* meta: Drop support for "meta link", since supporting this for internal

  links required meta to be run during scan, which complicated its data
  storage, since it had to clear data stored during the scan pass to avoid
  duplicating it during the normal preprocessing pass.
* If you used "meta link", you should switch to either "meta openid" (for
  openid delegations), or tags (for internal, invisible links). I assume
  that nobody really used "meta link" for external, non-openid links, since
  the htmlscrubber ate those. (Tell me differently and I'll consider bringing
  back that support.)
* meta: Improved data storage.
* meta: Drop the hackish filter hook that was used to clear
  stored data before preprocessing, this hack was ugly, and broken (cf:
  liw's disappearing openids).
* aggregate: Convert filter hook to a needsbuild hook.

2 files changed, 80 insertions, 83 deletions

diff --git a/IkiWiki/Plugin/aggregate.pm b/IkiWiki/Plugin/aggregate.pm
index ea27fc199..0869d6d8f 100644
--- a/IkiWiki/Plugin/aggregate.pm
+++ b/IkiWiki/Plugin/aggregate.pm
@@ -17,7 +17,7 @@ my %guids;
 sub import { #{{{
 	hook(type => "getopt", id => "aggregate", call => \&getopt);
 	hook(type => "checkconfig", id => "aggregate", call => \&checkconfig);
-	hook(type => "filter", id => "aggregate", call => \&filter);
+	hook(type => "needsbuild", id => "aggregate", call => \&needsbuild);
 	hook(type => "preprocess", id => "aggregate", call => \&preprocess);
         hook(type => "delete", id => "aggregate", call => \&delete);
 	hook(type => "savestate", id => "aggregate", call => \&savestate);
@@ -49,16 +49,17 @@ sub checkconfig () { #{{{
 	}
 } #}}}
 
-sub filter (@) { #{{{
-	my %params=@_;
-	my $page=$params{page};
-
-	loadstate(); # if not already loaded
-	# Mark all feeds originating on this page as removable;
-	# preprocess will unmark those that still exist.
-	remove_feeds($page);
+sub needsbuild (@) { #{{{
+	my $needsbuild=shift;
 
-	return $params{content};
+	foreach my $page (keys %pagestate) {
+		if (grep { $_ eq $pagesources{$page} } @$needsbuild) {
+			loadstate(); # if not already loaded
+			# Mark all feeds originating on this page as removable;
+			# preprocess will unmark those that still exist.
+			remove_feeds($page);
+		}
+	}
 } # }}}
 
 sub preprocess (@) { #{{{
diff --git a/IkiWiki/Plugin/meta.pm b/IkiWiki/Plugin/meta.pm
index 4aa545a93..8555e1109 100644
--- a/IkiWiki/Plugin/meta.pm
+++ b/IkiWiki/Plugin/meta.pm
@@ -15,19 +15,24 @@ my %license;
 my %copyright;
 
 sub import { #{{{
-	hook(type => "preprocess", id => "meta", call => \&preprocess, scan => 1);
-	hook(type => "filter", id => "meta", call => \&filter);
+	hook(type => "needsbuild", id => "meta", call => \&needsbuild);
+	hook(type => "preprocess", id => "meta", call => \&preprocess);
 	hook(type => "pagetemplate", id => "meta", call => \&pagetemplate);
 } # }}}
 
-sub filter (@) { #{{{
-	my %params=@_;
-	
-	$meta{$params{page}}='';
-	delete $pagestate{$params{page}}{meta}{redir};
-
-	return $params{content};
-} # }}}
+sub needsbuild (@) { #{{{
+	my $needsbuild=shift;
+	foreach my $page (keys %pagestate) {
+		if (exists $pagestate{$page}{meta}) {
+			if (grep { $_ eq $pagesources{$page} } @$needsbuild) {
+				# remove state, it will be re-added
+				# if the preprocessor directive is still
+				# there during the rebuild
+				delete $pagestate{$page}{meta};
+			}
+		}
+	}
+}
 
 sub scrub ($) { #{{{
 	if (IkiWiki::Plugin::htmlscrubber->can("sanitize")) {
@@ -39,9 +44,7 @@ sub scrub ($) { #{{{
 } #}}}
 
 sub preprocess (@) { #{{{
-	if (! @_) {
-		return "";
-	}
+	return "" unless @_;
 	my %params=@_;
 	my $key=shift;
 	my $value=$params{$key};
@@ -53,25 +56,56 @@ sub preprocess (@) { #{{{
 	delete $params{preview};
 
 	eval q{use HTML::Entities};
-	# Always dencode, even if encoding later, since it might not be
+	# Always decode, even if encoding later, since it might not be
 	# fully encoded.
 	$value=decode_entities($value);
 
-	if ($key eq 'link') {
-		if (%params) {
-			$meta{$page}.=scrub("<link href=\"".encode_entities($value)."\" ".
-				join(" ", map {
-					encode_entities($_)."=\"".encode_entities(decode_entities($params{$_}))."\""
-				} keys %params).
-				" />\n");
+	if ($key eq 'title') {
+		$title{$page}=HTML::Entities::encode_numeric($value);
+	}
+	elsif ($key eq 'permalink') {
+		$permalink{$page}=$value;
+		push @{$meta{$page}}, scrub('<link rel="bookmark" href="'.encode_entities($value).'" />');
+	}
+	elsif ($key eq 'date') {
+		eval q{use Date::Parse};
+		if (! $@) {
+			my $time = str2time($value);
+			$IkiWiki::pagectime{$page}=$time if defined $time;
 		}
-		else {
-			# hidden WikiLink
-			push @{$links{$page}}, $value;
+	}
+	elsif ($key eq 'stylesheet') {
+		my $rel=exists $params{rel} ? $params{rel} : "alternate stylesheet";
+		my $title=exists $params{title} ? $params{title} : $value;
+		# adding .css to the value prevents using any old web
+		# editable page as a stylesheet
+		my $stylesheet=bestlink($page, $value.".css");
+		if (! length $stylesheet) {
+			return "[[meta ".gettext("stylesheet not found")."]]";
+		}
+		push @{$meta{$page}}, '<link href="'.urlto($stylesheet, $page).
+			'" rel="'.encode_entities($rel).
+			'" title="'.encode_entities($title).
+			"\" type=\"text/css\" />";
+	}
+	elsif ($key eq 'openid') {
+		if (exists $params{server}) {
+			push @{$meta{$page}}, '<link href="'.encode_entities($params{server}).
+				'" rel="openid.server" />';
 		}
+		push @{$meta{$page}}, '<link href="'.encode_entities($value).
+			'" rel="openid.delegate" />';
+	}
+	elsif ($key eq 'license') {
+		push @{$meta{$page}}, '<link rel="license" href="#page_license" />';
+		$license{$page}=$value;
+	}
+	elsif ($key eq 'copyright') {
+		push @{$meta{$page}}, '<link rel="copyright" href="#page_copyright" />';
+		$copyright{$page}=$value;
 	}
 	elsif ($key eq 'redir') {
-		return "" if $destpage ne $page;
+		return "" if $page ne $destpage;
 		my $safe=0;
 		if ($value !~ /^\w+:\/\//) {
 			add_depends($page, $value);
@@ -103,55 +137,14 @@ sub preprocess (@) { #{{{
 		if (! $safe) {
 			$redir=scrub($redir);
 		}
-		$meta{$page}.=$redir;
-	}
-	elsif ($key eq 'title') {
-		$title{$page}=HTML::Entities::encode_numeric($value);
-	}
-	elsif ($key eq 'permalink') {
-		$permalink{$page}=$value;
-		$meta{$page}.=scrub("<link rel=\"bookmark\" href=\"".encode_entities($value)."\" />\n");
-	}
-	elsif ($key eq 'date') {
-		eval q{use Date::Parse};
-		if (! $@) {
-			my $time = str2time($value);
-			$IkiWiki::pagectime{$page}=$time if defined $time;
-		}
-	}
-	elsif ($key eq 'stylesheet') {
-		my $rel=exists $params{rel} ? $params{rel} : "alternate stylesheet";
-		my $title=exists $params{title} ? $params{title} : $value;
-		# adding .css to the value prevents using any old web
-		# editable page as a stylesheet
-		my $stylesheet=bestlink($page, $value.".css");
-		if (! length $stylesheet) {
-			return "[[meta ".gettext("stylesheet not found")."]]";
-		}
-		$meta{$page}.='<link href="'.urlto($stylesheet, $page).
-			'" rel="'.encode_entities($rel).
-			'" title="'.encode_entities($title).
-			"\" type=\"text/css\" />\n";
-	}
-	elsif ($key eq 'openid') {
-		if (exists $params{server}) {
-			$meta{$page}.='<link href="'.encode_entities($params{server}).
-				"\" rel=\"openid.server\" />\n";
-		}
-		$meta{$page}.='<link href="'.encode_entities($value).
-			"\" rel=\"openid.delegate\" />\n";
+		push @{$meta{$page}}, $redir;
 	}
-	elsif ($key eq 'license') {
-		$meta{$page}.="<link rel=\"license\" href=\"#page_license\" />\n";
-		$license{$page}=$value;
-	}
-	elsif ($key eq 'copyright') {
-		$meta{$page}.="<link rel=\"copyright\" href=\"#page_copyright\" />\n";
-		$copyright{$page}=$value;
+	elsif ($key eq 'link') {
+		return "[[meta ".gettext("link is no longer supported")."]]";
 	}
 	else {
-		$meta{$page}.=scrub("<meta name=\"".encode_entities($key).
-			"\" content=\"".encode_entities($value)."\" />\n");
+		push @{$meta{$page}}, scrub('<meta name="'.encode_entities($key).
+			'" content="'.encode_entities($value).'" />');
 		if ($key eq 'author') {
 			$author{$page}=$value;
 		}
@@ -169,8 +162,11 @@ sub pagetemplate (@) { #{{{
         my $destpage=$params{destpage};
         my $template=$params{template};
 
-	$template->param(meta => $meta{$page})
-		if exists $meta{$page} && $template->query(name => "meta");
+	if (exists $meta{$page} && $template->query(name => "meta")) {
+		# avoid duplicate meta lines
+		my %seen;
+		$template->param(meta => join("\n", grep { (! $seen{$_}) && ($seen{$_}=1) } @{$meta{$page}}));
+	}
 	if (exists $title{$page} && $template->query(name => "title")) {
 		$template->param(title => $title{$page});
 		$template->param(title_overridden => 1);