package demo.view.advanced;

import demo.view.DemoBase;
import y.base.Node;
import y.view.HitInfo;

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.Point;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.StringSelection;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.dnd.DnDConstants;
import java.awt.dnd.DragGestureEvent;
import java.awt.dnd.DragGestureListener;
import java.awt.dnd.DragSource;
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.io.IOException;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.tree.TreePath;

public class DragNamesDemo extends DemoBase {
  public DragNamesDemo() {
    //JTree with names
    final JTree tree = new JTree();
    tree.setDragEnabled(false);
    contentPane.add(new JScrollPane(tree), BorderLayout.WEST);

    //Drag event on source site:
    final DragSource dragSource = new DragSource();
    dragSource.createDefaultDragGestureRecognizer(
        tree,
        DnDConstants.ACTION_COPY,
        //Listener for drag gesture
        new DragGestureListener() {
          public void dragGestureRecognized(final DragGestureEvent event) {
            final Point p = event.getDragOrigin();
            final TreePath path = tree.getClosestPathForLocation(p.x, p.y);
            if (path != null) {
              //Dedermine the name ( = name of the component), which should be drag&droped to a node
              final Object o = path.getLastPathComponent();
              dragSource.startDrag(
                  event,
                  DragSource.DefaultCopyDrop,
                  //The name of the source = text for node-label
                  new StringSelection(o.toString()),
                  null);
            }
          }
        });

    //Drop event on target site:
    new DropTarget(view, new DropTargetListener() {
      public void dragEnter(final DropTargetDragEvent dtde) {
      }

      public void dragOver(final DropTargetDragEvent dtde) {
      }

      public void dropActionChanged(final DropTargetDragEvent dtde) {
      }

      //On drop event (mouse released)
      public void drop(final DropTargetDropEvent dtde) {
        final Point p = dtde.getLocation();
        //Look, where the drop hit
        final HitInfo hit = new HitInfo(view, view.toWorldCoordX(p.x), view.toWorldCoordY(p.y), true, HitInfo.NODE);

        if (hit.hasHitNodes()) {
          //A node was hit
          final Node node = hit.getHitNode();
          final Transferable t = dtde.getTransferable();
          try {
            //Adapt label-text for node of interest
            final String text = (String) t.getTransferData(DataFlavor.stringFlavor);
            view.getGraph2D().getRealizer(node).setLabelText(text);
            view.updateView();
            dtde.acceptDrop(DnDConstants.ACTION_COPY);
          } catch (UnsupportedFlavorException e) {
            dtde.rejectDrop();
          } catch (IOException e) {
            dtde.rejectDrop();
          }
        } else {
          dtde.rejectDrop();
        }
      }

      public void dragExit(final DropTargetEvent dte) {
      }
    });
  }

  public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable() {
      public void run() {
        initLnF();
        (new DragNamesDemo()).start();
      }
    });
  }
}