/*
* Copyright (c) 2003-2004 Christopher Lenz and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Common Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/cpl-v10.html
*
* Contributors:
* Christopher Lenz - initial API and implementation
*
* $Id: CssDoubleClickStrategy.java,v 1.1 2004-09-02 18:11:48 jsurfer Exp $
*/
package net.sourceforge.phpeclipse.css.ui.internal.text;
import net.sourceforge.phpeclipse.css.core.internal.text.CssTextUtils;
import net.sourceforge.phpeclipse.css.ui.CssUI;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ITextDoubleClickStrategy;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.Region;
import org.eclipse.jface.text.source.ICharacterPairMatcher;
import org.eclipse.jface.util.Assert;
/**
* Strategy for selecting CSS identifiers on double click in the editor.
*
* This strategy implements selection of CSS identifiers on double click inside
* an identifier, as well as selection of blocks delimited by square brackets,
* curly braces and parenthesis when the user double clicks directly after
* either the opening or the closing delimiter.
*/
public class CssDoubleClickStrategy implements ITextDoubleClickStrategy {
// Instance Variables ------------------------------------------------------
/**
* The pair matcher used to select ranges delimited by matching pairs of
* braces, brackets and parenthesis.
*/
private ICharacterPairMatcher pairMatcher = new CssPairMatcher();
// ITextDoubleClickStrategy Implementation ---------------------------------
/*
* @see ITextDoubleClickStrategy#doubleClicked(ITextViewer)
*/
public void doubleClicked(ITextViewer viewer) {
IDocument document = viewer.getDocument();
if (document.getLength() == 0) {
return;
}
int offset = viewer.getSelectedRange().x;
Assert.isLegal(offset >= 0,
"Double click offset may not be negative"); //$NON-NLS-1$
Assert.isLegal(offset <= document.getLength(),
"Double click offset out of range"); //$NON-NLS-1$
IRegion region = pairMatcher.match(document, offset);
if ((region != null) && (region.getLength() >= 2)) {
viewer.setSelectedRange(region.getOffset() + 1,
region.getLength() - 2);
} else {
try {
region = getSurroundingIdentifier(document, offset);
if (region != null) {
viewer.setSelectedRange(
region.getOffset(), region.getLength());
}
} catch (BadLocationException e) {
CssUI.log("Failed to get surrounding " + //$NON-NLS-1$
"word for double click selection"); //$NON-NLS-1$
}
}
}
// Private Methods ---------------------------------------------------------
/**
* Returns the region that delimits the identifier surrounding the given
* offset into the document. If no identifier is found at the specified
* offset, this method returns null
.
*
* @param doc the document
* @param offset the zero-based offset into the document
* @return the region covered by the identifier, or null
if no
* identifier was found at that offset
*/
private IRegion getSurroundingIdentifier(IDocument doc, int offset)
throws BadLocationException {
IRegion retVal = null;
int length = doc.getLength();
offset = Math.min(offset, length - 1);
if (CssTextUtils.isCssIdentifierPart(doc.getChar(offset))) {
int start = offset;
while (start > 0) {
if (!CssTextUtils.isCssIdentifierPart(doc.getChar(start - 1))) {
break;
}
start--;
}
int end = offset;
while (end < (length - 1)) {
if (!CssTextUtils.isCssIdentifierPart(doc.getChar(end + 1))) {
break;
}
end++;
}
retVal = new Region(start, end - start + 1);
}
return retVal;
}
}