import 'dotenv/config';
import { Request, Response } from 'express';
import jwt from 'jsonwebtoken';

import { prisma } from './prisma/client';

export interface IdentityContext {
  identity?: {
    id: string;
    username: string;
  };
}

export async function getIdentityContext({
  req,
  res
}: {
  req: Request;
  res: Response;
}): Promise<IdentityContext> {
  const authHeader = req.headers.authorization;
  if (authHeader == null) return {};
  const token = authHeader.split(' ')[1];

  const accessTokenSecret = process.env.ACCESS_TOKEN_SECRET;
  if (accessTokenSecret == null) throw new Error('No `accessToken`.');

  const decoded = jwt.verify(token, accessTokenSecret) as { userId: string };
  const identity = await prisma.user.findUnique({
    where: { id: decoded.userId },
    select: {
      id: true,
      email: true,
      username: true
    }
  });
  if (identity == null) throw new Error("Couldn't find the user.");
  return { identity };
}