const paymentService = (context, event) =>
  new Promise((resolve, reject) => {
    // TODO: change this, it's MOCK
    setTimeout(() => {
      if (context.plan === 'annual') {
        return reject('something went wrong');
      }

      return resolve();
    }, 2000);
  });


const subscribeToCoachMachine = Machine({
    id: 'subscribeToCoach',
    context: {
      plan: 'free',
      error: undefined,
    },
    initial: 'planSelection',
    states: {
      planSelection: {
        on: {
          SUBSCRIBE: [
            // only go to payment if the plan is not a free one
            { target: 'enterPaymentInfo', cond: 'notFreePlan' },
            { target: 'subscribed', cond: 'isFreePlan' },
          ],
          SELECT: {
            actions: 'selectPlan',
          },
        },
      },
      enterPaymentInfo: {
        on: {
          PAYMENT: {
            target: 'paymentProcess',
          },
        },
      },
      paymentProcess: {
        invoke: {
          id: 'paymentService',
          src: paymentService,
          onDone: {
            target: 'subscribed',
            actions: [],
          },
          onError: {
            target: 'enterPaymentInfo',
            actions: assign({ error: (context, event) => event.data }),
          },
        },
      },
      subscribed: {},
    },
  },
  {
    actions: {
      selectPlan: assign({
        plan: (_, event) => event.plan,
      }),
    },
    guards: {
      notFreePlan: (context) => {
        return context.plan !== 'free';
      },
      isFreePlan: (context) => {
        return context.plan === 'free';
      },
    },
  });