#!/bin/env perl

print "==== Example 6 - RDQL query / bound variable results\n" ;
print "==== Get the titles of the books\n" ;

require Joseki ;
require Joseki::ResultSet ;
require RDF::Core::Model ;
require RDF::Core::Resource ;
require RDF::Core::Literal ;
require RDF::Core::Model::Serializer ;

my $kbURL = 'http://jena.hpl.hp.com:2020/books' ;
if ( $#ARGV != -1 )
{
    $kbURL = shift ;
    print "Data source = $kbURL\n" ;
}

my $rdql = 
    'SELECT ?book, ?title WHERE '.
    '(?book dc:title ?title)'.
    'USING dc FOR <http://purl.org/dc/elements/1.1/>' ;

# Use the underlying classes, not the convenience wrapper functions,
# and add the format argument to control the presentation/

# Either will do
$BV="http://jena.hpl.hp.com/2003/07/query/BV" ;
#$BV="BV" ;

my $request = new Joseki::Request($kbURL, 'RDQL',
				  query=>$rdql, format=>$BV ) ;
my $response =$request->execute() ;
$response->is_success || die "Request to $r$kbURL failed\n" ;

## print $response->content ;
## print "\n" ;

my $m = $response->model() ;

## Read locally
## require RDF::Core::Model::Parser ;
## 
## my $storage = new RDF::Core::Storage::Memory;
## my $m = new RDF::Core::Model(Storage => $storage) ;
## my $parser = new RDF::Core::Model::Parser(Model => $m ,
## 					  Source=>'data.rdf', 
## 					  SourceType=>'file',
## 					  BaseURI=>'urn:unknown#');
## $parser->parse ;



## ## Write put model.
## my $xml = '' ;
## my $serializer = new RDF::Core::Model::Serializer(Model=>$m,
## 						  Output=>\$xml,
## 						  BaseURI => 'URI://BASE/'
## 						  );
# Fails to indent the XML - why?
## $serializer->serialize;
## print "$xml\n";
## 

# Print result set

my $rs = new Joseki::ResultSet($m) ;
$rs->iter ;

for (  ; $rs->hasNext ; )
{
    my $rb = $rs->next ;

    my $book = $rb->get('book') ;
    my $title = $rb->get('title')->getValue ;

    print $book->getURI,"  has title\n" ;
    print "    '$title'\n" ;

##     for $var ($rb->vars())
##     {
## 	my $val = $rb->get($var) ;
## 	print '  ' ;
## 	print "$var = " ;
## 	print $val->getLabel ; 
## 	print "\n" ;	
##     }
}



## 
## printModelStmts($m) ;
## 
## sub printModelStmts
## {
##     my($model) = @_ ;
##     my $sIter = $model->getStmts;
##     my $stmt = $sIter->getFirst; 
##     for(; defined $stmt ; $stmt = $sIter->getNext )
##     {
## 	print "[ ",$stmt->getSubject->getURI,
##               ",\n      ",$stmt->getPredicate->getURI,
##               ",\n      ",$stmt->getObject->getLabel," ]\n" ;
## 	
##     }
##     $sIter->close ;
## }