export function isWaiting(game, userid) {
  // a game is waiting if we are waiting and the player is not the first player already.
  return game.state == "waiting" && game.player1 != userid
}

export function joinGame(game, userid) {
  if (!isWaiting(game, userid)) {
    throw Error("Not waiting!")
  }
  if (game.player1 == undefined) {
    game.player1 = userid
  } else {
    game.player2 = userid
    game.state = "playing"
  }
}