public async Task SavePreferenceAsync(PreferenceDto preference)
{
var previousPreference = await _preferenceRepository.GetPreferenceAsync(preference.EmployeeId, preference.DrinkId);
await _preferenceRepository.SavePreferenceAsync(
Preference.Create(
preference.EmployeeId,
preference.DrinkId,
new DrinkPreference(
preference.Amounts.Select(a => new IngredientAmount(a.DrinkIngredientId, a.Amount)),
preference.Mug
),
preferenceId: previousPreference?.PreferenceId ?? 0));
}