/*

 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package javax.swing.plaf.basic;

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import javax.swing.event.*;

import javax.swing.plaf.*;

import javax.swing.border.Border;

import java.beans.*;

import sun.swing.DefaultLookup;

/**

 * Divider used by BasicSplitPaneUI. Subclassers may wish to override

 * paint to do something more interesting.

 * The border effect is drawn in BasicSplitPaneUI, so if you don't like

 * that border, reset it there.

 * To conditionally drag from certain areas subclass mousePressed and

 * call super when you wish the dragging to begin.

 * <p>

 * <strong>Warning:</strong>

 * Serialized objects of this class will not be compatible with

 * future Swing releases. The current serialization support is

 * appropriate for short term storage or RMI between applications running

 * the same version of Swing.  As of 1.4, support for long term storage

 * of all JavaBeans™

 * has been added to the <code>java.beans</code> package.

 * Please see {@link java.beans.XMLEncoder}.

 *

 * @author Scott Violet

 */

@SuppressWarnings("serial") // Same-version serialization only

public class BasicSplitPaneDivider extends Container

    implements PropertyChangeListener

{

    /**

     * Width or height of the divider based on orientation

     * {@code BasicSplitPaneUI} adds two to this.

     */

    protected static final int ONE_TOUCH_SIZE = 6;

    /**

     * The offset of the divider.

     */

    protected static final int ONE_TOUCH_OFFSET = 2;

    /**

     * Handles mouse dragging message to do the actual dragging.

     */

    protected DragController dragger;

    /**

     * UI this instance was created from.

     */

    protected BasicSplitPaneUI splitPaneUI;

    /**

     * Size of the divider.

     */

    protected int dividerSize = 0; // default - SET TO 0???

    /**

     * Divider that is used for noncontinuous layout mode.

     */

    protected Component hiddenDivider;

    /**

     * JSplitPane the receiver is contained in.

     */

    protected JSplitPane splitPane;

    /**

     * Handles mouse events from both this class, and the split pane.

     * Mouse events are handled for the splitpane since you want to be able

     * to drag when clicking on the border of the divider, which is not

     * drawn by the divider.

     */

    protected MouseHandler mouseHandler;

    /**

     * Orientation of the JSplitPane.

     */

    protected int orientation;

    /**

     * Button for quickly toggling the left component.

     */

    protected JButton leftButton;

    /**

     * Button for quickly toggling the right component.

     */

    protected JButton rightButton;

    /** Border. */

    private Border border;

    /**

     * Is the mouse over the divider?

     */

    private boolean mouseOver;

    private int oneTouchSize;

    private int oneTouchOffset;

    /**

     * If true the one touch buttons are centered on the divider.

     */

    private boolean centerOneTouchButtons;

    /**

     * Creates an instance of {@code BasicSplitPaneDivider}. Registers this

     * instance for mouse events and mouse dragged events.

     *

     * @param ui an instance of {@code BasicSplitPaneUI}

     */

    public BasicSplitPaneDivider(BasicSplitPaneUI ui) {

        oneTouchSize = DefaultLookup.getInt(ui.getSplitPane(), ui,

                "SplitPane.oneTouchButtonSize", ONE_TOUCH_SIZE);

        oneTouchOffset = DefaultLookup.getInt(ui.getSplitPane(), ui,

                "SplitPane.oneTouchButtonOffset", ONE_TOUCH_OFFSET);

        centerOneTouchButtons = DefaultLookup.getBoolean(ui.getSplitPane(),

                 ui, "SplitPane.centerOneTouchButtons", true);

        setLayout(new DividerLayout());

        setBasicSplitPaneUI(ui);

        orientation = splitPane.getOrientation();

        setCursor((orientation == JSplitPane.HORIZONTAL_SPLIT) ?

                  Cursor.getPredefinedCursor(Cursor.E_RESIZE_CURSOR) :

                  Cursor.getPredefinedCursor(Cursor.S_RESIZE_CURSOR));

        setBackground(UIManager.getColor("SplitPane.background"));

    }

    private void revalidateSplitPane() {

        invalidate();

        if (splitPane != null) {

            splitPane.revalidate();

        }

    }

    /**

     * Sets the {@code SplitPaneUI} that is using the receiver.

     *

     * @param newUI the new {@code SplitPaneUI}

     */

    public void setBasicSplitPaneUI(BasicSplitPaneUI newUI) {

        if (splitPane != null) {

            splitPane.removePropertyChangeListener(this);

           if (mouseHandler != null) {

               splitPane.removeMouseListener(mouseHandler);

               splitPane.removeMouseMotionListener(mouseHandler);

               removeMouseListener(mouseHandler);

               removeMouseMotionListener(mouseHandler);

               mouseHandler = null;

           }

        }

        splitPaneUI = newUI;

        if (newUI != null) {

            splitPane = newUI.getSplitPane();

            if (splitPane != null) {

                if (mouseHandler == null) mouseHandler = new MouseHandler();

                splitPane.addMouseListener(mouseHandler);

                splitPane.addMouseMotionListener(mouseHandler);

                addMouseListener(mouseHandler);

                addMouseMotionListener(mouseHandler);

                splitPane.addPropertyChangeListener(this);

                if (splitPane.isOneTouchExpandable()) {

                    oneTouchExpandableChanged();

                }

            }

        }

        else {

            splitPane = null;

        }

    }

    /**

     * Returns the {@code SplitPaneUI} the receiver is currently in.

     *

     * @return the {@code SplitPaneUI} the receiver is currently in

     */

    public BasicSplitPaneUI getBasicSplitPaneUI() {

        return splitPaneUI;

    }

    /**

     * Sets the size of the divider to {@code newSize}. That is

     * the width if the splitpane is {@code HORIZONTAL_SPLIT}, or

     * the height of {@code VERTICAL_SPLIT}.

     *

     * @param newSize a new size

     */

    public void setDividerSize(int newSize) {

        dividerSize = newSize;

    }

    /**

     * Returns the size of the divider, that is the width if the splitpane

     * is HORIZONTAL_SPLIT, or the height of VERTICAL_SPLIT.

     *

     * @return the size of the divider

     */

    public int getDividerSize() {

        return dividerSize;

    }

    /**

     * Sets the border of this component.

     *

     * @param border a new border

     * @since 1.3

     */

    public void setBorder(Border border) {

        Border         oldBorder = this.border;

        this.border = border;

    }

    /**

     * Returns the border of this component or null if no border is

     * currently set.

     *

     * @return the border object for this component

     * @see #setBorder

     * @since 1.3

     */

    public Border getBorder() {

        return border;

    }

    /**

     * If a border has been set on this component, returns the

     * border's insets, else calls super.getInsets.

     *

     * @return the value of the insets property.

     * @see #setBorder

     */

    public Insets getInsets() {

        Border    border = getBorder();

        if (border != null) {

            return border.getBorderInsets(this);

        }

        return super.getInsets();

    }

    /**

     * Sets whether or not the mouse is currently over the divider.

     *

     * @param mouseOver whether or not the mouse is currently over the divider

     * @since 1.5

     */

    protected void setMouseOver(boolean mouseOver) {

        this.mouseOver = mouseOver;

    }

    /**

     * Returns whether or not the mouse is currently over the divider

     *

     * @return whether or not the mouse is currently over the divider

     * @since 1.5

     */

    public boolean isMouseOver() {

        return mouseOver;

    }

    /**

     * Returns dividerSize x dividerSize

     */

    public Dimension getPreferredSize() {

        // Ideally this would return the size from the layout manager,

        // but that could result in the layed out size being different from

        // the dividerSize, which may break developers as well as

        // BasicSplitPaneUI.

        if (orientation == JSplitPane.HORIZONTAL_SPLIT) {

            return new Dimension(getDividerSize(), 1);

        }

        return new Dimension(1, getDividerSize());

    }

    /**

     * Returns dividerSize x dividerSize

     */

    public Dimension getMinimumSize() {

        return getPreferredSize();

    }

    /**

     * Property change event, presumably from the JSplitPane, will message

     * updateOrientation if necessary.

     */

    public void propertyChange(PropertyChangeEvent e) {

        if (e.getSource() == splitPane) {

            if (e.getPropertyName() == JSplitPane.ORIENTATION_PROPERTY) {

                orientation = splitPane.getOrientation();

                setCursor((orientation == JSplitPane.HORIZONTAL_SPLIT) ?

                          Cursor.getPredefinedCursor(Cursor.E_RESIZE_CURSOR) :

                          Cursor.getPredefinedCursor(Cursor.S_RESIZE_CURSOR));

                revalidateSplitPane();

            }

            else if (e.getPropertyName() == JSplitPane.

                      ONE_TOUCH_EXPANDABLE_PROPERTY) {

                oneTouchExpandableChanged();

            }

        }

    }

    /**

     * Paints the divider.

     */

    public void paint(Graphics g) {

      super.paint(g);

      // Paint the border.

      Border   border = getBorder();

      if (border != null) {

          Dimension     size = getSize();

          border.paintBorder(this, g, 0, 0, size.width, size.height);

      }

    }

    /**

     * Messaged when the oneTouchExpandable value of the JSplitPane the

     * receiver is contained in changes. Will create the

     * <code>leftButton</code> and <code>rightButton</code> if they

     * are null. invalidates the receiver as well.

     */

    protected void oneTouchExpandableChanged() {

        if (!DefaultLookup.getBoolean(splitPane, splitPaneUI,

                           "SplitPane.supportsOneTouchButtons", true)) {

            // Look and feel doesn't want to support one touch buttons, bail.

            return;

        }

        if (splitPane.isOneTouchExpandable() &&

            leftButton == null &&

            rightButton == null) {

            /* Create the left button and add an action listener to

               expand/collapse it. */

            leftButton = createLeftOneTouchButton();

            if (leftButton != null)

                leftButton.addActionListener(new OneTouchActionHandler(true));

            /* Create the right button and add an action listener to

               expand/collapse it. */

            rightButton = createRightOneTouchButton();

            if (rightButton != null)

                rightButton.addActionListener(new OneTouchActionHandler

                    (false));

            if (leftButton != null && rightButton != null) {

                add(leftButton);

                add(rightButton);

            }

        }

        revalidateSplitPane();

    }

    /**

     * Creates and return an instance of {@code JButton} that can be used to

     * collapse the left component in the split pane.

     *

     * @return an instance of {@code JButton}

     */

    protected JButton createLeftOneTouchButton() {

        JButton b = new JButton() {

            public void setBorder(Border b) {

            }

            public void paint(Graphics g) {

                if (splitPane != null) {

                    int[]   xs = new int[3];

                    int[]   ys = new int[3];

                    int     blockSize;

                    // Fill the background first ...

                    g.setColor(this.getBackground());

                    g.fillRect(0, 0, this.getWidth(),

                               this.getHeight());

                    // ... then draw the arrow.

                    g.setColor(Color.black);

                    if (orientation == JSplitPane.VERTICAL_SPLIT) {

                        blockSize = Math.min(getHeight(), oneTouchSize);

                        xs[0] = blockSize;

                        xs[1] = 0;

                        xs[2] = blockSize << 1;

                        ys[0] = 0;

                        ys[1] = ys[2] = blockSize;

                        g.drawPolygon(xs, ys, 3); // Little trick to make the

                                                  // arrows of equal size

                    }

                    else {

                        blockSize = Math.min(getWidth(), oneTouchSize);

                        xs[0] = xs[2] = blockSize;

                        xs[1] = 0;

                        ys[0] = 0;

                        ys[1] = blockSize;

                        ys[2] = blockSize << 1;

                    }

                    g.fillPolygon(xs, ys, 3);

                }

            }

            // Don't want the button to participate in focus traversable.

            public boolean isFocusTraversable() {

                return false;

            }

        };

        b.setMinimumSize(new Dimension(oneTouchSize, oneTouchSize));

        b.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));

        b.setFocusPainted(false);

        b.setBorderPainted(false);

        b.setRequestFocusEnabled(false);

        return b;

    }

    /**

     * Creates and return an instance of {@code JButton} that can be used to

     * collapse the right component in the split pane.

     *

     * @return an instance of {@code JButton}

     */

    protected JButton createRightOneTouchButton() {

        JButton b = new JButton() {

            public void setBorder(Border border) {

            }

            public void paint(Graphics g) {

                if (splitPane != null) {

                    int[]          xs = new int[3];

                    int[]          ys = new int[3];

                    int            blockSize;

                    // Fill the background first ...

                    g.setColor(this.getBackground());

                    g.fillRect(0, 0, this.getWidth(),

                               this.getHeight());

                    // ... then draw the arrow.

                    if (orientation == JSplitPane.VERTICAL_SPLIT) {

                        blockSize = Math.min(getHeight(), oneTouchSize);

                        xs[0] = blockSize;

                        xs[1] = blockSize << 1;

                        xs[2] = 0;

                        ys[0] = blockSize;

                        ys[1] = ys[2] = 0;

                    }

                    else {

                        blockSize = Math.min(getWidth(), oneTouchSize);

                        xs[0] = xs[2] = 0;

                        xs[1] = blockSize;

                        ys[0] = 0;

                        ys[1] = blockSize;

                        ys[2] = blockSize << 1;

                    }

                    g.setColor(Color.black);

                    g.fillPolygon(xs, ys, 3);

                }

            }

            // Don't want the button to participate in focus traversable.

            public boolean isFocusTraversable() {

                return false;

            }

        };

        b.setMinimumSize(new Dimension(oneTouchSize, oneTouchSize));

        b.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));

        b.setFocusPainted(false);

        b.setBorderPainted(false);

        b.setRequestFocusEnabled(false);

        return b;

    }

    /**

     * Message to prepare for dragging. This messages the BasicSplitPaneUI

     * with startDragging.

     */

    protected void prepareForDragging() {

        splitPaneUI.startDragging();

    }

    /**

     * Messages the BasicSplitPaneUI with dragDividerTo that this instance