/*
 * @(#)MetalToolBarUI.java	1.39 03/12/19
 *
 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package javax.swing.plaf.metal;

import javax.swing.*;
import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.GraphicsEnvironment;
import java.awt.Insets;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.event.*;
import java.lang.ref.WeakReference;
import java.util.*;

import java.beans.PropertyChangeListener;

import javax.swing.event.*;
import javax.swing.border.*;
import javax.swing.plaf.*;
import javax.swing.plaf.basic.*;

/**
 * A Metal Look and Feel implementation of ToolBarUI.  This implementation 
 * is a "combined" view/controller.
 * <p>
 *
 * @version 1.39 12/19/03
 * @author Jeff Shapiro
 */
public class MetalToolBarUI extends BasicToolBarUI
{
    /**
     * An array of WeakReferences that point to JComponents. This will contain
     * instances of JToolBars and JMenuBars and is used to find
     * JToolBars/JMenuBars that border each other.
     */
    private static java.util.List components = new ArrayList();

    /**
     * This protected field is implemenation specific. Do not access directly
     * or override. Use the create method instead.
     *
     * @see #createContainerListener
     */
    protected ContainerListener contListener;

    /**
     * This protected field is implemenation specific. Do not access directly
     * or override. Use the create method instead.
     *
     * @see #createRolloverListener
     */
    protected PropertyChangeListener rolloverListener;

    private static Border nonRolloverBorder;


    /**
     * Registers the specified component.
     */
    synchronized static void register(JComponent c) {
        if (c == null) {
            // Exception is thrown as convenience for callers that are
            // typed to throw an NPE.
            throw new NullPointerException("JComponent must be non-null");
        }
        components.add(new WeakReference(c));
    }

    /**
     * Unregisters the specified component.
     */
    synchronized static void unregister(JComponent c) {
        for (int counter = components.size() - 1; counter >= 0; counter--) {
            // Search for the component, removing any flushed references
            // along the way.
            WeakReference ref = (WeakReference)components.get(counter);
            Object target = ((WeakReference)components.get(counter)).get();

            if (target == c || target == null) {
                components.remove(counter);
            }
        }
    }

    /**
     * Finds a previously registered component of class <code>target</code>
     * that shares the JRootPane ancestor of <code>from</code>.
     */
    synchronized static Object findRegisteredComponentOfType(JComponent from,
                                                             Class target) {
        JRootPane rp = SwingUtilities.getRootPane(from);
        if (rp != null) {
            for (int counter = components.size() - 1; counter >= 0; counter--){
                Object component = ((WeakReference)components.get(counter)).
                                   get();

                if (component == null) {
                    // WeakReference has gone away, remove the WeakReference
                    components.remove(counter);
                }
                else if (target.isInstance(component) && SwingUtilities.
                         getRootPane((Component)component) == rp) {
                    return component;
                }
            }
        }
        return null;
    }

    /**
     * Returns true if the passed in JMenuBar is above a horizontal
     * JToolBar.
     */
    static boolean doesMenuBarBorderToolBar(JMenuBar c) {
        JToolBar tb = (JToolBar)MetalToolBarUI.
                    findRegisteredComponentOfType(c, JToolBar.class);
        if (tb != null && tb.getOrientation() == JToolBar.HORIZONTAL) {
            JRootPane rp = SwingUtilities.getRootPane(c);
            Point point = new Point(0, 0);
            point = SwingUtilities.convertPoint(c, point, rp);
            int menuX = point.x;
            int menuY = point.y;
            point.x = point.y = 0;
            point = SwingUtilities.convertPoint(tb, point, rp);
            return (point.x == menuX && menuY + c.getHeight() == point.y &&
                    c.getWidth() == tb.getWidth());
        }
        return false;
    }

    public static ComponentUI createUI( JComponent c )
    {
	return new MetalToolBarUI();
    }

    public void installUI( JComponent c )
    {
        super.installUI( c );
        register(c);
    }

    public void uninstallUI( JComponent c )
    {
        super.uninstallUI( c );
	nonRolloverBorder = null;
        unregister(c);
    }

    protected void installListeners() {
        super.installListeners();

	contListener = createContainerListener();
	if (contListener != null) {
	    toolBar.addContainerListener(contListener);
	}
	rolloverListener = createRolloverListener();
	if (rolloverListener != null) {
	    toolBar.addPropertyChangeListener(rolloverListener);
	}
    }

    protected void uninstallListeners() {
        super.uninstallListeners();

	if (contListener != null) {
	    toolBar.removeContainerListener(contListener);
	}
	rolloverListener = createRolloverListener();
	if (rolloverListener != null) {
	    toolBar.removePropertyChangeListener(rolloverListener);
	}
    }

    protected Border createRolloverBorder() {
	return super.createRolloverBorder();
    }

    protected Border createNonRolloverBorder() {
        return super.createNonRolloverBorder();
    }


    /**
     * Creates a non rollover border for Toggle buttons in the toolbar.
     */
    private Border createNonRolloverToggleBorder() {
	return createNonRolloverBorder();
    }
    
    protected void setBorderToNonRollover(Component c) {
	if (c instanceof JToggleButton && !(c instanceof JCheckBox)) {
	    // 4735514, 4886944: The method createNonRolloverToggleBorder() is
	    // private in BasicToolBarUI so we can't override it. We still need
	    // to call super from this method so that it can save away the
	    // original border and then we install ours.

	    // Before calling super we get a handle to the old border, because
	    // super will install a non-UIResource border that we can't
	    // distinguish from one provided by an application.
	    JToggleButton b = (JToggleButton)c;
	    Border border = b.getBorder();
	    super.setBorderToNonRollover(c);
	    if (border instanceof UIResource) {
		if (nonRolloverBorder == null) {
		    nonRolloverBorder = createNonRolloverToggleBorder();
		}
		b.setBorder(nonRolloverBorder);
	    }
	} else {
	    super.setBorderToNonRollover(c);
	}
    }


    /**
     * Creates a container listener that will be added to the JToolBar.
     * If this method returns null then it will not be added to the 
     * toolbar.
     *
     * @return an instance of a <code>ContainerListener</code> or null
     */
    protected ContainerListener createContainerListener() {
	return null;
    }

    /**
     * Creates a property change listener that will be added to the JToolBar.
     * If this method returns null then it will not be added to the 
     * toolbar.
     *
     * @return an instance of a <code>PropertyChangeListener</code> or null
     */
    protected PropertyChangeListener createRolloverListener() {
	return null;
    }

    protected MouseInputListener createDockingListener( )
    {
	return new MetalDockingListener( toolBar );
    }

    protected void setDragOffset(Point p) {
	if (!GraphicsEnvironment.isHeadless()) {
	    if (dragWindow == null) {
		dragWindow = createDragWindow(toolBar);
	    }
	    dragWindow.setOffset(p);
	}
    }

    /**
     * If necessary paints the background of the component, then invokes
     * <code>paint</code>.
     *
     * @param g Graphics to paint to
     * @param c JComponent painting on
     * @throws NullPointerException if <code>g</code> or <code>c</code> is
     *         null
     * @see javax.swing.plaf.ComponentUI#update
     * @see javax.swing.plaf.ComponentUI#paint
     * @since 1.5
     */
    public void update(Graphics g, JComponent c) {
        if (c.isOpaque() && (c.getBackground() instanceof UIResource) &&
                            ((JToolBar)c).getOrientation() ==
                      JToolBar.HORIZONTAL && UIManager.get(
                     "MenuBar.gradient") != null) {
            JRootPane rp = SwingUtilities.getRootPane(c);
            JMenuBar mb = (JMenuBar)findRegisteredComponentOfType(
                                    c, JMenuBar.class);
            if (mb != null && mb.isOpaque() &&
                              (mb.getBackground() instanceof UIResource)) {
                Point point = new Point(0, 0);
                point = SwingUtilities.convertPoint(c, point, rp);
                int x = point.x;
                int y = point.y;
                point.x = point.y = 0;
                point = SwingUtilities.convertPoint(mb, point, rp);
                if (point.x == x && y == point.y + mb.getHeight() &&
                     mb.getWidth() == c.getWidth() &&
                     MetalUtils.drawGradient(c, g, "MenuBar.gradient",
                     0, -mb.getHeight(), c.getWidth(), c.getHeight() +
                     mb.getHeight(), true)) {
                    paint(g, c);
                    return;
                }
            }
            if (MetalUtils.drawGradient(c, g, "MenuBar.gradient",
                           0, 0, c.getWidth(), c.getHeight(), true)) {
                paint(g, c);
                return;
            }
        }
        super.update(g, c);
    }

    // No longer used. Cannot remove for compatibility reasons
    protected class MetalContainerListener
	extends BasicToolBarUI.ToolBarContListener {}

    // No longer used. Cannot remove for compatibility reasons
    protected class MetalRolloverListener 
	extends BasicToolBarUI.PropertyListener {}

    protected class MetalDockingListener extends DockingListener {
        private boolean pressedInBumps = false;

	public MetalDockingListener(JToolBar t) {
	    super(t);
	} 

	public void mousePressed(MouseEvent e) { 
	    super.mousePressed(e);
            if (!toolBar.isEnabled()) {
                return;
            }
	    pressedInBumps = false;
	    Rectangle bumpRect = new Rectangle();

	    if (toolBar.getOrientation() == JToolBar.HORIZONTAL) {
		int x = MetalUtils.isLeftToRight(toolBar) ? 0 : toolBar.getSize().width-14;
		bumpRect.setBounds(x, 0, 14, toolBar.getSize().height);
	    } else {  // vertical
		bumpRect.setBounds(0, 0, toolBar.getSize().width, 14);
	    }
	    if (bumpRect.contains(e.getPoint())) {
	        pressedInBumps = true;
                Point dragOffset = e.getPoint();
                if (!MetalUtils.isLeftToRight(toolBar)) {
                    dragOffset.x -= (toolBar.getSize().width 
				     - toolBar.getPreferredSize().width);
                }
                setDragOffset(dragOffset);
	    }
	}

	public void mouseDragged(MouseEvent e) {
	    if (pressedInBumps) {
	        super.mouseDragged(e);
	    }
	}
    } // end class MetalDockingListener
}