stylesheet.cls.php

来自「国外很不错的一个开源OA系统Group-Office」· PHP 代码 · 共 875 行 · 第 1/2 页

        
        switch ( $tok{$j} ) {

        case "~":
        case "|":
          $op .= $tok{$j++};

          if ( $tok{$j} != "=" )
            throw new DOMPDF_Exception("Invalid CSS selector syntax: invalid attribute selector: $selector");

          $op .= $tok{$j};
          break;

        case "=":
          $op = "=";
          break;

        }
       
        // Read the attribute value, if required
        if ( $op != "" ) {
          $j++;
          while ( $j < $tok_len ) {
            if ( $tok{$j} == "]" )
              break;
            $value .= $tok{$j++};
          }            
        }
       
        if ( $attr == "" )
          throw new DOMPDF_Exception("Invalid CSS selector syntax: missing attribute name");

        switch ( $op ) {

        case "":
          $query .=  "[@$attr]";
          break;
         
        case "=":
          $query .= "[@$attr$op\"$value\"]";
          break;

        case "~=":
          // FIXME: this will break if $value contains quoted strings
          // (e.g. [type~="a b c" "d e f"])
          $values = explode(" ", $value);
          $query .=  "[";

          foreach ( $values as $val ) 
            $query .= "@$attr=\"$val\" or ";
         
          $query = rtrim($query, " or ") . "]";
          break;

        case "|=":
          $values = explode("-", $value);
          $query .= "[";

          foreach ($values as $val)
            $query .= "starts-with(@$attr, \"$val\") or ";

          $query = rtrim($query, " or ") . "]";
          break;
         
        }
     
        break;
      }
    }
    $i++;
      
//       case ":":
//         // Pseudo selectors: ignore for now.  Partially handled directly
//         // below.

//         // Skip until the next special character, leaving the token as-is
//         while ( $i < $len ) {
//           if ( in_array($selector{$i}, $delimiters) )
//             break;
//           $i++;
//         }
//         break;
        
//       default:
//         // Add the character to the token
//         $tok .= $selector{$i++};
//         break;
//       }

//    }
    
    
    // Trim the trailing '/' from the query
    if ( mb_strlen($query) > 2 )
      $query = rtrim($query, "/");
    
    return $query;
  }

  /**
   * applies all current styles to a particular document tree
   *
   * apply_styles() applies all currently loaded styles to the provided
   * {@link Frame_Tree}.  Aside from parsing CSS, this is the main purpose
   * of this class.
   *
   * @param Frame_Tree $tree
   */
  function apply_styles(Frame_Tree $tree) {

    // Use XPath to select nodes.  This would be easier if we could attach
    // Frame objects directly to DOMNodes using the setUserData() method, but
    // we can't do that just yet.  Instead, we set a _node attribute_ in 
    // Frame->set_id() and use that as a handle on the Frame object via
    // Frame_Tree::$_registry.

    // We create a scratch array of styles indexed by frame id.  Once all
    // styles have been assigned, we order the cached styles by specificity
    // and create a final style object to assign to the frame.

    // FIXME: this is not particularly robust...    

    $styles = array();
    $xp = new DOMXPath($tree->get_dom());

    // Apply all styles in stylesheet
    foreach ($this->_styles as $selector => $style) {

      $query = $this->_css_selector_to_xpath($selector);
//       pre_var_dump($selector);
//       pre_var_dump($query);
//        echo ($style);
      
      // Retrieve the nodes      
      $nodes = $xp->query($query);

      foreach ($nodes as $node) {
        //echo $node->nodeName . "\n";
        // Retrieve the node id
        if ( $node->nodeType != 1 ) // Only DOMElements get styles
          continue;
        
        $id = $node->getAttribute("frame_id");

        // Assign the current style to the scratch array
        $spec = $this->_specificity($selector);
        $styles[$id][$spec][] = $style;
      }
    }

    // Now create the styles and assign them to the appropriate frames.  (We
    // iterate over the tree using an implicit Frame_Tree iterator.)
    $root_flg = false;
    foreach ($tree->get_frames() as $frame) {
      // pre_r($frame->get_node()->nodeName . ":");
            
      if ( !$root_flg && $this->_page_style ) {
        $style = $this->_page_style;
        $root_flg = true;

      } else 
        $style = $this->create_style();

      // Find nearest DOMElement parent
      $p = $frame;      
      while ( $p = $p->get_parent() )
        if ($p->get_node()->nodeType == 1 )
          break;
      
      // Styles can only be applied directly to DOMElements; anonymous
      // frames inherit from their parent
      if ( $frame->get_node()->nodeType != 1 ) {
        if ( $p )
          $style->inherit($p->get_style());
        $frame->set_style($style);
        continue;
      }

      $id = $frame->get_id();

      // Handle HTML 4.0 attributes
      Attribute_Translator::translate_attributes($frame);
    
      // Locate any additional style attributes      
      if ( ($str = $frame->get_node()->getAttribute("style")) !== "" ) {
        $spec = $this->_specificity("!style attribute");
        $styles[$id][$spec][] = $this->_parse_properties($str);
      }
      
      // Grab the applicable styles
      if ( isset($styles[$id]) ) {
        
        $applied_styles = $styles[ $frame->get_id() ];

        // Sort by specificity
        ksort($applied_styles);

        // Merge the new styles with the inherited styles
        foreach ($applied_styles as $arr) {
          foreach ($arr as $s) 
            $style->merge($s);
        }
      }

      // Inherit parent's styles if required
      if ( $p ) {
        $style->inherit( $p->get_style() );
      }

//       pre_r($frame->get_node()->nodeName . ":");
//      echo "<pre>";
//      echo $style;
//      echo "</pre>";
      $frame->set_style($style);
      
    }
    
    // We're done!  Clean out the registry of all styles since we
    // won't be needing this later.
    foreach ( array_keys($this->_styles) as $key ) {
      unset($this->_styles[$key]);
    }
    
  }
  

  /**
   * parse a CSS string using a regex parser
   *
   * Called by {@link Stylesheet::parse_css()} 
   *
   * @param string $str 
   */
  private function _parse_css($str) {

    // Destroy comments
    $css = preg_replace("'/\*.*?\*/'si", "", $str);

    // FIXME: handle '{' within strings, e.g. [attr="string {}"]

    // Something more legible:
    $re =
      "/\s*                                   # Skip leading whitespace                             \n".
      "( @([^\s]+)\s+([^{;]*) (?:;|({)) )?    # Match @rules followed by ';' or '{'                 \n".
      "(?(1)                                  # Only parse sub-sections if we're in an @rule...     \n".
      "  (?(4)                                # ...and if there was a leading '{'                   \n".
      "    \s*( (?:(?>[^{}]+) ({)?            # Parse rulesets and individual @page rules           \n".
      "            (?(6) (?>[^}]*) }) \s*)+?  \n".
      "       )                               \n".
      "   })                                  # Balancing '}'                                \n".
      "|                                      # Branch to match regular rules (not preceeded by '@')\n".
      "([^{]*{[^}]*}))                        # Parse normal rulesets\n".
      "/xs";
     
    if ( preg_match_all($re, $css, $matches, PREG_SET_ORDER) === false )
      // An error occured
      throw new DOMPDF_Exception("Error parsing css file: preg_match_all() failed.");

    // After matching, the array indicies are set as follows:
    //
    // [0] => complete text of match
    // [1] => contains '@import ...;' or '@media {' if applicable
    // [2] => text following @ for cases where [1] is set
    // [3] => media types or full text following '@import ...;'
    // [4] => '{', if present
    // [5] => rulesets within media rules
    // [6] => '{', within media rules
    // [7] => individual rules, outside of media rules
    //
    //pre_r($matches);
    foreach ( $matches as $match ) {
      $match[2] = trim($match[2]);

      if ( $match[2] !== "" ) {
        // Handle @rules
        switch ($match[2]) {

        case "import":          
          $this->_parse_import($match[3]);
          break;

        case "media":
          if ( in_array(mb_strtolower(trim($match[3])), self::$ACCEPTED_MEDIA_TYPES ) ) {
            $this->_parse_sections($match[5]);
          }
          break;

        case "page":
          // Store the style for later...
          if ( is_null($this->_page_style) )
            $this->_page_style = $this->_parse_properties($match[5]);
          else
            $this->_page_style->merge($this->_parse_properties($match[5]));
          break;
          
        default:
          // ignore everything else
          break;
        }

        continue;
      }

      if ( $match[7] !== "" ) 
        $this->_parse_sections($match[7]);
      
    }
  }

  
  /**
   * parse @import{} sections
   *
   * @param string $url  the url of the imported CSS file
   */
  private function _parse_import($url) {
    $arr = preg_split("/[\s\n]/", $url);
    $url = array_pop($arr);
    $accept = false;
    
    if ( count($arr) > 0 ) {
      
      // @import url media_type [media_type...]
      foreach ( $arr as $type ) {
        if ( in_array($type, self::$ACCEPTED_MEDIA_TYPES) ) {
          $accept = true;
          break;
        }
      }
      
    } else
      // unconditional import
      $accept = true;
    
    if ( $accept ) {
      $url = str_replace(array('"',"url", "(", ")"), "", $url);
      // Store our current base url properties in case the new url is elsewhere
      $protocol = $this->_protocol;
      $host = $this->_base_host;
      $path = $this->_base_path;

      // If the protocol is php, assume that we will import using file://
      $url = build_url($protocol == "php://" ? "file://" : $protocol, $host, $path, $url);
      
      $this->load_css_file($url);
      
      // Restore the current base url
      $this->_protocol = $protocol;
      $this->_base_host = $host;
      $this->_base_path = $path;
    }
    
  }

  /**
   * parse regular CSS blocks
   *
   * _parse_properties() creates a new Style object based on the provided
   * CSS rules.
   *
   * @param string $str  CSS rules
   * @return Style
   */
  private function _parse_properties($str) {
    $properties = explode(";", $str);

    // Create the style
    $style = new Style($this);
    foreach ($properties as $prop) {

      $prop = trim($prop);

      if ($prop == "")
        continue;

      $i = mb_strpos($prop, ":");
      if ( $i === false )
        continue;

      $prop_name = mb_strtolower(mb_substr($prop, 0, $i));
      $value = mb_substr($prop, $i+1);
      $style->$prop_name = $value;

    }

    return $style;
  }

  /**
   * parse selector + rulesets
   *
   * @param string $str  CSS selectors and rulesets
   */
  private function _parse_sections($str) {
    // Pre-process: collapse all whitespace and strip whitespace around '>',
    // '.', ':', '+', '#'
    
    $patterns = array("/[\\s\n]+/", "/\\s+([>.:+#])\\s+/");
    $replacements = array(" ", "\\1");
    $str = preg_replace($patterns, $replacements, $str);

    $sections = explode("}", $str);
    foreach ($sections as $sect) {
      $i = mb_strpos($sect, "{");

      $selectors = explode(",", mb_substr($sect, 0, $i));
      $style = $this->_parse_properties(trim(mb_substr($sect, $i+1)));

      // Assign it to the selected elements
      foreach ($selectors as $selector) {
        $selector = trim($selector);
        
        if ($selector == "")
          continue;
        
        $this->add_style($selector, $style);
      }
    }
  }  

  /**
   * dumps the entire stylesheet as a string
   *
   * Generates a string of each selector and associated style in the
   * Stylesheet.  Useful for debugging.
   *
   * @return string
   */
  function __toString() {
    $str = "";
    foreach ($this->_styles as $selector => $style) 
      $str .= "$selector => " . $style->__toString() . "\n";

    return $str;
  }
}