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

machine.js

const MOISTURE_LEVEL = {
  WET: 1,
  DRY: 0,
}


const soilMachine = Machine(
  {
    id: 'soil',
    initial: 'startup',
    context: {
      notificationSent: false,
      previousReading: null,
      currentReading: null,
    },
    states: {
      startup: {
        on: {
          SETUP: {
            actions: ['setup', 'initialReading'],
            target: 'idle',
          },
        },
      },
      idle: {
        after: {
          5000: 'running',
        },
      },
      running: {
        on: {
          '': {
            actions: 'checkPin',
            target: 'sendingAlert',
          },
        },
      },
      sendingAlert: {
        on: {
          '': [
            {
              cond: 'shouldSendAlert',
              actions: 'sendAlert',
              target: 'idle',
            },
            { target: 'idle' },
          ],
        },
      },
    },
  },
  {
    actions: {
      setup: () => console.log('setup'),
      initialReading: assign((ctx, evt) => ({
        previousReading: 1,
        currentReading: 1,
      })),
      checkPin: assign((ctx, evt) => {
        console.log('Checking Pin')
        return {
          previousReading: ctx.currentReading,
          currentReading: Math.round(Math.random()),
        }
      }),
      sendAlert: () => {
        console.log('FEED ME SEYMOUR!')
      },
    },
    guards: {
      isWet: (ctx, evt) => ctx.currentReading === MOISTURE_LEVEL.WET,
      shouldSendAlert: (ctx, evt) => {
        return ctx.previousReading !== ctx.currentReading && ctx.currentReading === MOISTURE_LEVEL.DRY
      },
    },
  }
)