// $Id: nice_menus.js,v 1.1.2.2 2006/08/06 10:16:20 jakeg Exp $

// We only do the javascript in IE.

var csshoverReg = /(^|\s)(([^a]([^ ]+)?)|(a([^#.][^ ]+)+)):(hover|active)/i,
currentSheet, doc = window.document, hoverEvents = [], activators = {
  onhover:{on:'onmouseover', off:'onmouseout'},
  onactive:{on:'onmousedown', off:'onmouseup'}
}

function parseStylesheets() {
  if(!/MSIE (5|6)/.test(navigator.userAgent)) return;
  window.attachEvent('onunload', unhookHoverEvents);
  var sheets = doc.styleSheets, l = sheets.length;
  for(var i=0; i<l; i++) 
    parseStylesheet(sheets[i]);
}
  function parseStylesheet(sheet) {
    if(sheet.imports) {
      try {
        var imports = sheet.imports, l = imports.length;
        for(var i=0; i<l; i++) parseStylesheet(sheet.imports[i]);
      } catch(securityException){}
    }

    try {
      var rules = (currentSheet = sheet).rules, l = rules.length;
      for(var j=0; j<l; j++) parseCSSRule(rules[j]);
    } catch(securityException){}
  }

  function parseCSSRule(rule) {
    var select = rule.selectorText, style = rule.style.cssText;
    if(!csshoverReg.test(select) || !style) return;

    var pseudo = select.replace(/[^:]+:([a-z-]+).*/i, 'on$1');
    var newSelect = select.replace(/(\.([a-z0-9_-]+):[a-z]+)|(:[a-z]+)/gi, '.$2' + pseudo);
    var className = (/\.([a-z0-9_-]*on(hover|active))/i).exec(newSelect)[1];
    var affected = select.replace(/:(hover|active).*$/, '');
    var elements = getElementsBySelect(affected);
    if(elements.length == 0) return;

    currentSheet.addRule(newSelect, style);
    for(var i=0; i<elements.length; i++)
      new HoverElement(elements[i], className, activators[pseudo]);
  }

function HoverElement(node, className, events) {
  if(!node.hovers) node.hovers = {};
  if(node.hovers[className]) return;
  node.hovers[className] = true;
  hookHoverEvent(node, events.on, function() { node.className += ' ' + className; });
  hookHoverEvent(node, events.off, function() { node.className = node.className.replace(new RegExp('\\s+'+className, 'g'),''); });
}
  function hookHoverEvent(node, type, handler) {
    node.attachEvent(type, handler);
    hoverEvents[hoverEvents.length] = { 
      node:node, type:type, handler:handler 
    };
  }

  function unhookHoverEvents() {
    for(var e,i=0; i<hoverEvents.length; i++) {
      e = hoverEvents[i]; 
      e.node.detachEvent(e.type, e.handler);
    }
  }

function getElementsBySelect(rule) {
  var parts, nodes = [doc];
  parts = rule.split(' ');
  for(var i=0; i<parts.length; i++) {
    nodes = getSelectedNodes(parts[i], nodes);
  } return nodes;
}
  function getSelectedNodes(select, elements) {
    var result, node, nodes = [];
    var identify = (/\#([a-z0-9_-]+)/i).exec(select);
    if(identify) {
      var element = doc.getElementById(identify[1]);
      return element? [element]:nodes;
    }
    
    var classname = (/\.([a-z0-9_-]+)/i).exec(select);
    var tagName = select.replace(/(\.|\#|\:)[a-z0-9_-]+/i, '');
    var classReg = classname? new RegExp('\\b' + classname[1] + '\\b'):false;
    for(var i=0; i<elements.length; i++) {
      result = tagName? elements[i].all.tags(tagName):elements[i].all; 
      for(var j=0; j<result.length; j++) {
        node = result[j];
        if(classReg && !classReg.test(node.className)) continue;
        nodes[nodes.length] = node;
      }
    } 
    
    return nodes;
  }
  // This is the Drupal method of adding a function to the BODY onload event.  (See misc/drupal.js)