#!/usr/bin/perl
package IkiWiki::Plugin::autoindex;

use warnings;
use strict;
use IkiWiki 3.00;
use Encode;

sub import {
	hook(type => "getsetup", id => "autoindex", call => \&getsetup);
	hook(type => "refresh", id => "autoindex", call => \&refresh);
}

sub getsetup () {
	return
		plugin => {
			safe => 1,
			rebuild => 0,
		},
}

sub genindex ($) {
	my $page=shift;
	my $file=newpagefile($page, $config{default_pageext});
	my $template=template("autoindex.tmpl");
	$template->param(page => $page);
	writefile($file, $config{srcdir}, $template->output);
	if ($config{rcs}) {
		IkiWiki::rcs_add($file);
	}
}

sub refresh () {
	eval q{use File::Find};
	error($@) if $@;

	my (%pages, %dirs);
	foreach my $dir ($config{srcdir}, @{$config{underlaydirs}}, $config{underlaydir}) {
		find({
			no_chdir => 1,
			wanted => sub {
				$_=decode_utf8($_);
				if (IkiWiki::file_pruned($_, $dir)) {
					$File::Find::prune=1;
				}
				elsif (! -l $_) {
					my ($f)=/$config{wiki_file_regexp}/; # untaint
					return unless defined $f;
					$f=~s/^\Q$dir\E\/?//;
					return unless length $f;
					return if $f =~ /\._([^.]+)$/; # skip internal page
					if (! -d _) {
						$pages{pagename($f)}=1;
					}
					elsif ($dir eq $config{srcdir}) {
						$dirs{$f}=1;
					}
				}
			}
		}, $dir);
	}
	
	my %deleted;
        if (ref $pagestate{index}{autoindex}{deleted}) {
	       %deleted=%{$pagestate{index}{autoindex}{deleted}};
		foreach my $dir (keys %deleted) {
			# remove deleted page state if the deleted page is re-added,
			# or if all its subpages are deleted
			if ($deleted{$dir} && (exists $pages{$dir} ||
			                       ! grep /^$dir\/.*/, keys %pages)) {
				delete $deleted{$dir};
			}
		}
		$pagestate{index}{autoindex}{deleted}=\%deleted;
	}

	my @needed;
	foreach my $dir (keys %dirs) {
		if (! exists $pages{$dir} && ! $deleted{$dir} &&
		    grep /^$dir\/.*/, keys %pages) {
		    	if (exists $IkiWiki::pagemtime{$dir}) {
				# This page must have just been deleted, so
				# don't re-add it. And remember it was
				# deleted.
				if (! ref $pagestate{index}{autoindex}{deleted}) {
					$pagestate{index}{autoindex}{deleted}={};
				}
				${$pagestate{index}{autoindex}{deleted}}{$dir}=1;
			}
			else {
				push @needed, $dir;
			}
		}
	}
	
	if (@needed) {
		if ($config{rcs}) {
			IkiWiki::disable_commit_hook();
		}
		foreach my $page (@needed) {
			genindex($page);
		}
		if ($config{rcs}) {
			IkiWiki::rcs_commit_staged(
				gettext("automatic index generation"),
				undef, undef);
			IkiWiki::enable_commit_hook();
		}
	}
}

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