#!/bin/sh

NIGHT="1900"
DAY="0700"
BRIGHT="1.0"
DIM="0.5"
DISPLAY="lVDS1"

CURTIME="$(date '+%H%M')"

if [ ${CURTIME} -gt ${DAY} ] && [ ${CURTIME} -lt ${NIGHT} ]; then
  [ "$(/usr/bin/xrandr -d :0 --verbose | awk '/Brightness/ {if ($2 < 1.0) print "nok"}')" = "nok" ] && /usr/bin/xrandr --output ${DISPLAY} -d :0 --brightness ${BRIGHT}
elif [ ${CURTIME} -gt ${NIGHT} ] || [ ${CURTIME} -lt ${DAY} ]; then
  [ "$(/usr/bin/xrandr -d :0 --verbose | awk '/Brightness/ {if ($2 > 0.5) print "nok"}')" = "nok" ] && /usr/bin/xrandr --output ${DISPLAY} -d :0 --brightness ${DIM}
fi