1 files changed, 128 insertions, 0 deletions
diff --git a/pandoc-emphasis b/pandoc-emphasis
new file mode 100755
index 0000000..2d61514
--- /dev/null
+++ b/pandoc-emphasis
@@ -0,0 +1,128 @@
+#!/usr/bin/perl
+
+# emphasis + doublequote means technical or foreign term.
+# doublequote + emphasis means title.
+
+use Moops -strict;
+
+use feature qw(switch);
+no if $] >= 5.018, warnings => "experimental::smartmatch";
+
+use Log::Contextual::LogDispatchouli qw( :log set_logger );
+use Log::Dispatchouli;
+use Pandoc::Filter 0.06;
+use Pandoc::Elements;
+
+my $ld = Log::Dispatchouli->new({
+	ident       => 'pandoc-emphasis',
+	to_stderr   => 1,
+	debug       => ($ENV{PANDOC_DEBUG}),
+	quiet_fatal => 'stdout',
+});
+set_logger $ld;
+
+class Window {
+	use Pandoc::Filter;
+
+	has view => {
+		is => 'rw',
+		isa => Object,
+	};
+	has ledge => {
+		is => 'rw',
+		isa => Maybe[Object],
+	};
+	method set_view ( Object $object ) {
+		$self->view($object);
+	}
+	method peek_at_ledge () {
+		return
+			unless ( $self->ledge );
+		my $value = stringify( $self->ledge );
+		$value = $self->ledge->content;
+		return $value;
+	}
+	method clear_ledge () {
+		$self->ledge(undef);
+	}
+	method my $recall_from_ledge () {
+		my $oldview = $self->ledge;
+		$self->clear_ledge;
+		return $oldview;
+	}
+	method describe_view () {
+		return [ $self->$recall_from_ledge, $self->view ]
+			if ( $self->ledge );
+		return;
+	}
+	method interpret_view ( Object $interpretation ) {
+		return [ $self->$recall_from_ledge, $interpretation ]
+			if ( $self->$recall_from_ledge );
+		return [ $interpretation ];
+	}
+	method suppress_view () {
+		return [ $self->$recall_from_ledge ]
+			if ( $self->ledge );
+		return [];
+	}
+	method postpone_view () {
+		$self->ledge( $self->view );
+		return [];
+	}
+}
+
+my $window = Window->new;
+
+my ($title, $foreign);
+
+pandoc_filter(
+	\&emphasis,
+);
+
+sub emphasis {
+	my $self = shift;
+	return unless ( $self->name =~ /Str|Emph/ );
+	if ( $self->name eq 'Emph' ) {
+		$window->set_view($self);
+		given ( stringify($self) ) {
+			when (/^[^\"]+$/) {
+				if ( $window->peek_at_ledge() eq '"' ) {
+					$window->clear_ledge();
+					$title++;
+# FIXME: LaTeX-encode text
+					log_debug { 'emphasis →title: ' . $_ };
+					return $window->interpret_view(
+						RawInline( 'latex',
+						'\\title{' . $_ . '}' ));
+				}
+			}
+			when (/^\"([^\"]+)\"$/) {
+# FIXME: LaTeX-encode text
+				log_debug { 'emphasis →foreign: ' . $_ };
+				return $window->interpret_view(
+					RawInline( 'latex',
+					'\\foreign{' . $1 . '}' ));
+			}
+		}
+		return $window->describe_view();
+	}
+	if ( $self->name eq 'Str' ) {
+		$window->set_view($self);
+		given ( $self->content ) {
+			when ('"') {
+				if ($title) {
+					$title--;
+					return $window->suppress_view();
+				};
+				return $window->postpone_view();
+			}
+		}
+		$window->clear_ledge();
+		if ($title) {
+			log_info { "emphasis odd after title markup." };
+			$title--;
+		}
+		return $window->describe_view();
+	}
+	return;
+}