import { Injectable } from '@angular/core';
import { BehaviorSubject, Observable } from 'rxjs';
import { HttpErrorResponse } from '@angular/common/http';
import { LoadingService } from '../loading';
import { filter } from 'rxjs/operators';
import { NavigationStart, Router } from '@angular/router';

@Injectable({ providedIn: 'root' })
export class ErrorService {
    readonly error$: Observable<HttpErrorResponse | undefined>;
    private readonly _errorEvent$ = new BehaviorSubject<HttpErrorResponse | undefined>(undefined);

    constructor(private readonly _loadingService: LoadingService, private readonly _router: Router) {
        this.error$ = this._errorEvent$.asObservable();
        _router.events.pipe(filter(event => event instanceof NavigationStart)).subscribe(() => {
            this.clear();
        });
    }

    set(error: HttpErrorResponse): void {
        this._loadingService.stop();
        this._errorEvent$.next(error);
    }

    clear(): void {
        this._errorEvent$.next(undefined);
    }
}