import config from "config";
import cookie from "cookie";
import cookieParser from "cookie-parser";
import {Request} from "express";
import {Session} from "express-session";
import {IncomingMessage} from "http";
import {WebSocket} from "ws";

import Application from "./Application.js";
import RedisComponent from "./components/RedisComponent.js";
import {logger} from "./Logger.js";
import WebSocketListener from "./WebSocketListener.js";

export default abstract class SessionWebSocketListener<A extends Application> extends WebSocketListener<A> {

    public async handle(socket: WebSocket, request: IncomingMessage): Promise<void> {
        socket.once('message', (data, isBinary) => {
            if (isBinary) return socket.close(1003);

            const cookies = cookie.parse(data.toString());
            const sid = cookieParser.signedCookie(cookies['connect.sid'], config.get('session.secret'));

            if (!sid) {
                socket.close(1002, 'Could not decrypt provided session cookie.');
                return;
            }

            const store = this.getApp().as(RedisComponent).getStore();
            store.get(sid, (err, session) => {
                if (err || !session) {
                    logger.error(err, 'Error while initializing session in websocket for sid ' + sid);
                    socket.close(1011);
                    return;
                }

                session.id = sid;

                store.createSession(<Request>request, session);
                this.handleSessionSocket(socket, request, session as Session).catch(err => {
                    logger.error(err, 'Error in websocket listener.');
                });
            });
        });
    }

    protected abstract handleSessionSocket(
        socket: WebSocket,
        request: IncomingMessage,
        session: Session,
    ): Promise<void>;
}