#!/bin/bash

# a wrapper script to run blitzloop on a multi-monitor systems

# where all monitors show the same output (mpv window). it is

# assumed that the browser window (to show and manipulate the

# playlist) is opened on external computer/smartphone

#

# requires X11 as it uses xrandr

#

# things it does:

# - save current monitor layout

# - mirror all monitors (according to the one with greatest resolution)

# - start blitzloop

# - when blitzloop quits: restore the original layout

#

shopt -s lastpipe

echo "Saving current screen layout.."

original_layout=$(

xrandr | awk 'BEGIN {printf "xrandr"

orientation="normal"}

$2 != "connected" { next }

{if ($3 == "primary") {output=$1" --primary"

modepan=$4

if ($5 ~ /^(left|right|inverted)/) { orientation=$5 }

}

else

{output=$1

modepan=$3

if ($4 ~ /^(left|right|inverted)/) { orientation=$4 }

}}

{mode=modepan

sub(/\+.*/, "", mode)

# strip offset from mode

}

{printf " --output %s --mode %s --scale 1 --panning %s --rotate %s",

output, mode, modepan, orientation}

END {print ""}'

)

# monitor with largest number of pixels will be used as a "master"

# others will mirror it

xrandr | sed 's/ primary / /' | grep connected | \

perl -lane 'next unless @F[1] eq "connected";

$res=$area=@F[2];

$area =~ s/([0-9]+)x([0-9]+)\+.*/$1*$2/e;

$res =~ s/\+.*//;

printf "%s %s %s\n", $area, $res, @F[0]' | \

sort -nrk 1 | head -1 | read _ master_resolution master_output

echo "master out: ${master_output} ($master_resolution)"

blitzloop_layout=$(

xrandr | sed 's/ primary / /' | awk -v master_out="${master_output}" -v master_res="${master_resolution}" '

BEGIN {printf "xrandr "}

$2 != "connected" || $1 == master_out { next }

{ output=$1

printf " --output %s --same-as %s --scale-from %s",

output, master_out, master_res

}

END {print ""}

'

)

${blitzloop_layout}

# add options if required (run blitzloop -h to list them)

blitzloop

echo "Restoring original screen layout.."

${original_layout}