import { from, of } from 'rxjs';
import { catchError, concatMap, filter, last, switchMap } from 'rxjs/operators';

import { actions } from '../actions';

import type { Flow } from '@equinor/fusion-observable';
import type { AppModuleProvider } from '../../AppModuleProvider';
import type { Actions } from '../actions';
import type { AppBundleState } from '../types';

/**
 * Handles the set settings action by setting the app settings from the provider,
 * filtering out null values, and dispatching success or failure actions accordingly.
 *
 * @param provider The AppModuleProvider used to fetch the app settings.
 * @returns A Flow function that takes an Observable of actions and returns an Observable of actions.
 */
export const handleUpdateSettings =
  (provider: AppModuleProvider): Flow<Actions, AppBundleState> =>
  (action$) => {
    // only handle update settings request actions
    return action$.pipe(
      filter(actions.updateSettings.match),
      switchMap(({ payload }) => {
        const { appKey, settings } = payload;
        // take the last value, then request updating of settings and dispatch success or failure
        return provider.updateAppSettings(appKey, settings).pipe(
          last(),
          concatMap((updatedSettings) =>
            from([
              actions.setSettings(updatedSettings),
              actions.updateSettings.success(updatedSettings),
            ]),
          ),
          catchError((err) => of(actions.updateSettings.failure(err))),
        );
      }),
    );
  };