import java.awt.Canvas;
import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.dnd.DropTarget;
import java.awt.dnd.DropTargetDragEvent;
import java.awt.dnd.DropTargetDropEvent;
import java.awt.dnd.DropTargetEvent;
import java.awt.dnd.DropTargetListener;
import java.awt.geom.Rectangle2D;

import javax.swing.SwingUtilities;

import org.eclipse.swt.SWT;
import org.eclipse.swt.awt.SWT_AWT;
import org.eclipse.swt.dnd.DND;
import org.eclipse.swt.dnd.DragSource;
import org.eclipse.swt.dnd.DragSourceEffect;
import org.eclipse.swt.dnd.DragSourceEvent;
import org.eclipse.swt.dnd.DragSourceListener;
import org.eclipse.swt.dnd.TextTransfer;
import org.eclipse.swt.dnd.Transfer;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;

public class MacDNDTestSnippet {

	public static void main(String[] args) {

		new MacDNDTestSnippet().run();

	}

	private void run() {

		Display display = new Display();
		Shell shell = new Shell(display);

		shell.setLayout(new GridLayout());

		Composite composite = new Composite(shell, SWT.NONE);
		composite.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));

		composite.setLayout(new GridLayout());

		createHeaderPanel(composite, new GridData(SWT.FILL, SWT.FILL, true,
				false)); // to reproduce menu and toolbar space

		createDndPanels(composite, new GridData(SWT.FILL, SWT.FILL, true, true)); // to
																					// reproduce
																					// drop
																					// target
																					// panel
																					// and
																					// drag
																					// source

		setLocation(shell);
		shell.open();
		while (!shell.isDisposed()) {
			if (!display.readAndDispatch())
				display.sleep();
		}
		display.dispose();

	}

	private void setLocation(Shell shell) {
		Rectangle monitorSize = shell.getMonitor().getClientArea();
		int width = 2 * monitorSize.width / 3;
		int height = 2 * monitorSize.height / 3;
		shell.setBounds((monitorSize.width + width) / 2,
				(monitorSize.height + height) / 2, width, height);
	}

	private void createHeaderPanel(Composite parent, Object layoutData) {

		Text header = new Text(parent, SWT.READ_ONLY | SWT.MULTI);
		header.setText("Menu 1 | Menu 2 | Menu 3\nToolbar buttons...");
		header.setLayoutData(layoutData);

	}

	private void createDndPanels(Composite parent, Object layoutData) {

		Composite composite = new Composite(parent, SWT.NONE);
		composite.setLayoutData(layoutData);

		GridLayout gridLayout = new GridLayout();
		gridLayout.marginWidth = gridLayout.marginWidth = 0;
		composite.setLayout(gridLayout);

		DropZonePanel panel = createAWTComp(composite, new GridData(SWT.FILL,
				SWT.FILL, true, true));
		installDrop(panel);

		Label label = createSWTComp(composite, new GridData(SWT.FILL, SWT.FILL,
				true, false));
		installDrag(label, panel);

	}

	private void installDrag(Label label, final DropZonePanel panel) {
		new DragSourceEffect(label) {
			@Override
			public void dragStart(DragSourceEvent event) {
				System.out.println("Drag start on SWT");
				super.dragStart(event);
			}

			@Override
			public void dragSetData(DragSourceEvent event) {
				System.out.println("Drag setData on SWT");
				super.dragSetData(event);
			}

			@Override
			public void dragFinished(DragSourceEvent event) {
				System.out.println("Drag finished");
				super.dragFinished(event);
			}
		};
		final DragSource dragSource = new DragSource(label, DND.DROP_COPY
				| DND.DROP_MOVE);
		Transfer[] dragTranferTypes = new Transfer[] { TextTransfer
				.getInstance() };
		dragSource.setTransfer(dragTranferTypes);
		dragSource.addDragListener(new DragSourceListener() {

			@Override
			public void dragStart(DragSourceEvent event) {
				System.out.println("Drag start on SWT Listener");
				panel.init();
			}

			@Override
			public void dragSetData(DragSourceEvent event) {
				System.out.println("Drag set data on SWT Listener");
				event.data = "test";
				event.doit = true;
			}

			@Override
			public void dragFinished(DragSourceEvent event) {
				System.out.println("Drag finished on SWT Listener");

			}
		});
	}

	private void installDrop(final DropZonePanel panel) {
		DropTarget dropTarget = new DropTarget(panel, new DropTargetListener() {

			@Override
			public void dropActionChanged(DropTargetDragEvent dtde) {
				System.out.println("drop Action changed on AWT");
			}

			@Override
			public void drop(DropTargetDropEvent dtde) {
				System.out.println("drop on AWT");
				dtde.rejectDrop();
			}

			@Override
			public void dragOver(DropTargetDragEvent dtde) {
				System.out.println("drag over on AWT - Relative to component Mouse location / Target bounds: " + dtde.getLocation() + " / " + dtde.getDropTargetContext().getComponent().getBounds());
				System.out.println("drag over on AWT - Relative to screen Mouse location / Target bounds: " + getRTSLocation(dtde) + " / " + getRTSBounds(dtde));
				System.out.println("drag over on AWT - Relative to screen Frame bounds: " + getFrameBounds(dtde));
				panel.update(dtde.getLocation());
			}

			private java.awt.Rectangle getFrameBounds(DropTargetDragEvent dtde) {
				Component component = dtde.getDropTargetContext().getComponent();
				Container frame = SwingUtilities.getAncestorOfClass(Frame.class, component);
				java.awt.Rectangle bounds = frame.getBounds();
				bounds.setLocation(frame.getLocationOnScreen());
				return bounds;
			}

			private java.awt.Rectangle getRTSBounds(DropTargetDragEvent dtde) {
				Component component = dtde.getDropTargetContext().getComponent();
				java.awt.Rectangle bounds = component.getBounds();
				bounds.setLocation(component.getLocationOnScreen());
				return bounds;
			}
			
			private Point getRTSLocation(DropTargetDragEvent dtde) {
				Point p = dtde.getLocation();
				SwingUtilities.convertPointToScreen(p, dtde.getDropTargetContext().getComponent());
				return p;
			}

			@Override
			public void dragExit(DropTargetEvent dte) {
				System.out.println("drag exit on AWT - Target bounds: " + dte.getDropTargetContext().getComponent().getBounds()  );
			}

			@Override
			public void dragEnter(DropTargetDragEvent dtde) {
				System.out.println("drag enter on AWT - Mouse location: " + dtde.getLocation() + " - Target bounds: " + dtde.getDropTargetContext().getComponent().getBounds()  );
			}
		});
		panel.setDropTarget(dropTarget);
	}

	private DropZonePanel createAWTComp(final Composite parent,
			Object layoutData) {

		final Composite composite = new Composite(parent, SWT.EMBEDDED
				| SWT.NO_BACKGROUND);
		composite.setLayoutData(layoutData);

		final DropZonePanel panel = new DropZonePanel();
		panel.setBackground(Color.GREEN);

		SWT_AWT.embeddedFrameClass = "sun.lwawt.macosx.CViewEmbeddedFrame";
		final Frame frame = SWT_AWT.new_Frame(composite);

		frame.add(panel);

		return panel;

	}

	private Label createSWTComp(Composite parent, Object layoutData) {
		Label label = new Label(parent, SWT.NONE);
		label.setLayoutData(layoutData);
		label.setText("Some text... (Drag me to green area)");
		return label;
	}

	private static class DropZonePanel extends Canvas {
		
		private static final long serialVersionUID = 1L;
		
		private java.awt.Rectangle rectangle;

		public DropZonePanel() {
		}

		public void init() {
			if (rectangle != null) {
				rectangle = null;
				repaint();
			}
		}

		public void update(Point location) {
			if (rectangle == null) {
				rectangle = new java.awt.Rectangle(location.x, location.y, 1, 1);
			} else {
				Rectangle2D.union(rectangle, new java.awt.Rectangle(location.x,
						location.y, 1, 1), rectangle);
			}
			repaint();
		}

		@Override
		public void paint(Graphics g) {
			super.paint(g);
			if (rectangle != null) {
				g.setColor(Color.RED);
				g.fillRect(rectangle.x, rectangle.y, rectangle.width,
						rectangle.height);
			}
		}

	}

}