// This file is part of the 64k demo project.
// Experimental MP3 sample decoding via miniaudio (non-STRIP_ALL only).
// Compiles to nothing in stripped builds.

#include "mp3_sample.h"

#if !defined(STRIP_ALL)

// miniaudio.h is already compiled with MINIAUDIO_IMPLEMENTATION in audio.cc.
// Include here without it to get struct/function declarations only.
#include "miniaudio.h"

// Concrete definition (opaque to callers via header forward declaration).
struct Mp3Decoder {
  ma_decoder dec;
};

Mp3Decoder* mp3_open(const uint8_t* data, size_t size) {
  Mp3Decoder* d = new Mp3Decoder();
  ma_decoder_config cfg = ma_decoder_config_init(ma_format_f32, 1, 32000);
  if (ma_decoder_init_memory(data, size, &cfg, &d->dec) != MA_SUCCESS) {
    delete d;
    return nullptr;
  }
  return d;
}

int mp3_decode_range(Mp3Decoder* dec, int start_frame, int num_frames,
                     float* out) {
  if (ma_decoder_seek_to_pcm_frame(&dec->dec, (ma_uint64)start_frame) !=
      MA_SUCCESS) {
    return 0;
  }
  ma_uint64 frames_read = 0;
  ma_decoder_read_pcm_frames(&dec->dec, out, (ma_uint64)num_frames,
                             &frames_read);
  return (int)frames_read;
}

int mp3_decode(Mp3Decoder* dec, int num_frames, float* out) {
  ma_uint64 frames_read = 0;
  ma_decoder_read_pcm_frames(&dec->dec, out, (ma_uint64)num_frames,
                             &frames_read);
  return (int)frames_read;
}

void mp3_close(Mp3Decoder* dec) {
  if (!dec)
    return;
  ma_decoder_uninit(&dec->dec);
  delete dec;
}

#endif // !STRIP_ALL