#!/bin/bash

# shellcheck source=../scripts/helpers/index.sh
source /usr/local/bin/helpers/index.sh

# Workaround to support ENABLE_QUOTAS toggling during tests:
# shellcheck source=/dev/null
source /etc/dms-settings 2>/dev/null

function _main() {
  local DATABASE_ACCOUNTS='/tmp/docker-mailserver/postfix-accounts.cf'
  local DATABASE_VIRTUAL='/tmp/docker-mailserver/postfix-virtual.cf'

  _list_entries "${DATABASE_ACCOUNTS}"
}

function _list_entries() {
  local DATABASE=${1}
  _db_should_exist_with_content "${DATABASE}"

  local ENTRY_TO_DISPLAY
  while read -r LINE; do
    ENTRY_TO_DISPLAY=$(_format_list_item "${LINE}")

    echo -e "* ${ENTRY_TO_DISPLAY}\n"
  done < <(_get_valid_lines_from_file "${DATABASE}")
}

function _format_list_item() {
  local LINE=${1}

  local MAIL_ACCOUNT
  MAIL_ACCOUNT=$(echo "${LINE}" | cut -d'|' -f1)

  local WITH_QUOTA
  WITH_QUOTA=$(_quota_show_for "${MAIL_ACCOUNT}")

  local WITH_ALIASES
  WITH_ALIASES=$(_alias_list_for_account "${MAIL_ACCOUNT}")

  local ACCOUNT_ENTRY="${MAIL_ACCOUNT}"
  [[ -n ${WITH_QUOTA}   ]] && ACCOUNT_ENTRY+=" ${WITH_QUOTA}"
  [[ -n ${WITH_ALIASES} ]] && ACCOUNT_ENTRY+="\n    [ aliases -> ${WITH_ALIASES} ]"

  echo "${ACCOUNT_ENTRY}"
}

function _quota_show_for() {
  local MAIL_ACCOUNT=${1}

  [[ ${ENABLE_QUOTAS} -ne 1 ]] && return 0

  local QUOTA_INFO
  # Matches a line where the 3rd column is `type='STORAGE'` - returning the next three column values:
  IFS=' ' read -r -a QUOTA_INFO <<< "$(doveadm quota get -u "${MAIL_ACCOUNT}" | tail +2 | awk '{ if ($3 == "STORAGE") { print $4" "$5" "$6 } }')"

  local CURRENT_SIZE SIZE_LIMIT PERCENT_USED
  # Format the extracted quota storage columns:
  CURRENT_SIZE="$(_bytes_to_human_readable_size "${QUOTA_INFO[0]}")"
  SIZE_LIMIT="$(_bytes_to_human_readable_size "${QUOTA_INFO[1]}")"
  PERCENT_USED="${QUOTA_INFO[2]}%"

  echo "( ${CURRENT_SIZE} / ${SIZE_LIMIT} ) [${PERCENT_USED}]"
}

function _bytes_to_human_readable_size() {
  # `-` represents a non-applicable value (eg: Like when `SIZE_LIMIT` is not set):
  if [[ ${1:-} == '-' ]]; then
    echo '~'
  # Otherwise a value in KibiBytes (1024 bytes == 1k) is expected (Dovecots internal representation):
  elif [[ ${1:-} =~ ^[0-9]+$ ]]; then
    # kibibytes to bytes, converted to approproate IEC unit (eg: MiB):
    echo $(( 1024 * ${1} )) | numfmt --to=iec
  else
    _exit_with_error "Supplied non-number argument '${1:-}' to '_bytes_to_human_readable_size()'"
  fi
}

# Returns a comma delimited list of aliases associated to a recipient (ideally the recipient is a mail account):
function _alias_list_for_account() {
  local GREP_OPTIONS
  local MAIL_ACCOUNT=${1}

  # postfix-virtual.cf sample lines:
  #
  # all@example.com foo@example.com
  # all@example.com foo@example.com,another@example.com
  # all@example.com another@example.com,foo@example.com,yetanother@example.com
  # all@example.com another@example.com,foo@example.com

  GREP_OPTIONS=(
    --ignore-case
    --extended-regexp
    -e "\s${MAIL_ACCOUNT}($|,)" # match first and second sample line
    -e  ",${MAIL_ACCOUNT}($|,)" # match third and fourth sample line
    "${DATABASE_VIRTUAL}"
  )

  if grep --quiet --no-messages "${GREP_OPTIONS[@]}"; then
    grep "${GREP_OPTIONS[@]}" | awk '{print $1;}' | sed ':a;N;$!ba;s/\n/, /g'
  fi
}

_main