/*******************************************************************************
 *  Copyright (c) 2007, 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.equinox.internal.p2.ui.sdk.scheduler;

import org.eclipse.jface.action.*;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.CLabel;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Listener;

/**
 * @since 3.4
 */
public class StatusLineCLabelContribution extends ContributionItem {

	public final static int DEFAULT_CHAR_WIDTH = 40;

	private int charWidth;
	private CLabel label;
	private Image image;
	private String text = ""; //$NON-NLS-1$
	private int widthHint = -1;
	private int heightHint = -1;

	private Listener listener;
	private int eventType;
	private String tooltip;

	public StatusLineCLabelContribution(String id, int charWidth) {
		super(id);
		this.charWidth = charWidth;
		setVisible(false); // no text to start with
	}

	public void fill(Composite parent) {
		label = new CLabel(parent, SWT.DEFAULT);
		StatusLineLayoutData statusLineLayoutData = new StatusLineLayoutData();

		if (widthHint < 0) {
			GC gc = new GC(parent);
			gc.setFont(parent.getFont());
			FontMetrics fm = gc.getFontMetrics();
			widthHint = fm.getAverageCharWidth() * charWidth;
			heightHint = fm.getHeight();
			gc.dispose();
		}

		statusLineLayoutData.widthHint = widthHint;
		label.setLayoutData(statusLineLayoutData);
		label.setText(text);
		label.setImage(image);
		if (listener != null) {
			label.addListener(eventType, listener);
		}
		if (tooltip != null) {
			label.setToolTipText(tooltip);
		}

		statusLineLayoutData = new StatusLineLayoutData();
		statusLineLayoutData.heightHint = heightHint;
	}

	public void addListener(int type, Listener labelListener) {
		this.eventType = type;
		this.listener = labelListener;
	}

	public void setText(String text) {
		if (text == null)
			throw new NullPointerException();

		this.text = text;

		if (label != null && !label.isDisposed())
			label.setText(this.text);

		if (this.text.length() == 0) {
			if (isVisible()) {
				setVisible(false);
				IContributionManager contributionManager = getParent();

				if (contributionManager != null)
					contributionManager.update(true);
			}
		} else {
			if (!isVisible()) {
				setVisible(true);
				IContributionManager contributionManager = getParent();

				if (contributionManager != null)
					contributionManager.update(true);
			}
		}
	}

	public void setTooltip(String tooltip) {
		if (tooltip == null)
			throw new NullPointerException();

		this.tooltip = tooltip;

		if (label != null && !label.isDisposed()) {
			label.setToolTipText(this.tooltip);
		}
	}

	public void setImage(Image image) {
		if (image == null)
			throw new NullPointerException();

		this.image = image;

		if (label != null && !label.isDisposed())
			label.setImage(this.image);

		if (!isVisible()) {
			setVisible(true);
			IContributionManager contributionManager = getParent();

			if (contributionManager != null)
				contributionManager.update(true);
		}
	}
}