/// <summary>
/// Calculate tab offsets by going up
/// </summary>
private void CalculateTabOffsetUp(ITextSnapshotLine curLine, int colNumber, ColumnSizeInfo colTabOffset)
{
int curLineNumber = curLine.LineNumber - 1;
ITextSnapshot textSnapshot = _textView.TextSnapshot;
ElasticTabstopsLine elasticLine = _elasticTabstopsLinesCache[curLine.LineNumber];
bool isLastColumnInLine = elasticLine.IsLastColumnInLine(colNumber);
while (curLineNumber >= 0)
{
ITextSnapshotLine upLine = textSnapshot.GetLineFromLineNumber(curLineNumber);
ElasticTabstopsLine upElasticLine = GetElasticTabstopsLine(upLine);
if (upElasticLine.IsLastColumnInLine(colNumber) != isLastColumnInLine)
{
break;
}
ElasticTabstopsColumn upColumn = upElasticLine.GetColumnOrDefault(colNumber);
if (upColumn == null)
{
break;
}
upColumn.TabOffset = colTabOffset;
ShrinkTabOffset(upElasticLine, colNumber);
curLineNumber--;
}
}
/// <summary>
/// Calculate tab offsets by going down
/// </summary>
private void CalculateTabOffsetDown(ITextSnapshotLine curLine, int colNumber, ColumnSizeInfo colTabOffset)
{
int curLineNumber = curLine.LineNumber + 1;
ITextSnapshot textSnapshot = _textView.TextSnapshot;
ElasticTabstopsLine elasticLine = _elasticTabstopsLinesCache[curLine.LineNumber];
bool isLastColumnInLine = elasticLine.IsLastColumnInLine(colNumber);
while (curLineNumber < textSnapshot.LineCount)
{
ITextSnapshotLine downLine = textSnapshot.GetLineFromLineNumber(curLineNumber);
ElasticTabstopsLine downElasticLine = GetElasticTabstopsLine(downLine);
if (downElasticLine.IsLastColumnInLine(colNumber) != isLastColumnInLine)
{
break;
}
ElasticTabstopsColumn downColumn = downElasticLine.GetColumnOrDefault(colNumber);
if (downColumn == null)
{
break;
}
downColumn.TabOffset = colTabOffset;
ShrinkTabOffset(downElasticLine, colNumber);
curLineNumber++;
}
}
/// <summary>
/// Fix tab offset for a column if needed
/// </summary>
private void ShrinkTabOffset(ElasticTabstopsLine tabLine, int colNumber)
{
ElasticTabstopsColumn colTabOffset = tabLine.ElasticColumns[colNumber];
double width = CalculateInitialWidth(tabLine, colNumber);
if (colTabOffset.TabOffset.ColumnWidth < width)
{
colTabOffset.TabOffset.ColumnWidth = width;
colTabOffset.TabOffset.TabOffset = CalculateInitialTabOffset(tabLine, colNumber);
}
}
/// <summary>
/// Returns true if current line offsets changed regarding to given line
/// false otherwise
/// </summary>
internal bool ChangedRegardingTo(ElasticTabstopsLine oldLine)
{
if (ElasticColumns == oldLine.ElasticColumns)
{
return(false);
}
if (ElasticColumns.Length != oldLine.ElasticColumns.Length)
{
return(true);
}
return(ElasticColumns.Where((etc, i) => etc.ChangedRegardingTo(oldLine.ElasticColumns[i])).Any());
}
/// <summary>
/// Calculates column width for a specific column in specific line
/// </summary>
private double CalculateInitialWidth(ElasticTabstopsLine elasticLine, int colNumber)
{
ITextSnapshot textSnapshot = _textView.TextSnapshot;
ElasticTabstopsColumn column = elasticLine.ElasticColumns[colNumber];
Span span = new Span(column.Start, column.ColumnTextLength);
if (span.Start > textSnapshot.Length || span.End > textSnapshot.Length)
{
return(0);
}
SnapshotSpan columnSpan = new SnapshotSpan(textSnapshot, span);
double columnWidth = _textMeasureService.GetWidth(columnSpan);
return(Math.Max(columnWidth, _minCellWidth));
}
/// <summary>
/// Calculate tab offsets for line in a given direction
/// </summary>
private void CalculateTabOffsets(ITextSnapshotLine line, CalculateDirection direction, bool forceInvalidate)
{
//Calculates tab offset for a given line for the given direction
ElasticTabstopsLine elasticLine = GetElasticTabstopsLine(line, forceInvalidate);
for (int colNumber = 0; colNumber < elasticLine.ElasticColumns.Length; colNumber++)
{
ElasticTabstopsColumn column = elasticLine.ElasticColumns[colNumber];
//Tab offset is allready calculated during other line calculation
if (!forceInvalidate && column.TabOffset != null)
{
continue;
}
//Assign the same ColumnTabOffset to all columns in the same block
ColumnSizeInfo colTabOffset = new ColumnSizeInfo
{
TabOffset = CalculateInitialTabOffset(elasticLine, colNumber),
ColumnWidth = CalculateInitialWidth(elasticLine, colNumber)
};
column.TabOffset = colTabOffset;
switch (direction)
{
case CalculateDirection.Up:
CalculateTabOffsetUp(line, colNumber, colTabOffset);
break;
case CalculateDirection.Down:
CalculateTabOffsetDown(line, colNumber, colTabOffset);
break;
case CalculateDirection.DownUp:
CalculateTabOffsetDown(line, colNumber, colTabOffset);
CalculateTabOffsetUp(line, colNumber, colTabOffset);
break;
default:
throw new ArgumentException("direction");
}
}
}
/// <summary>
/// Returns ElasticTabstopsLine with initialized ElasticColumns
/// </summary>
private ElasticTabstopsLine GetElasticTabstopsLine(ITextSnapshotLine line, bool forceInvalidateColumns = false)
{
ElasticTabstopsLine elasticTabstopsLine = _elasticTabstopsLinesCache[line.LineNumber];
if (elasticTabstopsLine.ElasticColumns == null || forceInvalidateColumns)
{
string lineText = line.GetText();
string[] tabSplits = lineText.Split('\t');
elasticTabstopsLine.ElasticColumns = new ElasticTabstopsColumn[tabSplits.Length];
int curPosInLine = line.Start.Position;
for (int i = 0; i < tabSplits.Length; i++)
{
string ts = tabSplits[i];
ElasticTabstopsColumn column = new ElasticTabstopsColumn {
ColumnTextLength = ts.Length, Start = curPosInLine
};
//skeep tab
curPosInLine += ts.Length + 1;
elasticTabstopsLine.ElasticColumns[i] = column;
}
}
return(elasticTabstopsLine);
}
/// <summary>
/// Calulates tab offset depending column widthes before current column
/// This method assume that column widthes before current column are calculated allready
/// </summary>
private double CalculateInitialTabOffset(ElasticTabstopsLine tabLine, int colNumber)
{
return(tabLine.ElasticColumns.Take(colNumber).Sum(ct => ct.TabOffset.ColumnWidth) + colNumber * _paddingWidth);
}
/// <summary>
/// Invalidates tabs cache depending given changes, and return changed line numbers
/// </summary>
/// <param name="changes">changed made</param>
internal void InvalidateChanges(INormalizedTextChangeCollection changes)
{
if (!changes.Any())
{
return;
}
#region Old
var firstChange = changes.First();
var start = Math.Min(firstChange.OldSpan.Start, firstChange.NewSpan.Start);
var end = Math.Max(firstChange.OldSpan.End, firstChange.NewSpan.End);
foreach (var change in changes)
{
var lineNumber = _textView.TextSnapshot.GetLineNumberFromPosition(change.NewPosition);
if (change.LineCountDelta > 0)
{
_elasticTabstopsLinesCache.InsertRange(lineNumber,
Enumerable.Range(0, change.LineCountDelta).Select(
c => new ElasticTabstopsLine()));
}
else if (change.LineCountDelta < 0)
{
_elasticTabstopsLinesCache.RemoveRange(lineNumber, -change.LineCountDelta);
}
start = Math.Min(start, Math.Min(change.OldSpan.Start, change.NewSpan.Start));
end = Math.Max(end, Math.Max(change.OldSpan.End, change.NewSpan.End));
}
var topLine = _textView.TextSnapshot.GetLineFromPosition(start);
var topLineNumber = topLine.LineNumber;
if (changes.IncludesLineChanges && topLineNumber != 0)
{
topLineNumber--;
topLine = _textView.TextSnapshot.GetLineFromLineNumber(topLineNumber);
}
while (topLineNumber > 0 &&
topLine.Start != topLine.End)
{
topLineNumber--;
topLine = _textView.TextSnapshot.GetLineFromLineNumber(topLineNumber);
}
end = Math.Min(end, Math.Max(0, _textView.TextSnapshot.Length - 1));
var bottomLine = _textView.TextSnapshot.GetLineFromPosition(end);
var bottomLineNumber = bottomLine.LineNumber;
if (changes.IncludesLineChanges && bottomLineNumber < _textView.TextSnapshot.LineCount - 1)
{
bottomLineNumber++;
bottomLine = _textView.TextSnapshot.GetLineFromLineNumber(bottomLineNumber);
}
while (bottomLineNumber < _textView.TextSnapshot.LineCount - 1 &&
bottomLine.Start != bottomLine.End)
{
bottomLineNumber++;
bottomLine = _textView.TextSnapshot.GetLineFromLineNumber(bottomLineNumber);
}
#endregion
//InvalidateChanges();
for (var i = topLineNumber; i <= bottomLineNumber; i++)
{
_elasticTabstopsLinesCache[i] = new ElasticTabstopsLine();
}
for (var i = topLineNumber; i <= bottomLineNumber; i++)
{
var line = _textView.TextSnapshot.GetLineFromLineNumber(i);
CalculateTabOffsets(line, CalculateDirection.Down, false);
}
}
