## Copyright (C) 2010-2012 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{style} =} __next_line_style__ (@var{reset})
## Undocumented internal function.
## @end deftypefn

## Return the next line style in the rotation.


function [linestyle, marker] = __next_line_style__ (reset)

  persistent reset_style = true;

  if (nargin > 1)
    print_usage ();
  endif

  if (nargin == 1)
    ## Indicates whether the next call will increment or not
    reset_style = reset;
  else
    ## Find and return the next line style
    ca = gca ();
    style_rotation = get (ca, "linestyleorder");
    if (ischar (style_rotation))
      style_rotation = strsplit (style_rotation, "|");
    endif
    nStyles = length (style_rotation);
    if (reset_style || (nStyles < 2))
      style_index = 1;
      reset_style = false;
    else
      ## Executed when "hold all" is active
      nChildren = length (get (ca, "Children"));
      nColors = length (get (ca, "ColorOrder"));
      style_index = mod (floor (nChildren/nColors), nStyles) + 1;
    endif
    options = __pltopt__ ("__next_line_style__",
                          style_rotation(style_index));
    linestyle = options.linestyle;
    marker = options.marker;
  endif

endfunction