import { Request, Response, NextFunction } from "express";

export interface AuthenticatedUser {
  userId: string;
}

export interface AuthenticatedRequest extends Request {
  user?: AuthenticatedUser;
}

export function authenticate(
  req: AuthenticatedRequest,
  res: Response,
  next: NextFunction,
): void {
  const userId = req.headers["x-user-id"];

  if (!userId || typeof userId !== "string") {
    res.status(401).json({ error: "Unauthorized" });
    return;
  }

  req.user = { userId };
  next();
}