<?
/*
    This work is in the public domain:
    SEE: http://creativecommons.org/licenses/publicdomain/
*/
    function XMLParser($data_source, $data_source_type='raw', $collapse_dups=0, $index_numeric=0) {
        $data = '';
        if ($data_source_type == 'raw')
            $data = $data_source;

        elseif ($data_source_type == 'stream') {
            while (!feof($data_source))
                $data .= fread($data_source, 1000);

        // try filename, then if that fails...
        } elseif (file_exists($data_source))
            $data = implode('', file($data_source));

        // try url
        else {
            $fp = fopen($data_source,'r');
            while (!feof($fp))
                $data .= fread($fp, 1000);
            fclose($fp);
        }
    return $data;
    }

    // Parse the XML file into a verbose, flat array struct.
    // Then, coerce that into a simple nested array.
    function getTree($data) {
        $parser = xml_parser_create('ISO-8859-1');
        xml_parser_set_option($parser, XML_OPTION_SKIP_WHITE, 1);
        xml_parse_into_struct($parser, $data, $vals, $index);
        xml_parser_free($parser);

        $i = -1;
        return getchildren($vals, $i);
    }

    // internal function: build a node of the tree
    function buildtag($thisvals, $vals, &$i, $type) {

        if (isset($thisvals['attributes']))
            $tag['ATTRIBUTES'] = $thisvals['attributes'];

        // complete tag, just return it for storage in array
        if ($type === 'complete')
            $tag['VALUE'] = $thisvals['value'];

        // open tag, recurse
        else
            $tag = array_merge($tag, getchildren($vals, $i));

        return $tag;
    }

    // internal function: build an nested array representing children
    function getchildren($vals, &$i) {
        $children = array();     // Contains node data

        // Node has CDATA before it's children
                if ($i > -1 && isset($vals[$i]['value']))
            $children['VALUE'] = $vals[$i]['value'];

        // Loop through children, until hit close tag or run out of tags
        while (++$i < count($vals)) {

            $type = $vals[$i]['type'];

            // 'cdata':    Node has CDATA after one of it's children
            //         (Add to cdata found before in this case)
            if ($type === 'cdata')
                $children['VALUE'] .= $vals[$i]['value'];

            // 'complete':    At end of current branch
            // 'open':    Node has children, recurse
            elseif ($type === 'complete' || $type === 'open') {
                $tag = buildtag($vals[$i], $vals, $i, $type);
                if ($index_numeric) {
                    $tag['TAG'] = $vals[$i]['tag'];
                    $children[] = $tag;
                } else
                    $children[$vals[$i]['tag']][] = $tag;
            }

            // 'close:    End of node, return collected data
            //        Do not increment $i or nodes disappear!
            elseif ($type === 'close')
                break;
        }
        if ($collapse_dups)
            foreach($children as $key => $value)
                if (is_array($value) && (count($value) == 1))
                    $children[$key] = $value[0];
        return $children;
    }

#http://dannyayers.com/misc/foaf/rel3.rdf
#http://www.brain-stream.com/xml/foaf.rdf
# http://rdfweb.org/people/danbri/rdfweb/danbri-foaf.rdf

  $parser = XMLParser('http://www.wasab.dk/morten/blog/archives/author/mortenf/foaf.rdf', 'url', 0);#schema/rdf-schema
 
  $tree = getTree($parser);

  $personName = $tree['RDF:RDF'][0]['FOAF:PERSON'][0]['FOAF:NAME'][0]['VALUE'];
  $personNick = $tree['RDF:RDF'][0]['FOAF:PERSON'][0]['FOAF:NICK'][0]['VALUE']; 
  $personSha1 = $tree['RDF:RDF'][0]['FOAF:PERSON'][0]['FOAF:MBOX_SHA1SUM'][0]['VALUE'];
  $personHomePage = $tree['RDF:RDF'][0]['FOAF:PERSON'][0]['FOAF:HOMEPAGE'][0]['ATTRIBUTES']['RDF:RESOURCE'];
  $personImage = $tree['RDF:RDF'][0]['FOAF:PERSON'][0]['FOAF:DEPICTION'][0]['ATTRIBUTES']['RDF:RESOURCE'];

  while(list($key,$val)=each($tree['RDF:RDF'][0]['FOAF:PERSON'][0]['FOAF:KNOWS'])){
    $knows[$key]['personName'] = $val['FOAF:PERSON'][0]['FOAF:NAME'][0]['VALUE'];
    $knows[$key]['personSha1'] = $val['FOAF:PERSON'][0]['FOAF:MBOX_SHA1SUM'][0]['VALUE'];
  }

  #print_r($tree['RDF:RDF'][0]['FOAF:PERSON'][0]['FOAF:KNOWS']);
  echo "<a href='parse.phps'>source</a><br>";
  echo "<pre>";
  echo "personName = $personName\n";
  echo "personNick = $personNick\n";
  echo "personSha1 = $personSha1\n";
  echo "personHomePage = $personHomePage\n";
  echo "personImage = $personImage\n";
  echo "<br><b>KNOWS ARRAY</b>\n";
  print_r($knows);
  echo "<br><b>based on</b>";
  print_r($tree);
  #$test = implode(":", $tree);
  #print_r($test);
/*
  function combiner($arr){
    while(list($key,$val)=each($arr)){
        if(is_array($val)){
            $ret .= combiner($val);
        }else{
            $ret .= $key."^".$val." ";
        }
    }
    return $ret;
  }
  reset($tree); 
  while(list($key,$val)=each($tree['RDF:RDF'][0])){
      echo combiner($val)."<br>\n";
  }
*/
?>