/* eslint-disable no-param-reassign */
import type { WebSocket, WebSocketServer } from 'ws';
import { Server } from 'node:http';

import { ServerAdapter } from './ServerAdapter';
import { WebSocketConnection } from './WebSocketConnection';
import { ServerController } from '../ServerController';
import { setCookieRequestHandler } from '../utils/setCookieRequestHandler';

export class WebSocketServerAdapter extends ServerAdapter {

  private pingInterval = 30000;

  private pingTimer!: NodeJS.Timeout;

  public constructor(public readonly wss: WebSocketServer) {
    super();
    this.init();
  }

  public close(): Promise<void> {
    return new Promise<void>((resolve, reject) => {
      const { wss } = this;
      wss.close((err) => (err ? reject(err) : resolve()));
      wss.clients.forEach((client) => client.terminate());
    });
  }

  public setServerController(controller: ServerController) {
    super.setServerController(controller);
    this.addSetHttpCookieHandler();
  }

  private init() {
    this.addSetHttpCookieHandler();
    this.listenOnConnect();
    this.initHeartbeat();
  }

  private listenOnConnect() {
    this.wss.on('connection', (ws, request) => {
      ws.on('pong', () => this.heartbeat(ws));
      const connection = new WebSocketConnection(ws, request);
      if (this.controller) {
        this.controller.onClientConnected(connection);
      } else {
        ws.close(undefined, 'The service is not ready yet.');
      }
    });
  }

  private initHeartbeat() {
    this.pingTimer = setInterval(() => this.ping(), this.pingInterval);
    this.wss.on('close', () => clearInterval(this.pingTimer));
  }

  private ping() {
    this.wss.clients.forEach((ws: WebSocket) => {
      if (ws.isAlive === false) {
        ws.terminate();
      } else {
        ws.isAlive = false;
        ws.ping();
      }
    });
  }

  private heartbeat(ws: WebSocket) {
    ws.isAlive = true;
  }

  private addSetHttpCookieHandler() {
    // eslint-disable-next-line no-underscore-dangle
    const httpServer: Server = (this.wss as any)._server;
    setCookieRequestHandler(httpServer, this.controller!);
  }

}

declare module 'ws' {
  // eslint-disable-next-line @typescript-eslint/no-shadow
  interface WebSocket {
    isAlive?: boolean;
  }
}