text: // import { nextTick } from 'vue'
  import Main from './main.vue'
  import { PopupManager } from 'element-ui/src/utils/popup'
  import { isVNode } from 'element-ui/src/utils/vdom'
  let MessageConstructor = {extends: Main}
  
  let instance
  let instances = []
  let seed = 1
  
  const Message = function(options) {
    // if (Vue.prototype.$isServer) return
    options = options || {}
    if (typeof options === 'string') {
      options = {
        message: options
      }
    }
    let userOnClose = options.onClose
    let id = 'message_' + seed++
  
    options.onClose = function() {
      Message.close(id, userOnClose)
    }
    instance = new MessageConstructor({
      data: options
    })
    instance.id = id
    if (isVNode(instance.message)) {
      instance.$slots.default = [instance.message]
      instance.message = null
    }
    instance.$mount()
    document.body.appendChild(instance.$el)
    let verticalOffset = options.offset || 20
    instances.forEach(item => {
      verticalOffset += item.$el.offsetHeight + 16
    })
    instance.verticalOffset = verticalOffset
    instance.visible = true
    instance.$el.style.zIndex = PopupManager.nextZIndex()
    instances.push(instance)
    return instance
  };
  
  ['success', 'warning', 'info', 'error'].forEach(type => {
    Message[type] = options => {
      if (typeof options === 'string') {
        options = {
          message: options
        }
      }
      options.type = type
      return Message(options)
    }
  })
  
  Message.close = function(id, userOnClose) {
    let len = instances.length
    let index = -1
    let removedHeight
    for (let i = 0; i < len; i++) {
      if (id === instances[i].id) {
        removedHeight = instances[i].$el.offsetHeight
        index = i
        if (typeof userOnClose === 'function') {
          userOnClose(instances[i])
        }
        instances.splice(i, 1)
        break
      }
    }
    if (len <= 1 || index === -1 || index > instances.length - 1) return
    for (let i = index; i < len - 1 ; i++) {
      let dom = instances[i].$el
      dom.style['top'] =
        parseInt(dom.style['top'], 10) - removedHeight - 16 + 'px'
    }
  }
  
  Message.closeAll = function() {
    for (let i = instances.length - 1; i >= 0; i--) {
      instances[i].close()
    }
  }
  
  export default Message
  