import java.awt.image.BufferedImage;
import javafx.application.Application;
import javafx.embed.swing.SwingFXUtils;
import javafx.scene.image.Image;
import javafx.scene.image.PixelFormat;
import javafx.scene.image.PixelReader;
import javafx.stage.Stage;

public class ReadImages extends Application {
    static boolean verbose;
    static int errors;

    @Override
    public void start(Stage stage) {
        // Not reached...
    }
    
    public static void test() {
        String imgnames[] = {
            "alpha.png",
            "opaque.gif",
            "opaque.jpg",
            "opaque.png",
            "trans.gif",
        };

        for (int i = 0; i < imgnames.length; i++) {
            String name = imgnames[i];
            Image img = new Image(name);
            boolean rgbrequired = (img.getPixelReader().getPixelFormat().getType() == PixelFormat.Type.BYTE_RGB);
            BufferedImage bimg = SwingFXUtils.fromFXImage(img, null);
            checkBimg(img, bimg);
            System.out.println(name+" type = "+img.getPixelReader().getPixelFormat());
            System.out.println(name+" bimg type = "+bimg.getType());
            System.out.println(name+" reuses own bimg = "+reusesBimg(img, bimg, true));
            System.out.println(name+" reuses rgb bimg = "+reusesBimg(img, BufferedImage.TYPE_INT_RGB, rgbrequired));
            System.out.println(name+" reuses argb bimg = "+reusesBimg(img, BufferedImage.TYPE_INT_ARGB, true));
            System.out.println(name+" reuses argb pre bimg = "+reusesBimg(img, BufferedImage.TYPE_INT_ARGB_PRE, true));
            System.out.println();
        }

        if (errors == 0) {
            System.out.println("No errors encountered");
        } else {
            System.out.flush();
            throw new RuntimeException(errors+" errors encountered");
        }

        System.exit(0);
    }

    static boolean reusesBimg(Image img, int type, boolean required) {
        int iw = (int) img.getWidth();
        int ih = (int) img.getHeight();
        BufferedImage bimg = new BufferedImage(iw, ih, type);
        return reusesBimg(img, bimg, required);
    }

    static boolean reusesBimg(Image img, BufferedImage bimg, boolean required) {
        BufferedImage ret = SwingFXUtils.fromFXImage(img, bimg);
        checkBimg(img, ret);
        if (bimg == ret) {
            return true;
        } else {
            if (required) errors++;
            return false;
        }
    }

    static void checkBimg(Image img, BufferedImage bimg) {
        PixelReader pr = img.getPixelReader();
        int iw = (int) img.getWidth();
        int ih = (int) img.getHeight();
        for (int y = 0; y < ih; y++) {
            for (int x = 0; x < iw; x++) {
                int imgargb = pr.getArgb(x, y);
                int bimgargb = bimg.getRGB(x, y);
                if (imgargb != bimgargb) {
                    System.out.println(">>>> wrong color in bimg: "+hex(bimgargb)+
                                       " at "+x+", "+y+
                                       " should be: "+hex(imgargb));
                    errors++;
                } else if (verbose) {
                    System.out.println(hex(imgargb)+" => "+hex(bimgargb));
                }
            }
        }
    }

    static String hex(int i) {
        return String.format("0x%08x", i);
    }

    public static void main(String argv[]) {
        verbose = (argv.length > 0);
        test();
    }
}