#!/bin/bash

function _setup_fetchmail
{
  _log 'trace' 'Preparing Fetchmail configuration'

  local CONFIGURATION FETCHMAILRC

  CONFIGURATION='/tmp/docker-mailserver/fetchmail.cf'
  FETCHMAILRC='/etc/fetchmailrc'

  if [[ -f ${CONFIGURATION} ]]
  then
    cat /etc/fetchmailrc_general "${CONFIGURATION}" >"${FETCHMAILRC}"
  else
    cat /etc/fetchmailrc_general >"${FETCHMAILRC}"
  fi

  chmod 700 "${FETCHMAILRC}"
  chown fetchmail:root "${FETCHMAILRC}"
}

function _setup_fetchmail_parallel
{
  _log 'trace' 'Setting up Fetchmail parallel'
  mkdir /etc/fetchmailrc.d/

  # Split the content of /etc/fetchmailrc into
  # smaller fetchmailrc files per server [poll] entries. Each
  # separate fetchmailrc file is stored in /etc/fetchmailrc.d
  #
  # The sole purpose for this is to work around what is known
  # as the Fetchmail IMAP idle issue.
  function _fetchmailrc_split
  {
    local FETCHMAILRC='/etc/fetchmailrc'
    local FETCHMAILRCD='/etc/fetchmailrc.d'
    local DEFAULT_FILE="${FETCHMAILRCD}/defaults"

    if [[ ! -r ${FETCHMAILRC} ]]
    then
      _log 'warn' "File '${FETCHMAILRC}' not found"
      return 1
    fi

    if [[ ! -d ${FETCHMAILRCD} ]]
    then
      if ! mkdir "${FETCHMAILRCD}"
      then
        _log 'warn' "Unable to create folder '${FETCHMAILRCD}'"
        return 1
      fi
    fi

    local COUNTER=0 SERVER=0
    while read -r LINE
    do
      if [[ ${LINE} =~ poll ]]
      then
        # If we read "poll" then we reached a new server definition
        # We need to create a new file with fetchmail defaults from
        # /etc/fetcmailrc
        COUNTER=$(( COUNTER + 1 ))
        SERVER=1
        cat "${DEFAULT_FILE}" >"${FETCHMAILRCD}/fetchmail-${COUNTER}.rc"
        echo "${LINE}" >>"${FETCHMAILRCD}/fetchmail-${COUNTER}.rc"
      elif [[ ${SERVER} -eq 0 ]]
      then
        # We have not yet found "poll". Let's assume we are still reading
        # the default settings from /etc/fetchmailrc file
        echo "${LINE}" >>"${DEFAULT_FILE}"
      else
        # Just the server settings that need to be added to the specific rc.d file
        echo "${LINE}" >>"${FETCHMAILRCD}/fetchmail-${COUNTER}.rc"
      fi
    done < <(_get_valid_lines_from_file "${FETCHMAILRC}")

    rm "${DEFAULT_FILE}"
  }

  _fetchmailrc_split

  local COUNTER=0
  for RC in /etc/fetchmailrc.d/fetchmail-*.rc
  do
    COUNTER=$(( COUNTER + 1 ))
    cat >"/etc/supervisor/conf.d/fetchmail-${COUNTER}.conf" << EOF
[program:fetchmail-${COUNTER}]
startsecs=0
autostart=false
autorestart=true
stdout_logfile=/var/log/supervisor/%(program_name)s.log
stderr_logfile=/var/log/supervisor/%(program_name)s.log
user=fetchmail
command=/usr/bin/fetchmail -f ${RC} -v --nodetach --daemon %(ENV_FETCHMAIL_POLL)s -i /var/lib/fetchmail/.fetchmail-UIDL-cache --pidfile /var/run/fetchmail/%(program_name)s.pid
EOF
    chmod 700 "${RC}"
    chown fetchmail:root "${RC}"
  done

  supervisorctl reread
  supervisorctl update
}