// src/Auth/AuthService.js

import auth0 from 'auth0-js'
import { AUTH_CONFIG } from './auth0-variables'
import EventEmitter from 'eventemitter3'
import router from './../router'

export default class AuthService {

  constructor () {
    this.login = this.login.bind(this)
    this.setSession = this.setSession.bind(this)
    this.logout = this.logout.bind(this)
    this.isAuthenticated = this.isAuthenticated.bind(this)
  }

  auth0 = new auth0.WebAuth({
    domain: 'YOUR_AUTH0_DOMAIN',
    clientID: 'YOUR_CLIENT_ID',
    redirectUri: 'http://localhost:3000/callback',
    responseType: 'token id_token',
    scope: 'openid'
  })

  login () {
    this.auth0.authorize()
  }
}

// src/Auth/AuthService.js

import auth0 from 'auth0-js'
import EventEmitter from 'EventEmitter'
import router from './../router'

export default class AuthService {

  authenticated = this.isAuthenticated()
  authNotifier = new EventEmitter()

  constructor () {
    this.login = this.login.bind(this)
    this.setSession = this.setSession.bind(this)
    this.logout = this.logout.bind(this)
    this.isAuthenticated = this.isAuthenticated.bind(this)
  }

  // ...
  handleAuthentication () {
    this.auth0.parseHash((err, authResult) => {
      if (authResult && authResult.accessToken && authResult.idToken) {
        this.setSession(authResult)
        router.replace('home')
      } else if (err) {
        router.replace('home')
        console.log(err)
      }
    })
  }

  setSession (authResult) {
    // Set the time that the Access Token will expire at
    let expiresAt = JSON.stringify(
      authResult.expiresIn * 1000 + new Date().getTime()
    )
    localStorage.setItem('access_token', authResult.accessToken)
    localStorage.setItem('id_token', authResult.idToken)
    localStorage.setItem('expires_at', expiresAt)
    this.authNotifier.emit('authChange', { authenticated: true })
  }

  logout () {
    // Clear Access Token and ID Token from local storage
    localStorage.removeItem('access_token')
    localStorage.removeItem('id_token')
    localStorage.removeItem('expires_at')
    this.userProfile = null
    this.authNotifier.emit('authChange', false)
    // navigate to the home route
    router.replace('home')
  }

  isAuthenticated () {
    // Check whether the current time is past the
    // Access Token's expiry time
    let expiresAt = JSON.parse(localStorage.getItem('expires_at'))
    return new Date().getTime() < expiresAt
  }
}

// src/components/Callback.vue

<template>
  <div class="spinner">
    <img src="../assets/loading.svg" alt="loading"/>
  </div>
</template>

<script>
  export default {
    name: 'callback',
    props: ['auth'],
    data () {
      this.auth.handleAuthentication()
      return {}
    }
  }
</script>

<style>
  .spinner {
    position: absolute;
    display: flex;
    justify-content: center;
    height: 100vh;
    width: 100vw;
    background-color: white;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
  }
</style>