/*

 * 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;

import java.applet.Applet;

import java.awt.*;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import static javax.swing.ClientPropertyKey.PopupFactory_FORCE_HEAVYWEIGHT_POPUP;

/**

 * <code>PopupFactory</code>, as the name implies, is used to obtain

 * instances of <code>Popup</code>s. <code>Popup</code>s are used to

 * display a <code>Component</code> above all other <code>Component</code>s

 * in a particular containment hierarchy. The general contract is that

 * once you have obtained a <code>Popup</code> from a

 * <code>PopupFactory</code>, you must invoke <code>hide</code> on the

 * <code>Popup</code>. The typical usage is:

 * <pre>

 *   PopupFactory factory = PopupFactory.getSharedInstance();

 *   Popup popup = factory.getPopup(owner, contents, x, y);

 *   popup.show();

 *   ...

 *   popup.hide();

 * </pre>

 *

 * @see Popup

 *

 * @since 1.4

 */

public class PopupFactory {

    /**

     * The shared instanceof <code>PopupFactory</code> is per

     * <code>AppContext</code>. This is the key used in the

     * <code>AppContext</code> to locate the <code>PopupFactory</code>.

     */

    private static final Object SharedInstanceKey =

        new StringBuffer("PopupFactory.SharedInstanceKey");

    /**

     * Max number of items to store in any one particular cache.

     */

    private static final int MAX_CACHE_SIZE = 5;

    /**

     * Key used to indicate a light weight popup should be used.

     */

    static final int LIGHT_WEIGHT_POPUP   = 0;

    /**

     * Key used to indicate a medium weight Popup should be used.

     */

    static final int MEDIUM_WEIGHT_POPUP  = 1;

    /*

     * Key used to indicate a heavy weight Popup should be used.

     */

    static final int HEAVY_WEIGHT_POPUP   = 2;

    /**

     * Default type of Popup to create.

     */

    private int popupType = LIGHT_WEIGHT_POPUP;

    /**

     * Sets the <code>PopupFactory</code> that will be used to obtain

     * <code>Popup</code>s.

     * This will throw an <code>IllegalArgumentException</code> if

     * <code>factory</code> is null.

     *

     * @param factory Shared PopupFactory

     * @exception IllegalArgumentException if <code>factory</code> is null

     * @see #getPopup

     */

    public static void setSharedInstance(PopupFactory factory) {

        if (factory == null) {

            throw new IllegalArgumentException("PopupFactory can not be null");

        }

        SwingUtilities.appContextPut(SharedInstanceKey, factory);

    }

    /**

     * Returns the shared <code>PopupFactory</code> which can be used

     * to obtain <code>Popup</code>s.

     *

     * @return Shared PopupFactory

     */

    public static PopupFactory getSharedInstance() {

        PopupFactory factory = (PopupFactory)SwingUtilities.appContextGet(

                         SharedInstanceKey);

        if (factory == null) {

            factory = new PopupFactory();

            setSharedInstance(factory);

        }

        return factory;

    }

    /**

     * Provides a hint as to the type of <code>Popup</code> that should

     * be created.

     */

    void setPopupType(int type) {

        popupType = type;

    }

    /**

     * Returns the preferred type of Popup to create.

     */

    int getPopupType() {

        return popupType;

    }

    /**

     * Creates a <code>Popup</code> for the Component <code>owner</code>

     * containing the Component <code>contents</code>. <code>owner</code>

     * is used to determine which <code>Window</code> the new

     * <code>Popup</code> will parent the <code>Component</code> the

     * <code>Popup</code> creates to. A null <code>owner</code> implies there

     * is no valid parent. <code>x</code> and

     * <code>y</code> specify the preferred initial location to place

     * the <code>Popup</code> at. Based on screen size, or other paramaters,

     * the <code>Popup</code> may not display at <code>x</code> and

     * <code>y</code>.

     *

     * @param owner    Component mouse coordinates are relative to, may be null

     * @param contents Contents of the Popup

     * @param x        Initial x screen coordinate

     * @param y        Initial y screen coordinate

     * @exception IllegalArgumentException if contents is null

     * @return Popup containing Contents

     */

    public Popup getPopup(Component owner, Component contents,

                          int x, int y) throws IllegalArgumentException {

        if (contents == null) {

            throw new IllegalArgumentException(

                          "Popup.getPopup must be passed non-null contents");

        }

        int popupType = getPopupType(owner, contents, x, y);

        Popup popup = getPopup(owner, contents, x, y, popupType);

        if (popup == null) {

            // Didn't fit, force to heavy.

            popup = getPopup(owner, contents, x, y, HEAVY_WEIGHT_POPUP);

        }

        return popup;

    }

    /**

     * Returns the popup type to use for the specified parameters.

     */

    private int getPopupType(Component owner, Component contents,

                             int ownerX, int ownerY) {

        int popupType = getPopupType();

        if (owner == null || invokerInHeavyWeightPopup(owner)) {

            popupType = HEAVY_WEIGHT_POPUP;

        }

        else if (popupType == LIGHT_WEIGHT_POPUP &&

                 !(contents instanceof JToolTip) &&

                 !(contents instanceof JPopupMenu)) {

            popupType = MEDIUM_WEIGHT_POPUP;

        }

        // Check if the parent component is an option pane.  If so we need to

        // force a heavy weight popup in order to have event dispatching work

        // correctly.

        Component c = owner;

        while (c != null) {

            if (c instanceof JComponent) {

                if (((JComponent)c).getClientProperty(

                            PopupFactory_FORCE_HEAVYWEIGHT_POPUP) == Boolean.TRUE) {

                    popupType = HEAVY_WEIGHT_POPUP;

                    break;

                }

            }

            c = c.getParent();

        }

        return popupType;

    }

    /**

     * Obtains the appropriate <code>Popup</code> based on

     * <code>popupType</code>.

     */

    private Popup getPopup(Component owner, Component contents,

                           int ownerX, int ownerY, int popupType) {

        if (GraphicsEnvironment.isHeadless()) {

            return getHeadlessPopup(owner, contents, ownerX, ownerY);

        }

        switch(popupType) {

        case LIGHT_WEIGHT_POPUP:

            return getLightWeightPopup(owner, contents, ownerX, ownerY);

        case MEDIUM_WEIGHT_POPUP:

            return getMediumWeightPopup(owner, contents, ownerX, ownerY);

        case HEAVY_WEIGHT_POPUP:

            return getHeavyWeightPopup(owner, contents, ownerX, ownerY);

        }

        return null;

    }

    /**

     * Creates a headless popup

     */

    private Popup getHeadlessPopup(Component owner, Component contents,

                                   int ownerX, int ownerY) {

        return HeadlessPopup.getHeadlessPopup(owner, contents, ownerX, ownerY);

    }

    /**

     * Creates a light weight popup.

     */

    private Popup getLightWeightPopup(Component owner, Component contents,

                                         int ownerX, int ownerY) {

        return LightWeightPopup.getLightWeightPopup(owner, contents, ownerX,

                                                    ownerY);

    }

    /**

     * Creates a medium weight popup.

     */

    private Popup getMediumWeightPopup(Component owner, Component contents,

                                          int ownerX, int ownerY) {

        return MediumWeightPopup.getMediumWeightPopup(owner, contents,

                                                      ownerX, ownerY);

    }

    /**

     * Creates a heavy weight popup.

     */

    private Popup getHeavyWeightPopup(Component owner, Component contents,

                                         int ownerX, int ownerY) {

        if (GraphicsEnvironment.isHeadless()) {

            return getMediumWeightPopup(owner, contents, ownerX, ownerY);

        }

        return HeavyWeightPopup.getHeavyWeightPopup(owner, contents, ownerX,

                                                    ownerY);

    }

    /**

     * Returns true if the Component <code>i</code> inside a heavy weight

     * <code>Popup</code>.

     */

    private boolean invokerInHeavyWeightPopup(Component i) {

        if (i != null) {

            Container parent;

            for(parent = i.getParent() ; parent != null ; parent =

                    parent.getParent()) {

                if (parent instanceof Popup.HeavyWeightWindow) {

                    return true;

                }

            }

        }

        return false;

    }

    /**

     * Popup implementation that uses a Window as the popup.

     */

    private static class HeavyWeightPopup extends Popup {

        private static final Object heavyWeightPopupCacheKey =

                 new StringBuffer("PopupFactory.heavyWeightPopupCache");

        /**

         * Returns either a new or recycled <code>Popup</code> containing

         * the specified children.

         */

        static Popup getHeavyWeightPopup(Component owner, Component contents,

                                         int ownerX, int ownerY) {

            Window window = (owner != null) ? SwingUtilities.

                              getWindowAncestor(owner) : null;

            HeavyWeightPopup popup = null;

            if (window != null) {

                popup = getRecycledHeavyWeightPopup(window);

            }

            boolean focusPopup = false;

            if(contents != null && contents.isFocusable()) {

                if(contents instanceof JPopupMenu) {

                    JPopupMenu jpm = (JPopupMenu) contents;

                    Component popComps[] = jpm.getComponents();

                    for (Component popComp : popComps) {

                        if (!(popComp instanceof MenuElement) &&

                                !(popComp instanceof JSeparator)) {

                            focusPopup = true;

                            break;

                        }

                    }

                }

            }

            if (popup == null ||

                ((JWindow) popup.getComponent())

                 .getFocusableWindowState() != focusPopup) {

                if(popup != null) {

                    // The recycled popup can't serve us well

                    // dispose it and create new one

                    popup._dispose();

                }

                popup = new HeavyWeightPopup();

            }

            popup.reset(owner, contents, ownerX, ownerY);

            if(focusPopup) {

                JWindow wnd = (JWindow) popup.getComponent();

                wnd.setFocusableWindowState(true);

                // Set window name. We need this in BasicPopupMenuUI

                // to identify focusable popup window.

                wnd.setName("###focusableSwingPopup###");

            }

            return popup;

        }

        /**

         * Returns a previously disposed heavy weight <code>Popup</code>

         * associated with <code>window</code>. This will return null if

         * there is no <code>HeavyWeightPopup</code> associated with

         * <code>window</code>.

         */

        private static HeavyWeightPopup getRecycledHeavyWeightPopup(Window w) {

            synchronized (HeavyWeightPopup.class) {

                List<HeavyWeightPopup> cache;

                Map<Window, List<HeavyWeightPopup>> heavyPopupCache = getHeavyWeightPopupCache();

                if (heavyPopupCache.containsKey(w)) {

                    cache = heavyPopupCache.get(w);

                } else {

                    return null;

                }

                if (cache.size() > 0) {

                    HeavyWeightPopup r = cache.get(0);

                    cache.remove(0);

                    return r;

                }

                return null;

            }

        }

        /**

         * Returns the cache to use for heavy weight popups. Maps from

         * <code>Window</code> to a <code>List</code> of

         * <code>HeavyWeightPopup</code>s.

         */

        private static Map<Window, List<HeavyWeightPopup>> getHeavyWeightPopupCache() {

            synchronized (HeavyWeightPopup.class) {

                Map<Window, List<HeavyWeightPopup>> cache = (Map<Window, List<HeavyWeightPopup>>)SwingUtilities.appContextGet(

                                  heavyWeightPopupCacheKey);

                if (cache == null) {

                    cache = new HashMap<Window, List<HeavyWeightPopup>>(2);

                    SwingUtilities.appContextPut(heavyWeightPopupCacheKey,

                                                 cache);

                }

                return cache;

            }

        }

        /**

         * Recycles the passed in <code>HeavyWeightPopup</code>.

         */

        private static void recycleHeavyWeightPopup(HeavyWeightPopup popup) {

            synchronized (HeavyWeightPopup.class) {

                List<HeavyWeightPopup> cache;

                Window window = SwingUtilities.getWindowAncestor(

                                     popup.getComponent());

                Map<Window, List<HeavyWeightPopup>> heavyPopupCache = getHeavyWeightPopupCache();

                if (window instanceof Popup.DefaultFrame ||

                                      !window.isVisible()) {

                    // If the Window isn't visible, we don't cache it as we

                    // likely won't ever get a windowClosed event to clean up.

                    // We also don't cache DefaultFrames as this indicates

                    // there wasn't a valid Window parent, and thus we don't

                    // know when to clean up.

                    popup._dispose();

                    return;

                } else if (heavyPopupCache.containsKey(window)) {

                    cache = heavyPopupCache.get(window);

                } else {

                    cache = new ArrayList<HeavyWeightPopup>();

                    heavyPopupCache.put(window, cache);

                    // Clean up if the Window is closed

                    final Window w = window;

                    w.addWindowListener(new WindowAdapter() {

                        public void windowClosed(WindowEvent e) {

                            List<HeavyWeightPopup> popups;

                            synchronized(HeavyWeightPopup.class) {

                                Map<Window, List<HeavyWeightPopup>> heavyPopupCache2 =

                                              getHeavyWeightPopupCache();

                                popups = heavyPopupCache2.remove(w);

                            }

                            if (popups != null) {

                                for (int counter = popups.size() - 1;

                                                   counter >= 0; counter--) {

                                    popups.get(counter)._dispose();

                                }

                            }

                        }

                    });

                }

                if(cache.size() < MAX_CACHE_SIZE) {

                    cache.add(popup);

                } else {

                    popup._dispose();

                }

            }

        }

        //

        // Popup methods

        //

        public void hide() {

            super.hide();

            recycleHeavyWeightPopup(this);

        }

        /**

         * As we recycle the <code>Window</code>, we don't want to dispose it,

         * thus this method does nothing, instead use <code>_dipose</code>

         * which will handle the disposing.

         */

        void dispose() {

        }

        void _dispose() {

            super.dispose();

        }

    }

    /**

     * ContainerPopup consolidates the common code used in the light/medium

     * weight implementations of <code>Popup</code>.

     */

    private static class ContainerPopup extends Popup {

        /** Component we are to be added to. */

        Component owner;

        /** Desired x location. */

        int x;

        /** Desired y location. */

        int y;

        public void hide() {

            Component component = getComponent();

            if (component != null) {

                Container parent = component.getParent();

                if (parent != null) {

                    Rectangle bounds = component.getBounds();

                    parent.remove(component);

                    parent.repaint(bounds.x, bounds.y, bounds.width,

                                   bounds.height);

                }

            }

            owner = null;

        }

        public void pack() {

            Component component = getComponent();

            if (component != null) {

                component.setSize(component.getPreferredSize());

            }

        }

        void reset(Component owner, Component contents, int ownerX,

                   int ownerY) {

            if ((owner instanceof JFrame) || (owner instanceof JDialog) ||

                                                 (owner instanceof JWindow)) {

                // Force the content to be added to the layered pane, otherwise

                // we'll get an exception when adding to the RootPaneContainer.

                owner = ((RootPaneContainer)owner).getLayeredPane();

            }

            super.reset(owner, contents, ownerX, ownerY);

            x = ownerX;

            y = ownerY;

            this.owner = owner;

        }