Date.abbrDayNames = ['dom', 'lun', 'mar', 'mi?', 'jue', 'vie', 's?b'];
switch(idioma){
	case 'es':
		Date.monthNames = ['enero', 'febrero', 'marzo', 'abril', 'mayo', 'junio', 'julio', 'agosto', 'septiembre', 'octubre', 'noviembre', 'diciembre'];
		Date.dayNames = ['domingo', 'lunes', 'martes', 'miércoles', 'jueves', 'viernes', 'sábado'];
	break;
	case 'fr':
		Date.monthNames = ['janvier', 'février', 'mars', 'avril', 'mai', 'juin', 'juillet', 'août', 'septembre', 'octobre', 'novembre', 'décembre'];
		Date.dayNames = ['dimanche', 'lundi ', 'mardi ', 'mercredi ', 'jeudi ', 'vendredi ', 'samedi'];
	break;
	case 'de':
		Date.monthNames = ['januar', 'februar', 'märz', 'april', 'mai', 'juni', 'juli', 'august', 'september', 'oktober', 'november', 'dezember'];
		Date.dayNames = ['sonntag', 'montag', 'dienstag', 'mittwoch', 'donnerstag', 'freitag', 'samstag'];
	break;
	case 'uk':
		Date.monthNames = ['january', 'february', 'march', 'april', 'may', 'june', 'july', 'august', 'september', 'october', 'november', 'december'];
		Date.dayNames = ['sunday', 'monday', 'tuesday', 'wednesday', 'thursday', 'friday', 'saturday'];
	break;
	case 'nl':
		Date.monthNames = ['januari', 'februari', 'maart', 'april', 'mei', 'juni', 'juli', 'augustus', 'september', 'october', 'november', 'december'];
		Date.dayNames = ['zondag', 'maandag', 'dinsdag', 'woensdag', 'donderdag', 'vrijdag', 'zaterdag'];
	break;
}
//

Date.abbrMonthNames = ['ene', 'feb', 'mar', 'abr', 'may', 'jun', 'jul', 'ago', 'sep', 'oct', 'nov', 'dic'];
Date.firstDayOfWeek = 1;
Date.format = 'dd/mm/yyyy';
Date.fullYearStart = '20';

(function() {
	function add(name, method) {
		if( !Date.prototype[name] ) {
			Date.prototype[name] = method;
		}
	};
	add("isLeapYear", function() {
		var y = this.getFullYear();
		return (y%4==0 && y%100!=0) || y%400==0;
	});
	add("isWeekend", function() {
		return this.getDay()==0 || this.getDay()==6;
	});
	add("isWeekDay", function() {
		return !this.isWeekend();
	});
	add("getDaysInMonth", function() {
		return [31,(this.isLeapYear() ? 29:28),31,30,31,30,31,31,30,31,30,31][this.getMonth()];
	});
	add("getDayName", function(abbreviated) {
		return abbreviated ? Date.abbrDayNames[this.getDay()] : Date.dayNames[this.getDay()];
	});
	add("getMonthName", function(abbreviated) {
		return abbreviated ? Date.abbrMonthNames[this.getMonth()] : Date.monthNames[this.getMonth()];
	});
	add("getDayOfYear", function() {
		var tmpdtm = new Date("1/1/" + this.getFullYear());
		return Math.floor((this.getTime() - tmpdtm.getTime()) / 86400000);
	});
	add("getWeekOfYear", function() {
		return Math.ceil(this.getDayOfYear() / 7);
	});
	add("setDayOfYear", function(day) {
		this.setMonth(0);
		this.setDate(day);
		return this;
	});
	add("addYears", function(num) {
		this.setFullYear(this.getFullYear() + num);
		return this;
	});
	add("addMonths", function(num) {
		var tmpdtm = this.getDate();
		
		this.setMonth(this.getMonth() + num);
		
		if (tmpdtm > this.getDate())
			this.addDays(-this.getDate());
		
		return this;
	});
	add("addDays", function(num) {
		this.setDate(this.getDate() + num);
		return this;
	});
	add("addHours", function(num) {
		this.setHours(this.getHours() + num);
		return this;
	});
	add("addMinutes", function(num) {
		this.setMinutes(this.getMinutes() + num);
		return this;
	});
	add("addSeconds", function(num) {
		this.setSeconds(this.getSeconds() + num);
		return this;
	});
	add("zeroTime", function() {
		this.setMilliseconds(0);
		this.setSeconds(0);
		this.setMinutes(0);
		this.setHours(0);
		return this;
	});
	add("asString", function() {
		var r = Date.format;
		return r
			.split('yyyy').join(this.getFullYear())
			.split('yy').join((this.getFullYear() + '').substring(2))
			.split('mmm').join(this.getMonthName(true))
			.split('mm').join(_zeroPad(this.getMonth()+1))
			.split('dd').join(_zeroPad(this.getDate()));
	});
	Date.fromString = function(s)
	{
		var f = Date.format;
		var d = new Date('01/01/1977');
		var iY = f.indexOf('yyyy');
		if (iY > -1) {
			d.setFullYear(Number(s.substr(iY, 4)));
		} else {
			// TODO - this doesn't work very well - are there any rules for what is meant by a two digit year?
			d.setFullYear(Number(Date.fullYearStart + s.substr(f.indexOf('yy'), 2)));
		}
		var iM = f.indexOf('mmm');
		if (iM > -1) {
			var mStr = s.substr(iM, 3);
			for (var i=0; i<Date.abbrMonthNames.length; i++) {
				if (Date.abbrMonthNames[i] == mStr) break;
			}
			d.setMonth(i);
		} else {
			d.setMonth(Number(s.substr(f.indexOf('mm'), 2)) - 1);
		}
		d.setDate(Number(s.substr(f.indexOf('dd'), 2)));
		if (isNaN(d.getTime())) {
			return false;
		}
		return d;
	};
	var _zeroPad = function(num) {
		var s = '0'+num;
		return s.substring(s.length-2)
	};
	
})();