// Adapted from https://gist.github.com/joranquinten/78f3e288274a3c9405a499b8a8c46e35
import * as fs from 'fs';
import { execSync } from 'child_process';
import { createRequire } from 'module';
import directory from '../src/directory/directory.mjs';

const require = createRequire(import.meta.url);
const generatePathMap = require('../generatePathMap.cjs');

const formatDate = (date) => `${date.toISOString().split('.')[0]}+0:00`;
const getPriority = (_) => 0.5;

const lastModifiedCache = {};
const lastModified = (path) => {
  if (path == '/ChooseFilterPage') {
    path = `./src/pages${path}.tsx`;
  } else if (path == '/') {
    path = `./src/pages/index.tsx`;
  } else if (path == '/404') {
    path = `./src/pages/404.tsx`;
  } else if (path == '/console') {
    path = `./src/pages/console/index.mdx`;
  } else if (path == '/cli') {
    path = `./src/pages/cli/index.mdx`;
  } else if (path == '/cli/function') {
    path = `./src/pages/cli/function/index.mdx`;
  } else {
    path = `./src/pages${path}.mdx`;
  }
  if (fs.existsSync(path)) {
    if (path in lastModifiedCache) {
      return lastModifiedCache[path];
    }
    return (lastModifiedCache[path] = execSync(
      `git log -1 --pretty="format:%cI" ${path}`
    ));
  }
  console.log(`${path} doesn't exist`);
  return formatDate(new Date());
};

const xmlHeader = `<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">`;
const xmlUrlWrapper = (nodes) => `${xmlHeader}
  ${nodes}
</urlset>`;

const domain = 'https://docs.amplify.aws';
const xmlUrlNode = (pageUrl, pagePath) => {
  const lastmod = lastModified(pagePath);
  const url = `${pageUrl}${pageUrl === '/' ? '' : '/'}`;
  const loc = `${domain}${url}`;
  const priority = getPriority(url);
  return `
<url>
  <loc>${loc}</loc>
  <lastmod>${lastmod}</lastmod>
  <changefreq>hourly</changefreq>
  <priority>${priority}</priority>
</url>`;
};

const writeSitemap = async () => {
  const sitemapPath = './public/sitemap.xml';
  const pathmap = generatePathMap(directory, undefined, true);
  let xmlUrlNodes = '';
  for (const pageUrl in pathmap) {
    const pagePath = pathmap[pageUrl].page;
    xmlUrlNodes += xmlUrlNode(pageUrl, pagePath);
  }
  const sitemap = `${xmlUrlWrapper(xmlUrlNodes)}`;
  fs.writeFileSync(sitemapPath, sitemap);
  console.log(`sitemap written to ${sitemapPath}`);
};

const writeRobots = () => {
  let robotsContent = `User-agent: *\nDisallow:\n`;
  if (typeof process.env.ALLOW_ROBOTS === 'undefined') {
    robotsContent = `User-agent: *\nDisallow: /\n`;
  }

  const robotsPath = './public/robots.txt';
  fs.writeFileSync(robotsPath, robotsContent);
  console.log(`robots.txt written to ${robotsPath}`);
};

writeSitemap();
writeRobots();