public void DeleteNode(int expectedIndex, int nodeToLeftIndex)
{
if (expectedIndex != currentIndex)
{
throw new InvalidOperationException();
}
pruningCursor.DeleteNode();
currentIndex = nodeToLeftIndex;
Debug.Assert(pruningCursor.ReadNode().Index == nodeToLeftIndex);
}
public static void PruneNode <T>(IMerkleTreePruningCursor <T> cursor, int index)
where T : IMerkleTreeNode <T>
{
if (!cursor.TryMoveToIndex(index))
{
return;
}
var node = cursor.ReadNode();
if (node.Depth != 0)
{
return;
}
if (!node.Pruned)
{
node = node.AsPruned();
cursor.WriteNode(node);
}
bool didWork;
do
{
didWork = false;
if (node.IsLeft())
{
if (cursor.TryMoveRight())
{
var rightNode = cursor.ReadNode();
if (node.Pruned && rightNode.Pruned && node.Depth == rightNode.Depth)
{
var newNode = node.PairWith(rightNode);
cursor.DeleteNode();
//TODO cursor.MoveLeft();
cursor.WriteNode(newNode);
node = newNode;
didWork = true;
}
}
else
{
if (node.Index != 0 && node.Pruned)
{
var newNode = node.PairWithSelf();
//cursor.MoveLeft();
cursor.WriteNode(newNode);
node = newNode;
didWork = true;
}
}
}
else
{
if (cursor.TryMoveLeft())
{
var leftNode = cursor.ReadNode();
if (node.Pruned && leftNode.Pruned && node.Depth == leftNode.Depth)
{
var newNode = leftNode.PairWith(node);
cursor.WriteNode(newNode);
cursor.MoveRight();
cursor.DeleteNode();
//TODO cursor.MoveLeft();
node = newNode;
didWork = true;
}
}
}
}while (didWork);
}