/*******************************************************************************
* Copyright (c) 2007, 2011 David Green 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:
* David Green - initial API and implementation
*******************************************************************************/
package org.eclipse.mylyn.wikitext.ui.viewer;
import java.util.regex.Pattern;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.text.DefaultInformationControl;
import org.eclipse.jface.text.TextPresentation;
import org.eclipse.mylyn.internal.wikitext.ui.viewer.HtmlTextPresentationParser;
import org.eclipse.swt.graphics.Drawable;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.widgets.Display;
/**
* An information presenter that supports HTML markup. Uses the {@link HtmlTextPresentationParser HTML parser} to parse
* the HTML to readable text, and creates the appropriate corresponding {@link TextPresentation text presentation}.
*
* @author David Green
* @since 1.0
*/
public class HtmlTextPresenter implements DefaultInformationControl.IInformationPresenter,
DefaultInformationControl.IInformationPresenterExtension {
private static Pattern HTML_OPEN_TAG_PATTERN = Pattern.compile("<html", Pattern.CASE_INSENSITIVE); //$NON-NLS-1$
@SuppressWarnings("deprecation")
public String updatePresentation(Display display, String hoverInfo, TextPresentation presentation, int maxWidth,
int maxHeight) {
return updatePresentation((Drawable) display, hoverInfo, presentation, maxWidth, maxHeight);
}
public String updatePresentation(Drawable drawable, String hoverInfo, TextPresentation presentation, int maxWidth,
int maxHeight) {
if (hoverInfo == null || hoverInfo.length() == 0) {
return hoverInfo;
}
HtmlTextPresentationParser parser = new HtmlTextPresentationParser();
parser.setPresentation(presentation);
parser.setDefaultFont(JFaceResources.getFontRegistry().defaultFont());
String html = hoverInfo;
if (!HTML_OPEN_TAG_PATTERN.matcher(html).find()) {
html = "<html><body>" + html + "</body></html>"; //$NON-NLS-1$ //$NON-NLS-2$
}
GC gc = new GC(drawable);
try {
html = html.replaceAll("<br>", "<br/>"); //$NON-NLS-1$ //$NON-NLS-2$
parser.setMaxWidth(maxWidth);
parser.setGC(gc);
parser.parse(html);
return parser.getText();
} catch (Exception e) {
return exceptionToHoverInfo(hoverInfo, presentation, e);
} finally {
gc.dispose();
}
}
protected String exceptionToHoverInfo(String hoverInfo, TextPresentation presentation, Exception e) {
presentation.clear();
return hoverInfo;
}
}