## Copyright (C) 2010-2015 David Bateman
##
## 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/>.

## -*- texinfo -*-
## @deftypefn {Function File} {[@var{hplots}, @var{strings}] =} __getlegenddata__ (@var{h})
## Undocumented internal function.
## @end deftypefn

function [hplots, text_strings] = __getlegenddata__ (hlegend)

  hplots = [];
  text_strings = {};
  ca = getfield (get (hlegend, "userdata"), "handle");
  if (numel (ca) == 1)
    kids = get (ca, "children");
    kids = {kids};
  else
    kids = get (ca, "children");
  endif

  for i = 1 : numel (kids)
    for ii = numel (kids{i}) : -1 : 1
      typ = get (kids{i}(ii), "type");
      if (any (strcmp (typ, {"line", "patch", "surface", "hggroup"})))
        if (strcmp (typ, "hggroup"))
          hgkids = get (kids{i}(ii), "children");
          for j = 1 : length (hgkids)
            try
              dname = get (hgkids(j), "DisplayName");
              if (! isempty (dname))
                hplots(end+1) = hgkids(j);
                text_strings(end+1) = dname;
                break;  # break from j-loop over hgkids
              endif
            end_try_catch
          endfor
        else
          dname = get (kids{i}(ii), "DisplayName");
          if (! isempty (dname))
            hplots(end+1) = kids{i}(ii);
            text_strings(end+1) = dname;
          endif
        endif
      endif
    endfor
  endfor

endfunction


## No test needed for internal helper function.
%!assert (1)

