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

machine.js

  // Available variables:
  // - Machine
  // - interpret
  // - assign
  // - send
  // - sendParent
  // - spawn
  // - raise
  // - actions
  // - XState (all XState exports)
  function getInputMachine(id) {
    const changeEventName = `CHANGE_${id.toUpperCase()}`
    function validator(ctx, e) {
      return e.text && e.text.length > 4
    }
    
    function isValid(ctx, e) {
      console.log('isValid', validator(ctx, e))
      return validator(ctx, e);
    }
    
    function isInvalid(ctx, e) {
      console.log('isInvalid', !validator(ctx, e))
      return !validator(ctx, e);
    }
    
    const inputStateMachine = {
      id,
      initial: 'Valid',
      context: {
        text: 'abc'
      },
      states: {
        // state names of parallel machines can
        // be namespaced with the higher level 
        // name given to the machine. E.g. username.Active and password.active are different. But the event names are same for all the machines inside the big machine. That is why had to create unique event names for each machine which are created using the constructor function
        Valid: {
          on: {
            [changeEventName]: {
              target: 'CheckValidity',
              actions: [(ctx, e) => ctx[`${id}_text`] = e.text]
            }
          }
        },
        CheckValidity: {
          on: {
            "": [
              {
                target: 'Valid',
                cond: isValid,
                
              },
              {
                target: 'Invalid',
                cond: isInvalid,
              }
            ]
          }
        },
        Invalid: {
          on: {
            [changeEventName]: {
              target: 'CheckValidity',
              actions: [(ctx, e) => ctx[`${id}_text`] = e.text]
            }
          }
        },
      }
    }
    
    return inputStateMachine
  }
  
  const fetchMachine = Machine({
    id: 'login',
    type: 'parallel',
    // initial: 'Start',
    context: {
    },
    states: {
      input: {
        on: {
          "SUBMIT": {
            actions: [(context) => console.log('submitting user credentials', context)]
          }
        }
      },
      username: {
        ...getInputMachine('username')
      },
      password: {
        ...getInputMachine('password')
      }
    }
  });