const { createStore, applyMiddleware } = require('redux');

const initialState = { count: 0 };
const incrementReducer = (state = initialState, action) => {
  switch (action.type) {
    case 'INC': return { count: Math.min(10, state.count + 1) };
    case 'DEC': return { count: state.count - 1 };
    case 'RND': return { count: state.count + action.amt };
    default: return state;
  }
};

const uselessMW = store => next => (action) => {
  console.log(action);
  next(action);
};

const blockDec = store => next => (action) => {
  if (action.type !== 'DEC') {
    next(action);
  }
};

const delayAction = store => next => (action) => {
  setTimeout(() => {
    next(action);
  }, 1500);
};

const randomRequest = () => {
  const randomDelayTimeout = (Math.random() * 2000) + 1000;
  const randomDelayPromise = new Promise((resolve) => {
    setTimeout(resolve, randomDelayTimeout);
  });
  return randomDelayPromise
    .then(() => Math.floor(Math.random() * 5) - 2);
};
const makeRandomRequestMW = store => next => (action) => {
  if (action.type === 'REQ') {
    randomRequest()
      .then((amt) => {
        store.dispatch({ type: 'RND', amt });
      });
  } else {
    next(action);
  }
};

// const getUsersMW = store => next => (action) => {
//   if (action.type === 'FETCH_USERS') {
//     store.dispatch({ type: 'FETCH_USERS_PENDING' });
//     getUsersFromAPI()
//       .then((users) => {
//         store.dispatch({ type: 'FETCH_USERS_SUCCESS', users });
//       }, (error) => {
//         store.dispatch({ type: 'FETCH_USERS_ERROR', error });
//       });
//   } else {
//     next(action);
//   }
// };

const incrementAction = { type: 'INC' };
const decrementAction = { type: 'DEC' };
const requestRandomIncAction = { type: 'REQ' };

const store = createStore(incrementReducer, applyMiddleware(uselessMW, makeRandomRequestMW));
console.log(store.getState());
const unsubscribe = store.subscribe(() => {
  console.log(store.getState());
});

setInterval(() => {
  store.dispatch(requestRandomIncAction);
}, 1500);

// setInterval(() => {
//   store.dispatch(incrementAction);
// }, 2000);

// setInterval(() => {
//   store.dispatch(decrementAction);
// }, 3400);


// setTimeout(unsubscribe, 10000);