/// <summary>
/// Copy changed values
/// </summary>
protected virtual IList <EntityTuple <TEntity> > ReduceToModifications <TEntity>(IList <TEntity> source) where TEntity : Entity
{
var entities = new List <EntityTuple <TEntity> >();
foreach (var entity in source)
{
var reducedEntity = ReduceToModifications(entity);
var tuple = new EntityTuple <TEntity>(entity, reducedEntity);
entities.Add(tuple);
}
return(entities);
}
/// <summary>
/// Modifies the EntityTuple.ReducedEntity by replacing related entities with their corresponding clones from the reduced entity set
/// </summary>
/// <param name="entityTuple"></param>
/// <param name="flatTransmissionSet"></param>
protected virtual void FixupRelations(EntityTuple <Entity> entityTuple, IEnumerable <EntityTuple <Entity> > flatTransmissionSet)
{
Entity entity = entityTuple.Entity;
Entity reducedEntity = entityTuple.ReducedEntity;
switch (reducedEntity.ChangeTracker.State)
{
case ObjectState.Added:
{
// copy navigation properties
var navigationProperties = entity.PropertyInfos
.Where(p => p.IsPhysical && p.Attributes.Any(attribute => attribute is NavigationPropertyAttribute))
.Select(p => p.PropertyInfo);
foreach (var navigationProperty in navigationProperties)
{
var referencedInstance = navigationProperty.GetValue(entity, null);
var referencedEntityCollection = referencedInstance as ITrackableCollection;
if (!ReferenceEquals(null, referencedEntityCollection))
{
if (referencedEntityCollection.Count > 0)
{
var collection = navigationProperty.GetValue(reducedEntity, null) as ITrackableCollection;
foreach (Entity referencedEntity in referencedEntityCollection)
{
// lookup reduced version of current value (entity)
Entity changeSetEntity;
var entry = flatTransmissionSet.FirstOrDefault(e => e.Entity.Equals(referencedEntity));
if (entry != null)
{
changeSetEntity = entry.ReducedEntity;
}
else
{
// in case of directed relation (i.e. only one entity has a relation to the other and the other entity has not relation back)
// the related entity might not yet be in the change set and has to be specifically created
changeSetEntity = ReduceToModifications(referencedEntity);
}
collection.Add(changeSetEntity);
}
}
}
else if (referencedInstance is Entity)
{
// lookup reduced version of current value (entity)
var entry = flatTransmissionSet.FirstOrDefault(e => e.Entity.Equals(referencedInstance));
if (entry != null)
{
navigationProperty.SetValue(reducedEntity, entry.ReducedEntity, null);
}
}
}
}
break;
case ObjectState.Unchanged:
if (entity.HasChanges)
{
// there are changes in relations
goto case ObjectState.Modified;
}
break;
case ObjectState.Modified:
case ObjectState.Deleted:
{
// copy changed navigation properties (relations and foreign keys)
// single relation
var physicalProperties = entity.PropertyInfos.Where(p => p.IsPhysical && p.Attributes.Any(attribute => attribute is NavigationPropertyAttribute)).ToDictionary(p => p.Name);
foreach (var property in entity.ChangeTracker.OriginalValues.Where(p => physicalProperties.ContainsKey(p.Key)))
{
if (!reducedEntity.ChangeTracker.OriginalValues.ContainsKey(property.Key))
{
// lookup reduced version of current value (entity)
Entity currentChangeSetEntity = null;
{
// get current value (entity)
var currentEntity = (Entity)entity.GetProperty(property.Key, true);
if (currentEntity != null)
{
var entry = flatTransmissionSet.FirstOrDefault(e => e.Entity.Equals(currentEntity));
if (entry != null)
{
currentChangeSetEntity = entry.ReducedEntity;
}
else
{
// in case of directed relation (i.e. only one entity has a relation to the other and the other entity has not relation back)
// the related entity might not yet be in the change set and has to be specifically created
currentChangeSetEntity = ReduceToModifications(currentEntity);
}
}
}
Entity originalChangeSetEntity = null;
{
// get current value (entity)
var currentEntity = (Entity)entity.ChangeTracker.OriginalValues[property.Key];
if (currentEntity != null)
{
var entry = flatTransmissionSet.FirstOrDefault(e => e.Entity.Equals(currentEntity));
if (entry != null)
{
originalChangeSetEntity = entry.ReducedEntity;
}
else
{
// in case of directed relation (i.e. only one entity has a relation to the other and the other entity has not relation back)
// the related entity might not yet be in the change set and has to be specifically created
originalChangeSetEntity = ReduceToModifications(currentEntity);
}
}
}
reducedEntity.SetProperty(property.Key, currentChangeSetEntity, true);
reducedEntity.ChangeTracker.OriginalValues[property.Key] = originalChangeSetEntity;
}
}
// relation added to collection
foreach (var relation in entity.ChangeTracker.ObjectsAddedToCollectionProperties)
{
var navigationProperty = reducedEntity.GetType().GetProperty(relation.Key).GetValue(reducedEntity, null) as ITrackableCollection;
var objectList = new EntityList();
foreach (var referencedEntity in relation.Value)
{
// lookup reduced version of current value (entity)
Entity changeSetEntity;
var entry = flatTransmissionSet.FirstOrDefault(e => e.Entity.Equals(referencedEntity));
if (entry != null)
{
changeSetEntity = entry.ReducedEntity;
}
else
{
// in case of directed relation (i.e. only one entity has a relation to the other and the other entity has not relation back)
// the related entity might not yet be in the change set and has to be specifically created
changeSetEntity = ReduceToModifications(referencedEntity);
}
if (changeSetEntity != null && !navigationProperty.Contains(changeSetEntity))
{
navigationProperty.Add(changeSetEntity);
objectList.Add(changeSetEntity);
}
}
if (reducedEntity.ChangeTracker.ObjectsAddedToCollectionProperties.ContainsKey(relation.Key))
{
continue;
}
reducedEntity.ChangeTracker.ObjectsAddedToCollectionProperties.Add(relation.Key, objectList);
}
// relation removed from collection
foreach (var relation in entity.ChangeTracker.ObjectsRemovedFromCollectionProperties)
{
var objectList = new EntityList();
foreach (var referencedEntity in relation.Value)
{
// lookup reduced version of current value (entity)
Entity changeSetEntity;
var entry = flatTransmissionSet.FirstOrDefault(e => e.Entity.Equals(referencedEntity));
if (entry != null)
{
changeSetEntity = entry.ReducedEntity;
}
else
{
// in case of directed relation (i.e. only one entity has a relation to the other and the other entity has no relation back)
// the related entity might not yet be in the change set and has to be specifically created
changeSetEntity = ReduceToModifications(referencedEntity);
}
if (changeSetEntity != null)
{
objectList.Add(changeSetEntity);
}
}
reducedEntity.ChangeTracker.ObjectsRemovedFromCollectionProperties.Add(relation.Key, objectList);
}
}
break;
default:
throw new InvalidOperationException();
}
}