import { BcryptCrypto, Crypto } from "./crypto.ts";
import { Database } from "./database.ts";
import { Err, Ok, Result } from "./utils.ts";

export type LoginReq = {
    username: string;
    password: string;
};

export type LoginRes = {
    sessionId: number;
};

export type LoginError =
    | "internal"
    | "wrong username/password"
    | "account banned";

export class Sessions {
    public constructor(
        private db: Database,
        private crypto: Crypto = new BcryptCrypto(),
    ) {}

    public async login(req: LoginReq): Promise<Result<LoginRes, LoginError>> {
        const findUserResult = await this.db.userWithUsername(req.username);
        if (!findUserResult.ok) {
            return Err("internal");
        }
        if (!findUserResult.value.some) {
            return Err("wrong username/password");
        }
        const user = findUserResult.value.value;
        if (!await this.crypto.compare(req.password, user.passwordHash)) {
            return Err("wrong username/password");
        }
        const session = await this.db.createSession({
            userId: user.id,
        });
        if (!session.ok) {
            return Err("internal");
        }
        return Ok({
            sessionId: session.value.id,
        });
    }
}