fixed user deletion

frontend/src/contexts/NotificationContext.tsx

@@ -0,0 +1,94 @@
+// frontend/src/contexts/NotificationContext.tsx
+import React, { createContext, useContext, useState } from 'react';
+
+export type NotificationType = 'info' | 'success' | 'warning' | 'error';
+
+export interface Notification {
+  id: string;
+  type: NotificationType;
+  title: string;
+  message: string;
+  duration?: number;
+}
+
+interface NotificationContextType {
+  notifications: Notification[];
+  showNotification: (notification: Omit<Notification, 'id'>) => void;
+  removeNotification: (id: string) => void;
+  confirmDialog: (options: ConfirmDialogOptions) => Promise<boolean>;
+}
+
+interface ConfirmDialogOptions {
+  title: string;
+  message: string;
+  confirmText?: string;
+  cancelText?: string;
+  type?: NotificationType;
+}
+
+const NotificationContext = createContext<NotificationContextType | undefined>(undefined);
+
+export const NotificationProvider: React.FC<{ children: React.ReactNode }> = ({ children }) => {
+  const [notifications, setNotifications] = useState<Notification[]>([]);
+
+  const showNotification = (notification: Omit<Notification, 'id'>) => {
+    const id = Date.now().toString();
+    const newNotification: Notification = {
+      id,
+      duration: 5000,
+      ...notification
+    };
+
+    setNotifications(prev => [...prev, newNotification]);
+
+    // Auto-remove after duration
+    if (newNotification.duration) {
+      setTimeout(() => {
+        removeNotification(id);
+      }, newNotification.duration);
+    }
+  };
+
+  const removeNotification = (id: string) => {
+    setNotifications(prev => prev.filter(notif => notif.id !== id));
+  };
+
+  const confirmDialog = (options: ConfirmDialogOptions): Promise<boolean> => {
+    return new Promise((resolve) => {
+      const {
+        title,
+        message,
+        confirmText = 'OK',
+        cancelText = 'Abbrechen',
+        type = 'warning'
+      } = options;
+
+      const userConfirmed = window.confirm(
+        `${title}\n\n${message}\n\n${confirmText} / ${cancelText}`
+      );
+
+      resolve(userConfirmed);
+    });
+  };
+
+  const value = {
+    notifications,
+    showNotification,
+    removeNotification,
+    confirmDialog
+  };
+
+  return (
+    <NotificationContext.Provider value={value}>
+      {children}
+    </NotificationContext.Provider>
+  );
+};
+
+export const useNotification = () => {
+  const context = useContext(NotificationContext);
+  if (context === undefined) {
+    throw new Error('useNotification must be used within a NotificationProvider');
+  }
+  return context;
+};