#!/usr/bin/bash

set -e
export TMP_DIR="$(mktemp -d)";

cleanup() {
    rm -fr "${TMP_DIR}";
}

trap cleanup EXIT


export INPUT="$1";
export OUTPUT="$(realpath "$2")";
export BASE_URL="$3"

if [ -z "${BASE_URL}" ]; then
    export BASE_URL="CHANGEME";
fi


mkdir -p "${OUTPUT}"

export ORIG="$(pwd)";

cd "${TMP_DIR}"

ffmpeg -i "${INPUT}" -filter_complex "[0:a]channelsplit=channel_layout=stereo[left][right]" -map '[left]' -f s8 -ac 1 -ar 48k "${OUTPUT}/left.s8" -map '[right]' -f s8 -ac 1 -ar 48k "${OUTPUT}/right.s8"
ffmpeg -i "${INPUT}" -vf fps=20 frame%04d.png

ls frame*.png | parallel 'echo {}; python3 ${ORIG}/cc-pic.py -W 164 -H 81 -p cover {} ${OUTPUT}/{.}.cpi'
rm frame*.png

cd "${ORIG}"

export FRAME_COUNT="$(ls ${OUTPUT}/*.cpi | wc -l)";

printf '{"frame_time": 0.05, "frame_count": %d, "video": "%s", "audio": {"l": "%s", "r": "%s"}}\n' "${FRAME_COUNT}" "${BASE_URL}/frame%04d.cpi" "${BASE_URL}/left.s8" "${BASE_URL}/right.s8" > "${OUTPUT}/info.json"