/// <summary>Inserts a list of items at the specified index. This method
/// may not insert all items at once, so there is a sourceIndex parameter
/// which points to the next item to be inserted. When sourceIndex reaches
/// source.Count, the insertion is complete.</summary>
/// <param name="index">The index at which to insert the contents of
/// source. Important: if sourceIndex > 0, insertion of the remaining
/// items starts at [index + sourceIndex].</param>
/// <returns>Returns non-null if the node is split, as explained
/// in the documentation of <see cref="Insert"/>.</returns>
/// <remarks>This method can only be called for ALists, since other tree
/// types don't allow insertion at a specific index.</remarks>
/// <exception cref="NotSupportedException">This node does not allow insertion at an arbitrary location (e.g. BList node).</exception>
public virtual AListNode <K, T> InsertRange(uint index, IListSource <T> source, ref int sourceIndex, out AListNode <K, T> splitRight, IAListTreeObserver <K, T> tob)
{
throw new NotSupportedException();
}
/// <summary>Takes an element from a left sibling.</summary> /// <returns>Returns the number of elements moved on success (1 if a leaf /// node, TotalCount of the child moved otherwise), or 0 if either (1) /// IsFullLeaf is true, or (2) one or both nodes is frozen.</returns> internal abstract uint TakeFromLeft(AListNode <K, T> leftSibling, IAListTreeObserver <K, T> tob);
/// <summary>Inserts an item at the specified index. This method can only
/// be called for ALists, since other tree types don't allow insertion at
/// a specific index.</summary>
/// <returns>Returns null if the insert completed normally. If the node
/// split in half, the return value is the left side, and splitRight is
/// set to the right side.</returns>
/// <exception cref="NotSupportedException">This node does not allow insertion at an arbitrary location (e.g. BList node).</exception>
public virtual AListNode <K, T> Insert(uint index, T item, out AListNode <K, T> splitRight, IAListTreeObserver <K, T> tob)
{
throw new NotSupportedException();
}
/// <summary>Performs an insert or replace operation in a <see cref="SparseAList{T}"/>.</summary>
/// <param name="op">Describes the operation to be performed</param>
/// <param name="index">Relative index in child node where the sparse
/// operation began; <c>index + op.SourceIndex</c> is where the next
/// insertion or replacement must occur. For example if the child
/// node represents items 100-200, and op.SourceIndex is 7, and
/// the absolute index of the start of the operation (op.AbsoluteIndex)
/// is 98, then <c>index</c> will be -2 (98-100) and the next insertion
/// or replacement will occur at index 5 in the child. <c>index</c> may
/// be negative but <c>index + op.SourceIndex >= 0</c>.</param>
/// <param name="splitLeft">If the node needs to split, splitLeft and
/// splitRight are set to the new pieces. If the node is undersized,
/// splitLeft is set to <c>this</c> (the called node) and splitRight
/// is set to null.</param>
/// <returns>Size change (always 0 for a replacement operation)</returns>
/// <remarks>In a language with templates, I would change a couple
/// of elements of <see cref="AListSparseOperation{T}"/> into
/// template parameters.</remarks>
internal virtual int DoSparseOperation(ref AListSparseOperation <T> op, int index, out AListNode <K, T> splitLeft, out AListNode <K, T> splitRight)
{
throw new NotSupportedException();
}
/// <summary>Takes an element from a right sibling.</summary> /// <returns>Returns the number of elements moved on success (1 if a leaf /// node, TotalCount of the child moved otherwise), or 0 if either (1) /// IsFullLeaf is true, or (2) one or both nodes is frozen.</returns> internal abstract uint TakeFromRight(AListNode <K, T> rightSibling, IAListTreeObserver <K, T> tob);
internal override int DoSparseOperation(ref AListSparseOperation <T> op, int index, out AListNode <int, T> splitLeft, out AListNode <int, T> splitRight)
{
Debug.Assert(!IsFrozen);
if (op.IsInsert)
{
return(DoInsert(ref op, index, out splitLeft, out splitRight));
}
else
{
return(DoReplace(ref op, index, out splitLeft, out splitRight));
}
}
/// <summary>Performs a retrieve, add, remove or replace operation on a
/// single item in an organized A-list (such as a BList or BDictionary).</summary>
/// <param name="op">An object that describes the operation to be performed
/// and the parameters of the tree (comparers and observers).</param>
/// <param name="splitLeft">null if the operation completed normally. If an
/// item was added and the node split, splitLeft and splitRight are new
/// nodes that each contain roughly half of the items from this node.
/// <para/>
/// If an item was removed and the node became undersized, splitLeft is set
/// to this (the node itself) and splitRight is set to null. Likewise, if
/// the aggregate value of the node changed (in a B+tree, this means that
/// the highest key changed) then splitLeft is set to the node itself and
/// splitRight is set to null.
/// </param>
/// <returns>Returns 1 if a new item was added, -1 if an item was removed,
/// or 0 if the number of items in the tree did not change.</returns>
/// <exception cref="NotSupportedException">This node does not belong to an
/// organized tree (e.g. normal AList).</exception>
/// <exception cref="KeyAlreadyExistsException">The key op.NewKey already
/// existed in the tree and op.Mode was
/// <see cref="AListOperation"/>.AddOrThrow.</exception>
/// <remarks>
/// If op.Mode is <see cref="AListOperation"/>.ReplaceIfPresent, this method
/// informs the caller when replacement occurs in this mode by changing
/// op.Mode to AddDuplicateMode.ReplaceExisting.
/// </remarks>
internal virtual int DoSingleOperation(ref AListSingleOperation <K, T> op, out AListNode <K, T> splitLeft, out AListNode <K, T> splitRight)
{
throw new NotSupportedException();
}
public BDictionaryInner(AListNode <K, KeyValuePair <K, V> > left, AListNode <K, KeyValuePair <K, V> > right, int maxNodeSize) : base(left, right, maxNodeSize)
{
}
protected override AListInnerBase <K, KeyValuePair <K, V> > SplitAt(int divAt, out AListNode <K, KeyValuePair <K, V> > right)
{
right = new BDictionaryInner <K, V>(this, divAt, LocalCount - divAt, _children[divAt].Index, MaxNodeSize);
return(new BDictionaryInner <K, V>(this, 0, divAt, 0, MaxNodeSize));
}
public BListInner(AListNode <K, T> left, AListNode <K, T> right, int maxNodeSize)
: base(left, right, maxNodeSize)
{
_highestKey = new K[_children.Length - 1];
_highestKey[0] = GetHighestKey(left);
}
protected new AListInnerBase <K, T> HandleChildSplit(int i, AListNode <K, T> splitLeft, ref AListNode <K, T> splitRight, IAListTreeObserver <K, T> tob)
{
// Update _highestKey. base.HandleChildSplit will call LLInsert
// which will update _highestKey for the newly inserted right child,
// but we must manually update the left child at _highestKey[i],
// unless i == _childCount-1.
if (i < _childCount - 1)
{
_highestKey[i] = GetHighestKey(splitLeft);
}
return(base.HandleChildSplit(i, splitLeft, ref splitRight, tob));
}
internal override int DoSingleOperation(ref AListSingleOperation <K, T> op, out AListNode <K, T> splitLeft, out AListNode <K, T> splitRight)
{
Debug.Assert(!IsFrozen || op.Mode == AListOperation.Retrieve);
AssertValid();
var tob = GetObserver(op.List);
int i = BinarySearchK(op.Key, op.CompareKeys);
if (op.Mode != AListOperation.Retrieve)
{
AutoClone(ref _children[i].Node, this, tob);
if (op.Mode >= AListOperation.Add && _children[i].Node.IsFullLeaf)
{
TryToShiftAnItemToSiblingOfLeaf(i, tob);
// Binary search result might now be off-by-1
i = BinarySearchK(op.Key, op.CompareKeys);
}
}
AssertValid();
op.BaseIndex += _children[i].Index;
int sizeChange = _children[i].Node.DoSingleOperation(ref op, out splitLeft, out splitRight);
if (sizeChange != 0)
{
AdjustIndexesAfter(i, sizeChange);
}
// Handle child split / undersized / highest key changed
if (splitLeft != null)
{
if (splitRight != null)
{
splitLeft = HandleChildSplit(i, splitLeft, ref splitRight, tob);
}
else
{
// Node is undersized and/or highest key changed
bool flagParent = false;
if (op.AggregateChanged != 0)
{
if (i < _childCount - 1)
{
_highestKey[i] = op.AggregateKey;
op.AggregateChanged = 0;
}
else
{
// Update highest key in parent node instead
flagParent = true;
}
}
if (splitLeft.IsUndersized)
{
flagParent |= HandleUndersized(i, tob);
}
if (flagParent)
{
splitLeft = this;
}
else
{
splitLeft = null;
}
}
}
AssertValid();
return(sizeChange);
}
private int DoInsert(ref AListSparseOperation <T> op, int index0, out AListNode <int, T> splitLeft, out AListNode <int, T> splitRight)
{
Debug.Assert(_totalCount + op.SourceCount >= _totalCount); // caller ensures list size does not overflow
if (op.WriteEmpty)
{
// SourceIndex will be 0 because inserting empty space always finishes on the first try.
Debug.Assert(op.SourceIndex == 0);
InsertSpace((uint)index0, op.SourceCount);
op.SourceIndex = op.SourceCount;
splitLeft = splitRight = null;
return(op.SourceCount);
}
uint index = (uint)(index0 + op.SourceIndex);
int i;
BinarySearch(index, out i);
int leftHere = _maxNodeSize - _list.Count;
if (leftHere == 0)
{
SplitLeaf(out splitLeft, out splitRight, i == _list.Count);
return(0); // return without inserting anything
}
if (op.Source == null)
{
// Special case: insert a single item
Debug.Assert(op.SourceCount == 1);
_list.AutoRaiseCapacity(1, _maxNodeSize);
_list.Insert(i, new Entry(index, op.Item));
AdjustOffsetsStartingAt(i + 1, ref _list, 1);
_totalCount++;
op.SourceIndex++;
splitLeft = splitRight = null;
return(1);
}
splitLeft = splitRight = null;
if (op.SparseSource != null)
{
var source = op.SparseSource;
var tempList = new InternalList <Entry>(leftHere);
int?si;
T item;
for (int prev = op.SourceIndex - 1; ; prev = si.Value)
{
si = prev;
item = source.NextHigherItem(ref si);
if (si == null)
{
break;
}
tempList.Add(new Entry {
Offset = (uint)(index0 + si.Value),
Item = item
});
if (tempList.Count == leftHere)
{
break;
}
}
_list.InsertRangeHelper(i, tempList.Count);
for (int j = 0; j < tempList.Count; j++)
{
_list[i + j] = tempList[j];
}
int newSourceIndex = si == null ? source.Count : si.Value + 1;
int virtualItemsInserted = newSourceIndex - op.SourceIndex;
op.SourceIndex = newSourceIndex;
AdjustOffsetsStartingAt(i + tempList.Count, ref _list, virtualItemsInserted);
_totalCount += (uint)virtualItemsInserted;
return(virtualItemsInserted);
}
else
{
int c = op.SourceCount;
int leftToInsert = c - op.SourceIndex;
Debug.Assert(leftToInsert > 0);
int amtToIns = System.Math.Min(leftHere, leftToInsert);
_list.AutoRaiseCapacity(amtToIns, _maxNodeSize);
_list.InsertRangeHelper(i, amtToIns);
for (int j = 0; j < amtToIns; j++)
{
_list[i + j] = new Entry(index + (uint)j, op.Source[op.SourceIndex + j]);
}
AdjustOffsetsStartingAt(i + amtToIns, ref _list, amtToIns);
_totalCount += (uint)amtToIns;
op.SourceIndex += amtToIns;
//if (tob != null) tob.AddingItems(slice, this, false);
return(amtToIns);
}
}
private int DoReplace(ref AListSparseOperation <T> op, int index, out AListNode <int, T> splitLeft, out AListNode <int, T> splitRight)
{
if (op.WriteEmpty)
{
int i1, i2;
uint leftToReplace = (uint)(op.SourceCount - op.SourceIndex);
uint startAt = (uint)(index + op.SourceIndex);
i1 = GetSectionRange(startAt, leftToReplace, out i2);
_list.RemoveRange(i1, i2 - i1);
uint amtReplaced = System.Math.Min(leftToReplace, _totalCount - startAt);
op.SourceIndex += (int)amtReplaced;
splitLeft = splitRight = null;
if (IsUndersized)
{
splitLeft = this;
}
return(0);
}
// Currently there is only one other replacement operation exposed on
// SparseAList, namely changing the value of a single item. I'll
// include code for changing multiple items at once, but not optimize
// that case. And no sparse support.
Debug.Assert(op.SparseSource == null);
splitLeft = splitRight = null;
if (op.Source != null)
{
for (; op.SourceIndex < op.SourceCount; op.SourceIndex++)
{
op.Item = op.Source[op.SourceIndex];
if (!ReplaceSingleItem(ref op, (uint)(index + op.SourceIndex)))
{
SplitLeaf(out splitLeft, out splitRight, false);
return(0);
}
}
}
else
{
Debug.Assert(op.SourceIndex == 0 && op.SourceCount == 1);
if (!ReplaceSingleItem(ref op, (uint)(index + op.SourceIndex)))
{
SplitLeaf(out splitLeft, out splitRight, false);
return(0);
}
op.SourceIndex++;
}
return(0);
}
/// <summary>Called by DoSingleOperation to split a full node, then retry the add operation.</summary>
/// <remarks>Same arguments and return value as DoSingleOperation.</remarks>
internal virtual int SplitAndAdd(ref AListSingleOperation <K, T> op, out AListNode <K, T> splitLeft, out AListNode <K, T> splitRight)
{
// Tell DoSingleOperation not to send notifications to the observer
op.AggregateChanged |= 2;
int divAt = _list.Count >> 1;
var mid = _list[divAt];
var left = new BListLeaf <K, T>(_maxNodeSize, _list.CopySection(0, divAt));
var right = new BListLeaf <K, T>(_maxNodeSize, _list.CopySection(divAt, _list.Count - divAt));
int sizeChange;
if (op.CompareToKey(mid, op.Key) >= 0)
{
sizeChange = left.DoSingleOperation(ref op, out splitLeft, out splitRight);
}
else
{
op.BaseIndex += left.TotalCount;
sizeChange = right.DoSingleOperation(ref op, out splitLeft, out splitRight);
}
op.AggregateChanged &= unchecked ((byte)~2);
// (splitLeft may be non-null, meaning that the highest key changed, which doesn't matter here.)
Debug.Assert(splitRight == null);
Debug.Assert(sizeChange == 1);
splitLeft = left;
splitRight = right;
return(sizeChange);
}
protected K GetHighestKey(AListNode <K, T> node)
{
return(GetKey(node.GetLastItem()));
}
internal override int DoSingleOperation(ref AListSingleOperation <K, T> op, out AListNode <K, T> splitLeft, out AListNode <K, T> splitRight)
{
T searchItem = op.Item;
int index = _list.BinarySearch(op.Key, op.CompareToKey, op.LowerBound);
if (op.Found = (index >= 0))
{
op.Item = _list[index]; // save old value
if (op.RequireExactMatch && (searchItem == null ? op.Item == null : !searchItem.Equals(op.Item)))
{
op.Found = false;
}
}
else
{
index = ~index;
}
splitLeft = splitRight = null;
op.BaseIndex += (uint)index;
if (op.Mode == AListOperation.Retrieve)
{
return(0);
}
if (op.Mode >= AListOperation.Add)
{
// Possible operations: Add, AddOrReplace, AddIfNotPresent, AddOrThrow
if (_list.Count >= _maxNodeSize && (op.Mode == AListOperation.Add || !op.Found))
{
op.BaseIndex -= (uint)index;
op.Item = searchItem;
return(SplitAndAdd(ref op, out splitLeft, out splitRight));
}
if (op.Found && op.Mode != AListOperation.Add)
{
if (op.Mode == AListOperation.AddOrThrow)
{
throw new KeyAlreadyExistsException();
}
else if (op.Mode == AListOperation.AddIfNotPresent)
{
return(0);
}
}
else // add new item
{
if (HasListChanging(op.List))
{
CallListChanging(op.List, new ListChangeInfo <T>(NotifyCollectionChangedAction.Add, (int)op.BaseIndex, 1, ListExt.Single(searchItem)));
}
if (index == _list.Count)
{ // Highest key may change
splitLeft = this;
op.AggregateChanged |= 1;
op.AggregateKey = op.List.GetKey(searchItem);
}
_list.AutoRaiseCapacity(1, _maxNodeSize);
_list.Insert(index, searchItem);
if (GetObserver(op.List) != null)
{
if ((op.AggregateChanged & 2) == 0)
{
GetObserver(op.List).ItemAdded(searchItem, this);
}
}
return(1);
}
Debug.Assert(op.Mode == AListOperation.AddOrReplace);
}
else if (op.Found)
{
// Possible operations: ReplaceIfPresent, Remove
if (op.Mode == AListOperation.Remove)
{
if (HasListChanging(op.List))
{
CallListChanging(op.List, new ListChangeInfo <T>(NotifyCollectionChangedAction.Remove, (int)op.BaseIndex, -1, null));
}
_list.RemoveAt(index);
if (index == _list.Count)
{ // Highest key may change
splitLeft = this;
if (_list.Count != 0)
{
op.AggregateChanged |= 1;
op.AggregateKey = op.List.GetKey(_list.Last);
}
}
else if (IsUndersized)
{
splitLeft = this;
}
if (GetObserver(op.List) != null)
{
Debug.Assert((op.AggregateChanged & 2) == 0);
GetObserver(op.List).ItemRemoved(op.Item, this);
}
return(-1);
}
Debug.Assert(op.Mode == AListOperation.ReplaceIfPresent);
}
else
{
Debug.Assert(op.Mode == AListOperation.Remove || op.Mode == AListOperation.ReplaceIfPresent);
return(0); // can't remove/replace because item was not found.
}
// Fallthrough action: replace existing item
Debug.Assert(op.Found);
if (HasListChanging(op.List))
{
CallListChanging(op.List, new ListChangeInfo <T>(NotifyCollectionChangedAction.Replace, (int)op.BaseIndex, 0, ListExt.Single(searchItem)));
}
_list[index] = searchItem;
if (index + 1 == _list.Count)
{ // Highest key may change
splitLeft = this;
op.AggregateChanged |= 1;
op.AggregateKey = op.List.GetKey(searchItem);
}
if (GetObserver(op.List) != null)
{
GetObserver(op.List).ItemRemoved(op.Item, this);
GetObserver(op.List).ItemAdded(searchItem, this);
}
return(0);
}
public override AListNode <int, T> Insert(uint index, T item, out AListNode <int, T> splitRight, IAListTreeObserver <int, T> tob)
{
throw new NotSupportedException();
}