(fix) Prevent feed offset from exceeding the maximum offset of the filtered...

(fix) Prevent feed offset from exceeding the maximum offset of the filtered feed; Minor extract refactor to explain by method name - #2190

src/app/common/components/featured-content/featured-content.service.ts

@@ -5,6 +5,7 @@ import { FeedsService } from '../../services/feeds.service';
 @Injectable()
 export class FeaturedContentService {
   offset: number = -1;
+  maximumOffset: number = 0;
 
   constructor(protected feedsService: FeedsService) {
     this.feedsService
@@ -12,20 +13,25 @@ export class FeaturedContentService {
       .setOffset(0)
       .setEndpoint('api/v2/boost/feed')
       .fetch();
+
+    this.feedsService.feed.subscribe(feed => {
+      this.maximumOffset = feed.length - 1;
+    });
   }
 
   async fetch() {
-    if (this.offset++ >= this.feedsService.rawFeed.getValue().length - 1) {
+    if (this.offset++ >= this.maximumOffset) {
       this.offset = 0;
+      this.fetchNextFeed();
     }
-    // Refetch every 2 calls, if not loading
-    if (this.offset % 2 && !this.feedsService.inProgress.getValue()) {
-      this.feedsService.clear();
-      this.feedsService.fetch();
-    }
+
+    return this.entityFromFeed();
+  }
+
+  protected async entityFromFeed() {
     return await this.feedsService.feed
       .pipe(
-        filter(feed => feed.length > 0),
+        filter(item => item.length > 0),
         first(),
         mergeMap(feed => feed),
         skip(this.offset),
@@ -39,4 +45,11 @@ export class FeaturedContentService {
       )
       .toPromise();
   }
+
+  protected fetchNextFeed() {
+    if (!this.feedsService.inProgress.getValue()) {
+      this.feedsService.clear();
+      this.feedsService.fetch();
+    }
+  }
 }