private void ThrowIdentityConflict(InternalEntityEntry entry)
        {
            if (entry.EntityType.IsOwned())
            {
                if (_sensitiveLoggingEnabled)
                {
                    throw new InvalidOperationException(
                              CoreStrings.IdentityConflictOwnedSensitive(
                                  entry.EntityType.DisplayName(),
                                  entry.BuildCurrentValuesString(Key.Properties)));
                }

                throw new InvalidOperationException(
                          CoreStrings.IdentityConflictOwned(
                              entry.EntityType.DisplayName(),
                              Property.Format(Key.Properties)));
            }

            if (_sensitiveLoggingEnabled)
            {
                throw new InvalidOperationException(
                          CoreStrings.IdentityConflictSensitive(
                              entry.EntityType.DisplayName(),
                              entry.BuildCurrentValuesString(Key.Properties)));
            }

            throw new InvalidOperationException(
                      CoreStrings.IdentityConflict(
                          entry.EntityType.DisplayName(),
                          Property.Format(Key.Properties)));
        }
        /// <summary>
        ///     This API supports the Entity Framework Core infrastructure and is not intended to be used
        ///     directly from your code. This API may change or be removed in future releases.
        /// </summary>
        protected virtual void Add([NotNull] TKey key, [NotNull] InternalEntityEntry entry)
        {
            InternalEntityEntry existingEntry;

            if (_identityMap.TryGetValue(key, out existingEntry))
            {
                if (existingEntry != entry)
                {
                    if (_sensitiveLoggingEnabled)
                    {
                        throw new InvalidOperationException(
                                  CoreStrings.IdentityConflictSensitive(
                                      entry.EntityType.DisplayName(),
                                      entry.BuildCurrentValuesString(Key.Properties)));
                    }

                    throw new InvalidOperationException(
                              CoreStrings.IdentityConflict(
                                  entry.EntityType.DisplayName(),
                                  Property.Format(Key.Properties)));
                }
            }
            else
            {
                AddInternal(key, entry);
            }
        }
        private void InitialFixup(
            InternalEntityEntry entry,
            ISet <IForeignKey> handledForeignKeys,
            bool fromQuery)
        {
            var entityType   = (EntityType)entry.EntityType;
            var stateManager = entry.StateManager;

            foreach (var foreignKey in entityType.GetForeignKeys())
            {
                if (handledForeignKeys == null ||
                    !handledForeignKeys.Contains(foreignKey))
                {
                    var principalEntry = stateManager.GetPrincipal(entry, foreignKey);
                    if (principalEntry != null)
                    {
                        if (!foreignKey.PrincipalEntityType.IsAssignableFrom(principalEntry.EntityType))
                        {
                            if (_sensitiveLoggingEnabled)
                            {
                                throw new InvalidOperationException(CoreStrings.IncompatiblePrincipalEntrySensitive(
                                                                        entry.BuildCurrentValuesString(foreignKey.Properties),
                                                                        entityType.DisplayName(),
                                                                        entry.BuildOriginalValuesString(entityType.FindPrimaryKey().Properties),
                                                                        principalEntry.EntityType.DisplayName(),
                                                                        foreignKey.PrincipalEntityType.DisplayName()));
                            }

                            throw new InvalidOperationException(CoreStrings.IncompatiblePrincipalEntry(
                                                                    Property.Format(foreignKey.Properties),
                                                                    entityType.DisplayName(),
                                                                    principalEntry.EntityType.DisplayName(),
                                                                    foreignKey.PrincipalEntityType.DisplayName()));
                        }

                        // Set navigation to principal based on FK properties
                        SetNavigation(entry, foreignKey.DependentToPrincipal, principalEntry);

                        // Add this entity to principal's collection, or set inverse for 1:1
                        ToDependentFixup(entry, principalEntry, foreignKey);
                    }
                }
            }

            foreach (var foreignKey in entityType.GetReferencingForeignKeys())
            {
                if (handledForeignKeys == null ||
                    !handledForeignKeys.Contains(foreignKey))
                {
                    var dependents = stateManager.GetDependents(entry, foreignKey);
                    if (foreignKey.IsUnique)
                    {
                        var dependentEntry = dependents.FirstOrDefault();
                        if (dependentEntry != null)
                        {
                            // Set navigations to and from principal entity that is indicated by FK
                            SetNavigation(entry, foreignKey.PrincipalToDependent, dependentEntry);
                            SetNavigation(dependentEntry, foreignKey.DependentToPrincipal, entry);
                        }
                    }
                    else
                    {
                        foreach (var dependentEntry in dependents)
                        {
                            // Add to collection on principal indicated by FK and set inverse navigation
                            AddToCollection(entry, foreignKey.PrincipalToDependent, dependentEntry);

                            SetNavigation(dependentEntry, foreignKey.DependentToPrincipal, entry);
                        }
                    }
                }
            }

            // If the new state is from a query then we are going to assume that the FK value is the source of
            // truth and not attempt to ascertain relationships from navigation properties
            if (!fromQuery)
            {
                var setModified = entry.EntityState != EntityState.Unchanged &&
                                  entry.EntityState != EntityState.Modified;

                foreach (var foreignKey in entityType.GetReferencingForeignKeys())
                {
                    var principalToDependent = foreignKey.PrincipalToDependent;
                    if (principalToDependent != null)
                    {
                        var navigationValue = entry[principalToDependent];
                        if (navigationValue != null)
                        {
                            if (principalToDependent.IsCollection())
                            {
                                var dependents = ((IEnumerable)navigationValue).Cast <object>().ToList();
                                foreach (var dependentEntity in dependents)
                                {
                                    var dependentEntry = stateManager.TryGetEntry(dependentEntity);
                                    if (dependentEntry == null ||
                                        dependentEntry.EntityState == EntityState.Detached)
                                    {
                                        // If dependents in collection are not yet tracked, then save them away so that
                                        // when we start tracking them we can come back and fixup this principal to them
                                        stateManager.RecordReferencedUntrackedEntity(dependentEntity, principalToDependent, entry);
                                    }
                                    else
                                    {
                                        FixupToDependent(entry, dependentEntry, foreignKey, setModified);
                                    }
                                }
                            }
                            else
                            {
                                var targetEntityType = principalToDependent.GetTargetType();
                                var dependentEntry   = stateManager.TryGetEntry(navigationValue, targetEntityType);
                                if (dependentEntry == null ||
                                    dependentEntry.EntityState == EntityState.Detached)
                                {
                                    // If dependent is not yet tracked, then save it away so that
                                    // when we start tracking it we can come back and fixup this principal to it
                                    stateManager.RecordReferencedUntrackedEntity(navigationValue, principalToDependent, entry);
                                }
                                else
                                {
                                    FixupToDependent(entry, dependentEntry, foreignKey, setModified);
                                }
                            }
                        }
                    }
                }

                foreach (var foreignKey in entityType.GetForeignKeys())
                {
                    var dependentToPrincipal = foreignKey.DependentToPrincipal;
                    if (dependentToPrincipal != null)
                    {
                        var navigationValue = entry[dependentToPrincipal];
                        if (navigationValue != null)
                        {
                            var targetEntityType = dependentToPrincipal.GetTargetType();
                            var principalEntry   = stateManager.TryGetEntry(navigationValue, targetEntityType);
                            if (principalEntry == null ||
                                principalEntry.EntityState == EntityState.Detached)
                            {
                                // If principal is not yet tracked, then save it away so that
                                // when we start tracking it we can come back and fixup this dependent to it
                                stateManager.RecordReferencedUntrackedEntity(navigationValue, dependentToPrincipal, entry);
                            }
                            else
                            {
                                FixupToPrincipal(entry, principalEntry, foreignKey, setModified);
                            }
                        }
                    }
                }

                // If the entity was previously referenced while it was still untracked, go back and do the fixup
                // that we would have done then now that the entity is tracked.
                foreach (var danglerEntry in stateManager.GetRecordedReferers(entry.Entity, clear: true))
                {
                    DelayedFixup(danglerEntry.Item2, danglerEntry.Item1, entry);
                }
            }
        }