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

import { DELIVERY_DATE_API, ERROR_MESSAGE, LOCALE } from '../../app.constants';
import { map } from 'rxjs/operators/map';
import { filter } from 'rxjs/operators';
import { ErrorStore } from '../stores/error.store';
import { BehaviorSubject } from 'rxjs';
import { AppStateStore } from '../../providers/stores/app-state.store';
import { DatePipe } from '@angular/common';

export interface IDeliveryDates {
  EarliestStandardElectronicScheduleForDate: string;
}

@Injectable()
export class DeliveryDateService {
  private publisher = new BehaviorSubject<string>(null);
  public earliestStandardElectronicScheduleForDate$ = this.publisher.asObservable();
  public expectedDeliveryDate$: Observable<string>;
  private datePipe = new DatePipe(LOCALE);
  expectedDeliveryDateValue: Date;
  expectedDeliveryDate: string;

  constructor(
    private http: HttpClient,
    private errorService: ErrorStore,
  ) {
    this.expectedDeliveryDate$ = this.earliestStandardElectronicScheduleForDate$.pipe(
      map((response) => {
      this.expectedDeliveryDateValue = new Date(response);
      this.expectedDeliveryDateValue.setDate( this.expectedDeliveryDateValue.getDate() + 2 );
      return this.datePipe.transform(new Date(this.expectedDeliveryDateValue), 'MM/dd/yyyy');
      }));
  }

   loadDeliveryDate(domain: string): Observable<string> {
    return this.http
      .get<IDeliveryDates>(`${DELIVERY_DATE_API}?domain=${domain}`)
      .pipe(
        map((response) => {
          filter((response) => !!response),
          console.log(response);
          this.publisher.next(response.EarliestStandardElectronicScheduleForDate);
          return response.EarliestStandardElectronicScheduleForDate;
        }),
        catchError((error) => {
          const title = 'Failed to get delivery dates.';
          return this.handleError(error, title);
        })
      );
  }

  private handleError(error: any, title: string, msg: string = null) {
    let message = ERROR_MESSAGE;
    if (!!msg) {
      message = msg;
    }
    this.errorService.showError(title, message);
    return Observable.of(null);
  }
}