wat

controllers.application\.js

import Controller from '@ember/controller';

export default class ApplicationController extends Controller {
  appName = 'Ember Twiddle';
}

router\.js

import { inject as service } from "@ember/service";
import EmberRouter from "@ember/routing/router";
import config from "./config/environment";

const PERMANENT_REDIRECTS = {
  "approve-store": "admin.approve-store",
};

class Router extends EmberRouter {
  location = 'none';
  rootURL = config.rootURL;

  @service router;

  willTransition(from, to) {
    super.willTransition(...arguments);
    console.log(from, to, this.router);
  }
}

Router.map(function () {
  this.route('demo');
  this.route('admin', function() {
    this.route('needs-auth');
  });
});

export default Router;

routes.admin.needs-auth\.js

import Route from '@ember/routing/route';

export default Route.extend({
});

routes.demo\.js

import Route from '@ember/routing/route';

export default Route.extend({
});

templates.application\.hbs

<h1>Welcome to {{this.appName}}</h1>
<br>
{{#link-to 'admin.needs-auth'}}Admin{{/link-to}}
<button {{on "click" this.goToAdminAuth}}>Via Button</button>
<br>
{{outlet}}
<br>
<br>

templates.demo\.hbs

<h1>Demo</h1>

twiddle\.json

{
  "version": "0.17.1",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.js",
    "ember": "3.18.1",
    "ember-template-compiler": "3.18.1",
    "ember-testing": "3.18.1"
  },
  "addons": {
    "@glimmer/component": "1.0.0"
  }
}