JS CustomEvent params being passed as undefined in Angular

I am trying to call an Angular function from within JS, however the parameters being passed to Angular are undefined. What am I missing? Ideally I would like to return a result from a dispatchedEvent as well. Is there a better solution I should be using?

JS function

  var event = new CustomEvent('test', {
    id: "a", id2:"ttt"
  });
  window.dispatchEvent(event);

Angular component

  @HostListener('window:test', ['$event.id','$event.id2'])
  test(id,id2) {
    console.log('ang called from JS: '+id+' '+id2)
  }

Output to console: ang called from JS: undefined undefined

GOAL: ang called from JS: a ttt

As far as I know, you can only pass one parameter to CustomEvent, which is detail. So, your code should not be compilable. You need to change it as

onClick() {
  const event = new CustomEvent('test', {
    detail: {
      id: 'a', id2: 'ttt'
    }
  });
  window.dispatchEvent(event);
}

After this, your handler will be

@HostListener('window:test', ['$event.detail.id', '$event.detail.id2'])
test(id, id2) {
  console.log('ang called from JS: ' + id + ' ' + id2);
}