import { watch } from 'fs';

const SRC_DIR = 'src';

async function spawnServer() {
  return Bun.spawn(['bun', 'run', 'src/index.tsx'], {
    stdio: ['inherit', 'inherit', 'inherit'],
  });
}

async function restart(current: ReturnType<typeof Bun.spawn>) {
  current.kill();
  await current.exited;
  return spawnServer();
}

let server = await spawnServer();

// Debounce rapid file-save bursts (e.g. formatter touching many files at once)
let debounce: ReturnType<typeof setTimeout> | null = null;
watch(SRC_DIR, { recursive: true }, (_, filename) => {
  if (filename?.endsWith('.css')) return; // CSS is handled by build-css.ts --watch
  if (debounce) clearTimeout(debounce);
  debounce = setTimeout(async () => {
    console.clear();
    console.log(`[dev] ${filename} changed — restarting…`);
    server = await restart(server);
  }, 50);
});

const css = Bun.spawn(['bun', 'scripts/build-css.ts', '--watch'], {
  stdio: ['inherit', 'inherit', 'inherit'],
});

process.on('SIGINT', async () => {
  server.kill();
  css.kill();
  await Promise.all([server.exited, css.exited]);
  process.exit(0);
});

await Promise.all([server.exited, css.exited]);