/// <summary>
/// Gets or sets the <see cref="ServerObject">ServerObject</see> that is a Parent object.
/// </summary>
/// <remarks>
/// On object access if a parent exists but has not be retrieved by ObjectServer then it will be retrieved and returned.
/// Otherwise the existing object will be returned. If you wish a null value to be set the assign null to the parent.
/// When an object is assigned as a parent, ObjectServer will locate the correct children collection and automatically append the current object.
/// </remarks>
/// <param name="key">The name of the property in the <see cref="ServerObject">ServerObject</see> which exposes this Parent.</param>
/// <value>A <see cref="ServerObject">ServerObject</see> that is a Parent object or if no parent exists null.</value>
public ServerObject this[string key]
{
get
{
if (data[key] == null)
{
Trace.WriteLineIf(DebugOutput.Enabled, "Parent not found, loading");
TypeSchema schema = SchemaCache.Current.GetSchema(obj.ServerObjectType);
ParentSchema parentSchema = schema.FindParentSchema(key);
ServerObject parent = obj.Transaction.Select(parentSchema.Property.PropertyType, obj.Data.GetValue(key));
data[key] = parent;
return(parent);
}
else if (Convert.IsDBNull(data[key]))
{
Trace.WriteLineIf(DebugOutput.Enabled, "Key Value is DBNull.Value returning null");
return(null);
}
return(data[key] as ServerObject);
}
set
{
if (value == null)
{
Trace.WriteLineIf(DebugOutput.Enabled, "Parent set to null, setting key value to DBNull.Value");
obj.Data.SetValue(key, DBNull.Value);
data[key] = DBNull.Value;
UpdateState(key);
}
else
{
if (!value.Equals(data[key]))
{
Trace.WriteLineIf(DebugOutput.Enabled, "New Parent set");
ServerObject newParent = value as ServerObject;
ServerObject oldParent = data[key] != null ? data[key] as ServerObject : null;
TypeSchema schema = SchemaCache.Current.GetSchema(newParent.ServerObjectType);
object parentKey = newParent.Data.GetValue(schema.PrimaryKey.Property.Name);
obj.Data.SetValue(key, parentKey);
data[key] = newParent;
UpdateState(key);
foreach (ChildrenSchema childSchema in schema.ChildrenSchemas)
{
if (childSchema.PropertyName == key && childSchema.ChildType == obj.ServerObjectType)
{
if (oldParent != null)
{
Trace.WriteLineIf(DebugOutput.Enabled, "Removing from children collection " + childSchema.Property.Name);
ServerObjectCollection oldChildren = oldParent.Children.GetValue(childSchema.Property.Name);
if (oldChildren != null && oldChildren.Contains(obj))
{
oldChildren.Remove(obj);
}
}
Trace.WriteLineIf(DebugOutput.Enabled, "Adding to children collection " + childSchema.Property.Name);
ServerObjectCollection newChildren = newParent.Children.GetValue(childSchema.Property.Name);
if (newChildren != null && !newChildren.Contains(obj))
{
newChildren.Add(obj);
}
break;
}
}
}
}
}
}
internal ServerObjectCollection SelectChildren(ServerObject obj, string propertyName)
{
Trace.WriteLineIf(DebugOutput.Enabled, "Selecting children for " + propertyName);
TypeSchema schema = SchemaCache.Current.GetSchema(obj.ServerObjectType);
ChildrenSchema childrenSchema = schema.FindChildrenSchema(propertyName);
ServerObjectCollection children = null;
object primaryKey = obj.Data.GetValue(schema.PrimaryKey.Property.Name);
Query query = new Query(new Condition(childrenSchema.PropertyName, Expression.Equal, primaryKey));
children = Select(childrenSchema.ChildType, query);
Trace.WriteLineIf(DebugOutput.Enabled, "Checking cache for more items");
foreach (ServerObject cacheItem in objectCache.GetCacheItem(childrenSchema.ChildType))
{
if (primaryKey.Equals(cacheItem.Data.GetValue(childrenSchema.PropertyName)) && !children.Contains(cacheItem))
{
children.Add(cacheItem);
}
}
ServerObjectCollection toRemove = new ServerObjectCollection();
foreach (ServerObject child in children)
{
if (!primaryKey.Equals(child.Data.GetValue(childrenSchema.PropertyName)))
{
toRemove.Add(child);
}
}
foreach (ServerObject child in toRemove)
{
children.Remove(child);
}
return(children);
}
