var W3CDOM = (document.createElement && document.getElementsByTagName);

/*
	Add Load Event: written by Simon Willison (http://simon.incutio.com/archive/2004/05/26/addLoadEvent)
*/
function addLoadEvent(func) {
	var oldonload = window.onload;
	if (typeof window.onload != 'function') {
		window.onload = func;
	} else {
		window.onload = function() {
			oldonload();
			func();
		}
	}
}


function getElementsByClassName(oElm, strTagName, oClassNames){
	var arrElements = (strTagName == "*" && oElm.all)? oElm.all : oElm.getElementsByTagName(strTagName);
	var arrReturnElements = new Array();
	var arrRegExpClassNames = new Array();
	if(typeof oClassNames == "object"){
		for(var i=0; i<oClassNames.length; i++){
			arrRegExpClassNames.push(new RegExp("(^|\s)" + oClassNames[i].replace(/-/g, "\-") + "(\s|$)"));
		}
	}
	else{
		arrRegExpClassNames.push(new RegExp("(^|\s)" + oClassNames.replace(/-/g, "\-") + "(\s|$)"));
	}
	var oElement;
	var bMatchesAll;
	for(var j=0; j<arrElements.length; j++){
		oElement = arrElements[j];
		bMatchesAll = true;
		for(var k=0; k<arrRegExpClassNames.length; k++){
			if(!arrRegExpClassNames[k].test(oElement.className)){
				bMatchesAll = false;
				break;
			}
		}
		if(bMatchesAll){
			arrReturnElements.push(oElement);
		}
	}
	return (arrReturnElements)
}

function addClass(target, classValue)
{
    if (!hasClass(target, classValue))
    {
        if (target.className == "")
        {
            target.className = classValue;
        }
        else
        {
            target.className += " " + classValue;
        }
    }

    return true;
};




function removeClass(target, classValue)
{
    var removedClass = target.className;
    var pattern = new RegExp("(^| )" + classValue + "( |$)");

    removedClass = removedClass.replace(pattern, "$1");
    removedClass = removedClass.replace(/ $/, "");

    target.className = removedClass;

    return true;
};




function hasClass(target, classValue)
{
    var pattern = new RegExp("(^| )" + classValue + "( |$)");
    
    if (target.className.match(pattern))
    {
    	return true;
    }
    
    return false;
};