internal static bool Intersects(TextSpan span1, TextSpan span2)
{
return(TextSpanHelper.StartsBeforeEndOf(span1, span2) &&
TextSpanHelper.EndsAfterStartOf(span1, span2));
}
const int ChunkThreshold = 1000; // don't combine chunks separate by more than 1000 characters.
ArrayList MergeEdits(ArrayList edits)
{
StringBuilder buffer = new StringBuilder();
EditSpan combined = null;
ArrayList merged = new ArrayList();
ArrayList markers = GetTextMarkers();
int markerPos = 0;
TextSpan marker = (markers.Count > 0) ? (TextSpan)markers[0] : new TextSpan();
foreach (EditSpan editSpan in edits)
{
TextSpan span = editSpan.Span;
string text = editSpan.Text;
if (markerPos < markers.Count &&
(TextSpanHelper.StartsAfterStartOf(span, marker) || TextSpanHelper.EndsAfterStartOf(span, marker)))
{
AddCombinedEdit(combined, buffer, merged);
if (TextSpanHelper.Intersects(span, marker))
{
combined = null;
// Have to apply this as a distinct edit operation.
merged.Add(editSpan);
}
else
{
combined = editSpan;
buffer.Append(text);
}
while (++markerPos < markers.Count)
{
marker = (TextSpan)markers[markerPos];
if (!TextSpanHelper.StartsAfterStartOf(span, marker) && !TextSpanHelper.EndsAfterStartOf(span, marker))
{
break;
}
}
}
else if (combined == null)
{
combined = editSpan;
buffer.Append(text);
}
else
{
// A little sanity check here, if there are too many characters in between the two
// edits, then keep them separate.
int startOffset = source.GetPositionOfLineIndex(combined.Span.iEndLine, combined.Span.iEndIndex);
int endOffset = source.GetPositionOfLineIndex(span.iStartLine, span.iStartIndex);
if (endOffset - startOffset > ChunkThreshold)
{
AddCombinedEdit(combined, buffer, merged);
combined = editSpan;
buffer.Append(text);
}
else
{
// merge edit spans by adding the text in-between the current and previous spans.
TextSpan s = combined.Span;
string between = this.source.GetText(s.iEndLine, s.iEndIndex, span.iStartLine, span.iStartIndex);
buffer.Append(between);
buffer.Append(text); // and add the new text.
s.iEndIndex = span.iEndIndex;
s.iEndLine = span.iEndLine;
combined.Span = s;
}
}
}
AddCombinedEdit(combined, buffer, merged);
return(merged);
}
