import { Session } from '@generated/types';
import 'dotenv/config';
import { Request, Response } from 'express';
import { GraphQLError } from 'graphql';
import jwt from 'jsonwebtoken';
import { config } from './main';
import { prisma } from './prisma/client';

export interface IdentityContext {
  req: Request;
  res: Response;
  identity?: {
    id: string;
    email: string;
    username: string;
  };
}

export async function getIdentityContext({
  req,
  res
}: {
  req: Request;
  res: Response;
}): Promise<IdentityContext> {
  try {
    const authHeaders = req.headers.authorization;
    if (authHeaders == null) return { req, res };

    const session: Session = JSON.parse(authHeaders);
    const { accessToken } = session;

    const decoded = jwt.verify(accessToken, config.accessToken.secret) as {
      userId: string;
      iat: number;
      exp: number;
    };

    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 { req, res, identity };
  } catch (error) {
    if (error instanceof Error)
      throw new GraphQLError(error.message, {
        extensions: {
          code: 'UNAUTHENTICATED',
          http: { status: 401 }
        }
      });
    throw new GraphQLError(typeof error === 'string' ? error : 'Unknown error', {
      extensions: {
        code: 'UNAUTHENTICATED',
        http: { status: 401 }
      }
    });
  }
}