'use strict';

const ffmpeg = require('fluent-ffmpeg');
const fs = require('fs-extra');

const logger = require('../logger')(__filename);

function mux(target, sources) {
    return new Promise((resolve, reject) => sources.reduce((acc, source) => acc.input(source), ffmpeg())
        .videoCodec('copy')
        .audioCodec('copy')
        .on('start', () => {
            logger.verbose(`Muxing ${sources.length} streams to '${target}'`);
        })
        .on('end', (stdout) => {
            logger.verbose(`Muxed and saved '${target}'`);

            resolve(stdout);
        })
        .on('error', () => reject)
        .save(target))
        .then(() => Promise.all(sources.map(source => fs.remove(source))).then(() => {
            logger.verbose(`Cleaned up temporary files for '${target}'`);
        }));
}

module.exports = mux;