import axios from 'axios';
import type { ApiResponse, Customer, Contract, ContractTask, ContractTaskSubtask, ContractTaskStatus, SalesPlatform, CancellationPeriod, ContractDuration, ContractCategory, Provider, Tariff, User, Address, BankCard, IdentityDocument, Meter, MeterReading, Invoice, Role, PortalSettings, CustomerRepresentative, CustomerSummary } from '../types';

const api = axios.create({
  baseURL: '/api',
  headers: {
    'Content-Type': 'application/json',
  },
});

// Add auth token to requests
api.interceptors.request.use((config) => {
  const token = localStorage.getItem('token');
  if (token) {
    config.headers.Authorization = `Bearer ${token}`;
  }
  return config;
});

// Handle auth errors and extract error messages
api.interceptors.response.use(
  (response) => response,
  (error) => {
    // Bei 401 nur dann zur Login-Seite umleiten, wenn wir NICHT gerade auf der Login-Seite sind
    // Login-Endpunkte ausschließen, da 401 dort "falsches Passwort" bedeutet
    const isLoginEndpoint = error.config?.url?.includes('/auth/login') ||
                            error.config?.url?.includes('/auth/customer-login');

    if (error.response?.status === 401 && !isLoginEndpoint) {
      localStorage.removeItem('token');
      localStorage.removeItem('user');
      window.location.href = '/login';
    }
    // Extract error message from response
    const message = error.response?.data?.error || error.message || 'Ein Fehler ist aufgetreten';
    const enhancedError = new Error(message);
    return Promise.reject(enhancedError);
  }
);

// Auth
export const authApi = {
  login: async (email: string, password: string) => {
    const res = await api.post<ApiResponse<{ token: string; user: User }>>('/auth/login', { email, password });
    return res.data;
  },
  customerLogin: async (email: string, password: string) => {
    const res = await api.post<ApiResponse<{ token: string; user: User }>>('/auth/customer-login', { email, password });
    return res.data;
  },
  me: async () => {
    const res = await api.get<ApiResponse<User>>('/auth/me');
    return res.data;
  },
};

// Customers
export const customerApi = {
  getAll: async (params?: { search?: string; type?: string; page?: number; limit?: number }) => {
    const res = await api.get<ApiResponse<Customer[]>>('/customers', { params });
    return res.data;
  },
  getById: async (id: number) => {
    const res = await api.get<ApiResponse<Customer>>(`/customers/${id}`);
    return res.data;
  },
  create: async (data: Partial<Customer>) => {
    const res = await api.post<ApiResponse<Customer>>('/customers', data);
    return res.data;
  },
  update: async (id: number, data: Partial<Customer>) => {
    const res = await api.put<ApiResponse<Customer>>(`/customers/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/customers/${id}`);
    return res.data;
  },
  // Portal-Einstellungen
  getPortalSettings: async (customerId: number) => {
    const res = await api.get<ApiResponse<PortalSettings>>(`/customers/${customerId}/portal`);
    return res.data;
  },
  updatePortalSettings: async (customerId: number, data: { portalEnabled?: boolean; portalEmail?: string | null }) => {
    const res = await api.put<ApiResponse<PortalSettings>>(`/customers/${customerId}/portal`, data);
    return res.data;
  },
  setPortalPassword: async (customerId: number, password: string) => {
    const res = await api.post<ApiResponse<void>>(`/customers/${customerId}/portal/password`, { password });
    return res.data;
  },
  getPortalPassword: async (customerId: number) => {
    const res = await api.get<ApiResponse<{ password: string | null }>>(`/customers/${customerId}/portal/password`);
    return res.data;
  },
  // Vertreter-Verwaltung
  getRepresentatives: async (customerId: number) => {
    const res = await api.get<ApiResponse<CustomerRepresentative[]>>(`/customers/${customerId}/representatives`);
    return res.data;
  },
  addRepresentative: async (customerId: number, representativeId: number, notes?: string) => {
    const res = await api.post<ApiResponse<CustomerRepresentative>>(`/customers/${customerId}/representatives`, { representativeId, notes });
    return res.data;
  },
  removeRepresentative: async (customerId: number, representativeId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/customers/${customerId}/representatives/${representativeId}`);
    return res.data;
  },
  searchForRepresentative: async (customerId: number, search: string) => {
    const res = await api.get<ApiResponse<CustomerSummary[]>>(`/customers/${customerId}/representatives/search`, { params: { search } });
    return res.data;
  },
};

// Addresses
export const addressApi = {
  getByCustomer: async (customerId: number) => {
    const res = await api.get<ApiResponse<Address[]>>(`/customers/${customerId}/addresses`);
    return res.data;
  },
  create: async (customerId: number, data: Partial<Address>) => {
    const res = await api.post<ApiResponse<Address>>(`/customers/${customerId}/addresses`, data);
    return res.data;
  },
  update: async (id: number, data: Partial<Address>) => {
    const res = await api.put<ApiResponse<Address>>(`/addresses/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/addresses/${id}`);
    return res.data;
  },
};

// Bank Cards
export const bankCardApi = {
  getByCustomer: async (customerId: number, showInactive = false) => {
    const res = await api.get<ApiResponse<BankCard[]>>(`/customers/${customerId}/bank-cards`, { params: { showInactive } });
    return res.data;
  },
  create: async (customerId: number, data: Partial<BankCard>) => {
    const res = await api.post<ApiResponse<BankCard>>(`/customers/${customerId}/bank-cards`, data);
    return res.data;
  },
  update: async (id: number, data: Partial<BankCard>) => {
    const res = await api.put<ApiResponse<BankCard>>(`/bank-cards/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/bank-cards/${id}`);
    return res.data;
  },
};

// Identity Documents
export const documentApi = {
  getByCustomer: async (customerId: number, showInactive = false) => {
    const res = await api.get<ApiResponse<IdentityDocument[]>>(`/customers/${customerId}/documents`, { params: { showInactive } });
    return res.data;
  },
  create: async (customerId: number, data: Partial<IdentityDocument>) => {
    const res = await api.post<ApiResponse<IdentityDocument>>(`/customers/${customerId}/documents`, data);
    return res.data;
  },
  update: async (id: number, data: Partial<IdentityDocument>) => {
    const res = await api.put<ApiResponse<IdentityDocument>>(`/documents/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/documents/${id}`);
    return res.data;
  },
};

// Meters
export const meterApi = {
  getByCustomer: async (customerId: number, showInactive = false) => {
    const res = await api.get<ApiResponse<Meter[]>>(`/customers/${customerId}/meters`, { params: { showInactive } });
    return res.data;
  },
  create: async (customerId: number, data: Partial<Meter>) => {
    const res = await api.post<ApiResponse<Meter>>(`/customers/${customerId}/meters`, data);
    return res.data;
  },
  update: async (id: number, data: Partial<Meter>) => {
    const res = await api.put<ApiResponse<Meter>>(`/meters/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/meters/${id}`);
    return res.data;
  },
  getReadings: async (meterId: number) => {
    const res = await api.get<ApiResponse<MeterReading[]>>(`/meters/${meterId}/readings`);
    return res.data;
  },
  addReading: async (meterId: number, data: Partial<MeterReading>) => {
    const res = await api.post<ApiResponse<MeterReading>>(`/meters/${meterId}/readings`, data);
    return res.data;
  },
  updateReading: async (meterId: number, readingId: number, data: Partial<MeterReading>) => {
    const res = await api.put<ApiResponse<MeterReading>>(`/meters/${meterId}/readings/${readingId}`, data);
    return res.data;
  },
  deleteReading: async (meterId: number, readingId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/meters/${meterId}/readings/${readingId}`);
    return res.data;
  },
};

// Invoice API
export const invoiceApi = {
  getInvoices: async (ecdId: number) => {
    const res = await api.get<ApiResponse<Invoice[]>>(`/energy-details/${ecdId}/invoices`);
    return res.data;
  },
  addInvoice: async (ecdId: number, data: Partial<Invoice>) => {
    const res = await api.post<ApiResponse<Invoice>>(`/energy-details/${ecdId}/invoices`, data);
    return res.data;
  },
  updateInvoice: async (ecdId: number, invoiceId: number, data: Partial<Invoice>) => {
    const res = await api.put<ApiResponse<Invoice>>(`/energy-details/${ecdId}/invoices/${invoiceId}`, data);
    return res.data;
  },
  deleteInvoice: async (ecdId: number, invoiceId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/energy-details/${ecdId}/invoices/${invoiceId}`);
    return res.data;
  },
  uploadDocument: async (invoiceId: number, file: File) => {
    const formData = new FormData();
    formData.append('document', file);
    const res = await api.post<ApiResponse<{ path: string; filename: string }>>(
      `/upload/invoices/${invoiceId}`,
      formData,
      { headers: { 'Content-Type': 'multipart/form-data' } }
    );
    return res.data;
  },
  deleteDocument: async (invoiceId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/upload/invoices/${invoiceId}`);
    return res.data;
  },
};

// Stressfrei-Wechseln E-Mail-Adressen
export interface StressfreiEmail {
  id: number;
  customerId: number;
  email: string;
  platform?: string;
  notes?: string;
  isActive: boolean;
  hasMailbox: boolean;
  createdAt: string;
  updatedAt: string;
}

// Mailbox-Konto (für Dropdown-Auswahl)
export interface MailboxAccount {
  id: number;
  email: string;
  notes?: string;
  hasMailbox: boolean;
  _count: {
    cachedEmails: number;
  };
}

// Gecachte E-Mail
export interface CachedEmail {
  id: number;
  stressfreiEmailId: number;
  folder: 'INBOX' | 'SENT';
  messageId: string;
  uid: number;
  subject?: string;
  fromAddress: string;
  fromName?: string;
  toAddresses: string; // JSON Array
  ccAddresses?: string; // JSON Array
  receivedAt: string;
  textBody?: string;
  htmlBody?: string;
  hasAttachments: boolean;
  attachmentNames?: string; // JSON Array
  contractId?: number;
  assignedAt?: string;
  assignedBy?: number;
  isAutoAssigned?: boolean; // true = automatisch beim Senden aus Vertrag zugeordnet
  isRead: boolean;
  isStarred: boolean;
  isDeleted: boolean;
  deletedAt?: string;
  createdAt: string;
  updatedAt: string;
  stressfreiEmail?: {
    id: number;
    email: string;
    customerId: number;
  };
  contract?: {
    id: number;
    contractNumber: string;
  } | null;
}

export interface SyncResult {
  newEmails: number;
  totalEmails: number;
}

export interface EmailAttachment {
  filename: string;
  content: string;       // Base64-kodierter Inhalt
  contentType?: string;  // MIME-Type (z.B. 'application/pdf')
}

export interface SendEmailParams {
  to: string | string[];
  cc?: string | string[];
  subject: string;
  text?: string;
  html?: string;
  inReplyTo?: string;
  references?: string[];
  attachments?: EmailAttachment[];
  contractId?: number; // Vertrag dem die gesendete E-Mail zugeordnet wird
}

// Anhang-Speicher-Ziele
export interface AttachmentTargetSlot {
  key: string;
  label: string;
  field: string;
  hasDocument: boolean;
  currentPath?: string;
}

export interface AttachmentEntityWithSlots {
  id: number;
  label: string;
  slots: AttachmentTargetSlot[];
}

export interface AttachmentTargetsResponse {
  customer: {
    id: number;
    name: string;
    type: 'PRIVATE' | 'BUSINESS';
    slots: AttachmentTargetSlot[];
  };
  identityDocuments: AttachmentEntityWithSlots[];
  bankCards: AttachmentEntityWithSlots[];
  contract?: {
    id: number;
    contractNumber: string;
    type: string;
    energyDetailsId?: number;
    slots: AttachmentTargetSlot[];
  };
}

export const stressfreiEmailApi = {
  getByCustomer: async (customerId: number, includeInactive = false) => {
    const res = await api.get<ApiResponse<StressfreiEmail[]>>(`/customers/${customerId}/stressfrei-emails`, { params: { includeInactive } });
    return res.data;
  },
  create: async (customerId: number, data: {
    email: string;
    platform?: string;
    notes?: string;
    provisionAtProvider?: boolean;
    createMailbox?: boolean;
  }) => {
    const res = await api.post<ApiResponse<StressfreiEmail>>(`/customers/${customerId}/stressfrei-emails`, data);
    return res.data;
  },
  update: async (id: number, data: Partial<StressfreiEmail>) => {
    const res = await api.put<ApiResponse<StressfreiEmail>>(`/stressfrei-emails/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/stressfrei-emails/${id}`);
    return res.data;
  },
  // Mailbox nachträglich aktivieren
  enableMailbox: async (id: number) => {
    const res = await api.post<ApiResponse<null>>(`/stressfrei-emails/${id}/enable-mailbox`);
    return res.data;
  },
  // Mailbox-Status mit Provider synchronisieren
  syncMailboxStatus: async (id: number) => {
    const res = await api.post<ApiResponse<{ hasMailbox: boolean; wasUpdated: boolean }>>(`/stressfrei-emails/${id}/sync-mailbox-status`);
    return res.data;
  },
  // Mailbox-Zugangsdaten abrufen (IMAP/SMTP)
  getMailboxCredentials: async (id: number) => {
    const res = await api.get<ApiResponse<{
      email: string;
      password: string;
      imap: { server: string; port: number; encryption: string } | null;
      smtp: { server: string; port: number; encryption: string } | null;
    }>>(`/stressfrei-emails/${id}/credentials`);
    return res.data;
  },
  // Passwort zurücksetzen (generiert neues Passwort beim Provider)
  resetPassword: async (id: number) => {
    const res = await api.post<ApiResponse<{ password: string }>>(`/stressfrei-emails/${id}/reset-password`);
    return res.data;
  },
  // E-Mails synchronisieren
  syncEmails: async (id: number, fullSync = false) => {
    const res = await api.post<ApiResponse<SyncResult>>(`/stressfrei-emails/${id}/sync`, {}, { params: { full: fullSync } });
    return res.data;
  },
  // E-Mail senden
  sendEmail: async (id: number, params: SendEmailParams) => {
    const res = await api.post<ApiResponse<{ messageId: string }>>(`/stressfrei-emails/${id}/send`, params);
    return res.data;
  },
  // Ordner-Anzahlen abrufen (total und ungelesen pro Ordner)
  getFolderCounts: async (id: number) => {
    const res = await api.get<ApiResponse<{
      inbox: number;
      inboxUnread: number;
      sent: number;
      sentUnread: number;
      trash: number;
      trashUnread: number;
    }>>(`/stressfrei-emails/${id}/folder-counts`);
    return res.data;
  },
};

// Cached Email API (E-Mail-Client)
export const cachedEmailApi = {
  // E-Mails für Kunden abrufen
  getForCustomer: async (customerId: number, options?: { accountId?: number; folder?: 'INBOX' | 'SENT'; limit?: number; offset?: number }) => {
    const res = await api.get<ApiResponse<CachedEmail[]>>(`/customers/${customerId}/emails`, { params: options });
    return res.data;
  },
  // E-Mails für Vertrag abrufen
  getForContract: async (contractId: number, options?: { folder?: 'INBOX' | 'SENT'; limit?: number; offset?: number }) => {
    const res = await api.get<ApiResponse<CachedEmail[]>>(`/contracts/${contractId}/emails`, { params: options });
    return res.data;
  },
  // Ordner-Anzahlen für Vertrag abrufen (zugeordnete E-Mails)
  getContractFolderCounts: async (contractId: number) => {
    const res = await api.get<ApiResponse<{
      inbox: number;
      inboxUnread: number;
      sent: number;
      sentUnread: number;
    }>>(`/contracts/${contractId}/emails/folder-counts`);
    return res.data;
  },
  // Mailbox-Konten eines Kunden abrufen
  getMailboxAccounts: async (customerId: number) => {
    const res = await api.get<ApiResponse<MailboxAccount[]>>(`/customers/${customerId}/mailbox-accounts`);
    return res.data;
  },
  // Einzelne E-Mail abrufen (mit Body)
  getById: async (id: number) => {
    const res = await api.get<ApiResponse<CachedEmail>>(`/emails/${id}`);
    return res.data;
  },
  // E-Mail-Thread abrufen
  getThread: async (id: number) => {
    const res = await api.get<ApiResponse<CachedEmail[]>>(`/emails/${id}/thread`);
    return res.data;
  },
  // Als gelesen/ungelesen markieren
  markAsRead: async (id: number, isRead: boolean) => {
    const res = await api.patch<ApiResponse<void>>(`/emails/${id}/read`, { isRead });
    return res.data;
  },
  // Stern umschalten
  toggleStar: async (id: number) => {
    const res = await api.post<ApiResponse<{ isStarred: boolean }>>(`/emails/${id}/star`);
    return res.data;
  },
  // Vertrag zuordnen
  assignToContract: async (emailId: number, contractId: number) => {
    const res = await api.post<ApiResponse<CachedEmail>>(`/emails/${emailId}/assign`, { contractId });
    return res.data;
  },
  // Zuordnung aufheben
  unassignFromContract: async (emailId: number) => {
    const res = await api.delete<ApiResponse<CachedEmail>>(`/emails/${emailId}/assign`);
    return res.data;
  },
  // E-Mail löschen (nur Admin)
  delete: async (emailId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/emails/${emailId}`);
    return res.data;
  },
  // Anhang-URL (view=true für inline anzeigen, sonst download)
  getAttachmentUrl: (emailId: number, filename: string, view?: boolean) => {
    const token = localStorage.getItem('token');
    const encodedFilename = encodeURIComponent(filename);
    const viewParam = view ? '&view=true' : '';
    return `${api.defaults.baseURL}/emails/${emailId}/attachments/${encodedFilename}?token=${token}${viewParam}`;
  },
  // Ungelesene E-Mails zählen
  getUnreadCount: async (params: { customerId?: number; contractId?: number }) => {
    const res = await api.get<ApiResponse<{ count: number }>>('/emails/unread-count', { params });
    return res.data;
  },
  // ==================== PAPIERKORB ====================
  // Papierkorb-E-Mails für Kunden abrufen
  getTrash: async (customerId: number) => {
    const res = await api.get<ApiResponse<CachedEmail[]>>(`/customers/${customerId}/emails/trash`);
    return res.data;
  },
  // Papierkorb-Anzahl für Kunden
  getTrashCount: async (customerId: number) => {
    const res = await api.get<ApiResponse<{ count: number }>>(`/customers/${customerId}/emails/trash/count`);
    return res.data;
  },
  // E-Mail aus Papierkorb wiederherstellen
  restore: async (emailId: number) => {
    const res = await api.post<ApiResponse<void>>(`/emails/${emailId}/restore`);
    return res.data;
  },
  // E-Mail endgültig löschen (aus Papierkorb)
  permanentDelete: async (emailId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/emails/${emailId}/permanent`);
    return res.data;
  },
  // ==================== ANHANG-SPEICHERUNG ====================
  // Verfügbare Dokumenten-Ziele für Anhänge abrufen
  getAttachmentTargets: async (emailId: number) => {
    const res = await api.get<ApiResponse<AttachmentTargetsResponse>>(`/emails/${emailId}/attachment-targets`);
    return res.data;
  },
  // Anhang in Dokumentenfeld speichern
  saveAttachmentTo: async (emailId: number, filename: string, params: { entityType: string; entityId?: number; targetKey: string }) => {
    const encodedFilename = encodeURIComponent(filename);
    const res = await api.post<ApiResponse<{ path: string; filename: string; originalName: string; size: number }>>(
      `/emails/${emailId}/attachments/${encodedFilename}/save-to`,
      params
    );
    return res.data;
  },
  // E-Mail als PDF speichern
  saveEmailAsPdf: async (emailId: number, params: { entityType: string; entityId?: number; targetKey: string }) => {
    const res = await api.post<ApiResponse<{ path: string; filename: string; size: number }>>(
      `/emails/${emailId}/save-as-pdf`,
      params
    );
    return res.data;
  },
  // E-Mail als Rechnung speichern (für Energieverträge)
  saveEmailAsInvoice: async (emailId: number, params: { invoiceDate: string; invoiceType: string; notes?: string }) => {
    const res = await api.post<ApiResponse<{ id: number; invoiceDate: string; invoiceType: string; documentPath: string }>>(
      `/emails/${emailId}/save-as-invoice`,
      params
    );
    return res.data;
  },
  // Anhang als Rechnung speichern (für Energieverträge)
  saveAttachmentAsInvoice: async (emailId: number, filename: string, params: { invoiceDate: string; invoiceType: string; notes?: string }) => {
    const encodedFilename = encodeURIComponent(filename);
    const res = await api.post<ApiResponse<{ id: number; invoiceDate: string; invoiceType: string; documentPath: string }>>(
      `/emails/${emailId}/attachments/${encodedFilename}/save-as-invoice`,
      params
    );
    return res.data;
  },
};

// Contracts - Vertragsbaum für Kundenansicht
export interface ContractTreeNodeContract {
  id: number;
  contractNumber: string;
  type: string;
  status: string;
  startDate: string | null;
  endDate: string | null;
  providerName: string | null;
  tariffName: string | null;
  previousContractId: number | null;
  provider?: { id: number; name: string } | null;
  tariff?: { id: number; name: string } | null;
  contractCategory?: { id: number; name: string } | null;
}

export interface ContractTreeNode {
  contract: ContractTreeNodeContract;
  predecessors: ContractTreeNode[];
  hasHistory: boolean;
}

export const contractApi = {
  getAll: async (params?: { customerId?: number; type?: string; status?: string; search?: string; page?: number; limit?: number }) => {
    const res = await api.get<ApiResponse<Contract[]>>('/contracts', { params });
    return res.data;
  },
  getTreeForCustomer: async (customerId: number) => {
    const res = await api.get<ApiResponse<ContractTreeNode[]>>('/contracts', { params: { customerId, tree: 'true' } });
    return res.data;
  },
  getById: async (id: number) => {
    const res = await api.get<ApiResponse<Contract>>(`/contracts/${id}`);
    return res.data;
  },
  create: async (data: Partial<Contract> & { [key: string]: unknown }) => {
    const res = await api.post<ApiResponse<Contract>>('/contracts', data);
    return res.data;
  },
  update: async (id: number, data: Partial<Contract> & { [key: string]: unknown }) => {
    const res = await api.put<ApiResponse<Contract>>(`/contracts/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/contracts/${id}`);
    return res.data;
  },
  createFollowUp: async (id: number) => {
    const res = await api.post<ApiResponse<Contract>>(`/contracts/${id}/follow-up`);
    return res.data;
  },
  getPassword: async (id: number) => {
    const res = await api.get<ApiResponse<{ password: string }>>(`/contracts/${id}/password`);
    return res.data;
  },
  getSimCardCredentials: async (simCardId: number) => {
    const res = await api.get<ApiResponse<{ pin: string | null; puk: string | null }>>(`/contracts/simcard/${simCardId}/credentials`);
    return res.data;
  },
  getInternetCredentials: async (contractId: number) => {
    const res = await api.get<ApiResponse<{ password: string | null }>>(`/contracts/${contractId}/internet-credentials`);
    return res.data;
  },
  getSipCredentials: async (phoneNumberId: number) => {
    const res = await api.get<ApiResponse<{ password: string | null }>>(`/contracts/phonenumber/${phoneNumberId}/sip-credentials`);
    return res.data;
  },
  // Vertrags-Cockpit
  getCockpit: async () => {
    const res = await api.get<ApiResponse<import('../types').CockpitResult>>('/contracts/cockpit');
    return res.data;
  },
};

// Contract Tasks (Aufgaben)
export const contractTaskApi = {
  // Alle Tasks über alle Verträge (für Task-Liste & Dashboard)
  getAll: async (params?: { status?: ContractTaskStatus; customerId?: number }) => {
    const res = await api.get<ApiResponse<ContractTask[]>>('/tasks', { params });
    return res.data;
  },
  // Task-Statistik (offene Aufgaben)
  getStats: async () => {
    const res = await api.get<ApiResponse<{ openCount: number }>>('/tasks/stats');
    return res.data;
  },
  // Tasks für einen spezifischen Vertrag
  getByContract: async (contractId: number, status?: ContractTaskStatus) => {
    const res = await api.get<ApiResponse<ContractTask[]>>(`/contracts/${contractId}/tasks`, { params: { status } });
    return res.data;
  },
  create: async (contractId: number, data: { title: string; description?: string; visibleInPortal?: boolean }) => {
    const res = await api.post<ApiResponse<ContractTask>>(`/contracts/${contractId}/tasks`, data);
    return res.data;
  },
  update: async (taskId: number, data: { title?: string; description?: string; visibleInPortal?: boolean }) => {
    const res = await api.put<ApiResponse<ContractTask>>(`/tasks/${taskId}`, data);
    return res.data;
  },
  complete: async (taskId: number) => {
    const res = await api.post<ApiResponse<ContractTask>>(`/tasks/${taskId}/complete`);
    return res.data;
  },
  reopen: async (taskId: number) => {
    const res = await api.post<ApiResponse<ContractTask>>(`/tasks/${taskId}/reopen`);
    return res.data;
  },
  delete: async (taskId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/tasks/${taskId}`);
    return res.data;
  },
  // Subtasks
  createSubtask: async (taskId: number, title: string) => {
    const res = await api.post<ApiResponse<ContractTaskSubtask>>(`/tasks/${taskId}/subtasks`, { title });
    return res.data;
  },
  // Kundenportal: Antwort auf eigenes Ticket
  createReply: async (taskId: number, title: string) => {
    const res = await api.post<ApiResponse<ContractTaskSubtask>>(`/tasks/${taskId}/reply`, { title });
    return res.data;
  },
  updateSubtask: async (subtaskId: number, title: string) => {
    const res = await api.put<ApiResponse<ContractTaskSubtask>>(`/subtasks/${subtaskId}`, { title });
    return res.data;
  },
  completeSubtask: async (subtaskId: number) => {
    const res = await api.post<ApiResponse<ContractTaskSubtask>>(`/subtasks/${subtaskId}/complete`);
    return res.data;
  },
  reopenSubtask: async (subtaskId: number) => {
    const res = await api.post<ApiResponse<ContractTaskSubtask>>(`/subtasks/${subtaskId}/reopen`);
    return res.data;
  },
  deleteSubtask: async (subtaskId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/subtasks/${subtaskId}`);
    return res.data;
  },
  // Support-Ticket erstellen (für Kundenportal)
  createSupportTicket: async (contractId: number, data: { title: string; description?: string }) => {
    const res = await api.post<ApiResponse<ContractTask>>(`/contracts/${contractId}/support-ticket`, data);
    return res.data;
  },
};

// App Settings
export const appSettingsApi = {
  getPublic: async () => {
    const res = await api.get<ApiResponse<Record<string, string>>>('/settings/public');
    return res.data;
  },
  getAll: async () => {
    const res = await api.get<ApiResponse<Record<string, string>>>('/settings');
    return res.data;
  },
  update: async (settings: Record<string, string>) => {
    const res = await api.put<ApiResponse<void>>('/settings', settings);
    return res.data;
  },
  updateOne: async (key: string, value: string) => {
    const res = await api.put<ApiResponse<void>>(`/settings/${key}`, { value });
    return res.data;
  },
};

// Backup & Restore
export interface BackupInfo {
  name: string;
  timestamp: string;
  totalRecords: number;
  tables: { table: string; count: number }[];
  sizeBytes: number;
  hasUploads: boolean;
  uploadSizeBytes: number;
}

export const backupApi = {
  list: async () => {
    const res = await api.get<ApiResponse<BackupInfo[]>>('/settings/backups');
    return res.data;
  },
  create: async () => {
    const res = await api.post<ApiResponse<{ backupName: string }>>('/settings/backup');
    return res.data;
  },
  restore: async (name: string) => {
    const res = await api.post<ApiResponse<{ restoredRecords: number; restoredFiles: number }>>(`/settings/backup/${name}/restore`);
    return res.data;
  },
  delete: async (name: string) => {
    const res = await api.delete<ApiResponse<void>>(`/settings/backup/${name}`);
    return res.data;
  },
  getDownloadUrl: (name: string) => {
    return `/api/settings/backup/${name}/download`;
  },
  upload: async (file: File) => {
    const formData = new FormData();
    formData.append('backup', file);
    const res = await api.post<ApiResponse<{ backupName: string }>>('/settings/backup/upload', formData, {
      headers: { 'Content-Type': 'multipart/form-data' },
    });
    return res.data;
  },
  factoryReset: async () => {
    const res = await api.post<ApiResponse<void>>('/settings/factory-reset');
    return res.data;
  },
};

// Platforms
export const platformApi = {
  getAll: async (includeInactive = false) => {
    const res = await api.get<ApiResponse<SalesPlatform[]>>('/platforms', { params: { includeInactive } });
    return res.data;
  },
  getById: async (id: number) => {
    const res = await api.get<ApiResponse<SalesPlatform>>(`/platforms/${id}`);
    return res.data;
  },
  create: async (data: Partial<SalesPlatform>) => {
    const res = await api.post<ApiResponse<SalesPlatform>>('/platforms', data);
    return res.data;
  },
  update: async (id: number, data: Partial<SalesPlatform>) => {
    const res = await api.put<ApiResponse<SalesPlatform>>(`/platforms/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/platforms/${id}`);
    return res.data;
  },
};

// Cancellation Periods
export const cancellationPeriodApi = {
  getAll: async (includeInactive = false) => {
    const res = await api.get<ApiResponse<CancellationPeriod[]>>('/cancellation-periods', { params: { includeInactive } });
    return res.data;
  },
  getById: async (id: number) => {
    const res = await api.get<ApiResponse<CancellationPeriod>>(`/cancellation-periods/${id}`);
    return res.data;
  },
  create: async (data: Partial<CancellationPeriod>) => {
    const res = await api.post<ApiResponse<CancellationPeriod>>('/cancellation-periods', data);
    return res.data;
  },
  update: async (id: number, data: Partial<CancellationPeriod>) => {
    const res = await api.put<ApiResponse<CancellationPeriod>>(`/cancellation-periods/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/cancellation-periods/${id}`);
    return res.data;
  },
};

// Contract Durations
export const contractDurationApi = {
  getAll: async (includeInactive = false) => {
    const res = await api.get<ApiResponse<ContractDuration[]>>('/contract-durations', { params: { includeInactive } });
    return res.data;
  },
  getById: async (id: number) => {
    const res = await api.get<ApiResponse<ContractDuration>>(`/contract-durations/${id}`);
    return res.data;
  },
  create: async (data: Partial<ContractDuration>) => {
    const res = await api.post<ApiResponse<ContractDuration>>('/contract-durations', data);
    return res.data;
  },
  update: async (id: number, data: Partial<ContractDuration>) => {
    const res = await api.put<ApiResponse<ContractDuration>>(`/contract-durations/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/contract-durations/${id}`);
    return res.data;
  },
};

// Contract Categories (Vertragstypen)
export const contractCategoryApi = {
  getAll: async (includeInactive = false) => {
    const res = await api.get<ApiResponse<ContractCategory[]>>('/contract-categories', { params: { includeInactive } });
    return res.data;
  },
  getById: async (id: number) => {
    const res = await api.get<ApiResponse<ContractCategory>>(`/contract-categories/${id}`);
    return res.data;
  },
  create: async (data: Partial<ContractCategory>) => {
    const res = await api.post<ApiResponse<ContractCategory>>('/contract-categories', data);
    return res.data;
  },
  update: async (id: number, data: Partial<ContractCategory>) => {
    const res = await api.put<ApiResponse<ContractCategory>>(`/contract-categories/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/contract-categories/${id}`);
    return res.data;
  },
};

// Providers (Anbieter)
export const providerApi = {
  getAll: async (includeInactive = false) => {
    const res = await api.get<ApiResponse<Provider[]>>('/providers', { params: { includeInactive } });
    return res.data;
  },
  getById: async (id: number) => {
    const res = await api.get<ApiResponse<Provider>>(`/providers/${id}`);
    return res.data;
  },
  create: async (data: Partial<Provider>) => {
    const res = await api.post<ApiResponse<Provider>>('/providers', data);
    return res.data;
  },
  update: async (id: number, data: Partial<Provider>) => {
    const res = await api.put<ApiResponse<Provider>>(`/providers/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/providers/${id}`);
    return res.data;
  },
  getTariffs: async (providerId: number, includeInactive = false) => {
    const res = await api.get<ApiResponse<Tariff[]>>(`/providers/${providerId}/tariffs`, { params: { includeInactive } });
    return res.data;
  },
  createTariff: async (providerId: number, data: Partial<Tariff>) => {
    const res = await api.post<ApiResponse<Tariff>>(`/providers/${providerId}/tariffs`, data);
    return res.data;
  },
};

// Tariffs (Tarife)
export const tariffApi = {
  getById: async (id: number) => {
    const res = await api.get<ApiResponse<Tariff>>(`/tariffs/${id}`);
    return res.data;
  },
  update: async (id: number, data: Partial<Tariff>) => {
    const res = await api.put<ApiResponse<Tariff>>(`/tariffs/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/tariffs/${id}`);
    return res.data;
  },
};

// Upload
export const uploadApi = {
  uploadBankCardDocument: async (bankCardId: number, file: File) => {
    const formData = new FormData();
    formData.append('document', file);
    const res = await api.post<ApiResponse<{ path: string; filename: string }>>(`/upload/bank-cards/${bankCardId}`, formData, {
      headers: { 'Content-Type': 'multipart/form-data' },
    });
    return res.data;
  },
  uploadIdentityDocument: async (documentId: number, file: File) => {
    const formData = new FormData();
    formData.append('document', file);
    const res = await api.post<ApiResponse<{ path: string; filename: string }>>(`/upload/documents/${documentId}`, formData, {
      headers: { 'Content-Type': 'multipart/form-data' },
    });
    return res.data;
  },
  deleteBankCardDocument: async (bankCardId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/upload/bank-cards/${bankCardId}`);
    return res.data;
  },
  deleteIdentityDocument: async (documentId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/upload/documents/${documentId}`);
    return res.data;
  },
  uploadBusinessRegistration: async (customerId: number, file: File) => {
    const formData = new FormData();
    formData.append('document', file);
    const res = await api.post<ApiResponse<{ path: string; filename: string }>>(`/upload/customers/${customerId}/business-registration`, formData, {
      headers: { 'Content-Type': 'multipart/form-data' },
    });
    return res.data;
  },
  deleteBusinessRegistration: async (customerId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/upload/customers/${customerId}/business-registration`);
    return res.data;
  },
  uploadCommercialRegister: async (customerId: number, file: File) => {
    const formData = new FormData();
    formData.append('document', file);
    const res = await api.post<ApiResponse<{ path: string; filename: string }>>(`/upload/customers/${customerId}/commercial-register`, formData, {
      headers: { 'Content-Type': 'multipart/form-data' },
    });
    return res.data;
  },
  deleteCommercialRegister: async (customerId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/upload/customers/${customerId}/commercial-register`);
    return res.data;
  },
  uploadPrivacyPolicy: async (customerId: number, file: File) => {
    const formData = new FormData();
    formData.append('document', file);
    const res = await api.post<ApiResponse<{ path: string; filename: string }>>(`/upload/customers/${customerId}/privacy-policy`, formData, {
      headers: { 'Content-Type': 'multipart/form-data' },
    });
    return res.data;
  },
  deletePrivacyPolicy: async (customerId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/upload/customers/${customerId}/privacy-policy`);
    return res.data;
  },
  // Contract Documents
  uploadCancellationLetter: async (contractId: number, file: File) => {
    const formData = new FormData();
    formData.append('document', file);
    const res = await api.post<ApiResponse<{ path: string; filename: string }>>(`/upload/contracts/${contractId}/cancellation-letter`, formData, {
      headers: { 'Content-Type': 'multipart/form-data' },
    });
    return res.data;
  },
  deleteCancellationLetter: async (contractId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/upload/contracts/${contractId}/cancellation-letter`);
    return res.data;
  },
  uploadCancellationConfirmation: async (contractId: number, file: File) => {
    const formData = new FormData();
    formData.append('document', file);
    const res = await api.post<ApiResponse<{ path: string; filename: string }>>(`/upload/contracts/${contractId}/cancellation-confirmation`, formData, {
      headers: { 'Content-Type': 'multipart/form-data' },
    });
    return res.data;
  },
  deleteCancellationConfirmation: async (contractId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/upload/contracts/${contractId}/cancellation-confirmation`);
    return res.data;
  },
  uploadCancellationLetterOptions: async (contractId: number, file: File) => {
    const formData = new FormData();
    formData.append('document', file);
    const res = await api.post<ApiResponse<{ path: string; filename: string }>>(`/upload/contracts/${contractId}/cancellation-letter-options`, formData, {
      headers: { 'Content-Type': 'multipart/form-data' },
    });
    return res.data;
  },
  deleteCancellationLetterOptions: async (contractId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/upload/contracts/${contractId}/cancellation-letter-options`);
    return res.data;
  },
  uploadCancellationConfirmationOptions: async (contractId: number, file: File) => {
    const formData = new FormData();
    formData.append('document', file);
    const res = await api.post<ApiResponse<{ path: string; filename: string }>>(`/upload/contracts/${contractId}/cancellation-confirmation-options`, formData, {
      headers: { 'Content-Type': 'multipart/form-data' },
    });
    return res.data;
  },
  deleteCancellationConfirmationOptions: async (contractId: number) => {
    const res = await api.delete<ApiResponse<void>>(`/upload/contracts/${contractId}/cancellation-confirmation-options`);
    return res.data;
  },
};

// Users
export const userApi = {
  getAll: async (params?: { search?: string; isActive?: boolean; roleId?: number; page?: number; limit?: number }) => {
    const res = await api.get<ApiResponse<User[]>>('/users', { params });
    return res.data;
  },
  getById: async (id: number) => {
    const res = await api.get<ApiResponse<User>>(`/users/${id}`);
    return res.data;
  },
  create: async (data: { email: string; password: string; firstName: string; lastName: string; roleIds: number[]; customerId?: number; hasDeveloperAccess?: boolean }) => {
    const res = await api.post<ApiResponse<User>>('/users', data);
    return res.data;
  },
  update: async (id: number, data: Partial<User> & { password?: string; roleIds?: number[] }) => {
    const res = await api.put<ApiResponse<User>>(`/users/${id}`, data);
    return res.data;
  },
  delete: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/users/${id}`);
    return res.data;
  },
  getRoles: async () => {
    const res = await api.get<ApiResponse<Role[]>>('/users/roles/list');
    return res.data;
  },
};

// Developer
export const developerApi = {
  getSchema: async () => {
    const res = await api.get<ApiResponse<any[]>>('/developer/schema');
    return res.data;
  },
  getTableData: async (tableName: string, page = 1, limit = 50) => {
    const res = await api.get<ApiResponse<any[]>>(`/developer/table/${tableName}`, { params: { page, limit } });
    return res.data;
  },
  updateRow: async (tableName: string, id: string, data: Record<string, any>) => {
    const res = await api.put<ApiResponse<any>>(`/developer/table/${tableName}/${id}`, data);
    return res.data;
  },
  deleteRow: async (tableName: string, id: string) => {
    const res = await api.delete<ApiResponse<void>>(`/developer/table/${tableName}/${id}`);
    return res.data;
  },
  getReference: async (tableName: string) => {
    const res = await api.get<ApiResponse<any[]>>(`/developer/reference/${tableName}`);
    return res.data;
  },
};

// Email Provider (für Stressfrei-Wechseln Provisionierung)
export interface EmailProviderConfig {
  id: number;
  name: string;
  type: 'PLESK' | 'CPANEL' | 'DIRECTADMIN';
  apiUrl: string;
  apiKey?: string;
  username?: string;
  passwordEncrypted?: string;
  domain: string;
  defaultForwardEmail?: string;
  // IMAP/SMTP-Server (für E-Mail-Client)
  imapServer?: string;
  imapPort?: number;
  smtpServer?: string;
  smtpPort?: number;
  // Verschlüsselungs-Einstellungen
  imapEncryption?: 'SSL' | 'STARTTLS' | 'NONE';
  smtpEncryption?: 'SSL' | 'STARTTLS' | 'NONE';
  allowSelfSignedCerts?: boolean; // Selbstsignierte Zertifikate erlauben
  isActive: boolean;
  isDefault: boolean;
  createdAt: string;
  updatedAt: string;
}

export interface EmailOperationResult {
  success: boolean;
  message?: string;
  error?: string;
}

export const emailProviderApi = {
  // Config CRUD
  getConfigs: async () => {
    const res = await api.get<ApiResponse<EmailProviderConfig[]>>('/email-providers/configs');
    return res.data;
  },
  getConfig: async (id: number) => {
    const res = await api.get<ApiResponse<EmailProviderConfig>>(`/email-providers/configs/${id}`);
    return res.data;
  },
  createConfig: async (data: Partial<EmailProviderConfig> & { password?: string }) => {
    const res = await api.post<ApiResponse<EmailProviderConfig>>('/email-providers/configs', data);
    return res.data;
  },
  updateConfig: async (id: number, data: Partial<EmailProviderConfig> & { password?: string }) => {
    const res = await api.put<ApiResponse<EmailProviderConfig>>(`/email-providers/configs/${id}`, data);
    return res.data;
  },
  deleteConfig: async (id: number) => {
    const res = await api.delete<ApiResponse<void>>(`/email-providers/configs/${id}`);
    return res.data;
  },
  // Email Operations
  testConnection: async (options?: {
    id?: number;
    testData?: {
      type: 'PLESK' | 'CPANEL' | 'DIRECTADMIN';
      apiUrl: string;
      apiKey?: string;
      username?: string;
      password?: string;
      domain: string;
    };
  }) => {
    const body = options?.testData
      ? { ...options.testData }
      : options?.id
        ? { id: options.id }
        : {};
    const res = await api.post<ApiResponse<EmailOperationResult>>('/email-providers/test-connection', body);
    return res.data;
  },
  getDomain: async () => {
    const res = await api.get<ApiResponse<{ domain: string | null }>>('/email-providers/domain');
    return res.data;
  },
  checkEmailExists: async (localPart: string) => {
    const res = await api.get<ApiResponse<{ exists: boolean; email?: string }>>(`/email-providers/check/${localPart}`);
    return res.data;
  },
  provisionEmail: async (localPart: string, customerEmail: string) => {
    const res = await api.post<ApiResponse<EmailOperationResult>>('/email-providers/provision', { localPart, customerEmail });
    return res.data;
  },
  deprovisionEmail: async (localPart: string) => {
    const res = await api.delete<ApiResponse<EmailOperationResult>>(`/email-providers/deprovision/${localPart}`);
    return res.data;
  },
};

export default api;