import {
  AngularNodeAppEngine,
  createNodeRequestHandler,
  isMainModule,
  writeResponseToNodeResponse,
} from '@angular/ssr/node';
import * as http from 'node:http';

/**
 * Manually import and register the Angular app engine manifest.
 * The Angular 21 builder generates angular-app-engine-manifest.mjs at build time
 * but does NOT automatically inject the import into server.mjs.
 * Without this, AngularNodeAppEngine fails with "Angular app engine manifest is not set"
 * and every SSR request returns 404.
 */
// @ts-ignore — generated at build time by @angular/build
import engineManifest from './angular-app-engine-manifest.mjs';
import { ɵsetAngularAppEngineManifest } from '@angular/ssr';
ɵsetAngularAppEngineManifest(engineManifest);

const appEngine = new AngularNodeAppEngine();

const requestHandler = createNodeRequestHandler(async (req, res, next) => {
  try {
    const response = await appEngine.handle(req);

    if (response) {
      await writeResponseToNodeResponse(response, res);
    } else {
      next();
    }
  } catch (error) {
    next(error);
  }
});

if (isMainModule(import.meta.url)) {
  console.log('Node.js SSR server ready');
  const server = http.createServer();
  server.on('request', async (req, res) => {
    try {
      await requestHandler(req, res, () => {
        res.statusCode = 404;
        res.end('Not Found');
      });
    } catch (error) {
      console.error('SSR error:', error);
      res.statusCode = 500;
      res.end('Internal server error');
    }
  });
  server.listen(4200, () => {
    console.log('SSR server listening on http://localhost:4200');
  });
}

export { requestHandler };