import { ErrorObservable } from 'rxjs/observable/ErrorObservable';
import { Response } from '@angular/http';
import { Observable } from 'rxjs';
import { HALConfig } from '../hal.config';
import { ApiErrorResponse } from './api-error.model';
import { IApiErrorHandler } from './api-error-handler.interface';

export class ApiErrorHandler implements IApiErrorHandler {

  public handle(errorResponse: Response): ErrorObservable {
    const json: any = errorResponse.json();
    const messages: string[] = [];
    if (json[HALConfig.embedded]) {
      const embedded: Array<{name: string, message: string}> = json[HALConfig.embedded];
      for (const errorJson of embedded) {
        messages.push(errorJson.message);
      }
    }
    const errors: Error[] = messages.map((message: string) => new Error(message));
    return Observable.throw(new ApiErrorResponse(errorResponse.status, errorResponse.statusText, errors));
  }
}