source: josm/trunk/src/org/openstreetmap/josm/actions/MoveAction.java@ 627

//License: GPL. Copyright 2007 by Immanuel Scholz and others
package org.openstreetmap.josm.actions;

import static org.openstreetmap.josm.tools.I18n.tr;

import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.util.Collection;

import javax.swing.JOptionPane;

import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.command.Command;
import org.openstreetmap.josm.command.MoveCommand;
import org.openstreetmap.josm.data.coor.EastNorth;
import org.openstreetmap.josm.data.osm.Node;
import org.openstreetmap.josm.data.osm.OsmPrimitive;
import org.openstreetmap.josm.data.osm.visitor.AllNodesVisitor;

/**
 * Moves the selection
 * 
 * @author Frederik Ramm
 */
public class MoveAction extends JosmAction {

        public enum Direction { UP, LEFT, RIGHT, DOWN }
        private Direction myDirection;
        
        public MoveAction(Direction dir) {
                super(tr("Move"), null, tr("Moves Objects"), 
                (dir == Direction.UP) ? KeyEvent.VK_UP : 
                (dir == Direction.DOWN) ? KeyEvent.VK_DOWN :
                (dir == Direction.LEFT) ? KeyEvent.VK_LEFT :
                KeyEvent.VK_RIGHT, 0, true);
                myDirection = dir;
        }

        public void actionPerformed(ActionEvent event) {
                
                // find out how many "real" units the objects have to be moved in order to
                // achive an 1-pixel movement
                
                EastNorth en1 = Main.map.mapView.getEastNorth(100, 100);
                EastNorth en2 = Main.map.mapView.getEastNorth(101, 101);
                
                double distx = en2.east() - en1.east();
                double disty = en2.north() - en1.north();
                
                switch (myDirection) {
                case UP: 
                        distx = 0;
                        disty = -disty;
                        break;
                case DOWN:
                        distx = 0;
                        break;
                case LEFT:
                        disty = 0;
                        distx = -distx;
                default:
                        disty = 0;
                }
                
                Collection<OsmPrimitive> selection = Main.ds.getSelected();
                Collection<Node> affectedNodes = AllNodesVisitor.getAllNodes(selection);
                
                Command c = !Main.main.undoRedo.commands.isEmpty()
                ? Main.main.undoRedo.commands.getLast() : null;

                if (c instanceof MoveCommand && affectedNodes.equals(((MoveCommand)c).objects))
                        ((MoveCommand)c).moveAgain(distx, disty);
                else
                        Main.main.undoRedo.add(
                                        c = new MoveCommand(selection, distx, disty));

                for (Node n : affectedNodes) {
                        if (n.coor.isOutSideWorld()) {
                                // Revert move
                                ((MoveCommand) c).moveAgain(-distx, -disty);
                                JOptionPane.showMessageDialog(Main.parent,
                                                tr("Cannot move objects outside of the world."));
                                return;
                        }
                }

                Main.map.mapView.repaint();
        }
}