/*

Copyright (C) 2013 Vytautas Jančauskas

This file is part of Octave.

Octave 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.

Octave 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 Octave; see the file COPYING.  If not, see
<http://www.gnu.org/licenses/>.

*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "oct.h"
#include "ov-struct.h"
#ifdef HAVE_SNDFILE
#include <sndfile.h>
#endif

DEFUN_DLD (audioread, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Loadable Function} {[@var{y}, @var{fs}] =} audioread (@var{filename})\n\
\n\
Load an audio file that is specified by @var{filename}.  It will be loaded\n\
in to a column matrix with as many rows as there are audio frames and as many\n\
columns as there are channels in the file.  Sampling rate will be stored in\n\
@var{fs}.\n\
\n\
@end deftypefn\n\
@deftypefn {Loadable Function} {[@var{y}, @var{fs}] =} audioread (@var{filename}, @var{samples})\n\
\n\
Read a specified range of samples from a file specified by @var{filename}.\n\
Argument @var{samples} is a vector with two values specifying starting frame\n\
and ending frame.\n\
\n\
@end deftypefn\n\
@deftypefn {Loadable Function} {[@var{y}, @var{fs}] =} audioread (@var{filename}, @var{datatype})\n\
\n\
Read a file and return an array of specified type.  If @var{datatype} is\n\
@qcode{\"native\"} then an array of fixed width integer type will be returned\n\
depending on how data is stored in the audio file.  If @var{datatype} is\n\
@qcode{\"double\"} a double matrix will be returned.\n\
\n\
@end deftypefn\n\
@deftypefn {Loadable Function} {[@var{y}, @var{fs}] =} audioread (@var{filename}, @var{samples}, @var{datatype})\n\
\n\
Read a file and return a specified range of frames in an array of specified type.\n\
\n\
@end deftypefn"
)
{
  octave_value_list retval;
#ifdef HAVE_SNDFILE
  Matrix audio;
  octave_value ret_audio;
  SNDFILE *file;
  SF_INFO info;
  info.format = 0;
  int start, end;
  file = sf_open (args(0).string_value ().c_str (), SFM_READ, &info);
  start = 0;
  end = info.frames;
  float *data = (float *)malloc (sizeof (float) * info.frames * info.channels);
  sf_read_float (file, data, info.frames * info.channels);
  if (args.length () == 2 && !args(1).is_string () || args.length () == 3)
    {
      RowVector range = args(1).row_vector_value ();
      start = range(0);
      end = range(1);
    }
  audio.resize (end - start, info.channels);
  for (int i = start; i < end; i++)
    {
      for (int channel = 0; channel < info.channels; channel++)
        {
          audio(i - start, channel) = data[i * info.channels + channel];
        }
    }
  free (data);
  if (args.length () == 2 && args(1).is_string () || args.length () == 3)
    {
      std::string type;
      if (args.length () == 3)
        type = args(2).string_value ();
      else
        type = args(1).string_value ();

      if (type == "native")
        {
          if (info.format & SF_FORMAT_PCM_S8)
            ret_audio = octave_value ((audio * 127)).int8_array_value ();
          else if (info.format & SF_FORMAT_PCM_U8)
            ret_audio = octave_value ((audio * 127 + 127)).uint8_array_value ();
          else if (info.format & SF_FORMAT_PCM_16)
            ret_audio = octave_value ((audio * 32767)).int16_array_value ();
          else if (info.format & SF_FORMAT_PCM_24)
            ret_audio = octave_value ((audio * 8388608)).int32_array_value ();
          else if (info.format & SF_FORMAT_PCM_32)
            ret_audio = octave_value ((audio * 2147483648)).int32_array_value ();
          else
            ret_audio = octave_value (audio);
        }
      else
        ret_audio = octave_value (audio);
    }
  else
    ret_audio = octave_value (audio);

  retval(0) = ret_audio;
  retval(1) = info.samplerate;
#else
  error ("sndfile not found on your system and thus audioread is not functional");
#endif
  return octave_value (retval);
}