#!/bin/bash

if [ $# -eq 2 ]; then
  from="$1"
  to="$2"
elif [ $# -ne 0 ]; then
  >&2 echo 'usage: report-installed-packages [from] [to]'
  exit 1
fi

content=$(
  (
    ls '/var/lib/pacman/sync' | \
      grep 'testing\.db$' | \
      sed 's|^|/var/lib/pacman/sync/|' | \
      xargs -rn1 bsdtar -tf | \
      sed -n '
        /\/$/{
          s|/$||
          p
        }
      '
    pacman -Q | \
      tr ' ' '-'
  ) | \
    sort | \
    uniq -d
)

if [ -z "${to}" ] || [ -z "${from}" ]; then
  echo "${content}"
elif [ -n "${content}" ]; then
  printf '%s\n' \
    "From: ${from}" \
    "To: ${to}" \
    "Subject: $(hostname) - report about installed i686 packages" \
    "" \
    "${content}" | \
    sendmailadvanced
fi