/*
find actual version of this library at:
http://www.fczbkk.com/js/dom/
*/

// library for working with multiple classes
var cls = {
	//return array witch contains all classes of element elm
	get : function (elm) {
		if (elm && elm.tagName) {
			var classes = [];
			if (elm.className) {	// na zaklade Centiho upozornenia o divnej interpretacii v Opere
				var cl = elm.className.replace(/\s+/g, " ");
				classes = cl.split(" ");
			}
			return classes;
		}
		return false;
	},
	// return true if element contains class
	has : function (elm, cl) {
		if ((actCl = cls.get(elm)) && (typeof(cl) == "string")) {
			for (var i = 0; i < actCl.length; i++) {
				if (actCl[i] == cl) {
					return true;
				}
			}
		}
		return false;
	},
	// add class of element
	add : function (elm, cl) {
		if ((actCl = cls.get(elm)) && (typeof(cl) == "string")) {
			if (!cls.has(elm, cl)) {
				elm.className += (actCl.length > 0) ? " " + cl : cl;
			}
			return true;
		}
		return false;
	}
}