/*******************************************************************************
* Copyright (c) 2000, 2012 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
* Sergey Prigogin (Google)
*******************************************************************************/
package org.eclipse.cdt.internal.ui.text.correction;
import java.util.ConcurrentModificationException;
import java.util.Iterator;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.ITextSelection;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.Position;
import org.eclipse.jface.text.source.Annotation;
import org.eclipse.jface.text.source.IAnnotationAccessExtension;
import org.eclipse.jface.text.source.IAnnotationModel;
import org.eclipse.jface.text.source.IAnnotationPresentation;
import org.eclipse.jface.text.source.ImageUtilities;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.editors.text.EditorsUI;
import org.eclipse.ui.texteditor.AnnotationPreference;
import org.eclipse.ui.texteditor.ITextEditor;
import org.eclipse.cdt.core.dom.ast.IASTTranslationUnit;
import org.eclipse.cdt.core.model.ICElement;
import org.eclipse.cdt.core.model.ILanguage;
import org.eclipse.cdt.core.model.ITranslationUnit;
import org.eclipse.cdt.core.model.IWorkingCopy;
import org.eclipse.cdt.ui.CDTSharedImages;
import org.eclipse.cdt.ui.CUIPlugin;
import org.eclipse.cdt.ui.PreferenceConstants;
import org.eclipse.cdt.internal.core.model.ASTCache.ASTRunnable;
import org.eclipse.cdt.internal.ui.editor.ASTProvider;
import org.eclipse.cdt.internal.ui.util.EditorUtility;
import org.eclipse.cdt.internal.ui.viewsupport.ISelectionListenerWithAST;
import org.eclipse.cdt.internal.ui.viewsupport.SelectionListenerWithASTManager;
/**
*
*/
public class QuickAssistLightBulbUpdater {
public static class AssistAnnotation extends Annotation implements IAnnotationPresentation {
//XXX: To be fully correct this should be a non-static field in QuickAssistLightBulbUpdater
private static final int LAYER;
static {
Annotation annotation= new Annotation("org.eclipse.jdt.ui.warning", false, null); //$NON-NLS-1$
AnnotationPreference preference= EditorsUI.getAnnotationPreferenceLookup().getAnnotationPreference(annotation);
if (preference != null)
LAYER= preference.getPresentationLayer() - 1;
else
LAYER= IAnnotationAccessExtension.DEFAULT_LAYER;
}
private Image fImage;
public AssistAnnotation() {
}
/*
* @see org.eclipse.jface.text.source.IAnnotationPresentation#getLayer()
*/
@Override
public int getLayer() {
return LAYER;
}
private Image getImage() {
if (fImage == null) {
fImage= CDTSharedImages.getImage(CDTSharedImages.IMG_OBJS_QUICK_ASSIST);
}
return fImage;
}
/* (non-Javadoc)
* @see org.eclipse.jface.text.source.Annotation#paint(org.eclipse.swt.graphics.GC, org.eclipse.swt.widgets.Canvas, org.eclipse.swt.graphics.Rectangle)
*/
@Override
public void paint(GC gc, Canvas canvas, Rectangle r) {
ImageUtilities.drawImage(getImage(), gc, canvas, r, SWT.CENTER, SWT.TOP);
}
}
private final Annotation fAnnotation;
private boolean fIsAnnotationShown;
private ITextEditor fEditor;
private ITextViewer fViewer;
private ISelectionListenerWithAST fListener;
private IPropertyChangeListener fPropertyChangeListener;
public QuickAssistLightBulbUpdater(ITextEditor part, ITextViewer viewer) {
fEditor= part;
fViewer= viewer;
fAnnotation= new AssistAnnotation();
fIsAnnotationShown= false;
fPropertyChangeListener= null;
}
public boolean isSetInPreferences() {
return PreferenceConstants.getPreferenceStore().getBoolean(PreferenceConstants.EDITOR_QUICKASSIST_LIGHTBULB);
}
private void installSelectionListener() {
fListener= new ISelectionListenerWithAST() {
@Override
public void selectionChanged(IEditorPart part,
ITextSelection selection, IASTTranslationUnit astRoot) {
doSelectionChanged(selection.getOffset(), selection.getLength(), astRoot);
}
};
SelectionListenerWithASTManager.getDefault().addListener(fEditor, fListener);
}
private void uninstallSelectionListener() {
if (fListener != null) {
SelectionListenerWithASTManager.getDefault().removeListener(fEditor, fListener);
fListener= null;
}
IAnnotationModel model= getAnnotationModel();
if (model != null) {
removeLightBulb(model);
}
}
public void install() {
if (isSetInPreferences()) {
installSelectionListener();
}
if (fPropertyChangeListener == null) {
fPropertyChangeListener= new IPropertyChangeListener() {
@Override
public void propertyChange(PropertyChangeEvent event) {
doPropertyChanged(event.getProperty());
}
};
PreferenceConstants.getPreferenceStore().addPropertyChangeListener(fPropertyChangeListener);
}
}
public void uninstall() {
uninstallSelectionListener();
if (fPropertyChangeListener != null) {
PreferenceConstants.getPreferenceStore().removePropertyChangeListener(fPropertyChangeListener);
fPropertyChangeListener= null;
}
}
protected void doPropertyChanged(String property) {
if (property.equals(PreferenceConstants.EDITOR_QUICKASSIST_LIGHTBULB)) {
if (isSetInPreferences()) {
IWorkingCopy workingCopy = CUIPlugin.getDefault().getWorkingCopyManager().getWorkingCopy(fEditor.getEditorInput());
if (workingCopy != null) {
installSelectionListener();
final Point point= fViewer.getSelectedRange();
ASTProvider.getASTProvider().runOnAST(workingCopy, ASTProvider.WAIT_IF_OPEN, null, new ASTRunnable() {
@Override
public IStatus runOnAST(ILanguage lang, IASTTranslationUnit astRoot) {
if (astRoot != null) {
doSelectionChanged(point.x, point.y, astRoot);
}
return Status.OK_STATUS;
}
});
}
} else {
uninstallSelectionListener();
}
}
}
private ITranslationUnit getTranslationUnit() {
ICElement elem= EditorUtility.getEditorInputCElement(fEditor);
if (elem instanceof ITranslationUnit) {
return (ITranslationUnit) elem;
}
return null;
}
private IAnnotationModel getAnnotationModel() {
return CUIPlugin.getDefault().getDocumentProvider().getAnnotationModel(fEditor.getEditorInput());
}
private IDocument getDocument() {
return CUIPlugin.getDefault().getDocumentProvider().getDocument(fEditor.getEditorInput());
}
private void doSelectionChanged(int offset, int length, IASTTranslationUnit astRoot) {
final IAnnotationModel model= getAnnotationModel();
final ITranslationUnit tu= getTranslationUnit();
if (model == null || tu == null) {
return;
}
final CorrectionContext context= new CorrectionContext(tu, offset, length);
boolean hasQuickFix= hasQuickFixLightBulb(model, context.getSelectionOffset());
if (hasQuickFix) {
removeLightBulb(model);
return; // there is already a quick fix light bulb at the new location
}
calculateLightBulb(model, context);
}
/*
* Needs to be called synchronized
*/
private void calculateLightBulb(IAnnotationModel model, CorrectionContext context) {
boolean needsAnnotation= CCorrectionProcessor.hasAssists(context);
if (fIsAnnotationShown) {
model.removeAnnotation(fAnnotation);
}
if (needsAnnotation) {
model.addAnnotation(fAnnotation, new Position(context.getSelectionOffset(), context.getSelectionLength()));
}
fIsAnnotationShown= needsAnnotation;
}
private void removeLightBulb(IAnnotationModel model) {
synchronized (this) {
if (fIsAnnotationShown) {
model.removeAnnotation(fAnnotation);
fIsAnnotationShown= false;
}
}
}
/*
* Tests if there is already a quick fix light bulb on the current line
*/
private boolean hasQuickFixLightBulb(IAnnotationModel model, int offset) {
try {
IDocument document= getDocument();
if (document == null) {
return false;
}
// we access a document and annotation model from within a job
// since these are only read accesses, we won't hurt anyone else if
// this goes boink
// may throw an IndexOutOfBoundsException upon concurrent document modification
int currLine= document.getLineOfOffset(offset);
// this iterator is not protected, it may throw ConcurrentModificationExceptions
Iterator<?> iter= model.getAnnotationIterator();
while (iter.hasNext()) {
Annotation annot= (Annotation) iter.next();
if (CCorrectionProcessor.isQuickFixableType(annot)) {
// may throw an IndexOutOfBoundsException upon concurrent annotation model changes
Position pos= model.getPosition(annot);
if (pos != null) {
// may throw an IndexOutOfBoundsException upon concurrent document modification
int startLine= document.getLineOfOffset(pos.getOffset());
if (startLine == currLine && CCorrectionProcessor.hasCorrections(annot)) {
return true;
}
}
}
}
} catch (BadLocationException e) {
// ignore
} catch (IndexOutOfBoundsException e) {
// concurrent modification - too bad, ignore
} catch (ConcurrentModificationException e) {
// concurrent modification - too bad, ignore
}
return false;
}
}