/// <summary>
/// Validates the visual column of the caret using the specified visual line.
/// The visual line must contain the caret offset.
/// </summary>
void RevalidateVisualColumn(VisualLine visualLine)
{
if (visualLine == null)
throw new ArgumentNullException("visualLine");
// mark column as validated
visualColumnValid = true;
int caretOffset = textView.Document.GetOffset(position.Location);
int firstDocumentLineOffset = visualLine.FirstDocumentLine.Offset;
position.VisualColumn = visualLine.ValidateVisualColumn(position, textArea.Selection.EnableVirtualSpace);
// search possible caret positions
int newVisualColumnForwards = visualLine.GetNextCaretPosition(position.VisualColumn - 1, LogicalDirection.Forward, CaretPositioningMode.Normal, textArea.Selection.EnableVirtualSpace);
// If position.VisualColumn was valid, we're done with validation.
if (newVisualColumnForwards != position.VisualColumn) {
// also search backwards so that we can pick the better match
int newVisualColumnBackwards = visualLine.GetNextCaretPosition(position.VisualColumn + 1, LogicalDirection.Backward, CaretPositioningMode.Normal, textArea.Selection.EnableVirtualSpace);
if (newVisualColumnForwards < 0 && newVisualColumnBackwards < 0)
throw ThrowUtil.NoValidCaretPosition();
// determine offsets for new visual column positions
int newOffsetForwards;
if (newVisualColumnForwards >= 0)
newOffsetForwards = visualLine.GetRelativeOffset(newVisualColumnForwards) + firstDocumentLineOffset;
else
newOffsetForwards = -1;
int newOffsetBackwards;
if (newVisualColumnBackwards >= 0)
newOffsetBackwards = visualLine.GetRelativeOffset(newVisualColumnBackwards) + firstDocumentLineOffset;
else
newOffsetBackwards = -1;
int newVisualColumn, newOffset;
// if there's only one valid position, use it
if (newVisualColumnForwards < 0) {
newVisualColumn = newVisualColumnBackwards;
newOffset = newOffsetBackwards;
} else if (newVisualColumnBackwards < 0) {
newVisualColumn = newVisualColumnForwards;
newOffset = newOffsetForwards;
} else {
// two valid positions: find the better match
if (Math.Abs(newOffsetBackwards - caretOffset) < Math.Abs(newOffsetForwards - caretOffset)) {
// backwards is better
newVisualColumn = newVisualColumnBackwards;
newOffset = newOffsetBackwards;
} else {
// forwards is better
newVisualColumn = newVisualColumnForwards;
newOffset = newOffsetForwards;
}
}
this.Position = new TextViewPosition(textView.Document.GetLocation(newOffset), newVisualColumn);
}
isInVirtualSpace = (position.VisualColumn > visualLine.VisualLength);
}
static void SetCaretPosition(TextArea textArea, VisualLine targetVisualLine, TextLine targetLine,
int newVisualColumn, bool allowWrapToNextLine)
{
int targetLineStartCol = targetVisualLine.GetTextLineVisualStartColumn(targetLine);
if (!allowWrapToNextLine && newVisualColumn >= targetLineStartCol + targetLine.Length) {
if (newVisualColumn <= targetVisualLine.VisualLength)
newVisualColumn = targetLineStartCol + targetLine.Length - 1;
}
int newOffset = targetVisualLine.GetRelativeOffset(newVisualColumn) + targetVisualLine.FirstDocumentLine.Offset;
SetCaretPosition(textArea, newVisualColumn, newOffset);
}
static void MoveCaretToStartOfLine(TextArea textArea, VisualLine visualLine)
{
int newVC = visualLine.GetNextCaretPosition(-1, LogicalDirection.Forward, CaretPositioningMode.WordStart, textArea.Selection.EnableVirtualSpace);
if (newVC < 0)
throw ThrowUtil.NoValidCaretPosition();
// when the caret is already at the start of the text, jump to start before whitespace
if (newVC == textArea.Caret.VisualColumn)
newVC = 0;
int offset = visualLine.FirstDocumentLine.Offset + visualLine.GetRelativeOffset(newVC);
SetCaretPosition(textArea, newVC, offset);
}
static void MoveCaretToEndOfLine(TextArea textArea, VisualLine visualLine)
{
int newVC = visualLine.VisualLength;
int offset = visualLine.FirstDocumentLine.Offset + visualLine.GetRelativeOffset(newVC);
SetCaretPosition(textArea, newVC, offset);
}
static void MoveCaretRight(TextArea textArea, TextViewPosition caretPosition, VisualLine visualLine, CaretPositioningMode mode)
{
int pos = visualLine.GetNextCaretPosition(caretPosition.VisualColumn, LogicalDirection.Forward, mode, textArea.Selection.EnableVirtualSpace);
if (pos >= 0) {
SetCaretPosition(textArea, pos, visualLine.GetRelativeOffset(pos) + visualLine.FirstDocumentLine.Offset);
} else {
// move to start of next line
DocumentLine nextDocumentLine = visualLine.LastDocumentLine.NextLine;
if (nextDocumentLine != null) {
VisualLine nextLine = textArea.TextView.GetOrConstructVisualLine(nextDocumentLine);
pos = nextLine.GetNextCaretPosition(-1, LogicalDirection.Forward, mode, textArea.Selection.EnableVirtualSpace);
if (pos < 0)
throw ThrowUtil.NoValidCaretPosition();
SetCaretPosition(textArea, pos, nextLine.GetRelativeOffset(pos) + nextLine.FirstDocumentLine.Offset);
} else {
// at end of document
Debug.Assert(visualLine.LastDocumentLine.Offset + visualLine.LastDocumentLine.TotalLength == textArea.Document.TextLength);
SetCaretPosition(textArea, -1, textArea.Document.TextLength);
}
}
}
static void MoveCaretLeft(TextArea textArea, TextViewPosition caretPosition, VisualLine visualLine, CaretPositioningMode mode)
{
int pos = visualLine.GetNextCaretPosition(caretPosition.VisualColumn, LogicalDirection.Backward, mode, textArea.Selection.EnableVirtualSpace);
if (pos >= 0) {
SetCaretPosition(textArea, pos, visualLine.GetRelativeOffset(pos) + visualLine.FirstDocumentLine.Offset);
} else {
// move to end of previous line
DocumentLine previousDocumentLine = visualLine.FirstDocumentLine.PreviousLine;
if (previousDocumentLine != null) {
VisualLine previousLine = textArea.TextView.GetOrConstructVisualLine(previousDocumentLine);
pos = previousLine.GetNextCaretPosition(previousLine.VisualLength + 1, LogicalDirection.Backward, mode, textArea.Selection.EnableVirtualSpace);
if (pos < 0)
throw ThrowUtil.NoValidCaretPosition();
SetCaretPosition(textArea, pos, previousLine.GetRelativeOffset(pos) + previousLine.FirstDocumentLine.Offset);
} else {
// at start of document
Debug.Assert(visualLine.FirstDocumentLine.Offset == 0);
SetCaretPosition(textArea, 0, 0);
}
}
}