/// <summary>
/// Tries to grab from DBreeze first found node by supplied externalId
/// or returns new DGNode (not yet saved to DB) with Node.Exists = false.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="externalId"></param>
/// <param name="AsReadVisibilityScope"></param>
/// <returns></returns>
public DGNode GetNode <T>(T externalId, bool AsReadVisibilityScope = false)
{
DGNode node = null;
byte[] btExId = DataTypesConvertor.ConvertKey <T>(externalId);
if (externalId != null)
{
byte[] key = new byte[] { 1 }.Concat(btExId);
foreach (var n in tran.SelectForwardStartFrom <byte[], byte[]>(tableName, key, false, AsReadVisibilityScope))
{
if (!key.Substring(0, key.Length)._ByteArrayEquals(n.Key.Substring(0, key.Length)))
{
break;
}
else
{
node = new DGNode(btExId)
{
content = n.Value,
graph = this,
internalId = n.Key.Substring(key.Length).To_UInt32_BigEndian()
};
break;
}
}
}
return(node ?? new DGNode(btExId)
{
graph = this
});
}
/// <summary>
///
/// </summary>
/// <param name="node"></param>
/// <returns></returns>
public DGNode AddNode(DGNode node)
{
if (tran == null || node == null)
{
return(null);
}
return(AddNodes(new List <DGNode> {
node
})[0]);
}
/// <summary>
///
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="externalId"></param>
/// <param name="AsReadVisibilityScope"></param>
/// <returns></returns>
public IEnumerable <DGNode> GetParent <T>(T externalId, bool AsReadVisibilityScope = false)
{
if (this.internalId == 0) //Not existing in DB node
{
yield return(null);
}
CheckGraph();
if (externalId == null)
{
throw new Exception("Searched ID can't be null");
}
byte[] btExId = DataTypesConvertor.ConvertKey <T>(externalId);
byte[] key = new byte[] { 4 }.ConcatMany(this.internalId.To_4_bytes_array_BigEndian(), btExId);
byte[] key1 = null;
DBreeze.DataTypes.Row <byte[], byte[]> row = null;
DGNode node = null;
foreach (var n in this.graph.tran.SelectForwardStartFrom <byte[], byte[]>(this.graph.tableName, key, false, AsReadVisibilityScope))
{
//if (n.Key.Length <= 5) //1 - protocol + 4 bytes internalID
//{
// break;
//}
//else
if (!key.Substring(0, key.Length)._ByteArrayEquals(n.Key.Substring(0, key.Length)))
{
break;
}
else
{
node = new DGNode(btExId)
{
content = n.Value, graph = this.graph, internalId = n.Key.Substring(key.Length).To_UInt32_BigEndian()
};
key1 = new byte[] { 1 }.ConcatMany(btExId, node.internalId.To_4_bytes_array_BigEndian());
row = this.graph.tran.Select <byte[], byte[]>(this.graph.tableName, key1, true);
node.content = row.Value;
yield return(node);
}
}
}
/// <summary>
///
/// </summary>
/// <param name="parent">can be null</param>
/// <param name="nodes"></param>
/// <param name="id"></param>
private void AddNodesRecursive(DGNode parent, List <DGNode> nodes, ref uint id)
{
DBreeze.DataTypes.Row <byte[], byte[]> row = null;
bool newNode = false;
byte[] key = null;
foreach (var n in nodes)
{
if (n == null)
{
continue;
}
newNode = false;
//Getting new ID
if (n.internalId == 0)
{
if (id == 0)
{
row = tran.Select <byte[], byte[]>(tableName, new byte[] { 0 });
if (row.Exists)
{
id = row.Value.To_UInt32_BigEndian();
}
}
id++;
n.internalId = id;
if (n.externalId == null)
{
n.externalId = n.internalId.To_4_bytes_array_BigEndian(); //If externalID is empty it becomes uint
}
newNode = true;
}
//Instantiating Graph from node, so other operations could be done via it.
n.graph = this;
/* Binding between externalID and internalID
* 1 - node externalID (byte[]) + internalID (uint) - (binding between externalID and internalID)
* 2??? - node internalID (uint) + externalID (byte[]) - (binding between internalID and externalID)
*/
//Inserting links from parent to it
if (newNode)
{
key = new byte[] { 1 }.ConcatMany(n.externalId, n.internalId.To_4_bytes_array_BigEndian());
tran.Insert <byte[], byte[]>(tableName, key, n.content); //CONTENT
////????????????????? probably we dont need such connection
//key = new byte[] { 2 }.ConcatMany(n.internalId.To_4_bytes_array_BigEndian(), n.externalId);
//tran.Insert<byte[], byte[]>(tableName, key, null); //FOR NOW NO CONTENT
}
else
{
if (n.contentWasModified) //Saving new content
{
key = new byte[] { 1 }.ConcatMany(n.externalId, n.internalId.To_4_bytes_array_BigEndian());
tran.Insert <byte[], byte[]>(tableName, key, n.content);
}
}
if (parent != null)
{
/*
*
* Current concept
* To search kids by ExternalId from Parent
* 3 - internalID (Parent)(uint)+internalID(or better externalID(!null)+internalID) (Kid)(uint) - get all kid (referencing) nodes *-->
* To search Parent by ExternalId from Node
* 4 - internalID (Node)(uint)+(externalID+internalId)(Parent)(uint) - get all parent (referenced by) nodes *<--
*
* Alternative concept (not so good, because, gonna be very difficult to get internal via externalID - are not unique)
* To search kids by ExternalId from Parent
* 3 - internalID (Parent)(uint) + internalID(Kid)(uint) - get all kid (referencing) nodes *-->
* To search Parent by ExternalId from Node
* 4 - internalID (Node)(uint) + internalId(Parent)(uint) - get all parent (referenced by) nodes *<--
*
*/
//Filling kid of the parent node links
key = new byte[] { 3 }.ConcatMany(parent.internalId.To_4_bytes_array_BigEndian(), n.externalId, n.internalId.To_4_bytes_array_BigEndian());
//key = new byte[] { 3 }.ConcatMany(parent.internalId.To_4_bytes_array_BigEndian(), n.internalId.To_4_bytes_array_BigEndian());
tran.Insert <byte[], byte[]>(tableName, key, null);
//Filling parent of the node link
//key = new byte[] { 4 }.ConcatMany(n.internalId.To_4_bytes_array_BigEndian(), parent.externalId,parent.internalId.To_4_bytes_array_BigEndian());
//key = new byte[] { 4 }.ConcatMany(n.internalId.To_4_bytes_array_BigEndian(), parent.internalId.To_4_bytes_array_BigEndian());
//tran.Insert<byte[], byte[]>(tableName, key, null);
}
//Handling kids
if (n.LinksKids != null && n.LinksKids.Count > 0)
{
AddNodesRecursive(n, n.LinksKids, ref id);
}
}
}
