X-Git-Url: http://git.vanrenterghem.biz/git.ikiwiki.info.git/blobdiff_plain/a0deb3038c45c066e2c0c3acb8c6c4a93ca3301d..3ee571390e3697a3b738ea6791ac7f07052a709c:/IkiWiki/Plugin/po.pm

diff --git a/IkiWiki/Plugin/po.pm b/IkiWiki/Plugin/po.pm
index 07896d95a..759e812e6 100644
--- a/IkiWiki/Plugin/po.pm
+++ b/IkiWiki/Plugin/po.pm
@@ -1,22 +1,34 @@
 #!/usr/bin/perl
 # .po as a wiki page type
+# Licensed under GPL v2 or greater
+# Copyright (C) 2008-2009 intrigeri <intrigeri@boum.org>
 # inspired by the GPL'd po4a-translate,
 # which is Copyright 2002, 2003, 2004 by Martin Quinson (mquinson#debian.org)
 package IkiWiki::Plugin::po;
 
 use warnings;
 use strict;
-use IkiWiki 2.00;
+use IkiWiki 3.00;
 use Encode;
+eval q{use Locale::Po4a::Common qw(nowrapi18n !/.*/)};
+if ($@) {
+	print STDERR gettext("warning: Old po4a detected! Recommend upgrade to 0.35.")."\n";
+	eval q{use Locale::Po4a::Common qw(!/.*/)};
+	die $@ if $@;
+}
 use Locale::Po4a::Chooser;
+use Locale::Po4a::Po;
 use File::Basename;
 use File::Copy;
 use File::Spec;
 use File::Temp;
 use Memoize;
+use UNIVERSAL;
 
 my %translations;
-our %filtered;
+my @origneedsbuild;
+my %origsubs;
+
 memoize("istranslatable");
 memoize("_istranslation");
 memoize("percenttranslated");
@@ -25,19 +37,56 @@ sub import {
 	hook(type => "getsetup", id => "po", call => \&getsetup);
 	hook(type => "checkconfig", id => "po", call => \&checkconfig);
 	hook(type => "needsbuild", id => "po", call => \&needsbuild);
-	hook(type => "targetpage", id => "po", call => \&targetpage);
-	hook(type => "tweakurlpath", id => "po", call => \&tweakurlpath);
-	hook(type => "tweakbestlink", id => "po", call => \&tweakbestlink);
+	hook(type => "scan", id => "po", call => \&scan, last => 1);
 	hook(type => "filter", id => "po", call => \&filter);
 	hook(type => "htmlize", id => "po", call => \&htmlize);
-	hook(type => "pagetemplate", id => "po", call => \&pagetemplate);
+	hook(type => "pagetemplate", id => "po", call => \&pagetemplate, last => 1);
+	hook(type => "rename", id => "po", call => \&renamepages, first => 1);
+	hook(type => "delete", id => "po", call => \&mydelete);
+	hook(type => "change", id => "po", call => \&change);
+	hook(type => "checkcontent", id => "po", call => \&checkcontent);
+	hook(type => "canremove", id => "po", call => \&canremove);
+	hook(type => "canrename", id => "po", call => \&canrename);
+	hook(type => "editcontent", id => "po", call => \&editcontent);
+	hook(type => "formbuilder_setup", id => "po", call => \&formbuilder_setup, last => 1);
+	hook(type => "formbuilder", id => "po", call => \&formbuilder);
+
+	$origsubs{'bestlink'}=\&IkiWiki::bestlink;
+	inject(name => "IkiWiki::bestlink", call => \&mybestlink);
+	$origsubs{'beautify_urlpath'}=\&IkiWiki::beautify_urlpath;
+	inject(name => "IkiWiki::beautify_urlpath", call => \&mybeautify_urlpath);
+	$origsubs{'targetpage'}=\&IkiWiki::targetpage;
+	inject(name => "IkiWiki::targetpage", call => \&mytargetpage);
+	$origsubs{'urlto'}=\&IkiWiki::urlto;
+	inject(name => "IkiWiki::urlto", call => \&myurlto);
+	$origsubs{'cgiurl'}=\&IkiWiki::cgiurl;
+	inject(name => "IkiWiki::cgiurl", call => \&mycgiurl);
+	$origsubs{'rootpage'}=\&IkiWiki::rootpage;
+	inject(name => "IkiWiki::rootpage", call => \&myrootpage);
 }
 
-sub getsetup () { #{{{
+
+# ,----
+# | Table of contents
+# `----
+
+# 1. Hooks
+# 2. Injected functions
+# 3. Blackboxes for private data
+# 4. Helper functions
+# 5. PageSpecs
+
+
+# ,----
+# | Hooks
+# `----
+
+sub getsetup () {
 	return
 		plugin => {
 			safe => 0,
 			rebuild => 1, # format plugin
+			section => "format",
 		},
 		po_master_language => {
 			type => "string",
@@ -53,7 +102,7 @@ sub getsetup () { #{{{
 			type => "string",
 			example => {
 				'fr' => 'Français',
-				'es' => 'Castellano',
+				'es' => 'Español',
 				'de' => 'Deutsch'
 			},
 			description => "slave languages (PO files)",
@@ -62,7 +111,7 @@ sub getsetup () { #{{{
 		},
 		po_translatable_pages => {
 			type => "pagespec",
-			example => "!*/Discussion",
+			example => "* and !*/Discussion",
 			description => "PageSpec controlling which pages are translatable",
 			link => "ikiwiki/PageSpec",
 			safe => 1,
@@ -75,427 +124,1090 @@ sub getsetup () { #{{{
 			safe => 1,
 			rebuild => 1,
 		},
-} #}}}
+}
 
-sub checkconfig () { #{{{
-	foreach my $field (qw{po_master_language po_slave_languages}) {
+sub checkconfig () {
+	foreach my $field (qw{po_master_language}) {
 		if (! exists $config{$field} || ! defined $config{$field}) {
-			error(sprintf(gettext("Must specify %s"), $field));
+			error(sprintf(gettext("Must specify %s when using the %s plugin"),
+				      $field, 'po'));
 		}
 	}
+	delete $config{po_slave_languages}{$config{po_master_language}{code}};;
+
+	map {
+		islanguagecode($_)
+			or error(sprintf(gettext("%s is not a valid language code"), $_));
+	} ($config{po_master_language}{code}, keys %{$config{po_slave_languages}});
+
+	if (! exists $config{po_translatable_pages} ||
+	    ! defined $config{po_translatable_pages}) {
+		$config{po_translatable_pages}="";
+	}
 	if (! exists $config{po_link_to} ||
 	    ! defined $config{po_link_to}) {
-	    $config{po_link_to}="default";
+		$config{po_link_to}='default';
 	}
-	if (! exists $config{po_translatable_pages} ||
-	    ! defined $config{po_translatable_pages}) {
-	    $config{po_translatable_pages}="";
+	elsif ($config{po_link_to} !~ /^(default|current|negotiated)$/) {
+		warn(sprintf(gettext('%s is not a valid value for po_link_to, falling back to po_link_to=default'),
+			     $config{po_link_to}));
+		$config{po_link_to}='default';
 	}
-	if ($config{po_link_to} eq "negotiated" && ! $config{usedirs}) {
-		error(gettext("po_link_to=negotiated requires usedirs to be set"));
+	elsif ($config{po_link_to} eq "negotiated" && ! $config{usedirs}) {
+		warn(gettext('po_link_to=negotiated requires usedirs to be enabled, falling back to po_link_to=default'));
+		$config{po_link_to}='default';
 	}
+
 	push @{$config{wiki_file_prune_regexps}}, qr/\.pot$/;
-} #}}}
 
-sub potfile ($) { #{{{
-	my $masterfile=shift;
-	(my $name, my $dir, my $suffix) = fileparse($masterfile, qr/\.[^.]*/);
-	return File::Spec->catfile($dir, $name . ".pot");
-} #}}}
+	# Translated versions of the underlays are added if available.
+	foreach my $underlay ("basewiki",
+	                      map { m/^\Q$config{underlaydirbase}\E\/*(.*)/ }
+	                          reverse @{$config{underlaydirs}}) {
+		next if $underlay=~/^locale\//;
 
-sub pofile ($$) { #{{{
-	my $masterfile=shift;
-	my $lang=shift;
-	(my $name, my $dir, my $suffix) = fileparse($masterfile, qr/\.[^.]*/);
-	return File::Spec->catfile($dir, $name . "." . $lang . ".po");
-} #}}}
+		# Underlays containing the po files for slave languages.
+		foreach my $ll (keys %{$config{po_slave_languages}}) {
+			add_underlay("po/$ll/$underlay")
+				if -d "$config{underlaydirbase}/po/$ll/$underlay";
+		}
+	
+		if ($config{po_master_language}{code} ne 'en') {
+			# Add underlay containing translated source files
+			# for the master language.
+			add_underlay("locale/$config{po_master_language}{code}/$underlay")
+				if -d "$config{underlaydirbase}/locale/$config{po_master_language}{code}/$underlay";
+		}
+	}
+}
 
-sub refreshpot ($) { #{{{
-	my $masterfile=shift;
-	my $potfile=potfile($masterfile);
-	my %options = ("markdown" => (pagetype($masterfile) eq 'mdwn') ? 1 : 0);
-	my $doc=Locale::Po4a::Chooser::new('text',%options);
-	$doc->read($masterfile);
-	$doc->{TT}{utf_mode} = 1;
-	$doc->{TT}{file_in_charset} = 'utf-8';
-	$doc->{TT}{file_out_charset} = 'utf-8';
-	$doc->parse;
-	$doc->writepo($potfile);
-} #}}}
+sub needsbuild () {
+	my $needsbuild=shift;
 
-sub refreshpofiles ($@) { #{{{
-	my $masterfile=shift;
-	my @pofiles=@_;
+	# backup @needsbuild content so that change() can know whether
+	# a given master page was rendered because its source file was changed
+	@origneedsbuild=(@$needsbuild);
 
-	my $potfile=potfile($masterfile);
-	error("[po/refreshpofiles] POT file ($potfile) does not exist") unless (-e $potfile);
+	flushmemoizecache();
+	buildtranslationscache();
 
-	foreach my $pofile (@pofiles) {
-		if (-e $pofile) {
-			my $cmd = "msgmerge -U --backup=none $pofile $potfile";
-			system ($cmd) == 0
-				or error("[po/refreshpofiles:$pofile] failed to update");
+	# make existing translations depend on the corresponding master page
+	foreach my $master (keys %translations) {
+		map add_depends($_, $master), values %{otherlanguages($master)};
+	}
+}
+
+# Massage the recorded state of internal links so that:
+# - it matches the actually generated links, rather than the links as written
+#   in the pages' source
+# - backlinks are consistent in all cases
+sub scan (@) {
+	my %params=@_;
+	my $page=$params{page};
+	my $content=$params{content};
+
+	if (istranslation($page)) {
+		foreach my $destpage (@{$links{$page}}) {
+			if (istranslatable($destpage)) {
+				# replace the occurence of $destpage in $links{$page}
+				for (my $i=0; $i<@{$links{$page}}; $i++) {
+					if (@{$links{$page}}[$i] eq $destpage) {
+						@{$links{$page}}[$i] = $destpage . '.' . lang($page);
+						last;
+					}
+				}
+			}
 		}
-		else {
-			File::Copy::syscopy($potfile,$pofile)
-				or error("[po/refreshpofiles:$pofile] failed to copy the POT file");
+	}
+	elsif (! istranslatable($page) && ! istranslation($page)) {
+		foreach my $destpage (@{$links{$page}}) {
+			if (istranslatable($destpage)) {
+				# make sure any destpage's translations has
+				# $page in its backlinks
+				push @{$links{$page}},
+					values %{otherlanguages($destpage)};
+			}
 		}
 	}
-} #}}}
+}
 
-sub needsbuild () { #{{{
-	my $needsbuild=shift;
+# We use filter to convert PO to the master page's format,
+# since the rest of ikiwiki should not work on PO files.
+sub filter (@) {
+	my %params = @_;
+
+	my $page = $params{page};
+	my $destpage = $params{destpage};
+	my $content = $params{content};
+	if (istranslation($page) && ! alreadyfiltered($page, $destpage)) {
+		$content = po_to_markup($page, $content);
+		setalreadyfiltered($page, $destpage);
+	}
+	return $content;
+}
+
+sub htmlize (@) {
+	my %params=@_;
+
+	my $page = $params{page};
+	my $content = $params{content};
+
+	# ignore PO files this plugin did not create
+	return $content unless istranslation($page);
+
+	# force content to be htmlize'd as if it was the same type as the master page
+	return IkiWiki::htmlize($page, $page,
+		pagetype(srcfile($pagesources{masterpage($page)})),
+		$content);
+}
+
+sub pagetemplate (@) {
+	my %params=@_;
+	my $page=$params{page};
+	my $destpage=$params{destpage};
+	my $template=$params{template};
+
+	my ($masterpage, $lang) = istranslation($page);
+
+	if (istranslation($page) && $template->query(name => "percenttranslated")) {
+		$template->param(percenttranslated => percenttranslated($page));
+	}
+	if ($template->query(name => "istranslation")) {
+		$template->param(istranslation => scalar istranslation($page));
+	}
+	if ($template->query(name => "istranslatable")) {
+		$template->param(istranslatable => istranslatable($page));
+	}
+	if ($template->query(name => "HOMEPAGEURL")) {
+		$template->param(homepageurl => homepageurl($page));
+	}
+	if ($template->query(name => "otherlanguages")) {
+		$template->param(otherlanguages => [otherlanguagesloop($page)]);
+		map add_depends($page, $_), (values %{otherlanguages($page)});
+	}
+	if ($config{discussion} && istranslation($page)) {
+		if ($page !~ /.*\/\Q$config{discussionpage}\E$/i &&
+		   (length $config{cgiurl} ||
+		    exists $links{$masterpage."/".lc($config{discussionpage})})) {
+			$template->param('discussionlink' => htmllink(
+				$page,
+				$destpage,
+				$masterpage . '/' . $config{discussionpage},
+				noimageinline => 1,
+				forcesubpage => 0,
+				linktext => $config{discussionpage},
+		));
+		}
+	}
+	# Remove broken parentlink to ./index.html on home page's translations.
+	# It works because this hook has the "last" parameter set, to ensure it
+	# runs after parentlinks' own pagetemplate hook.
+	if ($template->param('parentlinks')
+	    && istranslation($page)
+	    && $masterpage eq "index") {
+		$template->param('parentlinks' => []);
+	}
+	if (ishomepage($page) && $template->query(name => "title")) {
+		$template->param(title => $config{wikiname});
+	}
+}
+
+# Add the renamed page translations to the list of to-be-renamed pages.
+sub renamepages (@) {
+	my %params = @_;
+
+	my %torename = %{$params{torename}};
+	my $session = $params{session};
+
+	# Save the page(s) the user asked to rename, so that our
+	# canrename hook can tell the difference between:
+	#  - a translation being renamed as a consequence of its master page
+	#    being renamed
+	#  - a user trying to directly rename a translation
+	# This is why this hook has to be run first, before the list of pages
+	# to rename is modified by other plugins.
+	my @orig_torename;
+	@orig_torename=@{$session->param("po_orig_torename")}
+		if defined $session->param("po_orig_torename");
+	push @orig_torename, $torename{src};
+	$session->param(po_orig_torename => \@orig_torename);
+	IkiWiki::cgi_savesession($session);
 
-	# build %translations, using istranslation's side-effect
-	foreach my $page (keys %pagesources) {
-		istranslation($page);
+	return () unless istranslatable($torename{src});
+
+	my @ret;
+	my %otherpages=%{otherlanguages($torename{src})};
+	while (my ($lang, $otherpage) = each %otherpages) {
+		push @ret, {
+			src => $otherpage,
+			srcfile => $pagesources{$otherpage},
+			dest => otherlanguage($torename{dest}, $lang),
+			destfile => $torename{dest}.".".$lang.".po",
+			required => 0,
+		};
+	}
+	return @ret;
+}
+
+sub mydelete (@) {
+	my @deleted=@_;
+
+	map { deletetranslations($_) } grep istranslatablefile($_), @deleted;
+}
+
+sub change (@) {
+	my @rendered=@_;
+
+	# All meta titles are first extracted at scan time, i.e. before we turn
+	# PO files back into translated markdown; escaping of double-quotes in
+	# PO files breaks the meta plugin's parsing enough to save ugly titles
+	# to %pagestate at this time.
+	#
+	# Then, at render time, every page passes in turn through the Great
+	# Rendering Chain (filter->preprocess->linkify->htmlize), and the meta
+	# plugin's preprocess hook is this time in a position to correctly
+	# extract the titles from slave pages.
+	#
+	# This is, unfortunately, too late: if the page A, linking to the page
+	# B, is rendered before B, it will display the wrongly-extracted meta
+	# title as the link text to B.
+	#
+	# On the one hand, such a corner case only happens on rebuild: on
+	# refresh, every rendered page is fixed to contain correct meta titles.
+	# On the other hand, it can take some time to get every page fixed.
+	# We therefore re-render every rendered page after a rebuild to fix them
+	# at once. As this more or less doubles the time needed to rebuild the
+	# wiki, we do so only when really needed.
+
+	if (@rendered
+	    && exists $config{rebuild} && defined $config{rebuild} && $config{rebuild}
+	    && UNIVERSAL::can("IkiWiki::Plugin::meta", "getsetup")
+	    && exists $config{meta_overrides_page_title}
+	    && defined $config{meta_overrides_page_title}
+	    && $config{meta_overrides_page_title}) {
+		debug(sprintf(gettext("rebuilding all pages to fix meta titles")));
+		resetalreadyfiltered();
+		require IkiWiki::Render;
+		foreach my $file (@rendered) {
+			IkiWiki::render($file, sprintf(gettext("building %s"), $file));
+		}
 	}
 
-	# refresh/create POT and PO files as needed
 	my $updated_po_files=0;
-	foreach my $page (keys %pagesources) {
-		my $pageneedsbuild = grep { $_ eq $pagesources{$page} } @$needsbuild;
-		if (istranslatable($page)) {
-			my $file=srcfile($pagesources{$page});
-			if ($pageneedsbuild || ! -e potfile($file)) {
-				refreshpot($file);
-			}
-			my @pofiles;
-			foreach my $lang (keys %{$config{po_slave_languages}}) {
-				my $pofile=pofile($file, $lang);
-				if ($pageneedsbuild || ! -e $pofile) {
-					push @pofiles, $pofile;
-				}
-			}
-			if (@pofiles) {
-				refreshpofiles($file, @pofiles) ;
-				map { IkiWiki::rcs_add($_); } @pofiles if ($config{rcs});
-				$updated_po_files = 1;
-			}
+
+	# Refresh/create POT and PO files as needed.
+	foreach my $file (grep {istranslatablefile($_)} @rendered) {
+		my $masterfile=srcfile($file);
+		my $page=pagename($file);
+		my $updated_pot_file=0;
+
+		# Avoid touching underlay files.
+		next if $masterfile ne "$config{srcdir}/$file";
+
+		# Only refresh POT file if it does not exist, or if
+		# the source was changed: don't if only the HTML was
+		# refreshed, e.g. because of a dependency.
+		if ((grep { $_ eq $pagesources{$page} } @origneedsbuild) ||
+		    ! -e potfile($masterfile)) {
+			refreshpot($masterfile);
+			$updated_pot_file=1;
+		}
+		my @pofiles;
+		foreach my $po (pofiles($masterfile)) {
+			next if ! $updated_pot_file && -e $po;
+			next if grep { $po=~/\Q$_\E/ } @{$config{underlaydirs}};
+			push @pofiles, $po;
+		}
+		if (@pofiles) {
+			refreshpofiles($masterfile, @pofiles);
+			map { s/^\Q$config{srcdir}\E\/*//; IkiWiki::rcs_add($_) } @pofiles if $config{rcs};
+			$updated_po_files=1;
 		}
 	}
 
-	# check staged changes in and trigger a wiki refresh.
 	if ($updated_po_files) {
-		if ($config{rcs}) {
-			IkiWiki::disable_commit_hook();
-			IkiWiki::rcs_commit_staged(gettext("updated PO files"),
-				"refreshpofiles", "127.0.0.1");
-			IkiWiki::enable_commit_hook();
-			IkiWiki::rcs_update();
+		commit_and_refresh(
+			gettext("updated PO files"),
+			"IkiWiki::Plugin::po::change");
+	}
+}
+
+sub checkcontent (@) {
+	my %params=@_;
+
+	if (istranslation($params{page})) {
+		my $res = isvalidpo($params{content});
+		if ($res) {
+			return undef;
 		}
-		IkiWiki::refresh();
-		IkiWiki::saveindex();
-		# refresh module's private variables
-		%filtered=undef;
-		%translations=undef;
-		foreach my $page (keys %pagesources) {
-			istranslation($page);
+		else {
+			return "$res";
+		}
+	}
+	return undef;
+}
+
+sub canremove (@) {
+	my %params = @_;
+
+	if (istranslation($params{page})) {
+		return gettext("Can not remove a translation. If the master page is removed, ".
+			       "however, its translations will be removed as well.");
+	}
+	return undef;
+}
+
+sub canrename (@) {
+	my %params = @_;
+	my $session = $params{session};
+
+	if (istranslation($params{src})) {
+		my $masterpage = masterpage($params{src});
+		# Tell the difference between:
+		#  - a translation being renamed as a consequence of its master page
+		#    being renamed, which is allowed
+		#  - a user trying to directly rename a translation, which is forbidden
+		# by looking for the master page in the list of to-be-renamed pages we
+		# saved early in the renaming process.
+		my $orig_torename = $session->param("po_orig_torename");
+		unless (grep { $_ eq $masterpage } @{$orig_torename}) {
+			return gettext("Can not rename a translation. If the master page is renamed, ".
+				       "however, its translations will be renamed as well.");
 		}
 	}
+	return undef;
+}
 
+# As we're previewing or saving a page, the content may have
+# changed, so tell the next filter() invocation it must not be lazy.
+sub editcontent () {
+	my %params=@_;
 
-	# make existing translations depend on the corresponding master page
-	foreach my $master (keys %translations) {
-		foreach my $slave (values %{$translations{$master}}) {
-			add_depends($slave, $master);
+	unsetalreadyfiltered($params{page}, $params{page});
+	return $params{content};
+}
+
+sub formbuilder_setup (@) {
+	my %params=@_;
+	my $form=$params{form};
+	my $q=$params{cgi};
+
+	return unless defined $form->field("do");
+
+	if ($form->field("do") eq "create") {
+		# Warn the user: new pages must be written in master language.
+		my $template=template("pocreatepage.tmpl");
+		$template->param(LANG => $config{po_master_language}{name});
+		$form->tmpl_param(message => $template->output);
+	}
+	elsif ($form->field("do") eq "edit") {
+		# Remove the rename/remove buttons on slave pages.
+		# This has to be done after the rename/remove plugins have added
+		# their buttons, which is why this hook must be run last.
+		# The canrename/canremove hooks already ensure this is forbidden
+		# at the backend level, so this is only UI sugar.
+		if (istranslation($form->field("page"))) {
+			map {
+				for (my $i = 0; $i < @{$params{buttons}}; $i++) {
+					if (@{$params{buttons}}[$i] eq $_) {
+						delete  @{$params{buttons}}[$i];
+						last;
+					}
+				}
+			} qw(Rename Remove);
 		}
 	}
-} #}}}
+}
 
-sub targetpage (@) { #{{{
-	my %params = @_;
-        my $page=$params{page};
-        my $ext=$params{ext};
+sub formbuilder (@) {
+	my %params=@_;
+	my $form=$params{form};
+	my $q=$params{cgi};
 
-	if (istranslation($page)) {
-		my ($masterpage, $lang) = ($page =~ /(.*)[.]([a-z]{2})$/);
-		if (! $config{usedirs} || $page eq 'index') {
+	return unless defined $form->field("do");
+
+	# Do not allow to create pages of type po: they are automatically created.
+	# The main reason to do so is to bypass the "favor the type of linking page
+	# on page creation" logic, which is unsuitable when a broken link is clicked
+	# on a slave (PO) page.
+	# This cannot be done in the formbuilder_setup hook as the list of types is
+	# computed later.
+	if ($form->field("do") eq "create") {
+	        foreach my $field ($form->field) {
+			next unless "$field" eq "type";
+			next unless $field->type eq 'select';
+			my $orig_value = $field->value;
+			# remove po from the list of types
+			my @types = grep { $_->[0] ne 'po' } $field->options;
+			$field->options(\@types) if @types;
+			# favor the type of linking page's masterpage
+			if ($orig_value eq 'po') {
+				my ($from, $type);
+				if (defined $form->field('from')) {
+					($from)=$form->field('from')=~/$config{wiki_file_regexp}/;
+					$from = masterpage($from);
+				}
+				if (defined $from && exists $pagesources{$from}) {
+					$type=pagetype($pagesources{$from});
+				}
+				$type=$config{default_pageext} unless defined $type;
+				$field->value($type) ;
+			}
+		}
+	}
+}
+
+# ,----
+# | Injected functions
+# `----
+
+# Implement po_link_to 'current' and 'negotiated' settings.
+sub mybestlink ($$) {
+	my $page=shift;
+	my $link=shift;
+
+	return $origsubs{'bestlink'}->($page, $link)
+		if $config{po_link_to} eq "default";
+
+	my $res=$origsubs{'bestlink'}->(masterpage($page), $link);
+	my @caller = caller(1);
+	if (length $res
+	    && istranslatable($res)
+	    && istranslation($page)
+	    &&  !(exists $caller[3] && defined $caller[3]
+		  && ($caller[3] eq "IkiWiki::PageSpec::match_link"))) {
+		return $res . "." . lang($page);
+	}
+	return $res;
+}
+
+sub mybeautify_urlpath ($) {
+	my $url=shift;
+
+	my $res=$origsubs{'beautify_urlpath'}->($url);
+	if ($config{po_link_to} eq "negotiated") {
+		$res =~ s!/\Qindex.$config{po_master_language}{code}.$config{htmlext}\E$!/!;
+		$res =~ s!/\Qindex.$config{htmlext}\E$!/!;
+		map {
+			$res =~ s!/\Qindex.$_.$config{htmlext}\E$!/!;
+		} (keys %{$config{po_slave_languages}});
+	}
+	return $res;
+}
+
+sub mytargetpage ($$) {
+	my $page=shift;
+	my $ext=shift;
+
+	if (istranslation($page) || istranslatable($page)) {
+		my ($masterpage, $lang) = (masterpage($page), lang($page));
+		if (! $config{usedirs} || $masterpage eq 'index') {
 			return $masterpage . "." . $lang . "." . $ext;
 		}
 		else {
 			return $masterpage . "/index." . $lang . "." . $ext;
 		}
 	}
-	elsif (istranslatable($page)) {
-		if (! $config{usedirs} || $page eq 'index') {
-			return $page . "." . $config{po_master_language}{code} . "." . $ext;
+	return $origsubs{'targetpage'}->($page, $ext);
+}
+
+sub myurlto ($$;$) {
+	my $to=shift;
+	my $from=shift;
+	my $absolute=shift;
+
+	# workaround hard-coded /index.$config{htmlext} in IkiWiki::urlto()
+	if (! length $to
+	    && $config{po_link_to} eq "current"
+	    && istranslatable('index')) {
+		return IkiWiki::beautify_urlpath(IkiWiki::baseurl($from) . "index." . lang($from) . ".$config{htmlext}");
+	}
+	# avoid using our injected beautify_urlpath if run by cgi_editpage,
+	# so that one is redirected to the just-edited page rather than to the
+	# negociated translation; to prevent unnecessary fiddling with caller/inject,
+	# we only do so when our beautify_urlpath would actually do what we want to
+	# avoid, i.e. when po_link_to = negotiated.
+	# also avoid doing so when run by cgi_goto, so that the links on recentchanges
+	# page actually lead to the exact page they pretend to.
+	if ($config{po_link_to} eq "negotiated") {
+		my @caller = caller(1);
+		my $use_orig = 0;
+		$use_orig = 1 if (exists $caller[3] && defined $caller[3]
+				 && ($caller[3] eq "IkiWiki::cgi_editpage" ||
+				     $caller[3] eq "IkiWiki::Plugin::goto::cgi_goto")
+				 );
+		inject(name => "IkiWiki::beautify_urlpath", call => $origsubs{'beautify_urlpath'})
+			if $use_orig;
+		my $res = $origsubs{'urlto'}->($to,$from,$absolute);
+		inject(name => "IkiWiki::beautify_urlpath", call => \&mybeautify_urlpath)
+			if $use_orig;
+		return $res;
+	}
+	else {
+		return $origsubs{'urlto'}->($to,$from,$absolute)
+	}
+}
+
+sub mycgiurl (@) {
+	my %params=@_;
+
+	# slave pages have no subpages
+	if (istranslation($params{'from'})) {
+		$params{'from'} = masterpage($params{'from'});
+	}
+	return $origsubs{'cgiurl'}->(%params);
+}
+
+sub myrootpage (@) {
+	my %params=@_;
+
+	my $rootpage;
+	if (exists $params{rootpage}) {
+		$rootpage=$origsubs{'bestlink'}->($params{page}, $params{rootpage});
+		if (!length $rootpage) {
+			$rootpage=$params{rootpage};
 		}
-		else {
-			return $page . "/index." . $config{po_master_language}{code} . "." . $ext;
+	}
+	else {
+		$rootpage=masterpage($params{page});
+	}
+	return $rootpage;
+}
+
+# ,----
+# | Blackboxes for private data
+# `----
+
+{
+	my %filtered;
+
+	sub alreadyfiltered($$) {
+		my $page=shift;
+		my $destpage=shift;
+
+		return exists $filtered{$page}{$destpage}
+			 && $filtered{$page}{$destpage} eq 1;
+	}
+
+	sub setalreadyfiltered($$) {
+		my $page=shift;
+		my $destpage=shift;
+
+		$filtered{$page}{$destpage}=1;
+	}
+
+	sub unsetalreadyfiltered($$) {
+		my $page=shift;
+		my $destpage=shift;
+
+		if (exists $filtered{$page}{$destpage}) {
+			delete $filtered{$page}{$destpage};
 		}
 	}
+
+	sub resetalreadyfiltered() {
+		undef %filtered;
+	}
+}
+
+# ,----
+# | Helper functions
+# `----
+
+sub maybe_add_leading_slash ($;$) {
+	my $str=shift;
+	my $add=shift;
+	$add=1 unless defined $add;
+	return '/' . $str if $add;
+	return $str;
+}
+
+sub istranslatablefile ($) {
+	my $file=shift;
+
+	return 0 unless defined $file;
+	my $type=pagetype($file);
+	return 0 if ! defined $type || $type eq 'po';
+	return 0 if $file =~ /\.pot$/;
+	return 1 if pagespec_match(pagename($file), $config{po_translatable_pages});
 	return;
-} #}}}
+}
 
-sub tweakurlpath ($) { #{{{
-	my %params = @_;
-	my $url=$params{url};
-	if ($config{po_link_to} eq "negotiated") {
-		$url =~ s!/index.$config{po_master_language}{code}.$config{htmlext}$!/!;
+sub istranslatable ($) {
+	my $page=shift;
+
+	$page=~s#^/##;
+	return 1 if istranslatablefile($pagesources{$page});
+	return;
+}
+
+sub _istranslation ($) {
+	my $page=shift;
+
+	$page='' unless defined $page && length $page;
+	my $hasleadingslash = ($page=~s#^/##);
+	my $file=$pagesources{$page};
+	return 0 unless defined $file
+			 && defined pagetype($file)
+			 && pagetype($file) eq 'po';
+	return 0 if $file =~ /\.pot$/;
+
+	my ($masterpage, $lang) = ($page =~ /(.*)[.]([a-z]{2})$/);
+	return 0 unless defined $masterpage && defined $lang
+			 && length $masterpage && length $lang
+			 && defined $pagesources{$masterpage}
+			 && defined $config{po_slave_languages}{$lang};
+
+	return (maybe_add_leading_slash($masterpage, $hasleadingslash), $lang)
+		if istranslatable($masterpage);
+}
+
+sub istranslation ($) {
+	my $page=shift;
+
+	if (1 < (my ($masterpage, $lang) = _istranslation($page))) {
+		my $hasleadingslash = ($masterpage=~s#^/##);
+		$translations{$masterpage}{$lang}=$page unless exists $translations{$masterpage}{$lang};
+		return (maybe_add_leading_slash($masterpage, $hasleadingslash), $lang);
 	}
-	return $url;
-} #}}}
+	return "";
+}
 
-sub tweakbestlink ($$) { #{{{
-	my %params = @_;
-	my $page=$params{page};
-	my $link=$params{link};
-	if ($config{po_link_to} eq "current"
-	    && istranslatable($link)
-	    && istranslation($page)) {
-		my ($masterpage, $curlang) = ($page =~ /(.*)[.]([a-z]{2})$/);
-		return $link . "." . $curlang;
-	}
-	return $link;
-} #}}}
-
-# We use filter to convert PO to the master page's type,
-# since other plugins should not work on PO files
-sub filter (@) { #{{{
-	my %params = @_;
-	my $page = $params{page};
-	my $destpage = $params{destpage};
-	my $content = decode_utf8(encode_utf8($params{content}));
+sub masterpage ($) {
+	my $page=shift;
 
-	# decide if this is a PO file that should be converted into a translated document,
-	# and perform various sanity checks
-	if (! istranslation($page) || $filtered{$page}{$destpage}) {
-		return $content;
+	if ( 1 < (my ($masterpage, $lang) = _istranslation($page))) {
+		return $masterpage;
 	}
+	return $page;
+}
 
-	my ($masterpage, $lang) = ($page =~ /(.*)[.]([a-z]{2})$/);
-	my $file=srcfile(exists $params{file} ? $params{file} : $IkiWiki::pagesources{$page});
-	my $masterfile = srcfile($pagesources{$masterpage});
-	my (@pos,@masters);
-	push @pos,$file;
-	push @masters,$masterfile;
-	my %options = (
-			"markdown" => (pagetype($masterfile) eq 'mdwn') ? 1 : 0,
-			);
+sub lang ($) {
+	my $page=shift;
+
+	if (1 < (my ($masterpage, $lang) = _istranslation($page))) {
+		return $lang;
+	}
+	return $config{po_master_language}{code};
+}
+
+sub islanguagecode ($) {
+	my $code=shift;
+
+	return $code =~ /^[a-z]{2}$/;
+}
+
+sub otherlanguage ($$) {
+	my $page=shift;
+	my $code=shift;
+
+	return masterpage($page) if $code eq $config{po_master_language}{code};
+	return masterpage($page) . '.' . $code;
+}
+
+sub otherlanguages ($) {
+	my $page=shift;
+
+	my %ret;
+	return \%ret unless istranslation($page) || istranslatable($page);
+	my $curlang=lang($page);
+	foreach my $lang
+		($config{po_master_language}{code}, keys %{$config{po_slave_languages}}) {
+		next if $lang eq $curlang;
+		$ret{$lang}=otherlanguage($page, $lang);
+	}
+	return \%ret;
+}
+
+sub potfile ($) {
+	my $masterfile=shift;
+
+	(my $name, my $dir, my $suffix) = fileparse($masterfile, qr/\.[^.]*/);
+	$dir='' if $dir eq './';
+	return File::Spec->catpath('', $dir, $name . ".pot");
+}
+
+sub pofile ($$) {
+	my $masterfile=shift;
+	my $lang=shift;
+
+	(my $name, my $dir, my $suffix) = fileparse($masterfile, qr/\.[^.]*/);
+	$dir='' if $dir eq './';
+	return File::Spec->catpath('', $dir, $name . "." . $lang . ".po");
+}
+
+sub pofiles ($) {
+	my $masterfile=shift;
+
+	return map pofile($masterfile, $_), (keys %{$config{po_slave_languages}});
+}
+
+sub refreshpot ($) {
+	my $masterfile=shift;
+
+	my $potfile=potfile($masterfile);
+	my %options = ("markdown" => (pagetype($masterfile) eq 'mdwn') ? 1 : 0);
 	my $doc=Locale::Po4a::Chooser::new('text',%options);
-	$doc->process(
-		'po_in_name'	=> \@pos,
-		'file_in_name'	=> \@masters,
-		'file_in_charset'  => 'utf-8',
-		'file_out_charset' => 'utf-8',
-	) or error("[po/filter:$file]: failed to translate");
-	my $tmpfh = File::Temp->new(TEMPLATE => "/tmp/ikiwiki-po-filter-out.XXXXXXXXXX");
-	my $tmpout = $tmpfh->filename;
-	$doc->write($tmpout) or error("[po/filter:$file] could not write $tmpout");
-	$content = readfile($tmpout) or error("[po/filter:$file] could not read $tmpout");
-	$filtered{$page}{$destpage}=1;
-	return $content;
-} #}}}
+	$doc->{TT}{utf_mode} = 1;
+	$doc->{TT}{file_in_charset} = 'utf-8';
+	$doc->{TT}{file_out_charset} = 'utf-8';
+	$doc->read($masterfile);
+	# let's cheat a bit to force porefs option to be passed to
+	# Locale::Po4a::Po; this is undocument use of internal
+	# Locale::Po4a::TransTractor's data, compulsory since this module
+	# prevents us from using the porefs option.
+	$doc->{TT}{po_out}=Locale::Po4a::Po->new({ 'porefs' => 'none' });
+	$doc->{TT}{po_out}->set_charset('utf-8');
+	# do the actual work
+	$doc->parse;
+	IkiWiki::prep_writefile(basename($potfile),dirname($potfile));
+	$doc->writepo($potfile);
+}
 
-sub htmlize (@) { #{{{
-	my %params=@_;
-	my $page = $params{page};
-	my $content = $params{content};
-	my ($masterpage, $lang) = ($page =~ /(.*)[.]([a-z]{2})$/);
-	my $masterfile = srcfile($pagesources{$masterpage});
+sub refreshpofiles ($@) {
+	my $masterfile=shift;
+	my @pofiles=@_;
 
-	# force content to be htmlize'd as if it was the same type as the master page
-	return IkiWiki::htmlize($page, $page, pagetype($masterfile), $content);
-} #}}}
+	my $potfile=potfile($masterfile);
+	if (! -e $potfile) {
+		error("po(refreshpofiles) ".sprintf(gettext("POT file (%s) does not exist"), $potfile));
+	}
 
-sub percenttranslated ($) { #{{{
+	foreach my $pofile (@pofiles) {
+		IkiWiki::prep_writefile(basename($pofile),dirname($pofile));
+
+		if (! -e $pofile) {
+			# If the po file exists in an underlay, copy it
+			# from there.
+			my ($pobase)=$pofile=~/^\Q$config{srcdir}\E\/?(.*)$/;
+			foreach my $dir (@{$config{underlaydirs}}) {
+				if (-e "$dir/$pobase") {
+					File::Copy::syscopy("$dir/$pobase",$pofile)
+						or error("po(refreshpofiles) ".
+							 sprintf(gettext("failed to copy underlay PO file to %s"),
+								 $pofile));
+				}
+			}
+		}
+
+		if (-e $pofile) {
+			system("msgmerge", "--previous", "-q", "-U", "--backup=none", $pofile, $potfile) == 0
+				or error("po(refreshpofiles) ".
+					 sprintf(gettext("failed to update %s"),
+						 $pofile));
+		}
+		else {
+			File::Copy::syscopy($potfile,$pofile)
+				or error("po(refreshpofiles) ".
+					 sprintf(gettext("failed to copy the POT file to %s"),
+						 $pofile));
+		}
+	}
+}
+
+sub buildtranslationscache() {
+	# use istranslation's side-effect
+	map istranslation($_), (keys %pagesources);
+}
+
+sub resettranslationscache() {
+	undef %translations;
+}
+
+sub flushmemoizecache() {
+	Memoize::flush_cache("istranslatable");
+	Memoize::flush_cache("_istranslation");
+	Memoize::flush_cache("percenttranslated");
+}
+
+sub urlto_with_orig_beautiful_urlpath($$) {
+	my $to=shift;
+	my $from=shift;
+
+	inject(name => "IkiWiki::beautify_urlpath", call => $origsubs{'beautify_urlpath'});
+	my $res=urlto($to, $from);
+	inject(name => "IkiWiki::beautify_urlpath", call => \&mybeautify_urlpath);
+
+	return $res;
+}
+
+sub percenttranslated ($) {
 	my $page=shift;
-	return "N/A" unless (istranslation($page));
-	my ($masterpage, $lang) = ($page =~ /(.*)[.]([a-z]{2})$/);
+
+	$page=~s/^\///;
+	return gettext("N/A") unless istranslation($page);
 	my $file=srcfile($pagesources{$page});
-	my $masterfile = srcfile($pagesources{$masterpage});
-	my (@pos,@masters);
-	push @pos,$file;
-	push @masters,$masterfile;
+	my $masterfile = srcfile($pagesources{masterpage($page)});
 	my %options = (
-			"markdown" => (pagetype($masterfile) eq 'mdwn') ? 1 : 0,
-			);
+		"markdown" => (pagetype($masterfile) eq 'mdwn') ? 1 : 0,
+	);
 	my $doc=Locale::Po4a::Chooser::new('text',%options);
 	$doc->process(
-		'po_in_name'	=> \@pos,
-		'file_in_name'	=> \@masters,
+		'po_in_name'	=> [ $file ],
+		'file_in_name'	=> [ $masterfile ],
 		'file_in_charset'  => 'utf-8',
 		'file_out_charset' => 'utf-8',
-	) or error("[po/percenttranslated:$file]: failed to translate");
+	) or error("po(percenttranslated) ".
+		   sprintf(gettext("failed to translate %s"), $page));
 	my ($percent,$hit,$queries) = $doc->stats();
+	$percent =~ s/\.[0-9]+$//;
 	return $percent;
-} #}}}
+}
 
-sub otherlanguages ($) { #{{{
+sub languagename ($) {
+	my $code=shift;
+
+	return $config{po_master_language}{name}
+		if $code eq $config{po_master_language}{code};
+	return $config{po_slave_languages}{$code}
+		if defined $config{po_slave_languages}{$code};
+	return;
+}
+
+sub otherlanguagesloop ($) {
 	my $page=shift;
+
 	my @ret;
-	if (istranslatable($page)) {
-		foreach my $lang (sort keys %{$translations{$page}}) {
-			my $translation = $translations{$page}{$lang};
+	my %otherpages=%{otherlanguages($page)};
+	while (my ($lang, $otherpage) = each %otherpages) {
+		if (istranslation($page) && masterpage($page) eq $otherpage) {
 			push @ret, {
-				url => urlto($translation, $page),
+				url => urlto_with_orig_beautiful_urlpath($otherpage, $page),
 				code => $lang,
-				language => $config{po_slave_languages}{$lang},
-				percent => percenttranslated($translation),
+				language => languagename($lang),
+				master => 1,
 			};
 		}
-	}
-	elsif (istranslation($page)) {
-		my ($masterpage, $curlang) = ($page =~ /(.*)[.]([a-z]{2})$/);
-		push @ret, {
-			url => urlto($masterpage, $page),
-			code => $config{po_master_language}{code},
-			language => $config{po_master_language}{name},
-			master => 1,
-		};
-		foreach my $lang (sort keys %{$translations{$masterpage}}) {
+		elsif (istranslation($otherpage)) {
 			push @ret, {
-				url => urlto($translations{$masterpage}{$lang}, $page),
+				url => urlto_with_orig_beautiful_urlpath($otherpage, $page),
 				code => $lang,
-				language => $config{po_slave_languages}{$lang},
-				percent => percenttranslated($translations{$masterpage}{$lang}),
-			} unless ($lang eq $curlang);
+				language => languagename($lang),
+				percent => percenttranslated($otherpage),
+			}
 		}
 	}
-	return @ret;
-} #}}}
+	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;
+}
 
-sub pagetemplate (@) { #{{{
-	my %params=@_;
-        my $page=$params{page};
-        my $template=$params{template};
+sub homepageurl (;$) {
+	my $page=shift;
 
-	if (istranslation($page) && $template->query(name => "percenttranslated")) {
-		$template->param(percenttranslated => percenttranslated($page));
-	}
-	if ($template->query(name => "otherlanguages")) {
-		$template->param(otherlanguages => [otherlanguages($page)]);
-		if (istranslatable($page)) {
-			foreach my $translation (values %{$translations{$page}}) {
-				add_depends($page, $translation);
-			}
+	return urlto('', $page);
+}
+
+sub ishomepage ($) {
+	my $page = shift;
+
+	return 1 if $page eq 'index';
+	map { return 1 if $page eq 'index.'.$_ } keys %{$config{po_slave_languages}};
+	return undef;
+}
+
+sub deletetranslations ($) {
+	my $deletedmasterfile=shift;
+
+	my $deletedmasterpage=pagename($deletedmasterfile);
+	my @todelete;
+	map {
+		my $file = newpagefile($deletedmasterpage.'.'.$_, 'po');
+		my $absfile = "$config{srcdir}/$file";
+		if (-e $absfile && ! -l $absfile && ! -d $absfile) {
+			push @todelete, $file;
 		}
-		elsif (istranslation($page)) {
-			my ($masterpage, $curlang) = ($page =~ /(.*)[.]([a-z]{2})$/);
-			add_depends($page, $masterpage);
-			foreach my $translation (values %{$translations{$masterpage}}) {
-				add_depends($page, $translation);
-			}
+	} keys %{$config{po_slave_languages}};
+
+	map {
+		if ($config{rcs}) {
+			IkiWiki::rcs_remove($_);
+		}
+		else {
+			IkiWiki::prune("$config{srcdir}/$_");
 		}
+	} @todelete;
+
+	if (@todelete) {
+		commit_and_refresh(
+			gettext("removed obsolete PO files"),
+			"IkiWiki::Plugin::po::deletetranslations");
 	}
-} # }}}
+}
 
-sub istranslatable ($) { #{{{
-	my $page=shift;
-	my $file=$pagesources{$page};
+sub commit_and_refresh ($$) {
+	my ($msg, $author) = (shift, shift);
 
-	if (! defined $file
-	    || (defined pagetype($file) && pagetype($file) eq 'po')
-	    || $file =~ /\.pot$/) {
-		return 0;
+	if ($config{rcs}) {
+		IkiWiki::disable_commit_hook();
+		IkiWiki::rcs_commit_staged($msg, $author, "127.0.0.1");
+		IkiWiki::enable_commit_hook();
+		IkiWiki::rcs_update();
 	}
-	return pagespec_match($page, $config{po_translatable_pages});
-} #}}}
+	# Reinitialize module's private variables.
+	resetalreadyfiltered();
+	resettranslationscache();
+	flushmemoizecache();
+	# Trigger a wiki refresh.
+	require IkiWiki::Render;
+	# without preliminary saveindex/loadindex, refresh()
+	# complains about a lot of uninitialized variables
+	IkiWiki::saveindex();
+	IkiWiki::loadindex();
+	IkiWiki::refresh();
+	IkiWiki::saveindex();
+}
 
-sub _istranslation ($) { #{{{
-	my $page=shift;
-	my $file=$pagesources{$page};
-	if (! defined $file) {
-		return IkiWiki::FailReason->new("no file specified");
-	}
+sub po_to_markup ($$) {
+	my ($page, $content) = (shift, shift);
 
-	if (! defined $file
-	    || ! defined pagetype($file)
- 	    || ! pagetype($file) eq 'po'
-	    || $file =~ /\.pot$/) {
-		return 0;
-	}
+	$content = '' unless defined $content;
+	$content = decode_utf8(encode_utf8($content));
+	# CRLF line terminators make poor Locale::Po4a feel bad
+	$content=~s/\r\n/\n/g;
 
-	my ($masterpage, $lang) = ($page =~ /(.*)[.]([a-z]{2})$/);
-	if (! defined $masterpage || ! defined $lang
-	    || ! (length($masterpage) > 0) || ! (length($lang) > 0)
-	    || ! defined $pagesources{$masterpage}
-	    || ! defined $config{po_slave_languages}{$lang}) {
-		return 0;
-	}
+	# There are incompatibilities between some File::Temp versions
+	# (including 0.18, bundled with Lenny's perl-modules package)
+	# and others (e.g. 0.20, previously present in the archive as
+	# a standalone package): under certain circumstances, some
+	# return a relative filename, whereas others return an absolute one;
+	# we here use this module in a way that is at least compatible
+	# with 0.18 and 0.20. Beware, hit'n'run refactorers!
+	my $infile = new File::Temp(TEMPLATE => "ikiwiki-po-filter-in.XXXXXXXXXX",
+				    DIR => File::Spec->tmpdir,
+				    UNLINK => 1)->filename;
+	my $outfile = new File::Temp(TEMPLATE => "ikiwiki-po-filter-out.XXXXXXXXXX",
+				     DIR => File::Spec->tmpdir,
+				     UNLINK => 1)->filename;
 
-	return istranslatable($masterpage);
-} #}}}
+	my $fail = sub ($) {
+		my $msg = "po(po_to_markup) - $page : " . shift;
+		error($msg, sub { unlink $infile, $outfile});
+	};
 
-sub istranslation ($) { #{{{
-	my $page=shift;
-	if (_istranslation($page)) {
-		my ($masterpage, $lang) = ($page =~ /(.*)[.]([a-z]{2})$/);
-		$translations{$masterpage}{$lang}=$page unless exists $translations{$masterpage}{$lang};
-		return 1;
+	writefile(basename($infile), File::Spec->tmpdir, $content)
+		or return $fail->(sprintf(gettext("failed to write %s"), $infile));
+
+	my $masterfile = srcfile($pagesources{masterpage($page)});
+	my %options = (
+		"markdown" => (pagetype($masterfile) eq 'mdwn') ? 1 : 0,
+	);
+	my $doc=Locale::Po4a::Chooser::new('text',%options);
+	$doc->process(
+		'po_in_name'	=> [ $infile ],
+		'file_in_name'	=> [ $masterfile ],
+		'file_in_charset'  => 'utf-8',
+		'file_out_charset' => 'utf-8',
+	) or return $fail->(gettext("failed to translate"));
+	$doc->write($outfile)
+		or return $fail->(sprintf(gettext("failed to write %s"), $outfile));
+
+	$content = readfile($outfile);
+
+	# Unlinking should happen automatically, thanks to File::Temp,
+	# but it does not work here, probably because of the way writefile()
+	# and Locale::Po4a::write() work.
+	unlink $infile, $outfile;
+
+	return $content;
+}
+
+# returns a SuccessReason or FailReason object
+sub isvalidpo ($) {
+	my $content = shift;
+
+	# NB: we don't use po_to_markup here, since Po4a parser does
+	# not mind invalid PO content
+	$content = '' unless defined $content;
+	$content = decode_utf8(encode_utf8($content));
+
+	# There are incompatibilities between some File::Temp versions
+	# (including 0.18, bundled with Lenny's perl-modules package)
+	# and others (e.g. 0.20, previously present in the archive as
+	# a standalone package): under certain circumstances, some
+	# return a relative filename, whereas others return an absolute one;
+	# we here use this module in a way that is at least compatible
+	# with 0.18 and 0.20. Beware, hit'n'run refactorers!
+	my $infile = new File::Temp(TEMPLATE => "ikiwiki-po-isvalidpo.XXXXXXXXXX",
+				    DIR => File::Spec->tmpdir,
+				    UNLINK => 1)->filename;
+
+	my $fail = sub ($) {
+		my $msg = '[po/isvalidpo] ' . shift;
+		unlink $infile;
+		return IkiWiki::FailReason->new("$msg");
+	};
+
+	writefile(basename($infile), File::Spec->tmpdir, $content)
+		or return $fail->(sprintf(gettext("failed to write %s"), $infile));
+
+	my $res = (system("msgfmt", "--check", $infile, "-o", "/dev/null") == 0);
+
+	# Unlinking should happen automatically, thanks to File::Temp,
+	# but it does not work here, probably because of the way writefile()
+	# and Locale::Po4a::write() work.
+	unlink $infile;
+
+	if ($res) {
+	    return IkiWiki::SuccessReason->new("valid gettext data");
 	}
-	return 0;
-} #}}}
+	return IkiWiki::FailReason->new(gettext("invalid gettext data, go back ".
+					"to previous page to continue edit"));
+}
+
+# ,----
+# | PageSpecs
+# `----
 
 package IkiWiki::PageSpec;
-use warnings;
-use strict;
-use IkiWiki 2.00;
 
-sub match_istranslation ($;@) { #{{{
+sub match_istranslation ($;@) {
 	my $page=shift;
+
 	if (IkiWiki::Plugin::po::istranslation($page)) {
 		return IkiWiki::SuccessReason->new("is a translation page");
 	}
 	else {
 		return IkiWiki::FailReason->new("is not a translation page");
 	}
-} #}}}
+}
 
-sub match_istranslatable ($;@) { #{{{
+sub match_istranslatable ($;@) {
 	my $page=shift;
+
 	if (IkiWiki::Plugin::po::istranslatable($page)) {
 		return IkiWiki::SuccessReason->new("is set as translatable in po_translatable_pages");
 	}
 	else {
 		return IkiWiki::FailReason->new("is not set as translatable in po_translatable_pages");
 	}
-} #}}}
+}
 
-sub match_lang ($$;@) { #{{{
+sub match_lang ($$;@) {
 	my $page=shift;
 	my $wanted=shift;
-	my $regexp=IkiWiki::glob2re($wanted);
-	my $lang;
-	my $masterpage;
 
-	if (IkiWiki::Plugin::po::istranslation($page)) {
-		($masterpage, $lang) = ($page =~ /(.*)[.]([a-z]{2})$/);
-	}
-	else {
-		$lang = $config{po_master_language}{code};
-	}
-
-	if ($lang!~/^$regexp$/i) {
+	my $regexp=IkiWiki::glob2re($wanted);
+	my $lang=IkiWiki::Plugin::po::lang($page);
+	if ($lang !~ /^$regexp$/i) {
 		return IkiWiki::FailReason->new("file language is $lang, not $wanted");
 	}
 	else {
 		return IkiWiki::SuccessReason->new("file language is $wanted");
 	}
-} #}}}
+}
 
-sub match_currentlang ($$;@) { #{{{
+sub match_currentlang ($$;@) {
 	my $page=shift;
 	shift;
 	my %params=@_;
-	my ($currentmasterpage, $currentlang, $masterpage, $lang);
 
 	return IkiWiki::FailReason->new("no location provided") unless exists $params{location};
 
-	if (IkiWiki::Plugin::po::istranslation($params{location})) {
-		($currentmasterpage, $currentlang) = ($params{location} =~ /(.*)[.]([a-z]{2})$/);
-	}
-	else {
-		$currentlang = $config{po_master_language}{code};
-	}
-
-	if (IkiWiki::Plugin::po::istranslation($page)) {
-		($masterpage, $lang) = ($page =~ /(.*)[.]([a-z]{2})$/);
-	}
-	else {
-		$lang = $config{po_master_language}{code};
-	}
+	my $currentlang=IkiWiki::Plugin::po::lang($params{location});
+	my $lang=IkiWiki::Plugin::po::lang($page);
 
 	if ($lang eq $currentlang) {
 		return IkiWiki::SuccessReason->new("file language is the same as current one, i.e. $currentlang");
@@ -503,6 +1215,6 @@ sub match_currentlang ($$;@) { #{{{
 	else {
 		return IkiWiki::FailReason->new("file language is $lang, whereas current language is $currentlang");
 	}
-} #}}}
+}
 
 1