public override void Handle(EditThemeCommand command)
{
Theme themeToChange = _dbContext.Themes.Find(command.Id);
if (themeToChange == null)
{
_result = new InvalidResult()
.WithError("No theme of this id has been found.");
}
Theme parent = _dbContext.Themes.Find(command.ParentId);
themeToChange.ChangeName(command.Name);
themeToChange.ChangeParent(parent);
_dbContext.Themes.Update(themeToChange);
_dbContext.SaveChanges();
_result = new SuccessResult();
}