package Alex;

# search.cgi - search a solr/lucene index via a web browser

# Eric Lease Morgan <eric_morgan@infomotions.com>

# December  20, 2008 - first investigations
# December  22, 2008 - added facets, a pager, icons, and bunches o' stuff
# January   31, 2009 - turned it into a mod_perl module
# February   1, 2009 - added title, author, subject, and synonym queries
# March     13, 2009 - put into production, for better or for worse
# April      4, 2009 - added commify and expandable creator/subject facets
# April      5, 2009 - sorted creator/subject facets; changed long links to words
# August    16, 2009 - added browse by subject/tag
# August    21, 2009 - fixed bad syntax bug; should get few, if not zero, 500 errors; Mom's birthday
# September 24, 2009 - started adding snippets and sorting
# October    2, 2009 - made dismax the defult; implemented filter queries; tweaked sorting
# August    18, 2010 - added accordian widget to facets div; kewl eye candy


# define
use constant ROOT         => '/var/www/html/main/alex';
use constant SOLR         => 'http://localhost:8983/solr/alex';
use constant TEMPLATE     => ROOT . '/etc/template.txt';
use constant RESULTS      => ROOT . '/etc/results.txt';
use constant HOME         => ROOT . '/etc/home.txt';
use constant ROWS         => 25;
use constant MINCOUNT     =>  2;
use constant POSES        => qw(n v a s r);
use constant NAME_LIST    => ROOT . '/etc/name_LETTER.txt';
use constant NAME_PAGE    => ROOT . '/etc/name-page.txt';
use constant SUBJECT_LIST => ROOT . '/etc/subject_LETTER.txt';
use constant SUBJECT_PAGE => ROOT . '/etc/subject-page.txt';
use constant TITLE_LIST   => ROOT . '/etc/titles_LETTER.txt';
use constant TITLE_PAGE   => ROOT . '/etc/title-page.txt';
use constant FORM         => ROOT . '/etc/form.txt';
use constant FORMSMALL    => ROOT . '/etc/form-small.txt';

# require
use Apache2::Const -compile => qw( OK );
use strict;
use CGI;
use Lingua::Wordnet;
use WebService::Solr;
require ( ROOT . '/lib/subroutines.pl' );


sub handler {

	# initalize
	my $r    = shift;
	my $solr = WebService::Solr->new( SOLR );
	my $cgi  = CGI->new;
	my $html = '';
	
	# get the command
	my $cmd = $cgi->param( 'cmd' );

	# branch accordingly
	if ( ! $cmd ) {
	
		# display the home page and quit
		$html = &slurp( TEMPLATE );
		$html =~ s/##CONTENT##/&slurp( HOME )/e;
		$html =~ s/##FORM##/&slurp( FORM )/ge;
		$html =~ s/##FORMSMALL##//ge;
		$html =~ s/##QUERY##//ge;
	
	}
		
	# subject/tag index
	elsif ( $cmd eq 'tags' ) {
	
		# get the list to display
		my $letter = $cgi->param( 'ltr' );
		if ( ! $letter ) { $letter = chr( int( rand( 26 )) + 65 ) }
		my $subject_list = SUBJECT_LIST;
		$subject_list =~ s/LETTER/$letter/;
		
		# display the list
		$html = &slurp( TEMPLATE );
		$html =~ s/##CONTENT##/&slurp( SUBJECT_PAGE )/e;
		$html =~ s/##TAGLIST##/&slurp( $subject_list )/e;
		$html =~ s/##FORMSMALL##/&slurp( FORMSMALL )/e;
		$html =~ s/##QUERY##//;
		$html =~ s/##GOOGLE##//ge;
		
	}

	# name index
	elsif ( $cmd eq 'names' ) {
	
		# get the list to display
		my $letter = $cgi->param( 'ltr' );
		if ( ! $letter ) { $letter = chr( int( rand( 26 )) + 65 ) }
		my $name_list = NAME_LIST;
		$name_list =~ s/LETTER/$letter/;
		
		# display the list
		$html = &slurp( TEMPLATE );
		$html =~ s/##CONTENT##/&slurp( NAME_PAGE )/e;
		$html =~ s/##NAMELIST##/&slurp( $name_list )/e;
		$html =~ s/##FORMSMALL##/&slurp( FORMSMALL )/e;
		$html =~ s/##QUERY##//;
		$html =~ s/##GOOGLE##//ge;
		
	}

	# title index
	elsif ( $cmd eq 'titles' ) {
	
		# get the list to display
		my $letter = $cgi->param( 'ltr' );
		if ( ! $letter ) { $letter = chr( int( rand( 26 )) + 65 ) }
		my $title_list = TITLE_LIST;
		$title_list =~ s/LETTER/$letter/;
		
		# display the home page
		$html = &slurp(TEMPLATE);
		$html =~ s/##CONTENT##/&slurp( TITLE_PAGE )/e;
		$html =~ s/##FORMSMALL##/&slurp( FORMSMALL )/e;
		$html =~ s/##TITLELIST##/&slurp( $title_list )/e;
		$html =~ s/##QUERY##//;
		$html =~ s/##GOOGLE##//ge;
		
	}


	elsif ( $cmd eq 'search' ) {
	
		# get the input
		my $query  = $cgi->param( 'query' );
		my $start  = $cgi->param( 'start' );
		my $sort   = $cgi->param( 'sort' );
		my $params = $cgi->query_string;

		# calculate start
		if ( ! $start ) { $start = 0 }
		
		# calculate sort
		if ( ! $sort ) { $sort = 'score desc' }
		
		# build the search options
		my %search_options = ();
		$search_options{ 'start' }          = $start;
		$search_options{ 'rows' }           = ROWS;
		$search_options{ 'facet' }          = 'true';
		$search_options{ 'facet.field' }    = [ 'type', 'facet_creator', 'facet_subject', 'repository' ];
		$search_options{ 'facet.mincount' } = MINCOUNT;
		$search_options{ 'sort' }           = $sort;
		if ( $cgi->param( 'fq') ) { $search_options{ 'fq' } = [ $cgi->param( 'fq') ] };
		
		# do the work; search
		my $response = $solr->search( $query, \%search_options );
		
		# types facet
		my %types       = &get_facets( $response->facet_counts->{ facet_fields }->{ type } );
		my $types_facet = '';
		foreach ( sort( keys( %types ))) {
		
			my $link = $cgi->a({ href => "./?cmd=search&query=$query&fq=type:$_" }, $_ );
			$types_facet .= '  &nbsp;&nbsp;' . $cgi->img({ src => "./etc/$_.png" }) . " $link (" . $types{ $_ } . ')' . $cgi->br;
			
		}
		if ( ! $types_facet ) { $types_facet = " &nbsp;&nbsp;<span style='color: silver'>(none)</span>" }
	
		# repository facet
		my %repositories       = &get_facets( $response->facet_counts->{ facet_fields }->{ repository } );
		my $repositories_facet = '';
		foreach ( sort( keys( %repositories ))) {
		
			my $link = $cgi->a({ href => "./?$params&fq=repository:" . '"' . $_ . '"' }, $_ );
			my $repository_icon = '';
			if ( $_ =~ /Alex/ or $_ =~ /Gallery/ ) { $repository_icon = $cgi->img({ src => "./etc/infomotions.ico", width => "16", height => "16" }) }
			if ( $_ =~ /DOAJ/ ) { $repository_icon = $cgi->img({ src => "./etc/doaj.png", width => "16", height => "16" }) }
			if ( $_ =~ /Gutenberg/ ) { $repository_icon = $cgi->img({ src => "./etc/gutenberg.ico", width => "16", height => "16" }) }
			if ( $_ =~ /Hathi/ ) { $repository_icon = $cgi->img({ src => "./etc/hathi.png", width => "16", height => "16" }) }
			if ( $_ =~ /Archive/ ) { $repository_icon = $cgi->img({ src => "./etc/archive.ico", width => "16", height => "16" }) }
			$repositories_facet .= " &nbsp;&nbsp;$repository_icon $link (" . $repositories{ $_ } . ')' . $cgi->br;
			
		}
		if ( ! $repositories_facet ) { $repositories_facet = " &nbsp;&nbsp;<span style='color: silver'>(none)</span>" }

		# subjects facet
		my %subjects       = &get_facets( $response->facet_counts->{ facet_fields }->{ facet_subject } );
		my $subjects_facet = '';
		my $subject_count = 0;
		foreach ( sort { $subjects{ $b } <=> $subjects{ $a } } keys( %subjects )) {
		
			next if ( ! $_ );
			my $link = $cgi->a({ href => "./?$params&fq=facet_subject:" . '"' . $_ . '"' }, $_ );
			$subject_count++;
			if ( $subject_count == 5 ) { $subjects_facet .= " <a href=\"javascript:expand('subjects')\" style=\"color: grey; text-decoration: none\">more...</a><span id='subjects' style=\"display: none\">" }
			$subjects_facet .= "$link&nbsp;(" . $subjects{ $_ } . ") ";
			
		}
		if ( $subject_count > 4 ) { $subjects_facet .= '</span>' }
		if ( ! $subjects_facet ) { $subjects_facet = "<span style='color: silver'>(none)</span>" }
	
		# creators facet
		my %creators       = &get_facets( $response->facet_counts->{ facet_fields }->{ facet_creator } );
		my $creators_facet = '';
		my $creator_count = 0;
		foreach ( sort { $creators{ $b } <=> $creators{ $a } } keys( %creators )) {
		
			next if ( ! $_ );
			my $link = $cgi->a({ href => "./?$params&fq=facet_creator:" . '"' . $_ . '"' }, $_ );
			$creator_count++;
			if ( $creator_count == 5 ) { $creators_facet .= " <a href=\"javascript:expand('authors')\" style=\"color: grey; text-decoration: none\">more...</a><span id='authors' style=\"display: none\">" }
			$creators_facet .= "$link&nbsp;(" . $creators{ $_ } . ") ";
			
		}
		if ( $creator_count > 4 ) { $creators_facet .= '</span>' }
		if ( ! $creators_facet ) { $creators_facet = "<span style='color: silver'>(none)</span>" }
	
		# build the hitlist
		my @hits       = $response->docs;
		my $hit_count  = $response->content->{ response }->{ numFound };
		my $hitlist    = '';
		my $highlights = $response->content->{ highlighting };
		foreach my $doc ( @hits ) {
		
			# slurp
			my $id          = $doc->value_for( 'id' );
			my $title       = $doc->value_for( 'title' );
			my $publisher   = $doc->value_for( 'publisher' );
			my $creator     = $doc->value_for( 'creator' );
			#my $creator     = ''; foreach ( @creator ) { $creator .= "$_; " }
			my $contributor = $doc->value_for( 'contributor' );
			my $url         = $doc->value_for( 'url' );
			my @subjects    = $doc->values_for('subject' );
			my $subject     = ''; foreach ( @subjects ) { $subject .= "$_; " }
			my $source      = $doc->value_for( 'source' );
			my $description = $doc->value_for( 'description' );
			my $format      = $doc->value_for( 'format' );
			my $type        = $doc->value_for( 'type' );
			my $relation    = $doc->value_for( 'relation' );
			my $repository  = $doc->value_for( 'repository' );
			my $snippet     =  $highlights->{ $id }->{ fulltext }->[ 0 ];
			   $snippet    .=  ' ... ' . $highlights->{ $id }->{ fulltext }->[ 1 ];
			   $snippet     =~ s{\s+}{ }g;
			
			# details
			my $sublist = '';
			if ( $creator ) { $sublist .= $cgi->li( "<b>creator(s)</b> - $creator" ) }
			if ( $contributor ) { $sublist .= $cgi->li( "<b>contributor</b> - $contributor" ) }
			if ( $url ) { $sublist .= $cgi->li( "<b>links</b> - " . $cgi->a({ href => $url}, 'view document' )) }
			if ( $description ) { $sublist .= $cgi->li( "<b>description</b> - $description" ) }
			if ( $format ) { $sublist .= $cgi->li( "<b>format</b> - $format" ) }
			if ( $publisher ) { $sublist .= $cgi->li( "<b>publisher</b> - $publisher" ) }
			if ( $relation ) {
				if ( $relation =~ /^http:/ ) { $sublist .= $cgi->li( "<b>relation</b> - " . $cgi->a({ href => $relation }, 'local cache' ))}
				else { $sublist .= $cgi->li( "<b>relation</b> - $relation" )}
			}
			if ( $source ) {
				if ( $source =~ /^http:/ or $source =~ /^gopher:/ ) { $sublist .= $cgi->li( "<b>source</b> - " . $cgi->a({ href => $source }, 'original file' ))}
				else { $sublist .= $cgi->li( "<b>source: </b>$source" )}
			}
			if ( $subject ) { $sublist .= $cgi->li( "<b>subject(s)</b> - $subject" )}
			if ( $title ) { $sublist .= $cgi->li( "<b>title</b> - $title" )}
			if ( $type ) { $sublist .= $cgi->li( "<b>type</b> - $type" )}
			$sublist = $cgi->ul( {style => 'margin-bottom: 1em'}, $sublist );
			$sublist = $cgi->div({ -id => $id, -style => 'display: none' }, $sublist );
	
			# cute icons
			my $type_icon = $cgi->img({ src => "./etc/$type.png" });
			my $repository_icon = '';
			if ( $repository =~ /Alex/ or $repository =~ /Gallery/ ) { $repository_icon = $cgi->img({ src => "./etc/infomotions.ico", width => "16", height => "16" }) }
			if ( $repository =~ /DOAJ/ ) { $repository_icon = $cgi->img({ src => "./etc/doaj.png", width => "16", height => "16" }) }
			if ( $repository =~ /Gutenberg/ ) { $repository_icon = $cgi->img({ src => "./etc/gutenberg.ico", width => "16", height => "16" }) }
			if ( $repository =~ /Hathi/ ) { $repository_icon = $cgi->img({ src => "./etc/hathi.png", width => "16", height => "16" }) }
			if ( $repository =~ /Archive/ ) { $repository_icon = $cgi->img({ src => "./etc/archive.ico", width => "16", height => "16" }) }
			
			# hit list
			my $main_entry = $title;
			if ( $creator ) { $main_entry .= " / $creator" }
			
			
			#$hitlist .= $cgi->li({ style => 'margin-bottom: 1em' }, $type_icon . ' ' . $repository_icon . ' &nbsp;' . $cgi->a({ href => $url, style => 'font-size: large' }, $main_entry ) . $cgi->br . $snippet . ' &nbsp;' . $cgi->a( { -href => "javascript:expand('$id')", -style => 'color: grey; text-decoration: none' }, 'details...' ) . $sublist );	
			$hitlist .= $cgi->li({ style => 'margin-bottom: 1em' }, $cgi->a({ href => $url, style => 'font-size: large' }, $main_entry ) . $cgi->br . $snippet . ' &nbsp;' . $cgi->a( { -href => "javascript:expand('$id')", -style => 'color: grey; text-decoration: none' }, 'details...' ) . $sublist );	
			
		}
		$hitlist = $cgi->ol( { start => ( $start + 1 )}, $hitlist );
		
		my $query_suggestions = &suggest_queries( $cgi->param( 'query' ), $cgi );
		my $synonyms = &suggest_synonyms( $cgi->param( 'query' ), $cgi );
		
		
		# add filter query
		my $fq = '';
		if ( $cgi->param( 'fq' )) {
		
			foreach ( $cgi->param( 'fq' )) { $fq .= "&fq=$_" }
			
		};

		# sorts
		my $aaz = "./?cmd=search&query=$query&sort=sort_creator%20asc,sort_title%20asc$fq";
		my $aza = "./?cmd=search&query=$query&sort=sort_creator%20desc,sort_title%20asc";
		my $taz = "./?cmd=search&query=$query&sort=sort_title%20asc,sort_creator%20asc$fq";
		my $tza = "./?cmd=search&query=$query&sort=sort_title%20desc,sort_creator%20asc$fq";
		my $rnk = "./?cmd=search&query=$query$fq";
		
		# display the results page and quit
		$html .= &slurp( TEMPLATE );
		$html =~ s/##CONTENT##/&slurp( RESULTS )/e;
		$html =~ s/##FORM##/&slurp( FORM )/ge;
		$html =~ s/##FORMSMALL##//ge;
		$html =~ s/##QUERY##/$cgi->param( 'query' )/ge;
		$html =~ s/##NUMBEROFHITS##/&commify( $hit_count )/ge;
		$html =~ s/##HITLIST##/$hitlist/ge;
		$html =~ s/##TYPES##/$types_facet/ge;
		$html =~ s/##CREATORS##/$creators_facet/ge;
		$html =~ s/##SUBJECTS##/$subjects_facet/ge;
		$html =~ s/##REPOSITORIES##/$repositories_facet/ge;
		$html =~ s/##PAGER##/&pager( '?cmd=search&query=' . $cgi->param( 'query' ) . "&sort=$sort". '&start=', $start, $hit_count, $cgi )/e;
		$html =~ s/##QUERYSUGGESTIONS##/$query_suggestions/e;
		$html =~ s/##SYNONYMS##/$synonyms/e;
		$html =~ s/##AAZ##/$aaz/e;
		$html =~ s/##AZA##/$aza/e;
		$html =~ s/##TAZ##/$taz/e;
		$html =~ s/##TZA##/$tza/e;
		$html =~ s/##RNK##/$rnk/e;
	
	}

	# done
	$r->content_type( 'text/html' );
	$r->print( "$html" );
	return Apache2::Const::OK;

}


sub pager {

	# get the input
	my $link  = shift;
	my $start = shift;
	my $size  = shift;
	my $cgi   = shift;
	
	# create the links
	my $previous = $cgi->a({ -href => $link . ( $start - ROWS ) }, 'Previous' ) . '&#xA0;&#xA0;';
	my $next     = '&#xA0;&#xA0;' . $cgi->a({ -href => $link . ( $start + ROWS ) }, 'Next' );
	
	# build the pager
	my $pager;
	if ( $start - ROWS >= 0 ) { $pager = $previous }
	if ( $start + ROWS < $size ) { $pager .= $next }
	
	# done
	return $pager;

}

=cut
sub enhance_query {

	my $query = shift;
	while ( $query =~ /^ / ) { $query =~ s/^ // }
	while ( $query =~ / $/ ) { $query =~ s/ $// }
	while ( $query =~ /  / ) { $query =~ s/  / / }
	$query =~ s/=/:/g;
	$query =~ s/'/"/g;
	$query =~ s/ and / AND /g;
	$query =~ s/ or / OR /g;
	$query =~ s/ not / NOT /g;
	
	if ($query =~ /\s/) {
	
		if (( $query =~ / AND / ) | ( $query =~ / OR / ) | ($ query =~ / NOT / )) { }
		elsif ( $query =~ /:/ ) { }
		elsif ( $query !~ /"/ ) {
		
			# try to make queries with no syntactical sugar a bit "smarter"
			my @terms = split / /, $query;
			my $enhancement = '';
			for (my $i; $i <= $#terms; $i++) {
			
				if ($i < $#terms) { $enhancement .= $terms[ $i ] . ' AND ' }
				else { $enhancement .= $terms[ $i ] }
			
			}
			$query = '"' . $query . '"' . " OR ($enhancement)";
			
		}
		
	}
	
	return $query;

}
=cut

sub suggest_queries {

	my $query = shift;
	my $cgi   = shift;
	
	# normalize the query
	$query =~ s/ =/=/g;
	$query =~ s/= /=/g;
	while ( $query =~ /  / ) { $query =~ s/  / / }

	my $suggestions;
	if ( $query !~ / / && $query !~ /=/ ) {
	
		$suggestions  = ' &nbsp;&nbsp;' . $cgi->a({ href => './?cmd=search&query=subject=' . $query }, 'Subject tags' ) . $cgi->br;
		$suggestions .= ' &nbsp;&nbsp;' . $cgi->a({ href => './?cmd=search&query=creator='  . $query }, 'Author names'  ) . $cgi->br;
		$suggestions .= ' &nbsp;&nbsp;' . $cgi->a({ href => './?cmd=search&query=title='   . $query }, 'Title words'   ) . $cgi->br;
	
	}
	
	elsif ( $query !~ / / && $query =~ /creator/ ) {
	
		$query =~ s/creator=//;
		$suggestions  = ' &nbsp;&nbsp;' . $cgi->a({ href => './?cmd=search&query=subject=' . $query }, 'Subject tags' ) . $cgi->br;
		$suggestions .= ' &nbsp;&nbsp;' . $cgi->a({ href => './?cmd=search&query=title='   . $query }, 'Title words'   ) . $cgi->br;
	
	}
	
	elsif ( $query !~ / / && $query =~ /title/ ) {
	
		$query =~ s/title=//;
		$suggestions  = ' &nbsp;&nbsp;' . $cgi->a({ href => './?cmd=search&query=subject=' . $query }, 'Subject tags' ) . $cgi->br;
		$suggestions .= ' &nbsp;&nbsp;' . $cgi->a({ href => './?cmd=search&query=creator='  . $query }, 'Author names'   ) . $cgi->br;
	
	}
	
	elsif ( $query !~ / / && $query =~ /subject/ ) {
	
		$query =~ s/subject=//;
		$suggestions  = ' &nbsp;&nbsp;' . $cgi->a({ href => './?cmd=search&query=creator=' . $query }, 'Author names' ) . $cgi->br;
		$suggestions .= ' &nbsp;&nbsp;' . $cgi->a({ href => './?cmd=search&query=title='  . $query }, 'Title words'   ) . '<br />';
	
	}
	
	elsif ( $query =~ / / && $query =~ /=/ ) {
	
		my @words = &tokenize_query( $cgi->param( 'query' ));
		my $field_search;
		if ( $cgi->param( 'query' ) =~ /subject/ ) {
		
			foreach ( @words ) {
			
				next if ( $_ eq 'AND' or $_ eq 'OR' or $_ eq 'NOT' );;
				$field_search .= "creator=$_ AND ";	
		
			}
			$field_search =~ s/ AND $//;
			$suggestions  .= ' &nbsp;&nbsp;' . $cgi->a({ href => "./?cmd=search&query=$field_search"}, 'Author names' ) . $cgi->br;
					
			$field_search = '';
			foreach ( @words ) {
			
				next if ( $_ eq 'AND' or $_ eq 'OR' or $_ eq 'NOT' );;
				$field_search .= "title=$_ AND ";	
		
			}
			$field_search =~ s/ AND $//;
			$suggestions  .= ' &nbsp;&nbsp;' . $cgi->a({ href => "./?cmd=search&query=$field_search"}, 'Title words' ) . $cgi->br;
					
		}
			
		if ( $cgi->param( 'query' ) =~ /creator/ ) {
		
			foreach ( @words ) {
			
				next if ( $_ eq 'AND' or $_ eq 'OR' or $_ eq 'NOT' );;
				$field_search .= "subject=$_ AND ";	
		
			}
			$field_search =~ s/ AND $//;
			$suggestions  .= ' &nbsp;&nbsp;' . $cgi->a({ href => "./?cmd=search&query=$field_search"}, 'Subject tags' ) . $cgi->br;
					
			$field_search = '';
			foreach ( @words ) {
			
				next if ( $_ eq 'AND' or $_ eq 'OR' or $_ eq 'NOT' );;
				$field_search .= "title=$_ AND ";	
		
			}
			$field_search =~ s/ AND $//;
			$suggestions  .= ' &nbsp;&nbsp;' . $cgi->a({ href => "./?cmd=search&query=$field_search"}, 'Title words' ) . $cgi->br;
					
		}
			
		if ( $cgi->param( 'query' ) =~ /title/ ) {
		
			foreach ( @words ) {
			
				next if ( $_ eq 'AND' or $_ eq 'OR' or $_ eq 'NOT' );;
				$field_search .= "subject=$_ AND ";	
		
			}
			$field_search =~ s/ AND $//;
			$suggestions  .= ' &nbsp;&nbsp;' . $cgi->a({ href => "./?cmd=search&query=$field_search"}, 'Subject tags' ) . $cgi->br;
					
			$field_search = '';
			foreach ( @words ) {
			
				next if ( $_ eq 'AND' or $_ eq 'OR' or $_ eq 'NOT' );;
				$field_search .= "creator=$_ AND ";	
		
			}
			$field_search =~ s/ AND $//;
			$suggestions  .= ' &nbsp;&nbsp;' . $cgi->a({ href => "./?cmd=search&query=$field_search"}, 'Author name' ) . $cgi->br;
					
		}
			
	}
	
	elsif ( $query =~ / / && $query !~ /=/ ) {
	
		# further normalization
		$query =~ s/"//g;
		$query =~ s/'//g;
		while ( $query =~ /  / ) { $query =~ s/  / / }
		
		# get each query term
		my @terms = split / /, $query;
		
		# build subject search
		my $field_search = '';
		foreach ( @terms ) {
		
			next if ( $_ eq 'AND' or $_ eq 'OR' or $_ eq 'NOT' );;
			$field_search .= "subject=$_ AND ";	
		
		}
		$field_search =~ s/ AND $//;
		$suggestions  .= ' &nbsp;&nbsp;' . $cgi->a({ href => "./?cmd=search&query=$field_search"}, 'Subject tags' ) . $cgi->br;

		# author search
		$field_search = '';
		foreach ( @terms ) {
		
			next if ( $_ eq 'AND' or $_ eq 'OR' or $_ eq 'NOT' );;
			$field_search .= "creator=$_ AND ";	
		
		}
		$field_search =~ s/ AND $//;
		$suggestions  .= ' &nbsp;&nbsp;' . $cgi->a({ href => "./?cmd=search&query=$field_search"}, 'Author names' ) . $cgi->br;

		# title search
		$field_search = '';
		foreach ( @terms ) {
		
			next if ( $_ eq 'AND' or $_ eq 'OR' or $_ eq 'NOT' );;
			$field_search .= "title=$_ AND ";	
		
		}
		$field_search =~ s/ AND $//;
		$suggestions  .= ' &nbsp;&nbsp;' . $cgi->a({ href => "./?cmd=search&query=$field_search"}, 'Title words' ) . $cgi->br;

	}
	
	# done
	return $suggestions;

}


sub tokenize_query {

	my $words = shift;
	
	# clean it
	$words =~ s/=//g;
	$words =~ s/title//g;
	$words =~ s/creator//g;
	$words =~ s/subject//g;
	$words =~ s/\*//g;
	$words =~ s/'//g;
	$words =~ s/"//g;
	$words =~ s/"//g;
	while ( $words =~ /  / ) { $words =~ s/  / / }
	
	# return an array of words
	return split / /, $words;

}

sub suggest_synonyms {

	my @words = &tokenize_query( shift );
	my $cgi   = shift;

	# initialize
	my @synonyms = ();
	my %seen     = ();
	
	my $wn = new Lingua::Wordnet;
	foreach my $word ( @words ) {
	
		foreach my $pos ( POSES ) {
		
			my @synsets = $wn->lookup_synset( $word, $pos );
			foreach my $synset (@synsets) {
			
				foreach  ( $synset->words ) {
				
					s/\%\d+$//;
					s/\_/ /g;
					push ( @synonyms, $_ ) unless $seen{ $_ }++;
				
				}
			
			}
			
		}

	}
	
	@synonyms = sort @synonyms;
	my $list = '';
	foreach ( @synonyms ) {
	
		if ( $_ =~ / / ) { $list .= $cgi->a({ href => qq|./?cmd=search&query="$_"| }, $_ ) . '; ' }
		else { $list .= $cgi->a({ href => "./?cmd=search&query=$_" }, $_ ) . '; ' }
		
	}
	
	$list =~ s/; $//;
	if ( ! $list ) { $list = "<span style='color: silver'>(none)</span>" }
	return $list;
	
}


sub commify {

	# commify a number. Perl Cookbook, 2.17, p. 64
	my $text = reverse $_[0];
	$text =~ s/(\d\d\d)(?=\d)(?!\d*\.)/$1,/g;
	return scalar reverse $text;
}


# return true or die
1;