#!/usr/bin/env bash

readonly toolName=rspamd

# Already defined by sequencer.sh, but may be overwritten
#readonly seq_configName="${sq_scriptName:?}.cfg"
#readonly seq_configTemplate="${seq_origin:?}/${sq_configName:?}.example"

sq_aptOpt=
sq_config=0

seq_config() {
  ## Called once before executing steps.
  ## e.g. to source a config file manually:
  #. "${seq_origin:?}/${seq_configName:?}"

  ## or to use sequencer api with profile config file support:
  #if initSeqConfig -p "${seq_fileName:?}" "${seq_configTemplate:?}" ; then

  ## or to use sequencer api with global config file:
  #if initSeqConfig "${seq_configName:?}" "${seq_configTemplate:?}" ; then
  #  sq_config=1
  #else
  #  # End if no configuration file exists
  #  dry || return 1
  #fi

  ## Apt cmdline option to suppress user interaction
  interactive || sq_aptOpt="-y"

  ## Disable error checks if external scripts are used
  ## e.g. error on unbound variables
  #disableErrorCheck

  ## Return of non zero value will abort the sequence
  return 0
}

step_1_info() { echo "Setup custom repository for raspberry pi OS"; }
step_1_alias() { echo "install"; }
step_1() {
  local lRaspbianRelease="Raspbian_$(lsb_release -sr)"
  local lFileName="home_susenerf_rspamd-exotic-debian"
  local lRepoUrl="http://download.opensuse.org/repositories/home:/susenerf:/rspamd-exotic-debian"
  exep echo "deb ${lRepoUrl}/${lRaspbianRelease}/ /" "|" sudo tee /etc/apt/sources.list.d/${lFileName}.list
  exep curl -fsSL "${lRepoUrl}/${lRaspbianRelease}/Release.key" "|" gpg --dearmor "|" sudo tee /etc/apt/trusted.gpg.d/${lFileName}.gpg ">" /dev/null
  exe apt update
}

step_2_info() { echo "Install ${toolName} with apt"; }
step_2() {
  exe apt install rspamd redis-server
}

step_10_info() { echo "Add ufw rule for WebUI (11334)"; }
step_10_alias() { echo "ufw"; }
step_10() {
  exe ufw allow 11334/tcp comment "rspamd WebUI"
}

step_50_info() { echo "Notes"; }
step_50_alias() { echo "notes"; }
step_50() {
  color green
  cat <<NOTES_END
# Configuration
  First generate a new encrypted password string to be used
  with the web UI of ${toolName}

  rspamadm pw

  and insert the result into:
  [/etc/rspamd/local.d/worker-controller.inc]
   bind_socket = "*:11334";
   password = <Result of rspamadm pw>
   enable_password = <Result of rspamadm pw>

  [/etc/rspamd/local.d/redis.conf]
   server = "127.0.0.1";
   timeout = 3s;

  [/etc/rspamd/local.d/classifier-bayes.conf]
   backend = "redis";
   autolearn = true;

  [/etc/rspamd/local.d/dkim_signing.conf]
   enabled = false;

  [/etc/rspamd/local.d/milter_headers.conf]
   authenticated_headers = ["authentication-results"];
   use = ["x-spamd-result","x-spam-level","x-spamd-bar", "my-x-spam-score","x-spam-status", "authentication-results"];

   # add X-Spam-Score header (like SA does)
   # Source: https://groups.google.com/forum/#!topic/rspamd/fEdbnG0J18I
   custom {
      my-x-spam-score = <<EOD
        return function(task, common_meta)
          local sc = common_meta['metric_score'] or task:get_metric_score()
          -- return no error
          return nil,
          -- header(s) to add
          {['X-Spam-Score'] = string.format('%.2f', sc[1])},
          -- header(s) to remove
          {['X-Spam-Score'] = 1},
          -- metadata to store
          {}
      end
   EOD;
   }

  [/etc/rspamd/local.d/phishing.conf]
   openphish_enabled = true;
   phishtank_enabled = true;

  [/etc/rspamd/local.d/greylist.conf]
   enabled = true;
   timeout = 1min;

  [/etc/rspamd/local.d/mx_check.conf]
   enabled = true;
   timeout = 5.0;

   # A map of specific domains that should be excluded from MX check
   exclude_domains = [
       "https://maps.rspamd.com/freemail/disposable.txt.zst",
       "https://maps.rspamd.com/freemail/free.txt.zst",
       "\${CONFDIR}/maps.d/maillist.inc",
       "\${CONFDIR}/maps.d/redirectors.inc",
       "\${CONFDIR}/maps.d/dmarc_whitelist.inc",
       "\${CONFDIR}/maps.d/surbl-whitelist.inc",
       "\${CONFDIR}/maps.d/spf_dkim_whitelist.inc",
   ];

## Don't check mails send from local network

  [/etc/rspamd/local.d/multimap.conf]
   IP_WHITELIST {
       type = "ip";
       prefilter = true;
       map = "/\${LOCAL_CONFDIR}/local.d/ip_whitelist.map";
       action = "accept";
       description = "Accept mails from local network"
   }

   #WHITELIST_SENDER_DOMAIN {
   #    type = "from";
   #    filter = "email:domain";
   #    map = "/etc/rspamd/local.d/whitelist.sender.domain.map";
   #    score = -6.0
   #}

  [/etc/rspamd/local.d/ip_whitelist.map]
   fd00::/8
   192.168.0.0/16
   10.0.0.0/8

# Configuring Postfix
  [/etc/postfix/main.cf]
   # Invoke rspamd to check for spam
   smtpd_milters = inet:localhost:11332
   # skip mail without checks if something goes wrong
   milter_default_action = accept

# Global sieve script for spam to junk
  * If sieve before is a folder all scripts inside are executed

  [/etc/dovecot/conf.d/90-sieve.conf]
   sieve_before = /var/lib/dovecot/sieve.d/

  * The global sieve script needs to be compiled with sievec
    and changed group to vmail for access permissions
    (chown root:vmail script; chmod 750 script)

  [/var/lib/dovecot/sieve.d/spam-global.sieve]
   require "fileinto";
   if header :contains "X-Spam-Flag" "YES" {
     fileinto "Junk";
   }

# Configure sieve as replacement for deprecated plugin dovecot-antispam
  https://doc.dovecot.org/configuration_manual/howto/antispam_with_sieve/

  [/etc/dovecot/conf.d/20-imap.conf]
   mail_plugins = \$mail_plugins imap_sieve

  [/etc/dovecot/conf.d/90-sieve.conf]
   sieve_plugins = sieve_imapsieve sieve_extprograms

   # From elsewhere to Spam folder
   imapsieve_mailbox1_name = Spam
   imapsieve_mailbox1_causes = COPY
   imapsieve_mailbox1_before = file:/usr/lib/dovecot/sieve-pipe/report-spam.sieve

   # From Spam folder to elsewhere
   imapsieve_mailbox2_name = *
   imapsieve_mailbox2_from = Spam
   imapsieve_mailbox2_causes = COPY
   imapsieve_mailbox2_before = file:/usr/lib/dovecot/sieve-pipe/report-ham.sieve

   sieve_extensions = +notify +imapflags +vnd.dovecot.execute
   sieve_global_extensions = +vnd.dovecot.pipe +vnd.dovecot.environment

  [/etc/dovecot/conf.d/90-sieve-extprograms.conf
   sieve_pipe_bin_dir = /usr/lib/dovecot/sieve-pipe
   sieve_execute_bin_dir = /usr/lib/dovecot/sieve-execute

  [/usr/lib/dovecot/sieve-pipe/report-spam.sieve]
   require ["vnd.dovecot.pipe", "copy", "imapsieve", "environment", "variables"];
   if environment :matches "imap.user" "*" {
     set "username" "\${1}";
   pipe :copy "rspamd-learn-spam.sh" [ "\${username}" ];

  [/usr/lib/dovecot/sieve-pipe/report-ham.sieve]
   require ["vnd.dovecot.pipe", "copy", "imapsieve", "environment", "variables"];
   if environment :matches "imap.mailbox" "*" {
     set "mailbox" "\${1}";
   }
   if string "\${mailbox}" "Trash" {
     stop;
   }
   if environment :matches "imap.user" "*" {
     set "username" "\${1}";
   }
   pipe :copy "rspamd-learn-ham.sh" [ "\${username}" ];

  [/usr/lib/dovecot/sieve-pipe/rspamd-learn-spam.sh]
   #!/bin/sh
   # rspamc learn is used in parallel. Be aware of system resources when
   # moving multiple messages at the same time
   rspamdNewSpam=\$(cat);( echo "\$rspamdNewSpam" | /usr/bin/rspamc learn_spam ) &

  [/usr/lib/dovecot/sieve-pipe/rspamd-learn-ham.sh]
   #!/bin/sh
   # rspamc learn is used in parallel. Be aware of system resources when
   # moving multiple messages at the same time
   rspamdNewHam=\$(cat);( echo "\$rspamdNewHam" | /usr/bin/rspamc learn_ham ) &
NOTES_END
}

# shellcheck disable=SC2034 # Appears unused
readonly sqr_minVersion=16
# shellcheck disable=SC1091 # Don't follow this source
. /usr/local/bin/sequencer.sh