import { Injectable } from '@angular/core';
import { HttpClient, HttpHeaders } from '@angular/common/http';
import { ErrorLoggerService } from '../core/error-logger.service';
import { catchError } from 'rxjs/operators';
import { Observable } from 'rxjs/internal/Observable';
import { SaleCategory } from '../core/sale-category';

const httpOptions = {
  headers: new HttpHeaders({'Content-Type': 'application/json'})
};
const url = '/api/sale-categories';
const serviceName = 'SaleCategoryService';

@Injectable({
  providedIn: 'root'
})
export class SaleCategoryService {
  constructor(private http: HttpClient, private log: ErrorLoggerService) {
  }

  get(id: string): Observable<SaleCategory> {
    const getUrl: string = (id === null) ? url : `${url}/${id}`;
    return <Observable<SaleCategory>>this.http.get<SaleCategory>(getUrl)
      .pipe(
        catchError(this.log.handleError(serviceName, `get id=${id}`))
      );
  }

  list(): Observable<SaleCategory[]> {
    return <Observable<SaleCategory[]>>this.http.get<SaleCategory[]>(`${url}/list`)
      .pipe(
        catchError(this.log.handleError(serviceName, 'list'))
      );
  }

  listForDiscount(): Observable<{name: string, discount: number}[]> {
    return <Observable<{name: string, discount: number}[]>>this.http.get<{name: string, discount: number}[]>(`${url}/for-discount`)
      .pipe(
        catchError(this.log.handleError(serviceName, 'list'))
      );
  }

  save(saleCategory: SaleCategory): Observable<SaleCategory> {
    return <Observable<SaleCategory>>this.http.post<SaleCategory>(url, saleCategory, httpOptions)
      .pipe(
        catchError(this.log.handleError(serviceName, 'save'))
      );
  }

  update(saleCategory: SaleCategory): Observable<SaleCategory> {
    return <Observable<SaleCategory>>this.http.put<SaleCategory>(`${url}/${saleCategory.id}`, saleCategory, httpOptions)
      .pipe(
        catchError(this.log.handleError(serviceName, 'update'))
      );
  }

  saveOrUpdate(saleCategory: SaleCategory): Observable<SaleCategory> {
    if (!saleCategory.id) {
      return this.save(saleCategory);
    } else {
      return this.update(saleCategory);
    }
  }

  delete(id: string): Observable<SaleCategory> {
    return <Observable<SaleCategory>>this.http.delete<SaleCategory>(`${url}/${id}`, httpOptions)
      .pipe(
        catchError(this.log.handleError(serviceName, 'delete'))
      );
  }
}