class WebsocketStream {
  static EXPECTED_PONG_BACK = 10000;
  static KEEP_ALIVE_CHECK_INTERVAL = 5000;
  pingTimeout = null;
  keepAliveInterval = null;
  provider;
  providerWss;

  constructor() {
    this.provider = new ethers.providers.JsonRpcProvider(
      CONFIG.rpc_arb_http
    );
    this.providerWss = new ethers.providers.WebSocketProvider(
      CONFIG.rpc_eth_wss
    );
  }

  async init() {
    this.providerWss._websocket.on("open", async () => {
      this.keepAliveInterval = setInterval(() => {
        this.providerWss._websocket.ping();
        this.pingTimeout = setTimeout(() => {
          this.providerWss._websocket.terminate();
        }, WebsocketStream.EXPECTED_PONG_BACK);
      }, WebsocketStream.KEEP_ALIVE_CHECK_INTERVAL);

      this.providerWss.on("block", async (blockNum) => {
        console.log(blockNum);
      });
    });

    this.providerWss._websocket.on("close", (code) => {
      console.log(
        `Connection lost with code ${code}! Attempting reconnect in 1s...`
      );
      this.restart();
    });

    this.providerWss._websocket.on("pong", () => {
      // console.log(`Connection is alive`);
      clearInterval(this.pingTimeout);
    });

    this.providerWss._websocket.on("error", () => {
      console.error(`Unable to connect. Reconnect...`);
      this.restart();
    });
  }

  destroy() {
    this.providerWss._websocket.terminate();
    clearInterval(this.keepAliveInterval);
    clearTimeout(this.pingTimeout);
  }

  restart() {
    this.destroy();
    new WebsocketStream().init();
  }
}