package dndimagetest;

import java.awt.AWTException;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.application.Application;
import javafx.application.Platform;
import javafx.embed.swing.SwingFXUtils;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.image.Image;
import javafx.scene.image.ImageViewBuilder;
import javafx.scene.image.WritableImage;
import javafx.scene.input.Clipboard;
import javafx.scene.input.ClipboardContent;
import javafx.scene.input.DragEvent;
import javafx.scene.input.Dragboard;
import javafx.scene.input.MouseEvent;
import javafx.scene.input.TransferMode;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Pane;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
import javafx.stage.Window;
import javax.imageio.ImageIO;

public class DndImageTest extends Application {

    static {
        System.setProperty("java.awt.headless", "false");
    }
    final static String ID_SRC_IMAGE = "SrcImage";
    final static String ID_RECEIVED_IMAGE = "ReceivedImage";
    final static String ID_RECEIVED_IMAGE_2 = "ReceivedImage";
    Image CONTENT_IMAGE;
    Pane sourcePane = new VBox(getDefaultSpacing());
    Pane transferedContentPane = new VBox(getDefaultSpacing());
    Scene srcScene;
    Scene targetScene;
    Node srcNode;
    Node targetNode;
    Button btnScreenShot;

    @Override
    public void start(Stage stage) {

        CONTENT_IMAGE = new Image("file:JavaFX.png");

        sourcePane.getChildren().add(
                ImageViewBuilder.create()
                .image(CONTENT_IMAGE)
                .id(ID_SRC_IMAGE).build());

        //Set up source
        srcNode = new Button("Source");

        srcNode.setOnDragDetected(new EventHandler<MouseEvent>() {
            @Override
            public void handle(MouseEvent t) {
                Dragboard db = srcNode.startDragAndDrop(TransferMode.COPY);

                ClipboardContent content = new ClipboardContent();
                content.putImage(CONTENT_IMAGE);
                db.setContent(content);

                t.consume();
            }
        });

        srcNode.setOnDragDone(new EventHandler<DragEvent>() {
            @Override
            public void handle(DragEvent t) {
                System.out.println("Drag done");
            }
        });

        final Button target = new Button("Destination");

        target.setOnDragOver(new EventHandler<DragEvent>() {
            @Override
            public void handle(DragEvent t) {
                if (t.getGestureSource() != target
                        && t.getDragboard().hasImage()) {
                    t.acceptTransferModes(TransferMode.ANY);
                }

                t.consume();
            }
        });

        target.setOnDragDropped(new EventHandler<DragEvent>() {
            @Override
            public void handle(DragEvent t) {
                System.out.println("On drag dropped");
                boolean result = false;

                if (t.getGestureSource() == target) {
                    return;
                }

                Clipboard cb = t.getDragboard();

                if (cb.hasImage()) {
                    final Image image = cb.getImage();
                    System.out.println("Dropped image: " + image.toString());
                    transferedContentPane.getChildren().addAll(
                            ImageViewBuilder.create()
                            .image(image)
                            .id(ID_RECEIVED_IMAGE).build());

                    result = true;
                }

                t.setDropCompleted(result);
                t.consume();
            }
        });

        HBox root = new HBox(getDefaultSpacing());

        VBox vbLeft = new VBox(getDefaultSpacing());
        vbLeft.getChildren().addAll(srcNode, sourcePane);

        createAndLaunchTargetWnd();

        btnScreenShot = new Button("Screen shot");
        btnScreenShot.setOnAction(new EventHandler<ActionEvent>() {
            @Override
            public void handle(ActionEvent t) {
                takeSceneScreenshots();
            }
        });

        root.getChildren().addAll(vbLeft, btnScreenShot);
        srcScene = new Scene(root, getSceneWidth(), getSceneHeight());

        stage.setScene(srcScene);
        stage.setTitle(getTitle());
        stage.setX(10.0);
        stage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }

    private void createAndLaunchTargetWnd() {
        Stage stage = new Stage();

        final Pane contentPane = new VBox(getDefaultSpacing());

        targetNode = new Button("Destination");

        targetNode.setOnDragOver(new EventHandler<DragEvent>() {
            @Override
            public void handle(DragEvent t) {
                if (t.getGestureSource() != targetNode
                        && t.getDragboard().hasImage()) {
                    t.acceptTransferModes(TransferMode.ANY);
                }

                t.consume();
            }
        });

        targetNode.setOnDragDropped(new EventHandler<DragEvent>() {
            @Override
            public void handle(DragEvent t) {
                System.out.println("On drag dropped");
                boolean result = false;

                if (t.getGestureSource() == targetNode) {
                    return;
                }

                Clipboard cb = t.getDragboard();

                if (cb.hasImage()) {
                    final Image image = cb.getImage();
                    System.out.println("Dropped image: " + image.toString());
                    contentPane.getChildren().addAll(
                            ImageViewBuilder.create()
                            .image(image)
                            .id(ID_RECEIVED_IMAGE_2).build());
                    result = true;
                }

                t.setDropCompleted(result);
                t.consume();
            }
        });

        VBox vb = new VBox(getDefaultSpacing());
        vb.getChildren().addAll(targetNode, contentPane);

        HBox root = new HBox(getDefaultSpacing());
        root.getChildren().add(vb);

        targetScene = new Scene(root, getSceneWidth(), getSceneHeight());

        stage.setTitle(getTitle());
        stage.setScene(targetScene);
        stage.setX(getSceneWidth() + 50);
        stage.show();
    }

    private double getSceneWidth() {
        return 400.0;
    }

    private int getSceneHeight() {
        return 250;
    }

    private void compare(Image src, Image dst) {
        for (int i = 0; i < src.getWidth(); i++) {
            for (int j = 0; j < src.getHeight(); j++) {
                Color color1 = src.getPixelReader().getColor(i, j);
                Color color2 = dst.getPixelReader().getColor(i, j);

                if (!color1.equals(color2)) {
                    System.out.println("Pixel is different :"
                            + "(" + i + ";" + j + ")");
                    System.out.println("Expected = " + color1);
                    System.out.println("Actual = " + color2);
                }
            }
        }
    }

    private String getTitle() {
        return System.getProperty("java.runtime.version")
                + ";" + System.getProperty("javafx.runtime.version");
    }

    private void takeSceneScreenshots() {
        srcNode.setVisible(false);
        targetNode.setVisible(false);
        btnScreenShot.setVisible(false);

        WritableImage src = srcScene.snapshot(null);
        saveImg("SrcScene", src);

        WritableImage target = targetScene.snapshot(null);
        saveImg("TargetScene", target);

        compare(src, target);

        try {
            Robot rob = new Robot();

            Window wnd1 = srcScene.getWindow();
            Window wnd2 = targetScene.getWindow();

            BufferedImage capture1 = rob.createScreenCapture(
                    new Rectangle((int) wnd1.getX(), (int) wnd1.getY() + 50,
                    (int) wnd1.getWidth(), (int) wnd1.getHeight() - 50));

            File f = new File("img/AWT_Src.png");
            f.getParentFile().mkdirs();

            try {
                ImageIO.write(capture1, "png", f);
            } catch (IOException ex) {
                Logger.getLogger(DndImageTest.class.getName()).log(Level.SEVERE, null, ex);
                return;
            }
            
            BufferedImage capture2 = rob.createScreenCapture(
                                  new Rectangle((int) wnd2.getX(), (int) wnd2.getY() + 50,
                                  (int) wnd2.getWidth(), (int) wnd2.getHeight() - 50));

            f = new File("img/AWT_Target.png");

            try {
                ImageIO.write(capture2, "png", f);
            } catch (IOException ex) {
                Logger.getLogger(DndImageTest.class.getName()).log(Level.SEVERE, null, ex);
                return;
            }

            compare(SwingFXUtils.toFXImage(capture1, null), SwingFXUtils.toFXImage(capture2, null));
            
        } catch (AWTException ex) {
            Logger.getLogger(DndImageTest.class.getName()).log(Level.SEVERE, null, ex);
        }

        srcNode.setVisible(true);
        targetNode.setVisible(true);
        btnScreenShot.setVisible(true);
    }

    private void saveImg(String name, Image img) {
        File f = new File("img/" + name + ".png");
        f.getParentFile().mkdirs();

        try {
            ImageIO.write(SwingFXUtils.fromFXImage(img, null), "png", f);
        } catch (IOException ex) {
            Logger.getLogger(DndImageTest.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    private int getDefaultSpacing() {
        return 5;
    }
}