import { Router } from 'express';
import { patchGraph } from '../utils/index.ts';
import { acquireAppToken } from '../helper/msal.ts';

import { AuthManager } from '../auth/index.ts';

export default (auth?: AuthManager) => {
  const router = Router();

  router.patch('/:id', async (req, res) => {
    try {
      // Authentication handled via client credentials (resolveCredential + createMsalClient)

      let token: string;
      try {
        token = await acquireAppToken(req, auth);
      } catch (err: any) {
        return res.status(401).json({ error: 'Failed to acquire access token', message: err?.message ?? String(err) });
      }

      const eventId = req.params.id;
      const { subject, start, end, body, location } = req.body;

      const eventPayload: any = {};
      if (subject) eventPayload.subject = subject;
      if (start) eventPayload.start = { dateTime: start, timeZone: 'UTC' };
      if (end) eventPayload.end = { dateTime: end, timeZone: 'UTC' };
      if (body) eventPayload.body = { contentType: 'HTML', content: body };
      if (location) eventPayload.location = { displayName: location };

      const data = await patchGraph(`/me/events/${eventId}`, token, eventPayload);
      res.json(data);
    } catch (err: any) {
      res.status(500).json({ error: err.message });
    }
  });

  return router;
};