%STRUC2CELL recursively converts a structure into a cell
%   
%   EXAMPLE: 
%
%     Define structure:
%       p = [];
%       p.verbose_level = 2;
%       p.energy = 6.2;
%       p.engines.engine0.name = 'DM';
%       p.engines.engine0.iter = 200;
%       
%     Convert to cell:
%       fn = struc2cell(p)
%
%     Output:
%        1×4 cell array
%           'verbose_level'  'energy'  'engines.engine0.name'  'engines.engine0.iter'
%

%*-----------------------------------------------------------------------*
%|                                                                       |
%|  Except where otherwise noted, this work is licensed under a          |
%|  Creative Commons Attribution-NonCommercial-ShareAlike 4.0            |
%|  International (CC BY-NC-SA 4.0) license.                             |
%|                                                                       |
%|  Copyright (c) 2017 by Paul Scherrer Institute (http://www.psi.ch)    |
%|                                                                       |
%|       Author: CXS group, PSI                                          |
%*-----------------------------------------------------------------------*
% You may use this code with the following provisions:
%
% If the code is fully or partially redistributed, or rewritten in another
%   computing language this notice should be included in the redistribution.
%
% If this code, or subfunctions or parts of it, is used for research in a 
%   publication or if it is fully or partially rewritten for another 
%   computing language the authors and institution should be acknowledged 
%   in written form in the publication: “Data processing was carried out 
%   using the “cSAXS matlab package” developed by the CXS group,
%   Paul Scherrer Institut, Switzerland.” 
%   Variations on the latter text can be incorporated upon discussion with 
%   the CXS group if needed to more specifically reflect the use of the package 
%   for the published work.
%
% A publication that focuses on describing features, or parameters, that
%    are already existing in the code should be first discussed with the
%    authors.
%   
% This code and subroutines are part of a continuous development, they 
%    are provided “as they are” without guarantees or liability on part
%    of PSI or the authors. It is the user responsibility to ensure its 
%    proper use and the correctness of the results.

function [entry] = struc2cell(data)


if ~isstruct(data)
    error('Expected structure as input data.')
else
    [entry] = rec_call(data);
end


end

function [entry] = rec_call(data)

fn = fieldnames(data);
en = [];
for ii=1:length(fn)
    while true
        try
            if ~isstruct(data.(fn{ii}))
                en{end+1} = fn{ii};
                break;
            else
                entry = rec_call(data.(fn{ii}));
                for jj=1:length(entry)
                    en{end+1} = [fn{ii} '.' entry{jj}];
                end
                break;
            end
        catch
            en{end+1} = fn{ii};
            break;
        end
    end
end
entry = en;


end