What is the best way to create a Code-a-Pillar copy? Answered

Greetings! I'm trying to understand how to make my own Coda-a-Pillar copy

https://fisher-price.mattel.com/shop/en-us/fp/thin...

The functionality can be reduced to basically the "head" being able to tell, what is the sequence of rings that are connected to it.

How do I do it with an Arduino or Raspberry pie? What has to be inside each ring?