import {getToken} from 'next-auth/jwt';
import {NextRequest, NextResponse} from 'next/server';
import {
  ProfileDocument,
  Enum_Userspermissionsuser_Lang as SupportedLocales,
} from './generated/graphql';
import {initializeApollo} from './lib/apolloClient';
import {getCookie} from './lib/cookies';

const PUBLIC_FILE = /\.(.*)$/;
const DEFAULT_LOCALE = process.env.DEFAULT_LOCALE || 'share';

export async function middleware(req: NextRequest) {
  if (
    req.nextUrl.pathname.startsWith('/_next') ||
    req.nextUrl.pathname.includes('/api/') ||
    req.nextUrl.pathname === '/graphql' ||
    PUBLIC_FILE.test(req.nextUrl.pathname)
  ) {
    return;
  }

  if (req.nextUrl.locale === DEFAULT_LOCALE) {
    const registeredUserLanguage = await getRegisteredUserLanguage(req);
    const NEXT_LOCALE = getCookie('NEXT_LOCALE', req.headers.get('cookie'));
    const browserPreferredSupportedLanguage =
      getBrowserPreferredSupportedLanguage(req);

    const locale =
      registeredUserLanguage ||
      NEXT_LOCALE ||
      browserPreferredSupportedLanguage ||
      'fr';

    return NextResponse.redirect(
      new URL(`/${locale}${req.nextUrl.pathname}`, req.url)
    );
  }
}

const getRegisteredUserLanguage = async req => {
  const token = await getToken({
    req,
    secret: process.env.NEXTAUTH_SECRET,
  });

  if (token?.jwt) {
    const {STRAPI_URL = 'http://localhost:1337'} = process.env;
    const apolloClient = initializeApollo(
      `${STRAPI_URL}/graphql`,
      token.jwt as string
    );

    const {data} = await apolloClient.query({
      query: ProfileDocument,
    });

    return data?.me?.profile?.lang;
  }
};

const getBrowserPreferredSupportedLanguage = req => {
  const browserAcceptedLanguages = req.headers
    .get('accept-language')
    ?.split(',');
  let browserPreferredSupportedLanguage = null;
  browserAcceptedLanguages?.every(locale => {
    const lang = locale.split('-')?.[0].toLowerCase();

    if (Object.keys(SupportedLocales).includes(lang)) {
      browserPreferredSupportedLanguage = lang;
    } else {
      return false;
    }
  });
  return browserPreferredSupportedLanguage;
};