import { Injectable } from "@angular/core";
import { EMPTY, concatMap } from "rxjs";

import { ApiService } from "@bitwarden/common/abstractions/api.service";
import {
  StateProvider,
  UNASSIGNED_ITEMS_BANNER_DISK,
  UserKeyDefinition,
} from "@bitwarden/common/platform/state";

export const SHOW_BANNER_KEY = new UserKeyDefinition<boolean>(
  UNASSIGNED_ITEMS_BANNER_DISK,
  "showBanner",
  {
    deserializer: (b) => b,
    clearOn: [],
  },
);

/** Displays a banner that tells users how to move their unassigned items into a collection. */
@Injectable({ providedIn: "root" })
export class UnassignedItemsBannerService {
  private _showBanner = this.stateProvider.getActive(SHOW_BANNER_KEY);

  showBanner$ = this._showBanner.state$.pipe(
    concatMap(async (showBanner) => {
      // null indicates that the user has not seen or dismissed the banner yet - get the flag from server
      if (showBanner == null) {
        const showBannerResponse = await this.apiService.getShowUnassignedCiphersBanner();
        await this._showBanner.update(() => showBannerResponse);
        return EMPTY; // complete the inner observable without emitting any value; the update on the previous line will trigger another run
      }

      return showBanner;
    }),
  );

  constructor(
    private stateProvider: StateProvider,
    private apiService: ApiService,
  ) {}

  async hideBanner() {
    await this._showBanner.update(() => false);
  }
}