EclipseCollabHyperlinkDetector.java

/****************************************************************************
 * Copyright (c) 2007 Composent, 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
 *
 * Contributors:
 *    Composent, Inc. - initial API and implementation
 *****************************************************************************/
package org.eclipse.ecf.internal.example.collab.ui.hyperlink;

import org.eclipse.ecf.example.collab.share.EclipseCollabSharedObject.SharedMarker;
import org.eclipse.jface.text.*;
import org.eclipse.jface.text.hyperlink.AbstractHyperlinkDetector;
import org.eclipse.jface.text.hyperlink.IHyperlink;

public class EclipseCollabHyperlinkDetector extends AbstractHyperlinkDetector {

	public static final String SHARE_FILE_HYPERLINK_END = "/>"; //$NON-NLS-1$
	public static final String SHARE_FILE_HYPERLINK_START = "<open file=\""; //$NON-NLS-1$
	public static final String SHARE_FILE_HYPERLINK_SELECTION = " selection="; //$NON-NLS-1$

	/* (non-Javadoc)
	 * @see org.eclipse.jface.text.hyperlink.IHyperlinkDetector#detectHyperlinks(org.eclipse.jface.text.ITextViewer, org.eclipse.jface.text.IRegion, boolean)
	 */
	public IHyperlink[] detectHyperlinks(ITextViewer textViewer, IRegion region, boolean canShowMultipleHyperlinks) {

		if (region == null || textViewer == null)
			return null;

		final IDocument document = textViewer.getDocument();
		if (document == null)
			return null;

		final int offset = region.getOffset();

		IRegion lineInfo;
		String line;
		try {
			lineInfo = document.getLineInformationOfOffset(offset);
			line = document.get(lineInfo.getOffset(), lineInfo.getLength());
		} catch (final BadLocationException ex) {
			return null;
		}

		final IRegion detectedRegion = detectSubRegion(lineInfo, line);
		if (detectedRegion == null)
			return null;

		final int detectedStart = detectedRegion.getOffset() - lineInfo.getOffset();
		final String substring = line.substring(detectedStart, detectedStart + detectedRegion.getLength());
		final String fileName = detectFileName(substring);
		if (fileName == null)
			return null;

		final Selection selection = detectSelection(substring);

		return new IHyperlink[] {new EclipseCollabHyperlink(detectedRegion, fileName, selection)};

	}

	private Selection detectSelection(String linkString) {
		final int beginIndex = linkString.indexOf(SHARE_FILE_HYPERLINK_SELECTION);
		if (beginIndex == -1)
			return null;
		final int endIndex = linkString.indexOf(SHARE_FILE_HYPERLINK_END);
		if (endIndex == -1)
			return null;
		// should have syntax start-end
		final String selection = linkString.substring(beginIndex + SHARE_FILE_HYPERLINK_SELECTION.length(), endIndex);
		final int dashIndex = selection.indexOf("-"); //$NON-NLS-1$
		if (dashIndex == -1)
			return null;
		try {
			final int start = Integer.parseInt(selection.substring(0, dashIndex));
			final int end = Integer.parseInt(selection.substring(dashIndex + 1));
			return new Selection(start, end);
		} catch (final NumberFormatException e) {
			return null;
		}
	}

	class Selection {
		int start;
		int end;

		public Selection(int start, int end) {
			this.start = start;
			this.end = end;
		}

		public int getStart() {
			return start;
		}

		public int getEnd() {
			return end;
		}
	}

	private String detectFileName(String substring) {
		final int startIndex = substring.indexOf("\""); //$NON-NLS-1$
		if (startIndex == -1)
			return null;
		final int endIndex = substring.indexOf("\"", startIndex + 1); //$NON-NLS-1$
		if (endIndex == -1)
			return null;
		return substring.substring(startIndex + 1, endIndex);
	}

	protected IRegion detectSubRegion(IRegion lineInfo, String fromLine) {
		final int startIndex = fromLine.indexOf(SHARE_FILE_HYPERLINK_START);
		if (startIndex == -1)
			return null;
		// got one...look for terminator after
		final int endIndex = fromLine.indexOf(SHARE_FILE_HYPERLINK_END, startIndex);
		if (endIndex == -1)
			return null;
		return new Region(lineInfo.getOffset() + startIndex, (endIndex - startIndex) + SHARE_FILE_HYPERLINK_END.length());
	}

	public static String createDisplayStringForEditorOpen(String resourceName, SharedMarker marker) {
		final StringBuffer se = new StringBuffer(EclipseCollabHyperlinkDetector.SHARE_FILE_HYPERLINK_START);
		se.append(resourceName).append("\""); //$NON-NLS-1$
		if (marker != null) {
			final int start = marker.getOffset().intValue();
			final int length = marker.getLength().intValue();
			if (length > 0) {
				se.append(EclipseCollabHyperlinkDetector.SHARE_FILE_HYPERLINK_SELECTION);
				se.append(start).append("-").append(start + length); //$NON-NLS-1$
			}
		}
		se.append(EclipseCollabHyperlinkDetector.SHARE_FILE_HYPERLINK_END);
		return se.toString();
	}

}