/*
   Behaviour v1.1 by Ben Nolan, June 2005. Based largely on the work
   of Simon Willison (see comments by Simon below).

   Description:
   	
   	Uses css selectors to apply javascript behaviours to enable
   	unobtrusive javascript in html documents.
   	
   Usage:   
   
	var myrules = {
		'b.someclass' : function(element){
			element.onclick = function(){
				alert(this.innerHTML);
			}
		},
		'#someid u' : function(element){
			element.onmouseover = function(){
				this.innerHTML = "BLAH!";
			}
		}
	};
	
	Behaviour.register(myrules);
	
	// Call Behaviour.apply() to re-apply the rules (if you
	// update the dom, etc).

   License:
   
   	This file is entirely BSD licensed.
   	
   More information:
   	
   	http://ripcord.co.nz/behaviour/
   
*/   

var Behaviour = 
{
	list : new Array,

	register : function(sheet)
	{
		Behaviour.list.push(sheet);
	},

	start : function()
	{
		Behaviour.addLoadEvent(function()
		{
			Behaviour.apply();
		});
	},

	apply : function()
	{
		for (h = 0; sheet = Behaviour.list[h]; h++)
		{
			for (selector in sheet)
			{
				list = document.getElementsBySelector(selector);
				if (!list) {continue;}
				for (i = 0; element = list[i]; i++){sheet[selector](element);}
			}
		}
	},

	addLoadEvent : function(func)
	{
		var oldonload = window.onload;

		if (typeof window.onload != 'function')
		{
			window.onload = func;
		}
		else
		{
			window.onload = function()
			{
				oldonload();
				func();
			}
		}
	}
}

Behaviour.start();

/*
   The following code is Copyright (C) Simon Willison 2004.

   document.getElementsBySelector(selector)
   - returns an array of element objects from the current document
     matching the CSS selector. Selectors can contain element names, 
     class names and ids and can be nested. For example:
     
       elements = document.getElementsBySelect('div#main p a.external')
     
     Will return an array of all 'a' elements with 'external' in their 
     class attribute that are contained inside 'p' elements that are 
     contained inside the 'div' element which has id="main"

   New in version 0.4: Support for CSS2 and CSS3 attribute selectors:
   See http://www.w3.org/TR/css3-selectors/#attribute-selectors

   Version 0.4 - Simon Willison, March 25th 2003
   -- Works in Phoenix 0.5, Mozilla 1.3, Opera 7, Internet Explorer 6, Internet Explorer 5 on Windows
   -- Opera 7 fails 
*/

function getAllChildren(e)
{
	// Returns all children of element. Workaround required for IE5/Windows. Ugh.
	return e.all ? e.all : e.getElementsByTagName('*');
}

document.getElementsBySelector = function(selector)
{
	// Attempt to fail gracefully in lesser browsers
	if (!document.getElementsByTagName)
	{
		return new Array();
	}

	// Split selector in to tokens
	var tokens = selector.split(' ');
	var currentContext = new Array(document);
	for (var i = 0; i < tokens.length; i++)
	{
		token = tokens[i].replace(/^\s+/,'').replace(/\s+$/,'');;
		if (token.indexOf('#') > -1)
		{
			// Token is an ID selector
			var bits = token.split('#');
			var tagName = bits[0];
			var id = bits[1];
			var element = document.getElementById(id);
			if (tagName && element.nodeName.toLowerCase() != tagName)
			{
				// tag with that ID not found, return false
				return new Array();
			}
			// Set currentContext to contain just this element
			currentContext = new Array(element);
			continue; // Skip to next token
		}

		if (token.indexOf('.') > -1)
		{
			// Token contains a class selector
			var bits = token.split('.');
			var tagName = bits[0];
			var className = bits[1];
			if (!tagName)
			{
				tagName = '*';
			}

			// Get elements matching tag, filter them for class selector
			var found = new Array;
			var foundCount = 0;
			for (var h = 0; h < currentContext.length; h++)
			{
				var elements;
				if (tagName == '*')
				{
					elements = getAllChildren(currentContext[h]);
				}
				else
				{
					elements = currentContext[h].getElementsByTagName(tagName);
				}

				for (var j = 0; j < elements.length; j++)
				{
					found[foundCount++] = elements[j];
				}
			}

			currentContext = new Array;
			var currentContextIndex = 0;
			for (var k = 0; k < found.length; k++)
			{
				if (found[k].className && found[k].className.match(new RegExp('\\b'+className+'\\b')))
				{
					currentContext[currentContextIndex++] = found[k];
				}
			}

			continue; // Skip to next token
		}

		// Code to deal with attribute selectors
		if (token.match(/^(\w*)\[(\w+)([=~\|\^\$\*]?)=?"?([^\]"]*)"?\]$/))
		{
			var tagName = RegExp.$1;
			var attrName = RegExp.$2;
			var attrOperator = RegExp.$3;
			var attrValue = RegExp.$4;
			if (!tagName)
			{
				tagName = '*';
			}

			// Grab all of the tagName elements within current context
			var found = new Array;
			var foundCount = 0;
			for (var h = 0; h < currentContext.length; h++)
			{
				var elements;
				if (tagName == '*')
				{
					elements = getAllChildren(currentContext[h]);
				}
				else
				{
					elements = currentContext[h].getElementsByTagName(tagName);
				}

				for (var j = 0; j < elements.length; j++)
				{
					found[foundCount++] = elements[j];
				}
			}

			currentContext = new Array;
			var currentContextIndex = 0;
			var checkFunction; // This function will be used to filter the elements
			switch (attrOperator)
			{
				case '=': // Equality
					checkFunction = function(e) { return (e.getAttribute(attrName) == attrValue); };
					break;
				case '~': // Match one of space seperated words 
					checkFunction = function(e) { return (e.getAttribute(attrName).match(new RegExp('\\b'+attrValue+'\\b'))); };
					break;
				case '|': // Match start with value followed by optional hyphen
					checkFunction = function(e) { return (e.getAttribute(attrName).match(new RegExp('^'+attrValue+'-?'))); };
					break;
				case '^': // Match starts with value
					checkFunction = function(e) { return (e.getAttribute(attrName).indexOf(attrValue) == 0); };
					break;
				case '$': // Match ends with value - fails with "Warning" in Opera 7
					checkFunction = function(e) { return (e.getAttribute(attrName).lastIndexOf(attrValue) == e.getAttribute(attrName).length - attrValue.length); };
					break;
				case '*': // Match ends with value
					checkFunction = function(e) { return (e.getAttribute(attrName).indexOf(attrValue) > -1); };
					break;
				default :
					// Just test for existence of attribute
					checkFunction = function(e) { return e.getAttribute(attrName); };
			}

			currentContext = new Array;
			var currentContextIndex = 0;
			for (var k = 0; k < found.length; k++)
			{
				if (checkFunction(found[k]))
				{
					currentContext[currentContextIndex++] = found[k];
				}
			}

			// alert('Attribute Selector: '+tagName+' '+attrName+' '+attrOperator+' '+attrValue);
			continue; // Skip to next token
		}

	if (!currentContext[0])
	{
		return;
	}

	// If we get here, token is JUST an element (not a class or ID selector)
	tagName = token;
	var found = new Array;
	var foundCount = 0;
	for (var h = 0; h < currentContext.length; h++)
	{
		var elements = currentContext[h].getElementsByTagName(tagName);
		for (var j = 0; j < elements.length; j++)
		{
			found[foundCount++] = elements[j];
		}
	}

	currentContext = found;
	}
	return currentContext;
}

/* That revolting regular expression explained 
/^(\w+)\[(\w+)([=~\|\^\$\*]?)=?"?([^\]"]*)"?\]$/
  \---/  \---/\-------------/    \-------/
    |      |         |               |
    |      |         |           The value
    |      |    ~,|,^,$,* or =
    |   Attribute 
   Tag
*/