barkdog

barkdog

#!/bin/bash

set -e -u -x

oldlist=""
declare -A idi
current='' # '' codes for "do nothing with that window"

xprop -spy -root _NET_CLIENT_LIST _NET_ACTIVE_WINDOW |\
while read info; do
	if [[ "$info" == _NET_CLIENT_LIST* ]]; then
		if [[ "$info" == "$oldlist" ]]; then
			continue;
		fi
		oldlist="$info"
		unset nidi
		declare -A nidi
		for id in $info; do
			if [[ "$id" != 0x* ]]; then
				continue;
			fi
			id=${id%,}
			id=$((16#${id/0x/}))
			if [[ ${idi["$id"]+_} ]]; then
				nidi["$id"]="${idi["$id"]}"
			else
				# unknown id, get info
				nidi["$id"]=$(xprop -id "$id" WM_CLASS _NET_WM_PID | sed -n '/^WM_CLASS.* = .*\(\"pavucontrol\"\|\"Firefox\"\)/ { n; s/_NET_WM_PID.* = //p; }')
			fi
		done
		unset idi
		declare -A idi
		for k in ${!nidi[@]}; do
			idi["$k"]="${nidi["$k"]}"
		done
		echo ${!idi[@]}
	elif [[ "$info" == _NET_ACTIVE_WINDOW* ]]; then
		id=$((16#${info/*\# 0x/}))
		if [[ -n "$current" ]]; then
			# only stop it if it still has a window to go back to
			haswnd=false
			for wid in $(xdotool search --pid="$current" --maxdepth=2); do
				if [[ ${idi["$wid"]+_} ]]; then
					haswnd=true
					break
				fi
			done
			if $haswnd; then
				kill -s STOP "$current" # TODO: This will fail if I have a process with the wrong user. Should I just accept my fate?
			fi
		fi
		current="${idi[$id]}" 
		if [[ -n "$current" ]]; then
			kill -s CONT "$current"
		fi
	fi
done