER" >> $POSTFIX_MASTER_CF
  else
    echo "Warning: $POSTFIX_MASTER_CF already contains Amavis configuration, skipping"
  fi
}

if [[ $env_dump =~ ^(.+AMAVIS)= ]] ; then
  if [ ! -z "${BASH_REMATCH[1]}" ]; then
    echo "AMAVIS env set, enabling SPAM filter"
    add_amavis
  fi
else
  echo "Cant find AMAVIS env, SPAM filter will be disabled"
  remove_amavis
fi

echo 'Finished amavis boot script'