// these vars are used as masks
var _ROUND_UPPER = 1
var _ROUND_LOWER = 2;

// cls: className; used to select the elements to round
// img: imageName; name of the corner image
// mask: 1, 2, or 3 (1 for top only, 2 for bottom only, 3 for all)
// size: size (in pixels) of a single corner in the corner image
function roundCorners(cls,img,mask,size){
    if (mask == null) mask = 3;
    if (size == null) size = 10;
    var els = getElementsByClassName(cls);
    for (var i = 0; i < els.length; i++) {
        var el = els[i];
        var c=new Array(4);
        for(var j=0;j<4;j++){
            c[j]=document.createElement("b");
            c[j].style.display="block";
            c[j].style.height=size+"px";
            c[j].style.fontSize="1px";
            c[j].style.border="none";
            c[j].style.padding="0px";
            c[j].style.margin="0px";
            if(j%2==0)
                c[j].style.background="url("+img+") no-repeat 0 -"+ j*size + "px";
            else
                c[j].style.background="url("+img+") no-repeat 100% -"+ j*size + "px";
        }
        if (mask & _ROUND_UPPER) {
            c[0].appendChild(c[1]);
            el.insertBefore(c[0], el.firstChild);
        }
        if (mask & _ROUND_LOWER) {
            c[2].appendChild(c[3]);
            el.appendChild(c[2]);
        }
        el.style.padding="0";
        el.style.border="none";
    }
}

/*
	Developed by Robert Nyman, http://www.robertnyman.com
	Code/licensing: http://code.google.com/p/getelementsbyclassname/
*/
var getElementsByClassName = function (className, tag, elm){
	if (document.getElementsByClassName) {
		getElementsByClassName = function (className, tag, elm) {
			elm = elm || document;
			var elements = elm.getElementsByClassName(className),
				nodeName = (tag)? new RegExp("\\b" + tag + "\\b", "i") : null,
				returnElements = [],
				current;
			for(var i=0, il=elements.length; i<il; i+=1){
				current = elements[i];
				if(!nodeName || nodeName.test(current.nodeName)) {
					returnElements.push(current);
				}
			}
			return returnElements;
		};
	}
	else if (document.evaluate) {
		getElementsByClassName = function (className, tag, elm) {
			tag = tag || "*";
			elm = elm || document;
			var classes = className.split(" "),
				classesToCheck = "",
				xhtmlNamespace = "http://www.w3.org/1999/xhtml",
				namespaceResolver = (document.documentElement.namespaceURI === xhtmlNamespace)? xhtmlNamespace : null,
				returnElements = [],
				elements,
				node;
			for(var j=0, jl=classes.length; j<jl; j+=1){
				classesToCheck += "[contains(concat(' ', @class, ' '), ' " + classes[j] + " ')]";
			}
			try	{
				elements = document.evaluate(".//" + tag + classesToCheck, elm, namespaceResolver, 0, null);
			}
			catch (e) {
				elements = document.evaluate(".//" + tag + classesToCheck, elm, null, 0, null);
			}
			while ((node = elements.iterateNext())) {
				returnElements.push(node);
			}
			return returnElements;
		};
	}
	else {
		getElementsByClassName = function (className, tag, elm) {
			tag = tag || "*";
			elm = elm || document;
			var classes = className.split(" "),
				classesToCheck = [],
				elements = (tag === "*" && elm.all)? elm.all : elm.getElementsByTagName(tag),
				current,
				returnElements = [],
				match;
			for(var k=0, kl=classes.length; k<kl; k+=1){
				classesToCheck.push(new RegExp("(^|\\s)" + classes[k] + "(\\s|$)"));
			}
			for(var l=0, ll=elements.length; l<ll; l+=1){
				current = elements[l];
				match = false;
				for(var m=0, ml=classesToCheck.length; m<ml; m+=1){
					match = classesToCheck[m].test(current.className);
					if (!match) {
						break;
					}
				}
				if (match) {
					returnElements.push(current);
				}
			}
			return returnElements;
		};
	}
	return getElementsByClassName(className, tag, elm);
};