/*
  Copyright (C) 2012 Paul Brossier <piem@aubio.org>

  This file is part of aubio.

  aubio is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  aubio is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with aubio.  If not, see <http://www.gnu.org/licenses/>.

*/

#ifdef __APPLE__
#include "config.h"
#include "aubio_priv.h"
#include "fvec.h"
#include "io/source_apple_audio.h"

// ExtAudioFileRef, AudioStreamBasicDescription, AudioBufferList, ...
#include <AudioToolbox/AudioToolbox.h>

#define RT_BYTE1( a )      ( (a) & 0xff )
#define RT_BYTE2( a )      ( ((a) >> 8) & 0xff )
#define RT_BYTE3( a )      ( ((a) >> 16) & 0xff )
#define RT_BYTE4( a )      ( ((a) >> 24) & 0xff )

#define SHORT_TO_FLOAT(x) (smpl_t)(x * 3.0517578125e-05)

struct _aubio_source_apple_audio_t {
  uint_t channels;
  uint_t samplerate;
  uint_t block_size;

  char_t *path;

  ExtAudioFileRef audioFile;
  AudioBufferList bufferList;
};

extern int createAubioBufferList(AudioBufferList *bufferList, int channels, int segmentSize);
extern void freeAudioBufferList(AudioBufferList *bufferList);
extern CFURLRef getURLFromPath(const char * path);

aubio_source_apple_audio_t * new_aubio_source_apple_audio(char_t * path, uint_t samplerate, uint_t block_size)
{
  aubio_source_apple_audio_t * s = AUBIO_NEW(aubio_source_apple_audio_t);

  s->path = path;
  s->block_size = block_size;
  s->channels = 1;

  OSStatus err = noErr;
  UInt32 propSize;

  // open the resource url
  CFURLRef fileURL = getURLFromPath(path);
  err = ExtAudioFileOpenURL(fileURL, &s->audioFile);
  if (err) { AUBIO_ERR("error when trying to access %s, in ExtAudioFileOpenURL, %d\n", s->path, (int)err); goto beach;}

  // create an empty AudioStreamBasicDescription
  AudioStreamBasicDescription fileFormat;
  propSize = sizeof(fileFormat);
  memset(&fileFormat, 0, sizeof(AudioStreamBasicDescription));

  // fill it with the file description
  err = ExtAudioFileGetProperty(s->audioFile,
      kExtAudioFileProperty_FileDataFormat, &propSize, &fileFormat);
  if (err) { AUBIO_ERROR("error in ExtAudioFileGetProperty, %d\n", (int)err); goto beach;}

  if (samplerate == 0) {
    samplerate = fileFormat.mSampleRate;
    //AUBIO_DBG("sampling rate set to 0, automagically adjusting to %d\n", samplerate);
  }
  s->samplerate = samplerate;

  AudioStreamBasicDescription clientFormat;
  propSize = sizeof(clientFormat);
  memset(&clientFormat, 0, sizeof(AudioStreamBasicDescription));
  clientFormat.mFormatID         = kAudioFormatLinearPCM;
  clientFormat.mSampleRate       = (Float64)(s->samplerate);
  clientFormat.mFormatFlags      = kAudioFormatFlagIsSignedInteger | kAudioFormatFlagIsPacked;
  clientFormat.mChannelsPerFrame = s->channels;
  clientFormat.mBitsPerChannel   = sizeof(short) * 8;
  clientFormat.mFramesPerPacket  = 1;
  clientFormat.mBytesPerFrame    = clientFormat.mBitsPerChannel * clientFormat.mChannelsPerFrame / 8;
  clientFormat.mBytesPerPacket   = clientFormat.mFramesPerPacket * clientFormat.mBytesPerFrame;
  clientFormat.mReserved         = 0;

  // set the client format description
  err = ExtAudioFileSetProperty(s->audioFile, kExtAudioFileProperty_ClientDataFormat,
      propSize, &clientFormat);
  if (err) { AUBIO_ERROR("error in ExtAudioFileSetProperty, %d\n", (int)err); goto beach;}

#if 0
  // print client and format descriptions
  AUBIO_DBG("Opened %s\n", s->path);
  AUBIO_DBG("file/client Format.mFormatID:        : %3c%c%c%c / %c%c%c%c\n",
      (int)RT_BYTE4(fileFormat.mFormatID),   (int)RT_BYTE3(fileFormat.mFormatID),   (int)RT_BYTE2(fileFormat.mFormatID),   (int)RT_BYTE1(fileFormat.mFormatID),
      (int)RT_BYTE4(clientFormat.mFormatID), (int)RT_BYTE3(clientFormat.mFormatID), (int)RT_BYTE2(clientFormat.mFormatID), (int)RT_BYTE1(clientFormat.mFormatID)
      );

  AUBIO_DBG("file/client Format.mSampleRate       : %6.0f / %.0f\n",     fileFormat.mSampleRate      ,      clientFormat.mSampleRate);
  AUBIO_DBG("file/client Format.mFormatFlags      : %6d / %d\n",    (int)fileFormat.mFormatFlags     , (int)clientFormat.mFormatFlags);
  AUBIO_DBG("file/client Format.mChannelsPerFrame : %6d / %d\n",    (int)fileFormat.mChannelsPerFrame, (int)clientFormat.mChannelsPerFrame);
  AUBIO_DBG("file/client Format.mBitsPerChannel   : %6d / %d\n",    (int)fileFormat.mBitsPerChannel  , (int)clientFormat.mBitsPerChannel);
  AUBIO_DBG("file/client Format.mFramesPerPacket  : %6d / %d\n",    (int)fileFormat.mFramesPerPacket , (int)clientFormat.mFramesPerPacket);
  AUBIO_DBG("file/client Format.mBytesPerFrame    : %6d / %d\n",    (int)fileFormat.mBytesPerFrame   , (int)clientFormat.mBytesPerFrame);
  AUBIO_DBG("file/client Format.mBytesPerPacket   : %6d / %d\n",    (int)fileFormat.mBytesPerPacket  , (int)clientFormat.mBytesPerPacket);
  AUBIO_DBG("file/client Format.mReserved         : %6d / %d\n",    (int)fileFormat.mReserved        , (int)clientFormat.mReserved);
#endif

  // compute the size of the segments needed to read the input file
  UInt32 samples = s->block_size * clientFormat.mChannelsPerFrame;
  Float64 rateRatio = clientFormat.mSampleRate / fileFormat.mSampleRate;
  uint_t segmentSize= (uint_t)(samples * rateRatio + .5);
  if (rateRatio < 1.) {
    segmentSize = (uint_t)(samples / rateRatio + .5);
  } else if (rateRatio > 1.) {
    AUBIO_WRN("up-sampling %s from %0.2fHz to %0.2fHz\n", s->path, fileFormat.mSampleRate, clientFormat.mSampleRate);
  } else {
    assert (segmentSize == samples );
    //AUBIO_DBG("not resampling, segmentSize %d, block_size %d\n", segmentSize, s->block_size);
  }

  // allocate the AudioBufferList
  if (createAubioBufferList(&s->bufferList, s->channels, segmentSize)) err = -1;

  return s;
 
beach:
  AUBIO_FREE(s);
  return NULL;
}

void aubio_source_apple_audio_do(aubio_source_apple_audio_t *s, fvec_t * read_to, uint_t * read) {
  UInt32 c, v, loadedPackets = s->block_size;
  OSStatus err = ExtAudioFileRead(s->audioFile, &loadedPackets, &s->bufferList);
  if (err) { AUBIO_ERROR("error in ExtAudioFileRead, %d\n", (int)err); goto beach;}

  smpl_t *buf = read_to->data;

  short *data = (short*)s->bufferList.mBuffers[0].mData;

  if (buf) {
      for (c = 0; c < s->channels; c++) {
          for (v = 0; v < s->block_size; v++) {
              if (v < loadedPackets) {
                  buf[v * s->channels + c] =
                      SHORT_TO_FLOAT(data[ v * s->channels + c]);
              } else {
                  buf[v * s->channels + c] = 0.f;
              }
          }
      }
  }
  //if (loadedPackets < s->block_size) return EOF;
  *read = (uint_t)loadedPackets;
  return;
beach:
  *read = 0;
  return;
}

void del_aubio_source_apple_audio(aubio_source_apple_audio_t * s){
  OSStatus err = noErr;
  if (!s || !s->audioFile) { return; }
  err = ExtAudioFileDispose(s->audioFile);
  if (err) AUBIO_ERROR("error in ExtAudioFileDispose, %d\n", (int)err);
  s->audioFile = NULL;
  freeAudioBufferList(&s->bufferList);
  AUBIO_FREE(s);
  return;
}

uint_t aubio_source_apple_audio_get_samplerate(aubio_source_apple_audio_t * s) {
  return s->samplerate;
}

#endif /* __APPLE__ */