/*******************************************************************************
* Copyright (c) 2014, 2015 Cisco Systems, Inc. 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
*
*******************************************************************************/
package com.cisco.yangide.editor.editors;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.BadPositionCategoryException;
import org.eclipse.jface.text.DocumentEvent;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IDocumentListener;
import org.eclipse.jface.text.IPositionUpdater;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ISynchronizable;
import org.eclipse.jface.text.ITextInputListener;
import org.eclipse.jface.text.ITextPresentationListener;
import org.eclipse.jface.text.Position;
import org.eclipse.jface.text.Region;
import org.eclipse.jface.text.TextPresentation;
import org.eclipse.jface.text.source.SourceViewer;
import org.eclipse.swt.custom.StyleRange;
import com.cisco.yangide.editor.YangEditorPlugin;
import com.cisco.yangide.editor.editors.SemanticHighlightingManager.HighlightedPosition;
import com.cisco.yangide.editor.editors.SemanticHighlightingManager.Highlighting;
/**
* Semantic highlighting presenter - UI thread implementation.
*
* @author Alexey Kholupko
*/
public class SemanticHighlightingPresenter implements ITextPresentationListener, ITextInputListener, IDocumentListener {
/**
* Semantic highlighting position updater.
*/
private class HighlightingPositionUpdater implements IPositionUpdater {
/** The position category. */
private final String fCategory;
/**
* Creates a new updater for the given <code>category</code>.
*
* @param category the new category.
*/
public HighlightingPositionUpdater(String category) {
fCategory = category;
}
/*
* @see org.eclipse.jface.text.IPositionUpdater#update(org.eclipse.jface.text.DocumentEvent)
*/
@Override
public void update(DocumentEvent event) {
int eventOffset = event.getOffset();
int eventOldLength = event.getLength();
int eventEnd = eventOffset + eventOldLength;
try {
Position[] positions = event.getDocument().getPositions(fCategory);
for (int i = 0; i != positions.length; i++) {
HighlightedPosition position = (HighlightedPosition) positions[i];
// Also update deleted positions because they get deleted by the background
// thread and removed/invalidated only in the UI runnable
// if (position.isDeleted())
// continue;
int offset = position.getOffset();
int length = position.getLength();
int end = offset + length;
if (offset > eventEnd) {
updateWithPrecedingEvent(position, event);
} else if (end < eventOffset) {
updateWithSucceedingEvent(position, event);
} else if (offset <= eventOffset && end >= eventEnd) {
updateWithIncludedEvent(position, event);
} else if (offset <= eventOffset) {
updateWithOverEndEvent(position, event);
} else if (end >= eventEnd) {
updateWithOverStartEvent(position, event);
} else {
updateWithIncludingEvent(position, event);
}
}
} catch (BadPositionCategoryException e) {
// ignore and return
}
}
/**
* Update the given position with the given event. The event precedes the position.
*
* @param position The position
* @param event The event
*/
private void updateWithPrecedingEvent(HighlightedPosition position, DocumentEvent event) {
String newText = event.getText();
int eventNewLength = newText != null ? newText.length() : 0;
int deltaLength = eventNewLength - event.getLength();
position.setOffset(position.getOffset() + deltaLength);
}
/**
* Update the given position with the given event. The event succeeds the position.
*
* @param position The position
* @param event The event
*/
private void updateWithSucceedingEvent(HighlightedPosition position, DocumentEvent event) {
}
/**
* Update the given position with the given event. The event is included by the position.
*
* @param position The position
* @param event The event
*/
private void updateWithIncludedEvent(HighlightedPosition position, DocumentEvent event) {
int eventOffset = event.getOffset();
String newText = event.getText();
if (newText == null) {
newText = ""; //$NON-NLS-1$
}
int eventNewLength = newText.length();
int deltaLength = eventNewLength - event.getLength();
int offset = position.getOffset();
int length = position.getLength();
int end = offset + length;
int includedLength = 0;
while (includedLength < eventNewLength && Character.isJavaIdentifierPart(newText.charAt(includedLength))) {
includedLength++;
}
if (includedLength == eventNewLength) {
position.setLength(length + deltaLength);
} else {
int newLeftLength = eventOffset - offset + includedLength;
int excludedLength = eventNewLength;
while (excludedLength > 0 && Character.isJavaIdentifierPart(newText.charAt(excludedLength - 1))) {
excludedLength--;
}
int newRightOffset = eventOffset + excludedLength;
int newRightLength = end + deltaLength - newRightOffset;
if (newRightLength == 0) {
position.setLength(newLeftLength);
} else {
if (newLeftLength == 0) {
position.update(newRightOffset, newRightLength);
} else {
position.setLength(newLeftLength);
addPositionFromUI(newRightOffset, newRightLength, position.getHighlighting());
}
}
}
}
/**
* Update the given position with the given event. The event overlaps with the end of the
* position.
*
* @param position The position
* @param event The event
*/
private void updateWithOverEndEvent(HighlightedPosition position, DocumentEvent event) {
String newText = event.getText();
if (newText == null) {
newText = ""; //$NON-NLS-1$
}
int eventNewLength = newText.length();
int includedLength = 0;
while (includedLength < eventNewLength && Character.isJavaIdentifierPart(newText.charAt(includedLength))) {
includedLength++;
}
position.setLength(event.getOffset() - position.getOffset() + includedLength);
}
/**
* Update the given position with the given event. The event overlaps with the start of the
* position.
*
* @param position The position
* @param event The event
*/
private void updateWithOverStartEvent(HighlightedPosition position, DocumentEvent event) {
int eventOffset = event.getOffset();
int eventEnd = eventOffset + event.getLength();
String newText = event.getText();
if (newText == null) {
newText = ""; //$NON-NLS-1$
}
int eventNewLength = newText.length();
int excludedLength = eventNewLength;
while (excludedLength > 0 && Character.isJavaIdentifierPart(newText.charAt(excludedLength - 1))) {
excludedLength--;
}
int deleted = eventEnd - position.getOffset();
int inserted = eventNewLength - excludedLength;
position.update(eventOffset + excludedLength, position.getLength() - deleted + inserted);
}
/**
* Update the given position with the given event. The event includes the position.
*
* @param position The position
* @param event The event
*/
private void updateWithIncludingEvent(HighlightedPosition position, DocumentEvent event) {
position.delete();
position.update(event.getOffset(), 0);
}
}
/** Position updater */
private IPositionUpdater fPositionUpdater = new HighlightingPositionUpdater(getPositionCategory());
/** The source viewer this semantic highlighting reconciler is installed on */
private SourceViewer fSourceViewer;
/** The background presentation reconciler */
private YangPresentationReconciler fPresentationReconciler;
/** UI's current highlighted positions - can contain <code>null</code> elements */
private List<Position> fPositions = new ArrayList<Position>();
/** UI position lock */
private Object fPositionLock = new Object();
/** <code>true</code> iff the current reconcile is canceled. */
private boolean fIsCanceled = false;
/**
* Creates and returns a new highlighted position with the given offset, length and
* highlighting.
*/
public HighlightedPosition createHighlightedPosition(int offset, int length, Highlighting highlighting) {
// TODO: reuse deleted positions
return new HighlightedPosition(offset, length, highlighting, fPositionUpdater);
}
/**
* Adds all current positions to the given list.
*
* @param list The list
*/
public void addAllPositions(List<Position> list) {
synchronized (fPositionLock) {
list.addAll(fPositions);
}
}
/**
* Create a text presentation in the background.
*
* @param addedPositions the added positions
* @param removedPositions the removed positions
* @return the text presentation or <code>null</code>, if reconciliation should be canceled
*/
public TextPresentation createPresentation(List<Position> addedPositions, List<Position> removedPositions) {
SourceViewer sourceViewer = fSourceViewer;
YangPresentationReconciler presentationReconciler = fPresentationReconciler;
if (sourceViewer == null || presentationReconciler == null) {
return null;
}
if (isCanceled()) {
return null;
}
IDocument document = sourceViewer.getDocument();
if (document == null) {
return null;
}
int minStart = Integer.MAX_VALUE;
int maxEnd = Integer.MIN_VALUE;
for (int i = 0, n = removedPositions.size(); i < n; i++) {
Position position = removedPositions.get(i);
int offset = position.getOffset();
minStart = Math.min(minStart, offset);
maxEnd = Math.max(maxEnd, offset + position.getLength());
}
for (int i = 0, n = addedPositions.size(); i < n; i++) {
Position position = addedPositions.get(i);
int offset = position.getOffset();
minStart = Math.min(minStart, offset);
maxEnd = Math.max(maxEnd, offset + position.getLength());
}
if (minStart < maxEnd) {
try {
return presentationReconciler
.createRepairDescription(new Region(minStart, maxEnd - minStart), document);
} catch (RuntimeException e) {
// Assume concurrent modification from UI thread
}
}
return null;
}
/**
* Create a runnable for updating the presentation.
*
* @param textPresentation the text presentation
* @param addedPositions the added positions
* @param removedPositions the removed positions
* @return the runnable or <code>null</code>, if reconciliation should be canceled
*/
public Runnable createUpdateRunnable(final TextPresentation textPresentation, List<Position> addedPositions,
List<Position> removedPositions) {
if (fSourceViewer == null || textPresentation == null) {
return null;
}
// TODO: do clustering of positions and post multiple fast runnables
final HighlightedPosition[] added = new SemanticHighlightingManager.HighlightedPosition[addedPositions.size()];
addedPositions.toArray(added);
final SemanticHighlightingManager.HighlightedPosition[] removed = new SemanticHighlightingManager.HighlightedPosition[removedPositions
.size()];
removedPositions.toArray(removed);
if (isCanceled()) {
return null;
}
Runnable runnable = new Runnable() {
@Override
public void run() {
updatePresentation(textPresentation, added, removed);
}
};
return runnable;
}
/**
* Invalidate the presentation of the positions based on the given added positions and the
* existing deleted positions. Also unregisters the deleted positions from the document and
* patches the positions of this presenter.
*/
public void updatePresentation(TextPresentation textPresentation, HighlightedPosition[] addedPositions,
HighlightedPosition[] removedPositions) {
if (fSourceViewer == null) {
return;
}
// checkOrdering("added positions: ", Arrays.asList(addedPositions)); //$NON-NLS-1$
// checkOrdering("removed positions: ", Arrays.asList(removedPositions)); //$NON-NLS-1$
// checkOrdering("old positions: ", fPositions); //$NON-NLS-1$
// TODO: double-check consistency with document.getPositions(...)
// TODO: reuse removed positions
if (isCanceled()) {
return;
}
IDocument document = fSourceViewer.getDocument();
if (document == null) {
return;
}
String positionCategory = getPositionCategory();
List<HighlightedPosition> removedPositionsList = Arrays.asList(removedPositions);
try {
synchronized (fPositionLock) {
List<Position> oldPositions = fPositions;
int newSize = Math.max(fPositions.size() + addedPositions.length - removedPositions.length, 10);
/*
* The following loop is a kind of merge sort: it merges two List<Position>, each
* sorted by position.offset, into one new list. The first of the two is the
* previous list of positions (oldPositions), from which any deleted positions get
* removed on the fly. The second of two is the list of added positions. The result
* is stored in newPositions.
*/
List<Position> newPositions = new ArrayList<Position>(newSize);
Position position = null;
Position addedPosition = null;
for (int i = 0, j = 0, n = oldPositions.size(), m = addedPositions.length; i < n || position != null
|| j < m || addedPosition != null;) {
// loop variant: i + j < old(i + j)
// a) find the next non-deleted Position from the old list
while (position == null && i < n) {
position = oldPositions.get(i++);
if (position.isDeleted() || contain(removedPositionsList, position)) {
document.removePosition(positionCategory, position);
position = null;
}
}
// b) find the next Position from the added list
if (addedPosition == null && j < m) {
addedPosition = addedPositions[j++];
document.addPosition(positionCategory, addedPosition);
}
// c) merge: add the next of position/addedPosition with the lower offset
if (position != null) {
if (addedPosition != null) {
if (position.getOffset() <= addedPosition.getOffset()) {
newPositions.add(position);
position = null;
} else {
newPositions.add(addedPosition);
addedPosition = null;
}
} else {
newPositions.add(position);
position = null;
}
} else if (addedPosition != null) {
newPositions.add(addedPosition);
addedPosition = null;
}
}
fPositions = newPositions;
}
} catch (BadPositionCategoryException e) {
// Should not happen
YangEditorPlugin.log(e);
} catch (BadLocationException e) {
// Should not happen
YangEditorPlugin.log(e);
}
// checkOrdering("new positions: ", fPositions); //$NON-NLS-1$
if (textPresentation != null) {
fSourceViewer.changeTextPresentation(textPresentation, false);
} else {
fSourceViewer.invalidateTextPresentation();
}
}
// private void checkOrdering(String s, List positions) {
// Position previous= null;
// for (int i= 0, n= positions.size(); i < n; i++) {
// Position current= (Position) positions.get(i);
// if (previous != null && previous.getOffset() + previous.getLength() > current.getOffset())
// return;
// }
// }
/**
* Returns <code>true</code> iff the positions contain the position.
*
* @param positions the positions, must be ordered by offset but may overlap
* @param position the position
* @return <code>true</code> iff the positions contain the position
*/
private boolean contain(List<? extends Position> positions, Position position) {
return indexOf(positions, position) != -1;
}
/**
* Returns index of the position in the positions, <code>-1</code> if not found.
*
* @param positions the positions, must be ordered by offset but may overlap
* @param position the position
* @return the index
*/
private int indexOf(List<? extends Position> positions, Position position) {
int index = computeIndexAtOffset(positions, position.getOffset());
int size = positions.size();
while (index < size) {
if (positions.get(index) == position) {
return index;
}
index++;
}
return -1;
}
/**
* Insert the given position in <code>fPositions</code>, s.t. the offsets remain in linear
* order.
*
* @param position The position for insertion
*/
private void insertPosition(Position position) {
int i = computeIndexAfterOffset(fPositions, position.getOffset());
fPositions.add(i, position);
}
/**
* Returns the index of the first position with an offset greater than the given offset.
*
* @param positions the positions, must be ordered by offset and must not overlap
* @param offset the offset
* @return the index of the last position with an offset greater than the given offset
*/
private int computeIndexAfterOffset(List<Position> positions, int offset) {
int i = -1;
int j = positions.size();
while (j - i > 1) {
int k = (i + j) >> 1;
Position position = positions.get(k);
if (position.getOffset() > offset) {
j = k;
} else {
i = k;
}
}
return j;
}
/**
* Returns the index of the first position with an offset equal or greater than the given
* offset.
*/
private int computeIndexAtOffset(List<? extends Position> positions, int offset) {
int i = -1;
int j = positions.size();
while (j - i > 1) {
int k = (i + j) >> 1;
Position position = positions.get(k);
if (position.getOffset() >= offset) {
j = k;
} else {
i = k;
}
}
return j;
}
/*
* @see
* org.eclipse.jface.text.ITextPresentationListener#applyTextPresentation(org.eclipse.jface.
* text.TextPresentation)
*/
@Override
public void applyTextPresentation(TextPresentation textPresentation) {
IRegion region = textPresentation.getExtent();
int i = computeIndexAtOffset(fPositions, region.getOffset()), n = computeIndexAtOffset(fPositions,
region.getOffset() + region.getLength());
if (n - i > 2) {
List<StyleRange> ranges = new ArrayList<StyleRange>(n - i);
for (; i < n; i++) {
HighlightedPosition position = (HighlightedPosition) fPositions.get(i);
if (!position.isDeleted()) {
ranges.add(position.createStyleRange());
}
}
StyleRange[] array = new StyleRange[ranges.size()];
array = ranges.toArray(array);
textPresentation.replaceStyleRanges(array);
} else {
for (; i < n; i++) {
HighlightedPosition position = (HighlightedPosition) fPositions.get(i);
if (!position.isDeleted()) {
textPresentation.replaceStyleRange(position.createStyleRange());
}
}
}
}
/*
* @see
* org.eclipse.jface.text.ITextInputListener#inputDocumentAboutToBeChanged(org.eclipse.jface
* .text.IDocument, org.eclipse.jface.text.IDocument)
*/
@Override
public void inputDocumentAboutToBeChanged(IDocument oldInput, IDocument newInput) {
setCanceled(true);
releaseDocument(oldInput);
resetState();
}
/*
* @see
* org.eclipse.jface.text.ITextInputListener#inputDocumentChanged(org.eclipse.jface.text.IDocument
* , org.eclipse.jface.text.IDocument)
*/
@Override
public void inputDocumentChanged(IDocument oldInput, IDocument newInput) {
manageDocument(newInput);
}
/*
* @see
* org.eclipse.jface.text.IDocumentListener#documentAboutToBeChanged(org.eclipse.jface.text.
* DocumentEvent)
*/
@Override
public void documentAboutToBeChanged(DocumentEvent event) {
setCanceled(true);
}
/*
* @see
* org.eclipse.jface.text.IDocumentListener#documentChanged(org.eclipse.jface.text.DocumentEvent
* )
*/
@Override
public void documentChanged(DocumentEvent event) {
}
/**
* @return Returns <code>true</code> iff the current reconcile is canceled.
*/
public boolean isCanceled() {
IDocument document = fSourceViewer != null ? fSourceViewer.getDocument() : null;
if (document == null) {
return fIsCanceled;
}
synchronized (getLockObject(document)) {
return fIsCanceled;
}
}
/**
* Set whether or not the current reconcile is canceled.
*/
public void setCanceled(boolean isCanceled) {
IDocument document = fSourceViewer != null ? fSourceViewer.getDocument() : null;
if (document == null) {
fIsCanceled = isCanceled;
return;
}
synchronized (getLockObject(document)) {
fIsCanceled = isCanceled;
}
}
/**
* @param document the document
* @return the document's lock object
*/
private Object getLockObject(IDocument document) {
if (document instanceof ISynchronizable) {
Object lock = ((ISynchronizable) document).getLockObject();
if (lock != null) {
return lock;
}
}
return document;
}
/**
* Install this presenter on the given source viewer and background presentation reconciler.
*/
public void install(SourceViewer sourceViewer, YangPresentationReconciler backgroundPresentationReconciler) {
fSourceViewer = sourceViewer;
fPresentationReconciler = backgroundPresentationReconciler;
((YangSourceViewer) fSourceViewer).prependTextPresentationListener(this);
fSourceViewer.addTextInputListener(this);
manageDocument(fSourceViewer.getDocument());
}
/**
* Uninstall this presenter.
*/
public void uninstall() {
setCanceled(true);
if (fSourceViewer != null) {
fSourceViewer.removeTextPresentationListener(this);
releaseDocument(fSourceViewer.getDocument());
invalidateTextPresentation();
resetState();
fSourceViewer.removeTextInputListener(this);
fSourceViewer = null;
}
}
/**
* Invalidate text presentation of positions with the given highlighting.
*
* @param highlighting The highlighting
*/
public void highlightingStyleChanged(Highlighting highlighting) {
for (int i = 0, n = fPositions.size(); i < n; i++) {
HighlightedPosition position = (HighlightedPosition) fPositions.get(i);
if (position.getHighlighting() == highlighting) {
fSourceViewer.invalidateTextPresentation(position.getOffset(), position.getLength());
}
}
}
/**
* Invalidate text presentation of all positions.
*/
private void invalidateTextPresentation() {
for (int i = 0, n = fPositions.size(); i < n; i++) {
Position position = fPositions.get(i);
fSourceViewer.invalidateTextPresentation(position.getOffset(), position.getLength());
}
}
/**
* Add a position with the given range and highlighting unconditionally, only from UI thread.
* The position will also be registered on the document. The text presentation is not
* invalidated.
*
* @param offset The range offset
* @param length The range length
* @param highlighting the highlighting
*/
private void addPositionFromUI(int offset, int length, Highlighting highlighting) {
Position position = createHighlightedPosition(offset, length, highlighting);
synchronized (fPositionLock) {
insertPosition(position);
}
IDocument document = fSourceViewer.getDocument();
if (document == null) {
return;
}
String positionCategory = getPositionCategory();
try {
document.addPosition(positionCategory, position);
} catch (BadLocationException e) {
// Should not happen
YangEditorPlugin.log(e);
} catch (BadPositionCategoryException e) {
// Should not happen
YangEditorPlugin.log(e);
}
}
/**
* Reset to initial state.
*/
private void resetState() {
synchronized (fPositionLock) {
fPositions.clear();
}
}
/**
* Start managing the given document.
*
* @param document The document
*/
private void manageDocument(IDocument document) {
if (document != null) {
document.addPositionCategory(getPositionCategory());
document.addPositionUpdater(fPositionUpdater);
document.addDocumentListener(this);
}
}
/**
* Stop managing the given document.
*
* @param document The document
*/
private void releaseDocument(IDocument document) {
if (document != null) {
document.removeDocumentListener(this);
document.removePositionUpdater(fPositionUpdater);
try {
document.removePositionCategory(getPositionCategory());
} catch (BadPositionCategoryException e) {
// Should not happen
YangEditorPlugin.log(e);
}
}
}
/**
* @return The semantic reconciler position's category.
*/
private String getPositionCategory() {
return toString();
}
}