/*******************************************************************************
 * Copyright (c) 2006 The Regents of the University of California. 
 * This material was produced under U.S. Government contract W-7405-ENG-36 
 * for Los Alamos National Laboratory, which is operated by the University 
 * of California for the U.S. Department of Energy. The U.S. Government has 
 * rights to use, reproduce, and distribute this software. NEITHER THE 
 * GOVERNMENT NOR THE UNIVERSITY MAKES ANY WARRANTY, EXPRESS OR IMPLIED, OR 
 * ASSUMES ANY LIABILITY FOR THE USE OF THIS SOFTWARE. If software is modified 
 * to produce derivative works, such modified software should be clearly marked, 
 * so as not to confuse it with the version available from LANL.
 * 
 * Additionally, 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
 * 
 * LA-CC 04-115
 *******************************************************************************/
package org.eclipse.ptp.utils.ui.swt;

import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.ptp.utils.ui.PixelConverter;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;

public class SWTUtil {
	/**
	 * Creates and returns a new push button with the given label and/or image.
	 * 
	 * @param parent
	 *            parent control
	 * @param label
	 *            button label or <code>null</code>
	 * @param image
	 *            image of <code>null</code>
	 * 
	 * @return a new push button
	 */
	public static Button createPushButton(Composite parent, String label,
			Image image) {
		Button button = new Button(parent, SWT.PUSH);
		button.setFont(parent.getFont());
		if (image != null) {
			button.setImage(image);
		}
		if (label != null) {
			button.setText(label);
		}
		GridData gd = new GridData();
		button.setLayoutData(gd);
		setButtonDimensionHint(button);
		return button;
	}

	/**
	 * Sets width and height hint for the button control. <b>Note:</b> This is
	 * a NOP if the button's layout data is not an instance of
	 * <code>GridData</code>.
	 * 
	 * @param the
	 *            button for which to set the dimension hint
	 */
	public static void setButtonDimensionHint(Button button) {
		Assert.isNotNull(button);
		Object gd = button.getLayoutData();
		if (gd instanceof GridData) {
			((GridData) gd).widthHint = getButtonWidthHint(button);
			((GridData) gd).horizontalAlignment = GridData.FILL;
		}
	}

	/**
	 * Returns a width hint for a button control.
	 */
	public static int getButtonWidthHint(Button button) {
		button.setFont(JFaceResources.getDialogFont());
		PixelConverter converter = new PixelConverter(button);
		int widthHint = converter.convertHorizontalDLUsToPixels(IDialogConstants.BUTTON_WIDTH);
		return Math.max(widthHint, button.computeSize(SWT.DEFAULT, SWT.DEFAULT,
				true).x);
	}
}