Generated by XState Viz: https://xstate.js.org/viz

machine.js

const gameMachine = Machine(
  {
    id: 'game',
    initial: 'playing',
    context: {
      points: 0
    },
    states: {
      playing: {
        // Eventless transition
        // Will transition to either 'win' or 'lose' immediately upon
        // entering 'playing' state or receiving AWARD_POINTS event
        // if the condition is met.
        always: [
          { target: 'win', cond: 'didPlayerWin' },
          { target: 'lose', cond: 'didPlayerLose' }
        ],
        on: {
          // Self-transition
          AWARD_POINTS: {
            actions: assign({
              points: 100
            })
          }
        }
      },
      win: { type: 'final' },
      lose: { type: 'final' }
    }
  },
  {
    guards: {
      didPlayerWin: (context, event) => {
        console.log(context.points);
        // check if player won
        return context.points > 99;
      },
      didPlayerLose: (context, event) => {
        console.log(context.points);
        // check if player lost
        return context.points < 0;
      }
    }
  }
);