import {Injectable} from '@angular/core';
import {Observable} from 'rxjs/internal/Observable';
import {throwError} from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class ErrorLoggerService {
  constructor() {
  }

  /**
   * Handle Http operation that failed.
   * Let the app continue.
   * @param operation - name of the operation that failed
   * @param result - optional value to return as the observable result
   */
  public handleError<T>(serviceName = 'error-logger', operation = 'operation', result?: T) {
    return (error: any): Observable<T> => {

      // TODO: send the error to remote logging infrastructure
      console.error(error); // log to console instead

      // TODO: better job of transforming error for user consumption
      this.log(serviceName, `${operation} failed: ${error.message}`);

      // // Let the app keep running by returning an empty result.
      // return of(result as T);
      return throwError(error);
    };
  }

  public log(serviceName = 'error-logger', message: string) {
    console.log(serviceName + 'Service: ' + message);
  }
}