import * as esbuild from 'esbuild';

// Shim unused Node.js built-ins that get pulled in by dependencies.
const nodeShimPlugin: esbuild.Plugin = {
  name: 'node-builtins-shim',
  setup(build) {
    // Mark node built-ins as empty modules — they are imported but not actually used at runtime.
    const builtins = ['path', 'fs', 'os', 'crypto', 'stream', 'util', 'events', 'http', 'https', 'net', 'tls', 'child_process', 'url', 'assert', 'buffer', 'tty', 'readline'];
    const filter = new RegExp(`^(${builtins.join('|')})$`);
    build.onResolve({ filter }, (args) => ({
      path: args.path,
      namespace: 'node-shim',
    }));
    build.onLoad({ filter: /.*/, namespace: 'node-shim' }, () => ({
      contents: 'export default {};',
      loader: 'js',
    }));
  },
};

const buildOptions: esbuild.BuildOptions = {
  entryPoints: ['demo/demo.web.ts'],
  bundle: true,
  format: 'esm',
  platform: 'browser',
  outdir: 'demo',
  sourcemap: true,
  target: 'es2022',
  logLevel: 'info',
  plugins: [nodeShimPlugin],
};

const serve = process.argv.includes('--serve');

if (serve) {
  const ctx = await esbuild.context(buildOptions);
  const { host, port } = await ctx.serve({ servedir: 'demo' });
  console.log(`\n  🌐 Web demo running at http://localhost:${port}/demo.web.html\n`);
} else {
  await esbuild.build(buildOptions);
}