/*******************************************************************************
* Copyright (c) 2000, 2008 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.jdt.internal.ui.text.template.contentassist;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Point;
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.contentassist.ICompletionProposal;
import org.eclipse.jface.text.contentassist.ICompletionProposalExtension2;
import org.eclipse.jface.text.contentassist.IContextInformation;
/**
* Global state for templates. Selecting a proposal for the master template variable
* will cause the value (and the proposals) for the slave variables to change.
*
* @see MultiVariable
*/
public class MultiVariableGuess {
/**
* Implementation of the <code>ICompletionProposal</code> interface and extension.
*/
private static class Proposal implements ICompletionProposal, ICompletionProposalExtension2 {
/** The string to be displayed in the completion proposal popup */
private String fDisplayString;
/** The replacement string */
String fReplacementString;
/** The replacement offset */
private int fReplacementOffset;
/** The replacement length */
private int fReplacementLength;
/** The cursor position after this proposal has been applied */
private int fCursorPosition;
/** The image to be displayed in the completion proposal popup */
private Image fImage;
/** The context information of this proposal */
private IContextInformation fContextInformation;
/** The additional info of this proposal */
private 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 replacementOffset the offset of the text to be replaced
* @param replacementLength the length of the text to be replaced
* @param cursorPosition the position of the cursor following the insert relative to replacementOffset
*/
public Proposal(String replacementString, int replacementOffset, int replacementLength, int cursorPosition) {
this(replacementString, replacementOffset, replacementLength, 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 replacementOffset the offset of the text to be replaced
* @param replacementLength the length 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 Proposal(String replacementString, int replacementOffset, int replacementLength, int cursorPosition, Image image, String displayString, IContextInformation contextInformation, String additionalProposalInfo) {
Assert.isNotNull(replacementString);
Assert.isTrue(replacementOffset >= 0);
Assert.isTrue(replacementLength >= 0);
Assert.isTrue(cursorPosition >= 0);
fReplacementString= replacementString;
fReplacementOffset= replacementOffset;
fReplacementLength= replacementLength;
fCursorPosition= cursorPosition;
fImage= image;
fDisplayString= displayString;
fContextInformation= contextInformation;
fAdditionalProposalInfo= additionalProposalInfo;
}
/*
* @see ICompletionProposal#apply(IDocument)
*/
public void apply(IDocument document) {
try {
document.replace(fReplacementOffset, fReplacementLength, fReplacementString);
} catch (BadLocationException x) {
// ignore
}
}
/*
* @see ICompletionProposal#getSelection(IDocument)
*/
public Point getSelection(IDocument document) {
return new Point(fReplacementOffset + fCursorPosition, 0);
}
/*
* @see ICompletionProposal#getContextInformation()
*/
public IContextInformation getContextInformation() {
return fContextInformation;
}
/*
* @see ICompletionProposal#getImage()
*/
public Image getImage() {
return fImage;
}
/*
* @see ICompletionProposal#getDisplayString()
*/
public String getDisplayString() {
if (fDisplayString != null)
return fDisplayString;
return fReplacementString;
}
/*
* @see ICompletionProposal#getAdditionalProposalInfo()
*/
public String getAdditionalProposalInfo() {
return fAdditionalProposalInfo;
}
/*
* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#apply(org.eclipse.jface.text.ITextViewer, char, int, int)
*/
public void apply(ITextViewer viewer, char trigger, int stateMask, int offset) {
apply(viewer.getDocument());
}
/*
* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#selected(org.eclipse.jface.text.ITextViewer, boolean)
*/
public void selected(ITextViewer viewer, boolean smartToggle) {
}
/*
* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#unselected(org.eclipse.jface.text.ITextViewer)
*/
public void unselected(ITextViewer viewer) {
}
/*
* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#validate(org.eclipse.jface.text.IDocument, int, org.eclipse.jface.text.DocumentEvent)
*/
public boolean validate(IDocument document, int offset, DocumentEvent event) {
try {
String content= document.get(fReplacementOffset, fReplacementLength);
if (content.startsWith(fReplacementString))
return true;
} catch (BadLocationException e) {
// ignore concurrently modified document
}
return false;
}
}
private final Map fDependencies= new HashMap();
private final Map fBackwardDeps= new HashMap();
private final Map fPositions= new HashMap();
public MultiVariableGuess() {
}
public ICompletionProposal[] getProposals(final MultiVariable variable, int offset, int length) {
MultiVariable master= (MultiVariable) fBackwardDeps.get(variable);
Object[] choices;
if (master == null)
choices= variable.getChoices();
else
choices= variable.getChoices(master.getCurrentChoice());
if (choices == null)
return null;
if (fDependencies.containsKey(variable)) {
ICompletionProposal[] ret= new ICompletionProposal[choices.length];
for (int i= 0; i < ret.length; i++) {
final Object choice= choices[i];
ret[i]= new Proposal(variable.toString(choice), offset, length, offset + length) {
public void apply(IDocument document) {
super.apply(document);
Object oldChoice= variable.getCurrentChoice();
variable.setCurrentChoice(choice);
updateSlaves(variable, document, oldChoice);
}
};
}
return ret;
} else {
if (choices.length < 2)
return null;
ICompletionProposal[] ret= new ICompletionProposal[choices.length];
for (int i= 0; i < ret.length; i++)
ret[i]= new Proposal(variable.toString(choices[i]), offset, length, offset + length);
return ret;
}
}
private void updateSlaves(MultiVariable variable, IDocument document, Object oldChoice) {
Object choice= variable.getCurrentChoice();
if (!oldChoice.equals(choice)) {
Set slaves= (Set) fDependencies.get(variable);
for (Iterator it= slaves.iterator(); it.hasNext();) {
MultiVariable slave= (MultiVariable) it.next();
VariablePosition pos= (VariablePosition) fPositions.get(slave);
Object slavesOldChoice= slave.getCurrentChoice();
slave.setKey(choice); // resets the current choice
try {
document.replace(pos.getOffset(), pos.getLength(), slave.getDefaultValue());
} catch (BadLocationException x) {
// ignore and continue
}
// handle slaves recursively
if (fDependencies.containsKey(slave))
updateSlaves(slave, document, slavesOldChoice);
}
}
}
/**
* @param position
*/
public void addSlave(VariablePosition position) {
fPositions.put(position.getVariable(), position);
}
/**
* @param master
* @param slave
* @since 3.3
*/
public void addDependency(MultiVariable master, MultiVariable slave) {
// check for cycles and multi-slaves
if (fBackwardDeps.containsKey(slave))
throw new IllegalArgumentException("slave can only serve one master"); //$NON-NLS-1$
Object parent= master;
while (parent != null) {
parent= fBackwardDeps.get(parent);
if (parent == slave)
throw new IllegalArgumentException("cycle detected"); //$NON-NLS-1$
}
Set slaves= (Set) fDependencies.get(master);
if (slaves == null) {
slaves= new HashSet();
fDependencies.put(master, slaves);
}
fBackwardDeps.put(slave, master);
slaves.add(slave);
}
}