/*=============================================================================#
# Copyright (c) 2014-2016 Stephan Wahlbrink (WalWare.de) 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:
# Stephan Wahlbrink - initial API and implementation
#=============================================================================*/
package de.walware.ecommons.ltk.ui.sourceediting.actions;
import java.util.IdentityHashMap;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.text.AbstractDocument;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.BadPartitioningException;
import org.eclipse.jface.text.DocumentRewriteSession;
import org.eclipse.jface.text.DocumentRewriteSessionType;
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.TextUtilities;
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.text.edits.DeleteEdit;
import org.eclipse.text.edits.InsertEdit;
import org.eclipse.text.edits.MultiTextEdit;
import org.eclipse.text.edits.TextEdit;
import org.eclipse.ui.statushandlers.StatusManager;
import org.eclipse.ui.texteditor.IEditorStatusLine;
import de.walware.ecommons.ui.SharedUIResources;
import de.walware.ecommons.ltk.internal.ui.EditingMessages;
import de.walware.ecommons.ltk.ui.EditorUtil;
import de.walware.ecommons.ltk.ui.sourceediting.SourceEditor1;
import de.walware.ecommons.ltk.ui.sourceediting.SourceEditorViewer;
public class ToggleCommentHandler extends AbstractHandler {
private static final ConcurrentHashMap<String, Pattern> DEFAULT_PREFIX_MAP= new ConcurrentHashMap<>();
protected static Pattern getDefaultPrefixPattern(final String prefix) {
Pattern pattern= DEFAULT_PREFIX_MAP.get(prefix);
if (pattern == null) {
pattern= Pattern.compile("^[ \\t]*(" + Pattern.quote(prefix) + ")"); //$NON-NLS-1$ //$NON-NLS-2$
DEFAULT_PREFIX_MAP.putIfAbsent(prefix, pattern);
}
return pattern;
}
protected static final Pattern HTML_SPACE_PREFIX_PATTERN= Pattern.compile("^[ \\t]*(" + Pattern.quote("<!--") + " ?)"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
protected static final Pattern HTML_SPACE_POSTFIX_PATTERN= Pattern.compile("( ?" + Pattern.quote("-->") + "[ \\t]*)$"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
private final SourceEditor1 editor;
/** The text operation target */
private ITextOperationTarget operationTarget;
private final Map<String, String[]> contentTypePrefixes= new IdentityHashMap<>();
public ToggleCommentHandler(final SourceEditor1 editor) {
this.editor= editor;
setBaseEnabled(false);
}
protected SourceEditor1 getEditor() {
return this.editor;
}
@Override
public void setEnabled(final Object evaluationContext) {
if (this.editor.getViewer() instanceof SourceEditorViewer
&& !this.editor.isEditorInputModifiable()) {
setBaseEnabled(false);
return;
}
if (this.operationTarget == null) {
this.operationTarget= (ITextOperationTarget) this.editor.getAdapter(ITextOperationTarget.class);
}
setBaseEnabled(this.operationTarget != null
&& this.operationTarget.canDoOperation(ITextOperationTarget.PREFIX)
&& this.operationTarget.canDoOperation(ITextOperationTarget.STRIP_PREFIX) );
}
private ITextSelection getSelection() {
final ISelection selection= this.editor.getSelectionProvider().getSelection();
return (selection instanceof ITextSelection) ? (ITextSelection) selection : null;
}
@Override
public Object execute(final ExecutionEvent event) throws ExecutionException {
if (!this.editor.validateEditorInputState() || !isEnabled()) {
return null;
}
final ITextSelection selection= getSelection();
final AbstractDocument document= (AbstractDocument) this.editor.getViewer().getDocument();
final int operationCode= (isSelectionCommented(document, selection)) ?
ITextOperationTarget.STRIP_PREFIX : ITextOperationTarget.PREFIX;
final Shell shell= this.editor.getSite().getShell();
if (!this.operationTarget.canDoOperation(operationCode)) {
signalError();
return null;
}
Display display= null;
if (shell != null && !shell.isDisposed()) {
display= shell.getDisplay();
}
BusyIndicator.showWhile(display, new Runnable() {
@Override
public void run() {
ToggleCommentHandler.this.run(document, selection, operationCode);
}
});
return null;
}
protected void run(final AbstractDocument document, final ITextSelection selection,
final int operationCode) {
doRunOperation(operationCode);
}
protected void doRunOperation(final int operationCode) {
this.operationTarget.doOperation(operationCode);
}
protected String[] getPrefixes(final String contentType) {
String[] prefixes= this.contentTypePrefixes.get(contentType);
if (prefixes == null) {
prefixes= ((SourceEditorViewer) this.editor.getViewer()).getDefaultPrefixes(contentType);
if (prefixes == null) {
prefixes= new String[0];
}
else {
int numEmpty= 0;
for (int i= 0; i < prefixes.length; i++) {
if (prefixes[i].isEmpty()) {
numEmpty++;
}
}
if (numEmpty > 0) {
final String[] nonemptyPrefixes= new String[prefixes.length - numEmpty];
for (int i= 0, j= 0; i < prefixes.length; i++) {
final String prefix= prefixes[i];
if (!prefix.isEmpty()) {
nonemptyPrefixes[j++]= prefix;
}
}
prefixes= nonemptyPrefixes;
}
}
this.contentTypePrefixes.put(contentType, prefixes);
}
return prefixes;
}
protected Pattern getPrefixPattern(final String contentType, final String prefix) {
return getDefaultPrefixPattern(prefix);
}
protected Pattern getPostfixPattern(final String contentType, final String prefix) {
return null;
}
/**
* Is the given selection single-line commented?
*
* @param selection Selection to check
* @return <code>true</code> iff all selected lines are commented
* @throws BadPartitioningException
*/
private boolean isSelectionCommented(final AbstractDocument document, final ITextSelection selection) {
if (selection.getStartLine() < 0 || selection.getEndLine() < 0) {
return false;
}
try {
final IRegion block= EditorUtil.getTextBlockFromSelection(document,
selection.getOffset(), selection.getLength() );
final ITypedRegion[] regions= document.computePartitioning(
this.editor.getDocumentContentInfo().getPartitioning(),
block.getOffset(), block.getLength(), false );
final int[] lines= new int[regions.length * 2]; // [startline, endline, startline, endline, ...]
for (int i= 0, j= 0; i < regions.length; i++, j+= 2) {
// start line of region
lines[j]= getFirstCompleteLineOfRegion(document, regions[i]);
// end line of region
final int length= regions[i].getLength();
int offset= regions[i].getOffset() + length;
if (length > 0) {
offset--;
}
lines[j + 1]= (lines[j] == -1) ? -1 : document.getLineOfOffset(offset);
}
// Perform the check
for (int i= 0, j= 0; i < regions.length; i++, j+= 2) {
final String[] prefixes= getPrefixes(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)) {
return false;
}
}
}
return true;
}
catch (final BadLocationException | BadPartitioningException e) {
log(e);
}
return false;
}
/**
* 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(final int startLine, final int endLine, final String[] prefixes,
final IDocument document) {
try {
// check for occurrences of prefixes in the given lines
for (int i= startLine; i <= endLine; i++) {
final IRegion lineInfo= document.getLineInformation(i);
final String text= document.get(lineInfo.getOffset(), lineInfo.getLength());
final int[] found= TextUtilities.indexOf(prefixes, text, 0);
if (found[0] == -1) {
// found a line which is not commented
return false;
}
final String beforePrefix= text.substring(0, found[0]);
if (beforePrefix.trim().length() != 0) {
// found a line which is not commented
return false;
}
}
return true;
}
catch (final BadLocationException e) {
log(e);
}
return false;
}
/**
* Returns the index of the first line whose start offset is in the given text range.
*
* @param document The document
* @param region the text range in characters where to find the line
* @return the first line whose start index is in the given range, -1 if there is no such line
* @throws BadLocationException
*/
protected int getFirstCompleteLineOfRegion(final IDocument document, final IRegion region) throws BadLocationException {
final 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);
}
protected void doPrefix(final AbstractDocument document, final IRegion region,
final String prefix)
throws BadLocationException, BadPartitioningException {
final int startLine= document.getLineOfOffset(region.getOffset());
final int stopLine= (region.getLength() > 0) ?
document.getLineOfOffset(region.getOffset()+region.getLength()-1) :
startLine;
final MultiTextEdit multi= new MultiTextEdit(region.getOffset(), region.getLength());
for (int line= startLine; line <= stopLine; line++) {
multi.addChild(new InsertEdit(document.getLineOffset(line), prefix));
}
{ final DocumentRewriteSession rewriteSession= document.startRewriteSession(
DocumentRewriteSessionType.STRICTLY_SEQUENTIAL );
try {
multi.apply(document, TextEdit.NONE);
}
finally {
document.stopRewriteSession(rewriteSession);
}
}
}
protected void doPrefix(final AbstractDocument document, final IRegion region,
final String prefix, final String postfix)
throws BadLocationException, BadPartitioningException {
final int startLine= document.getLineOfOffset(region.getOffset());
final int stopLine= (region.getLength() > 0) ?
document.getLineOfOffset(region.getOffset()+region.getLength()-1) :
startLine;
final MultiTextEdit multi= new MultiTextEdit(region.getOffset(), region.getLength());
for (int line= startLine; line <= stopLine; line++) {
final IRegion lineInfo= document.getLineInformation(line);
multi.addChild(new InsertEdit(lineInfo.getOffset(), prefix));
multi.addChild(new InsertEdit(lineInfo.getOffset() + lineInfo.getLength(), postfix));
}
{ final DocumentRewriteSession rewriteSession= document.startRewriteSession(
DocumentRewriteSessionType.STRICTLY_SEQUENTIAL );
try {
multi.apply(document, TextEdit.NONE);
}
finally {
document.stopRewriteSession(rewriteSession);
}
}
}
protected void doStripPrefix(final AbstractDocument document, final IRegion region)
throws BadLocationException, BadPartitioningException {
final int startLine= document.getLineOfOffset(region.getOffset());
final int stopLine= (region.getLength() > 0) ?
document.getLineOfOffset(region.getOffset()+region.getLength()-1) :
startLine;
final MultiTextEdit multi= new MultiTextEdit(region.getOffset(), region.getLength());
for (int line= startLine; line <= stopLine; line++) {
final IRegion lineInfo= document.getLineInformation(line);
final String contentType= document.getContentType(
this.editor.getDocumentContentInfo().getPartitioning(),
lineInfo.getOffset(), false );
final String[] prefixes= getPrefixes(contentType);
final String text= document.get(lineInfo.getOffset(), lineInfo.getLength());
final int[] found= TextUtilities.indexOf(prefixes, text, 0);
assert (found[0] >= 0);
{ final Pattern pattern= getPrefixPattern(contentType, prefixes[found[1]]);
if (pattern != null) {
final Matcher matcher= pattern.matcher(text);
matcher.reset(text);
if (matcher.find()) {
multi.addChild(new DeleteEdit(
lineInfo.getOffset() + matcher.start(1),
matcher.end(1) - matcher.start(1) ));
}
}
else {
multi.addChild(new DeleteEdit(
lineInfo.getOffset() + found[0],
prefixes[found[1]].length() ));
}
}
{ final Pattern pattern= getPostfixPattern(contentType, prefixes[found[1]]);
if (pattern != null) {
final Matcher matcher= pattern.matcher(text);
if (matcher.find()) {
multi.addChild(new DeleteEdit(
lineInfo.getOffset() + matcher.start(1),
matcher.end(1) - matcher.start(1) ));
}
}
}
}
{ final DocumentRewriteSession rewriteSession= document.startRewriteSession(
DocumentRewriteSessionType.STRICTLY_SEQUENTIAL );
try {
multi.apply(document, TextEdit.NONE);
}
finally {
document.stopRewriteSession(rewriteSession);
}
}
}
protected void signalError() {
final IEditorStatusLine statusLine= (IEditorStatusLine) this.editor.getAdapter(IEditorStatusLine.class);
statusLine.setMessage(true, EditingMessages.ToggleCommentAction_error, null);
this.editor.getViewer().getTextWidget().getDisplay().beep();
}
protected void log(final Exception e) {
StatusManager.getManager().handle(new Status(IStatus.ERROR, SharedUIResources.PLUGIN_ID, 0,
"An error ocurred when executing toggle comment operation.", e ), StatusManager.LOG);
}
}