Automatic screen switching for laptops based on xrandr; Checks for connected screens and laptop lid status.

screen_switch_xrandr.zsh

#!/usr/bin/env zsh

local direction="left"

local -a screens; screens=(`xrandr | grep " connected" | awk -F' ' '{print $1}'`)
local lidStatus=`cat /proc/acpi/button/lid/LID/state | awk -F' ' '{print $2}'`

disableAllButLVDS() {
	xrandr --output VGA1 --off
	xrandr --output HDMI1 --off
	xrandr --output HDMI2 --off
	xrandr --output HDMI3 --off
	xrandr --output DP1 --off
	xrandr --output DP2 --off
	xrandr --output DP3 --off
}

disableAll() {
	disableAllButLVDS
	xrandr --output LVDS1 --off
}

if [[ ${#screens} == 1 ]]; then
	print "only internal screen available"
	disableAllButLVDS
	xrandr --output LVDS1 --auto --dpi 96 --primary
	exit
fi

print "lid status: ${lidStatus}"

if [[ ${lidStatus} == 'closed' ]]; then
	local -a screens2; screens2=()
	for i in ${screens}; do
		if [[ ${i} != 'LVDS1' ]]; then
			screens2=($screens2 ${i})
		fi
	done
	screens=($screens2)
fi

print "screens (${#screens}): ${screens}"

local lastScreen=""
local primarySet=false
disableAll
for i in ${screens}; do
	print "enabling: ${i}"

	xrandr --output $i --auto --dpi 96

	if [[ $primarySet == false ]]; then
		print "\tprimary"
		xrandr --output $i --primary
		primarySet=true
	fi

	if [[ -n ${lastScreen} ]]; then
		print "\t${direction} of ${lastScreen}"
		if [[ $direction == "right" ]]; then
			xrandr --output $i --right-of $lastScreen
		else
			xrandr --output $i --left-of $lastScreen
		fi
	fi
	lastScreen=$i
done