Custom URL handling about lessphp HOT 1 OPEN

I found a way to do this in a derived class with an ugly hack. Here's my currently functional code.

  // extension for import to use theme URLs
  function import(&$url, &$media)
  {
    $ret = parent::import($url, $media);
    if ($ret)
    {
      $url = $this->processURL($url);
    }
    return $ret;
  }

  function lib_url($arg)
  {
    return 'url('.$this->processURL($this->compileValue($arg), true).')';
  }
  
  function processURL($url, $relative = false)
  {
    // nasty hack, because processURL entirely replaces the functionality
    // that $this->importDir was previously used for. We look to see if there
    // was a value for $this->importDir, and if so, we move it to a new variable
    // $this->baseUrlDir. Then we clear $this->importDir so that it doesn't get
    // in the way later.
    if ($this->importDir)
    {
      $this->baseUrlDir = $this->importDir;
      $this->importDir = null;
    }

    // remove quotes, if present
    if ($this->quoted($url)) $url = substr($url, 1, -1);
    
    // find the protocol, if any
    $protocol = '';
    if (preg_match('~^([a-zA-Z]+)\:[\\/]?[\\/]?(.*)~', $url, $matches))
    {
      // this URL has a protocol
      $protocol = isset($matches[1]) ? $matches[1] : '';
      $path = isset($matches[2]) ? $matches[2] : '';
      
      // TODO: do we need to do anything special with any protocols?
      switch ($protocol)
      {
      // the following cases should always return the input directly. We don't need to do anything special.
      case 'data':
      case 'http':
      case 'https':
      default:
        return $url; // return the original URL
      }
    }
    else
    {
      // No protocol. This is a relative URL of some sort.
      
      // normalize slashes
      $url = str_replace('\\', '/', $url);
      $docroot = str_replace('\\', '/', $_SERVER['DOCUMENT_ROOT']);
      $base = str_replace('\\', '/', $this->baseUrlDir);
      
      // if the url starts with a slash, it is an absolute path from the document root
      if ($url{0} == '/')
      {
        return $url;
      }
      else // just a normal relative path
      {
        // convert to an absolute path
        $url = rtrim($base, '/').'/'.ltrim($url, '/');
        
        if ($relative)
        {
          // a relative path is wanted, so reduce it to a path from the document root
          $url = str_replace($docroot, '', $url);
          if ($url{0} != '/')
          {
            $url = '/'.$url;
          }
        }
        
        return $url;
      }
    }
    
    return $url;
  }

With some small tweaks to the above I can add support for hierarchical themed URLs. This also shows how the processing can address some issues with images, so that the final file always contains the proper full path to the image (fixes some issues with importing files from another directory for example).

from lessphp.