JSFiddle - React, Tailwind, and code Playground

by grant

HTML

<script src="http://ajax.microsoft.com/ajax/jquery.validate/1.7/jquery.validate.js"></script>
<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.4/themes/ui-lightness/jquery-ui.css">

JavaScript

var days = ['sunday', 'monday', 'tuesday', 'wednesday', 'thursday', 'friday', 'saturday'];

function next(day) {

    var today = new Date();
    var today_day = today.getDay();

    day = day.toLowerCase();

    for (var i = 7; i--;) {
        if (day === days[i]) {
            day = (i <= today_day) ? (i + 7) : i;
            break;
        }
    }

    var daysUntilNext = day - today_day;

    return new Date().setDate(today.getDate() + daysUntilNext);

}

// insert a week day
console.log(new Date(next( "Wednesday" )));
console.log(new Date(next( "sunday" )));