/*
 * Copyright (c) 2013, 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.
 *
 * 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.
 */

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import java.io.File;
import java.lang.reflect.Method;
import java.net.URL;
import javax.imageio.ImageIO;
import sun.awt.OSInfo;
import sun.awt.SunHints;
import com.sun.awt.MultiResolutionImage;
import java.awt.geom.AffineTransform;
import java.awt.image.ImageObserver;
import java.util.Arrays;
import java.util.List;

/**
 * @test
 * @bug 8011059
 * @author Alexander Scherbatiy
 * @summary [macosx] Make JDK demos look perfect on retina displays
 * @run main MultiResolutionImageTest
 */
public class MultiResolutionImageTest {

    private static final int WIDTH = 300;
    private static final int HEIGHT = 200;
    private static final Color COLOR_1X = Color.GREEN;
    private static final Color COLOR_2X = Color.BLUE;
    private static final String IMAGE_NAME_1X = "image.png";
    private static final String IMAGE_NAME_2X = "image@2x.png";

    public static void main(String[] args) throws Exception {
        testCustomMultiResolutionImage();

        if (OSInfo.getOSType() == OSInfo.OSType.MACOSX) {
            testToolkitMultiResolutionImage();
            testImageNameTo2xParsing();
        }
    }

    public static void testCustomMultiResolutionImage() {
        testCustomMultiResolutionImage(false);
        testCustomMultiResolutionImage(true);
    }

    public static void testCustomMultiResolutionImage(boolean enableImageScaling) {

        Image image = new MultiResolutionBufferedImage();

        // Same image size
        BufferedImage bufferedImage = new BufferedImage(WIDTH, HEIGHT,
                BufferedImage.TYPE_INT_RGB);
        Graphics2D g2d = (Graphics2D) bufferedImage.getGraphics();
        setImageScalingHint(g2d, enableImageScaling);
        g2d.drawImage(image, 0, 0, null);
        checkColor(bufferedImage.getRGB(3 * WIDTH / 4, 3 * HEIGHT / 4), false);

        // Twice image size
        bufferedImage = new BufferedImage(2 * WIDTH, 2 * HEIGHT,
                BufferedImage.TYPE_INT_RGB);
        g2d = (Graphics2D) bufferedImage.getGraphics();
        setImageScalingHint(g2d, enableImageScaling);
        g2d.drawImage(image, 0, 0, 2 * WIDTH, 2 * HEIGHT, 0, 0, WIDTH, HEIGHT, null);
        checkColor(bufferedImage.getRGB(3 * WIDTH / 2, 3 * HEIGHT / 2), enableImageScaling);

        // Scale 2x
        bufferedImage = new BufferedImage(2 * WIDTH, 2 * HEIGHT, BufferedImage.TYPE_INT_RGB);
        g2d = (Graphics2D) bufferedImage.getGraphics();
        setImageScalingHint(g2d, enableImageScaling);
        g2d.scale(2, 2);
        g2d.drawImage(image, 0, 0, WIDTH, HEIGHT, null);
        checkColor(bufferedImage.getRGB(3 * WIDTH / 2, 3 * HEIGHT / 2), enableImageScaling);

        // Rotate
        bufferedImage = new BufferedImage(WIDTH, HEIGHT,
                BufferedImage.TYPE_INT_RGB);
        g2d = (Graphics2D) bufferedImage.getGraphics();
        setImageScalingHint(g2d, enableImageScaling);
        g2d.drawImage(image, 0, 0, null);
        g2d.rotate(Math.PI / 4);
        checkColor(bufferedImage.getRGB(3 * WIDTH / 4, 3 * HEIGHT / 4), false);

        // Scale 2x and Rotate
        bufferedImage = new BufferedImage(2 * WIDTH, 2 * HEIGHT, BufferedImage.TYPE_INT_RGB);
        g2d = (Graphics2D) bufferedImage.getGraphics();
        setImageScalingHint(g2d, enableImageScaling);
        g2d.scale(-2, 2);
        g2d.rotate(-Math.PI / 10);
        g2d.drawImage(image, -WIDTH, 0, WIDTH, HEIGHT, null);
        checkColor(bufferedImage.getRGB(3 * WIDTH / 2, 3 * HEIGHT / 2), enableImageScaling);

        // General Transform
        bufferedImage = new BufferedImage(2 * WIDTH, 2 * HEIGHT, BufferedImage.TYPE_INT_RGB);
        g2d = (Graphics2D) bufferedImage.getGraphics();
        setImageScalingHint(g2d, enableImageScaling);
        float delta = 0.05f;
        float cos = 1 - delta * delta / 2;
        float sin = 1 + delta;
        AffineTransform transform = new AffineTransform(2 * cos, 0.1, 0.3, -2 * sin, 10, -5);
        g2d.setTransform(transform);
        g2d.drawImage(image, 0, -HEIGHT, WIDTH, HEIGHT, null);
        checkColor(bufferedImage.getRGB(3 * WIDTH / 2, 3 * HEIGHT / 2), enableImageScaling);

        int D = 10;
        // From Source to small Destination region
        bufferedImage = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
        g2d = (Graphics2D) bufferedImage.getGraphics();
        setImageScalingHint(g2d, enableImageScaling);
        g2d.drawImage(image, WIDTH / 2, HEIGHT / 2, WIDTH - D, HEIGHT - D,
                D, D, WIDTH - D, HEIGHT - D, null);
        checkColor(bufferedImage.getRGB(3 * WIDTH / 4, 3 * HEIGHT / 4), false);

        // From Source to large Destination region
        bufferedImage = new BufferedImage(2 * WIDTH, 2 * HEIGHT, BufferedImage.TYPE_INT_RGB);
        g2d = (Graphics2D) bufferedImage.getGraphics();
        setImageScalingHint(g2d, enableImageScaling);
        g2d.drawImage(image, D, D, 2 * WIDTH - D, 2 * HEIGHT - D,
                WIDTH / 2, HEIGHT / 2, WIDTH - D, HEIGHT - D, null);
        checkColor(bufferedImage.getRGB(3 * WIDTH / 2, 3 * HEIGHT / 2), enableImageScaling);
    }

    static class MultiResolutionBufferedImage extends BufferedImage
            implements MultiResolutionImage {

        Image highResolutionImage;

        public MultiResolutionBufferedImage() {
            super(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
            highResolutionImage = new BufferedImage(
                    2 * WIDTH, 2 * HEIGHT, BufferedImage.TYPE_INT_RGB);
            draw(getGraphics(), 1);
            draw(highResolutionImage.getGraphics(), 2);
        }

        void draw(Graphics graphics, float resolution) {
            Graphics2D g2 = (Graphics2D) graphics;
            g2.scale(resolution, resolution);
            g2.setColor((resolution == 1) ? COLOR_1X : COLOR_2X);
            g2.fillRect(0, 0, WIDTH, HEIGHT);
        }

        @Override
        public Image getResolutionVariant(int width, int height) {
            return ((width <= getWidth() && height <= getHeight()))
                    ? this : highResolutionImage;
        }

        @Override
        public List<Image> getResolutionVariants() {
            return Arrays.asList(this, highResolutionImage);
        }
    }

    static void testToolkitMultiResolutionImage() throws Exception {

        generateImage(1);
        generateImage(2);

        File imageFile = new File(IMAGE_NAME_1X);
        Image image = Toolkit.getDefaultToolkit().getImage(imageFile.getAbsolutePath());
        testToolkitMultiResolutionImage(image, false);
        testToolkitMultiResolutionImage(image, true);

        image = Toolkit.getDefaultToolkit().getImage(imageFile.toURI().toURL());
        testToolkitMultiResolutionImage(image, false);
        testToolkitMultiResolutionImage(image, true);
    }

    static void testToolkitMultiResolutionImage(Image image, boolean enableImageScaling)
            throws Exception {

        ImageObserver observer = new PreloadedImageObserver();

        if (image.getWidth(observer) <= 0) {
            throw new RuntimeException("Image should be already preloaded!");
        }

        final BufferedImage bufferedImage1x = new BufferedImage(WIDTH, HEIGHT,
                BufferedImage.TYPE_INT_RGB);
        Graphics2D g1x = (Graphics2D) bufferedImage1x.getGraphics();
        setImageScalingHint(g1x, false);
        g1x.drawImage(image, 0, 0, null);
        checkColor(bufferedImage1x.getRGB(3 * WIDTH / 4, 3 * HEIGHT / 4), false);

        Image resolutionVariant = ((MultiResolutionImage) image).
                getResolutionVariant(2 * WIDTH, 2 * HEIGHT);

        if (resolutionVariant == null) {
            throw new RuntimeException("Resolution variant is null");
        }

        if (resolutionVariant.getHeight(observer) <= 0) {
            throw new RuntimeException("Image should be already preloaded!");
        }

        final BufferedImage bufferedImage2x = new BufferedImage(2 * WIDTH,
                2 * HEIGHT, BufferedImage.TYPE_INT_RGB);
        Graphics2D g2x = (Graphics2D) bufferedImage2x.getGraphics();
        setImageScalingHint(g2x, enableImageScaling);
        g2x.drawImage(image, 0, 0, 2 * WIDTH, 2 * HEIGHT, 0, 0, WIDTH, HEIGHT, null);
        checkColor(bufferedImage2x.getRGB(3 * WIDTH / 2, 3 * HEIGHT / 2), enableImageScaling);

        List<Image> resolutionVariants = ((MultiResolutionImage) image).
                getResolutionVariants();

        if (resolutionVariants.size() != 2) {
            throw new RuntimeException("Wrong number of resolution variants");
        }

        Image image1x = resolutionVariants.get(0);
        Image image2x = resolutionVariants.get(1);

        if (image1x.getWidth(observer) * 2 != image2x.getWidth(observer)
                || image1x.getHeight(observer) * 2 != image2x.getHeight(observer)) {
            throw new RuntimeException("Wrong resolution variant size");
        }

    }

    static void setImageScalingHint(Graphics2D g2d, boolean enableImageScaling) {
        g2d.setRenderingHint(SunHints.KEY_RESOLUTION_VARIANT, enableImageScaling
                ? SunHints.VALUE_RESOLUTION_VARIANT_ON
                : SunHints.VALUE_RESOLUTION_VARIANT_OFF);
    }

    static void checkColor(int rgb, boolean isImageScaled) {

        if (!isImageScaled && COLOR_1X.getRGB() != rgb) {
            throw new RuntimeException("Wrong 1x color: " + new Color(rgb));
        }

        if (isImageScaled && COLOR_2X.getRGB() != rgb) {
            throw new RuntimeException("Wrong 2x color" + new Color(rgb));
        }
    }

    static void generateImage(int scale) throws Exception {
        BufferedImage image = new BufferedImage(scale * WIDTH, scale * HEIGHT,
                BufferedImage.TYPE_INT_RGB);
        Graphics g = image.getGraphics();
        g.setColor(scale == 1 ? COLOR_1X : COLOR_2X);
        g.fillRect(0, 0, scale * WIDTH, scale * HEIGHT);
        File file = new File(scale == 1 ? IMAGE_NAME_1X : IMAGE_NAME_2X);
        ImageIO.write(image, "png", file);
    }

    static void testImageNameTo2xParsing() throws Exception {

        for (String[] testNames : TEST_FILE_NAMES) {
            String testName = testNames[0];
            String goldenName = testNames[1];
            String resultName = getTestScaledImageName(testName);

            if (!isValidPath(testName) && resultName == null) {
                continue;
            }

            if (goldenName.equals(resultName)) {
                continue;
            }

            throw new RuntimeException("Test name " + testName
                    + ", result name: " + resultName);
        }

        for (URL[] testURLs : TEST_URLS) {
            URL testURL = testURLs[0];
            URL goldenURL = testURLs[1];
            URL resultURL = getTestScaledImageURL(testURL);

            if (!isValidPath(testURL.getPath()) && resultURL == null) {
                continue;
            }

            if (goldenURL.equals(resultURL)) {
                continue;
            }

            throw new RuntimeException("Test url: " + testURL
                    + ", result url: " + resultURL);
        }

    }

    static URL getTestScaledImageURL(URL url) throws Exception {
        Method method = getScalableImageMethod("getScaledImageURL", URL.class);
        return (URL) method.invoke(null, url);
    }

    static String getTestScaledImageName(String name) throws Exception {
        Method method = getScalableImageMethod("getScaledImageName", String.class);
        return (String) method.invoke(null, name);
    }

    private static boolean isValidPath(String path) {
        return !path.isEmpty() && !path.endsWith("/") && !path.endsWith(".");
    }

    private static Method getScalableImageMethod(String name,
            Class... parameterTypes) throws Exception {
        Toolkit toolkit = Toolkit.getDefaultToolkit();
        Method method = toolkit.getClass().getDeclaredMethod(name, parameterTypes);
        method.setAccessible(true);
        return method;
    }
    private static final String[][] TEST_FILE_NAMES;
    private static final URL[][] TEST_URLS;

    static {
        TEST_FILE_NAMES = new String[][]{
            {"", null},
            {".", null},
            {"..", null},
            {"/", null},
            {"/.", null},
            {"dir/", null},
            {"dir/.", null},
            {"image", "image@2x"},
            {"image.ext", "image@2x.ext"},
            {"image.aaa.ext", "image.aaa@2x.ext"},
            {"dir/image", "dir/image@2x"},
            {"dir/image.ext", "dir/image@2x.ext"},
            {"dir/image.aaa.ext", "dir/image.aaa@2x.ext"},
            {"dir/aaa.bbb/image", "dir/aaa.bbb/image@2x"},
            {"dir/aaa.bbb/image.ext", "dir/aaa.bbb/image@2x.ext"},
            {"dir/aaa.bbb/image.ccc.ext", "dir/aaa.bbb/image.ccc@2x.ext"},
            {"/dir/image", "/dir/image@2x"},
            {"/dir/image.ext", "/dir/image@2x.ext"},
            {"/dir/image.aaa.ext", "/dir/image.aaa@2x.ext"},
            {"/dir/aaa.bbb/image", "/dir/aaa.bbb/image@2x"},
            {"/dir/aaa.bbb/image.ext", "/dir/aaa.bbb/image@2x.ext"},
            {"/dir/aaa.bbb/image.ccc.ext", "/dir/aaa.bbb/image.ccc@2x.ext"}
        };
        try {
            TEST_URLS = new URL[][]{
                // file
                {new URL("file:/aaa"), new URL("file:/aaa@2x")},
                {new URL("file:/aaa.ext"), new URL("file:/aaa@2x.ext")},
                {new URL("file:/aaa.bbb.ext"), new URL("file:/aaa.bbb@2x.ext")},
                {new URL("file:/ccc/aaa.bbb.ext"),
                    new URL("file:/ccc/aaa.bbb@2x.ext")},
                {new URL("file:/ccc.ddd/aaa.bbb.ext"),
                    new URL("file:/ccc.ddd/aaa.bbb@2x.ext")},
                {new URL("file:///~/image"), new URL("file:///~/image@2x")},
                {new URL("file:///~/image.ext"),
                    new URL("file:///~/image@2x.ext")},
                // http
                {new URL("http://www.test.com"), null},
                {new URL("http://www.test.com/"), null},
                {new URL("http://www.test.com///"), null},
                {new URL("http://www.test.com/image"),
                    new URL("http://www.test.com/image@2x")},
                {new URL("http://www.test.com/image.ext"),
                    new URL("http://www.test.com/image@2x.ext")},
                {new URL("http://www.test.com/dir/image"),
                    new URL("http://www.test.com/dir/image@2x")},
                {new URL("http://www.test.com:80/dir/image.aaa.ext"),
                    new URL("http://www.test.com:80/dir/image.aaa@2x.ext")},
                {new URL("http://www.test.com:8080/dir/image.aaa.ext"),
                    new URL("http://www.test.com:8080/dir/image.aaa@2x.ext")},
                // jar
                {new URL("jar:file:/dir/Java2D.jar!/image"),
                    new URL("jar:file:/dir/Java2D.jar!/image@2x")},
                {new URL("jar:file:/dir/Java2D.jar!/image.aaa.ext"),
                    new URL("jar:file:/dir/Java2D.jar!/image.aaa@2x.ext")},
                {new URL("jar:file:/dir/Java2D.jar!/images/image"),
                    new URL("jar:file:/dir/Java2D.jar!/images/image@2x")},
                {new URL("jar:file:/dir/Java2D.jar!/images/image.ext"),
                    new URL("jar:file:/dir/Java2D.jar!/images/image@2x.ext")},
                {new URL("jar:file:/aaa.bbb/Java2D.jar!/images/image.ext"),
                    new URL("jar:file:/aaa.bbb/Java2D.jar!/images/image@2x.ext")},
                {new URL("jar:file:/dir/Java2D.jar!/aaa.bbb/image.ext"),
                    new URL("jar:file:/dir/Java2D.jar!/aaa.bbb/image@2x.ext")},};
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    static class PreloadedImageObserver implements ImageObserver {

        @Override
        public boolean imageUpdate(Image img, int infoflags, int x, int y, int width, int height) {
            throw new RuntimeException("Image should be already preloaded");
        }
    }
}