// const speech = require('@google-cloud/speech');
const portAudio = require('naudiodon');
// const rs = fs.createReadStream('rawAudio.wav');

const audioContainer = {
    input: '',
    buffers: []
}


let record = true;

// Create an instance of AudioIO with inOptions (defaults are as below), which will return a ReadableStream
const aio = new portAudio.AudioIO({
  inOptions: {
    channelCount: 2,
    sampleFormat: portAudio.SampleFormat16Bit,
    sampleRate: 44100,
    deviceId: -1 // Use -1 or omit the deviceId to select the default device
  },
  outOptions: {
    channelCount: 2,
    sampleFormat: portAudio.SampleFormat16Bit,
    sampleRate: 44100,
    deviceId: -1 // Use -1 or omit the deviceId to select the default device
  }
});


aio.start()
aio.read()
aio.on('data', buf => console.log(buf.timestamp));

const counter = 0;
const tests = [];

function testCallback() {
    play(tests[0])
}

function splitArrayIntoChunksOfLen(buf, len) {
  const chunks = [];
  let i = 0;
  let L = len;
  console.log(buf.byteLength)
  while(i < buf.byteLength) {
      chunks.push(buf.slice(i, L));
      i = L;
      L += len;
  }

  chunks.forEach(c => console.log(c))
  return chunks;
}

function play(input) {
    let i = 0;
    const buf = Buffer.from(input, 'base64');
    // format buffers into half their size to account for writable highwaterMark.
    const audio = splitArrayIntoChunksOfLen(buf, 8192);
    // call this fuction after last audio chunk has been written.
    const callback = () => {
        // TODO: clear portAudio writable buffer on write end.
    }
    write();
    // iterate through audio array and write buffers to portAudio writable.
    function write() {
        let ok = true;
        do {
            if (i === audio.length - 1) {
                // write last chunk.
                ao.write(audio[i], null, callback);
            } else {
                // check for backpreassure.
                ok = ao.write(audio[i], null);
            }
            i++;
        } while (i < audio.length && ok);

        if (i < audio.length) {
            // Had to stop early!
            // Write some more once it drains.
            ao.once('drain', write);
        }
    }
}

// utility function used by play func
function bufSplit(input){
    const result = [];
    input.forEach((b) => {
        // split buffer into two.
        result.push(b.slice(0, b.length / 2), b.slice(b.length / 2, b.length));
    });
    return result;
}

async function test() {
}

setTimeout(async () => {
    record = false;
    test()
}, 4000);

setTimeout(async () => {
    return;
}, 6000);