builder.js

// Copyright (c) 2005-2008 Thomas Fuchs (http://script.aculo.us, http://mir.aculo.us)
//
// script.aculo.us is freely distributable under the terms of an MIT-style license.
// For details, see the script.aculo.us web site: http://script.aculo.us/

var Builder = {
  NODEMAP: {
    AREA: 'map',
    CAPTION: 'table',
    COL: 'table',
    COLGROUP: 'table',
    LEGEND: 'fieldset',
    OPTGROUP: 'select',
    OPTION: 'select',
    PARAM: 'object',
    TBODY: 'table',
    TD: 'table',
    TFOOT: 'table',
    TH: 'table',
    THEAD: 'table',
    TR: 'table'
  },
  // note: For Firefox < 1.5, OPTION and OPTGROUP tags are currently broken,
  //       due to a Firefox bug
  node: function(elementName) {
    elementName = elementName.toUpperCase();
    
    // try innerHTML approach
    var parentTag = this.NODEMAP[elementName] || 'div';
    var parentElement = document.createElement(parentTag);
    try { // prevent IE "feature": http://dev.rubyonrails.org/ticket/2707
      parentElement.innerHTML = "<" + elementName + "></" + elementName + ">";
    } catch(e) {}
    var element = parentElement.firstChild || null;
      
    // see if browser added wrapping tags
    if(element && (element.tagName.toUpperCase() != elementName))
      element = element.getElementsByTagName(elementName)[0];
    
    // fallback to createElement approach
    if(!element) element = document.createElement(elementName);
    
    // abort if nothing could be created
    if(!element) return;

    // attributes (or text)
    if(arguments[1])
      if(this._isStringOrNumber(arguments[1]) ||
        (arguments[1] instanceof Array) ||
        arguments[1].tagName) {
          this._children(element, arguments[1]);
        } else {
          var attrs = this._attributes(arguments[1]);
          if(attrs.length) {
            try { // prevent IE "feature": http://dev.rubyonrails.org/ticket/2707
              parentElement.innerHTML = "<" +elementName + " " +
                attrs + "></" + elementName + ">";
            } catch(e) {}
            element = parentElement.firstChild || null;
            // workaround firefox 1.0.X bug
            if(!element) {
              element = document.createElement(elementName);
              for(attr in arguments[1]) 
                element[attr == 'class' ? 'className' : attr] = arguments[1][attr];
            }
            if(element.tagName.toUpperCase() != elementName)
              element = parentElement.getElementsByTagName(elementName)[0];
          }
        } 

    // text, or array of children
    if(arguments[2])
      this._children(element, arguments[2]);

     return $(element);
  },
  _text: function(text) {
     return document.createTextNode(text);
  },

  ATTR_MAP: {
    'className': 'class',
    'htmlFor': 'for'
  },

  _attributes: function(attributes) {
    var attrs = [];
    for(attribute in attributes)
      attrs.push((attribute in this.ATTR_MAP ? this.ATTR_MAP[attribute] : attribute) +
          '="' + attributes[attribute].toString().escapeHTML().gsub(/"/,'&quot;') + '"');
    return attrs.join(" ");
  },
  _children: function(element, children) {
    if(children.tagName) {
      element.appendChild(children);
      return;
    }
    if(typeof children=='object') { // array can hold nodes and text
      children.flatten().each( function(e) {
        if(typeof e=='object')
          element.appendChild(e);
        else
          if(Builder._isStringOrNumber(e))
            element.appendChild(Builder._text(e));
      });
    } else
      if(Builder._isStringOrNumber(children))
        element.appendChild(Builder._text(children));
  },
  _isStringOrNumber: function(param) {
    return(typeof param=='string' || typeof param=='number');
  },
  build: function(html) {
    var element = this.node('div');
    $(element).update(html.strip());
    return element.down();
  },
  dump: function(scope) { 
    if(typeof scope != 'object' && typeof scope != 'function') scope = window; //global scope 
  
    var tags = ("A ABBR ACRONYM ADDRESS APPLET AREA B BASE BASEFONT BDO BIG BLOCKQUOTE BODY " +
      "BR BUTTON CAPTION CENTER CITE CODE COL COLGROUP DD DEL DFN DIR DIV DL DT EM FIELDSET " +
      "FONT FORM FRAME FRAMESET H1 H2 H3 H4 H5 H6 HEAD HR HTML I IFRAME IMG INPUT INS ISINDEX "+
      "KBD LABEL LEGEND LI LINK MAP MENU META NOFRAMES NOSCRIPT OBJECT OL OPTGROUP OPTION P "+
      "PARAM PRE Q S SAMP SCRIPT SELECT SMALL SPAN STRIKE STRONG STYLE SUB SUP TABLE TBODY TD "+
      "TEXTAREA TFOOT TH THEAD TITLE TR TT U UL VAR").split(/\s+/);
  
    tags.each( function(tag){ 
      scope[tag] = function() { 
        return Builder.node.apply(Builder, [tag].concat($A(arguments)));  
      };
    });
  }
};