CodecHelix.h

#pragma once
 
#include "AudioCodecs/AudioEncoded.h"
#include "AudioCodecs/CodecWAV.h"
#include "AudioCodecs/CodecMP3Helix.h"
#include "AudioCodecs/CodecAACHelix.h"
 
namespace audio_tools {
 
class DecoderHelix : public AudioDecoder {
public:
  DecoderHelix() { TRACED(); }
 
  DecoderHelix(Print &out_stream) {
    TRACED();
    p_out_stream = &out_stream;
  }
 
  DecoderHelix(Print &out_stream, AudioInfoSupport &bi) {
    TRACED();
    p_out_stream = &out_stream;
    p_bi = &bi;
  }
 
  ~DecoderHelix() { resetDecoder(); }
 
  virtual void setOutput(Print &outStream) { p_out_stream = &outStream; }
 
  bool begin() {
    TRACED();
    // reset actual decoder so that we start a new determination
    resetDecoder();
    return true;
  }
 
  void end() {
    TRACED();
    if (p_decoder!=nullptr){
      p_decoder->end();
    }
    resetDecoder();
  }
 
  AudioInfo audioInfo() override {
    return p_decoder != nullptr ? p_decoder->audioInfo() : noInfo;
  }
 
  size_t write(const void *data, size_t len) {
    LOGD("%s: %zu", LOG_METHOD, len);
    if (p_decoder == nullptr) {
      setupDecoder((const byte *)data);
      p_decoder->begin();
    }
    return p_decoder->write(data, len);
  }
 
  operator bool() { return p_decoder == nullptr ? false : *p_decoder; }
 
protected:
  AudioDecoder *p_decoder = nullptr;
  Print *p_out_stream = nullptr;
  AudioInfoSupport *p_bi = nullptr;
  AudioInfo noInfo;
 
  void setupDecoder(const byte *start) {
    if (start[0] == 0xFF && start[1] == 0xF1) {
      p_decoder = new AACDecoderHelix();
      LOGI("using AACDecoderHelix");
    } else if (start[0] == 0xFF || start[0] == 0xFE || strncmp("ID3", (const char*)start, 3)==0) {
      p_decoder = new MP3DecoderHelix();
      LOGI("using MP3DecoderHelix");
    } else if (strncmp("RIFF", (const char*)start, 4)==0) {
      p_decoder = new WAVDecoder();
      LOGI("using WAVDecoder");
    }
    // if we do not have a decoder yet we use a dummy to prevent NPE
    if (p_decoder == nullptr) {
      LOGW("Unknown Data Format: Content will be ignored...")
      p_decoder = CodecNOP::instance();
    }
    p_decoder->setOutput(*p_out_stream);
    p_decoder->addNotifyAudioChange(*p_bi);
  }
 
  void resetDecoder() {
    if (p_decoder != nullptr) {
      delete p_decoder;
    }
    p_decoder = nullptr;
  }
};
 
} // namespace audio_tools