// Available variables:
  // - Machine
  // - interpret
  // - assign
  // - send
  // - sendParent
  // - spawn
  // - raise
  // - actions
  // - XState (all XState exports)
  
  const statusEquals = status => context => context?.error?.response?.status === status;
  
  const fetchMachine = Machine({
    id: 'fetch',
    initial: 'idle',
    context: {
      retries: 0,
      data: null,
      error: null,
      isValidating: false,
    },
    states: {
      idle: {
        on: {
          REQUEST: 'loading'
        },
      },
      loading: {
        invoke: {
          src: 'load_user',
          onDone: {
            target: 'fulfilled',
            actions: assign({
              data: (_, event) => event.data,
            }),
          },
          onError: {
            target: 'rejected',
            actions: assign({
              error: (_, event) => event.error,
            })
          }
        }
      },
      fulfilled: {
        type: 'final',
        entry: 'onComplete',
        on: {
          RELOAD: 'loading',
        }
      },
      rejected: {
        meta: 'Handles API rejections',
        initial: 'unknown',
        states: {
          unknown: {
            on: {
              '': [
                { target: 'bad request', cond: '400' },
                { target: 'unauthorized', cond: '401' },
                { target: 'forbidden', cond: '403' }
              ]
            }
          },
          'bad request': {
            type: 'final',
          },
          'unauthorized': {
            type: 'final',
          },
          'forbidden': {
            type: 'final',
          }
        },
        on: {
          RETRY: 'loading',
          actions: assign({
            retries: (context, event) => {
              context.retries + 1;
            }
          })
        }
      },
    }
  }, {
    guards: {
      400: statusEquals(400),
      401: statusEquals(401),
      403: statusEquals(403),
    }
  });