// Detects whether the app is running inside the VNCmail+ (Bulwark) Electron
// desktop shell and wraps the native notification bridge that
// electron/preload.ts exposes via contextBridge. Mirrors how lib/web-push.ts
// mirrors the React Native push flow - same idea, different native API:
// PushManager/service-worker there, Electron's own Notification API here.
//
// Web/PWA deployments never get `window.vnc` at all (contextBridge only
// exists inside the Electron shell), so `isElectronShell()` is false there
// and callers should keep using the lib/web-push.ts + public/sw.js path.

export interface ShowNotificationOptions {
  body?: string;
  tag?: string;
}

export interface ShowNotificationResult {
  shown: boolean;
}

export interface WsMessageEvent {
  id: string;
  type: "open" | "message" | "close" | "error";
  data?: string;
  code?: number;
  message?: string;
}

export interface VncElectronBridge {
  isElectron: true;
  showNotification: (
    title: string,
    options?: ShowNotificationOptions,
  ) => Promise<ShowNotificationResult>;
  wsConnect: (url: string, authHeader: string) => Promise<string>;
  wsSend: (id: string, data: string) => Promise<boolean>;
  wsClose: (id: string) => Promise<void>;
  onWsMessage: (callback: (event: WsMessageEvent) => void) => () => void;
}

declare global {
  interface Window {
    vnc?: VncElectronBridge;
  }
}

export function isElectronShell(): boolean {
  return typeof window !== "undefined" && window.vnc?.isElectron === true;
}

/**
 * Shows a notification via Electron's native Notification API when running
 * inside the desktop shell. Resolves to false (never throws) when not
 * running in Electron, or when the main process reports notifications
 * unsupported on this OS/session - callers can fall back to the
 * service-worker push path (lib/web-push.ts) in that case.
 */
export async function showElectronNotification(
  title: string,
  options?: ShowNotificationOptions,
): Promise<boolean> {
  if (!isElectronShell()) return false;
  const result = await window.vnc!.showNotification(title, options);
  return result.shown;
}