var Cookie = Class.create();
Object.extend(Cookie.prototype, {
	initialize: function(name){
		this.name = name;
		this.update();
	},
	update: function(){
		this.value = this.read();
	},
	read: function(){
		var nameEQ = this.name + "=";
		var ca = document.cookie.split(';');
		for(var i=0;i < ca.length;i++) {
			var c = ca[i];
			while (c.charAt(0)==' ') c = c.substring(1,c.length);
			if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
		}
		return null;
	},
	set: function(value, days){
		if(!days) days = 30;
		if (days) {
			var date = new Date();
			date.setTime(date.getTime()+(days*24*60*60*1000));
			var expires = "; expires="+date.toGMTString();
		}
		else var expires = "";
		document.cookie = this.name+"="+value+expires+"; path=/";
		this.value = value;
	},
	erase: function(){
		this.set('', -1);
	}
});