//TODO: refactor this method
public IAggregateRoot <TEventType> Apply(TEventType evnt)
{
var restoredEntity = _eventStream.Aggregate(_entity, (acc, next) => When(acc.Appled().Result(), (TEventType)next));
var entity = restoredEntity == null ? _entity : new Applied <TEntity>(restoredEntity.Appled().Result());
var applied = entity.Appled();
return(new FakeAggregateRoot <TEntity, TEventType>(
When,
When(applied.Result(), evnt),
applied
.Events()
.Concat(new [] { (IDomainEvent)evnt.Content() })
));
}