import type { ServiceWorkerEventHost } from "./service-worker-runtime.ts";

type NotificationOptions = Parameters<
  ServiceWorkerEventHost["registration"]["showNotification"]
>[1];
type MatchAllOptions = Parameters<
  ServiceWorkerEventHost["clients"]["matchAll"]
>[0];

/**
 * Adapts a native Service Worker global scope onto the structural
 * {@link ServiceWorkerEventHost} facade.
 *
 * The native `showNotification` call lives here because `src/adapters/web-push`
 * is the owner of the notification API. The single physical worker entry
 * (§17.1) composes the runtime but never touches the native API itself.
 */

export type NativeWorkerScope = Readonly<{
  location: Readonly<{ origin: string }>;
  registration: Readonly<{
    showNotification(title: string, options: unknown): Promise<void>;
  }>;
  clients: Readonly<{
    matchAll(options: unknown): Promise<readonly unknown[]>;
    openWindow(url: string): Promise<unknown>;
  }>;
  // Deliberately loose: a native scope declares a richly overloaded listener
  // signature, and this facade only needs to forward the registration.
  addEventListener(type: string, listener: never, options?: never): void;
  removeEventListener(type: string, listener: never, options?: never): void;
}>;

export function createServiceWorkerScopeHost(
  scope: NativeWorkerScope,
): ServiceWorkerEventHost {
  return Object.freeze({
    origin: scope.location.origin,
    registration: Object.freeze({
      showNotification: (title: string, options: NotificationOptions) =>
        scope.registration.showNotification(title, {
          body: options.body,
          data: options.data,
          requireInteraction: options.requireInteraction,
          tag: options.tag,
        }),
    }),
    clients: Object.freeze({
      matchAll: (options: MatchAllOptions) => scope.clients.matchAll(options),
      openWindow: (url: string) => scope.clients.openWindow(url),
    }),
    addEventListener: (type, listener) =>
      scope.addEventListener(type, listener as never),
    removeEventListener: (type, listener) =>
      scope.removeEventListener(type, listener as never),
  });
}