/**
 * Copyright (C) 2019-2021 Carl Kittelberger <icedream@icedream.pw>
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import { GetServerSideProps } from 'next';
import { create } from 'xmlbuilder2';
import { getIndex, getVideos } from '../util/api';
import sanitizeTitle from '../util/sanitizeTitle';

const urlsetNamespace = 'http://www.sitemaps.org/schemas/sitemap/0.9';

export const getServerSideProps: GetServerSideProps = async (ctx) => {
  const { req, res } = ctx;

  const { ids } = await getIndex();

  const basePath = `https://${req.headers.host}`;

  const url = [
    {
      loc: basePath,
    },
  ];

  const results = await Promise.all(
    ids.map(async ({ id }) => {
      const vodInfo = await getVideos(id);
      const { lastUpdatedAt, videos } = vodInfo;
      return [
        {
          loc: `${basePath}/${id}`,
          lastmod: lastUpdatedAt,
        },
        ...videos.map(({
          title,
        }) => ({
          loc: `${basePath}/${id}/${sanitizeTitle(title)}`,
          lastmod: lastUpdatedAt,
        })),
      ];
    }, url),
  );

  url.push(
    ...(results
      .reduce((old, current) => [...old, ...current], [])),
  );

  const root = create({ version: '1.0' })
    .ele(urlsetNamespace, 'urlset')
    .ele({
      url,
    })
    .doc();

  // convert the XML tree to string
  const xml = root.end({ prettyPrint: true });
  res.setHeader('Content-Type', 'text/xml');
  res.write(xml);
  res.end();
  return {
    props: {},
  };
};

export default () => {};