/// <summary>
/// Replaces a node.
/// </summary>
/// <param name="operation">Details of the operation performed.</param>
public virtual void Replace(IWriteableReplaceOperation operation)
{
int BlockIndex = operation.BlockIndex;
Debug.Assert(BlockIndex >= 0 && BlockIndex < BlockStateList.Count);
IWriteableBlockState BlockState = (IWriteableBlockState)BlockStateList[BlockIndex];
int Index = operation.Index;
Debug.Assert(Index >= 0 && Index < BlockState.StateList.Count);
IBlock ChildBlock = BlockState.ChildBlock;
Node ParentNode = Owner.Node;
IWriteableNodeState OldChildState = (IWriteableNodeState)BlockState.StateList[Index];
Node OldNode = OldChildState.Node;
IWriteableBrowsingBlockNodeIndex OldBrowsingIndex = (IWriteableBrowsingBlockNodeIndex)OldChildState.ParentIndex;
BlockState.Remove(OldBrowsingIndex, Index);
NodeTreeHelperBlockList.ReplaceInBlock(ChildBlock, Index, operation.NewNode);
IWriteableBrowsingExistingBlockNodeIndex NewBrowsingIndex = CreateBrowsingNodeIndex(operation.NewNode, BlockIndex, Index);
IWriteablePlaceholderNodeState NewChildState = (IWriteablePlaceholderNodeState)CreateNodeState(NewBrowsingIndex);
BlockState.Insert(NewBrowsingIndex, Index, NewChildState);
operation.Update(OldBrowsingIndex, NewBrowsingIndex, OldNode, NewChildState);
}