IkiWiki/Plugin/toc.pm

   1 #!/usr/bin/perl
   2 # Table Of Contents generator
   3 package IkiWiki::Plugin::toc;
   4
   5 use warnings;
   6 use strict;
   7 use IkiWiki;
   8 use HTML::Parser;
   9
  10 sub import { #{{{
  11         IkiWiki::hook(type => "preprocess", id => "toc",
  12                 call => \&preprocess);
  13         IkiWiki::hook(type => "format", id => "toc",
  14                 call => \&format);
  15 } # }}}
  16
  17 my %tocpages;
  18
  19 sub preprocess (@) { #{{{
  20         my %params=@_;
  21
  22         $params{levels}=1 unless exists $params{levels};
  23
  24         # It's too early to generate the toc here, so just record the
  25         # info.
  26         $tocpages{$params{destpage}}=\%params;
  27
  28         return "\n<div class=\"toc\"></div>\n";
  29 } # }}}
  30
  31 sub format (@) { #{{{
  32         my %params=@_;
  33         my $content=$params{content};
  34
  35         return $content unless exists $tocpages{$params{page}};
  36         %params=%{$tocpages{$params{page}}};
  37
  38         my $p=HTML::Parser->new(api_version => 3);
  39         my $page="";
  40         my $index="";
  41         my %anchors;
  42         my $curlevel;
  43         my $startlevel=0;
  44         my $liststarted=0;
  45         my $indent=sub { "\t" x $curlevel };
  46         $p->handler(start => sub {
  47                 my $tagname=shift;
  48                 my $text=shift;
  49                 if ($tagname =~ /^h(\d+)$/i) {
  50                         my $level=$1;
  51                         my $anchor="index".++$anchors{$level}."h$level";
  52                         $page.="$text<a name=\"$anchor\" />";
  53
  54                         # Take the first header level seen as the topmost level,
  55                         # even if there are higher levels seen later on.
  56                         if (! $startlevel) {
  57                                 $startlevel=$level;
  58                                 $curlevel=$startlevel-1;
  59                         }
  60                         elsif ($level < $startlevel) {
  61                                 $level=$startlevel;
  62                         }
  63
  64                         return if $level - $startlevel >= $params{levels};
  65
  66                         if ($level > $curlevel) {
  67                                 while ($level > $curlevel + 1) {
  68                                         $index.=&$indent."<ol>\n";
  69                                         $curlevel++;
  70                                         $index.=&$indent."<li class=\"L$curlevel\">\n";
  71                                 }
  72                                 $index.=&$indent."<ol>\n";
  73                                 $curlevel=$level;
  74                                 $liststarted=1;
  75                         }
  76                         elsif ($level < $curlevel) {
  77                                 while ($level < $curlevel) {
  78                                         $index.=&$indent."</li>\n" if $curlevel;
  79                                         $curlevel--;
  80                                         $index.=&$indent."</ol>\n";
  81                                 }
  82                                 $liststarted=0;
  83                         }
  84
  85                         $p->handler(text => sub {
  86                                 $page.=join("", @_);
  87                                 $index.=&$indent."</li>\n" unless $liststarted;
  88                                 $liststarted=0;
  89                                 $index.=&$indent."<li class=\"L$curlevel\">".
  90                                         "<a href=\"#$anchor\">".
  91                                         join("", @_).
  92                                         "</a>\n";
  93                                 $p->handler(text => undef);
  94                         }, "dtext");
  95                 }
  96                 else {
  97                         $page.=$text;
  98                 }
  99         }, "tagname, text");
 100         $p->handler(default => sub { $page.=join("", @_) }, "text");
 101         $p->parse($content);
 102         $p->eof;
 103
 104         while ($startlevel && $curlevel >= $startlevel) {
 105                 $index.=&$indent."</li>\n" if $curlevel;
 106                 $curlevel--;
 107                 $index.=&$indent."</ol>\n";
 108         }
 109
 110         $page=~s/(<div class=\"toc\">)/$1\n$index/;
 111         return $page;
 112 }
 113
 114 1