/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
import {Injectable} from '@angular/core';
import {Headers, Http, Response, ResponseContentType} from '@angular/http';
import {Observable} from 'rxjs/Observable';
import {Store} from '@ngrx/store';
import * as fromRoot from '../../store';
import {AUTHORIZATION_HEADER, TENANT_HEADER, USER_HEADER} from '../http/http.service';
import {State} from '../../store/security/authentication.reducer';

@Injectable()
export class ImageService {

  constructor(private http: Http, private store: Store<fromRoot.State>) {
  }

  public getImage(url: string): Observable<Blob> {
    return this.store.select(fromRoot.getAuthenticationState)
      .take(1)
      .map(this.mapHeader)
      .switchMap((headers: Headers) =>
        this.http.get(url, {
          responseType: ResponseContentType.Blob,
          headers: headers
        })
          .map((response: Response) => response.blob())
          .catch(() => Observable.empty()));
  }
  

  private mapHeader(authenticationState: State): Headers {
    const headers = new Headers();

    headers.set('Accept', 'application/json');

    headers.set(TENANT_HEADER, authenticationState.tenant);
    headers.set(USER_HEADER, authenticationState.username);
    headers.set(AUTHORIZATION_HEADER, authenticationState.authentication.accessToken);

    return headers;
  }

}