import {
  HttpClient,
  HttpErrorResponse
} from '@angular/common/http';
import { Observable } from 'rxjs';
import { catchError } from 'rxjs/operators';

import { SharedConstants } from '../constants/shared.constants';

export class ApiService<T> {
  baseUrl: string = SharedConstants.END_POINT_URL;
  entityUrl: string;

  setUrl(entityUrl: string): void {
    this.entityUrl = entityUrl;
  }

  getUrl(): string {
    return this.entityUrl;
  }

  constructor(protected http: HttpClient) {
  }

  get(): Observable<any> {
    return this.http.get<Object[]>(this.baseUrl + this.entityUrl);
  }

  getById(id: number): Observable<any> {
    return this.http.get<Object>(this.baseUrl + this.entityUrl + '/'+id);
  }

  create(data: any): Observable<Object> {

    return this.http.post<Object>(this.baseUrl + this.entityUrl, data);
  }

  update(obj: Object): Observable<Object> {

    return this.http.put<Object>(this.baseUrl + this.entityUrl, obj);
  }

  deleteById(id: number): Observable<number> {

    return this.http.delete<number>(this.baseUrl + this.entityUrl+"/" + id);
  }

  test() {}

  private handleError(error: HttpErrorResponse) {
    if (error.error instanceof ErrorEvent) {
      // A client-side or network error occurred. Handle it accordingly.
      console.error('An error occurred:', error.error.message);
    } else {
      // The backend returned an unsuccessful response code.
      // The response body may contain clues as to what went wrong,
      console.error(
        `Backend returned code ${error.status}, ` + `body was: ${error.error}`
      );
    }
    // return an observable with a user-facing error message
    throw new Error('Something bad happened; please try again later.');
  }
}