//in webpack environment:
import vuejsStorage from 'vuejs-storage'
//in browser script tag:
const vuejsStorage = window.vuejsStorage

Vue.use(vuejsStorage)

//vue example
new Vue({
  //...
  data: {
    count: 0,
    text: ''
  },
  storage: {
    keys: ['count'],
    //keep data.count in localStorage
    namespace: 'my-namespace'
  }
})

//vuex example
const store = new Vuex.Store({
  //state...
  state: {
    count: 0
  },
  mutations: {
    increment(state) {
      state.count++
    }
  },
  plugins: [
    vuejsStorage({
      keys: ['count'],
      //keep state.count in localStorage
      namespace: 'my-namespace',
      driver: vuejsStorage.drivers.sessionStorage
      //if you want to use sessionStorage instead of localStorage
    })
  ]
})

data: {
  a: {
    b: 1,
    c: 2
  }
},
storage: {
  namespace: 'test',
  keys: ['a.b']
  //only keep a.b in localStorage
}

state: {
  a: 1
},
modules: {
  moduleA: {
    state: {
      a: 2
    }
  }
},
plugins: [
  vuejsStorage({
    namespace: 'test',
    keys: ['moduleA','a']
    // keep both root's state.a & moduleA's state
  })
]

data: {
  a: 1,
  b: 2
},
storage: [
  {
    namespace: 'test',
    keys: ['a']
  },
  {
    namespace: 'test',
    keys: ['b'],
    driver: vuejsStorage.drivers.sessionStorage
  }
]

Vue.use(vuejsStorage)

const vuexplugin = vuejsStorage(/* option object*/)

{
  keys: [], //array of string
  /*
  this option is different when use in vue and vuex
  when used in Vue constructor option, keys means which data should be keep in localStorage
  when used in Vuex plugin, keys mean which state should be keep in localStorage
  */
  driver: vuejsStorage.drivers.sessionStorage, //any object has 'set','get','has' api, default: vuejsStorage.drivers.localStorage
  namespace: 'ns', //a string, REQUIRED
  merge: _assign //a function to merge object like Object.assign, default: internal implementation(src/assign.ts)
}