/*
 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 */
package java.awt;

import java.io.IOException;
import java.awt.image.*;
import java.net.URL;
import java.net.URLConnection;
import java.io.File;
import sun.util.logging.PlatformLogger;
import sun.awt.image.SunWritableRaster;

/**
 * The splash screen can be displayed at application startup, before the
 * Java Virtual Machine (JVM) starts. The splash screen is displayed as an
 * undecorated window containing an image. You can use GIF, JPEG, or PNG files
 * for the image. Animation is supported for the GIF format, while transparency
 * is supported both for GIF and PNG. The window is positioned at the center
 * of the screen. The position on multi-monitor systems is not specified. It is
 * platform and implementation dependent. The splash screen window is closed
 * automatically as soon as the first window is displayed by Swing/AWT (may be
 * also closed manually using the Java API, see below).
 * <P>
 * If your application is packaged in a jar file, you can use the
 * "SplashScreen-Image" option in a manifest file to show a splash screen.
 * Place the image in the jar archive and specify the path in the option.
 * The path should not have a leading slash.
 * <BR>
 * For example, in the <code>manifest.mf</code> file:
 * <PRE>
 * Manifest-Version: 1.0
 * Main-Class: Test
 * SplashScreen-Image: filename.gif
 * </PRE>
 * <P>
 * If the Java implementation provides the command-line interface and you run
 * your application by using the command line or a shortcut, use the Java
 * application launcher option to show a splash screen. The Oracle reference
 * implementation allows you to specify the splash screen image location with
 * the {@code -splash:} option.
 * <BR>
 * For example:
 * <PRE>
 * java -splash:filename.gif Test
 * </PRE>
 * The command line interface has higher precedence over the manifest
 * setting.
 * <p>
 * The splash screen will be displayed as faithfully as possible to present the
 * whole splash screen image given the limitations of the target platform and
 * display.
 * <p>
 * It is implied that the specified image is presented on the screen "as is",
 * i.e. preserving the exact color values as specified in the image file. Under
 * certain circumstances, though, the presented image may differ, e.g. when
 * applying color dithering to present a 32 bits per pixel (bpp) image on a 16
 * or 8 bpp screen. The native platform display configuration may also affect
 * the colors of the displayed image (e.g. color profiles, etc.)
 * <p>
 * The {@code SplashScreen} class provides the API for controlling the splash
 * screen. This class may be used to close the splash screen, change the splash
 * screen image, get the splash screen native window position/size, and paint
 * in the splash screen. It cannot be used to create the splash screen. You
 * should use the options provided by the Java implementation for that.
 * <p>
 * This class cannot be instantiated. Only a single instance of this class
 * can exist, and it may be obtained by using the {@link #getSplashScreen()}
 * static method. In case the splash screen has not been created at
 * application startup via the command line or manifest file option,
 * the <code>getSplashScreen</code> method returns <code>null</code>.
 *
 * @author Oleg Semenov
 * @since 1.6
 */
public final class SplashScreen {

 SplashScreen(long ptr) { // non-public constructor
 splashPtr = ptr;
 }

 /**
 * Returns the {@code SplashScreen} object used for
 * Java startup splash screen control on systems that support display.
 *
 * @throws UnsupportedOperationException if the splash screen feature is not
 * supported by the current toolkit
 * @throws HeadlessException if {@code GraphicsEnvironment.isHeadless()}
 * returns true
 * @return the {@link SplashScreen} instance, or <code>null</code> if there is
 * none or it has already been closed
 */
 public static SplashScreen getSplashScreen() {
 synchronized (SplashScreen.class) {
 if (GraphicsEnvironment.isHeadless()) {
 throw new HeadlessException();
 }
 // SplashScreen class is now a singleton
 if (!wasClosed && theInstance == null) {
 java.security.AccessController.doPrivileged(
 new java.security.PrivilegedAction<Void>() {
 public Void run() {
 System.loadLibrary("splashscreen");
 return null;
 }
 });
 long ptr = _getInstance();
 if (ptr != 0 && _isVisible(ptr)) {
 theInstance = new SplashScreen(ptr);
 }
 }
 return theInstance;
 }
 }

 /**
 * Changes the splash screen image. The new image is loaded from the
 * specified URL; GIF, JPEG and PNG image formats are supported.
 * The method returns after the image has finished loading and the window
 * has been updated.
 * The splash screen window is resized according to the size of
 * the image and is centered on the screen.
 *
 * @param imageURL the non-<code>null</code> URL for the new
 * splash screen image
 * @throws NullPointerException if {@code imageURL} is <code>null</code>
 * @throws IOException if there was an error while loading the image
 * @throws IllegalStateException if the splash screen has already been
 * closed
 */
 public void setImageURL(URL imageURL) throws NullPointerException, IOException, IllegalStateException {
 checkVisible();
 URLConnection connection = imageURL.openConnection();
 connection.connect();
 int length = connection.getContentLength();
 java.io.InputStream stream = connection.getInputStream();
 byte[] buf = new byte[length];
 int off = 0;
 while(true) {
 // check for available data
 int available = stream.available();
 if (available <= 0) {
 // no data available... well, let's try reading one byte
 // we'll see what happens then
 available = 1;
 }
 // check for enough room in buffer, realloc if needed
 // the buffer always grows in size 2x minimum
 if (off + available > length) {
 length = off*2;
 if (off + available > length) {
 length = available+off;
 }
 byte[] oldBuf = buf;
 buf = new byte[length];
 System.arraycopy(oldBuf, 0, buf, 0, off);
 }
 // now read the data
 int result = stream.read(buf, off, available);
 if (result < 0) {
 break;
 }
 off += result;
 }
 synchronized(SplashScreen.class) {
 checkVisible();
 if (!_setImageData(splashPtr, buf)) {
 throw new IOException("Bad image format or i/o error when loading image");
 }
 this.imageURL = imageURL;
 }
 }

 private void checkVisible() {
 if (!isVisible()) {
 throw new IllegalStateException("no splash screen available");
 }
 }
 /**
 * Returns the current splash screen image.
 *
 * @return URL for the current splash screen image file
 * @throws IllegalStateException if the splash screen has already been closed
 */
 public URL getImageURL() throws IllegalStateException {
 synchronized (SplashScreen.class) {
 checkVisible();
 if (imageURL == null) {
 try {
 String fileName = _getImageFileName(splashPtr);
 String jarName = _getImageJarName(splashPtr);
 if (fileName != null) {
 if (jarName != null) {
 imageURL = new URL("jar:"+(new File(jarName).toURL().toString())+"!/"+fileName);
 } else {
 imageURL = new File(fileName).toURL();
 }
 }
 }
 catch(java.net.MalformedURLException e) {
 if (log.isLoggable(PlatformLogger.Level.FINE)) {
 log.fine("MalformedURLException caught in the getImageURL() method", e);
 }
 }
 }
 return imageURL;
 }
 }

 /**
 * Returns the bounds of the splash screen window as a {@link Rectangle}.
 * This may be useful if, for example, you want to replace the splash
 * screen with your window at the same location.
 * <p>
 * You cannot control the size or position of the splash screen.
 * The splash screen size is adjusted automatically when the image changes.
 * <p>
 * The image may contain transparent areas, and thus the reported bounds may
 * be larger than the visible splash screen image on the screen.
 *
 * @return a {@code Rectangle} containing the splash screen bounds
 * @throws IllegalStateException if the splash screen has already been closed
 */
 public Rectangle getBounds() throws IllegalStateException {
 synchronized (SplashScreen.class) {
 checkVisible();
 float scale = _getScaleFactor(splashPtr);
 Rectangle bounds = _getBounds(splashPtr);
 assert scale > 0;
 if (scale > 0 && scale != 1) {
 bounds.setSize((int) (bounds.getWidth() / scale),
 (int) (bounds.getHeight() / scale));
 }
 return bounds;
 }
 }

 /**
 * Returns the size of the splash screen window as a {@link Dimension}.
 * This may be useful if, for example,
 * you want to draw on the splash screen overlay surface.
 * <p>
 * You cannot control the size or position of the splash screen.
 * The splash screen size is adjusted automatically when the image changes.
 * <p>
 * The image may contain transparent areas, and thus the reported size may
 * be larger than the visible splash screen image on the screen.
 *
 * @return a {@link Dimension} object indicating the splash screen size
 * @throws IllegalStateException if the splash screen has already been closed
 */
 public Dimension getSize() throws IllegalStateException {
 return getBounds().getSize();
 }

 /**
 * Creates a graphics context (as a {@link Graphics2D} object) for the splash
 * screen overlay image, which allows you to draw over the splash screen.
 * Note that you do not draw on the main image but on the image that is
 * displayed over the main image using alpha blending. Also note that drawing
 * on the overlay image does not necessarily update the contents of splash
 * screen window. You should call {@code update()} on the
 * <code>SplashScreen</code> when you want the splash screen to be
 * updated immediately.
 * <p>
 * The pixel (0, 0) in the coordinate space of the graphics context
 * corresponds to the origin of the splash screen native window bounds (see
 * {@link #getBounds()}).
 *
 * @return graphics context for the splash screen overlay surface
 * @throws IllegalStateException if the splash screen has already been closed
 */
 public Graphics2D createGraphics() throws IllegalStateException {
 synchronized (SplashScreen.class) {
 checkVisible();
 if (image==null) {
 // get unscaled splash image size
 Dimension dim = _getBounds(splashPtr).getSize();
 image = new BufferedImage(dim.width, dim.height,
 BufferedImage.TYPE_INT_ARGB);
 }
 float scale = _getScaleFactor(splashPtr);
 Graphics2D g = image.createGraphics();
 assert (scale > 0);
 if (scale <= 0) {
 scale = 1;
 }
 g.scale(scale, scale);
 return g;
 }
 }

 /**
 * Updates the splash window with current contents of the overlay image.
 *
 * @throws IllegalStateException if the overlay image does not exist;
 * for example, if {@code createGraphics} has never been called,
 * or if the splash screen has already been closed
 */
 public void update() throws IllegalStateException {
 BufferedImage image;
 synchronized (SplashScreen.class) {
 checkVisible();
 image = this.image;
 }
 if (image == null) {
 throw new IllegalStateException("no overlay image available");
 }
 DataBuffer buf = image.getRaster().getDataBuffer();
 if (!(buf instanceof DataBufferInt)) {
 throw new AssertionError("Overlay image DataBuffer is of invalid type == "+buf.getClass().getName());
 }
 int numBanks = buf.getNumBanks();
 if (numBanks!=1) {
 throw new AssertionError("Invalid number of banks =="+numBanks+" in overlay image DataBuffer");
 }
 if (!(image.getSampleModel() instanceof SinglePixelPackedSampleModel)) {
 throw new AssertionError("Overlay image has invalid sample model == "+image.getSampleModel().getClass().getName());
 }
 SinglePixelPackedSampleModel sm = (SinglePixelPackedSampleModel)image.getSampleModel();
 int scanlineStride = sm.getScanlineStride();
 Rectangle rect = image.getRaster().getBounds();
 // Note that we steal the data array here, but just for reading
 // so we do not need to mark the DataBuffer dirty...
 int[] data = SunWritableRaster.stealData((DataBufferInt)buf, 0);
 synchronized(SplashScreen.class) {
 checkVisible();
 _update(splashPtr, data, rect.x, rect.y, rect.width, rect.height, scanlineStride);
 }
 }

 /**
 * Hides the splash screen, closes the window, and releases all associated
 * resources.
 *
 * @throws IllegalStateException if the splash screen has already been closed
 */
 public void close() throws IllegalStateException {
 synchronized (SplashScreen.class) {
 checkVisible();
 _close(splashPtr);
 image = null;
 SplashScreen.markClosed();
 }
 }

 static void markClosed() {
 synchronized (SplashScreen.class) {
 wasClosed = true;
 theInstance = null;
 }
 }


 /**
 * Determines whether the splash screen is visible. The splash screen may
 * be hidden using {@link #close()}, it is also hidden automatically when
 * the first AWT/Swing window is made visible.
 * <p>
 * Note that the native platform may delay presenting the splash screen
 * native window on the screen. The return value of {@code true} for this
 * method only guarantees that the conditions to hide the splash screen
 * window have not occurred yet.
 *
 * @return true if the splash screen is visible (has not been closed yet),
 * false otherwise
 */
 public boolean isVisible() {
 synchronized (SplashScreen.class) {
 return !wasClosed && _isVisible(splashPtr);
 }
 }

 private BufferedImage image; // overlay image

 private final long splashPtr; // pointer to native Splash structure
 private static boolean wasClosed = false;

 private URL imageURL;

 /**
 * The instance reference for the singleton.
 * (<code>null</code> if no instance exists yet.)
 *
 * @see #getSplashScreen
 * @see #close
 */
 private static SplashScreen theInstance = null;

 private static final PlatformLogger log = PlatformLogger.getLogger("java.awt.SplashScreen");

 private native static void _update(long splashPtr, int[] data, int x, int y, int width, int height, int scanlineStride);
 private native static boolean _isVisible(long splashPtr);
 private native static Rectangle _getBounds(long splashPtr);
 private native static long _getInstance();
 private native static void _close(long splashPtr);
 private native static String _getImageFileName(long splashPtr);
 private native static String _getImageJarName(long SplashPtr);
 private native static boolean _setImageData(long SplashPtr, byte[] data);
 private native static float _getScaleFactor(long SplashPtr);

}