export default class websocket {
  constructor(url, options) {
    this.instance = null
    this.token = null
    this.isConnected = false
    this.url = url
    this.options = options || this.defaultOptions()
    if (this.options) {
      this.reconnectEnabled = options.reconnectEnabled || false
      if (this.reconnectEnabled) {
        this.reconnectInterval = options.reconnectInterval
      }
      // Token
      // this.token = options?.token || null
    }
    // These methods should be defined by components
    this.onOpen = null
    this.onMessage = null
    this.onClose = null
    this.onError = null
  }

  defaultOptions() {
    return {
      reconnectEnabled: false,
      reconnectInterval: 0,
      token: null,
    }
  }

  connect() {
    const token = this.token || null
    let url = this.url
    if (token !== null) {
      url += `?token=${token}`
    }
    this.instance = new WebSocket(url)

    // Socket event listeners
    // Each event handler also calls the corresponding class method,
    // which can be defined by the component
    this.instance.onopen = () => {
      this.isConnected = true
      console.log('链接成功')
      if (typeof this.onOpen === 'function') {
        this.onOpen()
      }
    }
    this.instance.onmessage = (msg) => {
      if (typeof this.onMessage === 'function') {
        this.onMessage(msg)
      }
    }
    this.instance.onclose = (evt) => {
      this.isConnected = false
      if (typeof this.onClose === 'function') {
        this.onClose(evt)
      }
      if (this.reconnectEnabled) {
        this.reconnect()
      }
    }
    this.instance.onerror = (evt) => {
      if (typeof this.onError === 'function') {
        this.onError(evt)
      }
    }
  }

  disconnect() {
    try {
      this.instance.close()
    }
    catch (e) {
      console.warn(`${e} ${this.instance}`)
    }
    delete this.instance
  }

  reconnect() {
    try {
      this.instance.close()
    }
    catch (e) {
      console.warn(`${e} ${this.instance}`)
    }
    delete this.instance
    setTimeout(() => {
      this.connect()
    }, this.reconnectInterval)
  }

  sendObj(data) {
    if (this.instance.readyState === this.instance.OPEN) {
      // 若是ws开启状态
      this.instance.send(JSON.stringify(data))
    }
    else if (this.instance.readyState === this.instance.CONNECTING) {
      // 若是 正在开启状态，则等待1s后重新调用
      setTimeout(() => {
        this.sendObj(data)
      }, 1000)
    }
    else {
      // 若未开启 ，则等待1s后重新调用
      setTimeout(() => {
        this.sendObj(data)
      }, 1000)
    }
  }

  removeListeners() {
    // removeListeners
    this.onOpen = null
    this.onMessage = null
    this.onClose = null
    this.onError = null
  }
}