import { readFile } from 'node:fs/promises';
import type { NextApiRequest, NextApiResponse } from 'next';

export default async function handler(req: NextApiRequest, res: NextApiResponse) {
  if (process.env.PREVIEW_MODE !== 'true') return res.status(404).end();
  if (req.method !== 'GET' && req.method !== 'HEAD') return res.status(405).end();
  res.setHeader('Cache-Control', 'no-store');
  try {
    const status = JSON.parse(await readFile('/preview-status/status.json', 'utf8'));
    return req.method === 'HEAD' ? res.status(200).end() : res.status(200).json({ ...status, mode: 'development' });
  } catch {
    return res.status(503).json({ error: 'Preview source has not synchronized yet' });
  }
}