Build a month

month.js

var month = []
    
var fullyear = (new Date()).getFullYear(); // The year you want to start with
var fullmonth = (new Date()).getMonth(); // The month you want (0-11)

var currentDate = new Date(fullyear, fullmonth, 1);
var currentDay = new Date((new Date()).getFullYear(), (new Date()).getMonth(), 1).getDate();
var lastDay = new Date((new Date()).getFullYear(), (new Date()).getMonth() + 1, 0).getDate();

while (currentDay <= lastDay) {

  var week = [];

  for (var i = currentDate.getDay(); i < 7; i++) {
    week[i] = currentDay;

    currentDay++;
    currentDate = new Date(fullyear, fullmonth, currentDay);
  }

  month.push(week)
}