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

emergencyCallMachine.js

const dialTimeout = 7000;
const answerTimeout = 7000;

const externalActions = {
  notify: () => {
    window.alert('Notified care circle');
  }
}

const dialActor = (timeout = 5000) => {
  return new Promise((resolve, reject) => {
    setTimeout(resolve, timeout)
  })
}

const guards = {
  shouldContactCaree: (ctx, event) => {
    return ctx.shouldContactCaree
  },
  maxAttemptsReached: (ctx, event, { cond }) => {
    return ctx[cond.actor].attempts >= cond.numAttempts && !ctx[cond.actor].success
  },
  maxAttempsCurrentCarerReached: (ctx, event, { cond }) => {
    return ctx.carers[ctx.currentCarerIndex].attempts >= cond.numAttempts && !ctx.carers[ctx.currentCarerIndex].success
  },
  couldNotContactCarers: (ctx, event, { cond }) => {
    return ctx.carers.every((carer, i) => !carer.success && carer.attempts === ctx.numCarerAttempts);
  }
}

const emergencyMachine = Machine({
  id: 'emergency',
  context: {
    shouldContactCaree: true,
    currentCarerIndex: 0,
    numCarerAttempts: 1,
    caree: {
      attempts: 0,
      success: false,
      firstName: 'John',
      lastName: 'Doe',
      phone: '+32411111111'
    },
    carers: [{
      attempts: 0,
      success: false,
      firstName: 'Michiel',
      lastName: 'De Mey',
      phone: '+32411118b61111'
    }, {
      attempts: 0,
      success: false,
      firstName: 'Niels',
      lastName: 'Peetermans',
      phone: '+32411111111'
    }, {
      attempts: 0,
      success: false,
      firstName: 'Jane',
      lastName: 'Doe',
      phone: '+32411111111'
    }]
  },
  initial: 'idle',
  states: {
    idle: {
      on: {
        INCOMING_EMERGENCY: [{
          target: 'contactingCaree',
          cond: {
            type: 'shouldContactCaree'
          }
        }, {
          target: 'contactingCarers',
        }]
      }
    },
    contactingCaree: {
      initial: 'check',
      states: {
        check: {
          on: {
            '': [{
              target: '#emergency.contactingCarers',
              cond: {
                type: 'maxAttemptsReached',
                actor: 'caree',
                numAttempts: 1
              }
            }, { target: 'queue' }]
          }
        },
        queue: {
          exit: ['increaseCareeAttempt'],
          invoke: {
            id: 'dialCaree',
            src: () => dialActor(),
            onDone: {
              target: 'dialing',
            },
            onError: {
              target: '#emergency.contactingCaree'
            }
          }
        },
        dialing: {
          on: {
            ANSWER: {
              target: 'answer'
            },
            NO_ANSWER: [{
              target: '#emergency.contactingCaree',
            }]
          },
          after: {
            [dialTimeout]: '#emergency.contactingCaree'
          }
        },
        answer: {
          on: {
            REAL_EMERGENCY: {
              target: '#emergency.contactingCarers',
              actions: ['successfulCareeAttempt']
            },
            FALSE_ALARM: {
              target: '#emergency.end',
              actions: ['successfulCareeAttempt']
            },
            HANGUP: '#emergency.contactingCaree'
          },
          after: {
            [dialTimeout]: '#emergency.contactingCaree'
          }
        }
      },
    },
    contactingCarers: {
      initial: 'check',
      states: {
        check: {
          entry: ['attemptCarer'],
          on: {
            '': [{
              target: '#emergency.notify',
              cond: 'couldNotContactCarers'
            }, { target: 'queue' }]
          }
        },
        queue: {
          exit: ['increaseCarersAttempt'],
          invoke: {
            id: 'dialCarer',
            src: () => dialActor(),
            onDone: {
              target: 'dialing',
            },
            onError: {
              target: '#emergency.contactingCarers',
            }
          }
        },
        dialing: {
          on: {
            ANSWER: {
              target: 'answer'
            },
            NO_ANSWER: [{
              target: '#emergency.contactingCarers'
            }]
          },
          after: {
            [dialTimeout]: '#emergency.contactingCarers'
          }
        },
        answer: {
          on: {
            CONFIRM: {
              target: '#emergency.end',
              actions: ['successfulCarerAttempt']
            },
            HANGUP: '#emergency.contactingCarers'
          },
          after: {
            [answerTimeout]: '#emergency.contactingCarers'
          }
        }
      }
    },
    notify: {
      entry: ['notify'],
      on: {
        '': 'end'
      }
    },
    end: {
      type: 'final'
    }
  }
}, {
  actions: {
    ...externalActions,
    increaseCareeAttempt: assign({
      caree: (ctx, event) => {
        return {
          ...ctx.caree,
          attempts: ctx.caree.attempts + 1
        }
      }
    }),
    successfulCareeAttempt: assign({
      caree: (ctx, event) => {
        return {
          ...ctx.caree,
          success: true
        }
      }
    }),
    increaseCarersAttempt: assign({
      carers: (ctx, event) => {
        const carerArr = [ ...ctx.carers ]
        
        const currentAttempts = carerArr[ctx.currentCarerIndex].attempts;
        
        carerArr[ctx.currentCarerIndex] = {
          ...ctx.carers[ctx.currentCarerIndex],
          attempts: currentAttempts + 1
        }
        
        return carerArr
      }
    }),
    attemptCarer: assign({
      currentCarerIndex: (ctx, event) => {
        if (ctx.carers[ctx.currentCarerIndex].attempts < ctx.numCarerAttempts) return ctx.currentCarerIndex;
        
        return ctx.currentCarerIndex + 1
      }
    }),
    successfulCarerAttempt: assign({
      carers: (ctx, event) => {
        const carerArr = [ ...ctx.carers ]
        
        carerArr[ctx.currentCarerIndex] = {
          ...carerArr[ctx.currentCarerIndex],
          success: true
        }
        
        return carerArr
      }
    })
  },
  guards
});