#!/bin/sh

# This file is maintained at http://git.mdcc.cx/ad1810-tachod .

# Copyright: © 2007 Joost van Baal
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License, as published by the Free Software
# Foundation, either version 3 of the License, or (at your option) any later
# version.  There is NO warranty.  A copy of the GNU GPL is available from
# http://www.gnu.org/licenses/.

# ad1810-tachod - annoy the user and chase it away from the computer when it
#   shouldn't be working

# Written 2007-11

#
# Do not annoy more often than every $sleep period.  Choose
# e.g. sleep=10m or sleep=30s.  See sleep(1).
#
sleep=10m

#
# Time to do stuff to leave the system
#
grace=1s

#
# Text to display when annoying the user
#
message="Stop!"

#
# We'll annoy before hour $morning and after hour $evening.
# E.g. when setting
#  morning=8
#  evening=21
# this program will annoy you when you're using your mouse or keyboard
# between 0:00 and 8:00, and it will annoy you when you're active between
# 21:00 and 23:59.
#
morning=9
evening=21

# overrule above default settings
rcfile=$HOME/.ad1810-tachod.rc
test -f $rcfile && . $rcfile

interrupts_keyboard=0
interrupts_mouse=0

annoy() {
    #   possible other implementations:
    #
    # echo "$message"
    #
    # killall ogg123
    #
    #   from http://mdcc.cx/draai:
    # draai quit
    # draai some/annoying/artist
    #
    # xscreensaver-command -lock
    #
    #  from the x11-apps Debian package:
    # xeyes

    # in Debian package x11-utils. FIXME: document fvwm tweaks to grab mouse and focus
    xmessage -nearmouse -timeout 3600 "$message"
}

active(){
    $active_keyboard || $active_mouse
}

checkactive() {
    interrupts_keyboard_old=$interrupts_keyboard
    interrupts_mouse_old=$interrupts_mouse

    active_keyboard=false
    active_mouse=false

    while read irq interrupts rest
    do
        # /proc/interrupts :
        #  1:    1440117   IO-APIC-edge      i8042 (keyboard)
        # 12:   10506555   IO-APIC-edge      i8042 (mouse)
        #
        # this is probably i386-centric
        case "$irq" in
          "1:")
            interrupts_keyboard=$interrupts
            ;;
          "12:")
            interrupts_mouse=$interrupts
            ;;
        esac
    done </proc/interrupts

    test $interrupts_keyboard -ne $interrupts_keyboard_old && active_keyboard=true
    test $interrupts_mouse -ne $interrupts_mouse_old && active_mouse=true
}

while sleep $sleep
do
    hour=`date +%H`
    # if now in 21:00 < 9:00
    if test $hour -le $morning -o $hour -ge $evening
    then
       checkactive
       # if active($time)
       if active
       then
           annoy $message
           sleep $grace
           # reset interrupts: start monitoring again
           checkactive
       fi
    fi
done