import { EventEmitter, Injectable } from '@angular/core';
import { ActivatedRouteSnapshot, Resolve, RouterStateSnapshot } from "@angular/router";
import { HttpClient } from "@angular/common/http";
import { Observable } from "rxjs/internal/Observable";

import { environment } from "../../environments/environment";
import { Awardee } from "./awardee";

@Injectable({
  providedIn: 'root'
})
export class AwardeeService implements Resolve<Array<Awardee>> {

  private apiEndPoint = `${environment.apiUrl}/awardee`;
  private apiEndPointImage = `${environment.apiUrl}/awardee-image`;
  private cachedAwardees: Array<Awardee> = [];

  public changed: EventEmitter<Array<Awardee>> = new EventEmitter<Array<Awardee>>();

  constructor(private httpClient: HttpClient) {
  }

  public resolve(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Promise<Array<Awardee>> {
    return this.getJudges().toPromise();
  }

  public getJudges(): Observable<Array<Awardee>> {
    return this.httpClient.get<Array<Awardee>>(this.apiEndPoint);
  }

  get awardees(): Array<Awardee> {
    return this.cachedAwardees;
  }

  set awardees(judges: Array<Awardee>) {
    this.cachedAwardees = judges;
    this.triggerChange();
  }

  public triggerChange() {
    this.changed.emit(this.cachedAwardees);
  }

  public persist(awardee: Awardee): Observable<Awardee> {
    return awardee.id === null
      ? this.create(awardee)
      : this.update(awardee);
  }

  public create(awardee: Awardee): Observable<Awardee> {
    return this.httpClient.post<Awardee>(this.apiEndPoint, awardee);
  }

  public update(awardee: Awardee): Observable<Awardee> {
    return this.httpClient.put<Awardee>(`${this.apiEndPoint}/${awardee.id}`, awardee);
  }

  public saveImage(slug: string, image: File, type: string) {
    let form = new FormData();
    form.append('image', image);
    return this.httpClient.post<Awardee>(`${this.apiEndPointImage}/${type}/${slug}`, form);
  }

  public delete(id: number): Observable<boolean> {
    return this.httpClient.delete<boolean>(`${this.apiEndPoint}/${id}`);
  }
}