#!/bin/sh
set -eu

makefile_pre() {
	cat <<'EOF'
.POSIX:
FFMFLAGS = -y -hide_banner -loglevel warning



.SUFFIXES:
.SUFFIXES: .mpd .webmx

.mpd.webmx:
	cd $(?D) && ffmpeg $(FFMFLAGS) -i $(<F) $(*F).webm
	touch $@


all:
EOF
}

makefile_post() {
	cat <<'EOF'

sources.webmx = $(sources.mpd:.mpd=.webmx)

all: $(sources.webmx) $(combined.webmx)

$(combined.webmx):
	ffmpeg $(FFMFLAGS) `printf ' -i %s' $?` -c copy $*.webm
	mkdir -p processed/"`basename $(*D)`"
	ln $*.webm processed/"`basename $(*D)`"/
	touch $@
EOF
}

mpds() {
	find live/data/*/*/live.mpd | LANG=POSIX.UTF-8 sort
}

mkdeps() {
	mpds | varlist 'sources.mpd'
	mpds | cut -d/ -f1-3 | sed 's,$,/combined.webmx,' | uniq |
		varlist 'combined.webmx'
	printf '\n'

	mpds | sed 's/^\(.*\)\.mpd$/\1.webmx:\t\1.mpd/'
	mpds | sed 's/^\(.*\)\.mpd$/\1.webm:\t\1.webmx/'
	printf '\n'

	mpds | sed 's/\.mpd$/.webm/' | awk -F/ '{
		printf "live/data/%s/combined.webmx:\t%s\n", $3, $0
	}'
}


{
	makefile_pre
	mkdeps
	makefile_post
} | make -f-