public Dictionary <WebResourceName, string> DisposeAndGetLeftovers()
        {
            var result = _inner.DisposeAndGetLeftovers();

            _logger.LogEntitiesExists(result.Keys);
            return(result);
        }
        private async Task <IReadOnlyList <IEntitySyncStateContext <TAtypeEntityId, TAtypeEntityVersion, TAtypeEntity, TBtypeEntityId, TBtypeEntityVersion, TBtypeEntity, TContext> > > CreateEntitySyncStateContexts(
            IEntityContainer <TAtypeEntityId, TAtypeEntity, TContext> aEntities,
            IEntityContainer <TBtypeEntityId, TBtypeEntity, TContext> bEntities,
            IEnumerable <IEntityRelationData <TAtypeEntityId, TAtypeEntityVersion, TBtypeEntityId, TBtypeEntityVersion> > knownEntityRelations,
            IEntityStateCollection <TAtypeEntityId, TAtypeEntityVersion> aStates,
            IEntityStateCollection <TBtypeEntityId, TBtypeEntityVersion> bStates,
            ISynchronizationLogger logger,
            TContext synchronizationContext,
            ISynchronizationInterceptor <TAtypeEntityId, TAtypeEntityVersion, TAtypeEntity, TBtypeEntityId, TBtypeEntityVersion, TBtypeEntity, TContext> interceptor)
        {
            var entitySynchronizationContexts = new List <IEntitySyncStateContext <TAtypeEntityId, TAtypeEntityVersion, TAtypeEntity, TBtypeEntityId, TBtypeEntityVersion, TBtypeEntity, TContext> >();

            var aDeltaLogInfo = new VersionDeltaLoginInformation();
            var bDeltaLogInfo = new VersionDeltaLoginInformation();

            foreach (var knownEntityRelationData in knownEntityRelations)
            {
                (var aState, var aRepositoryVersion) = aStates.RemoveState(knownEntityRelationData.AtypeId, knownEntityRelationData.AtypeVersion);
                (var bState, var bRepositoryVersion) = bStates.RemoveState(knownEntityRelationData.BtypeId, knownEntityRelationData.BtypeVersion);

                entitySynchronizationContexts.Add(new EntitySyncStateContext <TAtypeEntityId, TAtypeEntityVersion, TAtypeEntity, TBtypeEntityId, TBtypeEntityVersion, TBtypeEntity, TContext>(
                                                      CreateInitialSyncState(knownEntityRelationData, aState, bState, aRepositoryVersion, bRepositoryVersion, aDeltaLogInfo, bDeltaLogInfo)));
            }

            var newAVersions = aStates.DisposeAndGetLeftovers();
            var newBVersions = bStates.DisposeAndGetLeftovers();

            await _atypeRepository.VerifyUnknownEntities(newAVersions, synchronizationContext);

            await _btypeRepository.VerifyUnknownEntities(newBVersions, synchronizationContext);

            if (newAVersions.Count > 0 && newBVersions.Count > 0)
            {
                s_logger.Info($"Performing entity matching with {newAVersions.Count} Atype and {newBVersions.Count} Btype entities.");

                var matchingEntites = _initialEntityMatcher.FindMatchingEntities(
                    _entityRelationDataFactory,
                    await aEntities.GetTransformedEntities(newAVersions.Keys, logger.ALoadEntityLogger, synchronizationContext, e => _aMatchDataFactory.CreateMatchData(e.Entity)),
                    await bEntities.GetTransformedEntities(newBVersions.Keys, logger.BLoadEntityLogger, synchronizationContext, e => _bMatchDataFactory.CreateMatchData(e.Entity)),
                    newAVersions,
                    newBVersions);

                foreach (var knownEntityRelationData in matchingEntites)
                {
                    newAVersions.Remove(knownEntityRelationData.AtypeId);
                    newBVersions.Remove(knownEntityRelationData.BtypeId);
                    var entitySyncState = _initialSyncStateCreationStrategy.CreateFor_Unchanged_Unchanged(knownEntityRelationData);
                    entitySynchronizationContexts.Add(new EntitySyncStateContext <TAtypeEntityId, TAtypeEntityVersion, TAtypeEntity, TBtypeEntityId, TBtypeEntityVersion, TBtypeEntity, TContext>(entitySyncState));
                    aDeltaLogInfo.IncUnchanged();
                    bDeltaLogInfo.IncUnchanged();
                }

                s_logger.Info("Entity matching finished.");
            }

            foreach (var newA in newAVersions)
            {
                var syncState = _initialSyncStateCreationStrategy.CreateFor_Added_NotExisting(newA.Key, newA.Value);
                entitySynchronizationContexts.Add(new EntitySyncStateContext <TAtypeEntityId, TAtypeEntityVersion, TAtypeEntity, TBtypeEntityId, TBtypeEntityVersion, TBtypeEntity, TContext>(syncState));
            }

            foreach (var newB in newBVersions)
            {
                var syncState = _initialSyncStateCreationStrategy.CreateFor_NotExisting_Added(newB.Key, newB.Value);
                entitySynchronizationContexts.Add(new EntitySyncStateContext <TAtypeEntityId, TAtypeEntityVersion, TAtypeEntity, TBtypeEntityId, TBtypeEntityVersion, TBtypeEntity, TContext>(syncState));
            }

            interceptor.TransformInitialCreatedStates(entitySynchronizationContexts, _syncStateFactory);

            // all the leftovers in newAVersions and newBVersions must be the added ones
            aDeltaLogInfo.IncAdded(newAVersions.Count);
            bDeltaLogInfo.IncAdded(newBVersions.Count);
            s_logger.InfoFormat("Atype delta: {0}", aDeltaLogInfo);
            s_logger.InfoFormat("Btype delta: {0}", bDeltaLogInfo);
            logger.LogDeltas(aDeltaLogInfo, bDeltaLogInfo);

            return(entitySynchronizationContexts);
        }