001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.actions.mapmode;
003
004import static org.openstreetmap.josm.gui.help.HelpUtil.ht;
005import static org.openstreetmap.josm.tools.I18n.tr;
006import static org.openstreetmap.josm.tools.I18n.trn;
007
008import java.awt.AWTEvent;
009import java.awt.Cursor;
010import java.awt.Point;
011import java.awt.Rectangle;
012import java.awt.Toolkit;
013import java.awt.event.AWTEventListener;
014import java.awt.event.ActionEvent;
015import java.awt.event.ActionListener;
016import java.awt.event.InputEvent;
017import java.awt.event.KeyEvent;
018import java.awt.event.MouseEvent;
019import java.awt.geom.Point2D;
020import java.util.Collection;
021import java.util.Collections;
022import java.util.HashSet;
023import java.util.Iterator;
024import java.util.LinkedList;
025import java.util.Set;
026
027import javax.swing.JOptionPane;
028
029import org.openstreetmap.josm.Main;
030import org.openstreetmap.josm.actions.MergeNodesAction;
031import org.openstreetmap.josm.command.AddCommand;
032import org.openstreetmap.josm.command.ChangeCommand;
033import org.openstreetmap.josm.command.Command;
034import org.openstreetmap.josm.command.MoveCommand;
035import org.openstreetmap.josm.command.RotateCommand;
036import org.openstreetmap.josm.command.ScaleCommand;
037import org.openstreetmap.josm.command.SequenceCommand;
038import org.openstreetmap.josm.data.coor.EastNorth;
039import org.openstreetmap.josm.data.coor.LatLon;
040import org.openstreetmap.josm.data.osm.DataSet;
041import org.openstreetmap.josm.data.osm.Node;
042import org.openstreetmap.josm.data.osm.OsmPrimitive;
043import org.openstreetmap.josm.data.osm.Way;
044import org.openstreetmap.josm.data.osm.WaySegment;
045import org.openstreetmap.josm.data.osm.visitor.AllNodesVisitor;
046import org.openstreetmap.josm.data.osm.visitor.paint.WireframeMapRenderer;
047import org.openstreetmap.josm.gui.ExtendedDialog;
048import org.openstreetmap.josm.gui.MapFrame;
049import org.openstreetmap.josm.gui.MapView;
050import org.openstreetmap.josm.gui.NavigatableComponent;
051import org.openstreetmap.josm.gui.SelectionManager;
052import org.openstreetmap.josm.gui.SelectionManager.SelectionEnded;
053import org.openstreetmap.josm.gui.layer.Layer;
054import org.openstreetmap.josm.gui.layer.OsmDataLayer;
055import org.openstreetmap.josm.gui.util.GuiHelper;
056import org.openstreetmap.josm.tools.ImageProvider;
057import org.openstreetmap.josm.tools.Pair;
058import org.openstreetmap.josm.tools.PlatformHookOsx;
059import org.openstreetmap.josm.tools.Shortcut;
060
061/**
062 * Move is an action that can move all kind of OsmPrimitives (except keys for now).
063 *
064 * If an selected object is under the mouse when dragging, move all selected objects.
065 * If an unselected object is under the mouse when dragging, it becomes selected
066 * and will be moved.
067 * If no object is under the mouse, move all selected objects (if any)
068 *
069 * @author imi
070 */
071public class SelectAction extends MapMode implements AWTEventListener, SelectionEnded {
072    // "select" means the selection rectangle and "move" means either dragging
073    // or select if no mouse movement occurs (i.e. just clicking)
074    enum Mode { move, rotate, scale, select }
075
076    // contains all possible cases the cursor can be in the SelectAction
077    static private enum SelectActionCursor {
078        rect("normal", "selection"),
079        rect_add("normal", "select_add"),
080        rect_rm("normal", "select_remove"),
081        way("normal", "select_way"),
082        way_add("normal", "select_way_add"),
083        way_rm("normal", "select_way_remove"),
084        node("normal", "select_node"),
085        node_add("normal", "select_node_add"),
086        node_rm("normal", "select_node_remove"),
087        virtual_node("normal", "addnode"),
088        scale("scale", null),
089        rotate("rotate", null),
090        merge("crosshair", null),
091        lasso("normal", "rope"),
092        merge_to_node("crosshair", "joinnode"),
093        move(Cursor.MOVE_CURSOR);
094
095        private final Cursor c;
096        private SelectActionCursor(String main, String sub) {
097            c = ImageProvider.getCursor(main, sub);
098        }
099        private SelectActionCursor(int systemCursor) {
100            c = Cursor.getPredefinedCursor(systemCursor);
101        }
102        public Cursor cursor() {
103            return c;
104        }
105    }
106
107    private boolean lassoMode = false;
108
109    // Cache previous mouse event (needed when only the modifier keys are
110    // pressed but the mouse isn't moved)
111    private MouseEvent oldEvent = null;
112
113    private Mode mode = null;
114    private SelectionManager selectionManager;
115    private boolean cancelDrawMode = false;
116    private boolean drawTargetHighlight;
117    private boolean didMouseDrag = false;
118    /**
119     * The component this SelectAction is associated with.
120     */
121    private final MapView mv;
122    /**
123     * The old cursor before the user pressed the mouse button.
124     */
125    private Point startingDraggingPos;
126    /**
127     * point where user pressed the mouse to start movement
128     */
129    EastNorth startEN;
130    /**
131     * The last known position of the mouse.
132     */
133    private Point lastMousePos;
134    /**
135     * The time of the user mouse down event.
136     */
137    private long mouseDownTime = 0;
138    /**
139     * The pressed button of the user mouse down event.
140     */
141    private int mouseDownButton = 0;
142    /**
143     * The time of the user mouse down event.
144     */
145    private long mouseReleaseTime = 0;
146    /**
147     * The time which needs to pass between click and release before something
148     * counts as a move, in milliseconds
149     */
150    private int initialMoveDelay;
151    /**
152     * The screen distance which needs to be travelled before something
153     * counts as a move, in pixels
154     */
155    private int initialMoveThreshold;
156    private boolean initialMoveThresholdExceeded = false;
157
158    /**
159     * elements that have been highlighted in the previous iteration. Used
160     * to remove the highlight from them again as otherwise the whole data
161     * set would have to be checked.
162     */
163    private Set<OsmPrimitive> oldHighlights = new HashSet<OsmPrimitive>();
164
165    /**
166     * Create a new SelectAction
167     * @param mapFrame The MapFrame this action belongs to.
168     */
169    public SelectAction(MapFrame mapFrame) {
170        super(tr("Select"), "move/move", tr("Select, move, scale and rotate objects"),
171                Shortcut.registerShortcut("mapmode:select", tr("Mode: {0}", tr("Select")), KeyEvent.VK_S, Shortcut.DIRECT),
172                mapFrame,
173                ImageProvider.getCursor("normal", "selection"));
174        mv = mapFrame.mapView;
175        putValue("help", ht("/Action/Select"));
176        selectionManager = new SelectionManager(this, false, mv);
177        initialMoveDelay = Main.pref.getInteger("edit.initial-move-delay", 200);
178        initialMoveThreshold = Main.pref.getInteger("edit.initial-move-threshold", 5);
179    }
180
181    @Override
182    public void enterMode() {
183        super.enterMode();
184        mv.addMouseListener(this);
185        mv.addMouseMotionListener(this);
186        mv.setVirtualNodesEnabled(Main.pref.getInteger("mappaint.node.virtual-size", 8) != 0);
187        drawTargetHighlight = Main.pref.getBoolean("draw.target-highlight", true);
188        cycleManager.init();
189        virtualManager.init();
190        // This is required to update the cursors when ctrl/shift/alt is pressed
191        try {
192            Toolkit.getDefaultToolkit().addAWTEventListener(this, AWTEvent.KEY_EVENT_MASK);
193        } catch (SecurityException ex) {
194            Main.warn(ex);
195        }
196    }
197
198    @Override
199    public void exitMode() {
200        super.exitMode();
201        selectionManager.unregister(mv);
202        mv.removeMouseListener(this);
203        mv.removeMouseMotionListener(this);
204        mv.setVirtualNodesEnabled(false);
205        try {
206            Toolkit.getDefaultToolkit().removeAWTEventListener(this);
207        } catch (SecurityException ex) {
208            Main.warn(ex);
209        }
210        removeHighlighting();
211    }
212
213    int previousModifiers;
214
215     /**
216     * This is called whenever the keyboard modifier status changes
217     */
218    @Override
219    public void eventDispatched(AWTEvent e) {
220        if(oldEvent == null)
221            return;
222        // We don't have a mouse event, so we pass the old mouse event but the
223        // new modifiers.
224        int modif = ((InputEvent) e).getModifiers();
225        if (previousModifiers == modif)
226            return;
227        previousModifiers = modif;
228        if(giveUserFeedback(oldEvent, ((InputEvent) e).getModifiers())) {
229            mv.repaint();
230        }
231    }
232
233    /**
234     * handles adding highlights and updating the cursor for the given mouse event.
235     * Please note that the highlighting for merging while moving is handled via mouseDragged.
236     * @param e {@code MouseEvent} which should be used as base for the feedback
237     * @return {@code true} if repaint is required
238     */
239    private boolean giveUserFeedback(MouseEvent e) {
240        return giveUserFeedback(e, e.getModifiers());
241    }
242
243    /**
244     * handles adding highlights and updating the cursor for the given mouse event.
245     * Please note that the highlighting for merging while moving is handled via mouseDragged.
246     * @param e {@code MouseEvent} which should be used as base for the feedback
247     * @param modifiers define custom keyboard modifiers if the ones from MouseEvent are outdated or similar
248     * @return {@code true} if repaint is required
249     */
250    private boolean giveUserFeedback(MouseEvent e, int modifiers) {
251        Collection<OsmPrimitive> c = MapView.asColl(
252                mv.getNearestNodeOrWay(e.getPoint(), OsmPrimitive.isSelectablePredicate, true));
253
254        updateKeyModifiers(modifiers);
255        determineMapMode(!c.isEmpty());
256
257        HashSet<OsmPrimitive> newHighlights = new HashSet<OsmPrimitive>();
258
259        virtualManager.clear();
260        if(mode == Mode.move) {
261            if (!dragInProgress() && virtualManager.activateVirtualNodeNearPoint(e.getPoint())) {
262                DataSet ds = getCurrentDataSet();
263                if (ds != null && drawTargetHighlight) {
264                    ds.setHighlightedVirtualNodes(virtualManager.virtualWays);
265                }
266                mv.setNewCursor(SelectActionCursor.virtual_node.cursor(), this);
267                // don't highlight anything else if a virtual node will be
268                return repaintIfRequired(newHighlights);
269            }
270        }
271
272        mv.setNewCursor(getCursor(c), this);
273
274        // return early if there can't be any highlights
275        if(!drawTargetHighlight || mode != Mode.move || c.isEmpty())
276            return repaintIfRequired(newHighlights);
277
278        // CTRL toggles selection, but if while dragging CTRL means merge
279        final boolean isToggleMode = ctrl && !dragInProgress();
280        for(OsmPrimitive x : c) {
281            // only highlight primitives that will change the selection
282            // when clicked. I.e. don't highlight selected elements unless
283            // we are in toggle mode.
284            if(isToggleMode || !x.isSelected()) {
285                newHighlights.add(x);
286            }
287        }
288        return repaintIfRequired(newHighlights);
289    }
290
291    /**
292     * works out which cursor should be displayed for most of SelectAction's
293     * features. The only exception is the "move" cursor when actually dragging
294     * primitives.
295     * @param nearbyStuff  primitives near the cursor
296     * @return the cursor that should be displayed
297     */
298    private Cursor getCursor(Collection<OsmPrimitive> nearbyStuff) {
299        String c = "rect";
300        switch(mode) {
301        case move:
302            if(virtualManager.hasVirtualNode()) {
303                c = "virtual_node";
304                break;
305            }
306            final Iterator<OsmPrimitive> it = nearbyStuff.iterator();
307            final OsmPrimitive osm = it.hasNext() ? it.next() : null;
308
309            if(dragInProgress()) {
310                // only consider merge if ctrl is pressed and there are nodes in
311                // the selection that could be merged
312                if(!ctrl || getCurrentDataSet().getSelectedNodes().isEmpty()) {
313                    c = "move";
314                    break;
315                }
316                // only show merge to node cursor if nearby node and that node is currently
317                // not being dragged
318                final boolean hasTarget = osm instanceof Node && !osm.isSelected();
319                c = hasTarget ? "merge_to_node" : "merge";
320                break;
321            }
322
323            c = (osm instanceof Node) ? "node" : c;
324            c = (osm instanceof Way) ? "way" : c;
325            if(shift) {
326                c += "_add";
327            } else if(ctrl) {
328                c += osm == null || osm.isSelected() ? "_rm" : "_add";
329            }
330            break;
331        case rotate:
332            c = "rotate";
333            break;
334        case scale:
335            c = "scale";
336            break;
337        case select:
338            if (lassoMode) {
339                c = "lasso";
340            } else {
341                c = "rect" + (shift ? "_add" : (ctrl ? "_rm" : ""));
342            }
343            break;
344        }
345        return SelectActionCursor.valueOf(c).cursor();
346    }
347
348    /**
349     * Removes all existing highlights.
350     * @return true if a repaint is required
351     */
352    private boolean removeHighlighting() {
353        boolean needsRepaint = false;
354        DataSet ds = getCurrentDataSet();
355        if(ds != null && !ds.getHighlightedVirtualNodes().isEmpty()) {
356            needsRepaint = true;
357            ds.clearHighlightedVirtualNodes();
358        }
359        if(oldHighlights.isEmpty())
360            return needsRepaint;
361
362        for(OsmPrimitive prim : oldHighlights) {
363            prim.setHighlighted(false);
364        }
365        oldHighlights = new HashSet<OsmPrimitive>();
366        return true;
367    }
368
369    private boolean repaintIfRequired(Set<OsmPrimitive> newHighlights) {
370        if(!drawTargetHighlight)
371            return false;
372
373        boolean needsRepaint = false;
374        for(OsmPrimitive x : newHighlights) {
375            if(oldHighlights.contains(x)) {
376                continue;
377            }
378            needsRepaint = true;
379            x.setHighlighted(true);
380        }
381        oldHighlights.removeAll(newHighlights);
382        for(OsmPrimitive x : oldHighlights) {
383            x.setHighlighted(false);
384            needsRepaint = true;
385        }
386        oldHighlights = newHighlights;
387        return needsRepaint;
388    }
389
390     /**
391     * Look, whether any object is selected. If not, select the nearest node.
392     * If there are no nodes in the dataset, do nothing.
393     *
394     * If the user did not press the left mouse button, do nothing.
395     *
396     * Also remember the starting position of the movement and change the mouse
397     * cursor to movement.
398     */
399    @Override
400    public void mousePressed(MouseEvent e) {
401        mouseDownButton = e.getButton();
402        // return early
403        if (!mv.isActiveLayerVisible() || !(Boolean) this.getValue("active") || mouseDownButton != MouseEvent.BUTTON1)
404            return;
405
406        // left-button mouse click only is processed here
407
408        // request focus in order to enable the expected keyboard shortcuts
409        mv.requestFocus();
410
411        // update which modifiers are pressed (shift, alt, ctrl)
412        updateKeyModifiers(e);
413
414        // We don't want to change to draw tool if the user tries to (de)select
415        // stuff but accidentally clicks in an empty area when selection is empty
416        cancelDrawMode = (shift || ctrl);
417        didMouseDrag = false;
418        initialMoveThresholdExceeded = false;
419        mouseDownTime = System.currentTimeMillis();
420        lastMousePos = e.getPoint();
421        startEN = mv.getEastNorth(lastMousePos.x,lastMousePos.y);
422
423        // primitives under cursor are stored in c collection
424
425        OsmPrimitive nearestPrimitive = mv.getNearestNodeOrWay(e.getPoint(), OsmPrimitive.isSelectablePredicate, true);
426
427        determineMapMode(nearestPrimitive!=null);
428
429        switch(mode) {
430        case rotate:
431        case scale:
432            //  if nothing was selected, select primitive under cursor for scaling or rotating
433            if (getCurrentDataSet().getSelected().isEmpty()) {
434                getCurrentDataSet().setSelected(MapView.asColl(nearestPrimitive));
435            }
436
437            // Mode.select redraws when selectPrims is called
438            // Mode.move   redraws when mouseDragged is called
439            // Mode.rotate redraws here
440            // Mode.scale redraws here
441            break;
442        case move:
443            // also include case when some primitive is under cursor and no shift+ctrl / alt+ctrl is pressed
444            // so this is not movement, but selection on primitive under cursor
445            if (!cancelDrawMode && nearestPrimitive instanceof Way) {
446                virtualManager.activateVirtualNodeNearPoint(e.getPoint());
447            }
448            OsmPrimitive toSelect = cycleManager.cycleSetup(nearestPrimitive, e.getPoint());
449            selectPrims(NavigatableComponent.asColl(toSelect), false, false);
450            useLastMoveCommandIfPossible();
451            // Schedule a timer to update status line "initialMoveDelay+1" ms in the future
452            GuiHelper.scheduleTimer(initialMoveDelay+1, new ActionListener() {
453                @Override
454                public void actionPerformed(ActionEvent evt) {
455                    updateStatusLine();
456                }
457            }, false);
458            break;
459        case select:
460        default:
461            // start working with rectangle or lasso
462            selectionManager.register(mv, lassoMode);
463            selectionManager.mousePressed(e);
464            break;
465        }
466        if (giveUserFeedback(e)) {
467            mv.repaint();
468        }
469        updateStatusLine();
470    }
471
472    @Override
473    public void mouseMoved(MouseEvent e) {
474        // Mac OSX simulates with  ctrl + mouse 1  the second mouse button hence no dragging events get fired.
475        if ((Main.platform instanceof PlatformHookOsx) && (mode == Mode.rotate || mode == Mode.scale)) {
476            mouseDragged(e);
477            return;
478        }
479        oldEvent = e;
480        if(giveUserFeedback(e)) {
481            mv.repaint();
482        }
483    }
484
485    /**
486     * If the left mouse button is pressed, move all currently selected
487     * objects (if one of them is under the mouse) or the current one under the
488     * mouse (which will become selected).
489     */
490    @Override
491    public void mouseDragged(MouseEvent e) {
492        if (!mv.isActiveLayerVisible())
493            return;
494
495        // Swing sends random mouseDragged events when closing dialogs by double-clicking their top-left icon on Windows
496        // Ignore such false events to prevent issues like #7078
497        if (mouseDownButton == MouseEvent.BUTTON1 && mouseReleaseTime > mouseDownTime)
498            return;
499
500        cancelDrawMode = true;
501        if (mode == Mode.select)
502            return;
503
504        // do not count anything as a move if it lasts less than 100 milliseconds.
505        if ((mode == Mode.move) && (System.currentTimeMillis() - mouseDownTime < initialMoveDelay))
506            return;
507
508        if (mode != Mode.rotate && mode != Mode.scale) // button is pressed in rotate mode
509        {
510            if ((e.getModifiersEx() & MouseEvent.BUTTON1_DOWN_MASK) == 0)
511                return;
512        }
513
514        if (mode == Mode.move) {
515            // If ctrl is pressed we are in merge mode. Look for a nearby node,
516            // highlight it and adjust the cursor accordingly.
517            final boolean canMerge = ctrl && !getCurrentDataSet().getSelectedNodes().isEmpty();
518            final OsmPrimitive p = canMerge ? (OsmPrimitive)findNodeToMergeTo(e.getPoint()) : null;
519            boolean needsRepaint = removeHighlighting();
520            if(p != null) {
521                p.setHighlighted(true);
522                oldHighlights.add(p);
523                needsRepaint = true;
524            }
525            mv.setNewCursor(getCursor(MapView.asColl(p)), this);
526            // also update the stored mouse event, so we can display the correct cursor
527            // when dragging a node onto another one and then press CTRL to merge
528            oldEvent = e;
529            if(needsRepaint) {
530                mv.repaint();
531            }
532        }
533
534        if (startingDraggingPos == null) {
535            startingDraggingPos = new Point(e.getX(), e.getY());
536        }
537
538        if( lastMousePos == null ) {
539            lastMousePos = e.getPoint();
540            return;
541        }
542
543        if (!initialMoveThresholdExceeded) {
544            int dp = (int) lastMousePos.distance(e.getX(), e.getY());
545            if (dp < initialMoveThreshold)
546                return; // ignore small drags
547            initialMoveThresholdExceeded = true; //no more ingnoring uintil nex mouse press
548        }
549        if (e.getPoint().equals(lastMousePos))
550            return;
551
552        EastNorth currentEN = mv.getEastNorth(e.getX(), e.getY());
553
554        if (virtualManager.hasVirtualWaysToBeConstructed()) {
555            virtualManager.createMiddleNodeFromVirtual(currentEN);
556        } else {
557            if (!updateCommandWhileDragging(currentEN)) return;
558        }
559
560        mv.repaint();
561        if (mode != Mode.scale) {
562            lastMousePos = e.getPoint();
563        }
564
565        didMouseDrag = true;
566    }
567
568
569
570    @Override
571    public void mouseExited(MouseEvent e) {
572        if(removeHighlighting()) {
573            mv.repaint();
574        }
575    }
576
577
578    @Override
579    public void mouseReleased(MouseEvent e) {
580        if (!mv.isActiveLayerVisible())
581            return;
582
583        startingDraggingPos = null;
584        mouseReleaseTime = System.currentTimeMillis();
585
586        if (mode == Mode.select) {
587            selectionManager.unregister(mv);
588
589            // Select Draw Tool if no selection has been made
590            if (getCurrentDataSet().getSelected().isEmpty() && !cancelDrawMode) {
591                Main.map.selectDrawTool(true);
592                updateStatusLine();
593                return;
594            }
595        }
596
597        if (mode == Mode.move && e.getButton() == MouseEvent.BUTTON1) {
598            if (!didMouseDrag) {
599                // only built in move mode
600                virtualManager.clear();
601                // do nothing if the click was to short too be recognized as a drag,
602                // but the release position is farther than 10px away from the press position
603                if (lastMousePos == null || lastMousePos.distanceSq(e.getPoint()) < 100) {
604                    updateKeyModifiers(e);
605                    selectPrims(cycleManager.cyclePrims(), true, false);
606
607                    // If the user double-clicked a node, change to draw mode
608                    Collection<OsmPrimitive> c = getCurrentDataSet().getSelected();
609                    if (e.getClickCount() >= 2 && c.size() == 1 && c.iterator().next() instanceof Node) {
610                        // We need to do it like this as otherwise drawAction will see a double
611                        // click and switch back to SelectMode
612                        Main.worker.execute(new Runnable() {
613                            @Override
614                            public void run() {
615                                Main.map.selectDrawTool(true);
616                            }
617                        });
618                        return;
619                    }
620                }
621            } else {
622                confirmOrUndoMovement(e);
623            }
624        }
625
626        mode = null;
627
628        // simply remove any highlights if the middle click popup is active because
629        // the highlights don't depend on the cursor position there. If something was
630        // selected beforehand this would put us into move mode as well, which breaks
631        // the cycling through primitives on top of each other (see #6739).
632        if(e.getButton() == MouseEvent.BUTTON2) {
633            removeHighlighting();
634        } else {
635            giveUserFeedback(e);
636        }
637        updateStatusLine();
638    }
639
640    @Override
641    public void selectionEnded(Rectangle r, MouseEvent e) {
642        updateKeyModifiers(e);
643        selectPrims(selectionManager.getSelectedObjects(alt), true, true);
644    }
645
646    /**
647     * sets the mapmode according to key modifiers and if there are any
648     * selectables nearby. Everything has to be pre-determined for this
649     * function; its main purpose is to centralize what the modifiers do.
650     * @param hasSelectionNearby
651     */
652    private void determineMapMode(boolean hasSelectionNearby) {
653        if (shift && ctrl) {
654            mode = Mode.rotate;
655        } else if (alt && ctrl) {
656            mode = Mode.scale;
657        } else if (hasSelectionNearby || dragInProgress()) {
658            mode = Mode.move;
659        } else {
660            mode = Mode.select;
661        }
662    }
663
664    /** returns true whenever elements have been grabbed and moved (i.e. the initial
665     * thresholds have been exceeded) and is still in progress (i.e. mouse button
666     * still pressed)
667     */
668    final private boolean dragInProgress() {
669        return didMouseDrag && startingDraggingPos != null;
670    }
671
672
673    /**
674     * Create or update data modification command while dragging mouse - implementation of
675     * continuous moving, scaling and rotation
676     * @param currentEN - mouse position
677     * @return status of action (<code>true</code> when action was performed)
678     */
679    private boolean updateCommandWhileDragging(EastNorth currentEN) {
680        // Currently we support only transformations which do not affect relations.
681        // So don't add them in the first place to make handling easier
682        Collection<OsmPrimitive> selection = getCurrentDataSet().getSelectedNodesAndWays();
683        if (selection.isEmpty()) { // if nothing was selected to drag, just select nearest node/way to the cursor
684            OsmPrimitive nearestPrimitive = mv.getNearestNodeOrWay(mv.getPoint(startEN), OsmPrimitive.isSelectablePredicate, true);
685            getCurrentDataSet().setSelected(nearestPrimitive);
686        }
687
688        Collection<Node> affectedNodes = AllNodesVisitor.getAllNodes(selection);
689        // for these transformations, having only one node makes no sense - quit silently
690        if (affectedNodes.size() < 2 && (mode == Mode.rotate || mode == Mode.scale)) {
691            return false;
692        }
693        Command c = getLastCommand();
694        if (mode == Mode.move) {
695            if (startEN == null) return false; // fix #8128
696            getCurrentDataSet().beginUpdate();
697            if (c instanceof MoveCommand && affectedNodes.equals(((MoveCommand) c).getParticipatingPrimitives())) {
698                ((MoveCommand) c).saveCheckpoint();
699                ((MoveCommand) c).applyVectorTo(currentEN);
700            } else {
701                Main.main.undoRedo.add(
702                        c = new MoveCommand(selection, startEN, currentEN));
703            }
704            for (Node n : affectedNodes) {
705                LatLon ll = n.getCoor();
706                if (ll != null && ll.isOutSideWorld()) {
707                    // Revert move
708                    ((MoveCommand) c).resetToCheckpoint();
709                    getCurrentDataSet().endUpdate();
710                    JOptionPane.showMessageDialog(
711                            Main.parent,
712                            tr("Cannot move objects outside of the world."),
713                            tr("Warning"),
714                            JOptionPane.WARNING_MESSAGE);
715                    mv.setNewCursor(cursor, this);
716                    return false;
717                }
718            }
719        } else {
720            startEN = currentEN; // drag can continue after scaling/rotation
721
722            if (mode != Mode.rotate && mode != Mode.scale) {
723                return false;
724            }
725
726            getCurrentDataSet().beginUpdate();
727
728            if (mode == Mode.rotate) {
729                if (c instanceof RotateCommand && affectedNodes.equals(((RotateCommand) c).getTransformedNodes())) {
730                    ((RotateCommand) c).handleEvent(currentEN);
731                } else {
732                    Main.main.undoRedo.add(new RotateCommand(selection, currentEN));
733                }
734            } else if (mode == Mode.scale) {
735                if (c instanceof ScaleCommand && affectedNodes.equals(((ScaleCommand) c).getTransformedNodes())) {
736                    ((ScaleCommand) c).handleEvent(currentEN);
737                } else {
738                    Main.main.undoRedo.add(new ScaleCommand(selection, currentEN));
739                }
740            }
741
742            Collection<Way> ways = getCurrentDataSet().getSelectedWays();
743            if (doesImpactStatusLine(affectedNodes, ways)) {
744                Main.map.statusLine.setDist(ways);
745            }
746        }
747        getCurrentDataSet().endUpdate();
748        return true;
749    }
750
751    private boolean doesImpactStatusLine(Collection<Node> affectedNodes, Collection<Way> selectedWays) {
752        for (Way w : selectedWays) {
753            for (Node n : w.getNodes()) {
754                if (affectedNodes.contains(n)) {
755                    return true;
756                }
757            }
758        }
759        return false;
760    }
761
762    /**
763     * Adapt last move command (if it is suitable) to work with next drag, started at point startEN
764     */
765    private void useLastMoveCommandIfPossible() {
766        Command c = getLastCommand();
767        Collection<Node> affectedNodes = AllNodesVisitor.getAllNodes(getCurrentDataSet().getSelected());
768        if (c instanceof MoveCommand && affectedNodes.equals(((MoveCommand) c).getParticipatingPrimitives())) {
769            // old command was created with different base point of movement, we need to recalculate it
770            ((MoveCommand) c).changeStartPoint(startEN);
771        }
772    }
773
774    /**
775     * Obtain command in undoRedo stack to "continue" when dragging
776     */
777    private Command getLastCommand() {
778        Command c = !Main.main.undoRedo.commands.isEmpty()
779                ? Main.main.undoRedo.commands.getLast() : null;
780        if (c instanceof SequenceCommand) {
781            c = ((SequenceCommand) c).getLastCommand();
782        }
783        return c;
784    }
785
786    /**
787     * Present warning in case of large and possibly unwanted movements and undo
788     * unwanted movements.
789     *
790     * @param e the mouse event causing the action (mouse released)
791     */
792    private void confirmOrUndoMovement(MouseEvent e) {
793        int max = Main.pref.getInteger("warn.move.maxelements", 20), limit = max;
794        for (OsmPrimitive osm : getCurrentDataSet().getSelected()) {
795            if (osm instanceof Way) {
796                limit -= ((Way) osm).getNodes().size();
797            }
798            if ((limit -= 1) < 0) {
799                break;
800            }
801        }
802        if (limit < 0) {
803            ExtendedDialog ed = new ExtendedDialog(
804                    Main.parent,
805                    tr("Move elements"),
806                    new String[]{tr("Move them"), tr("Undo move")});
807            ed.setButtonIcons(new String[]{"reorder.png", "cancel.png"});
808            ed.setContent(tr("You moved more than {0} elements. " + "Moving a large number of elements is often an error.\n" + "Really move them?", max));
809            ed.setCancelButton(2);
810            ed.toggleEnable("movedManyElements");
811            ed.showDialog();
812
813            if (ed.getValue() != 1) {
814                Main.main.undoRedo.undo();
815            }
816        } else {
817            // if small number of elements were moved,
818            updateKeyModifiers(e);
819            if (ctrl) mergePrims(e.getPoint());
820        }
821        getCurrentDataSet().fireSelectionChanged();
822    }
823
824    /**
825     * Merges the selected nodes to the one closest to the given mouse position if the control
826     * key is pressed. If there is no such node, no action will be done and no error will be
827     * reported. If there is, it will execute the merge and add it to the undo buffer.
828     */
829    final private void mergePrims(Point p) {
830        Collection<Node> selNodes = getCurrentDataSet().getSelectedNodes();
831        if (selNodes.isEmpty())
832            return;
833
834        Node target = findNodeToMergeTo(p);
835        if (target == null)
836            return;
837
838        Collection<Node> nodesToMerge = new LinkedList<Node>(selNodes);
839        nodesToMerge.add(target);
840        MergeNodesAction.doMergeNodes(Main.main.getEditLayer(), nodesToMerge, target);
841    }
842
843    /**
844     * Tries to find a node to merge to when in move-merge mode for the current mouse
845     * position. Either returns the node or null, if no suitable one is nearby.
846     */
847    final private Node findNodeToMergeTo(Point p) {
848        Collection<Node> target = mv.getNearestNodes(p,
849                getCurrentDataSet().getSelectedNodes(),
850                OsmPrimitive.isSelectablePredicate);
851        return target.isEmpty() ? null : target.iterator().next();
852    }
853
854    private void selectPrims(Collection<OsmPrimitive> prims, boolean released, boolean area) {
855        DataSet ds = getCurrentDataSet();
856
857        // not allowed together: do not change dataset selection, return early
858        // Virtual Ways: if non-empty the cursor is above a virtual node. So don't highlight
859        // anything if about to drag the virtual node (i.e. !released) but continue if the
860        // cursor is only released above a virtual node by accident (i.e. released). See #7018
861        if (ds == null || (shift && ctrl) || (ctrl && !released) || (virtualManager.hasVirtualWaysToBeConstructed() && !released))
862            return;
863
864        if (!released) {
865            // Don't replace the selection if the user clicked on a
866            // selected object (it breaks moving of selected groups).
867            // Do it later, on mouse release.
868            shift |= ds.getSelected().containsAll(prims);
869        }
870
871        if (ctrl) {
872            // Ctrl on an item toggles its selection status,
873            // but Ctrl on an *area* just clears those items
874            // out of the selection.
875            if (area) {
876                ds.clearSelection(prims);
877            } else {
878                ds.toggleSelected(prims);
879            }
880        } else if (shift) {
881            // add prims to an existing selection
882            ds.addSelected(prims);
883        } else {
884            // clear selection, then select the prims clicked
885            ds.setSelected(prims);
886        }
887    }
888
889    @Override
890    public String getModeHelpText() {
891        if (mouseDownButton == MouseEvent.BUTTON1 && mouseReleaseTime < mouseDownTime) {
892            if (mode == Mode.select)
893                return tr("Release the mouse button to select the objects in the rectangle.");
894            else if (mode == Mode.move && (System.currentTimeMillis() - mouseDownTime >= initialMoveDelay)) {
895                final boolean canMerge = getCurrentDataSet()!=null && !getCurrentDataSet().getSelectedNodes().isEmpty();
896                final String mergeHelp = canMerge ? (" " + tr("Ctrl to merge with nearest node.")) : "";
897                return tr("Release the mouse button to stop moving.") + mergeHelp;
898            } else if (mode == Mode.rotate)
899                return tr("Release the mouse button to stop rotating.");
900            else if (mode == Mode.scale)
901                return tr("Release the mouse button to stop scaling.");
902        }
903        return tr("Move objects by dragging; Shift to add to selection (Ctrl to toggle); Shift-Ctrl to rotate selected; Alt-Ctrl to scale selected; or change selection");
904    }
905
906    @Override
907    public boolean layerIsSupported(Layer l) {
908        return l instanceof OsmDataLayer;
909    }
910
911    /**
912     * Enable or diable the lasso mode
913     * @param lassoMode true to enable the lasso mode, false otherwise
914     */
915    public void setLassoMode(boolean lassoMode) {
916        this.selectionManager.setLassoMode(lassoMode);
917        this.lassoMode = lassoMode;
918    }
919
920    CycleManager cycleManager = new CycleManager();
921    VirtualManager virtualManager = new VirtualManager();
922
923    private class CycleManager {
924
925        private Collection<OsmPrimitive> cycleList = Collections.emptyList();
926        private boolean cyclePrims = false;
927        private OsmPrimitive cycleStart = null;
928        private boolean waitForMouseUpParameter;
929        private boolean multipleMatchesParameter;
930        /**
931         * read preferences
932         */
933        private void init() {
934            waitForMouseUpParameter = Main.pref.getBoolean("mappaint.select.waits-for-mouse-up", false);
935            multipleMatchesParameter = Main.pref.getBoolean("selectaction.cycles.multiple.matches", false);
936        }
937
938        /**
939         * Determine prmitive to be selected and build cycleList
940         * @param nearest primitive found by simple method
941         * @param p point where user clicked
942         * @return OsmPrimitive to be selected
943         */
944        private OsmPrimitive cycleSetup(OsmPrimitive nearest, Point p) {
945            OsmPrimitive osm = null;
946
947            if (nearest != null) {
948                osm = nearest;
949
950                if (!(alt || multipleMatchesParameter)) {
951                    // no real cycling, just one element in cycle list
952                    cycleList = MapView.asColl(osm);
953
954                    if (waitForMouseUpParameter) {
955                        // prefer a selected nearest node or way, if possible
956                        osm = mv.getNearestNodeOrWay(p, OsmPrimitive.isSelectablePredicate, true);
957                    }
958                } else {
959                    // Alt + left mouse button pressed: we need to build cycle list
960                    cycleList = mv.getAllNearest(p, OsmPrimitive.isSelectablePredicate);
961
962                    if (cycleList.size() > 1) {
963                        cyclePrims = false;
964
965                        // find first already selected element in cycle list
966                        OsmPrimitive old = osm;
967                        for (OsmPrimitive o : cycleList) {
968                            if (o.isSelected()) {
969                                cyclePrims = true;
970                                osm = o;
971                                break;
972                            }
973                        }
974
975                        // special case:  for cycle groups of 2, we can toggle to the
976                        // true nearest primitive on mousePressed right away
977                        if (cycleList.size() == 2 && !waitForMouseUpParameter) {
978                            if (!(osm.equals(old) || osm.isNew() || ctrl)) {
979                                cyclePrims = false;
980                                osm = old;
981                            } // else defer toggling to mouseRelease time in those cases:
982                            /*
983                             * osm == old -- the true nearest node is the
984                             * selected one osm is a new node -- do not break
985                             * unglue ways in ALT mode ctrl is pressed -- ctrl
986                             * generally works on mouseReleased
987                             */
988                        }
989                    }
990                }
991            }
992            return osm;
993        }
994
995        /**
996         * Modifies current selection state and returns the next element in a
997         * selection cycle given by
998         * <code>cycleList</code> field
999         * @return the next element of cycle list
1000         */
1001        private Collection<OsmPrimitive> cyclePrims() {
1002            OsmPrimitive nxt = null;
1003
1004            if (cycleList.size() <= 1) {
1005                // no real cycling, just return one-element collection with nearest primitive in it
1006                return cycleList;
1007            }
1008//          updateKeyModifiers(e); // already called before !
1009
1010            DataSet ds = getCurrentDataSet();
1011            OsmPrimitive first = cycleList.iterator().next(), foundInDS = null;
1012            nxt = first;
1013
1014            if (cyclePrims && shift) {
1015                for (Iterator<OsmPrimitive> i = cycleList.iterator(); i.hasNext();) {
1016                    nxt = i.next();
1017                    if (!nxt.isSelected()) {
1018                        break; // take first primitive in cycleList not in sel
1019                    }
1020                }
1021                // if primitives 1,2,3 are under cursor, [Alt-press] [Shift-release] gives 1 -> 12 -> 123
1022            } else {
1023                for (Iterator<OsmPrimitive> i = cycleList.iterator(); i.hasNext();) {
1024                    nxt = i.next();
1025                    if (nxt.isSelected()) {
1026                        foundInDS = nxt;
1027                        // first selected primitive in cycleList is found
1028                        if (cyclePrims || ctrl) {
1029                            ds.clearSelection(foundInDS); // deselect it
1030                            nxt = i.hasNext() ? i.next() : first;
1031                            // return next one in cycle list (last->first)
1032                        }
1033                        break; // take next primitive in cycleList
1034                    }
1035                }
1036            }
1037
1038            // if "no-alt-cycling" is enabled, Ctrl-Click arrives here.
1039            if (ctrl) {
1040                // a member of cycleList was found in the current dataset selection
1041                if (foundInDS != null) {
1042                    // mouse was moved to a different selection group w/ a previous sel
1043                    if (!cycleList.contains(cycleStart)) {
1044                        ds.clearSelection(cycleList);
1045                        cycleStart = foundInDS;
1046                    } else if (cycleStart.equals(nxt)) {
1047                        // loop detected, insert deselect step
1048                        ds.addSelected(nxt);
1049                    }
1050                } else {
1051                    // setup for iterating a sel group again or a new, different one..
1052                    nxt = (cycleList.contains(cycleStart)) ? cycleStart : first;
1053                    cycleStart = nxt;
1054                }
1055            } else {
1056                cycleStart = null;
1057            }
1058            // return one-element collection with one element to be selected (or added  to selection)
1059            return MapView.asColl(nxt);
1060        }
1061    }
1062
1063    private class VirtualManager {
1064
1065        private Node virtualNode = null;
1066        private Collection<WaySegment> virtualWays = new LinkedList<WaySegment>();
1067        private int nodeVirtualSize;
1068        private int virtualSnapDistSq2;
1069        private int virtualSpace;
1070
1071        private void init() {
1072            nodeVirtualSize = Main.pref.getInteger("mappaint.node.virtual-size", 8);
1073            int virtualSnapDistSq = Main.pref.getInteger("mappaint.node.virtual-snap-distance", 8);
1074            virtualSnapDistSq2 = virtualSnapDistSq*virtualSnapDistSq;
1075            virtualSpace = Main.pref.getInteger("mappaint.node.virtual-space", 70);
1076        }
1077
1078        /**
1079         * Calculate a virtual node if there is enough visual space to draw a
1080         * crosshair node and the middle of a way segment is clicked. If the
1081         * user drags the crosshair node, it will be added to all ways in
1082         * <code>virtualWays</code>.
1083         *
1084         * @param p the point clicked
1085         * @return whether
1086         * <code>virtualNode</code> and
1087         * <code>virtualWays</code> were setup.
1088         */
1089        private boolean activateVirtualNodeNearPoint(Point p) {
1090            if (nodeVirtualSize > 0) {
1091
1092                Collection<WaySegment> selVirtualWays = new LinkedList<WaySegment>();
1093                Pair<Node, Node> vnp = null, wnp = new Pair<Node, Node>(null, null);
1094
1095                Way w = null;
1096                for (WaySegment ws : mv.getNearestWaySegments(p, OsmPrimitive.isSelectablePredicate)) {
1097                    w = ws.way;
1098
1099                    Point2D p1 = mv.getPoint2D(wnp.a = w.getNode(ws.lowerIndex));
1100                    Point2D p2 = mv.getPoint2D(wnp.b = w.getNode(ws.lowerIndex + 1));
1101                    if (WireframeMapRenderer.isLargeSegment(p1, p2, virtualSpace)) {
1102                        Point2D pc = new Point2D.Double((p1.getX() + p2.getX()) / 2, (p1.getY() + p2.getY()) / 2);
1103                        if (p.distanceSq(pc) < virtualSnapDistSq2) {
1104                            // Check that only segments on top of each other get added to the
1105                            // virtual ways list. Otherwise ways that coincidentally have their
1106                            // virtual node at the same spot will be joined which is likely unwanted
1107                            Pair.sort(wnp);
1108                            if (vnp == null) {
1109                                vnp = new Pair<Node, Node>(wnp.a, wnp.b);
1110                                virtualNode = new Node(mv.getLatLon(pc.getX(), pc.getY()));
1111                            }
1112                            if (vnp.equals(wnp)) {
1113                                // if mutiple line segments have the same points,
1114                                // add all segments to be splitted to virtualWays list
1115                                // if some lines are selected, only their segments will go to virtualWays
1116                                (w.isSelected() ? selVirtualWays : virtualWays).add(ws);
1117                            }
1118                        }
1119                    }
1120                }
1121
1122                if (!selVirtualWays.isEmpty()) {
1123                    virtualWays = selVirtualWays;
1124                }
1125            }
1126
1127            return !virtualWays.isEmpty();
1128        }
1129
1130        private void createMiddleNodeFromVirtual(EastNorth currentEN) {
1131            Collection<Command> virtualCmds = new LinkedList<Command>();
1132            virtualCmds.add(new AddCommand(virtualNode));
1133            for (WaySegment virtualWay : virtualWays) {
1134                Way w = virtualWay.way;
1135                Way wnew = new Way(w);
1136                wnew.addNode(virtualWay.lowerIndex + 1, virtualNode);
1137                virtualCmds.add(new ChangeCommand(w, wnew));
1138            }
1139            virtualCmds.add(new MoveCommand(virtualNode, startEN, currentEN));
1140            String text = trn("Add and move a virtual new node to way",
1141                    "Add and move a virtual new node to {0} ways", virtualWays.size(),
1142                    virtualWays.size());
1143            Main.main.undoRedo.add(new SequenceCommand(text, virtualCmds));
1144            getCurrentDataSet().setSelected(Collections.singleton((OsmPrimitive) virtualNode));
1145            clear();
1146        }
1147
1148        private void clear() {
1149            virtualWays.clear();
1150            virtualNode = null;
1151        }
1152
1153        private boolean hasVirtualNode() {
1154            return virtualNode != null;
1155        }
1156
1157        private boolean hasVirtualWaysToBeConstructed() {
1158            return !virtualWays.isEmpty();
1159        }
1160    }
1161}