--- /dev/null
+package Text::Tradition::Language::English;
+
+use strict;
+use warnings;
+use Encode qw/ encode_utf8 decode_utf8 /;
+use IPC::Run qw/ run /;
+use Lingua::TagSet::TreeTagger;
+use Module::Load;
+use Text::Tradition::Collation::Reading::Lexeme;
+use Text::Tradition::Collation::Reading::WordForm;
+use TryCatch;
+
+my $MORPHDIR = '/Users/tla/Projects/morphology';
+
+=head1 NAME
+
+Text::Tradition::Language::English - language-specific module for English
+
+=head1 DESCRIPTION
+
+Implements morphology lookup for English words in context. This module
+depends on the TreeTagger software
+(L<http://www.ims.uni-stuttgart.de/projekte/corplex/TreeTagger/>), which is
+(for now) expected to be installed in $MORPHDIR/TreeTagger.
+
+=head1 SUBROUTINES
+
+=head2 lemmatize( $text )
+
+Evaluates the string using the TreeTagger, and returns the results.
+
+=begin testing
+
+binmode STDOUT, ':utf8';
+use Text::Tradition;
+use_ok( 'Text::Tradition::Language::English' );
+
+=end testing
+
+=cut
+
+sub lemmatize {
+ my $tradition = shift;
+
+ # Given a tradition, lemmatize it witness by witness and see what we get.
+ my $workdir = File::Temp->newdir();
+ my $c = $tradition->collation;
+ # First, clear out all existing lexemes from the readings. Save the
+ # path as long as we went to the trouble of generating it.
+ my %witness_paths;
+ foreach my $wit ( $tradition->witnesses ) {
+ my @sigla = ( $wit->sigil );
+ push( @sigla, $wit->sigil . $c->ac_label ) if $wit->is_layered;
+ foreach my $sig ( @sigla ) {
+ my @path = grep { !$_->is_meta }
+ $c->reading_sequence( $c->start, $c->end, $sig );
+ map { $_->clear_lexemes } @path;
+ $witness_paths{$sig} = \@path;
+ }
+ }
+
+ foreach my $sig ( keys %witness_paths ) {
+ # Get the text as a sequence of readings and as a string
+ print STDERR "Morphologizing witness $sig\n";
+ _lemmatize_sequence( undef, @{$witness_paths{$sig}} );
+ }
+}
+
+sub _update_reading_lexemes {
+ my( $replace, $reading, @lexemes ) = @_;
+ if( $reading->has_lexemes && !$replace ) {
+ # We need to merge what is in @lexemes with what we have already.
+ my @oldlex = $reading->lexemes;
+ my $cmp1 = join( '||', map { $_->string } @oldlex );
+ my $cmp2 = join( '||', map { $_->string } @lexemes );
+ if ( @oldlex == @lexemes && $cmp1 eq $cmp2 ) {
+ # The lexeme strings are the same, so merge the possible
+ # word forms from new to old.
+ foreach my $i ( 0 .. $#lexemes ) {
+ my $ol = $oldlex[$i];
+ my $nl = $lexemes[$i];
+ my %ofw;
+ map { $ofw{$_->to_string} = 1 } $ol->matching_forms;
+ foreach my $form ( $nl->matching_forms ) {
+ unless( $ofw{$form->to_string} ) {
+ print STDERR "Adding form " . $form->to_string .
+ " to lexeme " . $nl->string . " at $reading\n";
+ $ol->add_matching_form( $form );
+ $ol->is_disambiguated(0);
+ }
+ }
+ }
+ } else {
+ warn "Lexeme layout for $reading changed; replacing the lot";
+ $reading->clear_lexemes;
+ $reading->add_lexeme( @lexemes );
+ }
+ } else {
+ $reading->clear_lexemes if $replace;
+ $reading->add_lexeme( @lexemes );
+ }
+}
+
+=head2 reading_lookup( $rdg[, $rdg, ...] )
+
+Looks up one or more readings using the Flemm package, and returns the
+possible results. This uses the same logic as L<lemmatize> above for the
+entire tradition, but can also be used to (re-)analyze individual readings.
+
+=cut
+
+sub reading_lookup {
+ return _lemmatize_sequence( 1, @_ );
+}
+
+sub _lemmatize_sequence {
+ my( $replace, @path ) = @_;
+ my $tagresult = _treetag_string( _text_from_path( 1, @path ) );
+ if( $tagresult ) {
+ # Map the tagged words onto the original readings, splitting
+ # them up into lexemes where necessary.
+ # NOTE we can have multiple lexemes in a reading, but not
+ # multiple readings to a lexeme.
+ my @tags = split( /\n/, $tagresult );
+ my @lexemes;
+ my $curr_rdg = shift @path;
+ my @curr_lexemes;
+ my $unused_rdg_part;
+ foreach my $tag ( @tags ) {
+ # Get the original word
+ my( $lexeme, @rest ) = split( /\t/, $tag );
+ # Lemmatize the whole
+ my @forms = _parse_wordform( $tag );
+ my $lexobj = Text::Tradition::Collation::Reading::Lexeme->new(
+ 'string' => $lexeme, 'language' => 'English',
+ 'wordform_matchlist' => \@forms );
+ # Find the next non-meta reading
+ while( $curr_rdg && $curr_rdg->is_meta ) {
+ $curr_rdg = shift @path;
+ }
+ unless( $curr_rdg ) {
+ warn "Ran out of readings in sequence at $lexeme";
+ last;
+ }
+ my $curr_rdg_text = $curr_rdg->has_normal_form
+ ? $curr_rdg->normal_form : $curr_rdg->text;
+ if( $unused_rdg_part &&
+ $unused_rdg_part =~ /^\Q$lexeme\E(\s*)(.*)$/ ) {
+ # Nth part of curr_rdg
+ $unused_rdg_part = $2;
+ push( @curr_lexemes, $lexobj );
+ } elsif( $curr_rdg_text =~ /^\Q$lexeme\E(\s*)(.*)$/ ) {
+ # Flag an error if there is already an unused reading part.
+ warn "Skipped over unused text $unused_rdg_part at $curr_rdg"
+ if $unused_rdg_part;
+ $unused_rdg_part = $2; # will be empty if the whole reading matched
+ push( @curr_lexemes, $lexobj );
+ } else {
+ # We do not cope with the idea of a lexeme being
+ # spread across multiple readings.
+ warn "Word sequence changed unexpectedly in text";
+ # See if we can find a matching reading
+ my @lookahead;
+ my $matched;
+ while( my $nr = shift @path ) {
+ my $nrtext = $nr->has_normal_form ? $nr->normal_form : $nr->text;
+ if( $nrtext =~ /^\Q$lexeme\E/ ) {
+ $curr_rdg = $lookahead[-1] if @lookahead;
+ $matched = 1;
+ last;
+ } else {
+ push( @lookahead, $nr );
+ }
+ }
+ # No match? Restore the state we had
+ unless( $matched ) {
+ unshift( @path, @lookahead );
+ }
+ # Trigger a move
+ $unused_rdg_part = '';
+ }
+
+ unless( $unused_rdg_part ) {
+ # Record the lexemes for the given reading.
+ #print STDERR sprintf( "Adding lexeme(s) %s to reading %s (%s)\n",
+ # join( ' ', map { $_->string } @curr_lexemes ),
+ # $curr_rdg->id, $curr_rdg->text );
+ _update_reading_lexemes( $replace, $curr_rdg, @curr_lexemes );
+ $curr_rdg = shift @path;
+ @curr_lexemes = ();
+ }
+ }
+ }
+}
+
+# Utility function so that we can cheat and use it when we need both the path
+# and its text.
+sub _text_from_path {
+ my( $normalize, @path ) = @_;
+ my $pathtext = '';
+ my $last;
+ foreach my $r ( @path ) {
+ unless ( $r->join_prior || !$last || $last->join_next ) {
+ $pathtext .= ' ';
+ }
+ $pathtext .= ( $normalize && $r->has_normal_form )
+ ? $r->normal_form : $r->text;
+ $last = $r;
+ }
+ return $pathtext;
+}
+
+# Utility function that actually calls the tree tagger.
+sub _treetag_string {
+ my( $text ) = @_;
+ my $wittext = encode_utf8( $text );
+ # Then see if we have TreeTagger
+ my $taggercmd = "$MORPHDIR/TreeTagger/cmd/tree-tagger-english";
+ unless( -f $taggercmd ) {
+ warn "Cannot do English word lemmatization without TreeTagger";
+ return;
+ }
+ # OK, we can run it then.
+ my @cmd = ( $taggercmd );
+ my( $tagresult, $err ); # Capture the output and error
+ run( \@cmd, \$wittext, \$tagresult, \$err );
+ # TODO check for error
+ return decode_utf8( $tagresult );
+}
+
+# Utility function to turn a TreeTagger result into a WordForm
+sub _parse_wordform {
+ my $tagresult = shift;
+ my( $orig, $tag, $lemma ) = split( /\t/, $tagresult );
+ my $morphobj = Lingua::TagSet::TreeTagger->tag2structure( $tag );
+ if( $morphobj ) {
+ return Text::Tradition::Collation::Reading::WordForm->new(
+ 'language' => 'English',
+ 'lemma' => $lemma,
+ 'morphology' => $morphobj,
+ );
+ } else {
+ warn "No morphology found for word: $_";
+ }
+}
+
+1;
+
+=head2 TODO
+
+=over
+
+=item * Handle package dependencies more gracefully
+
+=item * Refactor English/French use of TreeTagger into its own util package
+
+=back
+
+=head1 LICENSE
+
+This package is free software and is provided "as is" without express
+or implied warranty. You can redistribute it and/or modify it under
+the same terms as Perl itself.
+
+=head1 AUTHOR
+
+Tara L Andrews E<lt>aurum@cpan.orgE<gt>