JSFiddle - React, Tailwind, and code Playground

JavaScript

var CHAR_SETS = {
    d: '0123456789',
    A: 'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
    w: '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ'
};

function randChar(charType) {
    var chars = CHAR_SETS[charType];
    return chars.charAt(parseInt(Math.random() * chars.length));
}
console.log('Add-wwww-AAA-ddA'.replace(/[Adw]/g, randChar));