/*

 * 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package javax.swing.plaf.basic;

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import javax.swing.border.*;

import javax.swing.plaf.*;

import javax.swing.text.View;

import sun.swing.SwingUtilities2;

import sun.awt.AppContext;

import java.util.Enumeration;

import java.util.HashSet;

/**

 * RadioButtonUI implementation for BasicRadioButtonUI

 *

 * @author Jeff Dinkins

 */

public class BasicRadioButtonUI extends BasicToggleButtonUI

{

    private static final Object BASIC_RADIO_BUTTON_UI_KEY = new Object();

    /**

     * The icon.

     */

    protected Icon icon;

    private boolean defaults_initialized = false;

    private final static String propertyPrefix = "RadioButton" + ".";

    private KeyListener keyListener = null;

    // ********************************

    //        Create PLAF

    // ********************************

    /**

     * Returns an instance of {@code BasicRadioButtonUI}.

     *

     * @param b a component

     * @return an instance of {@code BasicRadioButtonUI}

     */

    public static ComponentUI createUI(JComponent b) {

        AppContext appContext = AppContext.getAppContext();

        BasicRadioButtonUI radioButtonUI =

                (BasicRadioButtonUI) appContext.get(BASIC_RADIO_BUTTON_UI_KEY);

        if (radioButtonUI == null) {

            radioButtonUI = new BasicRadioButtonUI();

            appContext.put(BASIC_RADIO_BUTTON_UI_KEY, radioButtonUI);

        }

        return radioButtonUI;

    }

    @Override

    protected String getPropertyPrefix() {

        return propertyPrefix;

    }

    // ********************************

    //        Install PLAF

    // ********************************

    @Override

    protected void installDefaults(AbstractButton b) {

        super.installDefaults(b);

        if(!defaults_initialized) {

            icon = UIManager.getIcon(getPropertyPrefix() + "icon");

            defaults_initialized = true;

        }

    }

    // ********************************

    //        Uninstall PLAF

    // ********************************

    @Override

    protected void uninstallDefaults(AbstractButton b) {

        super.uninstallDefaults(b);

        defaults_initialized = false;

    }

    /**

     * Returns the default icon.

     *

     * @return the default icon

     */

    public Icon getDefaultIcon() {

        return icon;

    }

    // ********************************

    //        Install Listeners

    // ********************************

    @Override

    protected void installListeners(AbstractButton button) {

        super.installListeners(button);

        // Only for JRadioButton

        if (!(button instanceof JRadioButton))

            return;

        keyListener = createKeyListener();

        button.addKeyListener(keyListener);

        // Need to get traversal key event

        button.setFocusTraversalKeysEnabled(false);

        // Map actions to the arrow keys

        button.getActionMap().put("Previous", new SelectPreviousBtn());

        button.getActionMap().put("Next", new SelectNextBtn());

        button.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT).

            put(KeyStroke.getKeyStroke("UP"), "Previous");

        button.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT).

            put(KeyStroke.getKeyStroke("DOWN"), "Next");

        button.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT).

            put(KeyStroke.getKeyStroke("LEFT"), "Previous");

        button.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT).

            put(KeyStroke.getKeyStroke("RIGHT"), "Next");

    }

    // ********************************

    //        UnInstall Listeners

    // ********************************

    @Override

    protected void uninstallListeners(AbstractButton button) {

        super.uninstallListeners(button);

        // Only for JRadioButton

        if (!(button instanceof JRadioButton))

            return;

        // Unmap actions from the arrow keys

        button.getActionMap().remove("Previous");

        button.getActionMap().remove("Next");

        button.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT)

                    .remove(KeyStroke.getKeyStroke("UP"));

        button.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT)

                    .remove(KeyStroke.getKeyStroke("DOWN"));

        button.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT)

                    .remove(KeyStroke.getKeyStroke("LEFT"));

        button.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT)

                    .remove(KeyStroke.getKeyStroke("RIGHT"));

        if (keyListener != null) {

            button.removeKeyListener(keyListener);

            keyListener = null;

        }

    }

    /* These Dimensions/Rectangles are allocated once for all

     * RadioButtonUI.paint() calls.  Re-using rectangles

     * rather than allocating them in each paint call substantially

     * reduced the time it took paint to run.  Obviously, this

     * method can't be re-entered.

     */

    private static Dimension size = new Dimension();

    private static Rectangle viewRect = new Rectangle();

    private static Rectangle iconRect = new Rectangle();

    private static Rectangle textRect = new Rectangle();

    /**

     * paint the radio button

     */

    @Override

    public synchronized void paint(Graphics g, JComponent c) {

        AbstractButton b = (AbstractButton) c;

        ButtonModel model = b.getModel();

        Font f = c.getFont();

        g.setFont(f);

        FontMetrics fm = SwingUtilities2.getFontMetrics(c, g, f);

        Insets i = c.getInsets();

        size = b.getSize(size);

        viewRect.x = i.left;

        viewRect.y = i.top;

        viewRect.width = size.width - (i.right + viewRect.x);

        viewRect.height = size.height - (i.bottom + viewRect.y);

        iconRect.x = iconRect.y = iconRect.width = iconRect.height = 0;

        textRect.x = textRect.y = textRect.width = textRect.height = 0;

        Icon altIcon = b.getIcon();

        Icon selectedIcon = null;

        Icon disabledIcon = null;

        String text = SwingUtilities.layoutCompoundLabel(

            c, fm, b.getText(), altIcon != null ? altIcon : getDefaultIcon(),

            b.getVerticalAlignment(), b.getHorizontalAlignment(),

            b.getVerticalTextPosition(), b.getHorizontalTextPosition(),

            viewRect, iconRect, textRect,

            b.getText() == null ? 0 : b.getIconTextGap());

        // fill background

        if(c.isOpaque()) {

            g.setColor(b.getBackground());

            g.fillRect(0,0, size.width, size.height);

        }

        // Paint the radio button

        if(altIcon != null) {

            if(!model.isEnabled()) {

                if(model.isSelected()) {

                   altIcon = b.getDisabledSelectedIcon();

                } else {

                   altIcon = b.getDisabledIcon();

                }

            } else if(model.isPressed() && model.isArmed()) {

                altIcon = b.getPressedIcon();

                if(altIcon == null) {

                    // Use selected icon

                    altIcon = b.getSelectedIcon();

                }

            } else if(model.isSelected()) {

                if(b.isRolloverEnabled() && model.isRollover()) {

                        altIcon = b.getRolloverSelectedIcon();

                        if (altIcon == null) {

                                altIcon = b.getSelectedIcon();

                        }

                } else {

                        altIcon = b.getSelectedIcon();

                }

            } else if(b.isRolloverEnabled() && model.isRollover()) {

                altIcon = b.getRolloverIcon();

            }

            if(altIcon == null) {

                altIcon = b.getIcon();

            }

            altIcon.paintIcon(c, g, iconRect.x, iconRect.y);

        } else {

            getDefaultIcon().paintIcon(c, g, iconRect.x, iconRect.y);

        }

        // Draw the Text

        if(text != null) {

            View v = (View) c.getClientProperty(BasicHTML.propertyKey);

            if (v != null) {

                v.paint(g, textRect);

            } else {

                paintText(g, b, textRect, text);

            }

            if(b.hasFocus() && b.isFocusPainted() &&

               textRect.width > 0 && textRect.height > 0 ) {

                paintFocus(g, textRect, size);

            }

        }

    }

    /**

     * Paints focused radio button.

     *

     * @param g an instance of {@code Graphics}

     * @param textRect bounds

     * @param size the size of radio button

     */

    protected void paintFocus(Graphics g, Rectangle textRect, Dimension size) {

    }

    /* These Insets/Rectangles are allocated once for all

     * RadioButtonUI.getPreferredSize() calls.  Re-using rectangles

     * rather than allocating them in each call substantially

     * reduced the time it took getPreferredSize() to run.  Obviously,

     * this method can't be re-entered.

     */

    private static Rectangle prefViewRect = new Rectangle();

    private static Rectangle prefIconRect = new Rectangle();

    private static Rectangle prefTextRect = new Rectangle();

    private static Insets prefInsets = new Insets(0, 0, 0, 0);

    /**

     * The preferred size of the radio button

     */

    @Override

    public Dimension getPreferredSize(JComponent c) {

        if(c.getComponentCount() > 0) {

            return null;

        }

        AbstractButton b = (AbstractButton) c;

        String text = b.getText();

        Icon buttonIcon = b.getIcon();

        if(buttonIcon == null) {

            buttonIcon = getDefaultIcon();

        }

        Font font = b.getFont();

        FontMetrics fm = b.getFontMetrics(font);

        prefViewRect.x = prefViewRect.y = 0;

        prefViewRect.width = Short.MAX_VALUE;

        prefViewRect.height = Short.MAX_VALUE;

        prefIconRect.x = prefIconRect.y = prefIconRect.width = prefIconRect.height = 0;

        prefTextRect.x = prefTextRect.y = prefTextRect.width = prefTextRect.height = 0;

        SwingUtilities.layoutCompoundLabel(

            c, fm, text, buttonIcon,

            b.getVerticalAlignment(), b.getHorizontalAlignment(),

            b.getVerticalTextPosition(), b.getHorizontalTextPosition(),

            prefViewRect, prefIconRect, prefTextRect,

            text == null ? 0 : b.getIconTextGap());

        // find the union of the icon and text rects (from Rectangle.java)

        int x1 = Math.min(prefIconRect.x, prefTextRect.x);

        int x2 = Math.max(prefIconRect.x + prefIconRect.width,

                          prefTextRect.x + prefTextRect.width);

        int y1 = Math.min(prefIconRect.y, prefTextRect.y);

        int y2 = Math.max(prefIconRect.y + prefIconRect.height,

                          prefTextRect.y + prefTextRect.height);

        int width = x2 - x1;

        int height = y2 - y1;

        prefInsets = b.getInsets(prefInsets);

        width += prefInsets.left + prefInsets.right;

        height += prefInsets.top + prefInsets.bottom;

        return new Dimension(width, height);

    }

    /////////////////////////// Private functions ////////////////////////

    /**

     * Creates the key listener to handle tab navigation in JRadioButton Group.

     */

    private KeyListener createKeyListener() {

         if (keyListener == null) {

            keyListener = new KeyHandler();

        }

        return keyListener;

    }

    private boolean isValidRadioButtonObj(Object obj) {

        return ((obj instanceof JRadioButton) &&

                    ((JRadioButton) obj).isVisible() &&

                    ((JRadioButton) obj).isEnabled());

    }

    /**

     * Select radio button based on "Previous" or "Next" operation

     *

     * @param event, the event object.

     * @param next, indicate if it's next one

     */

    private void selectRadioButton(ActionEvent event, boolean next) {

        // Get the source of the event.

        Object eventSrc = event.getSource();

        // Check whether the source is JRadioButton, it so, whether it is visible

        if (!isValidRadioButtonObj(eventSrc))

            return;

        ButtonGroupInfo btnGroupInfo = new ButtonGroupInfo((JRadioButton)eventSrc);

        btnGroupInfo.selectNewButton(next);

    }

    /////////////////////////// Inner Classes ////////////////////////

    @SuppressWarnings("serial")

    private class SelectPreviousBtn extends AbstractAction {

        public SelectPreviousBtn() {

            super("Previous");

        }

        public void actionPerformed(ActionEvent e) {

           BasicRadioButtonUI.this.selectRadioButton(e, false);

        }

    }

    @SuppressWarnings("serial")

    private class SelectNextBtn extends AbstractAction{

        public SelectNextBtn() {

            super("Next");

        }

        public void actionPerformed(ActionEvent e) {

            BasicRadioButtonUI.this.selectRadioButton(e, true);

        }

    }

    /**

     * ButtonGroupInfo, used to get related info in button group

     * for given radio button

     */

    private class ButtonGroupInfo {

        JRadioButton activeBtn = null;

        JRadioButton firstBtn = null;

        JRadioButton lastBtn = null;

        JRadioButton previousBtn = null;

        JRadioButton nextBtn = null;

        HashSet<JRadioButton> btnsInGroup = null;

        boolean srcFound = false;

        public ButtonGroupInfo(JRadioButton btn) {

            activeBtn = btn;

            btnsInGroup = new HashSet<JRadioButton>();

        }

        // Check if given object is in the button group

        boolean containsInGroup(Object obj){

           return btnsInGroup.contains(obj);

        }

        // Check if the next object to gain focus belongs

        // to the button group or not

        Component getFocusTransferBaseComponent(boolean next){

            Component focusBaseComp = activeBtn;

            Window container = SwingUtilities.getWindowAncestor(activeBtn);

            if (container != null) {

                FocusTraversalPolicy policy = container.getFocusTraversalPolicy();

                Component comp = next ? policy.getComponentAfter(container, activeBtn)

                                      : policy.getComponentBefore(container, activeBtn);

                // If next component in the button group, use last/first button as base focus

                // otherwise, use the activeBtn as the base focus

                if (containsInGroup(comp)) {

                    focusBaseComp = next ? lastBtn : firstBtn;

                }

            }

            return focusBaseComp;

        }

        boolean getButtonGroupInfo() {

            if (activeBtn == null)

                return false;

            btnsInGroup.clear();

            // Get the button model from the source.

            ButtonModel model = activeBtn.getModel();

            if (!(model instanceof DefaultButtonModel))

                return false;

            // If the button model is DefaultButtonModel, and use it, otherwise return.

            DefaultButtonModel bm = (DefaultButtonModel) model;

            // get the ButtonGroup of the button from the button model

            ButtonGroup group = bm.getGroup();

            if (group == null)

                return false;

            // Get all the buttons in the group

            Enumeration<AbstractButton> e = group.getElements();

            if (e == null)

                return false;

            while (e.hasMoreElements()) {

                AbstractButton curElement = e.nextElement();

                if (!isValidRadioButtonObj(curElement))

                    continue;

                btnsInGroup.add((JRadioButton) curElement);

                // If firstBtn is not set yet, curElement is that first button

                if (null == firstBtn)

                    firstBtn = (JRadioButton) curElement;

                if (activeBtn == curElement)

                    srcFound = true;

                else if (!srcFound) {

                    // The source has not been yet found and the current element

                    // is the last previousBtn

                    previousBtn = (JRadioButton) curElement;

                } else if (nextBtn == null) {

                    // The source has been found and the current element

                    // is the next valid button of the list

                    nextBtn = (JRadioButton) curElement;

                }

                // Set new last "valid" JRadioButton of the list

                lastBtn = (JRadioButton) curElement;

            }