import { ApolloServer } from '@apollo/server';
import { expressMiddleware } from '@apollo/server/express4';
import { ApolloServerPluginDrainHttpServer } from '@apollo/server/plugin/drainHttpServer';
import cors from 'cors';
import 'dotenv/config';
import express, { Request, Response } from 'express';
import fs from 'fs';
import http from 'http';
import jwt from 'jsonwebtoken';
import path from 'path';
import ViteExpress from 'vite-express';

import { Mutation, Query } from './graphql/graphql';
import { prisma } from './prisma/client';

const __dirname = import.meta.dirname;
const HOST = process.env.VITE_HOST || 'localhost';
const PORT = parseInt(process.env.VITE_PORT || '3000');
const MOTD = `\n\n\n\x1b[35m-server is listening at...-\x1b[0m\n\nhttp://${HOST}:${PORT}\nhttp://localhost:${PORT}\n\n\n`;

const app = express();
const server = http.createServer(app);

const typeDefs = fs.readFileSync(path.join(__dirname, 'graphql', 'schema.graphql'), 'utf8');

const resolvers = {
  Query,
  Mutation
  // Subscription,
};

interface IdentityContext {
  authScope?: String;
}

const apollo = new ApolloServer<IdentityContext>({
  typeDefs,
  resolvers,
  plugins: [ApolloServerPluginDrainHttpServer({ httpServer: server })]
});

await apollo.start();

app.use(
  '/graphql',
  cors<cors.CorsRequest>(),
  express.json(),
  expressMiddleware(apollo, {
    context: getUser
  })
);

await new Promise<void>(resolve => server.listen({ hostname: HOST, port: PORT }, resolve));

process.stdout.write(MOTD);

ViteExpress.bind(app, server);

async function getUser({ req, res }: { req: Request; res: Response }) {
  const authHeader = req.headers.authorization;
  if (!authHeader) return { identity: null };
  const token = authHeader.split(' ')[1];

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

  const decoded = jwt.verify(token, accessTokenSecret) as { userId: string };
  const identity = await prisma.user.findUnique({ where: { id: decoded.userId } });
  return { identity };
}