import { Injectable } from '@angular/core';

import { Http, Response, Headers } from '@angular/http';
import { Observable } from 'rxjs/Rx';
import 'rxjs/add/operator/map'

import { Beer } from './beer';


@Injectable()
export class BeerService {
  private baseUrl: string = 'http://api.brewerydb.com/v2';
  private keyUrl: string = '?key=5d7547f6f876fced03cb9166dff0e578';

  constructor(private http : Http){}

  get(id: string): Observable<Beer> {
    let beer$ = this.http
      .get(
          dbUrl(`${this.baseUrl}/beer/${id}${this.keyUrl}`)
            , {headers: this.getHeaders()})
      .map(mapBeer);
    return beer$;
  }

  getAll(): Observable<Beer[]>{
    let beers$ = this.http
      .get(
          dbUrl(`${this.baseUrl}/beers${this.keyUrl}&styleId=1`)
            , {headers: this.getHeaders()})
      .map(mapBeers);
    return beers$;
  }

  private getHeaders(){
    let headers = new Headers();
    headers.append('Accept', 'application/json');
    return headers;
  }
}

function mapBeers(response:Response): Beer[]{
  // The response of the API has a results
  // property with the actual results
  return response.json().data.map(toBeer)
}

function mapBeer(response:Response): Beer{
  // toPerson looks just like in the previous example
  return toBeer(response.json().data);
}

function toBeer(r:any): Beer{
  let beer = <Beer>({
    id: r.id,
    name: r.name,
    description: (r.description || "No description")
  });
  console.log('Parsed beer:', beer);
  return beer;
}

function dbUrl(url:string) : string
{
  return 'http://kvewijk.nl/dbprox/?path=' + encodeURIComponent(url);
}