/**
 * Proxmox Module API client (260923-dhh). Konsumiert `/modules/proxmox/*`.
 * Vorbild `dkv-api.ts`: `credentials: 'include'` fuer Cookie-Auth,
 * `NEXT_PUBLIC_API_URL` als Basis.
 *
 * Sicherheit (T-DHH-01): keine Antwort dieses Clients enthaelt jemals ein
 * Geheimnisfeld — der Server waehlt `encryptedTokenSecret`/`encryptedPassword`
 * per `select` gar nicht erst aus.
 */

const API_URL = process.env.NEXT_PUBLIC_API_URL || 'http://localhost:3001';

export type ProxmoxProductType = 'pve' | 'pbs' | 'pmg';
export type ProxmoxAuthMethod = 'token' | 'password';
export type ProxmoxErrorKind =
  | 'netz'
  | 'zugang'
  | 'rechte'
  | 'zertifikat'
  | 'antwortform'
  | 'server'
  | 'unbekannt';

export interface ProxmoxPveNodeMetric {
  node: string;
  cpu: number | null;
  maxcpu: number | null;
  mem: number | null;
  maxmem: number | null;
}

export interface ProxmoxPveStorageMetric {
  storage: string;
  node: string;
  disk: number | null;
  maxdisk: number | null;
}

/** Gast, der nicht laeuft, obwohl Autostart aktiv ist (quick-261005). */
export interface ProxmoxPveAutostartGuest {
  vmid: number;
  name: string | null;
  type: 'qemu' | 'lxc';
  node: string;
  status: string;
}

export interface ProxmoxPveMetrics {
  productType: 'pve';
  nodeCount: number;
  guestsRunning: number;
  guestsStopped: number;
  nodes: ProxmoxPveNodeMetric[];
  storages: ProxmoxPveStorageMetric[];
  /** Fehlt in Zwischenlagerstaenden von vor quick-261005. */
  autostartStopped?: ProxmoxPveAutostartGuest[];
  /** Gestoppte Gaeste, deren Autostart nicht gelesen werden konnte. */
  autostartUnchecked?: number;
}

export interface ProxmoxPbsDatastoreMetric {
  name: string;
  total: number | null;
  used: number | null;
  free: number | null;
  lastBackupAt: number | null;
  lastVerifyState: string | null;
}

export interface ProxmoxPbsMetrics {
  productType: 'pbs';
  datastores: ProxmoxPbsDatastoreMetric[];
}

export interface ProxmoxPmgMetrics {
  productType: 'pmg';
  countIn: number | null;
  countOut: number | null;
  spamCount: number | null;
  virusCount: number | null;
}

export type ProxmoxMetrics = ProxmoxPveMetrics | ProxmoxPbsMetrics | ProxmoxPmgMetrics;

export interface ProxmoxServerStatus {
  id: string;
  serverId: string;
  lastPolledAt: string | null;
  lastOkAt: string | null;
  reachable: boolean;
  errorKind: ProxmoxErrorKind | null;
  errorDetail: string | null;
  metrics: ProxmoxMetrics | null;
  rawSample: unknown;
  updatedAt: string;
}

export interface ProxmoxServer {
  id: string;
  tenantId: string;
  name: string;
  productType: ProxmoxProductType;
  baseUrl: string;
  authMethod: ProxmoxAuthMethod;
  tokenId: string | null;
  username: string | null;
  tlsRejectUnauthorized: boolean;
  isActive: boolean;
  pollIntervalMin: number;
  position: number;
  createdAt: string;
  updatedAt: string;
  status: ProxmoxServerStatus | null;
}

export interface CreateProxmoxServerPayload {
  name: string;
  productType: ProxmoxProductType;
  baseUrl: string;
  authMethod: ProxmoxAuthMethod;
  tokenId?: string;
  tokenSecret?: string;
  username?: string;
  password?: string;
  tlsRejectUnauthorized?: boolean;
  pollIntervalMin?: number;
  isActive?: boolean;
}

export type UpdateProxmoxServerPayload = Partial<CreateProxmoxServerPayload>;

export interface ProxmoxTestResult {
  reachable: boolean;
  errorKind: ProxmoxErrorKind | null;
  errorDetail: string | null;
  metrics: ProxmoxMetrics | null;
  rawSample: unknown;
}

/** Liest die NestJS-Fehlermeldung aus dem Antwortkoerper, faellt sonst auf einen Standardtext zurueck. */
async function readErrorMessage(res: Response, fallback: string): Promise<string> {
  try {
    const body = await res.json();
    if (typeof body?.message === 'string') return body.message;
    if (Array.isArray(body?.message) && body.message.length > 0) return String(body.message[0]);
  } catch {
    /* Antwort war kein JSON — Standardtext bleibt */
  }
  return fallback;
}

/** GET /modules/proxmox/servers — Serverliste samt Zwischenlager. */
export async function listServers(): Promise<ProxmoxServer[]> {
  const res = await fetch(`${API_URL}/modules/proxmox/servers`, {
    credentials: 'include',
  });
  if (!res.ok) throw new Error('Failed to fetch proxmox servers');
  return res.json();
}

/** POST /modules/proxmox/servers — Server anlegen (ADMIN/SUPER_ADMIN). */
export async function createServer(
  payload: CreateProxmoxServerPayload,
): Promise<ProxmoxServer> {
  const res = await fetch(`${API_URL}/modules/proxmox/servers`, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    credentials: 'include',
    body: JSON.stringify(payload),
  });
  if (!res.ok) throw new Error(await readErrorMessage(res, 'Failed to create proxmox server'));
  return res.json();
}

/** PUT /modules/proxmox/servers/:id — Server bearbeiten (ADMIN/SUPER_ADMIN). */
export async function updateServer(
  id: string,
  payload: UpdateProxmoxServerPayload,
): Promise<ProxmoxServer> {
  const res = await fetch(`${API_URL}/modules/proxmox/servers/${id}`, {
    method: 'PUT',
    headers: { 'Content-Type': 'application/json' },
    credentials: 'include',
    body: JSON.stringify(payload),
  });
  if (!res.ok) throw new Error(await readErrorMessage(res, 'Failed to update proxmox server'));
  return res.json();
}

/** DELETE /modules/proxmox/servers/:id — Server samt Zwischenlagerzeile loeschen (ADMIN/SUPER_ADMIN). */
export async function deleteServer(id: string): Promise<void> {
  const res = await fetch(`${API_URL}/modules/proxmox/servers/${id}`, {
    method: 'DELETE',
    credentials: 'include',
  });
  if (!res.ok) throw new Error(await readErrorMessage(res, 'Failed to delete proxmox server'));
}

/** POST /modules/proxmox/servers/:id/poll — sofortige Abfrage (ADMIN/SUPER_ADMIN). */
export async function pollServer(id: string): Promise<ProxmoxTestResult> {
  const res = await fetch(`${API_URL}/modules/proxmox/servers/${id}/poll`, {
    method: 'POST',
    credentials: 'include',
  });
  if (!res.ok) throw new Error(await readErrorMessage(res, 'Failed to poll proxmox server'));
  return res.json();
}

/**
 * POST /modules/proxmox/servers/:id/test — Verbindungstest fuer einen
 * gespeicherten Server, schreibt NICHT ins Zwischenlager. `payload` traegt
 * den aktuellen Formularstand (Nachbesserung Befund 1): der Test prueft
 * damit, was im Formular steht, statt blind den gespeicherten Stand — ein
 * leer gelassenes Geheimnisfeld (`tokenSecret`/`password: undefined`) laesst
 * den Server serverseitig auf den gespeicherten Wert zurueckfallen.
 */
export async function testServer(
  id: string,
  payload: UpdateProxmoxServerPayload,
): Promise<ProxmoxTestResult> {
  const res = await fetch(`${API_URL}/modules/proxmox/servers/${id}/test`, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    credentials: 'include',
    body: JSON.stringify(payload),
  });
  if (!res.ok) throw new Error(await readErrorMessage(res, 'Failed to test proxmox server'));
  return res.json();
}

/**
 * POST /modules/proxmox/servers/test — Verbindungstest waehrend der
 * Neuanlage (Nachbesserung Befund 1): es gibt noch keinen gespeicherten
 * Server, `payload` ist deshalb die einzige Quelle.
 */
export async function testDraftServer(
  payload: UpdateProxmoxServerPayload,
): Promise<ProxmoxTestResult> {
  const res = await fetch(`${API_URL}/modules/proxmox/servers/test`, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    credentials: 'include',
    body: JSON.stringify(payload),
  });
  if (!res.ok) throw new Error(await readErrorMessage(res, 'Failed to test proxmox server'));
  return res.json();
}