private Address AttachWithRelations(Address entity, InsertMode insertMode = InsertMode.Attach, MergeOption mergeOption = MergeOption.AppendOnly, List <object> referenceTrackingList = null)
{
#region iteration tracking
if (ReferenceEquals(null, referenceTrackingList))
{
referenceTrackingList = new List <object>();
}
if (referenceTrackingList.Contains(entity))
{
return(_addresses.GetExisting(entity));
}
else
{
referenceTrackingList.Add(entity);
}
#endregion
#region add/attach entity
Address existingEntity = null;
switch (insertMode)
{
case InsertMode.Add:
existingEntity = _addresses.Add(entity);
break;
case InsertMode.Attach:
existingEntity = _addresses.Attach(entity);
break;
default:
throw new Exception(string.Format("Implementation Exception: missing action for {0}", insertMode));
}
if (!ReferenceEquals(null, existingEntity) && ReferenceEquals(existingEntity, entity))
{
return(existingEntity);
}
#endregion
#region attach relations recursively
if (!ReferenceEquals(null, entity.Customers))
{
// register relation's collection changed event if entity is new to context
if (ReferenceEquals(null, existingEntity))
{
entity.Customers.CollectionChanged += On_address_customers_collectionChanged;
}
// attach related entities to context
if (entity.Customers.Count > 0)
{
foreach (var item in entity.Customers.ToArray())
{
var existingRelatedEntity = (Customer)AttachWithRelations(item, insertMode, mergeOption, referenceTrackingList);
// update relation if entity is new to context or relation is new to entity
if (ReferenceEquals(null, existingEntity) || !existingEntity.Customers.Contains(item))
{
if (!ReferenceEquals(null, existingRelatedEntity) && !ReferenceEquals(existingRelatedEntity, item))
{
// check merge options
if (!(mergeOption == MergeOption.PreserveChanges && existingRelatedEntity.ChangeTracker.OriginalValues.ContainsKey("Address")))
{
using (entity.ChangeTrackingPrevention())
{
entity.Customers.Replace(item, existingRelatedEntity);
}
using (existingRelatedEntity.ChangeTrackingPrevention())
{
existingRelatedEntity.Address = entity;
}
}
}
}
}
}
}
if (!ReferenceEquals(null, entity.People))
{
// register relation's collection changed event if entity is new to context
if (ReferenceEquals(null, existingEntity))
{
entity.People.CollectionChanged += On_address_people_collectionChanged;
}
// attach related entities to context
if (entity.People.Count > 0)
{
foreach (var item in entity.People.ToArray())
{
var existingRelatedEntity = AttachWithRelations(item, insertMode, mergeOption, referenceTrackingList);
// update relation if entity is new to context or relation is new to entity
if (ReferenceEquals(null, existingEntity) || !existingEntity.People.Contains(item))
{
if (!ReferenceEquals(null, existingRelatedEntity) && !ReferenceEquals(existingRelatedEntity, item))
{
// check merge options
if (!(mergeOption == MergeOption.PreserveChanges && existingRelatedEntity.ChangeTracker.OriginalValues.ContainsKey("Address1")))
{
using (entity.ChangeTrackingPrevention())
{
entity.People.Replace(item, existingRelatedEntity);
}
using (existingRelatedEntity.ChangeTrackingPrevention())
{
existingRelatedEntity.Address1 = entity;
}
}
}
}
}
}
}
#endregion
#region refresh existing entity based on merge options
if (!ReferenceEquals(null, existingEntity) && !ReferenceEquals(existingEntity, entity))
{
if (Addresses.MergeOption == MergeOption.OverwriteChanges)
{
Invoke(delegate
{
existingEntity.Refresh(entity, trackChanges: false);
existingEntity.AcceptChanges();
});
}
else if (Addresses.MergeOption == MergeOption.PreserveChanges)
{
Invoke(delegate
{
existingEntity.Refresh(entity, trackChanges: false, preserveExistingChanges: true);
});
}
}
#endregion
return(existingEntity);
}