public static void Validate(BookItemStatus itemStatus, BookItemStatus newStatus)
{
switch (itemStatus)
{
case BookItemStatus.Read:
if (newStatus == BookItemStatus.Read)
{
break;
}
throw new CannotChangeStatusException(itemStatus, newStatus);
case BookItemStatus.Reading:
case BookItemStatus.StartedButPostponed:
if (newStatus == BookItemStatus.ToReading)
{
throw new CannotChangeStatusException(itemStatus, newStatus);
}
break;
case BookItemStatus.ToReading:
if (newStatus == BookItemStatus.Read || newStatus == BookItemStatus.StartedButPostponed)
{
throw new CannotChangeStatusException(itemStatus, newStatus);
}
break;
default:
throw new ArgumentOutOfRangeException(nameof(itemStatus), itemStatus.ToString("G"), null);
}
}