/v1/mod_semanticweb/arc/extractors/ARC2_RDFExtractor.php

<?php

/*

homepage: http://arc.semsol.org/

license:  http://arc.semsol.org/license



class:    ARC2 RDF Extractor

author:   Benjamin Nowack

version:  2008-11-18 (Fix: Skip comments. Thanks to Masahide Kanzaki)

*/



ARC2::inc('Class');



class ARC2_RDFExtractor extends ARC2_Class {



  function __construct($a = '', &$caller) {

    parent::__construct($a, $caller);

  }

  

  function ARC2_RDFExtractor($a = '', &$caller) {

    $this->__construct($a, $caller);

  }



  function __init() {

    parent::__init();

    $this->nodes = $this->caller->getNodes();

    $this->index = $this->caller->getNodeIndex();

    $this->bnode_prefix = $this->v('bnode_prefix', 'arc' . substr(md5(uniqid(rand())), 0, 4) . 'b', $this->a);

    $this->bnode_id = 0;

    $this->keep_cdata_ws = $this->v('keep_cdata_whitespace', 0, $this->a);

    if (!isset($this->a['ns'])) $this->a['ns'] = array('rdf' => 'http://www.w3.org/1999/02/22-rdf-syntax-ns#');

  }



  /*  */

  

  function x($re, $v, $options = 'si') {

    return ARC2::x($re, $v, $options);

  }



  function camelCase($v) {

    $r = ucfirst($v);

    while (preg_match('/^(.*)[\-\_ ](.*)$/', $r, $m)) {

      $r = $m[1] . ucfirst($m[2]);

    }

    return $r;

  }



  function createBnodeID(){

    $this->bnode_id++;

    return '_:' . $this->bnode_prefix . $this->bnode_id;

  }



  /*  */

  

  function extractRDF() {

  }



  /*  */

  

  function addTs($ts) {

    foreach ($ts as $t) {

      $this->caller->addT($t);

    }

  }

  

  function addT($t) {

    return $this->caller->addT($t);

  }

  

  /*  */

  

  function getSubNodes($n) {

    return $this->v($n['id'], array(), $this->index);

  }

  

  function getParentNode($n) {

    return isset($this->nodes[$n['p_id']]) ? $this->nodes[$n['p_id']] : 0;

  }



  /*  */

  

  function getSubNodesByClass($n, $cls, $skip_self = 0) {

    if (!$skip_self && $this->hasClass($n, $cls)) {

      return array($n);

    }

    $r = array();

    $sns = $this->getSubNodes($n);

    foreach ($sns as $sn) {

      if ($sub_r = $this->getSubNodesByClass($sn, $cls, 0)) {

        $r = array_merge($r, $sub_r);

      }

    }

    return $r;

  }

  

  function getSubNodeByClass($n, $cls, $skip_self = 0) {

    if (!$skip_self && $this->hasClass($n, $cls)) {

      return $n;

    }

    $sns = $this->getSubNodes($n);

    foreach ($sns as $sn) {

      if ($sub_r = $this->getSubNodeByClass($sn, $cls, 0)) {

        return $sub_r;

      }

    }

    return 0;

  }

  

  function getParentNodeByClass($n, $cls, $skip_self = 0) {

    if (!$skip_self && $this->hasClass($n, $cls)) {

      return $n;

    }

    if ($pn = $this->getParentNode($n)) {

      if ($sub_r = $this->getParentNodeByClass($pn, $cls, 0)) {

        return $sub_r;

      }

    }

    return 0;

  }

  

  /*  */

  

  function hasAttribute($a, $n, $v) {

    $vs = is_array($v) ? $v : array($v);

    $a_vs = $this->v($a . ' m', array(), $n['a']);

    return array_intersect($vs, $a_vs) ? 1 : 0;

  }

  

  function hasClass($n, $v) {

    return $this->hasAttribute('class', $n, $v);

  }



  function hasRel($n, $v) {

    return $this->hasAttribute('rel', $n, $v);

  }



  /*  */



  function getDocBase() {

    $root_node = $this->getRootNode();

    $r = $root_node['doc_base'];

    foreach ($this->getSubNodes($root_node) as $root_child) {

      if ($root_child['tag'] == 'head') {

        foreach ($this->getSubNodes($root_child) as $head_child) {

          if ($head_child['tag'] == 'base') {

            $r = $head_child['a']['href'];

            break;

          }

        }

      }

    }

    return $r;

  }

  

  /*  */

  

  function getPlainContent($n, $trim = 1) {

    if ($n['tag'] == 'comment') {

      $r = '';

    }

    elseif ($n['tag'] == 'cdata') {

      $r = $n['a']['value'];

    }

    elseif (trim($this->v('cdata', '', $n))) {

      $r = $n['cdata'];

      $sub_nodes = $this->getSubNodes($n);

      foreach ($sub_nodes as $sub_n) {

        $r .= $this->getPlainContent($sub_n, 0);

      }

    }

    elseif (($n['tag'] == 'img') && isset($n['a']['alt'])) {

      $r = $n['a']['alt'];

    }

    else {

      $r = '';

      $sub_nodes = $this->getSubNodes($n);

      foreach ($sub_nodes as $sub_n) {

        $r .= $this->getPlainContent($sub_n, 0);

      }

    }

    $r = preg_replace('/\s/s', ' ', $r);

    $r = preg_replace('/\s\s*/s', ' ', $r);

    return $trim ? trim($r) : $r;

  }

  

  function getContent($n, $outer = 0, $trim = 1) {

    //echo '<pre>' . htmlspecialchars(print_r($n, 1)) . '</pre>';

    if ($n['tag'] == 'comment') {

      $r = '<!-- ' . $n['a']['value'] . ' -->';

    }

    elseif ($n['tag'] == 'cdata') {

      $r = $n['a']['value'];

    }

    else {

      $r = '';

      if ($outer) {

        $r .= '<' . $n['tag'];

        asort($n['a']);

        if (isset($n['a']['xmlns']) && $n['a']['xmlns']['']) {

          $r .= ' xmlns="' . $n['a']['xmlns'][''] . '"';

        }

        foreach ($n['a'] as $a => $val) {

          if (!is_array($val) && isset($n['a'][$a . ' uri'])) $val = $n['a'][$a . ' uri'];

          $r .= preg_match('/^[^\s]+$/', $a) && !is_array($val) ? ' ' . $a . '="' . addslashes($val) . '"' : '';

        }

        $r .= $n['empty'] ? '/>' : '>';

      }

      if (!$n['empty']) {

        $r .= $this->v('cdata', '', $n);

        $sub_nodes = $this->getSubNodes($n);

        foreach ($sub_nodes as $sub_n) {

          $r .= $this->getContent($sub_n, 1, 0);

        }

        if ($outer) {

          $r .= '</' . $n['tag'] . '>';

        }

      }

    }

    return ($trim && !$this->keep_cdata_ws) ? trim($r) : $r;

  }

  

  /*  */

  

  function getDocID($n) {

    $id = $n['id'];

    $k = 'doc_' . $id;

    if (!isset($this->caller->cache[$k])) {

      $this->caller->cache[$k] = $n['doc_url'];

    }

    return $this->caller->cache[$k];

  }



  function getDocOwnerID($n) {

    return '_:owner_of_' . $this->normalize($this->getDocID($n));

  }

  

  /*  */



  function normalize($v) {

    $v = preg_replace('/[\W\s]+/is', '_', strip_tags(strtolower($v)));

    $v = preg_replace('/http/', '', $v);

    $v = preg_replace('/[\_]+/', '_', $v);

    //$v = substr($v, 0, 30);

    $v = trim($v, '_');

    return $v;

  }



  /*  */

  

}