#!/bin/bash

#Usage
#	xpause [resume]
# Click on a window to pause its process, or resume all such paused processes

#return status:
#	0 - Ok
#	1 - kill failed
#	2 - no pid found to resume
#	3 - failed to get pid from window

if test "$1" = "resume" ; then
	if test -s /tmp/xpause ; then
		kill -SIGCONT $(cat /tmp/xpause) || ( echo "xpause FAILED (kill)" ; exit 1 )
		echo "xunpaused $(cat /tmp/xpause | wc -l)"
		rm /tmp/xpause
		exit 0
	fi
	echo "xpause FAILED" "No process to resume"
	exit 2
fi

pid=$(xprop | grep PID | cut -d "=" -f 2)
test "$pid" -gt 0 || ( echo "xpause failed to get pid from window" ; exit 3 )

if test -s /tmp/xpause ; then
	if grep "$pid" /tmp/xpause ; then
		if kill -SIGCONT "$pid" ; then
			echo "unpaused $pid" 
			exit 0 
		else
			echo "xunpause FAILED (kill -SIGCONT \"$pid\")"
			exit 1
		 fi
	fi
fi

echo $pid >> /tmp/xpause
kill -s "SIGSTOP" $pid || ( echo "xpause FAILED (kill - SIGSTOP $pid)" ; exit 1 )
echo "xpaused $pid"
exit 0