/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright (c) 2009, 2012, Oracle and/or its affiliates. All rights reserved.

 */

package com.oracle.solaris.vp.util.swing;

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

@SuppressWarnings({"serial"})

public class GradientPanel extends JPanel {

    //

    // Enums

    //

    public enum Direction {

	NORTHWEST, NORTH, NORTHEAST, EAST,

	SOUTHEAST, SOUTH, SOUTHWEST, WEST,

    }

    //

    // Static methods

    //

    private static final Direction _DIRECTION = Direction.SOUTH;

    //

    // Instance data

    //

    private Direction direction;

    private Color startColor;

    private Color endColor;

    //

    // Constructors

    //

    public GradientPanel(Direction direction, Color startColor,

	Color endColor) {

	this.direction = direction;

	this.startColor = startColor;

	this.endColor = endColor;

    }

    public GradientPanel(Color startColor, Color endColor) {

	this(_DIRECTION, startColor, endColor);

    }

    public GradientPanel() {

	this(_DIRECTION, null, null);

    }

    //

    // GradientPanel methods

    //

    public Direction getDirection() {

	return direction;

    }

    public Color getStartColor() {

	return startColor;

    }

    public Color getEndColor() {

	return endColor;

    }

    public void setDirection(Direction direction) {

	this.direction = direction;

	repaint();

    }

    public void setStartColor(Color startColor) {

	this.startColor = startColor;

	repaint();

    }

    public void setEndColor(Color endColor) {

	this.endColor = endColor;

	repaint();

    }

    //

    // JComponent methods

    //

    @Override

    protected void paintComponent(Graphics g) {

	Color startColor = getStartColor();

	Color endColor = getEndColor();

	if (startColor == null) {

	    startColor = getBackground();

	}

	if (endColor == null) {

	    endColor = getBackground();

	}

	Graphics2D g2 = (Graphics2D)g;

	int w = getWidth();

	int h = getHeight();

	int startX, startY, endX, endY;

	switch (getDirection()) {

	    case NORTHWEST:

		startX = w;

		startY = h;

		endX = 0;

		endY = 0;

		break;

	    case NORTH:

		startX = 0;

		startY = h;

		endX = 0;

		endY = 0;

		break;

	    case NORTHEAST:

		startX = 0;

		startY = h;

		endX = w;

		endY = 0;

		break;

	    case EAST:

		startX = 0;

		startY = 0;

		endX = w;

		endY = 0;

		break;

	    case SOUTHWEST:

		startX = w;

		startY = 0;

		endX = 0;

		endY = h;

		break;

	    default:

	    case SOUTH:

		startX = 0;

		startY = 0;

		endX = 0;

		endY = h;

		break;

	    case SOUTHEAST:

		startX = 0;

		startY = 0;

		endX = w;

		endY = h;

		break;

	    case WEST:

		startX = w;

		startY = 0;

		endX = 0;

		endY = 0;

		break;

	}

	GradientPaint gradient = new GradientPaint(

	    startX, startY, startColor, endX, endY, endColor, true);

	g2.setPaint(gradient);

	g2.fillRect(0, 0, w, h);

    }

    //

    // Static methods

    //

    /**

     * Unit test/example.

     */

    public static void main(String[] args) {

	Color start = new Color(112, 130, 144);

	Color end = new Color(64, 82, 101);

	final GradientPanel panel = new GradientPanel(start, end);

	ItemListener listener = new ItemListener() {

	    @Override

	    public void itemStateChanged(ItemEvent e) {

		int change = e.getStateChange();

		if (change == ItemEvent.SELECTED) {

		    panel.setDirection((Direction)e.getItem());

		}

	    }

	};

	JComboBox combo = new JComboBox(Direction.values());

	combo.addItemListener(listener);

	combo.setSelectedIndex(-1);

	combo.setSelectedIndex(0);

	JFrame f = new JFrame();

	panel.add(combo);

	Container c = f.getContentPane();

	c.setLayout(new BorderLayout());

	c.add(panel, BorderLayout.CENTER);

//	f.pack();

	f.setSize(300, 300);

	f.setVisible(true);

    }

}