checksum_create()
{
  if [[ -f .checksum ]]; then
    echo -e "${color_bred}Checksum already exists.${color_default}"
    return 1
  fi

  find -type f | parallel -- sha1sum {} >> .checksum
  sed -i "/\.checksum/d" .checksum
}

checksum_check()
{
  sha1sum --quiet -c .checksum
}

checksum_update()
{
  if [[ ! -f .checksum ]]; then
    echo -e "${color_bred}Checksum doesn't exists.${color_default}"
    return 1
  fi

  checksum_check && rm .checksum && checksum_create
}