update

2026-03-16 15:01:09 +01:00
parent 3c72fe627f
commit f3ad989a9e
28 changed files with 794 additions and 52 deletions
--- a/backend/src/controllers/atemschutz.controller.ts
+++ b/backend/src/controllers/atemschutz.controller.ts
@@ -1,5 +1,6 @@
 import { Request, Response } from 'express';
 import atemschutzService from '../services/atemschutz.service';
+import notificationService from '../services/notification.service';
 import { CreateAtemschutzSchema, UpdateAtemschutzSchema } from '../models/atemschutz.model';
 import logger from '../utils/logger';

@@ -159,6 +160,49 @@ class AtemschutzController {
    }
  }

+  async getExpiring(req: Request, res: Response): Promise<void> {
+    try {
+      const expiring = await atemschutzService.getExpiringCertifications(30);
+
+      // Side-effect: create notifications for expiring certifications (dedup via DB constraint)
+      for (const item of expiring) {
+        if (item.untersuchung_status !== 'ok') {
+          await notificationService.createNotification({
+            user_id: item.user_id,
+            typ: 'atemschutz_expiry',
+            titel: item.untersuchung_status === 'abgelaufen'
+              ? 'G26 Untersuchung abgelaufen'
+              : 'G26 Untersuchung läuft bald ab',
+            nachricht: `Ihre G26 Untersuchung ${item.untersuchung_status === 'abgelaufen' ? 'ist abgelaufen' : 'läuft bald ab'}.`,
+            schwere: item.untersuchung_status === 'abgelaufen' ? 'fehler' : 'warnung',
+            quell_typ: 'atemschutz_untersuchung',
+            quell_id: item.id,
+            link: '/atemschutz',
+          });
+        }
+        if (item.leistungstest_status !== 'ok') {
+          await notificationService.createNotification({
+            user_id: item.user_id,
+            typ: 'atemschutz_expiry',
+            titel: item.leistungstest_status === 'abgelaufen'
+              ? 'Leistungstest abgelaufen'
+              : 'Leistungstest läuft bald ab',
+            nachricht: `Ihr Leistungstest ${item.leistungstest_status === 'abgelaufen' ? 'ist abgelaufen' : 'läuft bald ab'}.`,
+            schwere: item.leistungstest_status === 'abgelaufen' ? 'fehler' : 'warnung',
+            quell_typ: 'atemschutz_leistungstest',
+            quell_id: item.id,
+            link: '/atemschutz',
+          });
+        }
+      }
+
+      res.status(200).json({ success: true, data: expiring });
+    } catch (error) {
+      logger.error('Atemschutz getExpiring error', { error });
+      res.status(500).json({ success: false, message: 'Ablaufende Zertifizierungen konnten nicht geladen werden' });
+    }
+  }
+
  async delete(req: Request, res: Response): Promise<void> {
    try {
      const { id } = req.params as Record<string, string>;
--- a/backend/src/controllers/booking.controller.ts
+++ b/backend/src/controllers/booking.controller.ts
@@ -1,6 +1,7 @@
 import { Request, Response } from 'express';
 import { ZodError } from 'zod';
 import bookingService from '../services/booking.service';
+import vehicleService from '../services/vehicle.service';
 import {
  CreateBuchungSchema,
  UpdateBuchungSchema,
@@ -52,12 +53,13 @@ class BookingController {
        res.status(400).json({ success: false, message: 'from und to sind erforderlich' });
        return;
      }
-      const bookings = await bookingService.getBookingsByRange(
-        new Date(from as string),
-        new Date(to as string),
-        fahrzeugId as string | undefined
-      );
-      res.json({ success: true, data: bookings });
+      const fromDate = new Date(from as string);
+      const toDate = new Date(to as string);
+      const [bookings, maintenanceWindows] = await Promise.all([
+        bookingService.getBookingsByRange(fromDate, toDate, fahrzeugId as string | undefined),
+        vehicleService.getMaintenanceWindows(fromDate, toDate),
+      ]);
+      res.json({ success: true, data: { bookings, maintenanceWindows } });
    } catch (error) {
      logger.error('Booking getCalendarRange error', { error });
      res.status(500).json({ success: false, message: 'Buchungen konnten nicht geladen werden' });
--- a/backend/src/controllers/events.controller.ts
+++ b/backend/src/controllers/events.controller.ts
@@ -118,6 +118,39 @@ class EventsController {
    }
  };

+  // -------------------------------------------------------------------------
+  // GET /api/events/conflicts?from=<ISO>&to=<ISO>&excludeId=<uuid>
+  // -------------------------------------------------------------------------
+  checkConflicts = async (req: Request, res: Response): Promise<void> => {
+    try {
+      const fromStr = req.query.from as string | undefined;
+      const toStr = req.query.to as string | undefined;
+      const excludeId = req.query.excludeId as string | undefined;
+
+      if (!fromStr || !toStr) {
+        res.status(400).json({
+          success: false,
+          message: 'Query-Parameter "from" und "to" sind erforderlich (ISO-8601)',
+        });
+        return;
+      }
+
+      const from = new Date(fromStr);
+      const to = new Date(toStr);
+
+      if (isNaN(from.getTime()) || isNaN(to.getTime())) {
+        res.status(400).json({ success: false, message: 'Ungültiges Datumsformat' });
+        return;
+      }
+
+      const data = await eventsService.checkConflicts(from, to, excludeId);
+      res.json({ success: true, data });
+    } catch (error) {
+      logger.error('checkConflicts error', { error });
+      res.status(500).json({ success: false, message: 'Fehler bei der Konfliktprüfung' });
+    }
+  };
+
  // -------------------------------------------------------------------------
  // GET /api/events/calendar?from=<ISO>&to=<ISO>
  // -------------------------------------------------------------------------
--- a/backend/src/controllers/serviceMonitor.controller.ts
+++ b/backend/src/controllers/serviceMonitor.controller.ts
@@ -21,8 +21,37 @@ const broadcastSchema = z.object({
  nachricht: z.string().min(1).max(2000),
  schwere: z.enum(['info', 'warnung', 'fehler']).default('info'),
  targetGroup: z.string().optional(),
+  targetDienstgrad: z.array(z.string()).optional(),
 });

+const broadcastFilterSchema = z.object({
+  targetGroup: z.string().optional(),
+  targetDienstgrad: z.array(z.string()).optional(),
+});
+
+function buildFilteredUserQuery(filters: { targetGroup?: string; targetDienstgrad?: string[] }): { text: string; values: unknown[] } {
+  const conditions: string[] = ['u.is_active = TRUE'];
+  const values: unknown[] = [];
+  let paramIndex = 1;
+
+  if (filters.targetGroup) {
+    conditions.push(`$${paramIndex} = ANY(u.authentik_groups)`);
+    values.push(filters.targetGroup);
+    paramIndex++;
+  }
+
+  if (filters.targetDienstgrad && filters.targetDienstgrad.length > 0) {
+    conditions.push(`mp.dienstgrad = ANY($${paramIndex})`);
+    values.push(filters.targetDienstgrad);
+    paramIndex++;
+  }
+
+  const needsJoin = filters.targetDienstgrad && filters.targetDienstgrad.length > 0;
+  const text = `SELECT DISTINCT u.id FROM users u${needsJoin ? ' LEFT JOIN member_profiles mp ON mp.user_id = u.id' : ''} WHERE ${conditions.join(' AND ')}`;
+
+  return { text, values };
+}
+
 class ServiceMonitorController {
  async getAll(_req: Request, res: Response): Promise<void> {
    try {
@@ -160,21 +189,11 @@ class ServiceMonitorController {

  async broadcastNotification(req: Request, res: Response): Promise<void> {
    try {
-      const { titel, nachricht, schwere, targetGroup } = broadcastSchema.parse(req.body);
+      const { titel, nachricht, schwere, targetGroup, targetDienstgrad } = broadcastSchema.parse(req.body);

-      let users;
-      if (targetGroup) {
-        const result = await pool.query(
-          `SELECT id FROM users WHERE is_active = TRUE AND $1 = ANY(authentik_groups)`,
-          [targetGroup]
-        );
-        users = result.rows;
-      } else {
-        const result = await pool.query(
-          `SELECT id FROM users WHERE is_active = TRUE`
-        );
-        users = result.rows;
-      }
+      const query = buildFilteredUserQuery({ targetGroup, targetDienstgrad });
+      const result = await pool.query(query.text, query.values);
+      const users = result.rows;

      let sent = 0;
      for (const user of users) {
@@ -198,6 +217,24 @@ class ServiceMonitorController {
      res.status(500).json({ success: false, message: 'Failed to broadcast notification' });
    }
  }
+
+  async broadcastPreview(req: Request, res: Response): Promise<void> {
+    try {
+      const { targetGroup, targetDienstgrad } = broadcastFilterSchema.parse(req.body);
+
+      const query = buildFilteredUserQuery({ targetGroup, targetDienstgrad });
+      const result = await pool.query(query.text, query.values);
+
+      res.json({ success: true, data: { count: result.rows.length } });
+    } catch (error) {
+      if (error instanceof z.ZodError) {
+        res.status(400).json({ success: false, message: 'Invalid input', errors: error.issues });
+        return;
+      }
+      logger.error('Failed to preview broadcast', { error });
+      res.status(500).json({ success: false, message: 'Failed to preview broadcast' });
+    }
+  }
 }

 export default new ServiceMonitorController();
--- a/backend/src/controllers/vehicle.controller.ts
+++ b/backend/src/controllers/vehicle.controller.ts
@@ -1,6 +1,7 @@
 import { Request, Response } from 'express';
 import { z } from 'zod';
 import vehicleService from '../services/vehicle.service';
+import equipmentService from '../services/equipment.service';
 import { FahrzeugStatus } from '../models/vehicle.model';
 import logger from '../utils/logger';

@@ -140,6 +141,69 @@ class VehicleController {
    }
  }

+  async exportAlerts(_req: Request, res: Response): Promise<void> {
+    try {
+      const escape = (v: unknown): string => {
+        if (v === null || v === undefined) return '';
+        const str = String(v);
+        let safe = str.replace(/"/g, '""');
+        if (/^[=+@\-]/.test(safe)) safe = "'" + safe;
+        return `"${safe}"`;
+      };
+
+      const formatDate = (d: Date | string | null): string => {
+        if (!d) return '';
+        const date = typeof d === 'string' ? new Date(d) : d;
+        const day = String(date.getDate()).padStart(2, '0');
+        const month = String(date.getMonth() + 1).padStart(2, '0');
+        const year = date.getFullYear();
+        return `${day}.${month}.${year}`;
+      };
+
+      const [vehicleAlerts, equipmentAlerts] = await Promise.all([
+        vehicleService.getUpcomingInspections(365),
+        equipmentService.getUpcomingInspections(365),
+      ]);
+
+      const header = 'Typ,Bezeichnung,Kurzname,Prüfungsart,Fällig am,Tage verbleibend';
+      const rows: string[] = [];
+
+      for (const a of vehicleAlerts) {
+        const pruefungsart = a.type === '57a' ? '§57a Überprüfung' : 'Nächste Wartung';
+        rows.push([
+          escape('Fahrzeug'),
+          escape(a.bezeichnung),
+          escape(a.kurzname),
+          escape(pruefungsart),
+          escape(formatDate(a.faelligAm)),
+          escape(a.tage),
+        ].join(','));
+      }
+
+      for (const e of equipmentAlerts) {
+        rows.push([
+          escape('Ausrüstung'),
+          escape(e.bezeichnung),
+          escape(''),
+          escape('Prüfung'),
+          escape(formatDate(e.naechste_pruefung_am)),
+          escape(e.pruefung_tage_bis_faelligkeit),
+        ].join(','));
+      }
+
+      const today = new Date();
+      const dateStr = `${today.getFullYear()}-${String(today.getMonth() + 1).padStart(2, '0')}-${String(today.getDate()).padStart(2, '0')}`;
+      const csv = '\uFEFF' + header + '\n' + rows.join('\n');
+
+      res.setHeader('Content-Type', 'text/csv; charset=utf-8');
+      res.setHeader('Content-Disposition', `attachment; filename="pruefungen_${dateStr}.csv"`);
+      res.status(200).send(csv);
+    } catch (error) {
+      logger.error('exportAlerts error', { error });
+      res.status(500).json({ success: false, message: 'Prüfungsexport konnte nicht erstellt werden' });
+    }
+  }
+
  async getVehicle(req: Request, res: Response): Promise<void> {
    try {
      const { id } = req.params as Record<string, string>;
--- a/backend/src/routes/atemschutz.routes.ts
+++ b/backend/src/routes/atemschutz.routes.ts
@@ -9,6 +9,7 @@ const router = Router();

 router.get('/',           authenticate, atemschutzController.list.bind(atemschutzController));
 router.get('/stats',      authenticate, atemschutzController.getStats.bind(atemschutzController));
+router.get('/expiring',   authenticate, atemschutzController.getExpiring.bind(atemschutzController));
 router.get('/my-status',     authenticate, atemschutzController.getMyStatus.bind(atemschutzController));
 router.get('/user/:userId',  authenticate, atemschutzController.getByUserId.bind(atemschutzController));
 router.get('/:id',           authenticate, atemschutzController.getOne.bind(atemschutzController));
--- a/backend/src/routes/events.routes.ts
+++ b/backend/src/routes/events.routes.ts
@@ -58,6 +58,16 @@ router.delete(
 */
 router.get('/groups', authenticate, eventsController.getAvailableGroups.bind(eventsController));

+// ---------------------------------------------------------------------------
+// Conflict check — must come before /:id
+// ---------------------------------------------------------------------------
+
+/**
+ * GET /api/events/conflicts?from=<ISO>&to=<ISO>&excludeId=<uuid>
+ * Check for overlapping events in the given time range.
+ */
+router.get('/conflicts', authenticate, eventsController.checkConflicts.bind(eventsController));
+
 // ---------------------------------------------------------------------------
 // Calendar & upcoming — specific routes must come before /:id
 // ---------------------------------------------------------------------------
--- a/backend/src/routes/serviceMonitor.routes.ts
+++ b/backend/src/routes/serviceMonitor.routes.ts
@@ -17,5 +17,6 @@ router.delete('/services/:id', ...auth, serviceMonitorController.delete.bind(ser
 router.get('/system/health', ...auth, serviceMonitorController.getSystemHealth.bind(serviceMonitorController));
 router.get('/users', ...auth, serviceMonitorController.getUsers.bind(serviceMonitorController));
 router.post('/notifications/broadcast', ...auth, serviceMonitorController.broadcastNotification.bind(serviceMonitorController));
+router.post('/notifications/broadcast/preview', ...auth, serviceMonitorController.broadcastPreview.bind(serviceMonitorController));

 export default router;
--- a/backend/src/routes/vehicle.routes.ts
+++ b/backend/src/routes/vehicle.routes.ts
@@ -10,6 +10,7 @@ const router = Router();
 router.get('/',       authenticate, vehicleController.listVehicles.bind(vehicleController));
 router.get('/stats',  authenticate, vehicleController.getStats.bind(vehicleController));
 router.get('/alerts', authenticate, vehicleController.getAlerts.bind(vehicleController));
+router.get('/alerts/export', authenticate, requirePermission('vehicles:read'), vehicleController.exportAlerts.bind(vehicleController));
 router.get('/:id',    authenticate, vehicleController.getVehicle.bind(vehicleController));
 router.get('/:id/wartung', authenticate, vehicleController.getWartung.bind(vehicleController));

--- a/backend/src/services/atemschutz.service.ts
+++ b/backend/src/services/atemschutz.service.ts
@@ -216,6 +216,45 @@ class AtemschutzService {
    }
  }

+  // =========================================================================
+  // EXPIRING CERTIFICATIONS
+  // =========================================================================
+
+  async getExpiringCertifications(daysAhead = 30): Promise<any[]> {
+    try {
+      const result = await pool.query(`
+        SELECT
+          at.id, at.user_id, u.email,
+          COALESCE(u.name, u.email) as user_name,
+          at.untersuchung_gueltig_bis,
+          at.leistungstest_gueltig_bis,
+          CASE
+            WHEN at.untersuchung_gueltig_bis < CURRENT_DATE THEN 'abgelaufen'
+            WHEN at.untersuchung_gueltig_bis <= CURRENT_DATE + $1 THEN 'bald_faellig'
+            ELSE 'ok'
+          END as untersuchung_status,
+          CASE
+            WHEN at.leistungstest_gueltig_bis < CURRENT_DATE THEN 'abgelaufen'
+            WHEN at.leistungstest_gueltig_bis <= CURRENT_DATE + $1 THEN 'bald_faellig'
+            ELSE 'ok'
+          END as leistungstest_status
+        FROM atemschutz_traeger at
+        JOIN users u ON u.id = at.user_id
+        WHERE at.einsatzbereit = TRUE
+          AND (
+            at.untersuchung_gueltig_bis <= CURRENT_DATE + $1
+            OR at.leistungstest_gueltig_bis <= CURRENT_DATE + $1
+          )
+        ORDER BY LEAST(at.untersuchung_gueltig_bis, at.leistungstest_gueltig_bis) ASC
+      `, [`${daysAhead} days`]);
+
+      return result.rows;
+    } catch (error) {
+      logger.error('AtemschutzService.getExpiringCertifications fehlgeschlagen', { error });
+      throw new Error('Ablaufende Atemschutz-Zertifizierungen konnten nicht geladen werden');
+    }
+  }
+
  // =========================================================================
  // DASHBOARD KPI / STATISTIKEN
  // =========================================================================
--- a/backend/src/services/audit.service.ts
+++ b/backend/src/services/audit.service.ts
@@ -14,6 +14,7 @@

 import pool from '../config/database';
 import logger from '../utils/logger';
+import notificationService from './notification.service';

 // ---------------------------------------------------------------------------
 // Enums — kept as const objects rather than TypeScript enums so that the
@@ -188,6 +189,9 @@ class AuditService {
        resource_id:   entry.resource_id,
        user_id:       entry.user_id,
      });
+
+      // Fire-and-forget — never block the audit log write
+      this.alertAdminsIfSensitive(entry).catch(() => {});
    } catch (error) {
      // GDPR obligation: log the failure so it can be investigated, but
      // NEVER propagate — the main request must complete successfully.
@@ -203,6 +207,64 @@ class AuditService {
    }
  }

+  // -------------------------------------------------------------------------
+  // Audit alert notifications for admins
+  // -------------------------------------------------------------------------
+
+  /**
+   * alertAdminsIfSensitive — checks whether an audit entry represents a
+   * sensitive action and, if so, creates a notification for every active
+   * admin user (except the actor themselves).
+   *
+   * This method MUST NEVER throw.  All errors are caught and logged.
+   */
+  async alertAdminsIfSensitive(entry: AuditLogInput): Promise<void> {
+    try {
+      const sensitiveActions: Record<string, string> = {
+        'PERMISSION_DENIED': 'Zugriff verweigert',
+        'DELETE':            'Datensatz gelöscht',
+        'ROLE_CHANGE':       'Rolle geändert',
+      };
+
+      const isUserUpdate =
+        entry.resource_type === AuditResourceType.USER &&
+        entry.action === AuditAction.UPDATE;
+      const isSensitive = sensitiveActions[entry.action] || isUserUpdate;
+
+      if (!isSensitive) return;
+
+      // Get all active admin users
+      const { rows: admins } = await pool.query(
+        "SELECT id FROM users WHERE is_active = TRUE AND 'dashboard_admin' = ANY(authentik_groups)"
+      );
+
+      if (admins.length === 0) return;
+
+      const titel = sensitiveActions[entry.action] || 'Benutzer-Änderung';
+      const nachricht = `${entry.action} auf ${entry.resource_type}${entry.resource_id ? ' ' + entry.resource_id : ''} durch ${entry.user_email ?? 'System'}`;
+
+      for (const admin of admins) {
+        // Don't notify the admin about their own actions
+        if (admin.id === entry.user_id) continue;
+
+        await notificationService.createNotification({
+          user_id:   admin.id,
+          typ:       'audit_alert',
+          titel,
+          nachricht,
+          schwere:   entry.action === 'PERMISSION_DENIED' ? 'warnung' : 'info',
+          quell_typ: 'audit_alert',
+          quell_id:  `${entry.action}_${entry.resource_type}_${entry.resource_id ?? Date.now()}`,
+        });
+      }
+    } catch (error) {
+      logger.error('alertAdminsIfSensitive failed', {
+        error:  error instanceof Error ? error.message : String(error),
+        action: entry.action,
+      });
+    }
+  }
+
  // -------------------------------------------------------------------------
  // Query — admin UI
  // -------------------------------------------------------------------------
--- a/backend/src/services/events.service.ts
+++ b/backend/src/services/events.service.ts
@@ -614,6 +614,48 @@ class EventsService {
    }));
  }

+  // -------------------------------------------------------------------------
+  // CONFLICT CHECK
+  // -------------------------------------------------------------------------
+
+  /**
+   * Returns events that overlap with the given time range.
+   * Used to warn users about scheduling conflicts before creating/updating events.
+   */
+  async checkConflicts(
+    datumVon: Date,
+    datumBis: Date,
+    excludeId?: string
+  ): Promise<Array<{ id: string; titel: string; datum_von: Date; datum_bis: Date; kategorie_name: string | null }>> {
+    const params: any[] = [datumVon, datumBis];
+    let excludeClause = '';
+    if (excludeId) {
+      excludeClause = ' AND v.id != $3';
+      params.push(excludeId);
+    }
+
+    const result = await pool.query(
+      `SELECT v.id, v.titel, v.datum_von, v.datum_bis,
+              k.name AS kategorie_name
+       FROM veranstaltungen v
+       LEFT JOIN veranstaltung_kategorien k ON k.id = v.kategorie_id
+       WHERE v.abgesagt = FALSE
+         AND ($1::timestamptz, $2::timestamptz) OVERLAPS (v.datum_von, v.datum_bis)
+         ${excludeClause}
+       ORDER BY v.datum_von ASC
+       LIMIT 10`,
+      params
+    );
+
+    return result.rows.map((row) => ({
+      id: row.id,
+      titel: row.titel,
+      datum_von: new Date(row.datum_von),
+      datum_bis: new Date(row.datum_bis),
+      kategorie_name: row.kategorie_name ?? null,
+    }));
+  }
+
  // -------------------------------------------------------------------------
  // ICAL EXPORT
  // -------------------------------------------------------------------------
--- a/backend/src/services/vehicle.service.ts
+++ b/backend/src/services/vehicle.service.ts
@@ -406,6 +406,43 @@ class VehicleService {
    }
  }

+  // =========================================================================
+  // MAINTENANCE WINDOWS (for booking calendar overlay)
+  // =========================================================================
+
+  async getMaintenanceWindows(
+    from: Date,
+    to: Date
+  ): Promise<
+    {
+      id: string;
+      bezeichnung: string;
+      kurzname: string | null;
+      status: string;
+      status_bemerkung: string | null;
+      ausser_dienst_von: string;
+      ausser_dienst_bis: string;
+    }[]
+  > {
+    try {
+      const result = await pool.query(
+        `SELECT id, bezeichnung, kurzname, status, status_bemerkung,
+                ausser_dienst_von, ausser_dienst_bis
+         FROM fahrzeuge
+         WHERE deleted_at IS NULL
+           AND status IN ('ausser_dienst_wartung', 'ausser_dienst_schaden')
+           AND ausser_dienst_von IS NOT NULL
+           AND ausser_dienst_bis IS NOT NULL
+           AND (ausser_dienst_von, ausser_dienst_bis) OVERLAPS ($1, $2)`,
+        [from, to]
+      );
+      return result.rows;
+    } catch (error) {
+      logger.error('VehicleService.getMaintenanceWindows failed', { error });
+      throw new Error('Failed to fetch maintenance windows');
+    }
+  }
+
  // =========================================================================
  // DASHBOARD KPI
  // =========================================================================
--- a/frontend/src/components/admin/NotificationBroadcastTab.tsx
+++ b/frontend/src/components/admin/NotificationBroadcastTab.tsx
@@ -1,4 +1,4 @@
-import { useState } from 'react';
+import { useState, useEffect, useRef, useCallback } from 'react';
 import {
  Box,
  TextField,
@@ -11,20 +11,49 @@ import {
  DialogContentText,
  DialogActions,
  CircularProgress,
+  FormControlLabel,
+  Checkbox,
+  Chip,
+  OutlinedInput,
+  InputLabel,
+  FormControl,
+  Select,
 } from '@mui/material';
+import type { SelectChangeEvent } from '@mui/material';
 import SendIcon from '@mui/icons-material/Send';
+import PeopleIcon from '@mui/icons-material/People';
 import { useMutation } from '@tanstack/react-query';
 import { adminApi } from '../../services/admin';
 import { useNotification } from '../../contexts/NotificationContext';
 import type { BroadcastPayload } from '../../types/admin.types';

+const DIENSTGRAD_OPTIONS = [
+  'Mitglied',
+  'Maschinist',
+  'Truppführer',
+  'Gruppenführer',
+  'Zugkommandant',
+  'Kommandant',
+];
+
+const GROUP_OPTIONS = [
+  'dashboard_admin',
+  'dashboard_kommando',
+  'dashboard_gruppenfuehrer',
+];
+
 function NotificationBroadcastTab() {
  const { showSuccess, showError } = useNotification();
  const [titel, setTitel] = useState('');
  const [nachricht, setNachricht] = useState('');
  const [schwere, setSchwere] = useState<'info' | 'warnung' | 'fehler'>('info');
  const [targetGroup, setTargetGroup] = useState('');
+  const [targetDienstgrad, setTargetDienstgrad] = useState<string[]>([]);
+  const [alleBenutzer, setAlleBenutzer] = useState(true);
  const [confirmOpen, setConfirmOpen] = useState(false);
+  const [previewCount, setPreviewCount] = useState<number | null>(null);
+  const [previewLoading, setPreviewLoading] = useState(false);
+  const debounceRef = useRef<ReturnType<typeof setTimeout> | null>(null);

  const broadcastMutation = useMutation({
    mutationFn: (data: BroadcastPayload) => adminApi.broadcast(data),
@@ -34,26 +63,74 @@ function NotificationBroadcastTab() {
      setNachricht('');
      setSchwere('info');
      setTargetGroup('');
+      setTargetDienstgrad([]);
+      setAlleBenutzer(true);
+      setPreviewCount(null);
    },
    onError: () => {
      showError('Fehler beim Senden der Benachrichtigung');
    },
  });

+  const fetchPreview = useCallback(() => {
+    if (alleBenutzer) {
+      // For "Alle Benutzer" we still fetch the count (no filters)
+      setPreviewLoading(true);
+      adminApi.broadcastPreview({})
+        .then((result) => setPreviewCount(result.count))
+        .catch(() => setPreviewCount(null))
+        .finally(() => setPreviewLoading(false));
+      return;
+    }
+
+    const payload: { targetGroup?: string; targetDienstgrad?: string[] } = {};
+    if (targetGroup.trim()) payload.targetGroup = targetGroup.trim();
+    if (targetDienstgrad.length > 0) payload.targetDienstgrad = targetDienstgrad;
+
+    setPreviewLoading(true);
+    adminApi.broadcastPreview(payload)
+      .then((result) => setPreviewCount(result.count))
+      .catch(() => setPreviewCount(null))
+      .finally(() => setPreviewLoading(false));
+  }, [alleBenutzer, targetGroup, targetDienstgrad]);
+
+  useEffect(() => {
+    if (debounceRef.current) clearTimeout(debounceRef.current);
+    debounceRef.current = setTimeout(fetchPreview, 300);
+    return () => {
+      if (debounceRef.current) clearTimeout(debounceRef.current);
+    };
+  }, [fetchPreview]);
+
  const handleSubmit = () => {
    setConfirmOpen(true);
  };

  const handleConfirm = () => {
    setConfirmOpen(false);
-    broadcastMutation.mutate({
-      titel,
-      nachricht,
-      schwere,
-      ...(targetGroup.trim() ? { targetGroup: targetGroup.trim() } : {}),
-    });
+    const payload: BroadcastPayload = { titel, nachricht, schwere };
+    if (!alleBenutzer) {
+      if (targetGroup.trim()) payload.targetGroup = targetGroup.trim();
+      if (targetDienstgrad.length > 0) payload.targetDienstgrad = targetDienstgrad;
+    }
+    broadcastMutation.mutate(payload);
  };

+  const handleDienstgradChange = (event: SelectChangeEvent<string[]>) => {
+    const value = event.target.value;
+    setTargetDienstgrad(typeof value === 'string' ? value.split(',') : value);
+  };
+
+  const filtersActive = !alleBenutzer && (targetGroup.trim() || targetDienstgrad.length > 0);
+
+  const filterDescription = (() => {
+    if (alleBenutzer) return 'alle aktiven Benutzer';
+    const parts: string[] = [];
+    if (targetGroup.trim()) parts.push(`Gruppe "${targetGroup.trim()}"`);
+    if (targetDienstgrad.length > 0) parts.push(`Dienstgrad: ${targetDienstgrad.join(', ')}`);
+    return parts.length > 0 ? parts.join(' + ') : 'alle aktiven Benutzer';
+  })();
+
  return (
    <Box sx={{ maxWidth: 600 }}>
      <Typography variant="h6" sx={{ mb: 2 }}>Benachrichtigung senden</Typography>
@@ -91,15 +168,77 @@ function NotificationBroadcastTab() {
        <MenuItem value="fehler">Fehler</MenuItem>
      </TextField>

-      <TextField
-        label="Zielgruppe (optional)"
-        fullWidth
-        value={targetGroup}
-        onChange={(e) => setTargetGroup(e.target.value)}
-        helperText="Leer lassen um an alle aktiven Benutzer zu senden"
-        sx={{ mb: 3 }}
+      <FormControlLabel
+        control={
+          <Checkbox
+            checked={alleBenutzer}
+            onChange={(e) => {
+              setAlleBenutzer(e.target.checked);
+              if (e.target.checked) {
+                setTargetGroup('');
+                setTargetDienstgrad([]);
+              }
+            }}
+          />
+        }
+        label="Alle Benutzer"
+        sx={{ mb: 2, display: 'block' }}
      />

+      {!alleBenutzer && (
+        <>
+          <TextField
+            select
+            label="Authentik-Gruppe"
+            fullWidth
+            value={targetGroup}
+            onChange={(e) => setTargetGroup(e.target.value)}
+            sx={{ mb: 2 }}
+          >
+            <MenuItem value="">
+              <em>Keine Einschraenkung</em>
+            </MenuItem>
+            {GROUP_OPTIONS.map((g) => (
+              <MenuItem key={g} value={g}>{g}</MenuItem>
+            ))}
+          </TextField>
+
+          <FormControl fullWidth sx={{ mb: 2 }}>
+            <InputLabel>Dienstgrad</InputLabel>
+            <Select
+              multiple
+              value={targetDienstgrad}
+              onChange={handleDienstgradChange}
+              input={<OutlinedInput label="Dienstgrad" />}
+              renderValue={(selected) => (
+                <Box sx={{ display: 'flex', flexWrap: 'wrap', gap: 0.5 }}>
+                  {selected.map((value) => (
+                    <Chip key={value} label={value} size="small" />
+                  ))}
+                </Box>
+              )}
+            >
+              {DIENSTGRAD_OPTIONS.map((d) => (
+                <MenuItem key={d} value={d}>{d}</MenuItem>
+              ))}
+            </Select>
+          </FormControl>
+        </>
+      )}
+
+      <Box sx={{ mb: 3, display: 'flex', alignItems: 'center', gap: 1 }}>
+        <PeopleIcon color="action" fontSize="small" />
+        {previewLoading ? (
+          <CircularProgress size={16} />
+        ) : (
+          <Typography variant="body2" color="text.secondary">
+            {previewCount !== null
+              ? `Wird an ${previewCount} Benutzer gesendet`
+              : 'Empfaengeranzahl wird geladen...'}
+          </Typography>
+        )}
+      </Box>
+
      <Button
        variant="contained"
        startIcon={broadcastMutation.isPending ? <CircularProgress size={18} color="inherit" /> : <SendIcon />}
@@ -113,8 +252,10 @@ function NotificationBroadcastTab() {
        <DialogTitle>Benachrichtigung senden?</DialogTitle>
        <DialogContent>
          <DialogContentText>
-            Sind Sie sicher, dass Sie diese Benachrichtigung
-            {targetGroup.trim() ? ` an die Gruppe "${targetGroup.trim()}"` : ' an alle aktiven Benutzer'} senden moechten?
+            Sind Sie sicher, dass Sie diese Benachrichtigung an {filterDescription} senden moechten?
+            {previewCount !== null && (
+              <> ({previewCount} {previewCount === 1 ? 'Empfaenger' : 'Empfaenger'})</>
+            )}
          </DialogContentText>
        </DialogContent>
        <DialogActions>
--- a/frontend/src/components/dashboard/AtemschutzExpiryNotifier.tsx
+++ b/frontend/src/components/dashboard/AtemschutzExpiryNotifier.tsx
@@ -0,0 +1,20 @@
+import React from 'react';
+import { useQuery } from '@tanstack/react-query';
+import { atemschutzApi } from '../../services/atemschutz';
+
+/**
+ * Invisible component — polls /api/atemschutz/expiring every 10 minutes.
+ * The backend creates notifications as a side-effect when polled.
+ */
+const AtemschutzExpiryNotifier: React.FC = () => {
+  useQuery({
+    queryKey: ['atemschutz-expiring'],
+    queryFn: () => atemschutzApi.getExpiring(),
+    refetchInterval: 10 * 60 * 1000,
+    retry: 1,
+  });
+
+  return null;
+};
+
+export default AtemschutzExpiryNotifier;
--- a/frontend/src/components/dashboard/index.ts
+++ b/frontend/src/components/dashboard/index.ts
@@ -9,6 +9,7 @@ export { default as BookStackSearchWidget } from './BookStackSearchWidget';
 export { default as VikunjaMyTasksWidget } from './VikunjaMyTasksWidget';
 export { default as VikunjaQuickAddWidget } from './VikunjaQuickAddWidget';
 export { default as VikunjaOverdueNotifier } from './VikunjaOverdueNotifier';
+export { default as AtemschutzExpiryNotifier } from './AtemschutzExpiryNotifier';
 export { default as AdminStatusWidget } from './AdminStatusWidget';
 export { default as VehicleBookingListWidget } from './VehicleBookingListWidget';
 export { default as VehicleBookingQuickAddWidget } from './VehicleBookingQuickAddWidget';
--- a/frontend/src/pages/Dashboard.tsx
+++ b/frontend/src/pages/Dashboard.tsx
@@ -18,6 +18,7 @@ import BookStackSearchWidget from '../components/dashboard/BookStackSearchWidget
 import VikunjaMyTasksWidget from '../components/dashboard/VikunjaMyTasksWidget';
 import VikunjaQuickAddWidget from '../components/dashboard/VikunjaQuickAddWidget';
 import VikunjaOverdueNotifier from '../components/dashboard/VikunjaOverdueNotifier';
+import AtemschutzExpiryNotifier from '../components/dashboard/AtemschutzExpiryNotifier';
 import AdminStatusWidget from '../components/dashboard/AdminStatusWidget';
 import AnnouncementBanner from '../components/dashboard/AnnouncementBanner';
 import VehicleBookingQuickAddWidget from '../components/dashboard/VehicleBookingQuickAddWidget';
@@ -72,6 +73,8 @@ function Dashboard() {
    <DashboardLayout>
      {/* Vikunja — Overdue Notifier (invisible, polling component — outside grid) */}
      <VikunjaOverdueNotifier />
+      {/* Atemschutz — Expiry Notifier (invisible, polling component — outside grid) */}
+      <AtemschutzExpiryNotifier />
      <Container maxWidth={false} disableGutters>
        <Box
          sx={{
--- a/frontend/src/pages/FahrzeugBuchungen.tsx
+++ b/frontend/src/pages/FahrzeugBuchungen.tsx
@@ -41,6 +41,7 @@ import {
  CheckCircle,
  Warning,
  Block,
+  Build,
 } from '@mui/icons-material';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
 import ChatAwareFab from '../components/shared/ChatAwareFab';
@@ -52,6 +53,7 @@ import type {
  Fahrzeug,
  CreateBuchungInput,
  BuchungsArt,
+  MaintenanceWindow,
 } from '../types/booking.types';
 import { BUCHUNGS_ART_LABELS, BUCHUNGS_ART_COLORS } from '../types/booking.types';
 import {
@@ -116,6 +118,7 @@ function FahrzeugBuchungen() {
  // ── Data ──────────────────────────────────────────────────────────────────
  const [vehicles, setVehicles] = useState<Fahrzeug[]>([]);
  const [bookings, setBookings] = useState<FahrzeugBuchungListItem[]>([]);
+  const [maintenanceWindows, setMaintenanceWindows] = useState<MaintenanceWindow[]>([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);

@@ -123,12 +126,13 @@ function FahrzeugBuchungen() {
    setLoading(true);
    try {
      const end = endOfWeek(currentWeekStart, { weekStartsOn: 1 });
-      const [vehiclesData, bookingsData] = await Promise.all([
+      const [vehiclesData, calendarData] = await Promise.all([
        fetchVehicles(),
        bookingApi.getCalendarRange(currentWeekStart, end),
      ]);
      setVehicles(vehiclesData);
-      setBookings(bookingsData);
+      setBookings(calendarData.bookings);
+      setMaintenanceWindows(calendarData.maintenanceWindows);
      setError(null);
    } catch (e: unknown) {
      const msg = e instanceof Error ? e.message : 'Fehler beim Laden';
@@ -160,6 +164,22 @@ function FahrzeugBuchungen() {
  };

  const isOutOfService = (vehicle: Fahrzeug, day: Date): boolean => {
+    // Check from maintenance windows (server-side filtered)
+    const mw = maintenanceWindows.find((w) => w.id === vehicle.id);
+    if (mw) {
+      try {
+        if (
+          isWithinInterval(day, {
+            start: parseISO(mw.ausser_dienst_von),
+            end: parseISO(mw.ausser_dienst_bis),
+          })
+        )
+          return true;
+      } catch {
+        /* ignore parse errors */
+      }
+    }
+    // Fallback to vehicle-level dates
    if (!vehicle.ausser_dienst_von || !vehicle.ausser_dienst_bis) return false;
    try {
      return isWithinInterval(day, {
@@ -171,6 +191,29 @@ function FahrzeugBuchungen() {
    }
  };

+  /** Get the maintenance tooltip text for an out-of-service cell */
+  const getMaintenanceTooltip = (vehicle: Fahrzeug): string => {
+    const mw = maintenanceWindows.find((w) => w.id === vehicle.id);
+    const statusLabel =
+      (mw?.status ?? vehicle.status) === 'ausser_dienst_wartung'
+        ? 'Wartung'
+        : 'Schaden';
+    const bemerkung = mw?.status_bemerkung ?? vehicle.status_bemerkung;
+    const von = mw?.ausser_dienst_von ?? vehicle.ausser_dienst_von;
+    const bis = mw?.ausser_dienst_bis ?? vehicle.ausser_dienst_bis;
+
+    let tooltip = `Außer Dienst (${statusLabel})`;
+    if (bemerkung) tooltip += `: ${bemerkung}`;
+    if (von && bis) {
+      try {
+        tooltip += `\n${format(parseISO(von), 'dd.MM.yyyy')} – ${format(parseISO(bis), 'dd.MM.yyyy')}`;
+      } catch {
+        /* ignore */
+      }
+    }
+    return tooltip;
+  };
+
  // ── Create / Edit dialog ──────────────────────────────────────────────────
  const [dialogOpen, setDialogOpen] = useState(false);
  const [editingBooking, setEditingBooking] =
@@ -485,9 +528,15 @@ function FahrzeugBuchungen() {
                          }}
                        >
                          {oos && (
-                            <Tooltip title="Fahrzeug außer Dienst">
+                            <Tooltip
+                              title={
+                                <span style={{ whiteSpace: 'pre-line' }}>
+                                  {getMaintenanceTooltip(vehicle)}
+                                </span>
+                              }
+                            >
                              <Chip
-                                icon={<Block fontSize="small" />}
+                                icon={<Build fontSize="small" />}
                                label="Außer Dienst"
                                size="small"
                                color="error"
@@ -570,9 +619,14 @@ function FahrzeugBuchungen() {
                  border: '1px solid',
                  borderColor: (theme) => theme.palette.mode === 'dark' ? 'error.700' : 'error.300',
                  borderRadius: 0.5,
+                  display: 'flex',
+                  alignItems: 'center',
+                  justifyContent: 'center',
                }}
-              />
-              <Typography variant="caption">Außer Dienst</Typography>
+              >
+                <Build sx={{ fontSize: 10, color: 'error.main' }} />
+              </Box>
+              <Typography variant="caption">Außer Dienst (Wartung/Schaden)</Typography>
            </Box>
            {(Object.entries(BUCHUNGS_ART_LABELS) as [BuchungsArt, string][]).map(
              ([art, label]) => (
--- a/frontend/src/pages/Fahrzeuge.tsx
+++ b/frontend/src/pages/Fahrzeuge.tsx
@@ -2,6 +2,7 @@ import React, { useEffect, useState, useCallback } from 'react';
 import {
  Alert,
  Box,
+  Button,
  Card,
  CardActionArea,
  CardContent,
@@ -20,6 +21,7 @@ import {
  CheckCircle,
  DirectionsCar,
  Error as ErrorIcon,
+  FileDownload,
  PauseCircle,
  School,
  Search,
@@ -328,6 +330,24 @@ function Fahrzeuge() {
    fetchWarnings();
  }, []);

+  const handleExportAlerts = useCallback(async () => {
+    try {
+      const blob = await vehiclesApi.exportAlerts();
+      const url = URL.createObjectURL(blob);
+      const a = document.createElement('a');
+      a.href = url;
+      const today = new Date();
+      const dateStr = `${today.getFullYear()}-${String(today.getMonth() + 1).padStart(2, '0')}-${String(today.getDate()).padStart(2, '0')}`;
+      a.download = `pruefungen_${dateStr}.csv`;
+      document.body.appendChild(a);
+      a.click();
+      a.remove();
+      URL.revokeObjectURL(url);
+    } catch {
+      setError('CSV-Export fehlgeschlagen.');
+    }
+  }, []);
+
  const filtered = vehicles.filter((v) => {
    if (!search.trim()) return true;
    const q = search.toLowerCase();
@@ -366,6 +386,14 @@ function Fahrzeuge() {
              </Typography>
            )}
          </Box>
+          <Button
+            variant="outlined"
+            size="small"
+            startIcon={<FileDownload />}
+            onClick={handleExportAlerts}
+          >
+            Prüfungen CSV
+          </Button>
        </Box>

        {hasOverdue && (
--- a/frontend/src/pages/Veranstaltungen.tsx
+++ b/frontend/src/pages/Veranstaltungen.tsx
@@ -1,4 +1,4 @@
-import { useState, useEffect, useCallback, useMemo } from 'react';
+import { useState, useEffect, useCallback, useMemo, useRef } from 'react';
 import {
  Box,
  Typography,
@@ -60,6 +60,7 @@ import type {
  VeranstaltungKategorie,
  GroupInfo,
  CreateVeranstaltungInput,
+  ConflictEvent,
 } from '../types/events.types';

 // ---------------------------------------------------------------------------
@@ -609,6 +610,46 @@ function EventFormDialog({
    }
  }, [open, editingEvent]);

+  // -----------------------------------------------------------------------
+  // Conflict detection — debounced check when dates change
+  // -----------------------------------------------------------------------
+  const [conflicts, setConflicts] = useState<ConflictEvent[]>([]);
+  const conflictTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null);
+
+  useEffect(() => {
+    // Clear conflicts when dialog closes
+    if (!open) {
+      setConflicts([]);
+      return;
+    }
+
+    const vonDate = new Date(form.datum_von);
+    const bisDate = new Date(form.datum_bis);
+    if (isNaN(vonDate.getTime()) || isNaN(bisDate.getTime()) || bisDate <= vonDate) {
+      setConflicts([]);
+      return;
+    }
+
+    if (conflictTimerRef.current) clearTimeout(conflictTimerRef.current);
+    conflictTimerRef.current = setTimeout(async () => {
+      try {
+        const result = await eventsApi.checkConflicts(
+          vonDate.toISOString(),
+          bisDate.toISOString(),
+          editingEvent?.id
+        );
+        setConflicts(result);
+      } catch {
+        // Silently ignore — conflict check is advisory only
+        setConflicts([]);
+      }
+    }, 500);
+
+    return () => {
+      if (conflictTimerRef.current) clearTimeout(conflictTimerRef.current);
+    };
+  }, [open, form.datum_von, form.datum_bis, editingEvent]);
+
  const handleChange = (field: keyof CreateVeranstaltungInput, value: unknown) => {
    if (field === 'kategorie_id' && !editingEvent) {
      // Auto-fill zielgruppen / alle_gruppen from the selected category (only for new events)
@@ -771,6 +812,31 @@ function EventFormDialog({
            fullWidth
          />

+          {/* Conflict warning */}
+          {conflicts.length > 0 && (
+            <Alert severity="warning" sx={{ mt: 0 }}>
+              <Typography variant="body2" fontWeight={600} sx={{ mb: 0.5 }}>
+                Überschneidung mit bestehenden Veranstaltungen:
+              </Typography>
+              {conflicts.map((c) => {
+                const von = new Date(c.datum_von);
+                const bis = new Date(c.datum_bis);
+                const fmtDate = (d: Date) =>
+                  `${String(d.getDate()).padStart(2, '0')}.${String(d.getMonth() + 1).padStart(2, '0')}.${d.getFullYear()}`;
+                const fmtTime = (d: Date) =>
+                  `${String(d.getHours()).padStart(2, '0')}:${String(d.getMinutes()).padStart(2, '0')}`;
+                const range = sameDay(von, bis)
+                  ? `${fmtDate(von)} ${fmtTime(von)} - ${fmtTime(bis)}`
+                  : `${fmtDate(von)} ${fmtTime(von)} - ${fmtDate(bis)} ${fmtTime(bis)}`;
+                return (
+                  <Typography key={c.id} variant="body2">
+                    {'\u2022'} &quot;{c.titel}&quot; ({range})
+                  </Typography>
+                );
+              })}
+            </Alert>
+          )}
+
          {/* Ort */}
          <TextField
            label="Ort"
--- a/frontend/src/services/admin.ts
+++ b/frontend/src/services/admin.ts
@@ -1,5 +1,5 @@
 import { api } from './api';
-import type { MonitoredService, PingResult, PingHistoryEntry, StatusSummary, SystemHealth, UserOverview, BroadcastPayload } from '../types/admin.types';
+import type { MonitoredService, PingResult, PingHistoryEntry, StatusSummary, SystemHealth, UserOverview, BroadcastPayload, BroadcastPreviewPayload } from '../types/admin.types';

 interface ApiResponse<T> {
  success: boolean;
@@ -26,6 +26,7 @@ export const adminApi = {
  getSystemHealth: () => api.get<ApiResponse<SystemHealth>>('/api/admin/system/health').then(r => r.data.data),
  getUsers: () => api.get<ApiResponse<UserOverview[]>>('/api/admin/users').then(r => r.data.data),
  broadcast: (data: BroadcastPayload) => api.post<ApiResponse<{ sent: number }>>('/api/admin/notifications/broadcast', data).then(r => r.data.data),
+  broadcastPreview: (data: BroadcastPreviewPayload) => api.post<ApiResponse<{ count: number }>>('/api/admin/notifications/broadcast/preview', data).then(r => r.data.data),
  getPingHistory: (serviceId: string) => api.get<ApiResponse<PingHistoryEntry[]>>(`/api/admin/services/${serviceId}/ping-history`).then(r => r.data.data),
  fdiskSyncLogs: () => api.get<ApiResponse<FdiskSyncLogsResponse>>('/api/admin/fdisk-sync/logs').then(r => r.data.data),
  fdiskSyncTrigger: (force = false) => api.post<ApiResponse<{ started: boolean }>>('/api/admin/fdisk-sync/trigger', { force }).then(r => r.data.data),
--- a/frontend/src/services/atemschutz.ts
+++ b/frontend/src/services/atemschutz.ts
@@ -76,4 +76,9 @@ export const atemschutzApi = {
  async delete(id: string): Promise<void> {
    await api.delete(`/api/atemschutz/${id}`);
  },
+
+  async getExpiring(): Promise<any[]> {
+    const response = await api.get<{ success: boolean; data: any[] }>('/api/atemschutz/expiring');
+    return response.data?.data ?? [];
+  },
 };
--- a/frontend/src/services/bookings.ts
+++ b/frontend/src/services/bookings.ts
@@ -4,6 +4,7 @@ import type {
  FahrzeugBuchung,
  Fahrzeug,
  CreateBuchungInput,
+  MaintenanceWindow,
 } from '../types/booking.types';

 // ---------------------------------------------------------------------------
@@ -22,15 +23,22 @@ export const bookingApi = {
  // Calendar / listing
  // -------------------------------------------------------------------------

-  getCalendarRange(from: Date, to: Date, fahrzeugId?: string): Promise<FahrzeugBuchungListItem[]> {
+  getCalendarRange(
+    from: Date,
+    to: Date,
+    fahrzeugId?: string
+  ): Promise<{ bookings: FahrzeugBuchungListItem[]; maintenanceWindows: MaintenanceWindow[] }> {
    return api
-      .get<ApiResponse<FahrzeugBuchungListItem[]>>('/api/bookings/calendar', {
-        params: {
-          from: from.toISOString(),
-          to: to.toISOString(),
-          ...(fahrzeugId ? { fahrzeugId } : {}),
-        },
-      })
+      .get<ApiResponse<{ bookings: FahrzeugBuchungListItem[]; maintenanceWindows: MaintenanceWindow[] }>>(
+        '/api/bookings/calendar',
+        {
+          params: {
+            from: from.toISOString(),
+            to: to.toISOString(),
+            ...(fahrzeugId ? { fahrzeugId } : {}),
+          },
+        }
+      )
      .then((r) => r.data.data);
  },

--- a/frontend/src/services/events.ts
+++ b/frontend/src/services/events.ts
@@ -5,6 +5,7 @@ import type {
  Veranstaltung,
  GroupInfo,
  CreateVeranstaltungInput,
+  ConflictEvent,
 } from '../types/events.types';

 // ---------------------------------------------------------------------------
@@ -153,4 +154,13 @@ export const eventsApi = {
      .post<ApiResponse<{ created: number; errors: string[] }>>('/api/events/import', { events })
      .then((r) => r.data.data);
  },
+
+  /** Check for overlapping events in a time range */
+  checkConflicts(from: string, to: string, excludeId?: string): Promise<ConflictEvent[]> {
+    return api
+      .get<ApiResponse<ConflictEvent[]>>('/api/events/conflicts', {
+        params: { from, to, ...(excludeId ? { excludeId } : {}) },
+      })
+      .then((r) => r.data.data);
+  },
 };
--- a/frontend/src/services/vehicles.ts
+++ b/frontend/src/services/vehicles.ts
@@ -93,4 +93,11 @@ export const vehiclesApi = {
    }
    return response.data.data;
  },
+
+  async exportAlerts(): Promise<Blob> {
+    const response = await api.get('/api/vehicles/alerts/export', {
+      responseType: 'blob',
+    });
+    return response.data as Blob;
+  },
 };
--- a/frontend/src/types/admin.types.ts
+++ b/frontend/src/types/admin.types.ts
@@ -58,4 +58,10 @@ export interface BroadcastPayload {
  nachricht: string;
  schwere?: 'info' | 'warnung' | 'fehler';
  targetGroup?: string;
+  targetDienstgrad?: string[];
+}
+
+export interface BroadcastPreviewPayload {
+  targetGroup?: string;
+  targetDienstgrad?: string[];
 }
--- a/frontend/src/types/booking.types.ts
+++ b/frontend/src/types/booking.types.ts
@@ -47,10 +47,21 @@ export interface Fahrzeug {
  kurzname: string | null;
  amtliches_kennzeichen: string | null;
  status: string;
+  status_bemerkung?: string | null;
  ausser_dienst_von: string | null;
  ausser_dienst_bis: string | null;
 }

+export interface MaintenanceWindow {
+  id: string;
+  bezeichnung: string;
+  kurzname: string | null;
+  status: string;
+  status_bemerkung: string | null;
+  ausser_dienst_von: string;
+  ausser_dienst_bis: string;
+}
+
 export interface CreateBuchungInput {
  fahrzeugId: string;
  titel: string;
--- a/frontend/src/types/events.types.ts
+++ b/frontend/src/types/events.types.ts
@@ -76,3 +76,11 @@ export interface CreateVeranstaltungInput {
  anmeldung_bis?: string | null;
  wiederholung?: WiederholungConfig | null;
 }
+
+export interface ConflictEvent {
+  id: string;
+  titel: string;
+  datum_von: string; // ISO
+  datum_bis: string; // ISO
+  kategorie_name: string | null;
+}