#!/bin/sh
set -e
[ -n "$DEBUG" ] && set -x

args="--title=mpvdiff --hwdec=v4l2m2m-copy"

if [ "$1" = "-h" ]; then
	printf "usage: %s [-2|-4] VIDEO..." "$(basename "$0")"
	exit 2

elif [ "$1" = "-4" ]; then
	shift
	mpv "$1" \
		--external-file="$2" \
		--external-file="$3" \
		--external-file="$4" \
		--lavfi-complex='[vid1][vid2]scale2ref[1][2];[1][2]hstack[t1] ; [vid3][vid4]scale2ref[3][4];[3][4]hstack[t2] ; [t1][t2]scale2ref[5][6];[5][6]vstack[vo]' \
		"$args"
else
	mpv "$1" \
		--external-file="$2" \
		--lavfi-complex='[vid1][vid2]scale2ref[1][2];[1][2]hstack[vo]' \
		"$args"
fi