Dependent product variation type I have a question.
My site sells tours.
For each tour(product) a user can choose a flight  and some hotel rooms.
Example tour1: 
user can choose: flight1 and flight2.
user can choose: double rooms and/or single rooms.
If the user choose flight1 then ->  double rooms costs 50, single rooms costs 100(a).
If the user choose flight2 then -> double rooms costs 150, single rooms costs 200 (b).
I have 3 dependent variation types(flight, doubleRoom, singleRoom). What I want is:
if the user choose flight1 I only show double rooms = 50, single rooms  =100 (rooms(a));
if the user choose flight2 I only show double rooms = 150, single rooms=200 (rooms(b)).
Flights and rooms have  a taxonomy terms called 'solution':solution1, solution2 ecc..
I think that a way should be use rules, with event 'After adding a product to the cart' but I can't write the condition('if flight  choose solution1') and the action(set visible=true where rooms solution= solution1).
Can someone help me please??
Thanks in advice
I am looking for this for Drupal 8, however it appears that the module Commerce Product Add-on provides a solution for Drupal 7 (I have not tested it).


  Commerce Product Add-On allows users to attach products as options to
  the add to cart form of another product. This is particularly useful
  for things like event sponsorship, optional accessories, and other
  up-sells.