#!/bin/bash
# A tool for putting firefox to sleep when it does not have focus.
# Luke Macken <lewk@csh.rit.edu>

alive=1

while true; do
    if xwininfo -id $(xdotool getactivewindow) | egrep -q '(Firefox|Vimperator)'; then
        if [ ! $alive ]; then
            echo "Waking firefox up"
            kill -CONT `pidof firefox`
            alive=1
        fi
    else
        if [ $alive ]; then
            echo "Putting firefox to sleep"
            kill -STOP `pidof firefox`
            alive=
        fi
    fi
    sleep 1
done