server/pusher/src/Services/JWTTokenManager.ts

import { ADMIN_API_URL, ALLOW_ARTILLERY, SECRET_KEY } from "../Enum/EnvironmentVariable";
import { uuid } from "uuidv4";
import Jwt from "jsonwebtoken";
import { TokenInterface } from "../Controller/AuthenticateController";
import { adminApi, AdminBannedData } from "../Services/AdminApi";

class JWTTokenManager {
    public createJWTToken(userUuid: string) {
        return Jwt.sign({ userUuid: userUuid }, SECRET_KEY, { expiresIn: "200d" }); //todo: add a mechanic to refresh or recreate token
    }

    public async getUserUuidFromToken(token: unknown, ipAddress?: string, roomUrl?: string): Promise<string> {
        if (!token) {
            throw new Error("An authentication error happened, a user tried to connect without a token.");
        }
        if (typeof token !== "string") {
            throw new Error("Token is expected to be a string");
        }

        if (token === "test") {
            if (ALLOW_ARTILLERY) {
                return uuid();
            } else {
                throw new Error(
                    "In order to perform a load-testing test on this environment, you must set the ALLOW_ARTILLERY environment variable to 'true'"
                );
            }
        }

        return new Promise<string>((resolve, reject) => {
            Jwt.verify(token, SECRET_KEY, {}, (err, tokenDecoded) => {
                const tokenInterface = tokenDecoded as TokenInterface;
                if (err) {
                    console.error("An authentication error happened, invalid JsonWebToken.", err);
                    reject(new Error("An authentication error happened, invalid JsonWebToken. " + err.message));
                    return;
                }
                if (tokenDecoded === undefined) {
                    console.error("Empty token found.");
                    reject(new Error("Empty token found."));
                    return;
                }

                //verify token
                if (!this.isValidToken(tokenInterface)) {
                    reject(new Error("Authentication error, invalid token structure."));
                    return;
                }

                if (ADMIN_API_URL) {
                    //verify user in admin
                    let promise = new Promise((resolve) => resolve());
                    if (ipAddress && roomUrl) {
                        promise = this.verifyBanUser(tokenInterface.userUuid, ipAddress, roomUrl);
                    }
                    promise
                        .then(() => {
                            adminApi
                                .fetchCheckUserByToken(tokenInterface.userUuid)
                                .then(() => {
                                    resolve(tokenInterface.userUuid);
                                })
                                .catch((err) => {
                                    //anonymous user
                                    if (err.response && err.response.status && err.response.status === 404) {
                                        resolve(tokenInterface.userUuid);
                                        return;
                                    }
                                    reject(err);
                                });
                        })
                        .catch((err) => {
                            reject(err);
                        });
                } else {
                    resolve(tokenInterface.userUuid);
                }
            });
        });
    }

    private verifyBanUser(userUuid: string, ipAddress: string, roomUrl: string): Promise<AdminBannedData> {
        return adminApi
            .verifyBanUser(userUuid, ipAddress, roomUrl)
            .then((data: AdminBannedData) => {
                if (data && data.is_banned) {
                    throw new Error("User was banned");
                }
                return data;
            })
            .catch((err) => {
                throw err;
            });
    }

    private isValidToken(token: object): token is TokenInterface {
        return !(typeof (token as TokenInterface).userUuid !== "string");
    }
}

export const jwtTokenManager = new JWTTokenManager();