[CST-5246] Correction service should support multiple providers

src/app/notifications/notifications-state.service.ts

@@ -0,0 +1,116 @@
+import { Injectable } from '@angular/core';
+import { select, Store } from '@ngrx/store';
+import { Observable } from 'rxjs';
+import { map } from 'rxjs/operators';
+import {
+  getNotificationsBrokerTopicsCurrentPageSelector,
+  getNotificationsBrokerTopicsTotalPagesSelector,
+  getNotificationsBrokerTopicsTotalsSelector,
+  isNotificationsBrokerTopicsLoadedSelector,
+  notificationsBrokerTopicsObjectSelector,
+  isNotificationsBrokerTopicsProcessingSelector
+} from './selectors';
+import { NotificationsBrokerTopicObject } from '../core/notifications/broker/models/notifications-broker-topic.model';
+import { NotificationsState } from './notifications.reducer';
+import { RetrieveAllTopicsAction } from './broker/topics/notifications-broker-topics.actions';
+
+/**
+ * The service handling the Notifications State.
+ */
+@Injectable()
+export class NotificationsStateService {
+
+  /**
+   * Initialize the service variables.
+   * @param {Store<NotificationsState>} store
+   */
+  constructor(private store: Store<NotificationsState>) { }
+
+  // Notifications Broker topics
+  // --------------------------------------------------------------------------
+
+  /**
+   * Returns the list of Notifications Broker topics from the state.
+   *
+   * @return Observable<NotificationsBrokerTopicObject>
+   *    The list of Notifications Broker topics.
+   */
+  public getNotificationsBrokerTopics(): Observable<NotificationsBrokerTopicObject[]> {
+    return this.store.pipe(select(notificationsBrokerTopicsObjectSelector()));
+  }
+
+  /**
+   * Returns the information about the loading status of the Notifications Broker topics (if it's running or not).
+   *
+   * @return Observable<boolean>
+   *    'true' if the topics are loading, 'false' otherwise.
+   */
+  public isNotificationsBrokerTopicsLoading(): Observable<boolean> {
+    return this.store.pipe(
+      select(isNotificationsBrokerTopicsLoadedSelector),
+      map((loaded: boolean) => !loaded)
+    );
+  }
+
+  /**
+   * Returns the information about the loading status of the Notifications Broker topics (whether or not they were loaded).
+   *
+   * @return Observable<boolean>
+   *    'true' if the topics are loaded, 'false' otherwise.
+   */
+  public isNotificationsBrokerTopicsLoaded(): Observable<boolean> {
+    return this.store.pipe(select(isNotificationsBrokerTopicsLoadedSelector));
+  }
+
+  /**
+   * Returns the information about the processing status of the Notifications Broker topics (if it's running or not).
+   *
+   * @return Observable<boolean>
+   *    'true' if there are operations running on the topics (ex.: a REST call), 'false' otherwise.
+   */
+  public isNotificationsBrokerTopicsProcessing(): Observable<boolean> {
+    return this.store.pipe(select(isNotificationsBrokerTopicsProcessingSelector));
+  }
+
+  /**
+   * Returns, from the state, the total available pages of the Notifications Broker topics.
+   *
+   * @return Observable<number>
+   *    The number of the Notifications Broker topics pages.
+   */
+  public getNotificationsBrokerTopicsTotalPages(): Observable<number> {
+    return this.store.pipe(select(getNotificationsBrokerTopicsTotalPagesSelector));
+  }
+
+  /**
+   * Returns the current page of the Notifications Broker topics, from the state.
+   *
+   * @return Observable<number>
+   *    The number of the current Notifications Broker topics page.
+   */
+  public getNotificationsBrokerTopicsCurrentPage(): Observable<number> {
+    return this.store.pipe(select(getNotificationsBrokerTopicsCurrentPageSelector));
+  }
+
+  /**
+   * Returns the total number of the Notifications Broker topics.
+   *
+   * @return Observable<number>
+   *    The number of the Notifications Broker topics.
+   */
+  public getNotificationsBrokerTopicsTotals(): Observable<number> {
+    return this.store.pipe(select(getNotificationsBrokerTopicsTotalsSelector));
+  }
+
+  /**
+   * Dispatch a request to change the Notifications Broker topics state, retrieving the topics from the server.
+   *
+   * @param elementsPerPage
+   *    The number of the topics per page.
+   * @param currentPage
+   *    The number of the current page.
+   */
+  public dispatchRetrieveNotificationsBrokerTopics(elementsPerPage: number, currentPage: number): void {
+    this.store.dispatch(new RetrieveAllTopicsAction(elementsPerPage, currentPage));
+  }
+}