#!/usr/bin/perl
use warnings;
use strict;
use IkiWiki;
use HTML::Entities;

my $regex = qr{
	(\\?)		# 1: escape?
	\[\[(!?)	# directive open; 2: optional prefix
	([-\w]+)	# 3: command
	(		# 4: the parameters (including initial whitespace)
	\s+
		(?:
			(?:[-\w]+=)?		# named parameter key?
			(?:
				""".*?"""	# triple-quoted value
				|
				"[^"]+"		# single-quoted value
				|
				[^\s\]]+	# unquoted value
			)
			\s*			# whitespace or end
						# of directive
		)
	*)		# 0 or more parameters
	\]\]		# directive closed
}sx;

sub handle_directive {
	my $escape = shift;
	my $prefix = shift;
	my $directive = shift;
	my $args = shift;

	if (length $escape) {
		return "${escape}[[${prefix}${directive}${args}]]"
	}
	if ($directive =~ m/^(if|more|table|template|toggleable)$/) {
		$args =~ s{$regex}{handle_directive($1, $2, $3, $4)}eg;
	}
	return "[[!${directive}${args}]]"
}

sub prefix_directives {
	loadsetup(shift);

	IkiWiki::loadplugins();
	IkiWiki::checkconfig();
	IkiWiki::loadindex();

	if (! %pagesources) {
		error "ikiwiki has not built this wiki yet, cannot transition";
	}

	foreach my $page (values %pagesources) {
		next unless defined pagetype($page) &&
		            -f $config{srcdir}."/".$page;
		my $content=readfile($config{srcdir}."/".$page);
		my $oldcontent=$content;
		$content=~s{$regex}{handle_directive($1, $2, $3, $4)}eg;
		if ($oldcontent ne $content) {
			writefile($page, $config{srcdir}, $content);
		}
	}
}

sub indexdb {
	setstatedir(shift);

	# Note: No lockwiki here because ikiwiki already locks it
	# before calling this.	
	if (! IkiWiki::oldloadindex()) {
		die "failed to load index\n";
	}
	if (! IkiWiki::saveindex()) {
		die "failed to save indexdb\n"
	}
	if (! IkiWiki::loadindex()) {
		die "transition failed, cannot load new indexdb\n";
	}
	if (! unlink("$config{wikistatedir}/index")) {
		die "unlink failed: $!\n";
	}
}

sub hashpassword {
	setstatedir(shift);

	eval q{use IkiWiki::UserInfo};
	eval q{use Authen::Passphrase::BlowfishCrypt};
	if ($@) {
		error("ikiwiki-transition hashpassword: failed to load Authen::Passphrase, passwords not hashed");
	}

	IkiWiki::lockwiki();
	IkiWiki::loadplugin("passwordauth");
	my $userinfo = IkiWiki::userinfo_retrieve();
	foreach my $user (keys %{$userinfo}) {
		if (ref $userinfo->{$user} &&
		    exists $userinfo->{$user}->{password} &&
		    length $userinfo->{$user}->{password} &&
		    ! exists $userinfo->{$user}->{cryptpassword}) {
			IkiWiki::Plugin::passwordauth::setpassword($user, $userinfo->{$user}->{password});
		}
	}
}

sub aggregateinternal {
	loadsetup(shift);
	require IkiWiki::Plugin::aggregate;
	IkiWiki::checkconfig();
	IkiWiki::Plugin::aggregate::migrate_to_internal();
}

sub setupformat {
	my $setup=shift;

	loadsetup($setup);
	IkiWiki::checkconfig();
	
	# unpack old-format wrappers setting into new fields
	my $cgi_seen=0;
	my $rcs_seen=0;
	foreach my $wrapper (@{$config{wrappers}}) {
		if ($wrapper->{cgi}) {
			if ($cgi_seen) {
				die "don't know what to do with second cgi wrapper ".$wrapper->{wrapper}."\n";
			}
			$cgi_seen++;
			print "setting cgi_wrapper to ".$wrapper->{wrapper}."\n";
			$config{cgi_wrapper}=$wrapper->{wrapper};
			$config{cgi_wrappermode}=$wrapper->{wrappermode}
				if exists $wrapper->{wrappermode};
		}
		elsif ($config{rcs}) {
			if ($rcs_seen) {
				die "don't know what to do with second rcs wrapper ".$wrapper->{wrapper}."\n";
			}
			$rcs_seen++;
			print "setting $config{rcs}_wrapper to ".$wrapper->{wrapper}."\n";
			$config{$config{rcs}."_wrapper"}=$wrapper->{wrapper};
			$config{$config{rcs}."_wrappermode"}=$wrapper->{wrappermode}
				if exists $wrapper->{wrappermode};
		}
		else {
			die "don't know what to do with wrapper ".$wrapper->{wrapper}."\n";
		}
	}

	IkiWiki::Setup::dump($setup);
}

sub moveprefs {
	my $setup=shift;

	loadsetup($setup);
	IkiWiki::checkconfig();

	eval q{use IkiWiki::UserInfo};
	error $@ if $@;

	foreach my $field (qw{allowed_attachments locked_pages}) {
		my $orig=$config{$field};
		foreach my $admin (@{$config{adminuser}}) {
			my $a=IkiWiki::userinfo_get($admin, $field);
			if (defined $a && length $a &&
			    # might already have been moved
			    (! defined $orig || $a ne $orig)) {
			    	if (defined $config{$field} &&
				    length $config{$field}) {
					$config{$field}=IkiWiki::pagespec_merge($config{$field}, $a);
				}
				else {
					$config{$field}=$a;
				}
			}
		}
	}

	my %banned=map { $_ => 1 } @{$config{banned_users}}, IkiWiki::get_banned_users();
	$config{banned_users}=[sort keys %banned];

	IkiWiki::Setup::dump($setup);
}

sub deduplinks {
	loadsetup(shift);
	IkiWiki::loadplugins();
	IkiWiki::checkconfig();
	IkiWiki::loadindex();
	foreach my $page (keys %links) {
		my %l;
		$l{$_}=1 foreach @{$links{$page}};
		$links{$page}=[keys %l]
	}
	IkiWiki::saveindex();
}

sub setstatedir {
	my $dirorsetup=shift;

	if (! defined $dirorsetup) {
		usage();		
	}

	if (-d $dirorsetup) {
		$config{wikistatedir}=$dirorsetup."/.ikiwiki";
	}
	elsif (-f $dirorsetup) {
		loadsetup($dirorsetup);
	}
	else {
		error("ikiwiki-transition: $dirorsetup does not exist");
	}

	if (! -d $config{wikistatedir}) {
		error("ikiwiki-transition: $config{wikistatedir} does not exist");
	}
}
	
sub loadsetup {
	my $setup=shift;
	if (! defined $setup) {
		usage();
	}

	require IkiWiki::Setup;

	%config = IkiWiki::defaultconfig();
	IkiWiki::Setup::load($setup);
}

sub usage {
	print STDERR "Usage: ikiwiki-transition type ...\n";
	print STDERR "Currently supported transition subcommands:\n";
	print STDERR "\tprefix_directives setupfile ...\n";
	print STDERR "\taggregateinternal setupfile\n";
	print STDERR "\tsetupformat setupfile\n";
	print STDERR "\tmoveprefs setupfile\n";
	print STDERR "\thashpassword setupfile|srcdir\n";
	print STDERR "\tindexdb setupfile|srcdir\n";
	print STDERR "\tdeduplinks setupfile\n";
	exit 1;
}

usage() unless @ARGV;

my $mode=shift;
if ($mode eq 'prefix_directives') {
	prefix_directives(@ARGV);
}
elsif ($mode eq 'hashpassword') {
	hashpassword(@ARGV);
}
elsif ($mode eq 'indexdb') {
	indexdb(@ARGV);
}
elsif ($mode eq 'aggregateinternal') {
	aggregateinternal(@ARGV);
}
elsif ($mode eq 'setupformat') {
	setupformat(@ARGV);
}
elsif ($mode eq 'moveprefs') {
	moveprefs(@ARGV);
}
elsif ($mode eq 'deduplinks') {
	deduplinks(@ARGV);
}
else {
	usage();
}

package IkiWiki;

# A slightly modified version of the old loadindex function.
sub oldloadindex {
	%oldrenderedfiles=%pagectime=();
	if (! $config{rebuild}) {
		%pagesources=%pagemtime=%oldlinks=%links=%depends=
			%destsources=%renderedfiles=%pagecase=%pagestate=();
	}
	open (my $in, "<", "$config{wikistatedir}/index") || return;
	while (<$in>) {
		chomp;
		my %items;
		$items{link}=[];
		$items{dest}=[];
		foreach my $i (split(/ /, $_)) {
			my ($item, $val)=split(/=/, $i, 2);
			push @{$items{$item}}, decode_entities($val);
		}

		next unless exists $items{src}; # skip bad lines for now

		my $page=pagename($items{src}[0]);
		if (! $config{rebuild}) {
			$pagesources{$page}=$items{src}[0];
			$pagemtime{$page}=$items{mtime}[0];
			$oldlinks{$page}=[@{$items{link}}];
			$links{$page}=[@{$items{link}}];
			$depends{$page}={ $items{depends}[0] => $IkiWiki::DEPEND_CONTENT } if exists $items{depends};
			$destsources{$_}=$page foreach @{$items{dest}};
			$renderedfiles{$page}=[@{$items{dest}}];
			$pagecase{lc $page}=$page;
			foreach my $k (grep /_/, keys %items) {
				my ($id, $key)=split(/_/, $k, 2);
				$pagestate{$page}{decode_entities($id)}{decode_entities($key)}=$items{$k}[0];
			}
		}
		$oldrenderedfiles{$page}=[@{$items{dest}}];
		$pagectime{$page}=$items{ctime}[0];
	}

	# saveindex relies on %hooks being populated, else it won't save
	# the page state owned by a given hook. But no plugins are loaded
	# by this program, so populate %hooks with all hook ids that
	# currently have page state.
	foreach my $page (keys %pagemtime) {
		foreach my $id (keys %{$pagestate{$page}}) {
			$hooks{_dummy}{$id}=1;
		}
	}
	
	return close($in);
}

# Used to be in IkiWiki/UserInfo, but only used here now.
sub get_banned_users () {
	my @ret;
	my $userinfo=userinfo_retrieve();
	foreach my $user (keys %{$userinfo}) {
		push @ret, $user if $userinfo->{$user}->{banned};
	}
	return @ret;
}

# Used to be in IkiWiki, but only used here (to migrate admin prefs into the
# setup file) now.
sub pagespec_merge ($$) {
	my $a=shift;
	my $b=shift;

	return $a if $a eq $b;
	return "($a) or ($b)";
}

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