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

if [ "$1" = "-h" ]; then
	printf "usage: %s [FILE]\n" "$(basename "$0")"
	printf "\n"
	printf "Launches wf-recorder(1) with optimized settings.\n"
	printf "If FILE is omitted, \$HOME/Videos/rec_TIMESTAMP.mkv is used.\n"
	printf "Optionally environment vars can be used to tune things:\n"
	printf "  WF_AOUT - defaults to default pulseaudio sink\n"
	printf "  WF_AIN - defaults to default pulseaudio source\n"
	printf "  WF_AMUX - override creation of an pulseaudio sink for muxing\n"
	printf "  WF_VOUT - limit to output, defaults to focused output (swq current output)\n"
	printf "  WF_KEYS - launches wshowkeys(1)\n"
	exit 2
fi

output_file=${1:-"${HOME}/Videos/rec_$(now).mkv"}
audio_output=${WF_AOUT}
audio_input=${WF_AIN}
video_output=${WF_VOUT}
showkeys=${WF_KEYS}
mux_sink=${WF_AMUX}

[ -z "${audio_output}" ] && audio_output=$(pacmd dump | grep "set-default-sink" | cut -d' ' -f2)
[ -z "${audio_input}" ] && audio_input=$(pacmd dump | grep "set-default-source" | cut -d' ' -f2)
[ -z "${video_output}" ] && video_output=$(swq current output)

if [ "${WF_AIN}" = "none" ] && [ -z "${WF_AMUX}" ]; then
	echo "mux: ${audio_output}"
	mux_sink="${audio_output}"
fi

if [ -z "${mux_sink}" ]; then
	mux_sink=wf-mux
	mux_sink_id=
	output_loopback_id=
	input_loopback_id=
	prepare_mux_sink() {
		mux_sink_id=$(pactl load-module module-null-sink sink_name="${mux_sink}" channels=2)
		output_loopback_id=$(pactl load-module module-loopback sink="${mux_sink}" source="${audio_output}.monitor" remix=true)
		input_loopback_id=$(pactl load-module module-loopback sink="${mux_sink}" source="${audio_input}" remix=true)
	}
	teardown_mux_sink() {
		pactl unload-module "${mux_sink_id}"
		pactl unload-module "${output_loopback_id}"
		pactl unload-module "${input_loopback_id}"
	}
	trap '{ teardown_mux_sink >/dev/null; }' EXIT
	prepare_mux_sink >/dev/null
	echo "mux: ${mux_sink}"
fi

if [ -n "${showkeys}" ]; then
	echo "Starting wshowkeys on ${video_output}"
	echo "WARNING: currently the -o flag to force display to a specific output is not implemented" >&2
	#  -o ${video_output}
	sway exec "wshowkeys -a bottom -a left -F 'Iosevka Sparkle 25' -t 1" >/dev/null
	trap '{ pkill wshowkeys; }' EXIT
fi

set -x
wf-recorder -c h264_vaapi -d /dev/dri/renderD128 -o "${video_output}" -a "${mux_sink}.monitor" -f "${output_file}"