--- /dev/null
+package net.sourceforge.phpdt.internal.ui.text;
+
+/*
+ * (c) Copyright IBM Corp. 2000, 2001.
+ * All Rights Reserved.
+ */
+
+import java.io.IOException;
+
+import org.eclipse.jface.text.BadLocationException;
+import org.eclipse.jface.text.IDocument;
+import org.eclipse.jface.text.IRegion;
+import org.eclipse.jface.text.Region;
+
+/**
+ * Helper class for match pairs of characters.
+ */
+public class PHPPairMatcher {
+
+
+ public static final int LEFT= 1;
+ public static final int RIGHT= 2;
+
+
+ protected char[] fPairs;
+ protected IDocument fDocument;
+ protected int fOffset;
+
+ protected int fStartPos;
+ protected int fEndPos;
+ protected int fAnchor;
+
+ protected PHPCodeReader fReader= new PHPCodeReader();
+
+
+ public PHPPairMatcher(char[] pairs) {
+ fPairs= pairs;
+ }
+
+ public IRegion match(IDocument document, int offset) {
+
+ fOffset= offset;
+
+ if (fOffset < 0)
+ return null;
+
+ fDocument= document;
+
+ if (matchPairsAt() && fStartPos != fEndPos)
+ return new Region(fStartPos, fEndPos - fStartPos + 1);
+
+ return null;
+ }
+
+ public int getAnchor() {
+ return fAnchor;
+ }
+
+ public void dispose() {
+ fDocument= null;
+ if (fReader != null) {
+ try {
+ fReader.close();
+ } catch (IOException x) {
+ // ignore
+ }
+ fReader= null;
+ }
+ }
+
+ protected boolean matchPairsAt() {
+
+ int i;
+ int pairIndex1= fPairs.length;
+ int pairIndex2= fPairs.length;
+
+ fStartPos= -1;
+ fEndPos= -1;
+
+ // get the chars preceding and following the start position
+ try {
+
+ char prevChar= fDocument.getChar(Math.max(fOffset - 1, 0));
+ char nextChar= fDocument.getChar(fOffset);
+
+ // search for opening peer character next to the activation point
+ for (i= 0; i < fPairs.length; i= i + 2) {
+ if (nextChar == fPairs[i]) {
+ fStartPos= fOffset;
+ pairIndex1= i;
+ } else if (prevChar == fPairs[i]) {
+ fStartPos= fOffset - 1;
+ pairIndex1= i;
+ }
+ }
+
+ // search for closing peer character next to the activation point
+ for (i= 1; i < fPairs.length; i= i + 2) {
+ if (prevChar == fPairs[i]) {
+ fEndPos= fOffset - 1;
+ pairIndex2= i;
+ } else if (nextChar == fPairs[i]) {
+ fEndPos= fOffset;
+ pairIndex2= i;
+ }
+ }
+
+ if (fEndPos > -1) {
+ fAnchor= RIGHT;
+ fStartPos= searchForOpeningPeer(fEndPos, fPairs[pairIndex2 - 1], fPairs[pairIndex2], fDocument);
+ if (fStartPos > -1)
+ return true;
+ else
+ fEndPos= -1;
+ } else if (fStartPos > -1) {
+ fAnchor= LEFT;
+ fEndPos= searchForClosingPeer(fStartPos, fPairs[pairIndex1], fPairs[pairIndex1 + 1], fDocument);
+ if (fEndPos > -1)
+ return true;
+ else
+ fStartPos= -1;
+ }
+
+ } catch (BadLocationException x) {
+ } catch (IOException x) {
+ }
+
+ return false;
+ }
+
+ protected int searchForClosingPeer(int offset, int openingPeer, int closingPeer, IDocument document) throws IOException {
+
+ fReader.configureForwardReader(document, offset + 1, document.getLength(), true, true);
+
+ int stack= 1;
+ int c= fReader.read();
+ while (c != PHPCodeReader.EOF) {
+ if (c == openingPeer && c != closingPeer)
+ stack++;
+ else if (c == closingPeer)
+ stack--;
+
+ if (stack == 0)
+ return fReader.getOffset();
+
+ c= fReader.read();
+ }
+
+ return -1;
+ }
+
+ protected int searchForOpeningPeer(int offset, int openingPeer, int closingPeer, IDocument document) throws IOException {
+
+ fReader.configureBackwardReader(document, offset, true, true);
+
+ int stack= 1;
+ int c= fReader.read();
+ while (c != PHPCodeReader.EOF) {
+ if (c == closingPeer && c != openingPeer)
+ stack++;
+ else if (c == openingPeer)
+ stack--;
+
+ if (stack == 0)
+ return fReader.getOffset();
+
+ c= fReader.read();
+ }
+
+ return -1;
+ }
+}