#use wml::std::case global=lower

# Usage: 
# 	0. Edit the "index file" with file list.
# 	1. include this file with "current page" and "index file"
#	   #include "guide.wh" page="about.html" index="Index"
#	2. use <guide> tag to display.
<define-tag guide whitespace=delete>
<: {
	my $page = '$(page)';
	my $index = '$(index)';
	my $prev, $next, $target;
	my @filelist;
	$prev = $next = "";
	$target = 0;

	# File Read
	open(INDEX, $index);
	foreach (<INDEX>) {
		chop;
		next if /^#/;
		next if /^$/;
		push @filelist, $_;
	}
	close(INDEX);

	# Target File Search
	foreach (@filelist) {
		last if ($_ eq $page);
		$target++;
	}


	# File Setting
	$prev = $filelist[$target-1] if $target > 0;
	$next = $filelist[$target+1];
	$prev = "" if $prev eq $filelist[0];

	# Guide Printout
	if ($prev ne "") {
		print qq!<a href="$prev">PREV</a>!;
	} else { print qq!PREV!; }
	print ' &lt;&lt; ';
	print "<a href=$filelist[0]>TOP</a>";
	print ' &gt;&gt; ';
	if ($next ne "") {
		print qq!<a href="$next">NEXT</a>!;
	} else { print qq!NEXT!; }
} :>
</define-tag>