# Copyright (C) 2004  Alex Schroeder <alex@emacswiki.org>
#
# This program 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.
#
# This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

# In your CSS file, use something like this, for example:

# span[lang=en] { background-color:#ddf; }
# span[lang=fr] { background-color:#fdd; }
# span[lang=de] { background-color:#ffd; }
# span[lang=it] { background-color:#dfd; }

use strict;
use v5.10;

AddModuleDescription('lang.pl', 'Language Extension');

our ($q, @HtmlStack, @MyRules, $FullUrl);

push(@MyRules, \&LangRule);

sub LangRule {
  if  (m/\G\[([a-z][a-z])\]/cg) {
    my $html;
    $html .= "</" . shift(@HtmlStack) . ">"  if $HtmlStack[0] eq 'span';
    return $html . AddHtmlEnvironment('span', "lang=\"$1\"") . "[$1]";
  }
  return;
}

*OldLangInitCookie = \&InitCookie;
*InitCookie = \&NewLangInitCookie;

sub NewLangInitCookie {
  OldLangInitCookie(@_);
  if ($q->param('setlang')) {
    my @old = split(/ /, GetParam('theme', ''));
    my @old_normal;
    my @old_languages;
    foreach my $entry (@old) {
      if (length($entry) == 2) {
	push(@old_languages, $entry);
      } else {
	push(@old_normal, $entry);
      }
    }
    my @new = $q->param('languages');
    SetParam('theme', join(' ', @old_normal, @new));
  }
}

*OldLangGetNearLinksUsed = \&GetNearLinksUsed;
*GetNearLinksUsed = \&NewLangGetNearLinksUsed;

sub NewLangGetNearLinksUsed {
  my $id = shift;
  my $html = OldLangGetNearLinksUsed($id);
  my @langs = qw(en de fr it pt);
  my @selected = split(/ /, GetParam('theme', '')); # may contain elements that are not in @langs!
  $html .= $q->div({-class=>'languages'}, "<form action='$FullUrl'>",
		   $q->p(GetHiddenValue('action', 'browse'),
			 GetHiddenValue('id', $id),
			 T('Languages:'), ' ',
			 $q->checkbox_group('languages', \@langs, \@selected),
			 $q->hidden('setlang', '1'),
			 $q->submit('dolang', T('Show!'))),
		  '</form>');
  return $html;
}