BundleTypeCompletionProposal.java

/*******************************************************************************
 * Copyright (c) 2009, 2010 SpringSource, a divison of VMware, Inc.
 * 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:
 *     SpringSource, a division of VMware, Inc. - initial API and implementation
 *******************************************************************************/
package org.eclipse.virgo.ide.ui.editors.text;

import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.jdt.internal.ui.JavaPlugin;
import org.eclipse.jface.internal.text.html.BrowserInformationControl;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.text.AbstractReusableInformationControlCreator;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IInformationControl;
import org.eclipse.jface.text.IInformationControlCreator;
import org.eclipse.jface.text.contentassist.ICompletionProposal;
import org.eclipse.jface.text.contentassist.ICompletionProposalExtension;
import org.eclipse.jface.text.contentassist.ICompletionProposalExtension3;
import org.eclipse.jface.text.contentassist.ICompletionProposalExtension5;
import org.eclipse.jface.text.contentassist.IContextInformation;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.editors.text.EditorsUI;

/**
 * @author Christian Dupuis
 * @author Steffen Pingel
 */
public class BundleTypeCompletionProposal implements ICompletionProposal, ICompletionProposalExtension,
		ICompletionProposalExtension3, ICompletionProposalExtension5 {

	protected String fReplacementString;

	protected Image fImage;

	protected String fDisplayString;

	protected int fBeginInsertPoint;

	protected int fLength;

	protected String fAdditionalInfo;

	private IInformationControlCreator fCreator;

	public BundleTypeCompletionProposal(String replacementString, Image image, String displayString) {
		this(replacementString, image, displayString, 0, 0);
	}

	public BundleTypeCompletionProposal(String replacementString, Image image, String displayString, int startOffset,
			int length) {
		Assert.isNotNull(replacementString);

		fReplacementString = replacementString;
		fImage = image;
		fDisplayString = displayString;
		fBeginInsertPoint = startOffset;
		fLength = length;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.jface.text.contentassist.ICompletionProposal#apply(org.eclipse
	 * .jface.text.IDocument)
	 */
	public void apply(IDocument document) {
		if (fLength == -1) {
			String current = document.get();
			fLength = current.length();
		}
		try {
			document.replace(fBeginInsertPoint, fLength, fReplacementString);
		}
		catch (BadLocationException e) {
			// DEBUG
			// e.printStackTrace();
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @seeorg.eclipse.jface.text.contentassist.ICompletionProposal#
	 * getAdditionalProposalInfo()
	 */
	public String getAdditionalProposalInfo() {
		// No additional proposal information
		return null;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @seeorg.eclipse.jface.text.contentassist.ICompletionProposal#
	 * getContextInformation()
	 */
	public IContextInformation getContextInformation() {
		// No context information
		return null;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.jface.text.contentassist.ICompletionProposal#getDisplayString
	 * ()
	 */
	public String getDisplayString() {
		return fDisplayString;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.text.contentassist.ICompletionProposal#getImage()
	 */
	public Image getImage() {
		return fImage;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.jface.text.contentassist.ICompletionProposal#getSelection
	 * (org.eclipse.jface.text.IDocument)
	 */
	public Point getSelection(IDocument document) {
		if (fReplacementString.equals("\"\"")) {
			return new Point(fBeginInsertPoint + 1, 0);
		}
		return new Point(fBeginInsertPoint + fReplacementString.length(), 0);
	}

	/**
	 * @return
	 */
	public String getReplacementString() {
		return fReplacementString;
	}

	public Object getAdditionalProposalInfo(IProgressMonitor monitor) {
		return fAdditionalInfo;
	}

	public void setAdditionalProposalInfo(String info) {
		fAdditionalInfo = info;
	}

	public IInformationControlCreator getInformationControlCreator() {
		Shell shell = JavaPlugin.getActiveWorkbenchShell();
		if (shell == null || !BrowserInformationControl.isAvailable(shell)) {
			return null;
		}

		if (fCreator == null) {
			fCreator = new AbstractReusableInformationControlCreator() {

				/*
				 * @seeorg.eclipse.jdt.internal.ui.text.java.hover.
				 * AbstractReusableInformationControlCreator
				 * #doCreateInformationControl(org.eclipse.swt.widgets.Shell)
				 */
				public IInformationControl doCreateInformationControl(Shell parent) {
					return new BrowserInformationControl(parent, JFaceResources.DIALOG_FONT,
							EditorsUI.getTooltipAffordanceString());
				}
			};
		}
		return fCreator;
	}

	public int getPrefixCompletionStart(IDocument document, int completionOffset) {
		return fBeginInsertPoint;
	}

	public CharSequence getPrefixCompletionText(IDocument document, int completionOffset) {
		return fReplacementString;
	}

	public void apply(IDocument document, char trigger, int offset) {
		if (fLength == -1) {
			String current = document.get();
			fLength = current.length();
		}
		try {
			document.replace(fBeginInsertPoint, fLength, fReplacementString);
		}
		catch (BadLocationException e) {
			// DEBUG
			// e.printStackTrace();
		}
	}

	public int getContextInformationPosition() {
		return fBeginInsertPoint;
	}

	public char[] getTriggerCharacters() {
		return new char[0];
	}

	public boolean isValidFor(IDocument document, int offset) {
		if (offset < fBeginInsertPoint) {
			return false;
		}
		int newLength = offset - fBeginInsertPoint;
		int delta = newLength - fLength;
		fLength = delta + fLength;

		return startsWith(document, offset, fDisplayString);
	}

	// code is borrowed from JavaCompletionProposal
	protected boolean startsWith(IDocument document, int offset, String word) {
		int wordLength = word == null ? 0 : word.length();
		if (offset > fBeginInsertPoint + wordLength) {
			return false;
		}

		try {
			int length = offset - fBeginInsertPoint;
			String start = document.get(fBeginInsertPoint, length);
			// Remove " for comparison
			return word != null && word.substring(0, start.length()).equalsIgnoreCase(start);
		}
		catch (BadLocationException x) {
		}

		return false;
	}
}