
<?
    # A PHP/XSLT based transformer and browser for
    # Friend-of-a-Friend (FoaF) descriptions.
    #
    # (c) 2002-2006 Morten Frederiksen
    #
    # XSS bug fixes by Robby Griffin.
    #
    # License: http://www.gnu.org/licenses/gpl
    #
    if ($_SERVER['REMOTE_ADDR']=='192.168.1.16')
        error_reporting(2047);
    header('Connection: close');
    if (preg_match('|inktomisearch.com$|',@$_SERVER['REMOTE_HOST'])
            || preg_match('|betaspider.com$|',@$_SERVER['REMOTE_HOST'])) {
        header('HTTP/1.1 403 Slow Down');
        exit;
    }

    include_once('../getFoaF.php');
    $Redland=librdf_php_get_world();

    $metadata='explorer.rdf';
    $foaf='http://www.mfd-consult.dk/index.rdf';
    $ifp='foaf-ifp.xsl';
    $xsl='explorer.xsl';
#if (preg_match('|^192\.168\.|',$_SERVER['REMOTE_ADDR']))
#    $xsl='explorer-1.11.xsl';

    if (@$_GET['foaf']!='')
        $foaf=$_GET['foaf'];

    $xslt=xslt_create();
    xslt_set_error_handler($xslt,'xsltError');
    $xslterror='';

    if (preg_match('|^wn:([a-z])([a-z_]+)$|i',$foaf,$M))
        $foaf='http://xmlns.com/wordnet/1.6/'.strtoupper($M[1]).strtolower($M[2]);
    list($foaf,$foafdata)=getFoaF($foaf);
#if (preg_match('|^192\.168\.|',$_SERVER['REMOTE_ADDR']))
#    print($foafdata);

    $xhtml='';
    if ($foafdata && @$_GET['source']=='foaf')
        $xhtml='<pre>'.htmlspecialchars($foafdata).'</pre>';
    elseif ($foafdata)
    {
        $foafIFP=@xslt_process($xslt,'arg:/_xml','arg:/_xsl',NULL,
                array('/_xsl'=>join('',file($ifp)),'/_xml'=>$foafdata),
                array('foaf'=>$foaf));
        $foafdata=redlandify($foaf,$foafdata);
        $NS='<?xml version="1.0" encoding="UTF-8"?><ns>';
        if (preg_match_all('|xmlns(:[^=\s]+)?\s*=\s*[\'"]([^\'"]+)[\'"]|',$foafdata,$M,PREG_SET_ORDER))
        {
            $uris=array();
            foreach ($M as $ns)
            {
                $uri=$ns[2];
                $uris[$uri]=1;
            };
            foreach (array_keys($uris) as $uri)
            {
                if (!preg_match('|^http:|',$uri))
                    break;
                $file='ns/'.preg_replace('|[^a-z0-9\.-]|','',$uri);
                if (file_exists($file) &&
                        (filesize($file)<=1 && filemtime($file)>(time()-30*86400)
                        || filemtime($file)>(time()-30*86400)))
                    $schema=join('',file($file));
                else
                {
                    $rdf='<?xml version="1.0"?>
<xsl:stylesheet
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    version="1.0">
<xsl:output
    method="xml"
    omit-xml-declaration="yes"
    encoding="utf-8"/>
<xsl:template match="/">
    <xsl:copy-of select="//rdf:RDF"/>
</xsl:template>
</xsl:stylesheet>';
                    $rdfs=getFoaF_curl($uri);
                    if (!($schema=@xslt_process($xslt,'arg:/_xml','arg:/_xsl',NULL,
                            array('/_xsl'=>$rdf,'/_xml'=>$rdfs))))
                    {
                        $rdfs=preg_replace('|^.+?(<\w+:RDF.+</\w+:RDF>).+$|s','$1',$rdfs);
                        $schema=@xslt_process($xslt,'arg:/_xml','arg:/_xsl',NULL,
                                array('/_xsl'=>$rdf,'/_xml'=>$rdfs));
                    };
                    if (strlen($schema)==1)
                        $schema='';
                    if ($fp=fopen($file,'w'))
                    {
                        @fwrite($fp,$schema);
                        !@fclose($fp);
                    };
                };
                $NS.='<schema ns="'.$uri.'">';
                $NS.=$schema.'</schema>';
            };
        };
        $NS.='</ns>';
        if ($foafdata=='!')
        {
            $xhtml='<head><title>Error</title></head>
<body><h1>Error</h1><p>Unable to parse FoaF (<a href="'.htmlspecialchars($foaf).'">'.htmlspecialchars($foaf).'</a>).</p><p>It doesn\'t seem to be valid RDF/XML, you may want to try out the <a href="http://www.w3.org/RDF/Validator/">RDF Validator</a>.</p></body>';
        }
        elseif (($xhtml=xslt_process($xslt,'arg:/_xml','arg:/_xsl',NULL,
                array('/_xsl'=>join('',@file($xsl)),'/_xml'=>$foafdata,
                '/schema'=>$NS,'/ifp'=>$foafIFP),
                array('foaf'=>$foaf,'ifp'=>'1','schema'=>'1')))
                && ($xhtml!='<?xml version="1.0" encoding="UTF-8"?>'."\n"))
        {
            $metafoot=xslt_process($xslt,'arg:/_xml','arg:/_xsl',NULL,
                    array('/_xsl'=>join('',@file('metafoot.xsl',1)),'/_xml'=>join('',file($metadata))));
            print(str_replace('<!--foaf-explorer-footer-->',$metafoot,$xhtml));
            exit;
        }
        else
            $xhtml='<head><title>Error</title></head>
<body><h1>Error</h1><p>Unable to parse FoaF (<a href="'.htmlspecialchars($foaf).'">'.htmlspecialchars($foaf).'</a>).</p><p>It doesn\'t seem to be valid RDF/XML, you may want to try out the <a href="http://www.w3.org/RDF/Validator/">RDF Validator</a>.</p><p>Raw XSLT error message: '.$xslterror.'</p></body>';
    }
    else
        $xhtml='<head><title>Error</title></head>
<body><h1>Error</h1><p>Unable to find or read FoaF (<a href="'.htmlspecialchars($foaf).'">'.htmlspecialchars($foaf).'</a>).</p><pre>'.($foafdata?htmlspecialchars($foafdata):'').'</pre></body>';

    if ($xhtml!='')
    {
        $xhtml='<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
'.$xhtml.'</html>';
        print($xhtml);
    };

    function xsltError($x,$e,$l,$f)
    {
        global $xslterror;
        $xslterror='Sablotron XSLT transformation error';
        reset($f);
        while(list($key,$val)=each($f))
        {
            if ($key=='line')
                $xslterror.=' on line '.$val;
            if ($key=='msg')
                $xslterror.=': <strong>'.$val.'</strong>';
        };
        $xslterror.='.';
    };

    function redlandify($uri,$rdfxml)
    {
        global $Redland;

        /* Parse... */
        $base=librdf_new_uri($Redland,$uri);
        $parser=librdf_new_parser($Redland,'raptor','application/rdf+xml',librdf_new_uri($Redland,'-'));
        $stream=librdf_parser_parse_string_as_stream($parser,$rdfxml,$base);
        if (!$stream || librdf_stream_end($stream))
            return '!';
        $Nodes=array();
        $Namespaces=array('http://www.w3.org/1999/02/22-rdf-syntax-ns#'=>'rdf');
        $count=0;
        while (!librdf_stream_end($stream))
        {
            $statement=librdf_stream_get_object($stream);
            $subject=librdf_new_node_from_node(librdf_statement_get_subject($statement));
            $predicate=librdf_new_node_from_node(librdf_statement_get_predicate($statement));
            $object=librdf_new_node_from_node(librdf_statement_get_object($statement));
            $preduri=librdf_uri_to_string(librdf_node_get_uri($predicate));
            if (preg_match('|^(\w+:.+#)(.+)$|',$preduri,$Predicate)
                    || preg_match('|^(\w+:.+\?)(.+)$|',$preduri,$Predicate)
                    || preg_match('|^(\w+:.+/)([^/]+)$|',$preduri,$Predicate))
            {
                if (!key_exists($Predicate[1],$Namespaces))
                    $Namespaces[$Predicate[1]]='ns'.count($Namespaces);
                $predicate=$Namespaces[$Predicate[1]].':'.$Predicate[2];
                $node=librdf_node_to_string($subject);
                if (!key_exists($node,$Nodes))
                    $Nodes[$node]=array();
                $found=0;
                $os=librdf_node_to_string($object);
                reset($Nodes[$node]);
                while(!$found && list(,$pso)=each($Nodes[$node])) {
                    $p=key($pso);
                    list($s,$o)=current($pso);
                    $found=($p==$predicate && librdf_node_to_string($o)==$os);
                }
                if(!$found)
                    array_push($Nodes[$node],array($predicate=>array($subject,$object)));
            }
            librdf_stream_next($stream);
            $count++;
        };
        librdf_free_stream($stream);
        librdf_free_parser($parser);
        librdf_free_uri($base);
        $stream=0;
        $parser=0;
        $base=0;
        if ($count>2500 && !preg_match('|^192\.168\.|',$_SERVER['REMOTE_ADDR'])) {
            header('HTTP/1.1 400 Bad Request');
            header('Content-Type: text/plain');
            print("ETOOMANYTRIPLES: Sorry, that URI contains too many triples ($count), unable to transform.");
            exit;
        }

        /* Reserialize... */
        $xml='<?xml version="1.0" encoding="UTF-8"?><rdf:RDF';
        while (list($uri,$prefix)=each($Namespaces))
            $xml.="\n  xmlns:$prefix=\"$uri\"";
        $xml.=">\n";
        reset($Nodes);
        while (list(,$Node)=each($Nodes))
        {
            reset($Node);
            $pso=current($Node);
            $p=key($pso);
            list($s,$o)=current($pso);
            $xml.='<rdf:Description';
            if (librdf_node_get_type($s)==1)
            {
                $uriref=librdf_node_get_uri($s);
                $xml.=' rdf:about="'.htmlspecialchars(librdf_uri_to_string($uriref)).'"';
            }
            else
            {
                $name=librdf_node_get_blank_identifier($s);
#                $xml.=' rdf:nodeID="'.htmlspecialchars($name).'"';
                $xml.=' rdf:ID="'.htmlspecialchars($name).'"';
            }
            $xml.=">\n";
            $lastn='';
            while (list(,$pso)=each($Node))
            {
                $predicate=key($pso);
                list(,$object)=current($pso);
                $n='  <'.$predicate;
                $type=librdf_node_get_type($object);
                if ($type==1)
                    $n.=' rdf:resource="'.htmlspecialchars(librdf_uri_to_string(librdf_node_get_uri($object))).'"/';
                elseif ($type==4)
#                    $xml.=' rdf:nodeID="'.htmlspecialchars(librdf_node_get_blank_identifier($object)).'"/';
                    $n.=' rdf:resource="#'.htmlspecialchars(librdf_node_get_blank_identifier($object)).'"/';
                elseif ($type==2)
                {
                    if (librdf_node_get_literal_value_language($object)!='')
                        $n.=' xml:lang="'.htmlspecialchars(librdf_node_get_literal_value_language($object)).'"';
#                    if (librdf_node_get_literal_value_datatype_uri($object))
#                        $xml.=' rdf:datatype="'.htmlspecialchars(librdf_uri_to_string(librdf_node_get_literal_value_datatype_uri($object))).'"';
                    if (librdf_node_get_literal_value_is_wf_xml($object))
                        $n.=' rdf:parseType="Literal">'.librdf_node_get_literal_value($object).'</'.$predicate;
                    else
                        $n.='>'.htmlspecialchars(librdf_node_get_literal_value($object)).'</'.$predicate;
                }
                $n.=">\n";
                if($n!=$lastn)
                    $xml.=$n;
                $lastn=$n;
            };
            $xml.="</rdf:Description>\n";
        };
        $xml.="</rdf:RDF>";
#if ($_SERVER['REMOTE_ADDR']=='192.168.1.16')
#    print($xml);
        return $xml;
    };

#librdf_uri* error_count_uri=librdf_new_uri(world, LIBRDF_PARSER_FEATURE_ERROR_COUNT);
#const char* error_count_string=librdf_parser_get_feature(parser, error_count_uri);
#int error_count=atoi(error_count_string);
#fprintf(stderr, "Parsing returned %d errors\n", error_count);
#librdf_free_uri(error_count_uri)

?>