reset behavior of activePlayers

Spawning off a thread from a previous discussion at #442, which is talking about (among other things) what to do to activePlayers after it becomes empty (this is a new concept in the phases-overhaul branch).

Background

activePlayers is a map that keeps track of all the players that can make a move on the current turn. This is an evolution of the current concept actionPlayers. It also keeps track of what “stage” each active player is in. A “stage” is analogous to a “phase”, and basically restricts what moves the player in that stage can make. It can be manipulated using something like this:

setActivePlayers({ others: 'discard', once: true });

which does the following things:

• put every player (other than the current player) in activePlayers.
• sets the stages of those players to discard.
• allows them to make one move before removing them from activePlayers.

This allows implementing cards that allow other players to take an action before reverting back to the current player (the Militia card in Dominion, for example).

Problem

Players are removed from activePlayers once they make a move. After activePlayers becomes empty, it is set to null (which means that only the current player can play, but they are not in any stage).

However, if the currentPlayer was in a stage to begin with (i.e. activePlayers was something like { currentPlayer: 'play' } before setActivePlayers was called), then this state is lost.

Proposals

1. Reset activePlayers to the previous state before setActivePlayers was called once it becomes empty.

2. Pass in the state to reset to in the setActionPlayers call itself.

Notes

• Both proposals need to clearly define when to trigger the reset behavior. Is it sufficient to just assume that a reset is required when activePlayers becomes empty?

[nicolodavis]

That’s a good point. Maybe we should just support moveLimit: 2 instead of the more verbose version.

[nicolodavis]

Yeah, let’s go for the bare minimum since this is a new API and add stuff as we encounter use-cases that are difficult to implement.

I’m working on setPhase / endPhase BTW.