########################################################################
##
## Copyright (C) 1999-2020 The Octave Project Developers
##
## See the file COPYRIGHT.md in the top-level directory of this
## distribution or <https://octave.org/copyright/>.
##
## 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
## <https://www.gnu.org/licenses/>.
##
########################################################################

## -*- texinfo -*-
## @deftypefn {} {} __gnuplot_print__ (@var{@dots{}})
## Undocumented internal function.
## @end deftypefn

function opts = __gnuplot_print__ (opts)

  dos_shell = (ispc () && ! isunix ());

  if (isempty (opts.fontsize))
    ## If no fontsize, determine the nominal axes fontsize.
    defaultfontsize = get (0, "defaultaxesfontsize");
    axesfontsize = get (findobj (opts.figure, "type", "axes"), "fontsize");
    if (iscell (axesfontsize))
      axesfontsize = round (median (cell2mat (axesfontsize)));
    endif
    if (isempty (axesfontsize))
      opts.fontsize = defaultfontsize;
    else
      opts.fontsize = axesfontsize;
    endif
  endif
  ## The axes-label and tick-label spacing is determined by
  ## the font spec given in "set terminal ..."
  gp_opts = font_spec (opts);
  if (! any (strcmpi (opts.devopt, {"fig", "dxf", "hpgl", "mf", "pstricks", ...
                                    "texdraw", "latex", "eepic"})))
    bg = get (opts.figure, "color");
    if (isnumeric (bg))
      gp_opts = sprintf ('%s background rgb "#%02x%02x%02x"',
                         gp_opts, round (255 * bg));
    else
      gp_opts = sprintf ("%s nobackground", gp_opts);
    endif
  endif

  pipeline = "";

  switch (lower (opts.devopt))
    case {"eps", "eps2", "epsc", "epsc2"}
      if (any (strcmp (opts.devopt, {"eps", "epsc"})))
        gp_opts = [gp_opts " level1"];
      endif
      if (opts.tight || ! isempty (opts.preview))
        tmp_file = [tempname() ".eps"];
        eps_drawnow (opts, tmp_file, gp_opts);
        if (dos_shell)
          cleanup = [" & del " strrep(tmp_file, '/', '\')];
        else
          cleanup = [" ; rm " tmp_file];
        endif
        pipeline = {sprintf("%s %s",
                            opts.epstool_cmd (opts, tmp_file, opts.name),
                            cleanup)};
      else
        eps_drawnow (opts, opts.name, gp_opts);
      endif
    case {"epslatex", "pslatex", "pstex", "epslatexstandalone"}
      dot = find (opts.name == ".", 1, "last");
      n = find (opts.devopt == "l", 1);
      suffix = opts.devopt(1:n-1);
      [ndir, name, ext] = fileparts (opts.name);
      if (isempty (ext))
        ext = "tex";
      else
        ext = ext(2:end);  # remove leading '.'
      endif
      if (any (strcmpi (ext, {suffix, "tex"})))
        name = fullfile (ndir, name);
        if (any (strcmpi (ext, {"eps", "ps", "pdf"})))
          suffix = ext;  # If user provides eps/ps/pdf suffix, use it.
        endif
      else
        error ("Octave:print:invalid-suffix",
               "invalid suffix '%s' for device '%s'.",
               ext, lower (opts.devopt));
      endif
      suffix = "tex";
      if (strfind (opts.devopt, "standalone"))
        gp_opts = sprintf ("standalone %s", gp_opts);
        term = strrep (opts.devopt, "standalone", "");
      else
        term = sprintf ("%s ", opts.devopt);
      endif
      local_drawnow ([term " " gp_opts],
                     [name "." suffix], opts);
    case {"tikz", "tikzstandalone"}
      if (strfind (opts.devopt, "standalone"))
        gp_opts = sprintf ("standalone %s", gp_opts);
      endif
      if (__gnuplot_has_terminal__ ("tikz"))
        local_drawnow (["tikz " gp_opts], opts.name, opts);
      else
        error (sprintf ("print:no%soutput", opts.devopt),
               "print: '%s' output is not available for gnuplot-%s",
               upper (opts.devopt), __gnuplot_version__ ());
      endif
    case "svg"
      local_drawnow (["svg dynamic " gp_opts], opts.name, opts);
    case {"eepic"}
      local_drawnow ([opts.devopt " color rotate " gp_opts], opts.name, opts);
    case {"aifm", "corel", "emf", "fig"}
      local_drawnow ([opts.devopt " " gp_opts], opts.name, opts);
    case {"cairolatex", "epscairo", "epscairolatex", ...
          "epscairolatexstandalone", "pdfcairo", "pdfcairolatex", ...
          "pdfcairolatexstandalone", "pngcairo", ...
          "pdflatexstandalone", "pdflatex"}
      term = opts.devopt;
      if (strfind (term, "standalone"))
        gp_opts = sprintf ("standalone %s", gp_opts);
        term = strrep (term, "standalone", "");
      endif
      if (strfind (term, "epscairolatex"))
        gp_opts = sprintf ("eps %s", gp_opts);
        term = strrep (term, "epscairolatex", "cairolatex");
      elseif (strfind (term, "pdfcairolatex") || strfind (term, "pdflatex"))
        gp_opts = sprintf ("pdf %s", gp_opts);
        term = strrep (term, "pdfcairolatex", "cairolatex");
        term = strrep (term, "pdflatex", "cairolatex");
      endif
      if (__gnuplot_has_terminal__ (term))
        local_drawnow ([term " " gp_opts], opts.name, opts);
      else
        error (sprintf ("print:no%soutput", opts.devopt),
               "print: '%s' output is not available for gnuplot-%s",
               upper (opts.devopt), __gnuplot_version__ ());
      endif
    case {"canvas", "cgm", "dxf", "hpgl", "latex", "mf", "gif", ...
          "pstricks", "texdraw"}
      if (__gnuplot_has_terminal__ (opts.devopt))
        local_drawnow ([opts.devopt " " gp_opts], opts.name, opts);
      else
        error (sprintf ("print:no%soutput", opts.devopt),
               "print: '%s' output is not available for gnuplot-%s",
               upper (opts.devopt), __gnuplot_version__ ());
      endif
    case "dumb"
      local_drawnow ("dumb size 72,24", opts.name, opts);
    case opts.ghostscript.device
      gp_opts = font_spec (opts, "devopt", "eps");
      opts.ghostscript.output = opts.name;
      opts.ghostscript.source = [tempname() ".eps"];
      eps_drawnow (opts, opts.ghostscript.source, gp_opts);
      [cmd_gs, cmd_cleanup] = __ghostscript__ (opts.ghostscript);
      if (opts.send_to_printer || isempty (opts.name))
        cmd_lpr = opts.lpr_cmd (opts);
        cmd = [cmd_gs " | " cmd_lpr];
      else
        cmd = cmd_gs;
      endif
      if (dos_shell)
        cmd = sprintf ("%s & del %s", cmd,
                       strrep (opts.ghostscript.source, '/', '\'));
      else
        cmd = sprintf ("%s ; rm %s", cmd, opts.ghostscript.source);
      endif
      if (! isempty (cmd_cleanup))
        if (dos_shell)
          pipeline = {[cmd " & " cmd_cleanup]};
        else
          pipeline = {[cmd " ; " cmd_cleanup]};
        endif
      else
        pipeline = {cmd};
      endif
    otherwise
      error (sprintf ("print:no%soutput", opts.devopt),
             "print: %s output is not available for the Gnuplot graphics toolkit",
             upper (opts.devopt));
  endswitch


  opts.pipeline = pipeline;

  for n = 1:numel (pipeline)
    if (opts.debug)
      fprintf ("gnuplot-pipeline: '%s'\n", pipeline{n});
    endif
    [status, output] = system (pipeline{n});
    if (status)
      fprintf ("%s\n%s\n%s\n",
               "---------- output begin ----------",
               output,
               "----------- output end -----------");
      error ("Octave:gnuplot:failedpipe", "print: failed to print");
    endif
  endfor

endfunction


function eps_drawnow (opts, epsfile, gp_opts)

  [h, fontsize] = get_figure_text_objs (opts);
  unwind_protect
    fontsize_2x = cellfun (@times, {2}, fontsize, "uniformoutput", false);
    set (h, {"fontsize"}, fontsize_2x);
    local_drawnow (["postscript eps " gp_opts], epsfile, opts);
  unwind_protect_cleanup
    set (h, {"fontsize"}, fontsize);
  end_unwind_protect

endfunction


function local_drawnow (term, file, opts)

  set (0, "currentfigure", opts.figure);
  if (isempty (opts.debug_file) || ! opts.debug)
    drawnow (term, file);
  else
    drawnow (term, file, opts.debug_file);
  endif
  if (opts.debug)
    fprintf ("Expanded gnuplot terminal = '%s'\n", term);
  endif

endfunction


function f = font_spec (opts, varargin)
  for n = 1:2:numel (varargin)
    opts.(varargin{n}) = varargin{n+1};
  endfor
  f = "";
  switch (opts.devopt)
    case "cgm"
      if (! isempty (opts.font) && ! isempty (opts.fontsize))
        f = sprintf ('font "%s,%d"', opts.font, opts.fontsize);
      elseif (! isempty (opts.font))
        f = sprintf ('font "%s"', opts.font);
      elseif (! isempty (opts.fontsize))
        f = sprintf ('font ",%d"', opts.fontsize);
      endif
    case {"eps", "eps2", "epsc", "epsc2"}
      ## Gnuplot renders fonts as half their specification, which
      ## results in a tight spacing for the axes-labels and tick-labels.
      ## Compensate for the half scale.  This will produce the proper
      ## spacing for the requested fontsize.
      if (! isempty (opts.font) && ! isempty (opts.fontsize))
        f = sprintf ('font "%s,%d"', opts.font, 2 * opts.fontsize);
      elseif (! isempty (opts.font))
        f = sprintf ('font "%s"', opts.font);
      elseif (! isempty (opts.fontsize))
        f = sprintf ('font ",%d"', 2 * opts.fontsize);
      endif
    case "svg"
      if (! isempty (opts.font) && ! isempty (opts.fontsize))
        f = sprintf ('font "%s,%d"', opts.font, opts.fontsize * 0.75);
      elseif (! isempty (opts.font))
        f = sprintf ('font "%s"', opts.font);
      elseif (! isempty (opts.fontsize))
        f = sprintf ('font ",%d"', opts.fontsize * 0.75);
      endif
    case "pdf"
      if (! isempty (opts.font) && ! isempty (opts.fontsize))
        f = sprintf ('font "%s,%d"', opts.font, opts.fontsize);
      elseif (! isempty (opts.font))
        f = sprintf ('font "%s"', opts.font);
      elseif (! isempty (opts.fontsize))
        f = sprintf ('font ",%d"', opts.fontsize);
      endif
    case {"cairolatex", "epscairo", "epscairolatex", ...
          "epscairolatexstandalone", "pdfcairo", "pdfcairolatex", ...
          "pdfcairolatexstandalone", "pngcairo", ...
          "pdflatexstandalone", "pdflatex"}
      if (! isempty (opts.font) && ! isempty (opts.fontsize))
        f = sprintf ('font "%s,%d"', opts.font, opts.fontsize);
      elseif (! isempty (opts.font))
        f = sprintf ('font "%s"', opts.font);
      elseif (! isempty (opts.fontsize))
        f = sprintf ('font ",%d"', opts.fontsize);
      endif
    case {"epslatex", "epslatexstandalone"}
      if (! isempty (opts.font) && ! isempty (opts.fontsize))
        f = sprintf ('font "%s,%d"', opts.font, opts.fontsize);
      elseif (! isempty (opts.font))
        f = sprintf ('font "%s"', opts.font);
      elseif (! isempty (opts.fontsize))
        f = sprintf ('font ",%d"', opts.fontsize);
      endif
    case "pslatex"
      if (! isempty (opts.fontsize))
        f = sprintf ("%d", opts.fontsize);
      endif
    case {"gif", "jpeg", "png"}
      if (! isempty (opts.font) && ! isempty (opts.fontsize))
        f = sprintf ('font "%s,%d"', opts.font, opts.fontsize);
      elseif (! isempty (opts.font))
        f = sprintf ('font "%s"', opts.font);
      elseif (! isempty (opts.fontsize))
        f = sprintf ('font ",%d"', opts.fontsize);
      endif
    case "emf"
      if (! isempty (opts.font) && ! isempty (opts.fontsize))
        f = sprintf ('font "%s,%d"', opts.font, opts.fontsize);
      elseif (! isempty (opts.font))
        f = sprintf ('font "%s"', opts.font);
      elseif (! isempty (opts.fontsize))
        f = sprintf ('font ",%d"', opts.fontsize);
      endif
    case "canvas"
      if (! isempty (opts.fontsize))
        f = sprintf ('font ",%d"', opts.fontsize);
      endif
    case {"aifm", "corel"}
      if (! isempty (opts.font) && ! isempty (opts.fontsize))
        f = sprintf ('font "%s,%d"', opts.font, opts.fontsize);
      elseif (! isempty (opts.font))
        f = sprintf ('font "%s"', opts.font);
      elseif (! isempty (opts.fontsize))
        f = sprintf ('font ",%d"', opts.fontsize);
      endif
    case "fig"
      if (! isempty (opts.font) && ! isempty (opts.fontsize))
        f = sprintf ('font "%s,%d"', opts.font, opts.fontsize);
      elseif (! isempty (opts.font))
        f = sprintf ('font "%s"', opts.font);
      elseif (! isempty (opts.fontsize))
        f = sprintf ('font ",%d"', opts.fontsize);
      endif
  endswitch

endfunction


function [h, fontsize] = get_figure_text_objs (opts)

  h = findall (opts.figure, "-property", "fontsize");
  hp = get (h, "parent");
  if (iscell (hp))
    hp = cell2mat (hp);
  endif
  ## Do not change the text objects fontsizes for the children of a
  ## legend axes.  These will be handled by the fontsize listener.
  is_legend_key_string = strcmp (get (hp, "tag"), "legend") ...
                         & strcmp (get (hp, "type"), "axes");
  h(is_legend_key_string) = [];
  fontsize = get (h, "fontsize");
  switch (numel (fontsize))
    case 0
      fontsize = {};
    case 1
      fontsize = {fontsize};
  endswitch

endfunction
