Extract NotificationList state (#2185)

* Extract NotificationList state

js/src/forum/states/NotificationListState.js

@@ -0,0 +1,94 @@
+export default class NotificationListState {
+  constructor(app) {
+    this.app = app;
+
+    this.notificationPages = [];
+
+    this.loading = false;
+
+    this.moreResults = false;
+  }
+
+  getNotificationPages() {
+    return this.notificationPages;
+  }
+
+  isLoading() {
+    return this.loading;
+  }
+
+  hasMoreResults() {
+    return this.moreResults;
+  }
+
+  /**
+   * Load notifications into the application's cache if they haven't already
+   * been loaded.
+   */
+  load() {
+    if (this.app.session.user.newNotificationCount()) {
+      this.notificationPages = [];
+    }
+
+    if (this.notificationPages.length > 0) {
+      return;
+    }
+
+    this.app.session.user.pushAttributes({ newNotificationCount: 0 });
+
+    this.loadMore();
+  }
+
+  /**
+   * Load the next page of notification results.
+   *
+   * @public
+   */
+  loadMore() {
+    this.loading = true;
+    m.redraw();
+
+    const params = this.notificationPages.length > 0 ? { page: { offset: this.notificationPages.length * 10 } } : null;
+
+    return this.app.store
+      .find('notifications', params)
+      .then(this.parseResults.bind(this))
+      .catch(() => {})
+      .then(() => {
+        this.loading = false;
+        m.redraw();
+      });
+  }
+
+  /**
+   * Parse results and append them to the notification list.
+   *
+   * @param {Notification[]} results
+   * @return {Notification[]}
+   */
+  parseResults(results) {
+    if (results.length) this.notificationPages.push(results);
+
+    this.moreResults = !!results.payload.links.next;
+
+    return results;
+  }
+
+  /**
+   * Mark all of the notifications as read.
+   */
+  markAllAsRead() {
+    if (this.notificationPages.length === 0) return;
+
+    this.app.session.user.pushAttributes({ unreadNotificationCount: 0 });
+
+    this.notificationPages.forEach((notifications) => {
+      notifications.forEach((notification) => notification.pushAttributes({ isRead: true }));
+    });
+
+    this.app.request({
+      url: this.app.forum.attribute('apiUrl') + '/notifications/read',
+      method: 'POST',
+    });
+  }
+}