static TextViewPosition GetPrevCaretPosition(TextView textView, TextViewPosition caretPosition, VisualLine visualLine, CaretPositioningMode mode, bool enableVirtualSpace)
{
int pos = visualLine.GetNextCaretPosition(caretPosition.VisualColumn, LogicalDirection.Backward, mode, enableVirtualSpace);
if (pos >= 0)
{
return(visualLine.GetTextViewPosition(pos));
}
else
{
// move to end of previous line
DocumentLine previousDocumentLine = visualLine.FirstDocumentLine.PreviousLine;
if (previousDocumentLine != null)
{
VisualLine previousLine = textView.GetOrConstructVisualLine(previousDocumentLine);
pos = previousLine.GetNextCaretPosition(previousLine.VisualLength + 1, LogicalDirection.Backward, mode, enableVirtualSpace);
if (pos < 0)
{
throw ThrowUtil.NoValidCaretPosition();
}
return(previousLine.GetTextViewPosition(pos));
}
else
{
// at start of document
Debug.Assert(visualLine.FirstDocumentLine.Offset == 0);
return(new TextViewPosition(0, 0));
}
}
}
static TextViewPosition GetNextCaretPosition(TextView textView, TextViewPosition caretPosition, VisualLine visualLine, CaretPositioningMode mode, bool enableVirtualSpace)
{
int pos = visualLine.GetNextCaretPosition(caretPosition.VisualColumn, LogicalDirection.Forward, mode, enableVirtualSpace);
if (pos >= 0)
{
return(visualLine.GetTextViewPosition(pos));
}
else
{
// move to start of next line
DocumentLine nextDocumentLine = visualLine.LastDocumentLine.NextLine;
if (nextDocumentLine != null)
{
VisualLine nextLine = textView.GetOrConstructVisualLine(nextDocumentLine);
pos = nextLine.GetNextCaretPosition(-1, LogicalDirection.Forward, mode, enableVirtualSpace);
if (pos < 0)
{
throw ThrowUtil.NoValidCaretPosition();
}
return(nextLine.GetTextViewPosition(pos));
}
else
{
// at end of document
Debug.Assert(visualLine.LastDocumentLine.Offset + visualLine.LastDocumentLine.TotalLength == textView.Document.TextLength);
return(new TextViewPosition(textView.Document.GetLocation(textView.Document.TextLength)));
}
}
}
static TextViewPosition GetEndOfLineCaretPosition(VisualLine visualLine, TextLine textLine)
{
int newVC = visualLine.GetTextLineVisualStartColumn(textLine) + textLine.Length;
TextViewPosition pos = visualLine.GetTextViewPosition(newVC);
pos.IsAtEndOfLine = true;
return(pos);
}
private static TextViewPosition GetEndOfLineCaretPosition(VisualLine visualLine, TextLine textLine)
{
var newVisualCol = visualLine.GetTextLineVisualStartColumn(textLine) + textLine.Length - textLine.TrailingWhitespaceLength;
var pos = visualLine.GetTextViewPosition(newVisualCol);
pos.IsAtEndOfLine = true;
return(pos);
}
static TextViewPosition GetPrevCaretPosition(TextView textView, TextViewPosition caretPosition, VisualLine visualLine, CaretPositioningMode mode, bool enableVirtualSpace)
{
int pos = visualLine.GetNextCaretPosition(caretPosition.VisualColumn, LogicalDirection.Backward, mode, enableVirtualSpace);
if (pos >= 0)
{
return(visualLine.GetTextViewPosition(pos));
}
var previousDocumentLine = visualLine.FirstDocumentLine.PreviousLine;
if (previousDocumentLine != null)
{
var previousLine = textView.GetOrConstructVisualLine(previousDocumentLine);
pos = previousLine.GetNextCaretPosition(previousLine.VisualLength + 1, LogicalDirection.Backward, mode, enableVirtualSpace);
return(previousLine.GetTextViewPosition(pos));
}
return(new TextViewPosition(0, 0));
}
static TextViewPosition GetStartOfLineCaretPosition(int oldVC, VisualLine visualLine, TextLine textLine, bool enableVirtualSpace)
{
int newVC = visualLine.GetTextLineVisualStartColumn(textLine);
if (newVC == 0)
{
newVC = visualLine.GetNextCaretPosition(newVC - 1, LogicalDirection.Forward, CaretPositioningMode.WordStart, 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 == oldVC)
{
newVC = 0;
}
return(visualLine.GetTextViewPosition(newVC));
}
static TextViewPosition GetUpDownCaretPosition(TextView textView, TextViewPosition caretPosition, CaretMovementType direction, VisualLine visualLine, TextLine textLine, bool enableVirtualSpace, ref double xPos)
{
// moving up/down happens using the desired visual X position
if (double.IsNaN(xPos))
{
xPos = visualLine.GetTextLineVisualXPosition(textLine, caretPosition.VisualColumn);
}
// now find the TextLine+VisualLine where the caret will end up in
VisualLine targetVisualLine = visualLine;
TextLine targetLine;
int textLineIndex = visualLine.TextLines.IndexOf(textLine);
switch (direction)
{
case CaretMovementType.LineUp:
{
// Move up: move to the previous TextLine in the same visual line
// or move to the last TextLine of the previous visual line
int prevLineNumber = visualLine.FirstDocumentLine.LineNumber - 1;
if (textLineIndex > 0)
{
targetLine = visualLine.TextLines[textLineIndex - 1];
}
else if (prevLineNumber >= 1)
{
DocumentLine prevLine = textView.Document.GetLineByNumber(prevLineNumber);
targetVisualLine = textView.GetOrConstructVisualLine(prevLine);
targetLine = targetVisualLine.TextLines[targetVisualLine.TextLines.Count - 1];
}
else
{
targetLine = null;
}
break;
}
case CaretMovementType.LineDown:
{
// Move down: move to the next TextLine in the same visual line
// or move to the first TextLine of the next visual line
int nextLineNumber = visualLine.LastDocumentLine.LineNumber + 1;
if (textLineIndex < visualLine.TextLines.Count - 1)
{
targetLine = visualLine.TextLines[textLineIndex + 1];
}
else if (nextLineNumber <= textView.Document.LineCount)
{
DocumentLine nextLine = textView.Document.GetLineByNumber(nextLineNumber);
targetVisualLine = textView.GetOrConstructVisualLine(nextLine);
targetLine = targetVisualLine.TextLines[0];
}
else
{
targetLine = null;
}
break;
}
case CaretMovementType.PageUp:
case CaretMovementType.PageDown:
{
// Page up/down: find the target line using its visual position
double yPos = visualLine.GetTextLineVisualYPosition(textLine, VisualYPosition.LineMiddle);
if (direction == CaretMovementType.PageUp)
{
yPos -= textView.RenderSize.Height;
}
else
{
yPos += textView.RenderSize.Height;
}
DocumentLine newLine = textView.GetDocumentLineByVisualTop(yPos);
targetVisualLine = textView.GetOrConstructVisualLine(newLine);
targetLine = targetVisualLine.GetTextLineByVisualYPosition(yPos);
break;
}
default:
throw new NotSupportedException(direction.ToString());
}
if (targetLine != null)
{
double yPos = targetVisualLine.GetTextLineVisualYPosition(targetLine, VisualYPosition.LineMiddle);
int newVisualColumn = targetVisualLine.GetVisualColumn(new Point(xPos, yPos), enableVirtualSpace);
// prevent wrapping to the next line; TODO: could 'IsAtEnd' help here?
int targetLineStartCol = targetVisualLine.GetTextLineVisualStartColumn(targetLine);
if (newVisualColumn >= targetLineStartCol + targetLine.Length)
{
if (newVisualColumn <= targetVisualLine.VisualLength)
{
newVisualColumn = targetLineStartCol + targetLine.Length - 1;
}
}
return(targetVisualLine.GetTextViewPosition(newVisualColumn));
}
else
{
return(caretPosition);
}
}