/// <summary>
/// Creates a selection object spanning the portion of 'startNode'
/// specified by 'locatorPart'.
/// </summary>
/// <param name="locatorPart">locator part specifying data to be spanned</param>
/// <param name="startNode">the node to be spanned by the created
/// selection</param>
/// <param name="attachmentLevel">set to AttachmentLevel.Full if the entire range of text
/// was resolved, otherwise set to StartPortion, MiddlePortion, or EndPortion based on
/// which part of the range was resolved</param>
/// <returns>a selection spanning the portion of 'startNode' specified by
/// 'locatorPart', null if selection described by locator part could not be
/// recreated</returns>
/// <exception cref="ArgumentNullException">locatorPart or startNode are
/// null</exception>
/// <exception cref="ArgumentException">locatorPart is of the incorrect type</exception>
public override Object ResolveLocatorPart(ContentLocatorPart locatorPart, DependencyObject startNode, out AttachmentLevel attachmentLevel)
{
if (startNode == null)
throw new ArgumentNullException("startNode");
if (locatorPart == null)
throw new ArgumentNullException("locatorPart");
if (CharacterRangeElementName != locatorPart.PartType)
throw new ArgumentException(SR.Get(SRID.IncorrectLocatorPartType, locatorPart.PartType.Namespace + ":" + locatorPart.PartType.Name), "locatorPart");
// First we extract the offset and length of the
// text range from the locator part.
int startOffset = 0;
int endOffset = 0;
string stringCount = locatorPart.NameValuePairs[CountAttribute];
if (stringCount == null)
throw new ArgumentException(SR.Get(SRID.InvalidLocatorPart, TextSelectionProcessor.CountAttribute));
int count = Int32.Parse(stringCount,NumberFormatInfo.InvariantInfo);
TextAnchor anchor = new TextAnchor();
attachmentLevel = AttachmentLevel.Unresolved;
for (int i = 0; i < count; i++)
{
GetLocatorPartSegmentValues(locatorPart, i, out startOffset, out endOffset);
// Now we grab the TextRange so we can create a selection.
// TextBox doesn't expose its internal TextRange so we use
// its API for creating and getting the selection.
ITextPointer elementStart;
ITextPointer elementEnd;
// If we can't get the start/end of the node then we can't resolve the locator part
if (!GetNodesStartAndEnd(startNode, out elementStart, out elementEnd))
return null;
// If the offset is not withing the element's text range we return null
int textRangeLength = elementStart.GetOffsetToPosition(elementEnd);
if (startOffset > textRangeLength)
return null;
ITextPointer start = elementStart.CreatePointer(startOffset);// new TextPointer((TextPointer)elementStart, startOffset);
ITextPointer end = (textRangeLength <= endOffset) ?
elementEnd.CreatePointer() : //new TextPointer((TextPointer)elementEnd) :
elementStart.CreatePointer(endOffset);// new TextPointer((TextPointer)elementStart, endOffset);
//we do not process 0 length selection
if (start.CompareTo(end) >= 0)
return null;
anchor.AddTextSegment(start, end);
}
//we do not support 0 or negative length selection
if (anchor.IsEmpty)
{
throw new ArgumentException(SR.Get(SRID.IncorrectAnchorLength), "locatorPart");
}
attachmentLevel = AttachmentLevel.Full;
if (_clamping)
{
ITextPointer currentStart = anchor.Start;
ITextPointer currentEnd = anchor.End;
IServiceProvider serviceProvider = null;
ITextView textView = null;
if (_targetPage != null)
{
serviceProvider = _targetPage as IServiceProvider;
}
else
{
FlowDocument content = currentStart.TextContainer.Parent as FlowDocument;
serviceProvider = PathNode.GetParent(content as DependencyObject) as IServiceProvider;
}
Invariant.Assert(serviceProvider != null, "No ServiceProvider found to get TextView from.");
textView = serviceProvider.GetService(typeof(ITextView)) as ITextView;
Invariant.Assert(textView != null, "Null TextView provided by ServiceProvider.");
anchor = TextAnchor.TrimToIntersectionWith(anchor, textView.TextSegments);
if (anchor == null)
{
attachmentLevel = AttachmentLevel.Unresolved;
}
else
{
if (anchor.Start.CompareTo(currentStart) != 0)
{
attachmentLevel &= ~AttachmentLevel.StartPortion;
}
if (anchor.End.CompareTo(currentEnd) != 0)
{
attachmentLevel &= ~AttachmentLevel.EndPortion;
}
}
}
return anchor;
}
/// <summary>
/// Creates a TextRange object spanning the portion of 'startNode'
/// specified by 'locatorPart'.
/// </summary>
/// <param name="locatorPart">FixedTextRange locator part specifying start and end point of
/// the TextRange</param>
/// <param name="startNode">the FixedPage containing this locator part</param>
/// <param name="attachmentLevel">set to AttachmentLevel.Full if the FixedPage for the locator
/// part was found, AttachmentLevel.Unresolved otherwise</param>
/// <returns>a TextRange spanning the text between start end end point in the FixedTextRange
/// locator part
/// , null if selection described by locator part could not be
/// recreated</returns>
/// <exception cref="ArgumentNullException">locatorPart or startNode are
/// null</exception>
/// <exception cref="ArgumentException">locatorPart is of the incorrect type</exception>
/// <exception cref="ArgumentException">startNode is not a FixedPage</exception>
/// <exception cref="ArgumentException">startNode does not belong to the DocumentViewer</exception>
public override Object ResolveLocatorPart(ContentLocatorPart locatorPart, DependencyObject startNode, out AttachmentLevel attachmentLevel)
{
if (startNode == null)
throw new ArgumentNullException("startNode");
DocumentPage docPage = null;
FixedPage page = startNode as FixedPage;
if (page != null)
{
docPage = GetDocumentPage(page);
}
else
{
// If we were passed a DPV because we are walking the visual tree,
// extract the DocumentPage from it; its TextView will be used to
// turn coordinates into text positions
DocumentPageView dpv = startNode as DocumentPageView;
if (dpv != null)
{
docPage = dpv.DocumentPage as FixedDocumentPage;
if (docPage == null)
{
docPage = dpv.DocumentPage as FixedDocumentSequenceDocumentPage;
}
}
}
if (docPage == null)
{
throw new ArgumentException(SR.Get(SRID.StartNodeMustBeDocumentPageViewOrFixedPage), "startNode");
}
if (locatorPart == null)
throw new ArgumentNullException("locatorPart");
attachmentLevel = AttachmentLevel.Unresolved;
ITextView tv = (ITextView)((IServiceProvider)docPage).GetService(typeof(ITextView));
Debug.Assert(tv != null);
ReadOnlyCollection<TextSegment> ts = tv.TextSegments;
//check first if a TextRange can be generated
if (ts == null || ts.Count <= 0)
return null;
TextAnchor resolvedAnchor = new TextAnchor();
if (docPage != null)
{
string stringCount = locatorPart.NameValuePairs["Count"];
if (stringCount == null)
throw new ArgumentException(SR.Get(SRID.InvalidLocatorPart, TextSelectionProcessor.CountAttribute));
int count = Int32.Parse(stringCount, NumberFormatInfo.InvariantInfo);
for(int i = 0; i < count; i++)
{
// First we extract the start and end Point from the locator part.
Point start;
Point end;
GetLocatorPartSegmentValues(locatorPart, i, out start, out end);
//calulate start ITextPointer
ITextPointer segStart;
if (double.IsNaN(start.X) || double.IsNaN(start.Y))
{
//get start of the page
segStart = FindStartVisibleTextPointer(docPage);
}
else
{
//convert Point to TextPointer
segStart = tv.GetTextPositionFromPoint(start, true);
}
if (segStart == null)
{
//selStart can be null if there are no insertion points on this page
continue;
}
//calulate end ITextPointer
ITextPointer segEnd;
if (double.IsNaN(end.X) || double.IsNaN(end.Y))
{
segEnd = FindEndVisibleTextPointer(docPage);
}
else
{
//convert Point to TextPointer
segEnd = tv.GetTextPositionFromPoint(end, true);
}
//end TP can not be null when start is not
Invariant.Assert(segEnd != null, "end TP is null when start TP is not");
attachmentLevel = AttachmentLevel.Full; // Not always true right?
resolvedAnchor.AddTextSegment(segStart, segEnd);
}
}
if (resolvedAnchor.TextSegments.Count > 0)
return resolvedAnchor;
else
return null;
}
/// <summary>
/// Merges highlights with the same color. Splits highlights with different colors
/// </summary>
/// <param name="service">the AnnotationService</param>
/// <param name="textRange">TextRange of the new highlight</param>
/// <param name="color">highlight color</param>
/// <param name="author">highlight author</param>
/// <param name="create">if true, this is create highlight operation, otherwise it is Clear</param>
/// <returns>the annotation created, if create flag was true; null otherwise</returns>
private static Annotation ProcessHighlights(AnnotationService service, ITextRange textRange, string author, Nullable<Color> color, bool create)
{
Invariant.Assert(textRange != null, "Parameter 'textRange' is null.");
IList<IAttachedAnnotation> spannedAnnots = GetSpannedAnnotations(service);
// Step one: trim all the spanned annotations so there is no overlap with the new annotation
foreach (IAttachedAnnotation attachedAnnotation in spannedAnnots)
{
if (HighlightComponent.TypeName.Equals(attachedAnnotation.Annotation.AnnotationType))
{
TextAnchor textAnchor = attachedAnnotation.FullyAttachedAnchor as TextAnchor;
Invariant.Assert(textAnchor != null, "FullyAttachedAnchor must not be null.");
TextAnchor copy = new TextAnchor(textAnchor);
// This modifies the current fully resolved anchor
copy = TextAnchor.TrimToRelativeComplement(copy, textRange.TextSegments);
// If the trimming resulting in no more content being in the anchor,
// delete the annotation
if (copy == null || copy.IsEmpty)
{
service.Store.DeleteAnnotation(attachedAnnotation.Annotation.Id);
continue;
}
// If there was some portion of content still in the anchor,
// generate new locators representing the modified anchor
SetAnchor(service, attachedAnnotation.Annotation, copy);
}
}
// Step two: create new annotation
if (create)
{
//create one annotation and return
Annotation highlight = CreateHighlight(service, textRange, author, color);
service.Store.AddAnnotation(highlight);
return highlight;
}
return null;
}
/// <summary>
/// Process the case of Empty selection for the different annotation types
/// </summary>
/// <param name="selection">the selection</param>
/// <param name="anchor">annotation anchor</param>
/// <param name="type">annotation type</param>
/// <returns></returns>
private static bool CheckCaret(ITextSelection selection, TextAnchor anchor, XmlQualifiedName type)
{
//selection must be empty
if (!selection.IsEmpty)
return false;
if (((anchor.Start.CompareTo(selection.Start) == 0) &&
(selection.Start.LogicalDirection == LogicalDirection.Forward)) ||
((anchor.End.CompareTo(selection.End) == 0) &&
(selection.End.LogicalDirection == LogicalDirection.Backward)))
return true;
return false;
}
/// <summary>
/// Modifies the text anchor's TextSegments so all of them
/// overlap with the passed in text segments. This is used
/// for instance to clamp a TextAnchor to a set of visible
/// text segments. If after trimming the anchor has no more
/// segments, null is returned instead. Callers should
/// assign the result of this method to the anchor they
/// passed in.
/// </summary>
/// <remarks>
/// Note: This method assumes textSegments is ordered and do not overlap amongs themselves
///
/// The target of the method is to trim this anchor's segments to overlap with the passed in segments.
/// The loop handles the following three cases -
/// 1. Current segment is after other segment, the other segment doesn't contribute at all, we move to the next other segment
/// 2. Current segment is before other segment, no overlap, remove current segment
/// 3. Current segment starts before other segment, and ends after other segment begins,
/// therefore the portion from current's start to other's start should be trimmed
/// 4. Current segment starts in the middle of other segment, two possibilities
/// a. current segment is completely within other segment, the whole segment overlaps
/// so we move on to the next current segment
/// b. current segment ends after other segment ends, we split current into the
/// overlapped portion and the remainder which will be looked at separately
/// </remarks>
/// <param name="anchor">the anchor to trim</param>
/// <param name="textSegments">collection of text segments to intersect with</param>
internal static TextAnchor TrimToIntersectionWith(TextAnchor anchor, ICollection <TextSegment> textSegments)
{
Invariant.Assert(anchor != null, "Anchor must not be null.");
Invariant.Assert(textSegments != null, "TextSegments must not be null.");
textSegments = SortTextSegments(textSegments, true);
TextSegment currentSegment, otherSegment = TextSegment.Null;
int current = 0;
IEnumerator <TextSegment> enumerator = textSegments.GetEnumerator();
bool hasMore = enumerator.MoveNext();
while (current < anchor._segments.Count && hasMore)
{
Invariant.Assert(otherSegment.Equals(TextSegment.Null) || otherSegment.Equals(enumerator.Current) || otherSegment.End.CompareTo(enumerator.Current.Start) <= 0, "TextSegments are overlapping or not ordered.");
currentSegment = anchor._segments[current];
otherSegment = enumerator.Current;
// Current segment is after other segment, so try the next other segment
if (currentSegment.Start.CompareTo(otherSegment.End) >= 0)
{
hasMore = enumerator.MoveNext(); // point to the next other
continue; // Do not increment, we are still on the same current
}
// Current segment is before other segment, no overlap so remove it and continue
if (currentSegment.End.CompareTo(otherSegment.Start) <= 0)
{
anchor._segments.RemoveAt(current);
continue; // Do not increment, it happens implicitly because of the remove
}
//
// We know from here down that there is some overlap.
//
// Current starts before the other segment and ends after other segment begins, the first portion of current segment doesn't overlap so we remove it
if (currentSegment.Start.CompareTo(otherSegment.Start) < 0)
{
anchor._segments[current] = CreateNormalizedSegment(otherSegment.Start, currentSegment.End);
continue; // Do not increment, we need to look at this just created segment
}
// Current segment begins in the middle of other segment...
else
{
// and ends after other segment does, we split current into the portion that is overlapping and the remainder
if (currentSegment.End.CompareTo(otherSegment.End) > 0)
{
anchor._segments[current] = CreateNormalizedSegment(currentSegment.Start, otherSegment.End);
// This segment will be the first one looked at next
anchor._segments.Insert(current + 1, CreateNormalizedSegment(otherSegment.End, currentSegment.End));
hasMore = enumerator.MoveNext();
}
// and ends at the same place as other segment, its completely overlapping, we move on to the next other
else if (currentSegment.End.CompareTo(otherSegment.End) == 0)
{
hasMore = enumerator.MoveNext();
}
// and ends within other segment, its completely overlapping, but we aren't done with other so we just continue
}
current++;
}
// If we finished and there are no more other segments, then any remaining segments
// in our list must not overlap, so we remove them.
if (!hasMore && current < anchor._segments.Count)
{
anchor._segments.RemoveRange(current, anchor._segments.Count - current);
}
if (anchor._segments.Count == 0)
{
return(null);
}
else
{
return(anchor);
}
}
/// <summary>
/// Modifies the passed in TextAnchor to contain its relative
/// complement to the set of text segments passed in. The resulting
/// TextAnchor contains those segments or portions of segments that do
/// not overlap with the passed in segments in anyway. If after trimming
/// the anchor has no more segments, null is returned instead. Callers
/// should assign the result of this method to the anchor they passed in.
/// </summary>
/// <param name="anchor">the anchor to trim</param>
/// <param name="textSegments">the text segments to calculate relative complement with</param>
/// <remarks>Note: textSegments is expected to be ordered and contain no overlapping segments</remarks>
internal static TextAnchor TrimToRelativeComplement(TextAnchor anchor, ICollection <TextSegment> textSegments)
{
Invariant.Assert(anchor != null, "Anchor must not be null.");
Invariant.Assert(textSegments != null, "TextSegments must not be null.");
textSegments = SortTextSegments(textSegments, true);
IEnumerator <TextSegment> enumerator = textSegments.GetEnumerator();
bool hasMore = enumerator.MoveNext();
int currentIndex = 0;
TextSegment current;
TextSegment otherSegment = TextSegment.Null;
while (currentIndex < anchor._segments.Count && hasMore)
{
Invariant.Assert(otherSegment.Equals(TextSegment.Null) || otherSegment.Equals(enumerator.Current) || otherSegment.End.CompareTo(enumerator.Current.Start) <= 0, "TextSegments are overlapping or not ordered.");
current = anchor._segments[currentIndex];
otherSegment = enumerator.Current;
// Current segment is after other segment, no overlap
// Also, done with the other segment, move to the next one
if (current.Start.CompareTo(otherSegment.End) >= 0)
{
hasMore = enumerator.MoveNext();
continue; // No increment, still processing the current segment
}
// Current segment starts after other segment starts and ...
if (current.Start.CompareTo(otherSegment.Start) >= 0)
{
// ends before other segment ends, complete overlap, remove the segment
if (current.End.CompareTo(otherSegment.End) <= 0)
{
anchor._segments.RemoveAt(currentIndex);
continue; // No increment, happens implicitly because of the removal
}
else
{
// ends after other segment, first portion of current overlaps,
// create new segment from end of other segment to end of current
anchor._segments[currentIndex] = CreateNormalizedSegment(otherSegment.End, current.End);
// Done with the other segment, move to the next one
hasMore = enumerator.MoveNext();
continue; // No increment, need to process just created segment
}
}
// Current segment starts before other segment starts and ...
else
{
// ends after it starts, first portion of current does not overlap,
// create new segment for that portion
if (current.End.CompareTo(otherSegment.Start) > 0)
{
anchor._segments[currentIndex] = CreateNormalizedSegment(current.Start, otherSegment.Start);
// If there's any portion of current after other segment, create a new segment for that which
// will be the next one processed
if (current.End.CompareTo(otherSegment.End) > 0)
{
// Overlap ends before current segment's end, we create a new segment with the remainder of current segment
anchor._segments.Insert(currentIndex + 1, CreateNormalizedSegment(otherSegment.End, current.End));
// Done with the other segment, move to the next one
hasMore = enumerator.MoveNext();
}
}
// ends before it starts, current is completely before other, no overlap, do nothing
}
currentIndex++;
}
if (anchor._segments.Count > 0)
{
return(anchor);
}
else
{
return(null);
}
}
