chpwd ls improvement

zsh-chpwd-plugin.zsh

# Put this into your ~/.zshrc
# Enables chpwd, which runs a command if you cd/pushd/popd...
# wrapper around ls, which ommits output if more than 1/3 of screen would be used
# Demo https://asciinema.org/a/123167

ls_reduced() {
   files="$(ls -tr --color=always -- "$(pwd)")"
   lines="$(printf -- "%b" "${files}" | wc -l)"
   term_height="$(tput lines)"
   term_target_height="$((term_height/3))"
   lines_ommited="$((lines-term_target_height))"

   if [ "${lines}" -gt "${term_target_height}" ]; then
      printf -- "%b" "${files}\n─ Ommited ${lines_ommited} additional lines ─\n" | tail -${term_target_height}
   else
      printf -- "%b" "${files}\n"
   fi
}

chpwd() { ls_reduced; }