get-installed

#!/usr/bin/env bash
# send lists of installed programs to dir specified by date

set -e
if (("$(id -u)" == 0)); then
  user_home="$(getent passwd "${SUDO_USER}" | cut -d':' -f6)"
  user="${user_home:6}"
else
  user_home="${HOME}"
  user="${USER}"
fi

base_dir="${user_home}/documents/misc/installed"
current_date="$(date "+%Y%m%d")"
new_dir="${base_dir}/${current_date}"

get_installed() {
  if [[ -n "${with_git}" ]]; then
    if [[ ! -d "${base_dir}/.git" ]]; then
      git init "${base_dir}"
    fi
  fi

  if [[ -d "${new_dir}" ]]; then
    new_dir="${base_dir}/${current_date}-$(date '+%H:%M:%S')"
  fi

  mkdir "${new_dir}" &&
    pacman -Q >"${new_dir}/all"
  cut -d' ' -f1 "${new_dir}/all" >"${new_dir}/no_version"
  pacman -Qm | cut -d' ' -f1 >"${new_dir}/aur"
  diff -y "${new_dir}/no_version" "${new_dir}/aur" |
    awk '{print $2}' |
    sed '/</d' >"${new_dir}/no_aur"

  if [[ -n "${with_git}" ]]; then
    (cd "${base_dir}" && git add . && git commit -m "${user} $(date '+%c')")
  fi

  printf -- '%s %s\n' "Installed programs backed up to" "${new_dir}"
}

case "$1" in
-g | --git)
  with_git="ON"
  get_installed
  ;;
-h | --help)
  cat <<-EOF
		Usage:
		  getInstalled [options] [dir]

		OPTIONS
		  -g, --git    Use git for storing history
	EOF
  exit 0
  ;;
*)
  get_installed
  ;;
esac

exit 0