import { throttle } from 'lodash';

class WebSocketManager {
  constructor(url, userId) {
    this.url = url;
    this.userId = userId;
    this.ws = null;
    this.events = {};
    this.reconnectTimer = null;
    this.heartbeatTimer = null;
    this.isManualClose = false;
    this.messageQueue = [];
    this.maxQueueSize = 1;
    this.status = false;
  }

  connect() {
    if (!window.WebSocket) {
      console.error('浏览器不支持 WebSocket');
      return;
    }

    this.ws = new WebSocket(`${this.url}?userId=${this.userId}`, [], { perMessageDeflate: true });
    this.ws.binaryType = 'arraybuffer'; // 确保接收 ArrayBuffer

    this.ws.onopen = () => {
      console.log('WebSocket 已连接');
      this.status = true;
      this.startHeartbeat();
      this.processMessageQueue();
    };

    this.ws.onmessage = (event) => {
      if (this.messageQueue.length < this.maxQueueSize) {
        this.messageQueue.push(event);
        this.processMessageQueue();
      } else {
        console.warn('消息队列已满，丢弃消息');
      }
    };

    this.ws.onclose = () => {
      console.log('WebSocket 断开');
      this.status = false;
      this.stopHeartbeat();
      if (!this.isManualClose) {
        this.reconnect();
      }
    };

    this.ws.onerror = (err) => {
      console.error('WebSocket 错误:', err);
    };
  }

  async processMessageQueue() {
    if (!this.ws || this.messageQueue.length === 0) return;

    const event = this.messageQueue.shift();
    try {
      // 处理消息数据
      console.log('收到消息数据类型:', event.data.constructor.name);
      let compressedData;

      // 处理 Blob 或 ArrayBuffer
      if (event.data instanceof Blob) {
        console.log('处理 Blob 数据，大小:', event.data.size);
        compressedData = new Uint8Array(await event.data.arrayBuffer());
      } else if (event.data instanceof ArrayBuffer) {
        console.log('处理 ArrayBuffer 数据，大小:', event.data.byteLength);
        compressedData = new Uint8Array(event.data);
      } else {
        throw new Error('不支持的数据类型: ' + event.data.constructor.name);
      }

      // 使用 DecompressionStream 解压 GZIP 数据
      const decompressionStream = new DecompressionStream('gzip');
      const writer = decompressionStream.writable.getWriter();
      writer.write(compressedData);
      writer.close();

      const decompressedStream = decompressionStream.readable;
      const reader = decompressedStream.getReader();
      let decompressedData = new Uint8Array(0);

      while (true) {
        const { done, value } = await reader.read();
        if (done) break;
        const newData = new Uint8Array(decompressedData.length + value.length);
        newData.set(decompressedData);
        newData.set(value, decompressedData.length);
        decompressedData = newData;
      }

      // 将解压后的数据转换为字符串
      const textDecoder = new TextDecoder();
      const decompressedString = textDecoder.decode(decompressedData);
      console.log('解压后的数据:', JSON.parse(decompressedString));

      // 解析 JSON
      const { type, channel, payload,timestamp } = JSON.parse(decompressedString);
      console.log('后端到前端延迟:', ((new Date()).getTime() - timestamp));

      if (channel && this.events[channel]) {
        this.events[channel].forEach(callback => callback(payload));
      } else if (type && this.events[type]) {
        this.events[type].forEach(callback => callback(payload));
      }
      setTimeout(() => this.processMessageQueue(), 0);
    } catch (err) {
      console.error('WebSocket 消息解析失败:', err);
      console.error('错误堆栈:', err.stack);
      console.error('原始数据类型:', event.data.constructor.name);
      console.error('原始数据大小:', event.data instanceof Blob ? event.data.size : event.data.byteLength || '未知');
    }
  }

  on(eventName, callback) {
    if (!this.events[eventName]) {
      this.events[eventName] = [];
    }
    this.events[eventName].push(callback);
  }

  off(eventName, callback) {
    if (this.events[eventName]) {
      const index = this.events[eventName].indexOf(callback);
      if (index !== -1) {
        this.events[eventName].splice(index, 1);
      }
    }
  }

  send(payload) {
    if (this.ws && this.ws.readyState === 1) {
      this.ws.send(JSON.stringify(payload));
    } else {
      console.warn('WebSocket 未连接，消息发送失败');
    }
  }

  close() {
    this.isManualClose = true;
    this.status = false;
    this.stopHeartbeat();
    if (this.ws) {
      this.ws.close();
    }
  }

  reconnect() {
    clearTimeout(this.reconnectTimer);
    this.reconnectTimer = setTimeout(() => {
      console.log('尝试重新连接 WebSocket...');
      this.connect();
    }, 5000);
  }

  startHeartbeat() {
    this.heartbeatTimer = setInterval(() => {
      this.send({ type: 'heartbeat' });
    }, 30000);
  }

  stopHeartbeat() {
    clearInterval(this.heartbeatTimer);
  }

  status() {
    return this.status;
  }
}

export default {
  install(app, options) {
    const { url, userId } = options;
    const wsManager = new WebSocketManager(url, userId);
    wsManager.connect();
    app.config.globalProperties.$ws = wsManager;
    app.provide('ws', wsManager);
  }
};