Launch an application or bring existing window to the front

launch-or-raise.sh

#!/bin/bash
#
# Sources I found useful:
# - Messing around with WM and windows: https://askubuntu.com/a/127329
# - Command-line arguments: https://stackoverflow.com/a/29754866
# 
# I also needed to run a .desktop file. So you just gonna try to
# `locate .desktop | grep -i whatever`, then link whatever you've got
# to either `{/usr{,/local},~/.local}/share/applications/`. Then you
# can run `gtk-launch emacs.desktop`, whatever.. you can omit
# ".desktop" if you'd like.

function usage {
    echo "Usage: $0 [-R] [-W <wmclass>] [-c <command>] [--] [<name>]"
    echo "-R              switch to workspace with found window"
    echo "-W              search window by classname"
    echo "-c              command to run to spawn new instance"
    echo;
    echo "Unless -c is specified, name will be used to run the program no "
    echo "windows are found.  If -W is not specified, then window title will be "
    echo "used for search instead. Use -R to move to the window's workspace, "
    echo "instead of bringing it up. ";
    exit 1
}

# # saner programming env: these switches turn some bugs into errors
# set -o errexit -o pipefail -o noclobber -o nounset

# Actually a small nuisance here, but I'm keeping it as a snippet
set -o pipefail -o noclobber -o nounset

# -allow a command to fail with !’s side effect on errexit
# -use return value from ${PIPESTATUS[0]}, because ! hosed $?
! getopt --test || usage
if [[ ${PIPESTATUS[0]} -ne 4 ]]; then
    echo 'I’m sorry, `getopt --test` failed in this environment.'
    exit 1
fi

# -regarding ! and PIPESTATUS see above
# -temporarily store output to be able to check for errors
# -activate quoting/enhanced mode (e.g. by writing out “--options”)
# -pass arguments only via   -- "$@"   to separate them correctly
! PARSED=$(getopt --options=c:W:R --name "$0" -- "$@")
if [[ ${PIPESTATUS[0]} -ne 0 ]]; then
    # e.g. return value is 1
    #  then getopt has complained about wrong arguments to stdout
    exit 2
fi

# read getopt’s output this way to handle the quoting right:
eval set -- "$PARSED"

name= wmcls= cmd= move= win=
# now enjoy the options in order and nicely split until we see --
while true; do
    case "$1" in
        -c)
            cmd="$2"
            shift 2
            ;;
        -R)
            move=y
            shift
	    ;;
	-W)
	    wmcls="$2"
	    shift 2
	    ;;
        --)
            shift
            break
	    ;;
        *)
            echo "Programming error"
            exit 3
            ;;
    esac
done

# handle non-option arguments
if [[ $# -ne 1 && -z "$wmcls" ]]; then
    echo "$0: Window title is required"
    exit 4
fi

name="$@"
if [ -z "$cmd" ]; then
  cmd="$@"
fi

if [[ -n "$wmcls" ]]; then
    win=$(xdotool search --onlyvisible --limit 1 --class "$wmcls")

    if [[ -z "$win" ]]; then
	win=$(xdotool search --limit 1 --classname "$wmcls")
    fi
elif [[ -n "$name" ]]; then
    win=$(xdotool search --onlyvisible --limit 1 --name "$name")

    if [[ -z "$win" ]]; then
	win=$(xdotool search --limit 1 --name "$name")
    fi
fi

# Window class you can find uing `xprop WM_CLASS`
if [ -z "$win" ]; then
    # we could not find the window
    eval "$cmd" &
elif [[ "$win" == "$(xdotool getactivewindow)" ]]; then
    # toggle active window
    xdotool windowminimize "$win"
elif [ -z "$move" ]; then
    # switch to the window
    wmctrl -i -R "$win"
else
    # bring the window up
    wmctrl -i -R "$win"
fi