I had the same issue in AGoT:BG and I solved it by representing the state of the game as a tree. At any point of the game, the current game state is a leaf of the tree.
You'd represent this kind of choice as a child node. When the user has made their choice, the code can return to the parent node with the choice being made so it can continue with the next "step" of the game.
This is the correct response. Hearthstone is structured like this internally.
If you are curious about it, I wrote a cc0 spec which stores hearthstone game state in xml. It’s based on how hearthstone stores game state on the server and client, and it was the first time a replay format was created for hearthstone:
https://hearthsim.info/hsreplay/
Incidentally the UI we wrote for hearthstone replays is a react app. It’s funny because looking back it was the first time I used react and typescript, and both were not at all adopted by the js community yet at the time.
You'd represent this kind of choice as a child node. When the user has made their choice, the code can return to the parent node with the choice being made so it can continue with the next "step" of the game.