/*
 * Copyright (c) 1996, 2019, 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 sun.awt.windows;

import java.awt.*;
import java.awt.peer.*;
import java.awt.image.VolatileImage;
import sun.awt.RepaintArea;
import sun.awt.image.SunVolatileImage;
import sun.awt.image.ToolkitImage;
import java.awt.image.BufferedImage;
import java.awt.image.ImageProducer;
import java.awt.image.ImageObserver;
import java.awt.image.ColorModel;
import java.awt.event.PaintEvent;
import java.awt.event.InvocationEvent;
import java.awt.event.KeyEvent;
import java.awt.event.FocusEvent;
import java.awt.event.MouseEvent;
import java.awt.event.MouseWheelEvent;
import java.awt.event.InputEvent;
import sun.awt.Win32GraphicsConfig;
import sun.awt.Win32GraphicsEnvironment;
import sun.java2d.InvalidPipeException;
import sun.java2d.SurfaceData;
import sun.java2d.ScreenUpdateManager;
import sun.java2d.d3d.D3DSurfaceData;
import sun.java2d.opengl.OGLSurfaceData;
import sun.java2d.pipe.Region;
import sun.awt.PaintEventDispatcher;
import sun.awt.SunToolkit;
import sun.awt.event.IgnorePaintEvent;

import java.awt.dnd.DropTarget;
import java.awt.dnd.peer.DropTargetPeer;
import java.awt.geom.AffineTransform;
import sun.awt.AWTAccessor;

import sun.util.logging.PlatformLogger;

public abstract class WComponentPeer extends WObjectPeer
    implements ComponentPeer, DropTargetPeer
{
    
Handle to native window
/**
     * Handle to native window
     */
    protected volatile long hwnd;

    private static final PlatformLogger log = PlatformLogger.getLogger("sun.awt.windows.WComponentPeer");
    private static final PlatformLogger shapeLog = PlatformLogger.getLogger("sun.awt.windows.shape.WComponentPeer");
    private static final PlatformLogger focusLog = PlatformLogger.getLogger("sun.awt.windows.focus.WComponentPeer");

    // ComponentPeer implementation
    SurfaceData surfaceData;

    private RepaintArea paintArea;

    protected Win32GraphicsConfig winGraphicsConfig;

    boolean isLayouting = false;
    boolean paintPending = false;
    int     oldWidth = -1;
    int     oldHeight = -1;
    private int numBackBuffers = 0;
    private VolatileImage backBuffer = null;
    private BufferCapabilities backBufferCaps = null;

    // foreground, background and color are cached to avoid calling back
    // into the Component.
    private Color foreground;
    private Color background;
    private Font font;

    @Override
    public native boolean isObscured();
    @Override
    public boolean canDetermineObscurity() { return true; }

    // DropTarget support

    int nDropTargets;
    long nativeDropTargetContext; // native pointer

    private synchronized native void pShow();
    synchronized native void hide();
    synchronized native void enable();
    synchronized native void disable();

    public long getHWnd() {
        return hwnd;
    }

    /* New 1.1 API */
    @Override
    public native Point getLocationOnScreen();

    /* New 1.1 API */
    @Override
    public void setVisible(boolean b) {
        if (b) {
            show();
        } else {
            hide();
        }
    }

    public void show() {
        Dimension s = ((Component)target).getSize();
        oldHeight = s.height;
        oldWidth = s.width;
        pShow();
    }

    /* New 1.1 API */
    @Override
    public void setEnabled(boolean b) {
        if (b) {
            enable();
        } else {
            disable();
        }
    }

    public int serialNum = 0;

    private native void reshapeNoCheck(int x, int y, int width, int height);

    /* New 1.1 API */
    @Override
    public void setBounds(int x, int y, int width, int height, int op) {
        // Should set paintPending before reahape to prevent
        // thread race between paint events
        // Native components do redraw after resize
        paintPending = (width != oldWidth) || (height != oldHeight);

        if ( (op & NO_EMBEDDED_CHECK) != 0 ) {
            reshapeNoCheck(x, y, width, height);
        } else {
            reshape(x, y, width, height);
        }
        if ((width != oldWidth) || (height != oldHeight)) {
            // Only recreate surfaceData if this setBounds is called
            // for a resize; a simple move should not trigger a recreation
            try {
                replaceSurfaceData();
            } catch (InvalidPipeException e) {
                // REMIND : what do we do if our surface creation failed?
            }
            oldWidth = width;
            oldHeight = height;
        }

        serialNum++;
    }

    /*
     * Called from native code (on Toolkit thread) in order to
     * dynamically layout the Container during resizing
     */
    void dynamicallyLayoutContainer() {
        // If we got the WM_SIZING, this must be a Container, right?
        // In fact, it must be the top-level Container.
        if (log.isLoggable(PlatformLogger.Level.FINE)) {
            Container parent = WToolkit.getNativeContainer((Component)target);
            if (parent != null) {
                log.fine("Assertion (parent == null) failed");
            }
        }
        final Container cont = (Container)target;

        WToolkit.executeOnEventHandlerThread(cont, new Runnable() {
            @Override
            public void run() {
                // Discarding old paint events doesn't seem to be necessary.
                cont.invalidate();
                cont.validate();

                if (surfaceData instanceof D3DSurfaceData.D3DWindowSurfaceData ||
                    surfaceData instanceof OGLSurfaceData)
                {
                    // When OGL or D3D is enabled, it is necessary to
                    // replace the SurfaceData for each dynamic layout
                    // request so that the viewport stays in sync
                    // with the window bounds.
                    try {
                        replaceSurfaceData();
                    } catch (InvalidPipeException e) {
                        // REMIND: this is unlikely to occur for OGL, but
                        // what do we do if surface creation fails?
                    }
                }

                // Forcing a paint here doesn't seem to be necessary.
                // paintDamagedAreaImmediately();
            }
        });
    }

    /*
     * Paints any portion of the component that needs updating
     * before the call returns (similar to the Win32 API UpdateWindow)
     */
    void paintDamagedAreaImmediately() {
        // force Windows to send any pending WM_PAINT events so
        // the damage area is updated on the Java side
        updateWindow();
        // make sure paint events are transferred to main event queue
        // for coalescing
        SunToolkit.flushPendingEvents();
        // paint the damaged area
        paintArea.paint(target, shouldClearRectBeforePaint());
    }

    synchronized native void updateWindow();

    @Override
    public void paint(Graphics g) {
        ((Component)target).paint(g);
    }

    public void repaint(long tm, int x, int y, int width, int height) {
    }

    private static final double BANDING_DIVISOR = 4.0;
    private native int[] createPrintedPixels(int srcX, int srcY,
                                             int srcW, int srcH,
                                             int alpha);
    @Override
    public void print(Graphics g) {

        Component comp = (Component)target;

        // To conserve memory usage, we will band the image.

        int totalW = comp.getWidth();
        int totalH = comp.getHeight();

        int hInc = (int)(totalH / BANDING_DIVISOR);
        if (hInc == 0) {
            hInc = totalH;
        }

        for (int startY = 0; startY < totalH; startY += hInc) {
            int endY = startY + hInc - 1;
            if (endY >= totalH) {
                endY = totalH - 1;
            }
            int h = endY - startY + 1;

            Color bgColor = comp.getBackground();
            int[] pix = createPrintedPixels(0, startY, totalW, h,
                                            bgColor == null ? 255 : bgColor.getAlpha());
            if (pix != null) {
                BufferedImage bim = new BufferedImage(totalW, h,
                                              BufferedImage.TYPE_INT_ARGB);
                bim.setRGB(0, 0, totalW, h, pix, 0, totalW);
                g.drawImage(bim, 0, startY, null);
                bim.flush();
            }
        }

        comp.print(g);
    }

    @Override
    public void coalescePaintEvent(PaintEvent e) {
        Rectangle r = e.getUpdateRect();
        if (!(e instanceof IgnorePaintEvent)) {
            paintArea.add(r, e.getID());
        }

        if (log.isLoggable(PlatformLogger.Level.FINEST)) {
            switch(e.getID()) {
            case PaintEvent.UPDATE:
                log.finest("coalescePaintEvent: UPDATE: add: x = " +
                    r.x + ", y = " + r.y + ", width = " + r.width + ", height = " + r.height);
                return;
            case PaintEvent.PAINT:
                log.finest("coalescePaintEvent: PAINT: add: x = " +
                    r.x + ", y = " + r.y + ", width = " + r.width + ", height = " + r.height);
                return;
            }
        }
    }

    public synchronized native void reshape(int x, int y, int width, int height);

    // returns true if the event has been handled and shouldn't be propagated
    // though handleEvent method chain - e.g. WTextFieldPeer returns true
    // on handling '\n' to prevent it from being passed to native code
    public boolean handleJavaKeyEvent(KeyEvent e) { return false; }

    public void handleJavaMouseEvent(MouseEvent e) {
        switch (e.getID()) {
          case MouseEvent.MOUSE_PRESSED:
              // Note that Swing requests focus in its own mouse event handler.
              if (target == e.getSource() &&
                  !((Component)target).isFocusOwner() &&
                  WKeyboardFocusManagerPeer.shouldFocusOnClick((Component)target))
              {
                  WKeyboardFocusManagerPeer.requestFocusFor((Component)target,
                                                            FocusEvent.Cause.MOUSE_EVENT);
              }
              break;
        }
    }

    native void nativeHandleEvent(AWTEvent e);

    @Override
    @SuppressWarnings("fallthrough")
    public void handleEvent(AWTEvent e) {
        int id = e.getID();

        if ((e instanceof InputEvent) && !((InputEvent)e).isConsumed() &&
            ((Component)target).isEnabled())
        {
            if (e instanceof MouseEvent && !(e instanceof MouseWheelEvent)) {
                handleJavaMouseEvent((MouseEvent) e);
            } else if (e instanceof KeyEvent) {
                if (handleJavaKeyEvent((KeyEvent)e)) {
                    return;
                }
            }
        }

        switch(id) {
            case PaintEvent.PAINT:
                // Got native painting
                paintPending = false;
                // Fallthrough to next statement
            case PaintEvent.UPDATE:
                // Skip all painting while layouting and all UPDATEs
                // while waiting for native paint
                if (!isLayouting && ! paintPending) {
                    paintArea.paint(target,shouldClearRectBeforePaint());
                }
                return;
            case FocusEvent.FOCUS_LOST:
            case FocusEvent.FOCUS_GAINED:
                handleJavaFocusEvent((FocusEvent)e);
            default:
            break;
        }

        // Call the native code
        nativeHandleEvent(e);
    }

    void handleJavaFocusEvent(FocusEvent fe) {
        if (focusLog.isLoggable(PlatformLogger.Level.FINER)) {
            focusLog.finer(fe.toString());
        }
        setFocus(fe.getID() == FocusEvent.FOCUS_GAINED);
    }

    native void setFocus(boolean doSetFocus);

    @Override
    public Dimension getMinimumSize() {
        return ((Component)target).getSize();
    }

    @Override
    public Dimension getPreferredSize() {
        return getMinimumSize();
    }

    // Do nothing for heavyweight implementation
    @Override
    public void layout() {}

    public Rectangle getBounds() {
        return ((Component)target).getBounds();
    }

    @Override
    public boolean isFocusable() {
        return false;
    }

    /*
     * Return the GraphicsConfiguration associated with this peer, either
     * the locally stored winGraphicsConfig, or that of the target Component.
     */
    @Override
    public GraphicsConfiguration getGraphicsConfiguration() {
        if (winGraphicsConfig != null) {
            return winGraphicsConfig;
        }
        else {
            // we don't need a treelock here, since
            // Component.getGraphicsConfiguration() gets it itself.
            return ((Component)target).getGraphicsConfiguration();
        }
    }

    public SurfaceData getSurfaceData() {
        return surfaceData;
    }

    
Creates new surfaceData object and invalidates the previous
surfaceData object.
Replacing the surface data should never lock on any resources which are
required by other threads which may have them and may require
the tree-lock.
This is a degenerate version of replaceSurfaceData(numBackBuffers), so
just call that version with our current numBackBuffers.
/**
     * Creates new surfaceData object and invalidates the previous
     * surfaceData object.
     * Replacing the surface data should never lock on any resources which are
     * required by other threads which may have them and may require
     * the tree-lock.
     * This is a degenerate version of replaceSurfaceData(numBackBuffers), so
     * just call that version with our current numBackBuffers.
     */
    public void replaceSurfaceData() {
        replaceSurfaceData(this.numBackBuffers, this.backBufferCaps);
    }

    public void createScreenSurface(boolean isResize)
    {
        Win32GraphicsConfig gc = (Win32GraphicsConfig)getGraphicsConfiguration();
        ScreenUpdateManager mgr = ScreenUpdateManager.getInstance();

        surfaceData = mgr.createScreenSurface(gc, this, numBackBuffers, isResize);
    }


    
Multi-buffer version of replaceSurfaceData.  This version is called
by createBuffers(), which needs to acquire the same locks in the same
order, but also needs to perform additional functions inside the
locks.
/**
     * Multi-buffer version of replaceSurfaceData.  This version is called
     * by createBuffers(), which needs to acquire the same locks in the same
     * order, but also needs to perform additional functions inside the
     * locks.
     */
    public void replaceSurfaceData(int newNumBackBuffers,
                                   BufferCapabilities caps)
    {
        SurfaceData oldData = null;
        VolatileImage oldBB = null;
        synchronized(((Component)target).getTreeLock()) {
            synchronized(this) {
                if (pData == 0) {
                    return;
                }
                numBackBuffers = newNumBackBuffers;
                ScreenUpdateManager mgr = ScreenUpdateManager.getInstance();
                oldData = surfaceData;
                mgr.dropScreenSurface(oldData);
                createScreenSurface(true);
                if (oldData != null) {
                    oldData.invalidate();
                }

                oldBB = backBuffer;
                if (numBackBuffers > 0) {
                    // set the caps first, they're used when creating the bb
                    backBufferCaps = caps;
                    Win32GraphicsConfig gc =
                        (Win32GraphicsConfig)getGraphicsConfiguration();
                    backBuffer = gc.createBackBuffer(this);
                } else if (backBuffer != null) {
                    backBufferCaps = null;
                    backBuffer = null;
                }
            }
        }
        // it would be better to do this before we create new ones,
        // but then we'd run into deadlock issues
        if (oldData != null) {
            oldData.flush();
            // null out the old data to make it collected faster
            oldData = null;
        }
        if (oldBB != null) {
            oldBB.flush();
            // null out the old data to make it collected faster
            oldData = null;
        }
    }

    public void replaceSurfaceDataLater() {
        Runnable r = new Runnable() {
            @Override
            public void run() {
                // Shouldn't do anything if object is disposed in meanwhile
                // No need for sync as disposeAction in Window is performed
                // on EDT
                if (!isDisposed()) {
                    try {
                        replaceSurfaceData();
                    } catch (InvalidPipeException e) {
                        // REMIND : what do we do if our surface creation failed?
                    }
                }
            }
        };
        Component c = (Component)target;
        // Fix 6255371.
        if (!PaintEventDispatcher.getPaintEventDispatcher().queueSurfaceDataReplacing(c, r)) {
            postEvent(new InvocationEvent(c, r));
        }
    }

    @Override
    public boolean updateGraphicsData(GraphicsConfiguration gc) {
        winGraphicsConfig = (Win32GraphicsConfig)gc;
        try {
            replaceSurfaceData();
        } catch (InvalidPipeException e) {
            // REMIND : what do we do if our surface creation failed?
        }
        return false;
    }

    //This will return null for Components not yet added to a Container
    @Override
    public ColorModel getColorModel() {
        GraphicsConfiguration gc = getGraphicsConfiguration();
        if (gc != null) {
            return gc.getColorModel();
        }
        else {
            return null;
        }
    }

    //This will return null for Components not yet added to a Container
    public ColorModel getDeviceColorModel() {
        Win32GraphicsConfig gc =
            (Win32GraphicsConfig)getGraphicsConfiguration();
        if (gc != null) {
            return gc.getDeviceColorModel();
        }
        else {
            return null;
        }
    }

    //Returns null for Components not yet added to a Container
    public ColorModel getColorModel(int transparency) {
//      return WToolkit.config.getColorModel(transparency);
        GraphicsConfiguration gc = getGraphicsConfiguration();
        if (gc != null) {
            return gc.getColorModel(transparency);
        }
        else {
            return null;
        }
    }

    // fallback default font object
    static final Font defaultFont = new Font(Font.DIALOG, Font.PLAIN, 12);

    @Override
    public Graphics getGraphics() {
        if (isDisposed()) {
            return null;
        }

        Component target = (Component)getTarget();
        Window window = SunToolkit.getContainingWindow(target);
        if (window != null) {
            final WWindowPeer wpeer = AWTAccessor.getComponentAccessor()
                                                 .getPeer(window);
            if (wpeer != null) {
                Graphics g = wpeer.getTranslucentGraphics();
                // getTranslucentGraphics() returns non-null value for non-opaque windows only
                if (g != null) {
                    // Non-opaque windows do not support heavyweight children.
                    // Redirect all painting to the Window's Graphics instead.
                    // The caller is responsible for calling the
                    // WindowPeer.updateWindow() after painting has finished.
                    int x = 0, y = 0;
                    for (Component c = target; c != window; c = c.getParent()) {
                        x += c.getX();
                        y += c.getY();
                    }

                    g.translate(x, y);
                    g.clipRect(0, 0, target.getWidth(), target.getHeight());

                    return g;
                }
            }
        }

        SurfaceData surfaceData = this.surfaceData;
        if (surfaceData != null) {
            /* Fix for bug 4746122. Color and Font shouldn't be null */
            Color bgColor = background;
            if (bgColor == null) {
                bgColor = SystemColor.window;
            }
            Color fgColor = foreground;
            if (fgColor == null) {
                fgColor = SystemColor.windowText;
            }
            Font font = this.font;
            if (font == null) {
                font = defaultFont;
            }
            ScreenUpdateManager mgr =
                ScreenUpdateManager.getInstance();
            return mgr.createGraphics(surfaceData, this, fgColor,
                                      bgColor, font);
        }
        return null;
    }
    @Override
    public FontMetrics getFontMetrics(Font font) {
        return WFontMetrics.getFontMetrics(font);
    }

    private synchronized native void _dispose();
    @Override
    protected void disposeImpl() {
        SurfaceData oldData = surfaceData;
        surfaceData = null;
        ScreenUpdateManager.getInstance().dropScreenSurface(oldData);
        oldData.invalidate();
        // remove from updater before calling targetDisposedPeer
        WToolkit.targetDisposedPeer(target, this);
        _dispose();
    }

    public void disposeLater() {
        postEvent(new InvocationEvent(target, new Runnable() {
            @Override
            public void run() {
                dispose();
            }
        }));
    }

    @Override
    public synchronized void setForeground(Color c) {
        foreground = c;
        _setForeground(c.getRGB());
    }

    @Override
    public synchronized void setBackground(Color c) {
        background = c;
        _setBackground(c.getRGB());
    }

    
This method is intentionally not synchronized as it is called while
holding other locks.
See Also:
validate.validate/**
     * This method is intentionally not synchronized as it is called while
     * holding other locks.
     *
     * @see sun.java2d.d3d.D3DScreenUpdateManager#validate
     */
    public Color getBackgroundNoSync() {
        return background;
    }

    private native void _setForeground(int rgb);
    private native void _setBackground(int rgb);

    @Override
    public synchronized void setFont(Font f) {
        font = f;
        _setFont(f);
    }
    synchronized native void _setFont(Font f);
    @Override
    public void updateCursorImmediately() {
        WGlobalCursorManager.getCursorManager().updateCursorImmediately();
    }

    // TODO: consider moving it to KeyboardFocusManagerPeerImpl
    @Override
    public boolean requestFocus(Component lightweightChild, boolean temporary,
                                boolean focusedWindowChangeAllowed, long time,
                                FocusEvent.Cause cause)
    {
        if (WKeyboardFocusManagerPeer.
            processSynchronousLightweightTransfer((Component)target, lightweightChild, temporary,
                                                  focusedWindowChangeAllowed, time))
        {
            return true;
        }

        int result = WKeyboardFocusManagerPeer
            .shouldNativelyFocusHeavyweight((Component)target, lightweightChild,
                                            temporary, focusedWindowChangeAllowed,
                                            time, cause);

        switch (result) {
          case WKeyboardFocusManagerPeer.SNFH_FAILURE:
              return false;
          case WKeyboardFocusManagerPeer.SNFH_SUCCESS_PROCEED:
              if (focusLog.isLoggable(PlatformLogger.Level.FINER)) {
                  focusLog.finer("Proceeding with request to " + lightweightChild + " in " + target);
              }
              Window parentWindow = SunToolkit.getContainingWindow((Component)target);
              if (parentWindow == null) {
                  return rejectFocusRequestHelper("WARNING: Parent window is null");
              }
              final WWindowPeer wpeer = AWTAccessor.getComponentAccessor()
                                                   .getPeer(parentWindow);
              if (wpeer == null) {
                  return rejectFocusRequestHelper("WARNING: Parent window's peer is null");
              }
              boolean res = wpeer.requestWindowFocus(cause);

              if (focusLog.isLoggable(PlatformLogger.Level.FINER)) {
                  focusLog.finer("Requested window focus: " + res);
              }
              // If parent window can be made focused and has been made focused(synchronously)
              // then we can proceed with children, otherwise we retreat.
              if (!(res && parentWindow.isFocused())) {
                  return rejectFocusRequestHelper("Waiting for asynchronous processing of the request");
              }
              return WKeyboardFocusManagerPeer.deliverFocus(lightweightChild,
                                                            (Component)target,
                                                            temporary,
                                                            focusedWindowChangeAllowed,
                                                            time, cause);

          case WKeyboardFocusManagerPeer.SNFH_SUCCESS_HANDLED:
              // Either lightweight or excessive request - all events are generated.
              return true;
        }
        return false;
    }

    private boolean rejectFocusRequestHelper(String logMsg) {
        if (focusLog.isLoggable(PlatformLogger.Level.FINER)) {
            focusLog.finer(logMsg);
        }
        WKeyboardFocusManagerPeer.removeLastFocusRequest((Component)target);
        return false;
    }

    @Override
    public Image createImage(ImageProducer producer) {
        return new ToolkitImage(producer);
    }

    @Override
    public Image createImage(int width, int height) {
        Win32GraphicsConfig gc =
            (Win32GraphicsConfig)getGraphicsConfiguration();
        return gc.createAcceleratedImage((Component)target, width, height);
    }

    @Override
    public VolatileImage createVolatileImage(int width, int height) {
        return new SunVolatileImage((Component)target, width, height);
    }

    @Override
    public boolean prepareImage(Image img, int w, int h, ImageObserver o) {
        return Toolkit.getDefaultToolkit().prepareImage(img, w, h, o);
    }

    @Override
    public int checkImage(Image img, int w, int h, ImageObserver o) {
        return Toolkit.getDefaultToolkit().checkImage(img, w, h, o);
    }

    // Object overrides

    public String toString() {
        return getClass().getName() + "[" + target + "]";
    }

    // Toolkit & peer internals

    private int updateX1, updateY1, updateX2, updateY2;

    WComponentPeer(Component target) {
        this.target = target;
        this.paintArea = new RepaintArea();
        create(getNativeParent());
        // fix for 5088782: check if window object is created successfully
        checkCreation();

        createScreenSurface(false);
        initialize();
        start();  // Initialize enable/disable state, turn on callbacks
    }
    abstract void create(WComponentPeer parent);

    
Gets the native parent of this peer. We use the term "parent" explicitly,
because we override the method in top-level window peer implementations.
Returns:
the parent container/owner of this peer./**
     * Gets the native parent of this peer. We use the term "parent" explicitly,
     * because we override the method in top-level window peer implementations.
     *
     * @return the parent container/owner of this peer.
     */
    WComponentPeer getNativeParent() {
        Container parent = SunToolkit.getNativeContainer((Component) target);
        return (WComponentPeer) WToolkit.targetToPeer(parent);
    }

    protected void checkCreation()
    {
        if ((hwnd == 0) || (pData == 0))
        {
            if (createError != null)
            {
                throw createError;
            }
            else
            {
                throw new InternalError("couldn't create component peer");
            }
        }
    }

    synchronized native void start();

    void initialize() {
        if (((Component)target).isVisible()) {
            show();  // the wnd starts hidden
        }
        Color fg = ((Component)target).getForeground();
        if (fg != null) {
            setForeground(fg);
        }
        // Set background color in C++, to avoid inheriting a parent's color.
        Font  f = ((Component)target).getFont();
        if (f != null) {
            setFont(f);
        }
        if (! ((Component)target).isEnabled()) {
            disable();
        }
        Rectangle r = ((Component)target).getBounds();
        setBounds(r.x, r.y, r.width, r.height, SET_BOUNDS);
    }

    // Callbacks for window-system events to the frame

    // Invoke a update() method call on the target
    void handleRepaint(int x, int y, int w, int h) {
        // Repaints are posted from updateClient now...
    }

    // Invoke a paint() method call on the target, after clearing the
    // damaged area.
    void handleExpose(int x, int y, int w, int h) {
        // Bug ID 4081126 & 4129709 - can't do the clearRect() here,
        // since it interferes with the java thread working in the
        // same window on multi-processor NT machines.

        postPaintIfNecessary(x, y, w, h);
    }

    /* Invoke a paint() method call on the target, without clearing the
     * damaged area.  This is normally called by a native control after
     * it has painted itself.
     *
     * NOTE: This is called on the privileged toolkit thread. Do not
     *       call directly into user code using this thread!
     */
    public void handlePaint(int x, int y, int w, int h) {
        postPaintIfNecessary(x, y, w, h);
    }

    private void postPaintIfNecessary(int x, int y, int w, int h) {
        if ( !AWTAccessor.getComponentAccessor().getIgnoreRepaint( (Component) target) ) {
            PaintEvent event = PaintEventDispatcher.getPaintEventDispatcher().
                createPaintEvent((Component)target, x, y, w, h);
            if (event != null) {
                postEvent(event);
            }
        }
    }

    /*
     * Post an event. Queue it for execution by the callback thread.
     */
    void postEvent(AWTEvent event) {
        preprocessPostEvent(event);
        WToolkit.postEvent(WToolkit.targetToAppContext(target), event);
    }

    void preprocessPostEvent(AWTEvent event) {}

    // Routines to support deferred window positioning.
    public void beginLayout() {
        // Skip all painting till endLayout
        isLayouting = true;
    }

    public void endLayout() {
        if(!paintArea.isEmpty() && !paintPending &&
            !((Component)target).getIgnoreRepaint()) {
            // if not waiting for native painting repaint damaged area
            postEvent(new PaintEvent((Component)target, PaintEvent.PAINT,
                          new Rectangle()));
        }
        isLayouting = false;
    }

    public native void beginValidate();
    public native void endValidate();

    
register a DropTarget with this native peer
/**
     * register a DropTarget with this native peer
     */

    @Override
    public synchronized void addDropTarget(DropTarget dt) {
        if (nDropTargets == 0) {
            nativeDropTargetContext = addNativeDropTarget();
        }
        nDropTargets++;
    }

    
unregister a DropTarget with this native peer
/**
     * unregister a DropTarget with this native peer
     */

    @Override
    public synchronized void removeDropTarget(DropTarget dt) {
        nDropTargets--;
        if (nDropTargets == 0) {
            removeNativeDropTarget();
            nativeDropTargetContext = 0;
        }
    }

    
add the native peer's AwtDropTarget COM object
Returns:
reference to AwtDropTarget object/**
     * add the native peer's AwtDropTarget COM object
     * @return reference to AwtDropTarget object
     */

    native long addNativeDropTarget();

    
remove the native peer's AwtDropTarget COM object
/**
     * remove the native peer's AwtDropTarget COM object
     */

    native void removeNativeDropTarget();
    native boolean nativeHandlesWheelScrolling();

    @Override
    public boolean handlesWheelScrolling() {
        // should this be cached?
        return nativeHandlesWheelScrolling();
    }

    // Returns true if we are inside begin/endLayout and
    // are waiting for native painting
    public boolean isPaintPending() {
        return paintPending && isLayouting;
    }

    
The following multibuffering-related methods delegate to our
associated GraphicsConfig (Win or WGL) to handle the appropriate
native windowing system specific actions.
/**
     * The following multibuffering-related methods delegate to our
     * associated GraphicsConfig (Win or WGL) to handle the appropriate
     * native windowing system specific actions.
     */

    @Override
    public void createBuffers(int numBuffers, BufferCapabilities caps)
        throws AWTException
    {
        Win32GraphicsConfig gc =
            (Win32GraphicsConfig)getGraphicsConfiguration();
        gc.assertOperationSupported((Component)target, numBuffers, caps);

        // Re-create the primary surface with the new number of back buffers
        try {
            replaceSurfaceData(numBuffers - 1, caps);
        } catch (InvalidPipeException e) {
            throw new AWTException(e.getMessage());
        }
    }

    @Override
    public void destroyBuffers() {
        replaceSurfaceData(0, null);
    }

    @Override
    public void flip(int x1, int y1, int x2, int y2,
                                  BufferCapabilities.FlipContents flipAction)
    {
        VolatileImage backBuffer = this.backBuffer;
        if (backBuffer == null) {
            throw new IllegalStateException("Buffers have not been created");
        }
        Win32GraphicsConfig gc =
            (Win32GraphicsConfig)getGraphicsConfiguration();
        gc.flip(this, (Component)target, backBuffer, x1, y1, x2, y2, flipAction);
    }

    @Override
    public synchronized Image getBackBuffer() {
        Image backBuffer = this.backBuffer;
        if (backBuffer == null) {
            throw new IllegalStateException("Buffers have not been created");
        }
        return backBuffer;
    }
    public BufferCapabilities getBackBufferCaps() {
        return backBufferCaps;
    }
    public int getBackBuffersNum() {
        return numBackBuffers;
    }

    /* override and return false on components that DO NOT require
       a clearRect() before painting (i.e. native components) */
    public boolean shouldClearRectBeforePaint() {
        return true;
    }

    native void pSetParent(ComponentPeer newNativeParent);

    
See Also:
reparent.reparent/**
     * @see java.awt.peer.ComponentPeer#reparent
     */
    @Override
    public void reparent(ContainerPeer newNativeParent) {
        pSetParent(newNativeParent);
    }

    
See Also:
isReparentSupported.isReparentSupported/**
     * @see java.awt.peer.ComponentPeer#isReparentSupported
     */
    @Override
    public boolean isReparentSupported() {
        return true;
    }

    public void setBoundsOperation(int operation) {
    }

    private volatile boolean isAccelCapable = true;

    
Returns whether this component is capable of being hw accelerated. More specifically, whether rendering to this component or a BufferStrategy's back-buffer for this component can be hw accelerated. Conditions which could prevent hw acceleration include the toplevel window containing this component being 
PERPIXEL_TRANSLUCENT. Another condition is if Xor paint mode was detected when rendering to an on-screen accelerated surface associated with this peer. in this case both on- and off-screen acceleration for this peer is disabled. 
See Also:
WindowTranslucency.PERPIXEL_TRANSLUCENT
Returns:
true if this component is capable of being hw accelerated, false otherwise/**
     * Returns whether this component is capable of being hw accelerated.
     * More specifically, whether rendering to this component or a
     * BufferStrategy's back-buffer for this component can be hw accelerated.
     *
     * Conditions which could prevent hw acceleration include the toplevel
     * window containing this component being
     * {@link GraphicsDevice.WindowTranslucency#PERPIXEL_TRANSLUCENT
     * PERPIXEL_TRANSLUCENT}.
     *
     * Another condition is if Xor paint mode was detected when rendering
     * to an on-screen accelerated surface associated with this peer.
     * in this case both on- and off-screen acceleration for this peer is
     * disabled.
     *
     * @return {@code true} if this component is capable of being hw
     * accelerated, {@code false} otherwise
     * @see GraphicsDevice.WindowTranslucency#PERPIXEL_TRANSLUCENT
     */
    public boolean isAccelCapable() {
        if (!isAccelCapable ||
            !isContainingTopLevelAccelCapable((Component)target))
        {
            return false;
        }

        boolean isTranslucent =
            SunToolkit.isContainingTopLevelTranslucent((Component)target);
        // D3D/OGL and translucent windows interacted poorly in Windows XP;
        // these problems are no longer present in Vista
        return !isTranslucent || Win32GraphicsEnvironment.isVistaOS();
    }

    
Disables acceleration for this peer.
/**
     * Disables acceleration for this peer.
     */
    public void disableAcceleration() {
        isAccelCapable = false;
    }


    native void setRectangularShape(int lox, int loy, int hix, int hiy,
                     Region region);


    // REMIND: Temp workaround for issues with using HW acceleration
    // in the browser on Vista when DWM is enabled.
    // @return true if the toplevel container is not an EmbeddedFrame or
    // if this EmbeddedFrame is acceleration capable, false otherwise
    private static final boolean isContainingTopLevelAccelCapable(Component c) {
        while (c != null && !(c instanceof WEmbeddedFrame)) {
            c = c.getParent();
        }
        if (c == null) {
            return true;
        }
        final WEmbeddedFramePeer peer = AWTAccessor.getComponentAccessor()
                                                   .getPeer(c);
        return peer.isAccelCapable();
    }

    
Applies the shape to the native component window.
Since:
1.7/**
     * Applies the shape to the native component window.
     * @since 1.7
     */
    @Override
    public void applyShape(Region shape) {
        if (shapeLog.isLoggable(PlatformLogger.Level.FINER)) {
            shapeLog.finer("*** INFO: Setting shape: PEER: " + this
                            + "; TARGET: " + target
                            + "; SHAPE: " + shape);
        }

        if (shape != null) {
            AffineTransform tx = winGraphicsConfig.getDefaultTransform();
            double scaleX = tx.getScaleX();
            double scaleY = tx.getScaleY();
            if (scaleX != 1 || scaleY != 1) {
                shape = shape.getScaledRegion(scaleX, scaleY);
            }
            setRectangularShape(shape.getLoX(), shape.getLoY(), shape.getHiX(), shape.getHiY(),
                    (shape.isRectangular() ? null : shape));
        } else {
            setRectangularShape(0, 0, 0, 0, null);
        }
    }

    
Lowers this component at the bottom of the above component. If the above parameter
is null then the method places this component at the top of the Z-order.
/**
     * Lowers this component at the bottom of the above component. If the above parameter
     * is null then the method places this component at the top of the Z-order.
     */
    @Override
    public void setZOrder(ComponentPeer above) {
        long aboveHWND = (above != null) ? ((WComponentPeer)above).getHWnd() : 0;

        setZOrder(aboveHWND);
    }

    private native void setZOrder(long above);

    public boolean isLightweightFramePeer() {
        return false;
    }
}