#!/usr/bin/perl

use Pod::Tree;
	
sub escape_texi($) {
   local $_ = shift;
   s/([\@\{\}])/\@$1/g;
   s/\n+/ /g;
   $_;
}

sub example {
   my $text = $_[0];
   print "\n\n\@example\n";
   $text =~ s/\n+$//;
   $text =~ s/([\@\{\}])/\@$1/g;
   print $text;
   print "\n\@end example\n\n";
}

while (<>) {
   if (/^\@c INCLUDE-(\S+) (\S+)/) {
      my $type = $1;
      my $name = $2;
      my $path = $2;

      $name =~ s/\.(\d)$/($1)/;

      print "\@chapter $name\n\n";

      if ($type eq "POD") {
         open my $x, "<$path.pod" or die "$path.pod: $!";
         my $data = do { local $/; <$x> };

         my $pod = new Pod::Tree;
         $pod->load_string($data);
      
         my $walker; $walker = sub {
            my $n = $_[0];
            if ($n->is_code) {
               # nop
            } elsif ($n->is_link) {
               my $target = $n->get_target;
               my $page    = $target->get_page;
               my $section = $target->get_section;
               
               #print "<b>";
               $walker->($_) for @{$n->get_children};
               #print "</b>";
            } elsif ($n->is_text) {
               print escape_texi $n->get_text;
            } elsif ($n->is_verbatim) {
               example $n->get_text;
            } elsif ($n->is_sequence) {
               if ($n->get_letter eq "C") {
                  print "\@t{";
                  $walker->($_) for @{$n->get_children};
                  print "}";
               } elsif ($n->get_letter eq "B") {
                  print "\@strong{";
                  $walker->($_) for @{$n->get_children};
                  print "}";
               } elsif ($n->get_letter eq "I" or $n->get_letter eq "F") {
                  print "\@emph{";
                  $walker->($_) for @{$n->get_children};
                  print "}";
               } else {
                  # S would mean to use nbsp
                  $walker->($_) for @{$n->get_children};
               }
            } elsif ($n->is_command) {
               if ($n->is_c_head1) {
                  print "\n\@section ";
                  $walker->($_) for @{$n->get_children};
                  print "\n";
               } elsif ($n->is_c_head2) {
                  print "\n\n\@subsection ";
                  $walker->($_) for @{$n->get_children};
                  print "\n";
               } else {
                  # nop?
               }
            } elsif ($n->is_ordinary) {
               $walker->($_) for @{$n->get_children};
               print "\@refill\n";
            } elsif ($n->is_root) {
               $walker->($_) for @{$n->get_children};
            } elsif ($n->is_list) {
               print "\n\n\@itemize\n";
               $walker->($_) for @{$n->get_children};
               print "\@end itemize\n\n";
            } elsif ($n->is_item) {
               print "\n\n\@item\n";
                  print "\@b{";
                  $walker->($_) for @{$n->get_children};
                  print "}\n\n";
               $walker->($_) for @{$n->get_siblings};
            } else {
               die "UNKNOWN NODE $_[0]{type}<br/>";
               $walker->($_) for @{$n->get_children};
            }
         };
      
         $walker->($pod->get_root);
      } elsif ($type eq "TEXT") {
         open my $x, "<$path" or die "$path: $!";
         my $data = do { local $/; <$x> };

         print $data;
      } elsif ($type eq "EXAMPLE") {
         open my $x, "<$path" or die "$path: $!";
         my $data = do { local $/; <$x> };

         example $data;
      }
   } else {
      print;
   }
}