/**
 * AD/LDAP routes module.
 */
const express = require('express');
const { authMiddleware, adminMiddleware } = require('../middleware/auth');
const { auditLog } = require('../auditLog');
const { isLDAPConfigured } = require('../ldapSync');
const { browseOUTree, createADUser, checkADUserExists, deleteADUser } = require('../ldapOperations');
const { searchADGroups, addUserToGroups, browseADGroups } = require('../ldapOperations');
const { validate, createADUserSchema, deleteADUserSchema } = require('../middleware/validation');

const router = express.Router();

// LDAP Status Endpoint (public)
router.get('/status', (req, res) => {
  res.json({ configured: isLDAPConfigured() });
});

// All other AD routes require auth
router.use(authMiddleware);

// Browse OU tree
router.get('/ou-tree', (req, res) => {
  const { base } = req.query;
  browseOUTree(base || undefined).then(ous => {
    res.json(ous);
  }).catch(err => {
    console.error('[ERROR] GET /ad/ou-tree -', err.message);
    res.status(500).json({ error: 'Interner Serverfehler.' });
  });
});

// Search AD groups (all security groups)
router.get('/groups', (req, res) => {
  const { q } = req.query;
  if (!q || q.trim().length < 2) {
    return res.json([]);
  }
  searchADGroups(q.trim()).then(groups => {
    res.json(groups);
  }).catch(err => {
    console.error('[ERROR] GET /ad/groups -', err.message);
    res.status(500).json({ error: 'Interner Serverfehler.' });
  });
});

// Browse all AD groups (for tree display)
router.get('/groups-tree', (req, res) => {
  browseADGroups().then(groups => {
    res.json(groups);
  }).catch(err => {
    console.error('[ERROR] GET /ad/groups-tree -', err.message);
    res.status(500).json({ error: 'Interner Serverfehler.' });
  });
});

// Get AD create config
router.get('/create-config', (req, res) => {
  res.json({
    configured: isLDAPConfigured(),
    createOU: process.env.LDAP_CREATE_OU || '',
    upnSuffix: process.env.LDAP_UPN_SUFFIX || process.env.LDAP_BIND_USER?.split('@')[1] || '',
  });
});

// Create AD user (admin only)
router.post('/create-user', adminMiddleware, validate(createADUserSchema), async (req, res) => {
  const { ou, vorname, nachname, email, username, password, department, telefon, titel, displayName, physicalDeliveryOfficeName, company, description, wWWHomePage, streetAddress, postOfficeBox, l, st, postalCode, c, groups } = req.validatedBody;

  try {
    let sAMAccountName = username;
    if (vorname && nachname) {
      sAMAccountName = nachname.replace(/ä/g, 'ae').replace(/ö/g, 'oe').replace(/ü/g, 'ue')
        .replace(/Ä/g, 'Ae').replace(/Ö/g, 'Oe').replace(/Ü/g, 'Ue').replace(/ß/g, 'ss')
        + vorname.charAt(0).replace(/ä/g, 'ae').replace(/ö/g, 'oe').replace(/ü/g, 'ue')
          .replace(/Ä/g, 'Ae').replace(/Ö/g, 'Oe').replace(/Ü/g, 'Ue').replace(/ß/g, 'ss');
      sAMAccountName = sAMAccountName.replace(/[^a-zA-Z0-9]/g, '').substring(0, 20);
    }

    const existing = await checkADUserExists(username, sAMAccountName);
    if (existing) {
      return res.status(409).json({ error: 'Benutzername "' + username + '" existiert bereits im Active Directory.', dn: existing.distinguishedName });
    }

    const result = await createADUser({ ou, vorname, nachname, email, username, password, department, telefon, titel, displayName, physicalDeliveryOfficeName, company, description, wWWHomePage, streetAddress, postOfficeBox, l, st, postalCode, c });
    if (result.warning && result.dn) {
      auditLog(req.user?.id, 'ad.create-user', 'ad_user', null, `AD user created with warning: ${username} - ${result.warning}`);
    } else {
      auditLog(req.user?.id, 'ad.create-user', 'ad_user', null, `Created AD user: ${username}`);
    }

    // Add user to groups if specified
    let groupResults = [];
    if (groups && Array.isArray(groups) && groups.length > 0 && result.dn) {
      try {
        groupResults = await addUserToGroups(result.dn, groups);
        const addedCount = groupResults.filter(r => r.status === 'added').length;
        auditLog(req.user?.id, 'ad.create-user', 'ad_user', null, `Added ${username} to ${addedCount} group(s)`);
      } catch (groupErr) {
        console.error('[WARN] Gruppenzuweisung fehlgeschlagen:', groupErr.message);
        groupResults = groups.map(dn => ({ dn, status: 'error', error: groupErr.message }));
      }
    }

    res.status(201).json({ ...result, groupResults });
  } catch (err) {
    auditLog(req.user?.id, 'ad.create-user-failed', 'ad_user', null, `Failed to create AD user: ${username} - ${err.message}`);
    res.status(500).json({ error: 'Interner Serverfehler.' });
  }
});

// Delete AD user (admin only)
router.delete('/delete-user', adminMiddleware, validate(deleteADUserSchema), async (req, res) => {
  const { dn } = req.validatedBody;
  try {
    await deleteADUser(dn);
    auditLog(req.user?.id, 'ad.delete-user', 'ad_user', null, `Deleted AD user: ${dn}`);
    res.json({ success: true, message: 'Benutzer erfolgreich gelöscht.' });
  } catch (err) {
    res.status(500).json({ error: 'Fehler beim Löschen des AD-Benutzers: ' + err.message });
  }
});

module.exports = router;