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## -*- texinfo -*-
## @deftypefn  {} {@var{player} =} audioplayer (@var{y}, @var{fs})
## @deftypefnx {} {@var{player} =} audioplayer (@var{y}, @var{fs}, @var{nbits})
## @deftypefnx {} {@var{player} =} audioplayer (@var{y}, @var{fs}, @var{nbits}, @var{id})
## @deftypefnx {} {@var{player} =} audioplayer (@var{recorder})
## @deftypefnx {} {@var{player} =} audioplayer (@var{recorder}, @var{id})
## Create an audioplayer object that will play back data @var{y} at sample
## rate @var{fs}.
##
## The signal @var{y} can be a vector (mono audio) or a two-dimensional array
## (multi-channel audio).
##
## The optional arguments @var{nbits} and @var{id} specify the number of bits
## per sample and player device ID, respectively.  Device IDs may be found
## using the @code{audiodevinfo} function.
##
## Given an audiorecorder object @var{recorder}, use the data from the object
## to initialize the player.
##
## The list of actions for an audioplayer object are shown below.  All
## methods require an audioplayer object as the first argument.
##
## @multitable @columnfractions 0.2 0.75
## @headitem Method @tab Description
## @item get @tab Read audioplayer property values
## @item isplaying @tab Return true if audioplayer is playing
## @item pause @tab Pause audioplayer playback
## @item play @tab Play audio stored in audioplayer object w/o blocking
## @item playblocking @tab Play audio stored in audioplayer object
## @item resume @tab Resume playback after pause
## @item set @tab Write audioplayer property values
## @item stop @tab Stop playback
## @end multitable
##
## Example
##
## Create an audioplayer object that will play back one second of white noise
## at 44100 sample rate using 8 bits per sample.
##
## @example
## @group
## y = 0.25 * randn (2, 44100);
## player = audioplayer (y, 44100, 8);
## play (player);
## @end group
## @end example
## @seealso{@audioplayer/get, @audioplayer/isplaying, @audioplayer/pause,
## @audioplayer/play, @audioplayer/playblocking, @audioplayer/resume,
## @audioplayer/set, @audioplayer/stop, audiodevinfo,
## @audiorecorder/audiorecorder, sound, soundsc}
## @end deftypefn

function player = audioplayer (varargin)

  if (nargin < 1 || nargin > 4)
    print_usage ();
  endif

  if (isa (varargin{1}, "audiorecorder"))
    if (nargin == 1)
      player = getplayer (varargin{1});
    elseif (nargin == 2)
      recorder = varargin{1};
      data = getaudiodata (recorder);
      player = audioplayer (data,
                            get (recorder, "SampleRate"),
                            get (recorder, "BitsPerSample"),
                            varargin{2});
    else
      print_usage ();
    endif
  else
    ## FIXME: There is incomplete input validation in internal C++ function.
    ##        All validation should occur here in m-file.
    if (isempty (varargin{1}))
      error ("audioplayer: Y must be non-empty numeric data");
    endif
    player.player = __player_audioplayer__ (varargin{:});
    player = class (player, "audioplayer");
  endif

endfunction


%!demo
%! ## Generate 2 seconds of white noise and play it back with a pause
%! fs = 44100;
%! audio = 0.25 * randn (2, 2*fs);
%! player = audioplayer (audio, fs);
%! play (player);
%! pause (1);
%! pause (player);
%! pause (1);
%! resume (player);
%! pause (1);
%! stop (player);

## Tests of audioplayer must not actually play anything.

%!testif HAVE_PORTAUDIO; audiodevinfo (0) > 0
%! mono = 0.25 * randn (1, 44100);
%! stereo = 0.25 * randn (2, 44100);
%! fs = 44100;
%! player1 = audioplayer (mono, fs);
%! player2 = audioplayer (stereo, fs);
%! assert (player1.NumberOfChannels, 1);
%! assert (player2.NumberOfChannels, 2);
%! assert (player1.SampleRate, 44100);
%! assert (player2.SampleRate, 44100);
%! assert (player1.TotalSamples, 44100);
%! assert (player2.TotalSamples, 44100);

%!testif HAVE_PORTAUDIO; audiodevinfo (0) > 0
%! audio = randn (8000, 1);
%! fs = 44100;
%! player = audioplayer (audio, fs, 16);
%! assert (player.NumberOfChannels, 1);
%! assert (player.SampleRate, 44100);
%! assert (player.BitsPerSample, 16);

## Verify input validation
%!testif HAVE_PORTAUDIO; audiodevinfo (0) > 0
%! ## Verify nbits option only accepts 8, 16, 24
%! fail ("audioplayer (1, 8e3, 9)", "NBITS must be 8, 16, or 24");
%! fail ("audioplayer (1, 8e3, 32)", "NBITS must be 8, 16, or 24");
%! player = audioplayer (1, 8e3, 8);
%! player = audioplayer (1, 8e3, 16);
%! player = audioplayer (1, 8e3, 24);

%!error <Y must be non-empty numeric data> audioplayer ([])
