client/src/app/videos/recommendations/recommended-videos.store.ts

   1 import { Inject, Injectable } from '@angular/core'
   2 import { Observable, ReplaySubject } from 'rxjs'
   3 import { Video } from '@app/shared/video/video.model'
   4 import { RecommendationInfo } from '@app/shared/video/recommendation-info.model'
   5 import { RecentVideosRecommendationService } from '@app/videos/recommendations/recent-videos-recommendation.service'
   6 import { RecommendationService, UUID } from '@app/videos/recommendations/recommendations.service'
   7 import { map, switchMap, take } from 'rxjs/operators'
   8
   9 /**
  10  * This store is intended to provide data for the RecommendedVideosComponent.
  11  */
  12 @Injectable()
  13 export class RecommendedVideosStore {
  14   public readonly recommendations$: Observable<Video[]>
  15   public readonly hasRecommendations$: Observable<boolean>
  16   private readonly requestsForLoad$$ = new ReplaySubject<RecommendationInfo>(1)
  17
  18   constructor (
  19     @Inject(RecentVideosRecommendationService) private recommendations: RecommendationService
  20   ) {
  21     this.recommendations$ = this.requestsForLoad$$.pipe(
  22       switchMap(requestedRecommendation => recommendations.getRecommendations(requestedRecommendation)
  23         .pipe(take(1))
  24       ))
  25     this.hasRecommendations$ = this.recommendations$.pipe(
  26       map(otherVideos => otherVideos.length > 0)
  27     )
  28   }
  29
  30   requestNewRecommendations (recommend: RecommendationInfo) {
  31     this.requestsForLoad$$.next(recommend)
  32   }
  33 }