Actors' code is too complicated

[survived]

There're two actors that were introduced into the code to handle shared state more nicely. Though using actors pattern achieves its main goal here: no mutex or other sync primitives are used, code got very hard to read. I believe that the main reason why it looks odd is because of having long chains of .map() .then() methods in order to access to actor's state. Probably it would look better if it were written using this approach: Actors with Tokio