#!/bin/sh

set -e

# TODO: Externalize to site-specific configfile
[ $# -gt 0 ] || set -- morla 5002 -- dvcam ../../content/icon_small.png

exit1() {
	echo >&2 "ERROR: $1"
	exit 1
}

while [ $# -gt 0 ]; do
	case $1 in
	  --)
		shift; break;;
	  *)
		if [ -z "$HOST" ]; then
			HOST=$1
		elif [ -z "$FIRSTPORT" ]; then
			FIRSTPORT=$1
		else
			exit1 "Too many arguments: Max. 2 about target"
		fi
		;;
	esac
	shift
done

# TODO: Externalize to site-specific configfile
[ $# -gt 0 ] || set -- dvcam ../../content/icon_small.png

while [ $# -gt 0 ]; do
	case $1 in
		alsa=*) ALSA=${1#*=}; AINPUT=$((AINPUT+1));;
		alsa) ALSA=default; AINPUT=$((AINPUT+1));;
		dvcam=*) DVCAM=${1#*=}; XINPUT=$((XINPUT+1));;
		dvcam) DVCAM=auto; XINPUT=$((XINPUT+1));;
		dc=*) IIDC=${1#*=}; VINPUT=$((VINPUT+1));;
		dc) IIDC=/dev/fw1; VINPUT=$((VINPUT+1));;
		videofile=*) VFILE=${1#*=}; VINPUT=$((VINPUT+1));;
		*.ffv1|*.yuv|*.vp8|*.vp9) VFILE=$1; VINPUT=$((VINPUT+1));;
		container=*) XFILE=${1#*=}; XINPUT=$((XINPUT+1));;
		*.avi|*.mkv|*.mov|*.mp4|*.ogg|*.ogv|*.webm) XFILE=$1; XINPUT=$((XINPUT+1));;
		*.png) LOGO=$1; WINPUT=$((WINPUT+1));;
		--) shift; break;;
		*) exit1 "Unsupported input: $1";;
	esac
	shift
done

HOST=${HOST:-127.0.0.1}
if [ "$HOST" = "$(hostname --short)" ]; then
	IP=127.0.0.1
else
	IP=$(host "$HOST" | grep -Po 'address \K\S+')
fi

[ -n "$AINPUT$VINPUT$XINPUT" ] || exit1 "Too few arguments: Min. 1 A/V source"
[ -z "$AINPUT" ] || [ -z "$VINPUT" ] || [ -z "$XINPUT" ] || exit1 "Too many arguments: Max. 2 A/V sources"
[ -z "$AINPUT" ] || [ $AINPUT -eq 1 ] || exit1 "Too many arguments: Max. 1 audio source"
[ -z "$VINPUT" ] || [ $VINPUT -eq 1 ] || exit1 "Too many arguments: Max. 1 video source"
[ -z "$WINPUT" ] || [ $WINPUT -eq 1 ] || exit1 "Too many arguments: Max. 1 watermark source"
[ -z "$XINPUT" ] || [ $XINPUT -eq 1 ] || exit1 "Too many arguments: Max. 1 multimedia source"
[ -n "$NOAUDIO" ] || [ -z "$AINPUT$XINPUT" ] || MAYBEAUDIO=1
[ -n "$NOVIDEO" ] || [ -z "$VINPUT$XINPUT" ] || MAYBEVIDEO=1
[ "$AINPUT$VINPUT$XINPUT" = "1" ] || TWOSOURCES=1
VSTREAMINDEX=1
[ -n "$AINPUT" ] || VSTREAMINDEX=0

FIRSTPORT=${FIRSTPORT:-5002} # even number - next 3 ports used too

ACHANNELS=2
AFRAMERATE=48000
ABITRATE=32000

HEIGHT=360
VBITRATE=256000

SAVESTEM="$SAVEDIR/$(date +%Y%m%d-%H%M%S)"
${SAVEDIR:+export FFREPORT=file="$SAVESTEM.log"}

# based on http://www.webmproject.org/docs/encoder-parameters/#real-time-cbr-encoding-and-streaming
# + scale+watermark trick based on http://stackoverflow.com/a/10937357
# + Add 1s latency (deadline)
# + Use same RTP payload types as GStreamer
ffmpeg -hide_banner -threads auto -re \
 ${ALSA:+-f alsa -sample_rate "$AFRAMERATE" -channels "$ACHANNELS" -thread_queue_size 1024 -i "$ALSA"} \
 ${DVCAM:+-f iec61883 -thread_queue_size 64 -i $DVCAM} \
 ${XFILE:+-i "$XFILE"} \
 ${IIDC:+-f libdc1394 -video_size 640x480 -framerate 15 -thread_queue_size 256 -i "$IIDC"} \
 ${VFILE:+-i "$VFILE"} \
 ${LOGO:+-i "$LOGO"} \
 ${MAYBEVIDEO:+-filter_complex \
 "[$VSTREAMINDEX:v]scale=-2:$HEIGHT${WATERMARK:-[v]}${WATERMARK:+[bg]${LOGO:+;
  [bg][$((VSTREAMINDEX+1)):v]overlay=main_w-overlay_w-20:main_h-overlay_h-20[v]}}"} \
 ${SAVEDIR:+-map '0:' ${TWOSOURCES:+-map '1:'} \
 -codec copy \
 -f matroska "file:$SAVESTEM.mkv"} \
 ${MAYBEAUDIO:+-map '0:a' \
 -codec:a libopus -ac "$ACHANNELS" -ar "$AFRAMERATE" -b:a "$ABITRATE" \
 -f rtp -payload_type 111 "rtp://$IP:$FIRSTPORT?pkt_size=1200"} \
 ${MAYBEVIDEO:+-map '[v]' \
 -pix_fmt yuv420p \
 -codec:v vp8 -quality realtime -deadline 1000000 -cpu-used 15 \
 -b:v "$VBITRATE" -minrate "$VBITRATE" -maxrate "$VBITRATE" \
 -undershoot-pct 95 -bufsize $((6000*VBITRATE/1000)) -rc_init_occupancy $((4000*VBITRATE/1000)) \
 -max-intra-rate 0 \
 -qmin 4 -qmax 56 \
 -f rtp -payload_type 100 "rtp://$IP:$((FIRSTPORT+2))?pkt_size=1200"}