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 2.00;
   8 use HTML::Parser;
   9
  10 sub import { #{{{
  11         hook(type => "preprocess", id => "toc", call => \&preprocess);
  12         hook(type => "format", id => "toc", call => \&format);
  13 } # }}}
  14
  15 my %tocpages;
  16
  17 sub preprocess (@) { #{{{
  18         my %params=@_;
  19
  20         if ($params{page} eq $params{destpage}) {
  21                 $params{levels}=1 unless exists $params{levels};
  22
  23                 # It's too early to generate the toc here, so just record the
  24                 # info.
  25                 $tocpages{$params{destpage}}=\%params;
  26
  27                 return "\n<div class=\"toc\"></div>\n";
  28         }
  29         else {
  30                 # Don't generate toc in an inlined page, doesn't work
  31                 # right.
  32                 return "";
  33         }
  34 } # }}}
  35
  36 sub format (@) { #{{{
  37         my %params=@_;
  38         my $content=$params{content};
  39
  40         return $content unless exists $tocpages{$params{page}};
  41         %params=%{$tocpages{$params{page}}};
  42
  43         my $p=HTML::Parser->new(api_version => 3);
  44         my $page="";
  45         my $index="";
  46         my %anchors;
  47         my $curlevel;
  48         my $startlevel=0;
  49         my $liststarted=0;
  50         my $indent=sub { "\t" x $curlevel };
  51         $p->handler(start => sub {
  52                 my $tagname=shift;
  53                 my $text=shift;
  54                 if ($tagname =~ /^h(\d+)$/i) {
  55                         my $level=$1;
  56                         my $anchor="index".++$anchors{$level}."h$level";
  57                         $page.="$text<a name=\"$anchor\"></a>";
  58
  59                         # Take the first header level seen as the topmost level,
  60                         # even if there are higher levels seen later on.
  61                         if (! $startlevel) {
  62                                 $startlevel=$level;
  63                                 $curlevel=$startlevel-1;
  64                         }
  65                         elsif ($level < $startlevel) {
  66                                 $level=$startlevel;
  67                         }
  68
  69                         return if $level - $startlevel >= $params{levels};
  70
  71                         if ($level > $curlevel) {
  72                                 while ($level > $curlevel + 1) {
  73                                         $index.=&$indent."<ol>\n";
  74                                         $curlevel++;
  75                                         $index.=&$indent."<li class=\"L$curlevel\">\n";
  76                                 }
  77                                 $index.=&$indent."<ol>\n";
  78                                 $curlevel=$level;
  79                                 $liststarted=1;
  80                         }
  81                         elsif ($level < $curlevel) {
  82                                 while ($level < $curlevel) {
  83                                         $index.=&$indent."</li>\n" if $curlevel;
  84                                         $curlevel--;
  85                                         $index.=&$indent."</ol>\n";
  86                                 }
  87                                 $liststarted=0;
  88                         }
  89
  90                         $index.=&$indent."</li>\n" unless $liststarted;
  91                         $liststarted=0;
  92                         $index.=&$indent."<li class=\"L$curlevel\">".
  93                                 "<a href=\"#$anchor\">";
  94
  95                         $p->handler(text => sub {
  96                                 $page.=join("", @_);
  97                                 $index.=join("", @_);
  98                         }, "dtext");
  99                         $p->handler(end => sub {
 100                                 my $tagname=shift;
 101                                 if ($tagname =~ /^h(\d+)$/i) {
 102                                         $p->handler(text => undef);
 103                                         $p->handler(end => undef);
 104                                         $index.="</a>\n";
 105                                 }
 106                                 $page.=join("", @_);
 107                         }, "tagname, text");
 108                 }
 109                 else {
 110                         $page.=$text;
 111                 }
 112         }, "tagname, text");
 113         $p->handler(default => sub { $page.=join("", @_) }, "text");
 114         $p->parse($content);
 115         $p->eof;
 116
 117         while ($startlevel && $curlevel >= $startlevel) {
 118                 $index.=&$indent."</li>\n" if $curlevel;
 119                 $curlevel--;
 120                 $index.=&$indent."</ol>\n";
 121         }
 122
 123         $page=~s/(<div class=\"toc\">)/$1\n$index/;
 124         return $page;
 125 }
 126
 127 1