/*=============================================================================#
# Copyright (c) 2000-2016 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 de.walware.ecommons.text.ui;
import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.DocumentEvent;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.Position;
import org.eclipse.jface.text.contentassist.ICompletionProposal;
import org.eclipse.jface.text.contentassist.ICompletionProposalExtension;
import org.eclipse.jface.text.contentassist.ICompletionProposalExtension2;
import org.eclipse.jface.text.contentassist.IContextInformation;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Point;
/**
* An enhanced implementation of the <code>ICompletionProposal</code> interface implementing
* the extension interfaces 1-2.
* <p>
* It uses a position to track its replacement offset and length. The position must be set up
* externally.</p>
*/
public final class PositionBasedCompletionProposal implements ICompletionProposal, ICompletionProposalExtension, ICompletionProposalExtension2 {
/** The string to be displayed in the completion proposal popup */
private final String fDisplayString;
/** The replacement string */
private final String fReplacementString;
/** The replacement position. */
private final Position fReplacementPosition;
/** The cursor position after this proposal has been applied */
private final int fCursorPosition;
/** The image to be displayed in the completion proposal popup */
private final Image fImage;
/** The context information of this proposal */
private final IContextInformation fContextInformation;
/** The additional info of this proposal */
private final String fAdditionalProposalInfo;
/**
* Creates a new completion proposal based on the provided information. The replacement string is
* considered being the display string too. All remaining fields are set to <code>null</code>.
*
* @param replacementString the actual string to be inserted into the document
* @param replacementPosition the position of the text to be replaced
* @param cursorPosition the position of the cursor following the insert relative to replacementOffset
*/
public PositionBasedCompletionProposal(final String replacementString, final Position replacementPosition, final int cursorPosition) {
this(replacementString, replacementPosition, cursorPosition, null, null, null, null);
}
/**
* Creates a new completion proposal. All fields are initialized based on the provided information.
*
* @param replacementString the actual string to be inserted into the document
* @param replacementPosition the position of the text to be replaced
* @param cursorPosition the position of the cursor following the insert relative to replacementOffset
* @param image the image to display for this proposal
* @param displayString the string to be displayed for the proposal
* @param contextInformation the context information associated with this proposal
* @param additionalProposalInfo the additional information associated with this proposal
*/
public PositionBasedCompletionProposal(final String replacementString, final Position replacementPosition, final int cursorPosition, final Image image, final String displayString, final IContextInformation contextInformation, final String additionalProposalInfo) {
Assert.isNotNull(replacementString);
Assert.isTrue(replacementPosition != null);
fReplacementString = replacementString;
fReplacementPosition = replacementPosition;
fCursorPosition = cursorPosition;
fImage = image;
fDisplayString = displayString;
fContextInformation = contextInformation;
fAdditionalProposalInfo = additionalProposalInfo;
}
/**
* {@inheritDoc}
*/
@Override
public void selected(final ITextViewer viewer, final boolean smartToggle) {
}
/**
* {@inheritDoc}
*/
@Override
public void unselected(final ITextViewer viewer) {
}
/**
* {@inheritDoc}
*/
@Override
public boolean isValidFor(final IDocument document, final int offset) {
// not called anymore
return false;
}
/**
* {@inheritDoc}
*/
@Override
public boolean validate(final IDocument document, final int offset, final DocumentEvent event) {
try {
final String content = document.get(fReplacementPosition.getOffset(), offset - fReplacementPosition.getOffset());
if (fReplacementString.startsWith(content)) {
return true;
}
} catch (final BadLocationException e) {
// ignore concurrently modified document
}
return false;
}
/**
* {@inheritDoc}
*/
@Override
public char[] getTriggerCharacters() {
return null;
}
/**
* {@inheritDoc}
*/
@Override
public Image getImage() {
return fImage;
}
/**
* {@inheritDoc}
*/
@Override
public String getDisplayString() {
if (fDisplayString != null) {
return fDisplayString;
}
return fReplacementString;
}
/**
* {@inheritDoc}
*/
@Override
public String getAdditionalProposalInfo() {
return fAdditionalProposalInfo;
}
@Override
public void apply(final IDocument document, final char trigger, final int offset) {
}
@Override
public void apply(final IDocument document) {
try {
document.replace(fReplacementPosition.getOffset(), fReplacementPosition.getLength(), fReplacementString);
} catch (final BadLocationException x) {
// ignore
}
}
/**
* {@inheritDoc}
*/
@Override
public void apply(final ITextViewer viewer, final char trigger, final int stateMask, final int offset) {
apply(viewer.getDocument());
}
/**
* {@inheritDoc}
*/
@Override
public Point getSelection(final IDocument document) {
return new Point(fReplacementPosition.getOffset() + fCursorPosition, 0);
}
/**
* {@inheritDoc}
*/
@Override
public IContextInformation getContextInformation() {
return fContextInformation;
}
/**
* {@inheritDoc}
*/
@Override
public int getContextInformationPosition() {
return fReplacementPosition.getOffset();
}
}