void drawLine(int lno) {
   if (lno < 0 || lno >= text.getLineCount()) return;
   int y = text.getLocationAtOffset(text.getOffsetAtLine(lno)).y;
   int height = 0;
   if (text.getLineCount() > lno + 1)
     height = text.getLocationAtOffset(text.getOffsetAtLine(lno + 1)).y - y;
   else height = text.getLocationAtOffset(text.getCharCount()).y + text.getLineHeight();
   int width = text.getClientArea().width + text.getHorizontalPixel();
   text.redraw(0, y, width, height, false);
 }
 /** Moves caret to the position of currently active pair. */
 public boolean matchPair() {
   if (currentPair == null) return false;
   int caret = text.getCaretOffset();
   int lno = text.getLineAtOffset(caret);
   PairMatch cp = baseEditor.getPairMatch(lno, caret - text.getOffsetAtLine(lno));
   baseEditor.searchGlobalPair(cp);
   if (cp.end == null) return false;
   if (cp.topPosition) text.setSelection(text.getOffsetAtLine(cp.eline) + cp.end.end);
   else text.setSelection(text.getOffsetAtLine(cp.eline) + cp.end.start);
   return true;
 }
 void pairsDraw(GC gc, PairMatch pm) {
   if (pm == null) return;
   if (pm.start != null) {
     if (pm.sline >= text.getLineCount()) return;
     int lineOffset = text.getOffsetAtLine(pm.sline);
     pairDraw(
         gc, (StyledRegion) pm.start.rdef, pm.start.start + lineOffset, pm.start.end + lineOffset);
   }
   if (pm.end != null) {
     if (pm.eline >= text.getLineCount()) return;
     int lineOffset = text.getOffsetAtLine(pm.eline);
     pairDraw(gc, (StyledRegion) pm.end.rdef, pm.end.start + lineOffset, pm.end.end + lineOffset);
   }
 }
 void redrawFrom(int lno) {
   if (lno < 0 || lno >= text.getLineCount()) return;
   int y = text.getLocationAtOffset(text.getOffsetAtLine(lno)).y;
   int height = text.getClientArea().height - y;
   int width = text.getClientArea().width + text.getHorizontalPixel();
   text.redraw(0, y, width, height, false);
 }
 public void stateChanged() {
   backParserDelay = true;
   int curLine = text.getLineAtOffset(text.getCaretOffset());
   if (lineHighlighting && text.getSelectionRange().y != 0) {
     lineHighlighting = false;
     drawLine(prevLine);
     pairsHighlighting = false;
     pairsDraw(null, currentPair);
     return;
   }
   if (text.getSelectionRange().y != 0) return;
   if (!lineHighlighting) {
     // drawing current line
     lineHighlighting = true;
     drawLine(curLine);
   } else if (curLine != prevLine) {
     drawLine(prevLine);
     drawLine(curLine);
     prevLine = curLine;
   }
   // drawing current pairs
   if (!pairsHighlighting) {
     pairsHighlighting = true;
     pairsDraw(null, currentPair);
   } else {
     int lineOffset = text.getOffsetAtLine(curLine);
     PairMatch newmatch = baseEditor.getPairMatch(curLine, text.getCaretOffset() - lineOffset);
     if (newmatch != null) baseEditor.searchLocalPair(newmatch);
     if ((newmatch == null && currentPair != null)
         || (newmatch != null && !newmatch.equals(currentPair))) {
       pairsDraw(null, currentPair);
       pairsDraw(null, newmatch);
     }
     currentPair = newmatch;
   }
 }