import { createServer } from 'node:http';
import { readFile, stat } from 'node:fs/promises';
import { dirname, extname, join, resolve, sep } from 'node:path';
import { fileURLToPath } from 'node:url';

const repositoryRoot = resolve(dirname(fileURLToPath(import.meta.url)), '..');
const distDirectory = join(repositoryRoot, 'dist');
const nestedPath = '/deep/nested/app/';
const mimeTypes = {
  '.css': 'text/css',
  '.html': 'text/html',
  '.ico': 'image/x-icon',
  '.js': 'text/javascript',
  '.json': 'application/json',
  '.png': 'image/png',
  '.svg': 'image/svg+xml',
};

const server = createServer(async (request, response) => {
  try {
    const requestUrl = new URL(request.url ?? '/', 'http://localhost');

    if (requestUrl.pathname === '/toolbox.catalog.json') {
      response.setHeader('content-type', 'application/json');
      response.end(
        JSON.stringify({
          schemaVersion: 1,
          id: 'nested-smoke-test',
          name: 'Nested smoke test',
          home: './',
          theme: {
            mode: 'system',
            brand: 'Nested smoke test',
          },
          apps: [
            {
              manifest: `${nestedPath}toolbox-app.json`,
              enabled: true,
            },
          ],
        })
      );
      return;
    }

    if (!requestUrl.pathname.startsWith(nestedPath)) {
      response.writeHead(404).end();
      return;
    }

    const requestedPath = decodeURIComponent(
      requestUrl.pathname.slice(nestedPath.length)
    );
    const filePath = resolve(
      distDirectory,
      requestedPath === '' ? 'index.html' : requestedPath
    );

    if (
      filePath !== distDirectory &&
      !filePath.startsWith(`${distDirectory}${sep}`)
    ) {
      response.writeHead(403).end();
      return;
    }

    if (!(await stat(filePath)).isFile()) {
      response.writeHead(404).end();
      return;
    }

    response.setHeader(
      'content-type',
      mimeTypes[extname(filePath)] ?? 'application/octet-stream'
    );
    response.end(await readFile(filePath));
  } catch {
    response.writeHead(404).end();
  }
});

await new Promise((resolveListening) => {
  server.listen(0, '127.0.0.1', resolveListening);
});

try {
  const address = server.address();
  if (!address || typeof address === 'string') {
    throw new Error('Static smoke server did not expose a TCP port.');
  }

  const appUrl = `http://127.0.0.1:${address.port}${nestedPath}`;
  const standaloneHtml = await fetchText(appUrl);
  const toolboxHtml = await fetchText(
    `${appUrl}?toolbox=${encodeURIComponent('/toolbox.catalog.json')}`
  );

  if (toolboxHtml !== standaloneHtml) {
    throw new Error('Toolbox mode did not serve the same static app artifact.');
  }

  const assetReferences = Array.from(
    standaloneHtml.matchAll(/(?:href|src)="([^"]+)"/g),
    (match) => match[1]
  ).filter(
    (reference) =>
      !reference.startsWith('#') &&
      !reference.startsWith('data:') &&
      !reference.startsWith('http:') &&
      !reference.startsWith('https:')
  );

  for (const reference of assetReferences) {
    const resolved = new URL(reference, appUrl);
    if (!resolved.pathname.startsWith(nestedPath)) {
      throw new Error(
        `Built asset escaped the nested app path: ${reference} -> ${resolved.pathname}`
      );
    }
    await fetchOk(resolved);
  }

  const manifestUrl = new URL('toolbox-app.json', appUrl);
  const manifest = JSON.parse(await fetchText(manifestUrl));
  await fetchOk(new URL(manifest.entry, appUrl));
  await fetchOk(new URL(manifest.icon, manifestUrl));
  await fetchOk(new URL('vendor/saxon/SaxonJS2.js', appUrl));
  await fetchOk(`http://127.0.0.1:${address.port}/toolbox.catalog.json`);

  console.log(
    `Static smoke test passed at ${nestedPath} in standalone and toolbox modes.`
  );
} finally {
  await new Promise((resolveClosed, reject) => {
    server.close((error) => (error ? reject(error) : resolveClosed()));
  });
}

async function fetchOk(url) {
  const response = await fetch(url);
  if (!response.ok) {
    throw new Error(
      `Expected ${url} to be available, received HTTP ${response.status}.`
    );
  }
  return response;
}

async function fetchText(url) {
  return (await fetchOk(url)).text();
}