Trying to write a simple next/last day thingy with Moment.

gistfile1.js

var moment = require('moment');

function Datey() {
	this.date = moment();
	this.modifier = 1;
	return this;
}

Datey.prototype.last = function() {
	this.modifier = -1;
	return this;
}

Datey.prototype.next = function() {
	this.modifier = 1;
	return this;
}

Datey.prototype.sunday = function() {
	return this.offset(7);
}

Datey.prototype.monday = function() {
	return this.offset(1);
}

Datey.prototype.tuesday = function() {
	return this.offset(2);
}

Datey.prototype.wednesday = function() {
	return this.offset(3);
}

Datey.prototype.thursday = function() {
	return this.offset(4);
}

Datey.prototype.friday = function() {
	return this.offset(5);
}

Datey.prototype.saturday = function() {
	return this.offset(6);
}

Datey.prototype.offset = function(d) {
	var day = this.date.isoWeekday();
	if (d >= day && this.modifier < 0) d -= 7;
	if (d <= day && this.modifier > 0) d += 7;
	return this.date.clone().isoWeekday(d).format('ddd Do');
}

var d = new Datey();



console.log('last tue',d.last().tuesday());
console.log('last wed',d.last().wednesday());
console.log('last thu',d.last().thursday());
console.log('last fri',d.last().friday());
console.log('last sat',d.last().saturday()); // -1
console.log('last sun',d.last().sunday()); // 0
console.log('last mon',d.last().monday()); // 1
console.log(moment().format('ddd Do'),'<< Now');
console.log('next wed',d.next().wednesday());
console.log('next thu',d.next().thursday());
console.log('next fri',d.next().friday());
console.log('next sat',d.next().saturday());
console.log('next sun',d.next().sunday());
console.log('next mon',d.next().monday());
console.log('next tue',d.next().tuesday());

/*
		 s  m  t  w  t  f  s
weekdays 0  1  2  3  4  5  6 
last     0  1  * -4 -3 -2 -1
next
*/