function [melody, elapsedTime]=stDsRead(dsDir, opt, showPlot)
% Read the dataset (DS) for singing transcription (ST)
%
%	Usage:
%		dataset=stDatasetRead(datasetDir);
%
%	Example:
%		dsDir='d:/dataSet/public/MIR-ST500';
%		[ds, time]=stDsRead(dsDir, [], 1);
%		fprintf('Time for reading "%s" = %g sec\n', dsDir, time);

%	Roger Jang, 20200618

if nargin<1, selfdemo; return; end
if ischar(dsDir) && strcmpi(dsDir, 'defaultOpt')    % Set the default options
	melody.junk=0;
	return
end
if nargin<2||isempty(opt), opt=feval(mfilename, 'defaultOpt'); end
if nargin<3, showPlot=0; end

myTic=tic;
%%
melody=dir(dsDir);
melody=melody([melody.isdir]);
melody(1:2)=[];		% Get rid of "." and ".."
melodyCount=length(melody);
%%
for i=1:melodyCount
	melody(i).songId=eval(melody(i).name);
end
[~, id]=sort([melody.songId]);
melody=melody(id);
%%
for i=1:melodyCount
	% Read the groundtruth
	melody(i).gtFile=fullfile(melody(i).folder, melody(i).name, sprintf('%d_groundtruth.txt', melody(i).songId));
	melody(i).noteGt=noteFileRead(melody(i).gtFile);	% Read the groundtruth file
	% Read the feature file
	melody(i).feaFile=fullfile(melody(i).folder, melody(i).name, sprintf('%d_feature.json', melody(i).songId));
	melody(i).fea=jsondecode(fileread(melody(i).feaFile));	% Read the feature file
	if showPlot, fprintf('%d/%d: gtFile=%s, feaFile=%s\n', i, melodyCount, melody(i).gtFile, melody(i).feaFile); end
end
%%
melody=rmfield(melody, 'isdir');
melody=rmfield(melody, 'date');
melody=rmfield(melody, 'datenum');
elapsedTime=toc(myTic);		% Elapsed time

% ====== Self demo
function selfdemo
mObj=mFileParse(which(mfilename));
strEval(mObj.example);