public ExperienceViewModel IncrementExperience(int quantity) { var previousExperience = _experienceRepository.CurrentExperience(); var actualExperience = previousExperience + quantity; if (HasReachedNewLevel(actualExperience)) { LevelUp(actualExperience); } else { _experienceRepository.SetExperience(actualExperience); } return(BuildCurrentExperienceViewModel()); }