Make alacritty into a pop-up scratchpad

text_scratchpad.sh

#!/usr/bin/env bash

set -Eeuf -o pipefail
shopt -s inherit_errexit

log() {
  echo "$*" > /dev/stderr
}

err() {
  log "$*"
  exit 1
}

main() {
  PATH=/opt/homebrew/bin:/Applications/Alacritty.app/Contents/MacOS:${PATH}

  local platform
  platform=$(uname -s)

  local clip paste ALACRITTY
  case "${platform}" in
    Darwin)
      clip=(pbcopy)
      paste=(pbpaste)
      ;;
    Linux)
      clip=(xclip -r -selection clipboard)
      paste=(xclip -selection clipboard -out)
      ;;
    *)
      err "Unknown platform: ${platform}"
      ;;
  esac

  local tmp_file
  tmp_file=$(mktemp)
  "${paste[@]}" > "${tmp_file}"
  alacritty \
    --class="__text_scratchpad" \
    -e bash -c "nvim -c startinsert \"${tmp_file}\"" &&
    printf "%s" "$(< "${tmp_file}")" | "${clip[@]}"
}
main "$@"