# Make Index - HTMLファイルのhタグから目次を生成する
# Copyright (C) Takashi Utsunomiya. All Rights Reserved.
# http://uttsu.com/
# 2002.08.07-

# Usage: perl mkindex.pl file

# 2003.03.20	ver 1.02
#	- <a name=?></a> から <h? id=?>に変更
# ver 1.01	2002.10.19
# ver 1.00	2002.08.07

# ■init
use strict;

my $file = $ARGV[0];

main();
exit;

# ■main
sub main {
	open(IN, $file) or die;
	my @in = <IN>;
	close(IN);

	my (@body, @head, @index, $index, $anchor, $while_old_index);
	foreach (@in) {
		if ($while_old_index) {
			$while_old_index = 0 if (/^$/);
			next;
		}
		if (/^<h2>目次<\/h2>/) {
			$while_old_index = 1;
			next;
		}

		if (/^<h([2345])( id=.*?)?>(.*)(<\/h\d>)/i) {
			if ($index < $1) {
				push(@head, "\t" x ($1-2) . "<ul>\n");
				$index[$1] = 0;
			} elsif ($index > $1) {
				push(@head, "\t" x ($index-2) . "</ul>\n");
			}
			$index = $1;
			$index[$1-2]++;

			$anchor = '';
			for (my $i=0; $i<$1-1; $i++) {
				$anchor .= ($i == 0 ? '' : '_') . $index[$i];
			}

			push(@head, "\t" x ($index-2) . "<li><a href=#$anchor>$3</a>\n");
			push(@body, "<h$1 id=$anchor>$3$4\n");
		} else {
			push(@body, $_);
		}
	}
	unshift(@head, "<h2>目次</h2>\n");
	push(@head, "\t" x ($index-2) . "</ul>\n") if ($index > 2);
	push(@head, "</ul>\n\n");

	open(OUT, "> $file\.bak") or die;
	print OUT @in;
	close(OUT);

	open(OUT, "> $file") or die;
	my $head = 1;
	foreach (@body) {
		if ($head && /^<h[2345]/) {
			$head = 0;
			print OUT @head;
		}
		print OUT;
	}
	close(OUT);
}