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

@Injectable()
export class SearchPublicationsService {
    private publicationRestService = inject(PublicationRestService);
    private publicationsSubject = new BehaviorSubject<Publication[]>([]);
    private isLoadingSubject = new BehaviorSubject<boolean>(false);
    private isLoadedSubject = new BehaviorSubject<boolean>(false);
    private snackBar = inject(MatSnackBar);

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

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

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

    loadPublications(searchCriteria: string): void {
         this.isLoadingSubject.next(true);
         this.isLoadedSubject.next(false);
         this.publicationsSubject.next([]);

         this.publicationRestService.search(searchCriteria)
            .then(publications => {
                this.publicationsSubject.next(publications);
            })
            .catch(error => {
                if (error.status !== 404) {
                    const errorMessage = $localize`An error occured while retrieving publications.`;
                    console.error(errorMessage, error);
                    this.snackBar.open(errorMessage, $localize`Close`, { duration: 5000 });
                }
            })
            .finally(() => {
                this.isLoadingSubject.next(false);
                this.isLoadedSubject.next(true);
            });
    }
}