#ifndef _AUDIO_H
#define _AUDIO_H

#include <Arduino.h>

#include "infra/I2S.h"

// 16bit, monoral, 16000Hz,  linear PCM
class Audio {
private:
  I2S* i2s;
  static const int _headerSize = 44;
  static const int _i2sBufferSize = 6000; // 22500
  char _i2sBuffer[_i2sBufferSize];
  char _i2sBuffer2[_i2sBufferSize];

  static const int _wavDataSize = 90000;                   // It must be multiple of _dividedWavDataSize. Recording time is about 1.9 second.
  static const int _dividedWavDataSize = _i2sBufferSize/4;
  char** _wavData;                                         // It's divided. Because large continuous memory area can't be allocated in esp32.

  static const int _prerecordedWavDataSize = _wavDataSize/4;
  char** _prerecordedWavData;

  byte _paddedHeader[_headerSize + 4] = {0};               // The size must be multiple of 3 for Base64 encoding. Additional byte size must be even because wave data is 16bit.

  unsigned long _startMicros = 0;

  void _writeToBuffer(char** wavBuffer, int waveDataSize);
  void _createWavHeader(byte* header, int waveDataSize);

public:
  Audio(MicType micType);
  ~Audio();
  char** record();
  int getSize();
  String print(Stream* stream);
  unsigned long getStartMicros();
  bool isNoiseDetected(int threshold);
};

#endif // _AUDIO_H