Web components

<?php
/**
 * @file PageTransform.class.php
 * Definition of PageTransform class.
 * @author Kamil Dudka <xdudka00@gmail.com>
 */
 
class PageTransform {
  public static function buildIfNeeded($target, $xslt, $xml = 'index.xml') {
    $obj = new self($target, $xslt, $xml);
    if ($obj->needUpdate())
      $obj->buildTarget();
  }
  // Avoid class instantiation
  private function __construct($target, $xslt, $xml) {
    $config = Config::instance();
    $this->pageDir_ = $config->documentRoot().$config->pageDir();
    $this->target_ = $target;
    $this->xslt_ = $xslt;
    $this->xml_ = $xml;
  }
  private $pageDir_;
  private $target_;
  private $xslt_;
  private $xml_;
  private function needUpdate() {
    if (!file_exists($this->target_))
      return true;
 
    $ts = filemtime($this->target_);
    if (filemtime($this->pageDir_)>$ts)
      return true;
    $fileList = scandir($this->pageDir_);
    array_shift($fileList);
    array_shift($fileList);
    foreach($fileList as $current)
      if (filemtime($this->pageDir_.'/'.$current)>$ts)
        return true;
    return false;
  }
  private function buildTarget() {
    // Load the XML source
    $xml = new DOMDocument;
    $xml->load($this->pageDir_.'/'.$this->xml_);
    $xsl = new DOMDocument;
    $xsl->load($this->pageDir_.'/'.$this->xslt_);
 
    // Configure the transformer
    $proc = new XSLTProcessor;
    $proc->importStyleSheet($xsl); // attach the xsl rules
 
    // Process XSLT and write to $this->target_
    $fd = fopen($this->target_, 'w');
    fwrite($fd, $proc->transformToXML($xml));
    fclose($fd);
  }
};
?>