import { Injectable, inject } from "@angular/core";
import { PublicationRestService } from "../../core/rest-services/publications/publication.rest-service";
import { BehaviorSubject, Observable } from "rxjs";
import { MatSnackBar } from "@angular/material/snack-bar"
import { Publication } from "../../core/rest-services/publications/model/publication";

@Injectable()
export class HomeService {
    private publicationRestService = inject(PublicationRestService);
    private snackBar = inject(MatSnackBar);

    private publicationsSubject = new BehaviorSubject<Publication[]>([]);
    private isLoadingSubject = new BehaviorSubject<boolean>(false);

    get isLoading$(): Observable<boolean> {
        return this.isLoadingSubject.asObservable();
    }

    get publications$(): Observable<Publication[]> {
        return this.publicationsSubject.asObservable();
    }

    startLatestPublicationsRetrieving(): void {
        this.isLoadingSubject.next(true);

        this.publicationRestService.getLatest()
            .then(publications => this.publicationsSubject.next(publications))
            .catch(error => {
                this.snackBar.open('An error occurred while retrieving latest publications...');
                console.error('An error occurred while retrieving latest publications...', error);
            })
            .finally(() => this.isLoadingSubject.next(false));
    }
}