import { spawn } from 'node:child_process';
import fs from 'node:fs';
import http from 'node:http';
import path from 'node:path';

const vendorDir = path.resolve('vendor/funclip');
const entryFile = path.join(vendorDir, 'funclip', 'launch.py');
const projectVenvPython = path.resolve('.venv-funclip/bin/python');
const pythonCommand =
  process.env.TRUEGROWTH_FUNCLIP_PYTHON ||
  (fs.existsSync(projectVenvPython) ? projectVenvPython : 'python3');
const port = process.env.TRUEGROWTH_FUNCLIP_PORT || '7860';
const lang = process.env.TRUEGROWTH_FUNCLIP_LANG || 'zh';
const serviceUrl = `http://127.0.0.1:${port}`;

function probeFunClip() {
  return new Promise((resolve) => {
    const request = http.get(serviceUrl, (response) => {
      response.resume();
      resolve(response.statusCode ? response.statusCode < 500 : true);
    });
    request.setTimeout(1600, () => {
      request.destroy();
      resolve(false);
    });
    request.on('error', () => resolve(false));
  });
}

function waitUntilStopped() {
  return new Promise((resolve) => {
    const timer = setInterval(() => undefined, 60_000);
    const stop = () => {
      clearInterval(timer);
      resolve();
    };
    process.once('SIGINT', stop);
    process.once('SIGTERM', stop);
  });
}

if (!fs.existsSync(entryFile)) {
  console.error(`FunClip launch.py not found: ${entryFile}`);
  process.exit(1);
}

if (await probeFunClip()) {
  console.log(
    `FunClip already running at ${serviceUrl}; reusing existing service.`
  );
  await waitUntilStopped();
}

const child = spawn(
  pythonCommand,
  ['funclip/launch.py', '--port', port, '--lang', lang],
  {
    cwd: vendorDir,
    stdio: 'inherit',
  }
);

const shutdown = () => {
  if (!child.killed) {
    child.kill('SIGTERM');
  }
};

process.on('SIGINT', shutdown);
process.on('SIGTERM', shutdown);
child.on('exit', (code) => process.exit(code ?? 0));