/*******************************************************************************
* Copyright (c) 2009 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
* Zend Technologies
*******************************************************************************/
package org.eclipse.php.internal.ui.editor;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.Region;
import org.eclipse.jface.text.source.ICharacterPairMatcher;
import org.eclipse.php.internal.core.format.PHPHeuristicScanner;
import org.eclipse.php.internal.core.format.Symbols;
/**
* Helper class for match pairs of characters. (Formerly used WTP's
* JavePairMatcher)
*/
public final class PHPPairMatcher implements ICharacterPairMatcher {
private char[] fPairs;
private IDocument fDocument;
private int fOffset;
private int fStartPos;
private int fEndPos;
private int fAnchor;
/**
* Stores the source version state.
*
* @since 3.1
*/
private boolean fHighlightAngularBrackets = false;
public PHPPairMatcher(char[] pairs) {
fPairs = pairs;
}
@Override
public IRegion match(IDocument document, int offset) {
fOffset = offset;
if (fOffset < 0) {
return null;
}
fDocument = document;
if (fDocument != null && matchPairsAt() && fStartPos != fEndPos) {
return new Region(fStartPos, fEndPos - fStartPos + 1);
}
return null;
}
/**
* @see org.eclipse.jface.text.source.ICharacterPairMatcher#getAnchor()
*/
@Override
public int getAnchor() {
return fAnchor;
}
/**
* @see org.eclipse.jface.text.source.ICharacterPairMatcher#dispose()
*/
@Override
public void dispose() {
clear();
fDocument = null;
}
/*
* @see org.eclipse.jface.text.source.ICharacterPairMatcher#clear()
*/
@Override
public void clear() {
}
private boolean matchPairsAt() {
int i;
int pairIndex1 = fPairs.length;
int pairIndex2 = fPairs.length;
fStartPos = -1;
fEndPos = -1;
// get the char preceding the start position
try {
char prevChar = fDocument.getChar(Math.max(fOffset - 1, 0));
// search for opening peer character next to the activation point
for (i = 0; i < fPairs.length; i = i + 2) {
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;
}
}
if (fEndPos > -1) {
fAnchor = RIGHT;
fStartPos = searchForOpeningPeer(fEndPos, fPairs[pairIndex2 - 1], fPairs[pairIndex2], fDocument);
if (fStartPos > -1)
return true;
fEndPos = -1;
} else if (fStartPos > -1) {
fAnchor = LEFT;
fEndPos = searchForClosingPeer(fStartPos, fPairs[pairIndex1], fPairs[pairIndex1 + 1], fDocument);
if (fEndPos > -1)
return true;
fStartPos = -1;
}
} catch (BadLocationException x) {
}
return false;
}
private int searchForClosingPeer(int offset, char openingPeer, char closingPeer, IDocument document)
throws BadLocationException {
boolean useGenericsHeuristic = openingPeer == '<';
if (useGenericsHeuristic && !fHighlightAngularBrackets) {
return -1;
}
PHPHeuristicScanner scanner = PHPHeuristicScanner.createHeuristicScanner(document, offset, false);
if (useGenericsHeuristic && !isTypeParameterBracket(offset, document, scanner)) {
return -1;
}
int closedAt = scanner.findClosingPeer(offset + 1, openingPeer, closingPeer);
if (closedAt != PHPHeuristicScanner.NOT_FOUND) {
// bug 493134 , detect mismatch, like call(function() {});
for (int i = 0; i < fPairs.length; i += 2) {
if (fPairs[i] == openingPeer) {
continue;
}
int depth = 0;
int pos = offset + 1;
char[] pair = new char[] { fPairs[i], fPairs[i + 1] };
do {
int tmp = scanner.scanForward(pos, closedAt, pair);
if (tmp == PHPHeuristicScanner.NOT_FOUND) {
break;
}
if (document.getChar(tmp) == pair[0]) {
depth++;
} else {
depth--;
}
pos = tmp + 1;
} while (pos < closedAt);
if (depth != 0) {
return PHPHeuristicScanner.NOT_FOUND;
}
}
}
return closedAt;
}
private int searchForOpeningPeer(int offset, char openingPeer, char closingPeer, IDocument document)
throws BadLocationException {
boolean useGenericsHeuristic = openingPeer == '<';
if (useGenericsHeuristic && !fHighlightAngularBrackets) {
return -1;
}
PHPHeuristicScanner scanner = PHPHeuristicScanner.createHeuristicScanner(document, offset, false);
int peer = scanner.findOpeningPeer(offset - 1, PHPHeuristicScanner.UNBOUND, openingPeer, closingPeer);
if (peer == PHPHeuristicScanner.NOT_FOUND) {
return -1;
}
if (useGenericsHeuristic && !isTypeParameterBracket(peer, document, scanner)) {
return -1;
}
// bug 493134 , detect mismatch, like call(function() {call(|)});
if (searchForClosingPeer(peer, openingPeer, closingPeer, document) != offset) {
return -1;
}
return peer;
}
/**
* Checks if the angular bracket at <code>offset</code> is a type parameter
* bracket.
*
* @param offset
* the offset of the opening bracket
* @param document
* the document
* @param scanner
* a java heuristic scanner on <code>document</code>
* @return <code>true</code> if the bracket is part of a type parameter,
* <code>false</code> otherwise
* @since 3.1
*/
private boolean isTypeParameterBracket(int offset, IDocument document, PHPHeuristicScanner scanner) {
/*
* type parameter come after braces (closing or opening), semicolons, or
* after a Type name (heuristic: starts with capital character, or after
* a modifier keyword in a method declaration (visibility, static,
* synchronized, final)
*/
try {
IRegion line = document.getLineInformationOfOffset(offset);
int prevToken = scanner.previousToken(offset - 1, line.getOffset());
int prevTokenOffset = scanner.getPosition() + 1;
String previous = prevToken == Symbols.TokenEOF ? null
: document.get(prevTokenOffset, offset - prevTokenOffset).trim();
if (prevToken == Symbols.TokenLBRACE || prevToken == Symbols.TokenRBRACE
|| prevToken == Symbols.TokenSEMICOLON || prevToken == Symbols.TokenSYNCHRONIZED
|| prevToken == Symbols.TokenSTATIC
|| (prevToken == Symbols.TokenIDENT && isTypeParameterIntroducer(previous))
|| prevToken == Symbols.TokenEOF) {
return true;
}
} catch (BadLocationException e) {
return false;
}
return false;
}
/**
* Returns <code>true</code> if <code>identifier</code> is an identifier
* that could come right before a type parameter list. It uses a heuristic:
* if the identifier starts with an upper case, it is assumed a type name.
* Also, if <code>identifier</code> is a method modifier, it is assumed that
* the angular bracket is part of the generic type parameter of a method.
*
* @param identifier
* the identifier to check
* @return <code>true</code> if the identifier could introduce a type
* parameter list
* @since 3.1
*/
private boolean isTypeParameterIntroducer(String identifier) {
return identifier.length() > 0 && (Character.isUpperCase(identifier.charAt(0)) || identifier.startsWith("final") //$NON-NLS-1$
|| identifier.startsWith("public") //$NON-NLS-1$
|| identifier.startsWith("protected") //$NON-NLS-1$
|| identifier.startsWith("private")); //$NON-NLS-1$
}
}