!7

import static x30_pkg.x30_util.VF1;

module LiveFFT > DynImageSurface {
  volatile bool enabled = true;
  transient int windowSize = 2; // seconds
  transient Q q;
  transient new L<short[]> buffer;
  transient int bufferSize, neededSamples;
  
  enhanceFrame {
    dm_intFieldMenuItem(f, 'windowSize, formTitle := "Window Size (Seconds)");
  }

  visualize {
    ret centerAndSouthWithMargins(super.visualize(),
      jrightalignedline(dm_fieldCheckBox('enabled)));
  }

  start {
    neededSamples = windowSize*44100;
    
    q = dm_startQ();
    dm_addAudioListener(voidfunc(short[] data) {
      if (!enabled) ret;
      buffer.add(mixStereoShortArrayToMono(data));
      bufferSize += l(data)/2;
      
      if (bufferSize >= neededSamples) {
        bufferSize -= neededSamples;
        final L<short[]> salvaged = cloneList(buffer);
        buffer.clear();
        if (bufferSize > 0) {
          buffer.add(lastNShorts(bufferSize, last(salvaged)));
          replaceLastElement(salvaged, dropLastNShorts(bufferSize, last(salvaged)));
        }
        q.add(r {
          MultiShortArrayInputStream_resettable stream = new(salvaged);
          stream.bigEndian = true;
          Clip clip = spectro_clipFromMonoInputStream(stream);
          setImage(clipToFrequencyImage(clip));
        });
      }
    });
  }  
}