public static CaretVector From(SourcePoint target, SourcePoint source, ElementPosition position)
{
CaretVector caretVector = new CaretVector(position);
caretVector.LineDelta = target.Line - source.Line;
caretVector.OffsetDelta = target.Offset - source.Offset;
return caretVector;
}
private SourcePoint GetSourcePoint(LanguageElement element, CaretVector vector)
{
if (element == null || vector == null)
return SourcePoint.Empty;
ICapableBlock iCapableBlock = null;
switch (vector.ElementPosition)
{
case ElementPosition.Start:
return GetPosition(element.Range.Start, vector);
case ElementPosition.End:
return GetPosition(element.Range.End, vector);
case ElementPosition.NameRangeStart:
return GetPosition(element.NameRange.Start, vector);
case ElementPosition.NameRangeEnd:
return GetPosition(element.NameRange.End, vector);
case ElementPosition.BlockBegin:
iCapableBlock = element as ICapableBlock;
if (iCapableBlock != null)
return GetPosition(iCapableBlock.BlockStart.End, vector);
else
return GetPosition(element.Range.Start, vector);
case ElementPosition.BlockEnd:
iCapableBlock = element as ICapableBlock;
if (iCapableBlock != null)
return GetPosition(iCapableBlock.BlockEnd.Start, vector);
else
return GetPosition(element.Range.End, vector);
case ElementPosition.FirstChildStart:
LanguageElement firstChild = element.FirstChild;
if (firstChild == null)
return SourcePoint.Empty;
return GetPosition(firstChild.Range.Start, vector);
case ElementPosition.LastChildEnd:
LanguageElement lastChild = element.LastChild;
if (lastChild == null)
return SourcePoint.Empty;
return GetPosition(lastChild.Range.End, vector);
case ElementPosition.FirstDetailStart:
LanguageElement firstDetail = element.FirstDetail;
if (firstDetail == null)
return SourcePoint.Empty;
return GetPosition(firstDetail.Range.Start, vector);
case ElementPosition.LastDetailEnd:
LanguageElement lastDetail = element.LastDetail;
if (lastDetail == null)
return SourcePoint.Empty;
return GetPosition(lastDetail.Range.End, vector);
}
throw new Exception("Unexpected ElementPosition enum element.");
}
private static SourcePoint GetPosition(SourcePoint sourcePoint, CaretVector vector)
{
return sourcePoint.OffsetPoint(vector.LineDelta, vector.OffsetDelta);
}