import LoginActions from '../LoginRedux'
import jwtDecode from 'jwt-decode'
import moment from 'moment'
import {startsWith} from 'lodash'
import { Actions as NavigationActions } from 'react-native-router-flux'

let buffer = []

const isValidScreen = () => {
  if (NavigationActions.currentScene === '') return false

  const notValidScreens = [
    'loginScreen',
    'signupScreen'
  ]
  return !notValidScreens.find(screen => screen === NavigationActions.currentScene)
}

const isExpired = (token) => {
  const expiration = jwtDecode(token).exp
  return moment.unix(expiration) - moment(Date.now()) < 30
}

const authMiddleware = store => next => action => {
  const state = store.getState()
  let isTokenExpired = false

  if (action.type === 'REFRESH_TOKEN_REQUEST') {
    return next(action)
  }

  if (action.type === 'REFRESH_TOKEN_SUCCESS') {
    next(action)

    if (buffer.length > 0) {
      buffer.forEach(action => store.dispatch(action))
      buffer = []
    }
  }

  if (!startsWith(action.type, 'REFRESH_TOKEN')) {
    if (state && isValidScreen()) {
      isTokenExpired = isExpired(state.login.token)

      if (state.login.token && isTokenExpired) {
        if (!state.login.refreshingToken && buffer.length <= 0) {
          store.dispatch(LoginActions.refreshTokenRequest(state.login.refreshToken))
        }

        buffer.push(action)
      }
    }
  }

  if (!isTokenExpired && action.type !== 'REFRESH_TOKEN_SUCCESS') {
    return next(action)
  }
}

export default authMiddleware