Simple(?) scratchpad toggle or create script

[RayZ0rr]

What

The example scratchpad script from hlwm has a warning on resources used. So, here is a (hopefully) simple script that will toggle a scratchpad if present or create a new one if you accidentally kill it. The script accepts two arguments.

1. The first one is for scratchpad name which can be any one of instance, class, title. For examples below, I will use instance.
2. The second argument is to spawn a scratchpad if it doesn't exist. I will use st -n <scratchpad_name> in examples (-n flag in st is the option for specifying instance name. If using class or title or another terminal then change accordingly).

Dependency

1. xdotool
   ( maybe this can be eliminated by using herbstclient itself to list currently visible windows )

USAGE

1. Put the script somewhere and make it executable. I will put in
   Put the following into your herbstluftwm config (~/.config/herbstluftwm/autostart)

hc keybind $Mod-Control-1		spawn ~/.config/herbstluftwm/scripts/scratchpad.sh "hlwmScratch1" "st -n hlwmScratch1"
hc keybind $Mod-Control-2		spawn ~/.config/herbstluftwm/scripts/scratchpad.sh "hlwmScratch2" "st -n hlwmScratch2"
hc keybind $Mod-Control-3		spawn ~/.config/herbstluftwm/scripts/scratchpad.sh "hlwmScratch3" "st -n hlwmScratch3"

# put this somewhere after 'hc unrule -F' line
hc rule instance~hlwmScratch.* floating=on floatplacement=center # float all instances which contains 'hlwmScratch'

NOTE

1. If you are using another terminal instead of st, then use the appropriate flags to set the instance name (first entry in WM_CLASS(STRING) from xprop). For eg in alacritty,
   alacritty --class hlwmScratch4
2. If you want to change instance to title or class then make necessary changes to the example given above for hlwm config file, scratchpad create command, and the scratchpad.sh script.

scratchpad.sh

#!/usr/bin/env bash

# File:           scratchpad.sh
# Description:    Script to toggle or create scratchpad windows
# Author:	  RayZ0rr (https://github.com/RayZ0rr)

name="$1"
command="${@: 2}"

clientsArray=( $(herbstclient foreach C clients. echo C | awk 'BEGIN{ORS=" "} {print $1}') )
for client in "${clientsArray[@]}" ; do

  id=$(echo $client | cut -d '.' -f 2)
  instanceName="$(herbstclient get_attr ${client}.instance)"
  # className=$(herbstclient get_attr "${client}.class")
  # titleName="$(herbstclient get_attr ${client}.title)"

  if [[ "${instanceName}" == "${name}" ]] ; then # If the scratchpad window exists

    visible_wid="$(xdotool search --onlyvisible --classname "${name}" | tail -1 2> /dev/null)"

    if [[ -z "$visible_wid" ]]; then # If the scratchpad window is not visible

      echo "${name} found. Showing scratchpad."
      herbstclient bring ${id} # Bring scratchpad to focus
      exit $?

    else # If the scratchpad window is visible

      echo "Hiding instance of ${name}."
      herbstclient set_attr "${client}.minimized" true # Hide scratchpad
      exit 0

    fi

  fi

done

if [[ $# -ne 2 ]]; then	# If a command to launch it was not provided
  echo "${name} not found. A command was not provided to launch it."
  exit 1
fi

echo "${name} not found. Executing: '${command}'."
$command

# if ! eval "${@: 2}" ; then
if ! [ $? -eq 0 ]; then
  echo "Provided command '${command}' failed"
  exit 1
fi

# Wait for application to be available
while [[ -z "$wid" ]]; do
  sleep 0.05;
  wid="$(xdotool search --classname "${name}" | tail -1 2> /dev/null)"
done

exit 0