/*******************************************************************************
* Copyright (c) 2010, 2011 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
*******************************************************************************/
package org.eclipse.wst.sse.ui.internal.handlers;
import java.lang.reflect.InvocationTargetException;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.jface.dialogs.ProgressMonitorDialog;
import org.eclipse.jface.operation.IRunnableWithProgress;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.DocumentRewriteSession;
import org.eclipse.jface.text.DocumentRewriteSessionType;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IDocumentExtension4;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ITextSelection;
import org.eclipse.jface.text.ITypedRegion;
import org.eclipse.jface.text.Position;
import org.eclipse.swt.widgets.Display;
import org.eclipse.ui.texteditor.ITextEditor;
import org.eclipse.wst.sse.core.StructuredModelManager;
import org.eclipse.wst.sse.core.internal.provisional.IStructuredModel;
import org.eclipse.wst.sse.core.internal.provisional.text.IStructuredDocument;
import org.eclipse.wst.sse.ui.StructuredTextEditor;
import org.eclipse.wst.sse.ui.internal.Logger;
import org.eclipse.wst.sse.ui.internal.SSEUIMessages;
import org.eclipse.wst.sse.ui.internal.StructuredTextViewer;
import org.eclipse.wst.sse.ui.internal.comment.BlockCommentingStrategy;
import org.eclipse.wst.sse.ui.internal.comment.CommentingStrategy;
import org.eclipse.wst.sse.ui.internal.comment.CommentingStrategyRegistry;
import org.eclipse.wst.sse.ui.internal.comment.LineCommentingStrategy;
/**
* <p>A comment handler to toggle line comments, this means that if a
* comment already exists on a line then toggling it will remove the comment,
* if the line in question is not already commented then it will not be commented.
* If multiple lines are selected each will be commented separately. The handler
* first attempts to find a {@link LineCommentingStrategy} for a line, if it can
* not find one then it will try and find a {@link BlockCommentingStrategy} to
* wrap just that line in.</p>
*
* <p>If a great number of lines are being toggled then a progress dialog will be
* displayed because this can be a timely process</p>
*/
public final class ToggleLineCommentHandler extends AbstractCommentHandler {
/** if toggling more then this many lines then use a busy indicator */
private static final int TOGGLE_LINES_MAX_NO_BUSY_INDICATOR = 10;
/**
* @see org.eclipse.wst.sse.ui.internal.handlers.AbstractCommentHandler#processAction(
* org.eclipse.ui.texteditor.ITextEditor, org.eclipse.wst.sse.core.internal.provisional.text.IStructuredDocument,
* org.eclipse.jface.text.ITextSelection)
*/
protected void processAction(ITextEditor textEditor,
final IStructuredDocument document, ITextSelection textSelection) {
IStructuredModel model = null;
DocumentRewriteSession session = null;
boolean changed = false;
try {
// get text selection lines info
int selectionStartLine = textSelection.getStartLine();
int selectionEndLine = textSelection.getEndLine();
int selectionEndLineOffset = document.getLineOffset(selectionEndLine);
int selectionEndOffset = textSelection.getOffset() + textSelection.getLength();
// adjust selection end line
if ((selectionEndLine > selectionStartLine) && (selectionEndLineOffset == selectionEndOffset)) {
selectionEndLine--;
}
// save the selection position since it will be changing
Position selectionPosition = null;
selectionPosition = new Position(textSelection.getOffset(), textSelection.getLength());
document.addPosition(selectionPosition);
model = StructuredModelManager.getModelManager().getModelForEdit(document);
if (model != null) {
//makes it so one undo will undo all the edits to the document
model.beginRecording(this, SSEUIMessages.ToggleComment_label, SSEUIMessages.ToggleComment_description);
//keeps listeners from doing anything until updates are all done
model.aboutToChangeModel();
if(document instanceof IDocumentExtension4) {
session = ((IDocumentExtension4)document).startRewriteSession(DocumentRewriteSessionType.UNRESTRICTED);
}
changed = true;
//get the display for the editor if we can
Display display = null;
if(textEditor instanceof StructuredTextEditor) {
StructuredTextViewer viewer = ((StructuredTextEditor)textEditor).getTextViewer();
if(viewer != null) {
display = viewer.getControl().getDisplay();
}
}
//create the toggling operation
IRunnableWithProgress toggleCommentsRunnable = new ToggleLinesRunnable(
model.getContentTypeIdentifier(), document, selectionStartLine, selectionEndLine, display);
//if toggling lots of lines then use progress monitor else just run the operation
if((selectionEndLine - selectionStartLine) > TOGGLE_LINES_MAX_NO_BUSY_INDICATOR && display != null) {
ProgressMonitorDialog dialog = new ProgressMonitorDialog(display.getActiveShell());
dialog.run(false, true, toggleCommentsRunnable);
} else {
toggleCommentsRunnable.run(new NullProgressMonitor());
}
}
} catch (InvocationTargetException e) {
Logger.logException("Problem running toggle comment progess dialog.", e); //$NON-NLS-1$
} catch (InterruptedException e) {
Logger.logException("Problem running toggle comment progess dialog.", e); //$NON-NLS-1$
} catch (BadLocationException e) {
Logger.logException("The given selection " + textSelection + " must be invalid", e); //$NON-NLS-1$ //$NON-NLS-2$
} finally {
//clean everything up
if(session != null && document instanceof IDocumentExtension4) {
((IDocumentExtension4)document).stopRewriteSession(session);
}
if(model != null) {
model.endRecording(this);
if(changed) {
model.changedModel();
}
model.releaseFromEdit();
}
}
}
/**
* <p>The actual line toggling takes place in a runnable so it can be
* run as part of a progress dialog if there are many lines to toggle
* and thus the operation will take a noticeable amount of time the user
* should be aware of, this also allows for the operation to be canceled
* by the user</p>
*
*/
private static class ToggleLinesRunnable implements IRunnableWithProgress {
/** the content type for the document being commented */
private String fContentType;
/** the document that the lines will be toggled on */
private IStructuredDocument fDocument;
/** the first line in the document to toggle */
private int fSelectionStartLine;
/** the last line in the document to toggle */
private int fSelectionEndLine;
/** the display, so that it can be updated during a long operation */
private Display fDisplay;
/**
* @param model {@link IStructuredModel} that the lines will be toggled on
* @param document {@link IDocument} that the lines will be toggled on
* @param selectionStartLine first line in the document to toggle
* @param selectionEndLine last line in the document to toggle
* @param display {@link Display}, so that it can be updated during a long operation
*/
protected ToggleLinesRunnable(String contentTypeIdentifier, IStructuredDocument document,
int selectionStartLine, int selectionEndLine, Display display) {
this.fContentType = contentTypeIdentifier;
this.fDocument = document;
this.fSelectionStartLine = selectionStartLine;
this.fSelectionEndLine = selectionEndLine;
this.fDisplay = display;
}
/**
* @see org.eclipse.jface.operation.IRunnableWithProgress#run(org.eclipse.core.runtime.IProgressMonitor)
*/
public void run(IProgressMonitor monitor) {
//start work
monitor.beginTask(SSEUIMessages.ToggleComment_progress,
this.fSelectionEndLine-this.fSelectionStartLine);
try {
final CommentingStrategy[] strategies = new CommentingStrategy[fSelectionEndLine - fSelectionStartLine + 1];
final int[] regions = new int[fSelectionEndLine - fSelectionStartLine + 1];
boolean shouldComment = false;
int strategyCount = 0;
//toggle each line so long as task not canceled
for (int line = this.fSelectionStartLine;
line <= this.fSelectionEndLine && !monitor.isCanceled(); ++line) {
//allows the user to be able to click the cancel button
readAndDispatch(this.fDisplay);
//get the line region
IRegion lineRegion = this.fDocument.getLineInformation(line);
//don't toggle empty lines
String content = this.fDocument.get(lineRegion.getOffset(), lineRegion.getLength());
if (content.trim().length() > 0) {
//try to get a line comment type
ITypedRegion[] lineTypedRegions =
this.fDocument.computePartitioning(lineRegion.getOffset(), lineRegion.getLength());
CommentingStrategy commentType = CommentingStrategyRegistry.getDefault().getLineCommentingStrategy(
this.fContentType, lineTypedRegions);
//could not find line comment type so find block comment type to use on line
if(commentType == null) {
commentType = CommentingStrategyRegistry.getDefault().getBlockCommentingStrategy(
this.fContentType, lineTypedRegions);
}
//toggle the comment on the line
if(commentType != null) {
strategies[strategyCount] = commentType;
regions[strategyCount++] = line;
if (!shouldComment && !commentType.alreadyCommenting(this.fDocument, lineTypedRegions)) {
shouldComment = true;
}
}
}
monitor.worked(1);
}
for (int i = 0; i < strategyCount; i++) {
final IRegion lineRegion = fDocument.getLineInformation( regions[i] );
if (shouldComment) {
strategies[i].apply(this.fDocument, lineRegion.getOffset(), lineRegion.getLength());
}
else {
strategies[i].remove(this.fDocument, lineRegion.getOffset(), lineRegion.getLength(), true);
}
monitor.worked(1);
}
} catch(BadLocationException e) {
Logger.logException("Bad location while toggling comments.", e); //$NON-NLS-1$
}
//done work
monitor.done();
}
/**
* <p>When calling {@link Display#readAndDispatch()} the game is off as to whose code you maybe
* calling into because of event handling/listeners/etc. The only important thing is that
* the UI has been given a chance to react to user clicks. Thus the logging of most {@link Exception}s
* and {@link Error}s as caused by {@link Display#readAndDispatch()} because they are not caused
* by this code and do not effect it.</p>
*
* @param display the {@link Display} to call <code>readAndDispatch</code>
* on with exception/error handling.
*/
private void readAndDispatch(Display display) {
try {
display.readAndDispatch();
}
catch (Exception e) {
Logger.log(Logger.WARNING,
"Exception caused by readAndDispatch, not caused by or fatal to caller", e);
}
catch (LinkageError e) {
Logger.log(Logger.WARNING,
"LinkageError caused by readAndDispatch, not caused by or fatal to caller", e);
}
catch (VirtualMachineError e) {
// re-throw these
throw e;
}
catch (ThreadDeath e) {
// re-throw these
throw e;
}
catch (Error e) {
// catch every error, except for a few that we don't want to handle
Logger.log(Logger.WARNING,
"Error caused by readAndDispatch, not caused by or fatal to caller", e);
}
}
}
}