astronaut.component.ts

export class AstronautComponent extends BaseComponent {
  @Input() astronaut: string;
  mission = '<no mission announced>';
  confirmed = false;
  announced = false;

  constructor(private missionService: MissionService) {
    super();
    
    missionService.missionAnnounced$
      .takeUntil(this.destroyed$)
      .subscribe(
        mission => {
          this.mission = mission;
          this.announced = true;
          this.confirmed = false;
        });
  }

  confirm() {
    this.confirmed = true;
    this.missionService.confirmMission(this.astronaut);
  }
}