create translated underlays in mdwn format

These are for use by wikis where the primary language is not English.
On such a wiki, it makes sense to use an underlay has the source for pages
in the native language.

IkiWiki/Plugin/po.pm

@@ -904,10 +904,10 @@ sub otherlanguagesloop ($) {
 		}
 	}
 	return sort {
-			return -1 if $a->{code} eq $config{po_master_language}{code};
-			return 1 if $b->{code} eq $config{po_master_language}{code};
-			return $a->{language} cmp $b->{language};
-		} @ret;
+		return -1 if $a->{code} eq $config{po_master_language}{code};
+		return 1 if $b->{code} eq $config{po_master_language}{code};
+		return $a->{language} cmp $b->{language};
+	} @ret;
 }
 
 sub homepageurl (;$) {

Makefile.PL

@@ -64,6 +64,7 @@ underlaypo: ikiwiki.out
 	done
 	install -d po/underlays/empty
 	$(PERL) -Iblib/lib $(extramodules) $(tflag) ikiwiki.out -libdir . -setup underlaypo.setup -refresh
+	PERL5LIB=. po/po2wiki underlaypo.setup
 	find po/underlays -name \*.mdwn | xargs rm -f
 
 extra_clean:

doc/plugins/po.mdwn

@@ -286,6 +286,9 @@ The when the user edits index, they get a nice mdwn file to start from.
 
 So, we seem to have two cases, in one po files from the underlay should be
 used, in the other not. Hmm. Support both?
+
+> Update -- I've written po2wiki, which can spit out translated underlays
+> in markdown format. 
 --[[Joey]] 
 
 Duplicate %links ?

po/po2wiki

@@ -0,0 +1,37 @@
+#!/usr/bin/perl
+# This program uses the po plugin's internals to convert the po files that
+# it generates back into translated wiki source files that can be used as a
+# underlay for a non-English wiki.
+use warnings;
+use strict;
+use IkiWiki;
+
+# Load the passed setup file and initialize ikiwiki config.
+%config=IkiWiki::defaultconfig();
+require IkiWiki::Setup;
+IkiWiki::Setup::load(shift);
+IkiWiki::loadplugins();
+IkiWiki::checkconfig();
+
+require IkiWiki::Render;
+IkiWiki::srcdir_check();
+my ($files, $pages)=IkiWiki::find_src_files();
+
+foreach my $file (@$files) {
+	my $page=pagename($file);
+	$pagesources{$page}=$file; # used by po plugin functions
+}
+
+foreach my $ll (keys %{$config{po_slave_languages}}) {
+	$config{destdir}="po/out.$ll";
+
+	foreach my $file (@$files) {
+		my $page=pagename($file);
+		my ($masterpage, $lang) = IkiWiki::Plugin::po::_istranslation($page);
+		next unless defined $lang && $lang eq $ll;
+		
+		my $content=readfile(srcfile($file));
+		$content=IkiWiki::Plugin::po::po_to_markup($page, $content);
+		writefile($masterpage.".".$config{default_pageext}, $config{destdir}, $content);
+	}
+}