!7

// TODO: pause while speaking

module ListenOnNoise > DynPrintLogAndEnabled {
  double minLevel = 20; // percent
  double maxPause = 1; // pause allowed while we keep recording, seconds
  double minDuration = 0.6; // min seconds of complete recording to submit
  double maxDuration = 10; // always stop after this many seconds
  
  transient int interval = 100;
  transient long noiseSince, lastNoise;
  transient L<short[]> buffer = synchroList();
  
  start {
    dm_addAudioListener(voidfunc(short[] data) {
      if (noiseSince == 0) clear(buffer);
      buffer.add(cloneShortArray(data));
    });
 
    doEvery(interval, r {
      if (noiseSince != 0 && elapsedSeconds(noiseSince) >= maxDuration-0.05) {
        // too long, discard, maybe it's constant noise
        print("Recording too long (" + maxDuration + " s), discarding");
        noiseSince = 0;
        clear(buffer);
      }
      
      float volume = dm_inputVolumeLevel();
      //print("Volume: " + volume);
      if (volume >= minLevel) {
        // got noise
        lastNoise = sysNow();
        if (noiseSince == 0)
          noiseSince = lastNoise;
      } else if (noiseSince != 0) { // got no noise, but am recording
        if (elapsedSeconds(lastNoise) > maxPause-0.05) {
          double duration = toSeconds(lastNoise-noiseSince+250);
          if (duration >= minDuration-0.05) {
            print("Keeping recording of " + formatDouble(duration, 1) + " seconds");
            if (enabled) {
              L<short[]> chunks = cloneList(buffer);
              
              // drop last silent chunks
              int len = lengthLevel2_shortArrays(chunks);
              int wantedLengthInSamples = iround(duration*44100*2);
              int dropped = 0;
              while (len-l(last(chunks)) >= wantedLengthInSamples) {
                len -= l(last(chunks));
                popLast(chunks);
                ++dropped;
              }
              //print("Dropped " + n2(dropped, "chunk"));
              
              File wavFile = anonymousWAVEFile();
              multiShortArraysToWAVE(chunks, wavFile);
              //printFileInfo(wavFile);
              vmBus_send('newRecording, wavFile);
            }
          } else
            print("Discarding recording of " + formatDouble(duration, 1) + " seconds");
          noiseSince = 0;
          clear(buffer);
        }
      }
    });
  }
}