<template>
  <div></div>
</template>
<script setup lang="ts" name="global-websocket">
import { ElNotification } from 'element-plus';
import { Session } from '/@/utils/storage';

const emit = defineEmits(['rollback']);

const props = defineProps({
  uri: {
    type: String,
  },
});

const state = reactive({
  webSocket: ref(), // webSocket实例
  lockReconnect: false, // 重连锁，避免多次重连
  maxReconnect: 6, // 最大重连次数， -1 标识无限重连
  reconnectTime: 0, // 重连尝试次数
  heartbeat: {
    interval: 30 * 1000, // 心跳间隔时间
    timeout: 10 * 1000, // 响应超时时间
    pingTimeoutObj: ref(), // 延时发送心跳的定时器
    pongTimeoutObj: ref(), // 接收心跳响应的定时器
    pingMessage: JSON.stringify({ type: 'ping' }), // 心跳请求信息
  },
});

const token = computed(() => {
  return Session.getToken();
});

const tenant = computed(() => {
  return Session.getTenant();
});

onMounted(() => {
  initWebSocket();
});

onUnmounted(() => {
  state.webSocket.close();
  clearTimeoutObj(state.heartbeat);
});

const initWebSocket = () => {
  // ws地址
  let host = window.location.host;
  //  baseURL
  let baseURL = import.meta.env.VITE_API_URL;
  let wsUri = `ws://${host}${baseURL}${props.uri}?access_token=${token.value}&TENANT-ID=${tenant.value}`;
  // 建立连接
  state.webSocket = new WebSocket(wsUri);
  // 连接成功
  state.webSocket.onopen = onOpen;
  // 连接错误
  state.webSocket.onerror = onError;
  // 接收信息
  state.webSocket.onmessage = onMessage;
  // 连接关闭
  state.webSocket.onclose = onClose;
};

const reconnect = () => {
  if (!token) {
    return;
  }
  if (state.lockReconnect || (state.maxReconnect !== -1 && state.reconnectTime > state.maxReconnect)) {
    return;
  }
  state.lockReconnect = true;
  setTimeout(() => {
    state.reconnectTime++;
    // 建立新连接
    initWebSocket();
    state.lockReconnect = false;
  }, 5000);
};
/**
 * 清空定时器
 */
const clearTimeoutObj = (heartbeat: any) => {
  heartbeat.pingTimeoutObj && clearTimeout(heartbeat.pingTimeoutObj);
  heartbeat.pongTimeoutObj && clearTimeout(heartbeat.pongTimeoutObj);
};
/**
 * 开启心跳
 */
const startHeartbeat = () => {
  const webSocket = state.webSocket;
  const heartbeat = state.heartbeat;
  // 清空定时器
  clearTimeoutObj(heartbeat);
  // 延时发送下一次心跳
  heartbeat.pingTimeoutObj = setTimeout(() => {
    // 如果连接正常
    if (webSocket.readyState === 1) {
      //这里发送一个心跳，后端收到后，返回一个心跳消息，
      webSocket.send(heartbeat.pingMessage);
      // 心跳发送后，如果服务器超时未响应则断开，如果响应了会被重置心跳定时器
      heartbeat.pongTimeoutObj = setTimeout(() => {
        webSocket.close();
      }, heartbeat.timeout);
    } else {
      // 否则重连
      reconnect();
    }
  }, heartbeat.interval);
};

/**
 * 连接成功事件
 */
const onOpen = () => {
  //开启心跳
  startHeartbeat();
  state.reconnectTime = 0;
};
/**
 * 连接失败事件
 * @param e
 */
const onError = () => {
  //重连
  reconnect();
};

/**
 * 连接关闭事件
 * @param e
 */
const onClose = () => {
  //重连
  reconnect();
};
/**
 * 接收服务器推送的信息
 * @param msgEvent
 */
const onMessage = (msgEvent: any) => {
  //收到服务器信息，心跳重置并发送
  startHeartbeat();
  const text = msgEvent.data;

  if (text.indexOf('pong') > 0) {
    return;
  }

  ElNotification.warning({
    title: '消息提醒',
    dangerouslyUseHTMLString: true,
    message: text + '请及时处理',
    offset: 60,
  });

  emit('rollback', text);
};
</script>
