skipping sunday in working day in js

Hi friends
I like to share some code to validate the date in number of days along with skipping sunday to validate working day in week.

<span id="result"></span>

var day= 14;
document.getElementById('result').innerHTML = addDays(day);
function addDays(day){
 var day = parseInt(day);
 
  var weekday = ["Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"];
        for(var i=0;i<=day;i++){   
            var dates = new Date();       
         dates.setDate(dates.getDate() + i);      
       //console.log(weekday[dates.getDay()]);
       if(weekday[dates.getDay()]=='Sunday'){      
       console.log('first if');                  
            console.log(day);
                   day = day+1;
       }
    }

           day = parseInt(day);
        var datess = new Date();
        datess.setDate(datess.getDate() + day); 
      if(weekday[datess.getDay()]=='Sunday'){  
      console.log('second if');
                    day = day+1;
           }
  
        var date = new Date();
    if(!isNaN(date.getTime())){
        date.setDate(date.getDate() + day);
        console.log(day);
       
        var monthNames = ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"];
        var weekday = ["Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"];
        if(isNaN(date.getDate())){
            return '';
        }
       
        return 'Ships on '+ weekday[date.getDay()]+', '+date.getDate()+' '+monthNames[date.getMonth()];
    }
    return false;
}