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const monthList = ["January", "February", "March", "April", "May", "June",
  "July", "August", "September", "October", "November", "December"
];
const weekdays = ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"];

function check_holiday (dt_date) {  // check for market holidays
// dt_date = new Date("2017-04-14T12:01:00Z"); // for testing purposes
	// check simple dates (month/date - no leading zeroes)
	var n_date = dt_date.getDate();
	var n_month = dt_date.getMonth() + 1;
	var s_date1 = n_month + '/' + n_date;
	var s_year = dt_date.getFullYear();
	var s_day = dt_date.getDay(); // day of the week 0-6
	switch(s_date1){
		case '1/1':
		return "New Year's";
		case '7/4':
		return "Independence Day";
		case '12/25':
		return "Christmas";
		case GoodFriday(s_year):
		return "Good Friday";
		}
	// special cases - friday before or monday after weekend holiday
	if (s_day == 5){  // Friday before
		switch(s_date1){
			case '12/31':
			return "New Year's";
			case '7/3':
			return "Independence Day";
			case '12/24':
			return "Christmas";
			}
		}
	if (s_day == 1){  // Monday after
		switch(s_date1){
			case '1/2':
			return "New Year's";
			case '7/5':
			return "Independence Day";
			case '12/26':
			return "Christmas";
			}
		}
	// weekday from beginning of the month (month/num/day)
	var n_wday = dt_date.getDay();
	var n_wnum = Math.floor((n_date - 1) / 7) + 1;
	var s_date2 = n_month + '/' + n_wnum + '/' + n_wday;
	switch(s_date2){
		case '1/3/1':
		return "ML King Birthday";
		case '2/3/1':
		return "President's Day";
		case '9/1/1':
		return "Labor Day";
		case '11/4/4':
		return "Thanksgiving";
		}
	// weekday number from end of the month (month/num/day)
	var dt_temp = new Date (dt_date);
	dt_temp.setDate(1);
	dt_temp.setMonth(dt_temp.getMonth() + 1);
	dt_temp.setDate(dt_temp.getDate() - 1);
	n_wnum = Math.floor((dt_temp.getDate() - n_date) / 7) + 1;
	var s_date3 = n_month + '/' + n_wnum + '/' + n_wday;
	if (   s_date3 == '5/1/1'  // Memorial Day, last Monday in May
	) return 'Memorial Day';
	// misc complex dates
//	if (s_date1 == '1/20' && (((dt_date.getFullYear() - 1937) % 4) == 0)
	// Inauguration Day, January 20th every four years, starting in 1937.
//	) return 'Inauguration Day';
//	if (n_month == 11 && n_date >= 2 && n_date < 9 && n_wday == 2
	// Election Day, Tuesday on or after November 2.
//	) return 'Election Day';
	return false;
} 
function GoodFriday(Y) {  // calculates Easter Sunday and subtracts 2 days
    var C = Math.floor(Y/100);
    var N = Y - 19*Math.floor(Y/19);
    var K = Math.floor((C - 17)/25);
    var I = C - Math.floor(C/4) - Math.floor((C - K)/3) + 19*N + 15;
    I = I - 30*Math.floor((I/30));
    I = I - Math.floor(I/28)*(1 - Math.floor(I/28)*Math.floor(29/(I + 1))*Math.floor((21 - N)/11));
    var J = Y + Math.floor(Y/4) + I + 2 - C + Math.floor(C/4);
    J = J - 7*Math.floor(J/7);
    var L = I - J;
    var M = 3 + Math.floor((L + 40)/44);
    var D = L + 28 - 31*Math.floor(M/4);
    //
    D = D-2;  // subtract 2 days for Good Friday
    if (D <= 0){
    	D = D + 31;	// correct day if we went back to March
    	M = 3;			// correct month
    	}
    return parseInt(M, 10) + '/' + parseInt(D, 10);  // return without any leading zeros
}

function addDays(dateObj, numDays) {
   dateObj.setDate(dateObj.getDate() + numDays);
   return dateObj;
}

function checkWeekend (nextWeek)
{
  if (nextWeek.getDay() == 6)
  {
    //alert("This date is a Saturday.");
    var nextWeek = addDays(nextWeek , 2);
  }
else if (nextWeek.getDay() == 0)
{
  //alert("This date is a Sunday.");
  var nextWeek = addDays(nextWeek , 1);
}
return nextWeek;
}

function deliveryDateEst() {
$( ".CE__shipping-component ul.bordered-ul li:not(.extended-li) .checkbox-row .ch-custom-label" ).each(function() {
  var fullLabel = $( this ).find("span:eq(0)").text();
  var currentLabel = $( this ).find("span:eq(1)").text();
console.log(currentLabel);
var slug = currentLabel.split('(').pop();
var slug = slug.charAt(0);
var slug = parseInt(slug);
var now = new Date(); //Current date
var nextWeek = addDays(now , slug);
var isHoliday = check_holiday(nextWeek);
if(isHoliday != false) {
    var nextWeek = addDays(nextWeek , 1);
} 
var nextWeek = checkWeekend(nextWeek);
//Format date
var month = monthList[nextWeek.getMonth()]; //months from 1-12
var day = nextWeek.getDate();
var dateFormat = month + " " + day;
console.log(dateFormat);
var res = currentLabel.replace(currentLabel, "(Est. delivery date is  " + dateFormat + ")");
$( this ).find("span:eq(1)").text(res);
});
  }

var checkExist = setInterval(function() {
   if ($('.CE__shipping-component ul.bordered-ul li:not(.extended-li) .checkbox-row .ch-custom-label').text().indexOf('Standard') > -1) {
      console.log("Exists!");
      deliveryDateEst();
      clearInterval(checkExist);
   }
  else {
    console.log("Not yet.");
    
  }
}, 1000);