// Copies a run of text into a ContentContainer.
// Returns the next node to examine.
private TextTreeNode CopyTextNode(TextTreeTextNode textNode, TextTreeNode haltNode, out ContentContainer container)
{
SplayTreeNode node;
char[] text;
int count;
int symbolOffset;
Invariant.Assert(textNode != haltNode, "Expect at least one node to copy!");
symbolOffset = textNode.GetSymbolOffset(this.TextContainer.Generation);
// Get a count of all the characters we're about to copy.
count = 0;
node = textNode;
do
{
count += textNode.SymbolCount;
node = textNode.GetNextNode();
textNode = node as TextTreeTextNode;
}while (textNode != null && textNode != haltNode);
// Allocate storage.
text = new char[count];
// Copy the text.
TextTreeText.ReadText(this.TextContainer.RootTextBlock, symbolOffset, count, text, 0 /*startIndex*/);
container = new TextContentContainer(text);
return((TextTreeNode)node);
}
// Token: 0x06003D19 RID: 15641 RVA: 0x0011BD4A File Offset: 0x00119F4A
internal TextTreeFixupNode(TextTreeNode previousNode, ElementEdge previousEdge, TextTreeNode nextNode, ElementEdge nextEdge, TextTreeNode firstContainedNode, TextTreeNode lastContainedNode)
{
this._previousNode = previousNode;
this._previousEdge = previousEdge;
this._nextNode = nextNode;
this._nextEdge = nextEdge;
this._firstContainedNode = firstContainedNode;
this._lastContainedNode = lastContainedNode;
}
// Creates a new TextTreeFixupNode instance.
// This ctor should only be called when extracting a single TextTreeTextElementNode.
// previousNode/Edge should point to the node TextPositions will
// move to after synchronizing against the deleted content.
// first/lastContainedNode point to the first and last contained nodes
// of an extracted element node. Positions may move into these nodes.
internal TextTreeFixupNode(TextTreeNode previousNode, ElementEdge previousEdge, TextTreeNode nextNode, ElementEdge nextEdge,
TextTreeNode firstContainedNode, TextTreeNode lastContainedNode)
{
_previousNode = previousNode;
_previousEdge = previousEdge;
_nextNode = nextNode;
_nextEdge = nextEdge;
_firstContainedNode = firstContainedNode;
_lastContainedNode = lastContainedNode;
}
// Token: 0x06003D0D RID: 15629 RVA: 0x0011B8BC File Offset: 0x00119ABC
internal TextTreeDeleteContentUndoUnit(TextContainer tree, TextPointer start, TextPointer end) : base(tree, start.GetSymbolOffset())
{
start.DebugAssertGeneration();
end.DebugAssertGeneration();
Invariant.Assert(start.GetScopingNode() == end.GetScopingNode(), "start/end have different scope!");
TextTreeNode adjacentNode = start.GetAdjacentNode(LogicalDirection.Forward);
TextTreeNode adjacentNode2 = end.GetAdjacentNode(LogicalDirection.Forward);
this._content = this.CopyContent(adjacentNode, adjacentNode2);
}
// Dumps a node and all contained nodes "flat" -- in notation similar to xaml.
internal static void DumpFlat(TextTreeNode node)
{
Debug.Write("<" + GetFlatPrefix(node) + node.DebugId);
if (node.ContainedNode != null)
{
Debug.Write(">");
DumpNodeFlatRecursive(node.GetFirstContainedNode());
Debug.WriteLine("</" + GetFlatPrefix(node) + node.DebugId + ">");
}
else
{
Debug.WriteLine("/>");
}
}
// Dumps a node and all contained nodes "flat" -- in notation similar to xaml.
internal static void DumpFlat(TextTreeNode node)
{
Debug.Write("<" + GetFlatPrefix(node) + node.DebugId);
if (node.ContainedNode != null)
{
Debug.Write(">");
DumpNodeFlatRecursive(node.GetFirstContainedNode());
Debug.WriteLine("</" + GetFlatPrefix(node) + node.DebugId + ">");
}
else
{
Debug.WriteLine("/>");
}
}
//------------------------------------------------------
//
// Private Methods
//
//------------------------------------------------------
#region Private Methods
// Walks the tree from node to the end of its sibling list,
// copying content along the way,
// halting when/if haltNode is encountered. haltNode may be
// null, in which case we walk to the end of the sibling list.
//
// Returns a ContentContainer holding a deep copy of all content
// walked.
//
// This method is called recursively when TextElement nodes
// are encountered.
private ContentContainer CopyContent(TextTreeNode node, TextTreeNode haltNode)
{
ContentContainer firstContainer;
ContentContainer container;
ContentContainer nextContainer;
TextTreeTextNode textNode;
TextTreeObjectNode objectNode;
TextTreeTextElementNode elementNode;
firstContainer = null;
container = null;
while (node != haltNode && node != null)
{
textNode = node as TextTreeTextNode;
if (textNode != null)
{
node = CopyTextNode(textNode, haltNode, out nextContainer);
}
else
{
objectNode = node as TextTreeObjectNode;
if (objectNode != null)
{
node = CopyObjectNode(objectNode, out nextContainer);
}
else
{
Invariant.Assert(node is TextTreeTextElementNode, "Unexpected TextTreeNode type!");
elementNode = (TextTreeTextElementNode)node;
node = CopyElementNode(elementNode, out nextContainer);
}
}
if (container == null)
{
firstContainer = nextContainer;
}
else
{
container.NextContainer = nextContainer;
}
container = nextContainer;
}
return(firstContainer);
}
// Token: 0x06003D13 RID: 15635 RVA: 0x0011BAC8 File Offset: 0x00119CC8
private TextTreeNode CopyTextNode(TextTreeTextNode textNode, TextTreeNode haltNode, out TextTreeDeleteContentUndoUnit.ContentContainer container)
{
Invariant.Assert(textNode != haltNode, "Expect at least one node to copy!");
int symbolOffset = textNode.GetSymbolOffset(base.TextContainer.Generation);
int num = 0;
SplayTreeNode nextNode;
do
{
num += textNode.SymbolCount;
nextNode = textNode.GetNextNode();
textNode = (nextNode as TextTreeTextNode);
}while (textNode != null && textNode != haltNode);
char[] array = new char[num];
TextTreeText.ReadText(base.TextContainer.RootTextBlock, symbolOffset, num, array, 0);
container = new TextTreeDeleteContentUndoUnit.TextContentContainer(array);
return((TextTreeNode)nextNode);
}
// Token: 0x06003D12 RID: 15634 RVA: 0x0011BA44 File Offset: 0x00119C44
private TextTreeDeleteContentUndoUnit.ContentContainer CopyContent(TextTreeNode node, TextTreeNode haltNode)
{
TextTreeDeleteContentUndoUnit.ContentContainer result = null;
TextTreeDeleteContentUndoUnit.ContentContainer contentContainer = null;
while (node != haltNode && node != null)
{
TextTreeTextNode textTreeTextNode = node as TextTreeTextNode;
TextTreeDeleteContentUndoUnit.ContentContainer contentContainer2;
if (textTreeTextNode != null)
{
node = this.CopyTextNode(textTreeTextNode, haltNode, out contentContainer2);
}
else
{
TextTreeObjectNode textTreeObjectNode = node as TextTreeObjectNode;
if (textTreeObjectNode != null)
{
node = this.CopyObjectNode(textTreeObjectNode, out contentContainer2);
}
else
{
Invariant.Assert(node is TextTreeTextElementNode, "Unexpected TextTreeNode type!");
TextTreeTextElementNode elementNode = (TextTreeTextElementNode)node;
node = this.CopyElementNode(elementNode, out contentContainer2);
}
}
if (contentContainer == null)
{
result = contentContainer2;
}
else
{
contentContainer.NextContainer = contentContainer2;
}
contentContainer = contentContainer2;
}
return(result);
}
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
// Creates a new TextTreeFixupNode instance.
// previousNode/Edge should point to the node TextPositions will
// move to after synchronizing against the deleted content.
internal TextTreeFixupNode(TextTreeNode previousNode, ElementEdge previousEdge, TextTreeNode nextNode, ElementEdge nextEdge) :
this(previousNode, previousEdge, nextNode, nextEdge, null, null)
{
}
// Copies a run of text into a ContentContainer.
// Returns the next node to examine.
private TextTreeNode CopyTextNode(TextTreeTextNode textNode, TextTreeNode haltNode, out ContentContainer container)
{
SplayTreeNode node;
char[] text;
int count;
int symbolOffset;
Invariant.Assert(textNode != haltNode, "Expect at least one node to copy!");
symbolOffset = textNode.GetSymbolOffset(this.TextContainer.Generation);
// Get a count of all the characters we're about to copy.
count = 0;
node = textNode;
do
{
count += textNode.SymbolCount;
node = textNode.GetNextNode();
textNode = node as TextTreeTextNode;
}
while (textNode != null && textNode != haltNode);
// Allocate storage.
text = new char[count];
// Copy the text.
TextTreeText.ReadText(this.TextContainer.RootTextBlock, symbolOffset, count, text, 0 /*startIndex*/);
container = new TextContentContainer(text);
return (TextTreeNode)node;
}
// Returns the symbol offset within the TextContainer of this Position.
internal static int GetSymbolOffset(TextContainer tree, TextTreeNode node, ElementEdge edge)
{
int offset;
switch (edge)
{
case ElementEdge.BeforeStart:
offset = node.GetSymbolOffset(tree.Generation);
break;
case ElementEdge.AfterStart:
offset = node.GetSymbolOffset(tree.Generation) + 1;
break;
case ElementEdge.BeforeEnd:
offset = node.GetSymbolOffset(tree.Generation) + node.SymbolCount - 1;
break;
case ElementEdge.AfterEnd:
offset = node.GetSymbolOffset(tree.Generation) + node.SymbolCount;
break;
default:
Invariant.Assert(false, "Unknown value for position edge");
offset = 0;
break;
}
return offset;
}
// Fires Change events for IMELeftEdgeCharCount deltas to a node after it
// moves out of position such that it is no longer the leftmost child
// of its parent.
private void RaiseEventForFormerFirstIMEVisibleNode(TextTreeNode node)
{
TextPointer startEdgePosition = new TextPointer(this, node, ElementEdge.BeforeStart);
// Next node was the old first node. Its IMECharCount
// just bumped up, report that.
AddChange(startEdgePosition, /* symbolCount */ 0, /* IMECharCount */ 1, PrecursorTextChangeType.ContentAdded);
}
internal static TextTreeNode GetAdjacentNode(TextTreeNode node, ElementEdge edge, LogicalDirection direction)
{
TextTreeNode adjacentNode;
adjacentNode = GetAdjacentSiblingNode(node, edge, direction);
if (adjacentNode == null)
{
// We're the first or last child, try the parent.
if (edge == ElementEdge.AfterStart || edge == ElementEdge.BeforeEnd)
{
adjacentNode = node;
}
else
{
adjacentNode = (TextTreeNode)node.GetContainingNode();
}
}
return adjacentNode;
}
// For any logical position (location between two symbols) there are two
// possible node/edge pairs. This method choses the pair that fits a
// specified gravity, such that future inserts won't require that a text
// position be moved, based on its gravity, at the node/edge pair.
private static void RepositionForGravity(ref TextTreeNode node, ref ElementEdge edge, LogicalDirection gravity)
{
SplayTreeNode newNode;
ElementEdge newEdge;
newNode = node;
newEdge = edge;
switch (edge)
{
case ElementEdge.BeforeStart:
if (gravity == LogicalDirection.Backward)
{
newNode = node.GetPreviousNode();
newEdge = ElementEdge.AfterEnd;
if (newNode == null)
{
newNode = node.GetContainingNode();
newEdge = ElementEdge.AfterStart;
}
}
break;
case ElementEdge.AfterStart:
if (gravity == LogicalDirection.Forward)
{
newNode = node.GetFirstContainedNode();
newEdge = ElementEdge.BeforeStart;
if (newNode == null)
{
newNode = node;
newEdge = ElementEdge.BeforeEnd;
}
}
break;
case ElementEdge.BeforeEnd:
if (gravity == LogicalDirection.Backward)
{
newNode = node.GetLastContainedNode();
newEdge = ElementEdge.AfterEnd;
if (newNode == null)
{
newNode = node;
newEdge = ElementEdge.AfterStart;
}
}
break;
case ElementEdge.AfterEnd:
if (gravity == LogicalDirection.Forward)
{
newNode = node.GetNextNode();
newEdge = ElementEdge.BeforeStart;
if (newNode == null)
{
newNode = node.GetContainingNode();
newEdge = ElementEdge.BeforeEnd;
}
}
break;
}
node = (TextTreeNode)newNode;
edge = newEdge;
}
// Inc/decs the position ref counts on TextTreeTextNodes as the navigator
// is repositioned.
// If the new ref is to a TextTreeTextNode, the node may be split.
// Returns the actual node referenced, which will always be newNode,
// unless newNode is a TextTreeTextNode that gets split. The caller
// should use the returned node to position navigators.
private TextTreeNode AdjustRefCounts(TextTreeNode newNode, ElementEdge newNodeEdge, TextTreeNode oldNode, ElementEdge oldNodeEdge)
{
TextTreeNode node;
// This test should walk the tree upwards to catch all errors...probably not worth the slowdown though.
Invariant.Assert(oldNode.ParentNode == null || oldNode.IsChildOfNode(oldNode.ParentNode), "Trying to add ref a dead node!");
Invariant.Assert(newNode.ParentNode == null || newNode.IsChildOfNode(newNode.ParentNode), "Trying to add ref a dead node!");
node = newNode;
if (newNode != oldNode || newNodeEdge != oldNodeEdge)
{
node = newNode.IncrementReferenceCount(newNodeEdge);
oldNode.DecrementReferenceCount(oldNodeEdge);
}
return node;
}
// Called by the TextPointer ctor. Initializes this instance.
private void Initialize(TextContainer tree, TextTreeNode node, ElementEdge edge, LogicalDirection gravity, uint generation,
bool caretUnitBoundaryCache, bool isCaretUnitBoundaryCacheValid, uint layoutGeneration)
{
_tree = tree;
// Fixup of the target node based on gravity.
// Positions always cling to a node edge that matches their gravity,
// so that insert ops never affect the position.
RepositionForGravity(ref node, ref edge, gravity);
SetNodeAndEdge(node.IncrementReferenceCount(edge), edge);
_generation = generation;
this.CaretUnitBoundaryCache = caretUnitBoundaryCache;
this.IsCaretUnitBoundaryCacheValid = isCaretUnitBoundaryCacheValid;
_layoutGeneration = layoutGeneration;
VerifyFlags();
tree.AssertTree();
AssertState();
}
// Returns the symbol type preceding thisPosition.
internal static TextPointerContext GetPointerContextBackward(TextTreeNode node, ElementEdge edge)
{
TextPointerContext symbolType;
TextTreeNode previousNode;
TextTreeNode lastChildNode;
switch (edge)
{
case ElementEdge.BeforeStart:
previousNode = (TextTreeNode)node.GetPreviousNode();
if (previousNode != null)
{
symbolType = previousNode.GetPointerContext(LogicalDirection.Backward);
}
else
{
// The root node is special, there's no ElementStart/End, so test for null parent.
Invariant.Assert(node.GetContainingNode() != null, "Bad position!"); // Illegal to be at root BeforeStart.
symbolType = (node.GetContainingNode() is TextTreeRootNode) ? TextPointerContext.None : TextPointerContext.ElementStart;
}
break;
case ElementEdge.AfterStart:
// The root node is special, there's no ElementStart/End, so test for null parent.
Invariant.Assert(node.ParentNode != null || node is TextTreeRootNode, "Inconsistent node.ParentNode");
symbolType = (node.ParentNode != null) ? TextPointerContext.ElementStart : TextPointerContext.None;
break;
case ElementEdge.BeforeEnd:
lastChildNode = (TextTreeNode)node.GetLastContainedNode();
if (lastChildNode != null)
{
symbolType = lastChildNode.GetPointerContext(LogicalDirection.Backward);
}
else
{
goto case ElementEdge.AfterStart;
}
break;
case ElementEdge.AfterEnd:
symbolType = node.GetPointerContext(LogicalDirection.Backward);
break;
default:
Invariant.Assert(false, "Unknown ElementEdge value");
symbolType = TextPointerContext.Text;
break;
}
return symbolType;
}
internal static TextPointerContext GetPointerContextForward(TextTreeNode node, ElementEdge edge)
{
TextTreeNode nextNode;
TextTreeNode firstContainedNode;
TextPointerContext symbolType;
switch (edge)
{
case ElementEdge.BeforeStart:
symbolType = node.GetPointerContext(LogicalDirection.Forward);
break;
case ElementEdge.AfterStart:
if (node.ContainedNode != null)
{
firstContainedNode = (TextTreeNode)node.GetFirstContainedNode();
symbolType = firstContainedNode.GetPointerContext(LogicalDirection.Forward);
}
else
{
goto case ElementEdge.BeforeEnd;
}
break;
case ElementEdge.BeforeEnd:
// The root node is special, there's no ElementStart/End, so test for null parent.
Invariant.Assert(node.ParentNode != null || node is TextTreeRootNode, "Inconsistent node.ParentNode");
symbolType = (node.ParentNode != null) ? TextPointerContext.ElementEnd : TextPointerContext.None;
break;
case ElementEdge.AfterEnd:
nextNode = (TextTreeNode)node.GetNextNode();
if (nextNode != null)
{
symbolType = nextNode.GetPointerContext(LogicalDirection.Forward);
}
else
{
// The root node is special, there's no ElementStart/End, so test for null parent.
Invariant.Assert(node.GetContainingNode() != null, "Bad position!"); // Illegal to be at root AfterEnd.
symbolType = (node.GetContainingNode() is TextTreeRootNode) ? TextPointerContext.None : TextPointerContext.ElementEnd;
}
break;
default:
Invariant.Assert(false, "Unreachable code.");
symbolType = TextPointerContext.Text;
break;
}
return symbolType;
}
// Finds the previous run, returned as a node/edge pair.
// Returns false if there is no preceding run, in which case node/edge will match the input position.
// The returned node/edge pair respects the input positon's gravity.
internal static bool GetPreviousNodeAndEdge(TextTreeNode sourceNode, ElementEdge sourceEdge, bool plainTextOnly, out TextTreeNode node, out ElementEdge edge)
{
SplayTreeNode currentNode;
SplayTreeNode newNode;
SplayTreeNode containingNode;
bool startedAdjacentToTextNode;
bool endedAdjacentToTextNode;
node = sourceNode;
edge = sourceEdge;
newNode = node;
currentNode = node;
// If we started next to a TextTreeTextNode, and the next node
// is also a TextTreeTextNode, then skip past the second node
// as well -- multiple text nodes count as a single Move run.
do
{
startedAdjacentToTextNode = false;
endedAdjacentToTextNode = false;
switch (edge)
{
case ElementEdge.BeforeStart:
newNode = currentNode.GetPreviousNode();
if (newNode != null)
{
// Move to next node/last child;
if (newNode is TextTreeTextElementNode)
{
// Move to previous node last child/previous node
edge = ElementEdge.BeforeEnd;
}
else
{
// Move to previous previous node/previous node.
startedAdjacentToTextNode = newNode is TextTreeTextNode;
endedAdjacentToTextNode = startedAdjacentToTextNode && newNode.GetPreviousNode() is TextTreeTextNode;
}
}
else
{
containingNode = currentNode.GetContainingNode();
if (!(containingNode is TextTreeRootNode))
{
// Move to parent.
newNode = containingNode;
}
}
break;
case ElementEdge.AfterStart:
newNode = currentNode.GetPreviousNode();
if (newNode != null)
{
endedAdjacentToTextNode = newNode is TextTreeTextNode;
// Move to previous node;
edge = ElementEdge.AfterEnd;
}
else
{
// Move to inner edge of parent.
newNode = currentNode.GetContainingNode();
}
break;
case ElementEdge.BeforeEnd:
newNode = currentNode.GetLastContainedNode();
if (newNode != null)
{
// Move to penultimate child/last child or inner edge of last child.
if (newNode is TextTreeTextElementNode)
{
edge = ElementEdge.BeforeEnd;
}
else
{
startedAdjacentToTextNode = newNode is TextTreeTextNode;
endedAdjacentToTextNode = startedAdjacentToTextNode && newNode.GetPreviousNode() is TextTreeTextNode;
edge = ElementEdge.BeforeStart;
}
}
else if (currentNode is TextTreeTextElementNode)
{
// Move to next node.
newNode = currentNode;
edge = ElementEdge.BeforeStart;
}
else
{
Invariant.Assert(currentNode is TextTreeRootNode, "currentNode is expected to be a TextTreeRootNode");
// This is the root node, leave newNode null.
}
break;
case ElementEdge.AfterEnd:
newNode = currentNode.GetLastContainedNode();
if (newNode != null)
{
// Move to inner edge/last child.
}
else if (currentNode is TextTreeTextElementNode)
{
// Move to opposite edge.
newNode = currentNode;
edge = ElementEdge.AfterStart;
}
else
{
// Move to previous node.
startedAdjacentToTextNode = currentNode is TextTreeTextNode;
edge = ElementEdge.AfterStart;
goto case ElementEdge.AfterStart;
}
break;
default:
Invariant.Assert(false, "Unknown ElementEdge value");
break;
}
currentNode = newNode;
// Multiple text nodes count as a single Move run.
// Instead of iterating through N text nodes, exploit
// the fact (when we can) that text nodes are only ever contained in
// runs with no other content. Jump straight to the start.
if (startedAdjacentToTextNode && endedAdjacentToTextNode && plainTextOnly)
{
newNode = newNode.GetContainingNode();
Invariant.Assert(newNode is TextTreeRootNode);
if (edge == ElementEdge.AfterEnd)
{
edge = ElementEdge.AfterStart;
}
else
{
newNode = newNode.GetFirstContainedNode();
Invariant.Assert(newNode != null);
Invariant.Assert(edge == ElementEdge.BeforeStart);
}
break;
}
}
while (startedAdjacentToTextNode && endedAdjacentToTextNode);
if (newNode != null)
{
node = (TextTreeNode)newNode;
}
return (newNode != null);
}
// Dumps a node and all its children.
internal static void Dump(TextTreeNode node)
{
DumpNodeRecursive(node, 0);
}
internal bool GetPreviousNodeAndEdge(out TextTreeNode node, out ElementEdge edge)
{
DebugAssertGeneration();
return GetPreviousNodeAndEdge(_node, this.Edge, _tree.PlainTextOnly, out node, out edge);
}
// Positions this navigator at a node/edge pair.
// Node/edge are adjusted based on the current gravity.
private void MoveToNode(TextContainer tree, TextTreeNode node, ElementEdge edge)
{
RepositionForGravity(ref node, ref edge, GetGravityInternal());
_tree = tree;
SetNodeAndEdge(AdjustRefCounts(node, edge, _node, this.Edge), edge);
_generation = tree.PositionGeneration;
}
// Fires Change events for IMELeftEdgeCharCount deltas to a node after it
// moves into position such that it is the leftmost child
// of its parent.
private void RaiseEventForNewFirstIMEVisibleNode(TextTreeNode node)
{
TextPointer startEdgePosition = new TextPointer(this, node, ElementEdge.BeforeStart);
// node was the old second node. Its IMECharCount
// just dropped down, report that.
AddChange(startEdgePosition, /* symbolCount */ 0, /* IMECharCount */ 1, PrecursorTextChangeType.ContentRemoved);
}
// Repositions the TextPointer and clears any relevant caches.
private void SetNodeAndEdge(TextTreeNode node, ElementEdge edge)
{
Invariant.Assert(edge == ElementEdge.BeforeStart ||
edge == ElementEdge.AfterStart ||
edge == ElementEdge.BeforeEnd ||
edge == ElementEdge.AfterEnd);
_node = node;
_flags = (_flags & ~(uint)Flags.EdgeMask) | (uint)edge;
VerifyFlags();
// Always clear the caret unit boundary cache when we move to a new position.
this.IsCaretUnitBoundaryCacheValid = false;
}
internal static TextTreeNode GetScopingNode(TextTreeNode node, ElementEdge edge)
{
TextTreeNode scopingNode;
switch (edge)
{
case ElementEdge.BeforeStart:
case ElementEdge.AfterEnd:
scopingNode = (TextTreeNode)node.GetContainingNode();
break;
case ElementEdge.AfterStart:
case ElementEdge.BeforeEnd:
default:
scopingNode = node;
break;
}
return scopingNode;
}
// Finds a node/edge pair matching a given char offset in the tree.
// If the pair matches a character within a text node, the text node is split.
internal void GetNodeAndEdgeAtCharOffset(int charOffset, out TextTreeNode node, out ElementEdge edge)
{
int nodeCharOffset;
int siblingTreeCharOffset;
bool checkZeroWidthNode;
// Offset zero/SymbolCount-1 are before/after the root node, which
// is an illegal position -- you can't add or remove content there
// and it's never exposed publicly.
Invariant.Assert(charOffset >= 0 && charOffset <= this.IMECharCount, "Bogus char offset!");
if (this.IMECharCount == 0)
{
node = null;
edge = ElementEdge.BeforeStart;
return;
}
// If this flag is set true on exit, we need to consider the case
// where we've found a "zero-width" (SymbolCount == 0) text node.
// Zero width nodes needs special handling, since they are logically
// part of a following or preceding node.
checkZeroWidthNode = false;
// Find the node.
node = _rootNode;
nodeCharOffset = 0;
// Each iteration walks through one tree.
while (true)
{
int leftEdgeCharCount = 0;
TextTreeTextElementNode textElementNode = node as TextTreeTextElementNode;
if (textElementNode != null)
{
leftEdgeCharCount = textElementNode.IMELeftEdgeCharCount;
if (leftEdgeCharCount > 0)
{
if (charOffset == nodeCharOffset)
{
edge = ElementEdge.BeforeStart;
break;
}
if (charOffset == nodeCharOffset + leftEdgeCharCount)
{
edge = ElementEdge.AfterStart;
break;
}
}
}
else if (node is TextTreeTextNode || node is TextTreeObjectNode)
{
if (charOffset == nodeCharOffset)
{
edge = ElementEdge.BeforeStart;
checkZeroWidthNode = true;
break;
}
if (charOffset == nodeCharOffset + node.IMECharCount)
{
edge = ElementEdge.AfterEnd;
checkZeroWidthNode = true;
break;
}
}
// No child node? That means we're inside a TextTreeTextNode.
if (node.ContainedNode == null)
{
Invariant.Assert(node is TextTreeTextNode);
// Need to split the TextTreeTextNode.
// Here we want a character buried inside a single node, split
// the node open....
node = ((TextTreeTextNode)node).Split(charOffset - nodeCharOffset, ElementEdge.AfterEnd);
edge = ElementEdge.BeforeStart;
break;
}
// Need to look into one of the child nodes.
node = (TextTreeNode)node.ContainedNode;
nodeCharOffset += leftEdgeCharCount; // Skip over the parent element start edge.
// Walk down the sibling tree.
node = (TextTreeNode)node.GetSiblingAtCharOffset(charOffset - nodeCharOffset, out siblingTreeCharOffset);
nodeCharOffset += siblingTreeCharOffset;
}
// If we're on a zero-width TextTreeTextNode we need some special handling.
if (checkZeroWidthNode)
{
node = (TextTreeNode)AdjustForZeroWidthNode(node, edge);
}
}
// Dumps a node and all its children.
internal static void Dump(TextTreeNode node)
{
DumpNodeRecursive(node, 0);
}
// Does a deep extract of all top-level TextElements between two positions.
// Returns the combined symbol count of all extracted elements.
// Each extracted element (and its children) are moved into a private tree.
// This insures that outside references to the TextElement can still use
// the TextElements freely, inserting or removing content, etc.
//
// Also calls AddLogicalChild on any top-level UIElements encountered.
private int CutTopLevelLogicalNodes(TextTreeNode containingNode, TextPointer startPosition, TextPointer endPosition, out int charCount)
{
SplayTreeNode node;
SplayTreeNode nextNode;
SplayTreeNode stopNode;
TextTreeTextElementNode elementNode;
TextTreeObjectNode uiElementNode;
char[] elementText;
int symbolCount;
TextContainer tree;
TextPointer newTreeStart;
DependencyObject logicalParent;
object currentLogicalChild;
Invariant.Assert(startPosition.GetScopingNode() == endPosition.GetScopingNode(), "startPosition/endPosition not in same sibling tree!");
node = startPosition.GetAdjacentSiblingNode(LogicalDirection.Forward);
stopNode = endPosition.GetAdjacentSiblingNode(LogicalDirection.Forward);
symbolCount = 0;
charCount = 0;
logicalParent = containingNode.GetLogicalTreeNode();
while (node != stopNode)
{
currentLogicalChild = null;
// Get the next node now, before we extract any TextElementNodes.
nextNode = node.GetNextNode();
elementNode = node as TextTreeTextElementNode;
if (elementNode != null)
{
// Grab the IMECharCount before we modify the node.
// This value depends on the node's current context.
int imeCharCountInOriginalContainer = elementNode.IMECharCount;
// Cut and record the matching symbols.
elementText = TextTreeText.CutText(_rootNode.RootTextBlock, elementNode.GetSymbolOffset(this.Generation), elementNode.SymbolCount);
// Rip the element out of its sibling tree.
// textElementNode.TextElement's TextElementNode will be updated
// with a deep copy of all contained nodes. We need a deep copy
// to ensure the new element/tree has no TextPointer references.
ExtractElementFromSiblingTree(containingNode, elementNode, true /* deep */);
// Assert that the TextElement now points to a new TextElementNode, not the original one.
Invariant.Assert(elementNode.TextElement.TextElementNode != elementNode);
// We want to start referring to the copied node, update elementNode.
elementNode = elementNode.TextElement.TextElementNode;
UpdateContainerSymbolCount(containingNode, -elementNode.SymbolCount, -imeCharCountInOriginalContainer);
NextGeneration(true /* deletedContent */);
// Stick it in a private tree so it's safe for the outside world to play with.
tree = new TextContainer(null, false /* plainTextOnly */);
newTreeStart = tree.Start;
tree.InsertElementToSiblingTree(newTreeStart, newTreeStart, elementNode);
Invariant.Assert(elementText.Length == elementNode.SymbolCount);
tree.UpdateContainerSymbolCount(elementNode.GetContainingNode(), elementNode.SymbolCount, elementNode.IMECharCount);
tree.DemandCreateText();
TextTreeText.InsertText(tree.RootTextBlock, 1 /* symbolOffset */, elementText);
tree.NextGeneration(false /* deletedContent */);
currentLogicalChild = elementNode.TextElement;
// Keep a running total of how many symbols we've removed.
symbolCount += elementNode.SymbolCount;
charCount += imeCharCountInOriginalContainer;
}
else
{
uiElementNode = node as TextTreeObjectNode;
if (uiElementNode != null)
{
currentLogicalChild = uiElementNode.EmbeddedElement;
}
}
// Remove the child from the logical tree
LogicalTreeHelper.RemoveLogicalChild(logicalParent, currentLogicalChild);
node = nextNode;
}
if (symbolCount > 0)
{
startPosition.SyncToTreeGeneration();
endPosition.SyncToTreeGeneration();
}
return symbolCount;
}
// Increments the position reference counts on nodes immediately
// preceding and following a delete operation.
//
// Whenever we delete a span of content, we have to worry about any
// positions still referencing the deleted content. They have enough
// information to find their way back to the surrounding nodes, but
// we need to increment the ref count on those nodes now so that they'll
// still be around when the positions need them.
//
// Because incrementing a ref count on a text node edge may involve
// splitting the text node, this method takes refs to nodes and will
// update the refs if a node is split.
//
// Called by DeleteContentFromSiblingTree and ExtractElementInternal.
private void AdjustRefCountsForContentDelete(ref TextTreeNode previousNode, ElementEdge previousEdge,
ref TextTreeNode nextNode, ElementEdge nextEdge,
TextTreeNode middleSubTree)
{
bool leftEdgeReferenceCount;
bool rightEdgeReferenceCount;
leftEdgeReferenceCount = false;
rightEdgeReferenceCount = false;
// Get the count of all positions referencing text node edges across the deleted content.
GetReferenceCounts((TextTreeNode)middleSubTree.GetMinSibling(), ref leftEdgeReferenceCount, ref rightEdgeReferenceCount);
previousNode = previousNode.IncrementReferenceCount(previousEdge, rightEdgeReferenceCount);
nextNode = nextNode.IncrementReferenceCount(nextEdge, leftEdgeReferenceCount);
}
// Returns the TextTreeTextNode in the direction indicated bordering
// a TextPointer, or null if no such node exists.
internal static TextTreeTextNode GetAdjacentTextNodeSibling(TextTreeNode node, ElementEdge edge, LogicalDirection direction)
{
return GetAdjacentSiblingNode(node, edge, direction) as TextTreeTextNode;
}
//------------------------------------------------------
//
// Private Methods
//
//------------------------------------------------------
#region Private Methods
// Walks the tree from node to the end of its sibling list,
// copying content along the way,
// halting when/if haltNode is encountered. haltNode may be
// null, in which case we walk to the end of the sibling list.
//
// Returns a ContentContainer holding a deep copy of all content
// walked.
//
// This method is called recursively when TextElement nodes
// are encountered.
private ContentContainer CopyContent(TextTreeNode node, TextTreeNode haltNode)
{
ContentContainer firstContainer;
ContentContainer container;
ContentContainer nextContainer;
TextTreeTextNode textNode;
TextTreeObjectNode objectNode;
TextTreeTextElementNode elementNode;
firstContainer = null;
container = null;
while (node != haltNode && node != null)
{
textNode = node as TextTreeTextNode;
if (textNode != null)
{
node = CopyTextNode(textNode, haltNode, out nextContainer);
}
else
{
objectNode = node as TextTreeObjectNode;
if (objectNode != null)
{
node = CopyObjectNode(objectNode, out nextContainer);
}
else
{
Invariant.Assert(node is TextTreeTextElementNode, "Unexpected TextTreeNode type!");
elementNode = (TextTreeTextElementNode)node;
node = CopyElementNode(elementNode, out nextContainer);
}
}
if (container == null)
{
firstContainer = nextContainer;
}
else
{
container.NextContainer = nextContainer;
}
container = nextContainer;
}
return firstContainer;
}
// Increments the position reference counts on nodes immediately
// preceding and following a delete operation on a single TextElementNode.
// This is similar to AdjustRefCountsForContentDelete, except that
// in this case we deleting a single node, and positions at the
// BeforeStart/AfterEnd edges may move into contained content, which
// is still live in the tree.
//
// Whenever we delete a span of content, we have to worry about any
// positions still referencing the deleted content. They have enough
// information to find their way back to the surrounding nodes, but
// we need to increment the ref count on those nodes now so that they'll
// still be around when the positions need them.
//
// Because incrementing a ref count on a text node edge may involve
// splitting the text node, this method takes refs to nodes and will
// update the refs if a node is split.
//
// Called by ExtractElementFromSiblingTree.
private void AdjustRefCountsForShallowDelete(ref TextTreeNode previousNode, ElementEdge previousEdge,
ref TextTreeNode nextNode,ElementEdge nextEdge,
ref TextTreeNode firstContainedNode, ref TextTreeNode lastContainedNode,
TextTreeTextElementNode extractedElementNode)
{
previousNode = previousNode.IncrementReferenceCount(previousEdge, extractedElementNode.AfterStartReferenceCount);
nextNode = nextNode.IncrementReferenceCount(nextEdge, extractedElementNode.BeforeEndReferenceCount);
if (firstContainedNode != null)
{
firstContainedNode = firstContainedNode.IncrementReferenceCount(ElementEdge.BeforeStart, extractedElementNode.BeforeStartReferenceCount);
}
else
{
nextNode = nextNode.IncrementReferenceCount(nextEdge, extractedElementNode.BeforeStartReferenceCount);
}
if (lastContainedNode != null)
{
lastContainedNode = lastContainedNode.IncrementReferenceCount(ElementEdge.AfterEnd, extractedElementNode.AfterEndReferenceCount);
}
else
{
previousNode = previousNode.IncrementReferenceCount(previousEdge, extractedElementNode.AfterEndReferenceCount);
}
}
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
// Creates a new TextTreeFixupNode instance.
// previousNode/Edge should point to the node TextPositions will
// move to after synchronizing against the deleted content.
internal TextTreeFixupNode(TextTreeNode previousNode, ElementEdge previousEdge, TextTreeNode nextNode, ElementEdge nextEdge) :
this(previousNode, previousEdge, nextNode, nextEdge, null, null)
{
}
// Returns a copy of a sibling tree. node is expected to be the first sibling.
private TextTreeNode DeepCopyContainedNodes(TextTreeNode node)
{
TextTreeNode rootClone;
TextTreeNode previousClone;
TextTreeNode clone;
TextTreeTextElementNode elementNode;
rootClone = null;
previousClone = null;
do
{
elementNode = node as TextTreeTextElementNode;
if (elementNode != null)
{
clone = DeepCopy(elementNode);
}
else
{
clone = node.Clone();
}
// clone will be null in one case: if we're trying to clone an
// empty TextNode. We can skip empty TextNodes (symbol count == 0)
// because we know the clones have no TextPointer references, so
// an empty node serves no purpose.
Invariant.Assert(clone != null || node is TextTreeTextNode && node.SymbolCount == 0);
if (clone != null)
{
clone.ParentNode = previousClone;
if (previousClone != null)
{
previousClone.RightChildNode = clone;
}
else
{
Invariant.Assert(clone.Role == SplayTreeNodeRole.LocalRoot);
// Remember the first clone created.
rootClone = clone;
}
previousClone = clone;
}
node = (TextTreeNode)node.GetNextNode();
}
while (node != null);
return rootClone;
}
internal static TextTreeNode GetAdjacentSiblingNode(TextTreeNode node, ElementEdge edge, LogicalDirection direction)
{
SplayTreeNode sibling;
if (direction == LogicalDirection.Forward)
{
switch (edge)
{
case ElementEdge.BeforeStart:
sibling = node;
break;
case ElementEdge.AfterStart:
sibling = node.GetFirstContainedNode();
break;
case ElementEdge.BeforeEnd:
default:
sibling = null;
break;
case ElementEdge.AfterEnd:
sibling = node.GetNextNode();
break;
}
}
else // direction == LogicalDirection.Backward
{
switch (edge)
{
case ElementEdge.BeforeStart:
sibling = node.GetPreviousNode();
break;
case ElementEdge.AfterStart:
default:
sibling = null;
break;
case ElementEdge.BeforeEnd:
sibling = node.GetLastContainedNode();
break;
case ElementEdge.AfterEnd:
sibling = node;
break;
}
}
return (TextTreeNode)sibling;
}
private void AssertTreeRecursive(TextTreeNode containingNode)
{
TextTreeNode node;
if (containingNode.ContainedNode == null)
{
Invariant.Assert(containingNode.ParentNode == null || containingNode.ParentNode.ContainedNode == containingNode);
return;
}
Invariant.Assert(containingNode.ContainedNode.ParentNode == containingNode);
for (node = (TextTreeNode)containingNode.ContainedNode.GetMinSibling(); node != null; node = (TextTreeNode)node.GetNextNode())
{
if (node != containingNode.ContainedNode)
{
Invariant.Assert(node.ParentNode.LeftChildNode == node || node.ParentNode.RightChildNode == node);
}
Invariant.Assert(node.SymbolCount >= 0);
if (node.SymbolCount == 0)
{
Invariant.Assert(node is TextTreeTextNode);
Invariant.Assert(node.BeforeStartReferenceCount > 0 || node.AfterEndReferenceCount > 0);
}
if (node.ContainedNode != null)
{
AssertTreeRecursive((TextTreeNode)node.ContainedNode);
}
}
}
// Sums the reference counts for a node and all following or contained nodes.
private void GetReferenceCounts(TextTreeNode node, ref bool leftEdgeReferenceCount, ref bool rightEdgeReferenceCount)
{
do
{
// We can combine BeforeStart/BeforeEnd and AfterStart/AfterEnd because
// they include all positions with equal gravity.
leftEdgeReferenceCount |= node.BeforeStartReferenceCount || node.BeforeEndReferenceCount;
rightEdgeReferenceCount |= node.AfterStartReferenceCount || node.AfterEndReferenceCount;
if (node.ContainedNode != null)
{
GetReferenceCounts((TextTreeNode)node.ContainedNode.GetMinSibling(), ref leftEdgeReferenceCount, ref rightEdgeReferenceCount);
}
node = (TextTreeNode)node.GetNextNode();
}
while (node != null);
}
// Creates a new TextPointer instance.
internal TextPointer(TextContainer tree, TextTreeNode node, ElementEdge edge, LogicalDirection direction)
{
Initialize(tree, node, edge, direction, tree.PositionGeneration, false, false, tree.LayoutGeneration);
}