import { Injectable } from '@angular/core';
import { HotelModel } from "./hotel.model";
import {Observable, of, Subject} from "rxjs/index";
import {HttpClient, HttpHeaders} from "@angular/common/http";
import {catchError, map, tap} from "rxjs/internal/operators";

@Injectable({
  providedIn: 'root'
})
export class HotelService {
  private hotelsUrl = 'api/hotels';  // URL to web api
  private hotels: HotelModel[] = [];
  constructor(private http: HttpClient) { }

  httpOptions = {
    headers: new HttpHeaders({ 'Content-Type': 'application/json' })
  };

  getHotels():Observable<HotelModel[]>{
    return this.http.get<HotelModel[]>(this.hotelsUrl).pipe(
      catchError(this.handleError<HotelModel[]>('get hotels', []) )
    )
  }

  getHotel(id: number | string){    // or you can go 2nd method which is just below
    return this.getHotels().pipe(
      map((hotels:HotelModel[]) => hotels.find(hotel => hotel.id === +id ))
    );
  }

  updateHotelInDetailSection(hotel:HotelModel):Observable<any>{
    return this.http.put(this.hotelsUrl, hotel, this.httpOptions).pipe(
      catchError(this.handleError<any>('update hotel'))
    )
  }

  updateHotel(id:number, hotel:HotelModel):Observable<any>{
    const url = `${this.hotelsUrl}/${id}`;
    return this.http.put<HotelModel>(url, hotel, this.httpOptions).pipe(
      tap(updatedHotel => console.log('hotel updated', url)),
      catchError(this.handleError<any>('updateHotel'))
    )
  }


  private handleError<T> (operation = 'operation', result?: T) {
  return (error: any): Observable<T> => {
    console.error(error); // log to console instead
    return of(result as T);
    };
  }

}

import { Component, OnInit } from '@angular/core';
import { FormBuilder, FormGroup } from "@angular/forms";
import { HotelService} from "../hotel.service";
import {ActivatedRoute, ParamMap, Params, Router} from "@angular/router";
import { switchMap } from "rxjs/internal/operators";
import { HotelModel } from "../hotel.model";

@Component({
  selector: 'app-hotel-edit',
  templateUrl: './hotel-edit.component.html',
  styleUrls: ['./hotel-edit.component.css']
})
export class HotelEditComponent implements OnInit {
  hotelEditForm:FormGroup;
  editMode;
  id:number;
  hotel:HotelModel;
  constructor(
              private fb: FormBuilder,
              private hotelService:HotelService,
              private route:ActivatedRoute,
              private router:Router,

              ) { }

  ngOnInit() {
    this.route.params.subscribe(
      (params: Params) => {
        this.id = +params['id'];
        this.editMode = params['id'] != null;
        this.initHotelForm()
    }
    );

    this.hotelEditForm = this.fb.group({
    name:[''],
    price:[''],
    imagePath:[''],
    description:[''],
    city:[''],
    address:['']
  })
  }

  private initHotelForm(){
    let hotelName = '';
    let hotelPrice:number=null;
    let hotelImagePath = '';
    let hotelDescription = '';
    let hotelCity = '';
    let hotelAddress = '';

    if(this.editMode){
       this.hotelService.getHotel(this.id).subscribe(data => {
         const hotel = data;
         hotelName = hotel.name;
         hotelPrice = hotel.price;
         hotelImagePath = hotel.imagePath;
         hotelDescription = hotel.description;
         hotelCity = hotel.city;
         hotelAddress = hotel.address;


       this.hotelEditForm.controls['name'].setValue(hotelName);
       this.hotelEditForm.controls['imagePath'].setValue(hotelImagePath);
       this.hotelEditForm.controls['price'].setValue(hotelPrice);
       this.hotelEditForm.controls['description'].setValue(hotelDescription);
       this.hotelEditForm.controls['address'].setValue(hotelCity);
       this.hotelEditForm.controls['address'].setValue(hotelAddress);

      });
    }
  }
  onUpdateHotel(){
    if(this.editMode){
      this.hotelService.updateHotel(this.id, this.hotelEditForm.value).subscribe(()=>
        this.router.navigate(['/hotels'], { relativeTo: this.route })
      )
    }
  }

}