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

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

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

      // Validate request body
      const { subject, start, end, body, location, attendees, isOnlineMeeting } = req.body;

      if (!subject || !start || !end) {
        return res.status(400).json({
          error: 'Missing required fields',
          required: ['subject', 'start', 'end'],
          hint: 'start and end must have dateTime and timeZone properties',
        });
      }

      // Validate start and end format
      if (!start.dateTime || !start.timeZone) {
        return res.status(400).json({
          error: 'Invalid start format',
          hint: 'start must have dateTime and timeZone properties',
        });
      }

      if (!end.dateTime || !end.timeZone) {
        return res.status(400).json({
          error: 'Invalid end format',
          hint: 'end must have dateTime and timeZone properties',
        });
      }

      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) });
      }

      // Build event object
      const event: any = {
        subject,
        start,
        end,
      };

      // Add optional fields if provided
      if (body) {
        event.body = {
          contentType: body.contentType || 'HTML',
          content: body.content || body,
        };
      }

      if (location) {
        event.location = typeof location === 'string' ? { displayName: location } : location;
      }

      if (attendees && Array.isArray(attendees)) {
        event.attendees = attendees.map((attendee) => ({
          emailAddress: typeof attendee === 'string' ? { address: attendee } : attendee.emailAddress,
          type: attendee.type || 'required',
        }));
      }

      if (isOnlineMeeting !== undefined) {
        event.isOnlineMeeting = isOnlineMeeting;
      }

      console.log('📅 Creating event:', event.subject);

      // Create event via Graph API
      const data = await postGraph('/me/events', token, event);

      res.status(201).json(data);
    } catch (err: any) {
      console.error('Create event error:', err.message);
      res.status(500).json({ error: err.message });
    }
  });

  return router;
};