/*******************************************************************************
* Copyright (c) 2006, 2010 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.cdt.internal.ui.editor;
import java.util.HashMap;
import java.util.Map;
import java.util.ResourceBundle;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ITextOperationTarget;
import org.eclipse.jface.text.ITextSelection;
import org.eclipse.jface.text.ITypedRegion;
import org.eclipse.jface.text.Region;
import org.eclipse.jface.text.TextUtilities;
import org.eclipse.jface.text.TextViewer;
import org.eclipse.jface.text.source.ISourceViewer;
import org.eclipse.jface.text.source.SourceViewerConfiguration;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.swt.custom.BusyIndicator;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.texteditor.ITextEditor;
import org.eclipse.ui.texteditor.ResourceAction;
import org.eclipse.ui.texteditor.TextEditorAction;
import org.eclipse.cdt.ui.CUIPlugin;
/**
* An action which toggles comment prefixes on the selected lines.
*
* @since 4.0.0
*/
public final class ToggleCommentAction extends TextEditorAction {
/** The text operation target */
private ITextOperationTarget fOperationTarget;
/** The document partitioning */
private String fDocumentPartitioning;
/** The comment prefixes */
private Map<String, String[]> fPrefixesMap;
/**
* Creates and initializes the action for the given text editor. The action
* configures its visual representation from the given resource bundle.
*
* @param bundle the resource bundle
* @param prefix a prefix to be prepended to the various resource keys
* (described in <code>ResourceAction</code> constructor), or
* <code>null</code> if none
* @param editor the text editor
* @see ResourceAction#ResourceAction(ResourceBundle, String, int)
*/
public ToggleCommentAction(ResourceBundle bundle, String prefix, ITextEditor editor) {
super(bundle, prefix, editor);
}
/**
* Implementation of the <code>IAction</code> prototype. Checks if the selected
* lines are all commented or not and uncomments/comments them respectively.
*/
@Override
public void run() {
if (fOperationTarget == null || fDocumentPartitioning == null || fPrefixesMap == null)
return;
ITextEditor editor= getTextEditor();
if (editor == null)
return;
if (!validateEditorInputState())
return;
final int operationCode;
if (isSelectionCommented(editor.getSelectionProvider().getSelection()))
operationCode= ITextOperationTarget.STRIP_PREFIX;
else
operationCode= ITextOperationTarget.PREFIX;
Shell shell= editor.getSite().getShell();
if (!fOperationTarget.canDoOperation(operationCode)) {
if (shell != null) {
MessageDialog.openError(shell, CEditorMessages.ToggleComment_error_title,
CEditorMessages.ToggleComment_error_message);
}
return;
}
Display display= null;
if (shell != null && !shell.isDisposed())
display= shell.getDisplay();
BusyIndicator.showWhile(display, new Runnable() {
public void run() {
fOperationTarget.doOperation(operationCode);
}
});
}
/**
* Is the given selection single-line commented?
*
* @param selection Selection to check
* @return <code>true</code> iff all selected lines are commented
*/
private boolean isSelectionCommented(ISelection selection) {
if (!(selection instanceof ITextSelection))
return false;
ITextSelection textSelection= (ITextSelection) selection;
if (textSelection.getStartLine() < 0 || textSelection.getEndLine() < 0)
return false;
IDocument document= getTextEditor().getDocumentProvider().getDocument(getTextEditor().getEditorInput());
try {
IRegion block= getTextBlockFromSelection(textSelection, document);
ITypedRegion[] regions= TextUtilities.computePartitioning(document, fDocumentPartitioning,
block.getOffset(), block.getLength(), false);
int[] lines= new int[regions.length * 2]; // [startline, endline, startline, endline, ...]
// For each partition in the text selection, figure out the startline and endline.
// Count the number of lines that are selected.
for (int i = 0, j = 0; i < regions.length; i++, j+= 2) {
// Start line of region
lines[j]= getFirstCompleteLineOfRegion(regions[i], document);
// End line of region
int length= regions[i].getLength();
int offset= regions[i].getOffset() + length;
if (length > 0)
offset--;
// If there is no startline for this region (startline = -1),
// then there is no endline,
// otherwise, get the line number of the endline and store it in the array.
lines[j + 1]= (lines[j] == -1 ? -1 : document.getLineOfOffset(offset));
// We could count the number of lines that are selected in this region
// lineCount += lines[j + 1] - lines[j] + 1;
assert i < regions.length;
assert j < regions.length * 2;
}
// Perform the check
boolean hasComment= false;
for (int i = 0, j = 0; i < regions.length; i++, j += 2) {
String[] prefixes= fPrefixesMap.get(regions[i].getType());
if (prefixes != null && prefixes.length > 0 && lines[j] >= 0 && lines[j + 1] >= 0) {
if (isBlockCommented(lines[j], lines[j + 1], prefixes, document)) {
hasComment= true;
} else if (!isBlockEmpty(lines[j], lines[j + 1], document)) {
return false;
}
}
}
return hasComment;
} catch (BadLocationException e) {
CUIPlugin.log(e); // Should not happen
}
return false;
}
/**
* Creates a region describing the text block (something that starts at
* the beginning of a line) completely containing the current selection.
*
* Note, the implementation has to match {@link TextViewer}.getTextBlockFromSelection().
*
* @param selection The selection to use
* @param document The document
* @return the region describing the text block comprising the given selection
* @throws BadLocationException
*/
private IRegion getTextBlockFromSelection(ITextSelection selection, IDocument document) throws BadLocationException {
int start= document.getLineOffset(selection.getStartLine());
int end;
int endLine= selection.getEndLine();
if (document.getNumberOfLines() > endLine+1) {
end= document.getLineOffset(endLine+1);
} else {
end= document.getLength();
}
return new Region(start, end - start);
}
/**
* Returns the index of the first line whose start offset is in the given text range.
*
* @param region the text range in characters where to find the line
* @param document The document
* @return the first line whose start index is in the given range, -1 if there is no such line
*/
private int getFirstCompleteLineOfRegion(IRegion region, IDocument document) {
try {
int startLine= document.getLineOfOffset(region.getOffset());
int offset= document.getLineOffset(startLine);
if (offset >= region.getOffset())
return startLine;
offset= document.getLineOffset(startLine + 1);
return (offset > region.getOffset() + region.getLength() ? -1 : startLine + 1);
} catch (BadLocationException e) {
CUIPlugin.log(e); // Should not happen
}
return -1;
}
/**
* Determines whether each line is prefixed by one of the prefixes.
*
* @param startLine Start line in document
* @param endLine End line in document
* @param prefixes Possible comment prefixes
* @param document The document
* @return <code>true</code> iff each line from <code>startLine</code>
* to and including <code>endLine</code> is prepended by one
* of the <code>prefixes</code>, ignoring whitespace at the
* begin of line
*/
private boolean isBlockCommented(int startLine, int endLine, String[] prefixes, IDocument document) {
try {
// Check for occurrences of prefixes in the given lines
boolean hasComment = false;
for (int i= startLine; i <= endLine; i++) {
IRegion line= document.getLineInformation(i);
String text= document.get(line.getOffset(), line.getLength());
boolean isEmptyLine = text.trim().length() == 0;
if(isEmptyLine) {
continue;
}
int[] found= TextUtilities.indexOf(prefixes, text, 0);
if (found[0] == -1) {
// Found a line which is not commented
return false;
}
String s= document.get(line.getOffset(), found[0]);
s= s.trim();
if (s.length() != 0) {
// Found a line which is not commented
return false;
}
hasComment = true;
}
return hasComment;
} catch (BadLocationException e) {
CUIPlugin.log(e); // Should not happen
}
return false;
}
/**
* Determines whether each line is empty
*
* @param startLine Start line in document
* @param endLine End line in document
* @param document The document
* @return <code>true</code> if each line from <code>startLine</code>
* to and including <code>endLine</code> is empty
*/
private boolean isBlockEmpty(int startLine, int endLine, IDocument document) {
try {
for (int i= startLine; i <= endLine; i++) {
IRegion line= document.getLineInformation(i);
String text= document.get(line.getOffset(), line.getLength());
boolean isEmptyLine = text.trim().length() == 0;
if(!isEmptyLine) {
return false;
}
}
return true;
} catch (BadLocationException e) {
CUIPlugin.log(e); // Should not happen
}
return false;
}
/**
* Implementation of the <code>IUpdate</code> prototype method discovers
* the operation through the current editor's
* <code>ITextOperationTarget</code> adapter, and sets the enabled state
* accordingly.
*/
@Override
public void update() {
super.update();
if (!canModifyEditor()) {
setEnabled(false);
return;
}
ITextEditor editor= getTextEditor();
if (fOperationTarget == null && editor != null)
fOperationTarget= (ITextOperationTarget) editor.getAdapter(ITextOperationTarget.class);
boolean isEnabled= (fOperationTarget != null && fOperationTarget.canDoOperation(ITextOperationTarget.PREFIX) &&
fOperationTarget.canDoOperation(ITextOperationTarget.STRIP_PREFIX));
setEnabled(isEnabled);
}
/*
* @see TextEditorAction#setEditor(ITextEditor)
*/
@Override
public void setEditor(ITextEditor editor) {
super.setEditor(editor);
fOperationTarget= null;
}
/**
* For the different content types, get its default comment prefix and store the prefixes.
* @param sourceViewer
* @param configuration
*/
public void configure(ISourceViewer sourceViewer, SourceViewerConfiguration configuration) {
fPrefixesMap= null;
String[] types= configuration.getConfiguredContentTypes(sourceViewer);
Map<String, String[]> prefixesMap= new HashMap<String, String[]>(types.length);
for (String type : types) {
String[] prefixes= configuration.getDefaultPrefixes(sourceViewer, type);
if (prefixes != null && prefixes.length > 0) {
int emptyPrefixes= 0;
for (String prefixe : prefixes) {
if (prefixe.length() == 0)
emptyPrefixes++;
}
if (emptyPrefixes > 0) {
String[] nonemptyPrefixes= new String[prefixes.length - emptyPrefixes];
for (int j= 0, k= 0; j < prefixes.length; j++) {
String prefix= prefixes[j];
if (prefix.length() != 0) {
nonemptyPrefixes[k]= prefix;
k++;
}
}
prefixes= nonemptyPrefixes;
}
prefixesMap.put(type, prefixes);
}
}
fDocumentPartitioning= configuration.getConfiguredDocumentPartitioning(sourceViewer);
fPrefixesMap= prefixesMap;
}
}