public void SaveChanges()
{
foreach (var entity in ChangedEntities.Distinct())
{
var entityType = entity.GetType();
if ((entity.State & EntityState.Added) == EntityState.Added)
{
if (entityType == typeof(Node))
{
((Node)entity).NodeId = DbControl.AllocateId(DbControl.NodePath);
}
else if (entityType == typeof(Relation))
{
((Relation)entity).RelationId = DbControl.AllocateId(DbControl.RelationPath);
}
else if (entityType == typeof(NodeProperty))
{
((NodeProperty)entity).PropertyId = DbControl.AllocateId(DbControl.NodePropertyPath);
}
else if (entityType == typeof(RelationProperty))
{
((RelationProperty)entity).PropertyId = DbControl.AllocateId(DbControl.RelationPropertyPath);
}
}
if (((entity.State & EntityState.Deleted) == EntityState.Deleted) &
((entity.State & EntityState.Added) == EntityState.Added)) continue;
if ((entity.State & EntityState.Deleted) == EntityState.Deleted)
{
if (entityType == typeof(Node))
{
var node = ((Node)entity);
DbWriter.InvalidateBlock(DbControl.NodePath, node.NodeId);
var nodeBlock = DbReader.ReadNodeBlock(node.NodeId);
var nextNodePropertyId = nodeBlock.FirstPropertyId;
while (nextNodePropertyId != 0)
{
var nextPropertyBlock =
DbReader.ReadPropertyBlock(DbControl.NodePropertyPath, nextNodePropertyId);
DbWriter.InvalidateBlock(DbControl.NodePropertyPath, nextNodePropertyId);
if (nextPropertyBlock.PropertyType is PropertyType.String)
{
DbWriter.InvalidateBlock(DbControl.StringPath,
BitConverter.ToInt32(nextPropertyBlock.Value, 0));
}
nextNodePropertyId = nextPropertyBlock.NextPropertyId;
}
var nextOutRelationId = nodeBlock.FirstOutRelationId;
while (nextOutRelationId != 0)
{
var nextOutRelationBLock = DbReader.ReadRelationBlock(nextOutRelationId);
DbWriter.InvalidateBlock(DbControl.RelationPath, nextOutRelationId);
var nextRelationPropertyId = nextOutRelationBLock.FirstPropertyId;
while (nextRelationPropertyId != 0)
{
var nextPropertyBlock = DbReader.ReadPropertyBlock(DbControl.RelationPropertyPath,
nextRelationPropertyId);
DbWriter.InvalidateBlock(DbControl.RelationPropertyPath, nextRelationPropertyId);
if (nextPropertyBlock.PropertyType is PropertyType.String)
{
DbWriter.InvalidateBlock(DbControl.StringPath,
BitConverter.ToInt32(nextPropertyBlock.Value, 0));
}
nextRelationPropertyId = nextPropertyBlock.NextPropertyId;
}
nextOutRelationId = nextOutRelationBLock.FirstNodeNextRelation;
}
var nextInRelationId = nodeBlock.FirstInRelationId;
while (nextInRelationId != 0)
{
var nextInRelationBlock = DbReader.ReadRelationBlock(nextInRelationId);
DbWriter.InvalidateBlock(DbControl.RelationPath, nextInRelationId);
var nextRelationPropertyId = nextInRelationBlock.FirstPropertyId;
while (nextRelationPropertyId != 0)
{
var nextPropertyBlock =
DbReader.ReadPropertyBlock(DbControl.RelationPropertyPath, nextRelationPropertyId);
DbWriter.InvalidateBlock(DbControl.RelationPropertyPath, nextRelationPropertyId);
if (nextPropertyBlock.PropertyType is PropertyType.String)
{
DbWriter.InvalidateBlock(DbControl.StringPath,
BitConverter.ToInt32(nextPropertyBlock.Value, 0));
}
nextRelationPropertyId = nextPropertyBlock.NextPropertyId;
}
nextInRelationId = nextInRelationBlock.SecondNodeNextRelation;
}
}
else if (entityType == typeof(Relation))
{
var relation = ((Relation)entity);
DbWriter.InvalidateBlock(DbControl.RelationPath, relation.RelationId);
var relationBlock = DbReader.ReadRelationBlock(relation.RelationId);
var nextPropertyId = relationBlock.FirstPropertyId;
while (nextPropertyId != 0)
{
var nextPropertyBlock =
DbReader.ReadPropertyBlock(DbControl.RelationPropertyPath, nextPropertyId);
DbWriter.InvalidateBlock(DbControl.NodePropertyPath, nextPropertyId);
if (nextPropertyBlock.PropertyType is PropertyType.String)
{
DbWriter.InvalidateBlock(DbControl.StringPath,
BitConverter.ToInt32(nextPropertyBlock.Value, 0));
}
nextPropertyId = nextPropertyBlock.NextPropertyId;
}
}
else if (entityType == typeof(NodeProperty))
{
var nodeProperty = ((NodeProperty)entity);
if (nodeProperty.PropertyType is PropertyType.String)
{
var nodePropertyBlock = DbReader.ReadPropertyBlock(DbControl.NodePropertyPath,
nodeProperty.PropertyId);
DbWriter.InvalidateBlock(DbControl.StringPath, BitConverter.ToInt32(nodePropertyBlock.Value, 0));
}
DbWriter.InvalidateBlock(DbControl.NodePropertyPath, nodeProperty.PropertyId);
}
else if (entityType == typeof(RelationProperty))
{
var relationProperty = ((RelationProperty)entity);
if (relationProperty.PropertyType is PropertyType.String)
{
var relationPropertyBlock = DbReader.ReadPropertyBlock(DbControl.RelationPropertyPath,
relationProperty.PropertyId);
DbWriter.InvalidateBlock(DbControl.StringPath, BitConverter.ToInt32(relationPropertyBlock.Value, 0));
}
DbWriter.InvalidateBlock(DbControl.RelationPropertyPath,
relationProperty.PropertyId);
}
else
{
throw new NotSupportedException("Not supported Entity Type");
}
continue;
}
if ((entity.State & EntityState.Added) == EntityState.Added)
{
NodeBlock nodeBlock;
RelationBlock relationBlock;
switch (entity)
{
case Node node:
nodeBlock = new NodeBlock(true, node.NodeId, 0, 0, 0, DbControl.FetchLabelId(node.Label));
DbWriter.WriteNodeBlock(nodeBlock);
break;
case Relation relation:
//Cast, Create with given information
relationBlock = new RelationBlock
{
Used = true,
FirstNodeId = relation.From.NodeId,
SecondNodeId = relation.To.NodeId,
FirstNodePreviousRelationId = 0,
SecondNodePreviousRelationId = 0,
LabelId = DbControl.FetchLabelId(relation.Label),
FirstPropertyId = 0,
RelationId = relation.RelationId
};
// Read Source, Target nodes to change the links in them and get their current links
var fromNodeBlock = DbReader.ReadNodeBlock(relationBlock.FirstNodeId);
var toNodeBlock = DbReader.ReadNodeBlock(relationBlock.SecondNodeId);
// Point to the current relations
relationBlock.FirstNodeNextRelation = fromNodeBlock.FirstOutRelationId;
relationBlock.SecondNodeNextRelation = toNodeBlock.FirstInRelationId;
// Read Relations to which nodes point to update them
if (fromNodeBlock.FirstOutRelationId != 0)
{
var fromNodeFirstOutRelationBlock =
DbReader.ReadRelationBlock(fromNodeBlock.FirstOutRelationId);
fromNodeFirstOutRelationBlock.FirstNodePreviousRelationId = relation.RelationId;
DbWriter.WriteRelationBlock(fromNodeFirstOutRelationBlock);
}
if (toNodeBlock.FirstInRelationId != 0)
{
var toNodeFirstInRelationBlock =
DbReader.ReadRelationBlock(toNodeBlock.FirstInRelationId);
toNodeFirstInRelationBlock.SecondNodePreviousRelationId = relation.RelationId;
DbWriter.WriteRelationBlock(toNodeFirstInRelationBlock);
}
toNodeBlock.FirstInRelationId = relation.RelationId;
fromNodeBlock.FirstOutRelationId = relation.RelationId;
DbWriter.WriteNodeBlock(toNodeBlock);
DbWriter.WriteNodeBlock(fromNodeBlock);
DbWriter.WriteRelationBlock(relationBlock);
break;
case NodeProperty _:
case RelationProperty _:
var property = (Property)entity;
byte[] byteValue = new byte[4];
switch (property.PropertyType)
{
case PropertyType.Int:
byteValue = BitConverter.GetBytes((int)property.Value);
break;
case PropertyType.Bool:
byteValue[3] = (byte)((bool)property.Value ? 1 : 0);
break;
case PropertyType.Float:
byteValue = BitConverter.GetBytes((float)property.Value);
break;
case PropertyType.String:
// Add to String Storage, get returned pointer to the string storage, write it as the byteValue
var newStringId = DbControl.AllocateId(DbControl.StringPath);
DbWriter.WriteStringBlock(new StringBlock(true, (string)property.Value,
newStringId));
byteValue = BitConverter.GetBytes(newStringId);
break;
default:
throw new NotSupportedException();
}
int parentId;
PropertyBlock propertyBlock;
switch (property)
{
case NodeProperty _:
parentId = ((Node)property.Parent).NodeId;
propertyBlock = new NodePropertyBlock(property.PropertyId, true,
property.PropertyType,
DbControl.FetchPropertyNameId(property.Key),
byteValue, 0, parentId);
nodeBlock = DbReader.ReadNodeBlock(parentId);
propertyBlock.NextPropertyId = nodeBlock.FirstPropertyId;
nodeBlock.FirstPropertyId = propertyBlock.PropertyId;
DbWriter.WritePropertyBlock(propertyBlock);
DbWriter.WriteNodeBlock(nodeBlock);
break;
case RelationProperty _:
parentId = ((Relation)property.Parent).RelationId;
propertyBlock = new RelationPropertyBlock(property.PropertyId, true,
property.PropertyType,
DbControl.FetchPropertyNameId(property.Key),
byteValue, 0, parentId);
relationBlock = DbReader.ReadRelationBlock(parentId);
propertyBlock.NextPropertyId = relationBlock.FirstPropertyId;
relationBlock.FirstPropertyId = propertyBlock.PropertyId;
DbWriter.WritePropertyBlock(propertyBlock);
DbWriter.WriteRelationBlock(relationBlock);
break;
default:
throw new NotSupportedException();
}
break;
}
continue;
}
if ((entity.State & EntityState.Modified) == EntityState.Modified)
{
switch (entity)
{
case Node _:
throw new NotSupportedException(
"Node modification is not supported. Update it's properties instead.");
case Relation _:
throw new NotSupportedException(
"Relation modification is not supported. Update it's properties instead.");
case NodeProperty _: //
case RelationProperty _:
var property = (Property)entity;
var propertyPath = (property is NodeProperty)
? DbControl.NodePropertyPath
: DbControl.RelationPropertyPath;
var oldPropertyBlock = DbReader.ReadPropertyBlock(propertyPath, property.PropertyId);
byte[] byteValue = new byte[4];
switch (property.PropertyType)
{
case PropertyType.Int:
byteValue = BitConverter.GetBytes((int)property.Value);
break;
case PropertyType.Bool:
byteValue[3] = (byte)((bool)property.Value ? 1 : 0);
break;
case PropertyType.Float:
byteValue = BitConverter.GetBytes((float)property.Value);
break;
case PropertyType.String:
DbWriter.InvalidateBlock(DbControl.StringPath,
BitConverter.ToInt32(oldPropertyBlock.Value, 0));
var newStringId = DbControl.AllocateId(DbControl.StringPath);
DbWriter.WriteStringBlock(new StringBlock(true, (string)property.Value,
newStringId));
byteValue = BitConverter.GetBytes(newStringId);
break;
default:
throw new NotSupportedException("Such Property dtye is not supported");
}
oldPropertyBlock.Value = byteValue;
DbWriter.WritePropertyBlock(oldPropertyBlock);
break;
}
}
}
ChangedEntities.Clear();
}