Start/End Date Ranges Based on Dropdown Option Selected

Based on the selected option, the date range will either be a date range of 30 days or any future date.

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.14/themes/base/jquery-ui.css">
<script src="http://code.jquery.com/ui/1.11.0/jquery-ui.js"></script>
<input type="text" id="datepicker1">
<input type="text" id="datepicker2">

JavaScript

var timestamp = new Date().getTime() - (30 * 24 * 60 * 60 * 1000);
$("#datepicker1").datepicker({
            dateFormat: "dd-M-yy",
            maxDate: 0,
           	onSelect: function (date) {
                var date1 = $(this).datepicker('getDate');
                var date2 = $(this).datepicker('getDate');
               	date1.setDate(date1.getDate() + 30);             
               	$('#datepicker2').datepicker('option', 'minDate', date2);
                $('#datepicker2').datepicker('option', 'maxDate', date1);
           }
           
        });
        
        $('#datepicker2').datepicker({
            dateFormat: "dd-M-yy",
            maxDate: 0,
            onSelect: function (date) {
                var date1 = $(this).datepicker('getDate');
                var date2 = $(this).datepicker('getDate');
               	date1.setDate(date1.getDate() - 30);             
               	$('#datepicker1').datepicker('option', 'minDate', date1);
                $('#datepicker1').datepicker('option', 'maxDate', date2);           
            }
        });