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.Cursor;
009import java.awt.Point;
010import java.awt.Rectangle;
011import java.awt.event.KeyEvent;
012import java.awt.event.MouseEvent;
013import java.awt.geom.Point2D;
014import java.util.Collection;
015import java.util.Collections;
016import java.util.HashSet;
017import java.util.Iterator;
018import java.util.LinkedList;
019import java.util.List;
020import java.util.Optional;
021
022import javax.swing.JOptionPane;
023
024import org.openstreetmap.josm.actions.MergeNodesAction;
025import org.openstreetmap.josm.command.AddCommand;
026import org.openstreetmap.josm.command.ChangeNodesCommand;
027import org.openstreetmap.josm.command.Command;
028import org.openstreetmap.josm.command.MoveCommand;
029import org.openstreetmap.josm.command.RotateCommand;
030import org.openstreetmap.josm.command.ScaleCommand;
031import org.openstreetmap.josm.command.SequenceCommand;
032import org.openstreetmap.josm.data.SystemOfMeasurement;
033import org.openstreetmap.josm.data.UndoRedoHandler;
034import org.openstreetmap.josm.data.coor.EastNorth;
035import org.openstreetmap.josm.data.osm.DataSet;
036import org.openstreetmap.josm.data.osm.Node;
037import org.openstreetmap.josm.data.osm.OsmData;
038import org.openstreetmap.josm.data.osm.OsmPrimitive;
039import org.openstreetmap.josm.data.osm.Way;
040import org.openstreetmap.josm.data.osm.WaySegment;
041import org.openstreetmap.josm.data.osm.visitor.AllNodesVisitor;
042import org.openstreetmap.josm.data.osm.visitor.paint.WireframeMapRenderer;
043import org.openstreetmap.josm.gui.ExtendedDialog;
044import org.openstreetmap.josm.gui.MainApplication;
045import org.openstreetmap.josm.gui.MapFrame;
046import org.openstreetmap.josm.gui.MapView;
047import org.openstreetmap.josm.gui.MapViewState.MapViewPoint;
048import org.openstreetmap.josm.gui.SelectionManager;
049import org.openstreetmap.josm.gui.SelectionManager.SelectionEnded;
050import org.openstreetmap.josm.gui.layer.Layer;
051import org.openstreetmap.josm.gui.layer.OsmDataLayer;
052import org.openstreetmap.josm.gui.util.GuiHelper;
053import org.openstreetmap.josm.gui.util.KeyPressReleaseListener;
054import org.openstreetmap.josm.gui.util.ModifierExListener;
055import org.openstreetmap.josm.spi.preferences.Config;
056import org.openstreetmap.josm.tools.ImageProvider;
057import org.openstreetmap.josm.tools.Logging;
058import org.openstreetmap.josm.tools.Pair;
059import org.openstreetmap.josm.tools.PlatformManager;
060import org.openstreetmap.josm.tools.Shortcut;
061import org.openstreetmap.josm.tools.Utils;
062
063/**
064 * Move is an action that can move all kind of OsmPrimitives (except keys for now).
065 *
066 * If an selected object is under the mouse when dragging, move all selected objects.
067 * If an unselected object is under the mouse when dragging, it becomes selected
068 * and will be moved.
069 * If no object is under the mouse, move all selected objects (if any)
070 *
071 * On Mac OS X, Ctrl + mouse button 1 simulates right click (map move), so the
072 * feature "selection remove" is disabled on this platform.
073 */
074public class SelectAction extends MapMode implements ModifierExListener, KeyPressReleaseListener, SelectionEnded {
075
076    private static final String NORMAL = /* ICON(cursor/)*/ "normal";
077
078    /**
079     * Select action mode.
080     * @since 7543
081     */
082    public enum Mode {
083        /** "MOVE" means either dragging or select if no mouse movement occurs (i.e. just clicking) */
084        MOVE,
085        /** "ROTATE" allows to apply a rotation transformation on the selected object (see {@link RotateCommand}) */
086        ROTATE,
087        /** "SCALE" allows to apply a scaling transformation on the selected object (see {@link ScaleCommand}) */
088        SCALE,
089        /** "SELECT" means the selection rectangle */
090        SELECT
091    }
092
093    // contains all possible cases the cursor can be in the SelectAction
094    enum SelectActionCursor {
095
096        rect(NORMAL, /* ICON(cursor/modifier/)*/ "selection"),
097        rect_add(NORMAL, /* ICON(cursor/modifier/)*/ "select_add"),
098        rect_rm(NORMAL, /* ICON(cursor/modifier/)*/ "select_remove"),
099        way(NORMAL, /* ICON(cursor/modifier/)*/ "select_way"),
100        way_add(NORMAL, /* ICON(cursor/modifier/)*/ "select_way_add"),
101        way_rm(NORMAL, /* ICON(cursor/modifier/)*/ "select_way_remove"),
102        node(NORMAL, /* ICON(cursor/modifier/)*/ "select_node"),
103        node_add(NORMAL, /* ICON(cursor/modifier/)*/ "select_node_add"),
104        node_rm(NORMAL, /* ICON(cursor/modifier/)*/ "select_node_remove"),
105        virtual_node(NORMAL, /* ICON(cursor/modifier/)*/ "addnode"),
106        scale(/* ICON(cursor/)*/ "scale", null),
107        rotate(/* ICON(cursor/)*/ "rotate", null),
108        merge(/* ICON(cursor/)*/ "crosshair", null),
109        lasso(NORMAL, /* ICON(cursor/modifier/)*/ "rope"),
110        merge_to_node(/* ICON(cursor/)*/ "crosshair", /* ICON(cursor/modifier/)*/"joinnode"),
111        move(Cursor.MOVE_CURSOR);
112
113        @SuppressWarnings("ImmutableEnumChecker")
114        private final Cursor c;
115        SelectActionCursor(String main, String sub) {
116            c = ImageProvider.getCursor(main, sub);
117        }
118
119        SelectActionCursor(int systemCursor) {
120            c = Cursor.getPredefinedCursor(systemCursor);
121        }
122
123        /**
124         * Returns the action cursor.
125         * @return the cursor
126         */
127        public Cursor cursor() {
128            return c;
129        }
130    }
131
132    private boolean lassoMode;
133    private boolean repeatedKeySwitchLassoOption;
134
135    // Cache previous mouse event (needed when only the modifier keys are
136    // pressed but the mouse isn't moved)
137    private MouseEvent oldEvent;
138
139    private Mode mode;
140    private final transient SelectionManager selectionManager;
141    private boolean cancelDrawMode;
142    private boolean drawTargetHighlight;
143    private boolean didMouseDrag;
144    /**
145     * The component this SelectAction is associated with.
146     */
147    private final MapView mv;
148    /**
149     * The old cursor before the user pressed the mouse button.
150     */
151    private Point startingDraggingPos;
152    /**
153     * point where user pressed the mouse to start movement
154     */
155    private EastNorth startEN;
156    /**
157     * The last known position of the mouse.
158     */
159    private Point lastMousePos;
160    /**
161     * The time of the user mouse down event.
162     */
163    private long mouseDownTime;
164    /**
165     * The pressed button of the user mouse down event.
166     */
167    private int mouseDownButton;
168    /**
169     * The time of the user mouse down event.
170     */
171    private long mouseReleaseTime;
172    /**
173     * The time which needs to pass between click and release before something
174     * counts as a move, in milliseconds
175     */
176    private int initialMoveDelay;
177    /**
178     * The screen distance which needs to be travelled before something
179     * counts as a move, in pixels
180     */
181    private int initialMoveThreshold;
182    private boolean initialMoveThresholdExceeded;
183
184    /**
185     * elements that have been highlighted in the previous iteration. Used
186     * to remove the highlight from them again as otherwise the whole data
187     * set would have to be checked.
188     */
189    private transient Optional<OsmPrimitive> currentHighlight = Optional.empty();
190
191    /**
192     * Create a new SelectAction
193     * @param mapFrame The MapFrame this action belongs to.
194     */
195    public SelectAction(MapFrame mapFrame) {
196        super(tr("Select mode"), "move/move", tr("Select, move, scale and rotate objects"),
197                Shortcut.registerShortcut("mapmode:select", tr("Mode: {0}", tr("Select mode")), KeyEvent.VK_S, Shortcut.DIRECT),
198                ImageProvider.getCursor("normal", "selection"));
199        mv = mapFrame.mapView;
200        setHelpId(ht("/Action/Select"));
201        selectionManager = new SelectionManager(this, false, mv);
202    }
203
204    @Override
205    public void enterMode() {
206        super.enterMode();
207        mv.addMouseListener(this);
208        mv.addMouseMotionListener(this);
209        mv.setVirtualNodesEnabled(Config.getPref().getInt("mappaint.node.virtual-size", 8) != 0);
210        drawTargetHighlight = Config.getPref().getBoolean("draw.target-highlight", true);
211        initialMoveDelay = Config.getPref().getInt("edit.initial-move-delay", 200);
212        initialMoveThreshold = Config.getPref().getInt("edit.initial-move-threshold", 5);
213        repeatedKeySwitchLassoOption = Config.getPref().getBoolean("mappaint.select.toggle-lasso-on-repeated-S", true);
214        cycleManager.init();
215        virtualManager.init();
216        // This is required to update the cursors when ctrl/shift/alt is pressed
217        MapFrame map = MainApplication.getMap();
218        map.keyDetector.addModifierExListener(this);
219        map.keyDetector.addKeyListener(this);
220    }
221
222    @Override
223    public void exitMode() {
224        super.exitMode();
225        cycleManager.cycleStart = null;
226        cycleManager.cycleList = asColl(null);
227        selectionManager.unregister(mv);
228        mv.removeMouseListener(this);
229        mv.removeMouseMotionListener(this);
230        mv.setVirtualNodesEnabled(false);
231        MapFrame map = MainApplication.getMap();
232        map.keyDetector.removeModifierExListener(this);
233        map.keyDetector.removeKeyListener(this);
234        removeHighlighting();
235        virtualManager.clear();
236    }
237
238    @Override
239    public void modifiersExChanged(int modifiers) {
240        if (!MainApplication.isDisplayingMapView() || oldEvent == null) return;
241        if (giveUserFeedback(oldEvent, modifiers)) {
242            mv.repaint();
243        }
244    }
245
246    /**
247     * handles adding highlights and updating the cursor for the given mouse event.
248     * Please note that the highlighting for merging while moving is handled via mouseDragged.
249     * @param e {@code MouseEvent} which should be used as base for the feedback
250     * @return {@code true} if repaint is required
251     */
252    private boolean giveUserFeedback(MouseEvent e) {
253        return giveUserFeedback(e, e.getModifiersEx());
254    }
255
256    /**
257     * handles adding highlights and updating the cursor for the given mouse event.
258     * Please note that the highlighting for merging while moving is handled via mouseDragged.
259     * @param e {@code MouseEvent} which should be used as base for the feedback
260     * @param modifiers define custom keyboard extended modifiers if the ones from MouseEvent are outdated or similar
261     * @return {@code true} if repaint is required
262     */
263    private boolean giveUserFeedback(MouseEvent e, int modifiers) {
264        Optional<OsmPrimitive> c = Optional.ofNullable(
265                mv.getNearestNodeOrWay(e.getPoint(), mv.isSelectablePredicate, true));
266
267        updateKeyModifiersEx(modifiers);
268        determineMapMode(c.isPresent());
269
270        Optional<OsmPrimitive> newHighlight = Optional.empty();
271
272        virtualManager.clear();
273        if (mode == Mode.MOVE && !dragInProgress() && virtualManager.activateVirtualNodeNearPoint(e.getPoint())) {
274            DataSet ds = getLayerManager().getActiveDataSet();
275            if (ds != null && drawTargetHighlight) {
276                ds.setHighlightedVirtualNodes(virtualManager.virtualWays);
277            }
278            mv.setNewCursor(SelectActionCursor.virtual_node.cursor(), this);
279            // don't highlight anything else if a virtual node will be
280            return repaintIfRequired(newHighlight);
281        }
282
283        mv.setNewCursor(getCursor(c.orElse(null)), this);
284
285        // return early if there can't be any highlights
286        if (!drawTargetHighlight || (mode != Mode.MOVE && mode != Mode.SELECT) || !c.isPresent())
287            return repaintIfRequired(newHighlight);
288
289        // CTRL toggles selection, but if while dragging CTRL means merge
290        final boolean isToggleMode = ctrl && !dragInProgress();
291        if (c.isPresent() && (isToggleMode || !c.get().isSelected())) {
292            // only highlight primitives that will change the selection
293            // when clicked. I.e. don't highlight selected elements unless
294            // we are in toggle mode.
295            newHighlight = c;
296        }
297        return repaintIfRequired(newHighlight);
298    }
299
300    /**
301     * works out which cursor should be displayed for most of SelectAction's
302     * features. The only exception is the "move" cursor when actually dragging
303     * primitives.
304     * @param nearbyStuff primitives near the cursor
305     * @return the cursor that should be displayed
306     */
307    private Cursor getCursor(OsmPrimitive nearbyStuff) {
308        String c = "rect";
309        switch(mode) {
310        case MOVE:
311            if (virtualManager.hasVirtualNode()) {
312                c = "virtual_node";
313                break;
314            }
315            final OsmPrimitive osm = nearbyStuff;
316
317            if (dragInProgress()) {
318                // only consider merge if ctrl is pressed and there are nodes in
319                // the selection that could be merged
320                if (!ctrl || getLayerManager().getEditDataSet().getSelectedNodes().isEmpty()) {
321                    c = "move";
322                    break;
323                }
324                // only show merge to node cursor if nearby node and that node is currently
325                // not being dragged
326                final boolean hasTarget = osm instanceof Node && !osm.isSelected();
327                c = hasTarget ? "merge_to_node" : "merge";
328                break;
329            }
330
331            c = (osm instanceof Node) ? "node" : c;
332            c = (osm instanceof Way) ? "way" : c;
333            if (shift) {
334                c += "_add";
335            } else if (ctrl) {
336                c += osm == null || osm.isSelected() ? "_rm" : "_add";
337            }
338            break;
339        case ROTATE:
340            c = "rotate";
341            break;
342        case SCALE:
343            c = "scale";
344            break;
345        case SELECT:
346            if (lassoMode) {
347                c = "lasso";
348            } else {
349                c = "rect" + (shift ? "_add" : (ctrl && !PlatformManager.isPlatformOsx() ? "_rm" : ""));
350            }
351            break;
352        }
353        return SelectActionCursor.valueOf(c).cursor();
354    }
355
356    /**
357     * Removes all existing highlights.
358     * @return true if a repaint is required
359     */
360    private boolean removeHighlighting() {
361        boolean needsRepaint = false;
362        OsmData<?, ?, ?, ?> ds = getLayerManager().getActiveData();
363        if (ds != null && !ds.getHighlightedVirtualNodes().isEmpty()) {
364            needsRepaint = true;
365            ds.clearHighlightedVirtualNodes();
366        }
367        if (!currentHighlight.isPresent()) {
368            return needsRepaint;
369        } else {
370            currentHighlight.get().setHighlighted(false);
371        }
372        currentHighlight = Optional.empty();
373        return true;
374    }
375
376    private boolean repaintIfRequired(Optional<OsmPrimitive> newHighlight) {
377        if (!drawTargetHighlight || currentHighlight.equals(newHighlight))
378            return false;
379        currentHighlight.ifPresent(osm -> osm.setHighlighted(false));
380        newHighlight.ifPresent(osm -> osm.setHighlighted(true));
381        currentHighlight = newHighlight;
382        return true;
383    }
384
385    /**
386     * Look, whether any object is selected. If not, select the nearest node.
387     * If there are no nodes in the dataset, do nothing.
388     *
389     * If the user did not press the left mouse button, do nothing.
390     *
391     * Also remember the starting position of the movement and change the mouse
392     * cursor to movement.
393     */
394    @Override
395    public void mousePressed(MouseEvent e) {
396        mouseDownButton = e.getButton();
397        // return early
398        if (!mv.isActiveLayerVisible() || !(Boolean) this.getValue("active") || mouseDownButton != MouseEvent.BUTTON1)
399            return;
400
401        // left-button mouse click only is processed here
402
403        // request focus in order to enable the expected keyboard shortcuts
404        mv.requestFocus();
405
406        // update which modifiers are pressed (shift, alt, ctrl)
407        updateKeyModifiers(e);
408
409        // We don't want to change to draw tool if the user tries to (de)select
410        // stuff but accidentally clicks in an empty area when selection is empty
411        cancelDrawMode = shift || ctrl;
412        didMouseDrag = false;
413        initialMoveThresholdExceeded = false;
414        mouseDownTime = System.currentTimeMillis();
415        lastMousePos = e.getPoint();
416        startEN = mv.getEastNorth(lastMousePos.x, lastMousePos.y);
417
418        // primitives under cursor are stored in c collection
419
420        OsmPrimitive nearestPrimitive = mv.getNearestNodeOrWay(e.getPoint(), mv.isSelectablePredicate, true);
421
422        determineMapMode(nearestPrimitive != null);
423
424        switch(mode) {
425        case ROTATE:
426        case SCALE:
427            //  if nothing was selected, select primitive under cursor for scaling or rotating
428            DataSet ds = getLayerManager().getEditDataSet();
429            if (ds.selectionEmpty()) {
430                ds.setSelected(asColl(nearestPrimitive));
431            }
432
433            // Mode.select redraws when selectPrims is called
434            // Mode.move   redraws when mouseDragged is called
435            // Mode.rotate redraws here
436            // Mode.scale redraws here
437            break;
438        case MOVE:
439            // also include case when some primitive is under cursor and no shift+ctrl / alt+ctrl is pressed
440            // so this is not movement, but selection on primitive under cursor
441            if (!cancelDrawMode && nearestPrimitive instanceof Way) {
442                virtualManager.activateVirtualNodeNearPoint(e.getPoint());
443            }
444            OsmPrimitive toSelect = cycleManager.cycleSetup(nearestPrimitive, e.getPoint());
445            selectPrims(asColl(toSelect), false, false);
446            useLastMoveCommandIfPossible();
447            // Schedule a timer to update status line "initialMoveDelay+1" ms in the future
448            GuiHelper.scheduleTimer(initialMoveDelay+1, evt -> updateStatusLine(), false);
449            break;
450        case SELECT:
451        default:
452            if (!(ctrl && PlatformManager.isPlatformOsx())) {
453                // start working with rectangle or lasso
454                selectionManager.register(mv, lassoMode);
455                selectionManager.mousePressed(e);
456                break;
457            }
458        }
459        if (giveUserFeedback(e)) {
460            mv.repaint();
461        }
462        updateStatusLine();
463    }
464
465    @Override
466    public void mouseMoved(MouseEvent e) {
467        // Mac OSX simulates with ctrl + mouse 1 the second mouse button hence no dragging events get fired.
468        if (PlatformManager.isPlatformOsx() && (mode == Mode.ROTATE || mode == Mode.SCALE)) {
469            mouseDragged(e);
470            return;
471        }
472        oldEvent = e;
473        if (giveUserFeedback(e)) {
474            mv.repaint();
475        }
476    }
477
478    /**
479     * If the left mouse button is pressed, move all currently selected
480     * objects (if one of them is under the mouse) or the current one under the
481     * mouse (which will become selected).
482     */
483    @Override
484    public void mouseDragged(MouseEvent e) {
485        if (!mv.isActiveLayerVisible())
486            return;
487
488        // Swing sends random mouseDragged events when closing dialogs by double-clicking their top-left icon on Windows
489        // Ignore such false events to prevent issues like #7078
490        if (mouseDownButton == MouseEvent.BUTTON1 && mouseReleaseTime > mouseDownTime)
491            return;
492
493        cancelDrawMode = true;
494        if (mode == Mode.SELECT) {
495            // Unregisters selectionManager if ctrl has been pressed after mouse click on Mac OS X in order to move the map
496            if (ctrl && PlatformManager.isPlatformOsx()) {
497                selectionManager.unregister(mv);
498                // Make sure correct cursor is displayed
499                mv.setNewCursor(Cursor.MOVE_CURSOR, this);
500            }
501            return;
502        }
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 && (e.getModifiersEx() & MouseEvent.BUTTON1_DOWN_MASK) == 0) {
509            // button is pressed in rotate mode
510            return;
511        }
512
513        if (mode == Mode.MOVE) {
514            // If ctrl is pressed we are in merge mode. Look for a nearby node,
515            // highlight it and adjust the cursor accordingly.
516            final boolean canMerge = ctrl && !getLayerManager().getEditDataSet().getSelectedNodes().isEmpty();
517            final OsmPrimitive p = canMerge ? findNodeToMergeTo(e.getPoint()) : null;
518            boolean needsRepaint = removeHighlighting();
519            if (p != null) {
520                p.setHighlighted(true);
521                currentHighlight = Optional.of(p);
522                needsRepaint = true;
523            }
524            mv.setNewCursor(getCursor(p), this);
525            // also update the stored mouse event, so we can display the correct cursor
526            // when dragging a node onto another one and then press CTRL to merge
527            oldEvent = e;
528            if (needsRepaint) {
529                mv.repaint();
530            }
531        }
532
533        if (startingDraggingPos == null) {
534            startingDraggingPos = new Point(e.getX(), e.getY());
535        }
536
537        if (lastMousePos == null) {
538            lastMousePos = e.getPoint();
539            return;
540        }
541
542        if (!initialMoveThresholdExceeded) {
543            int dp = (int) lastMousePos.distance(e.getX(), e.getY());
544            if (dp < initialMoveThreshold)
545                return; // ignore small drags
546            initialMoveThresholdExceeded = true; //no more ignoring until next mouse press
547        }
548        if (e.getPoint().equals(lastMousePos))
549            return;
550
551        EastNorth currentEN = mv.getEastNorth(e.getX(), e.getY());
552
553        if (virtualManager.hasVirtualWaysToBeConstructed()) {
554            virtualManager.createMiddleNodeFromVirtual(currentEN);
555        } else {
556            if (!updateCommandWhileDragging(currentEN)) return;
557        }
558
559        mv.repaint();
560        if (mode != Mode.SCALE) {
561            lastMousePos = e.getPoint();
562        }
563
564        didMouseDrag = true;
565    }
566
567    @Override
568    public void mouseExited(MouseEvent e) {
569        if (removeHighlighting()) {
570            mv.repaint();
571        }
572    }
573
574    @Override
575    public void mouseReleased(MouseEvent e) {
576        if (!mv.isActiveLayerVisible())
577            return;
578
579        startingDraggingPos = null;
580        mouseReleaseTime = System.currentTimeMillis();
581        MapFrame map = MainApplication.getMap();
582
583        if (mode == Mode.SELECT) {
584            if (e.getButton() != MouseEvent.BUTTON1) {
585                return;
586            }
587            selectionManager.endSelecting(e);
588            selectionManager.unregister(mv);
589
590            // Select Draw Tool if no selection has been made
591            if (!cancelDrawMode && getLayerManager().getActiveDataSet().selectionEmpty()) {
592                map.selectDrawTool(true);
593                updateStatusLine();
594                return;
595            }
596        }
597
598        if (mode == Mode.MOVE && e.getButton() == MouseEvent.BUTTON1) {
599            DataSet ds = getLayerManager().getEditDataSet();
600            if (!didMouseDrag) {
601                // only built in move mode
602                virtualManager.clear();
603                // do nothing if the click was to short too be recognized as a drag,
604                // but the release position is farther than 10px away from the press position
605                if (lastMousePos == null || lastMousePos.distanceSq(e.getPoint()) < 100) {
606                    updateKeyModifiers(e);
607                    selectPrims(cycleManager.cyclePrims(), true, false);
608
609                    // If the user double-clicked a node, change to draw mode
610                    Collection<OsmPrimitive> c = ds.getSelected();
611                    if (e.getClickCount() >= 2 && c.size() == 1 && c.iterator().next() instanceof Node) {
612                        // We need to do it like this as otherwise drawAction will see a double
613                        // click and switch back to SelectMode
614                        MainApplication.worker.execute(() -> map.selectDrawTool(true));
615                        return;
616                    }
617                }
618            } else {
619                confirmOrUndoMovement(e);
620            }
621        }
622
623        mode = null;
624
625        // simply remove any highlights if the middle click popup is active because
626        // the highlights don't depend on the cursor position there. If something was
627        // selected beforehand this would put us into move mode as well, which breaks
628        // the cycling through primitives on top of each other (see #6739).
629        if (e.getButton() == MouseEvent.BUTTON2) {
630            removeHighlighting();
631        } else {
632            giveUserFeedback(e);
633        }
634        updateStatusLine();
635    }
636
637    @Override
638    public void selectionEnded(Rectangle r, MouseEvent e) {
639        updateKeyModifiers(e);
640        selectPrims(selectionManager.getSelectedObjects(alt), true, true);
641    }
642
643    @Override
644    public void doKeyPressed(KeyEvent e) {
645        if (!repeatedKeySwitchLassoOption || !MainApplication.isDisplayingMapView() || !getShortcut().isEvent(e))
646            return;
647        if (Logging.isDebugEnabled()) {
648            Logging.debug("{0} consuming event {1}", getClass().getName(), e);
649        }
650        e.consume();
651        MapFrame map = MainApplication.getMap();
652        if (!lassoMode) {
653            map.selectMapMode(map.mapModeSelectLasso);
654        } else {
655            map.selectMapMode(map.mapModeSelect);
656        }
657    }
658
659    @Override
660    public void doKeyReleased(KeyEvent e) {
661        // Do nothing
662    }
663
664    /**
665     * sets the mapmode according to key modifiers and if there are any
666     * selectables nearby. Everything has to be pre-determined for this
667     * function; its main purpose is to centralize what the modifiers do.
668     * @param hasSelectionNearby {@code true} if some primitves are selectable nearby
669     */
670    private void determineMapMode(boolean hasSelectionNearby) {
671        if (getLayerManager().getEditDataSet() != null) {
672            if (shift && ctrl) {
673                mode = Mode.ROTATE;
674            } else if (alt && ctrl) {
675                mode = Mode.SCALE;
676            } else if (hasSelectionNearby || dragInProgress()) {
677                mode = Mode.MOVE;
678            } else {
679                mode = Mode.SELECT;
680            }
681        } else {
682            mode = Mode.SELECT;
683        }
684    }
685
686    /**
687     * Determines whenever elements have been grabbed and moved (i.e. the initial
688     * thresholds have been exceeded) and is still in progress (i.e. mouse button still pressed)
689     * @return true if a drag is in progress
690     */
691    private boolean dragInProgress() {
692        return didMouseDrag && startingDraggingPos != null;
693    }
694
695    /**
696     * Create or update data modification command while dragging mouse - implementation of
697     * continuous moving, scaling and rotation
698     * @param currentEN - mouse position
699     * @return status of action (<code>true</code> when action was performed)
700     */
701    private boolean updateCommandWhileDragging(EastNorth currentEN) {
702        // Currently we support only transformations which do not affect relations.
703        // So don't add them in the first place to make handling easier
704        DataSet ds = getLayerManager().getEditDataSet();
705        Collection<OsmPrimitive> selection = ds.getSelectedNodesAndWays();
706        if (selection.isEmpty()) { // if nothing was selected to drag, just select nearest node/way to the cursor
707            ds.setSelected(mv.getNearestNodeOrWay(mv.getPoint(startEN), mv.isSelectablePredicate, true));
708        }
709
710        Collection<Node> affectedNodes = AllNodesVisitor.getAllNodes(selection);
711        // for these transformations, having only one node makes no sense - quit silently
712        if (affectedNodes.size() < 2 && (mode == Mode.ROTATE || mode == Mode.SCALE)) {
713            return false;
714        }
715        Command c = getLastCommandInDataset(ds);
716        if (mode == Mode.MOVE) {
717            if (startEN == null) return false; // fix #8128
718            return ds.update(() -> {
719                MoveCommand moveCmd = null;
720                if (c instanceof MoveCommand && affectedNodes.equals(((MoveCommand) c).getParticipatingPrimitives())) {
721                    moveCmd = (MoveCommand) c;
722                    moveCmd.saveCheckpoint();
723                    moveCmd.applyVectorTo(currentEN);
724                } else if (!selection.isEmpty()) {
725                    moveCmd = new MoveCommand(selection, startEN, currentEN);
726                    UndoRedoHandler.getInstance().add(moveCmd);
727                }
728                for (Node n : affectedNodes) {
729                    if (n.isOutSideWorld()) {
730                        // Revert move
731                        if (moveCmd != null) {
732                            moveCmd.resetToCheckpoint();
733                        }
734                        // TODO: We might use a simple notification in the lower left corner.
735                        JOptionPane.showMessageDialog(
736                                MainApplication.getMainFrame(),
737                                tr("Cannot move objects outside of the world."),
738                                tr("Warning"),
739                                JOptionPane.WARNING_MESSAGE);
740                        mv.setNewCursor(cursor, this);
741                        return false;
742                    }
743                }
744                return true;
745            });
746        } else {
747            startEN = currentEN; // drag can continue after scaling/rotation
748
749            if (mode != Mode.ROTATE && mode != Mode.SCALE) {
750                return false;
751            }
752
753            return ds.update(() -> {
754                if (mode == Mode.ROTATE) {
755                    if (c instanceof RotateCommand && affectedNodes.equals(((RotateCommand) c).getTransformedNodes())) {
756                        ((RotateCommand) c).handleEvent(currentEN);
757                    } else {
758                        UndoRedoHandler.getInstance().add(new RotateCommand(selection, currentEN));
759                    }
760                } else if (mode == Mode.SCALE) {
761                    if (c instanceof ScaleCommand && affectedNodes.equals(((ScaleCommand) c).getTransformedNodes())) {
762                        ((ScaleCommand) c).handleEvent(currentEN);
763                    } else {
764                        UndoRedoHandler.getInstance().add(new ScaleCommand(selection, currentEN));
765                    }
766                }
767
768                Collection<Way> ways = ds.getSelectedWays();
769                if (doesImpactStatusLine(affectedNodes, ways)) {
770                    MainApplication.getMap().statusLine.setDist(ways);
771                }
772                if (c instanceof RotateCommand) {
773                    double angle = Utils.toDegrees(((RotateCommand) c).getRotationAngle());
774                    MainApplication.getMap().statusLine.setAngleNaN(angle);
775                } else if (c instanceof ScaleCommand) {
776                    // U+00D7 MULTIPLICATION SIGN
777                    String angle = String.format("%.2f", ((ScaleCommand) c).getScalingFactor()) + " \u00d7";
778                    MainApplication.getMap().statusLine.setAngleText(angle);
779                }
780                return true;
781            });
782        }
783    }
784
785    private static boolean doesImpactStatusLine(Collection<Node> affectedNodes, Collection<Way> selectedWays) {
786        return selectedWays.stream()
787                .flatMap(w -> w.getNodes().stream())
788                .anyMatch(affectedNodes::contains);
789    }
790
791    /**
792     * Adapt last move command (if it is suitable) to work with next drag, started at point startEN
793     */
794    private void useLastMoveCommandIfPossible() {
795        DataSet dataSet = getLayerManager().getEditDataSet();
796        if (dataSet == null) {
797            // It may happen that there is no edit layer.
798            return;
799        }
800        Command c = getLastCommandInDataset(dataSet);
801        Collection<Node> affectedNodes = AllNodesVisitor.getAllNodes(dataSet.getSelected());
802        if (c instanceof MoveCommand && affectedNodes.equals(((MoveCommand) c).getParticipatingPrimitives())) {
803            // old command was created with different base point of movement, we need to recalculate it
804            ((MoveCommand) c).changeStartPoint(startEN);
805        }
806    }
807
808    /**
809     * Obtain command in undoRedo stack to "continue" when dragging
810     * @param ds The data set the command needs to be in.
811     * @return last command
812     */
813    private static Command getLastCommandInDataset(DataSet ds) {
814        Command lastCommand = UndoRedoHandler.getInstance().getLastCommand();
815        if (lastCommand instanceof SequenceCommand) {
816            lastCommand = ((SequenceCommand) lastCommand).getLastCommand();
817        }
818        if (lastCommand != null && ds.equals(lastCommand.getAffectedDataSet())) {
819            return lastCommand;
820        } else {
821            return null;
822        }
823    }
824
825    /**
826     * Present warning in the following cases and undo unwanted movements: <ul>
827     * <li>large and possibly unwanted movements</li>
828     * <li>movement of node with attached ways that are hidden by filters</li>
829     * </ul>
830     *
831     * @param e the mouse event causing the action (mouse released)
832     */
833    private void confirmOrUndoMovement(MouseEvent e) {
834        if (movesHiddenWay()) {
835            final ConfirmMoveDialog ed = new ConfirmMoveDialog();
836            ed.setContent(tr("Are you sure that you want to move elements with attached ways that are hidden by filters?"));
837            ed.toggleEnable("movedHiddenElements");
838            showConfirmMoveDialog(ed);
839        }
840
841        final Command lastCommand = UndoRedoHandler.getInstance().getLastCommand();
842        if (lastCommand == null) {
843            Logging.warn("No command found in undo/redo history, skipping confirmOrUndoMovement");
844            return;
845        }
846
847        SelectAction.checkCommandForLargeDistance(lastCommand);
848
849        final int moveCount = lastCommand.getParticipatingPrimitives().size();
850        final int max = Config.getPref().getInt("warn.move.maxelements", 20);
851        if (moveCount > max) {
852            final ConfirmMoveDialog ed = new ConfirmMoveDialog();
853            ed.setContent(
854                    /* for correct i18n of plural forms - see #9110 */
855                    trn("You moved more than {0} element. " + "Moving a large number of elements is often an error.\n" + "Really move them?",
856                        "You moved more than {0} elements. " + "Moving a large number of elements is often an error.\n" + "Really move them?",
857                        max, max));
858            ed.toggleEnable("movedManyElements");
859            showConfirmMoveDialog(ed);
860        } else {
861            // if small number of elements were moved,
862            updateKeyModifiers(e);
863            if (ctrl) mergePrims(e.getPoint());
864        }
865    }
866
867    static void checkCommandForLargeDistance(Command lastCommand) {
868        final int moveCount = lastCommand.getParticipatingPrimitives().size();
869        if (lastCommand instanceof MoveCommand) {
870            final double moveDistance = ((MoveCommand) lastCommand).getDistance(n -> !n.isNew());
871            if (Double.isFinite(moveDistance) && moveDistance > Config.getPref().getInt("warn.move.maxdistance", 200)) {
872                final ConfirmMoveDialog ed = new ConfirmMoveDialog();
873                ed.setContent(trn(
874                        "You moved {0} element by a distance of {1}. "
875                                + "Moving elements by a large distance is often an error.\n" + "Really move them?",
876                        "You moved {0} elements by a distance of {1}. "
877                                + "Moving elements by a large distance is often an error.\n" + "Really move them?",
878                        moveCount, moveCount, SystemOfMeasurement.getSystemOfMeasurement().getDistText(moveDistance)));
879                ed.toggleEnable("movedLargeDistance");
880                showConfirmMoveDialog(ed);
881            }
882        }
883    }
884
885    private static void showConfirmMoveDialog(ConfirmMoveDialog ed) {
886        if (ed.showDialog().getValue() != 1) {
887            UndoRedoHandler.getInstance().undo();
888        }
889    }
890
891    static class ConfirmMoveDialog extends ExtendedDialog {
892        ConfirmMoveDialog() {
893            super(MainApplication.getMainFrame(),
894                    tr("Move elements"),
895                    tr("Move them"), tr("Undo move"));
896            setButtonIcons("reorder", "cancel");
897            setCancelButton(2);
898        }
899    }
900
901    private boolean movesHiddenWay() {
902        DataSet ds = getLayerManager().getEditDataSet();
903        final Collection<Node> elementsToTest = new HashSet<>(ds.getSelectedNodes());
904        for (Way osm : ds.getSelectedWays()) {
905            elementsToTest.addAll(osm.getNodes());
906        }
907        return elementsToTest.stream()
908                .flatMap(n -> n.referrers(Way.class))
909                .anyMatch(Way::isDisabledAndHidden);
910    }
911
912    /**
913     * Merges the selected nodes to the one closest to the given mouse position if the control
914     * key is pressed. If there is no such node, no action will be done and no error will be
915     * reported. If there is, it will execute the merge and add it to the undo buffer.
916     * @param p mouse position
917     */
918    private void mergePrims(Point p) {
919        DataSet ds = getLayerManager().getEditDataSet();
920        Collection<Node> selNodes = ds.getSelectedNodes();
921        if (selNodes.isEmpty())
922            return;
923
924        Node target = findNodeToMergeTo(p);
925        if (target == null)
926            return;
927
928        if (selNodes.size() == 1) {
929            // Move all selected primitive to preserve shape #10748
930            Collection<OsmPrimitive> selection = ds.getSelectedNodesAndWays();
931            Collection<Node> affectedNodes = AllNodesVisitor.getAllNodes(selection);
932            Command c = getLastCommandInDataset(ds);
933            ds.update(() -> {
934                if (c instanceof MoveCommand && affectedNodes.equals(((MoveCommand) c).getParticipatingPrimitives())) {
935                    Node selectedNode = selNodes.iterator().next();
936                    EastNorth selectedEN = selectedNode.getEastNorth();
937                    EastNorth targetEN = target.getEastNorth();
938                    ((MoveCommand) c).moveAgain(targetEN.getX() - selectedEN.getX(),
939                                                targetEN.getY() - selectedEN.getY());
940                }
941            });
942        }
943
944        Collection<Node> nodesToMerge = new LinkedList<>(selNodes);
945        nodesToMerge.add(target);
946        mergeNodes(MainApplication.getLayerManager().getEditLayer(), nodesToMerge, target);
947    }
948
949    /**
950     * Merge nodes using {@code MergeNodesAction}.
951     * Can be overridden for testing purpose.
952     * @param layer layer the reference data layer. Must not be null
953     * @param nodes the collection of nodes. Ignored if null
954     * @param targetLocationNode this node's location will be used for the target node
955     */
956    public void mergeNodes(OsmDataLayer layer, Collection<Node> nodes,
957                           Node targetLocationNode) {
958        MergeNodesAction.doMergeNodes(layer, nodes, targetLocationNode);
959    }
960
961    /**
962     * Tries to find a node to merge to when in move-merge mode for the current mouse
963     * position. Either returns the node or null, if no suitable one is nearby.
964     * @param p mouse position
965     * @return node to merge to, or null
966     */
967    private Node findNodeToMergeTo(Point p) {
968        Collection<Node> target = mv.getNearestNodes(p,
969                getLayerManager().getEditDataSet().getSelectedNodes(),
970                mv.isSelectablePredicate);
971        return target.isEmpty() ? null : target.iterator().next();
972    }
973
974    private void selectPrims(Collection<OsmPrimitive> prims, boolean released, boolean area) {
975        DataSet ds = getLayerManager().getActiveDataSet();
976
977        // not allowed together: do not change dataset selection, return early
978        // Virtual Ways: if non-empty the cursor is above a virtual node. So don't highlight
979        // anything if about to drag the virtual node (i.e. !released) but continue if the
980        // cursor is only released above a virtual node by accident (i.e. released). See #7018
981        if (ds == null || (shift && ctrl) || (ctrl && !released) || (virtualManager.hasVirtualWaysToBeConstructed() && !released))
982            return;
983
984        if (!released) {
985            // Don't replace the selection if the user clicked on a
986            // selected object (it breaks moving of selected groups).
987            // Do it later, on mouse release.
988            shift |= ds.getSelected().containsAll(prims);
989        }
990
991        if (ctrl) {
992            // Ctrl on an item toggles its selection status,
993            // but Ctrl on an *area* just clears those items
994            // out of the selection.
995            if (area) {
996                ds.clearSelection(prims);
997            } else {
998                ds.toggleSelected(prims);
999            }
1000        } else if (shift) {
1001            // add prims to an existing selection
1002            ds.addSelected(prims);
1003        } else {
1004            // clear selection, then select the prims clicked
1005            ds.setSelected(prims);
1006        }
1007    }
1008
1009    /**
1010     * Returns the current select mode.
1011     * @return the select mode
1012     * @since 7543
1013     */
1014    public final Mode getMode() {
1015        return mode;
1016    }
1017
1018    @Override
1019    public String getModeHelpText() {
1020        if (mouseDownButton == MouseEvent.BUTTON1 && mouseReleaseTime < mouseDownTime) {
1021            if (mode == Mode.SELECT)
1022                return tr("Release the mouse button to select the objects in the rectangle.");
1023            else if (mode == Mode.MOVE && (System.currentTimeMillis() - mouseDownTime >= initialMoveDelay)) {
1024                final DataSet ds = getLayerManager().getEditDataSet();
1025                final boolean canMerge = ds != null && !ds.getSelectedNodes().isEmpty();
1026                final String mergeHelp = canMerge ? (' ' + tr("Ctrl to merge with nearest node.")) : "";
1027                return tr("Release the mouse button to stop moving.") + mergeHelp;
1028            } else if (mode == Mode.ROTATE)
1029                return tr("Release the mouse button to stop rotating.");
1030            else if (mode == Mode.SCALE)
1031                return tr("Release the mouse button to stop scaling.");
1032        }
1033        return tr("Move objects by dragging; Shift to add to selection (Ctrl to toggle); Shift-Ctrl to rotate selected; " +
1034                  "Alt-Ctrl to scale selected; or change selection");
1035    }
1036
1037    @Override
1038    public boolean layerIsSupported(Layer l) {
1039        return l instanceof OsmDataLayer;
1040    }
1041
1042    /**
1043     * Enable or diable the lasso mode
1044     * @param lassoMode true to enable the lasso mode, false otherwise
1045     */
1046    public void setLassoMode(boolean lassoMode) {
1047        this.selectionManager.setLassoMode(lassoMode);
1048        this.lassoMode = lassoMode;
1049    }
1050
1051    private final transient CycleManager cycleManager = new CycleManager();
1052    private final transient VirtualManager virtualManager = new VirtualManager();
1053
1054    private class CycleManager {
1055
1056        private Collection<OsmPrimitive> cycleList = Collections.emptyList();
1057        private boolean cyclePrims;
1058        private OsmPrimitive cycleStart;
1059        private boolean waitForMouseUpParameter;
1060        private boolean multipleMatchesParameter;
1061        /**
1062         * read preferences
1063         */
1064        private void init() {
1065            waitForMouseUpParameter = Config.getPref().getBoolean("mappaint.select.waits-for-mouse-up", false);
1066            multipleMatchesParameter = Config.getPref().getBoolean("selectaction.cycles.multiple.matches", false);
1067        }
1068
1069        /**
1070         * Determine primitive to be selected and build cycleList
1071         * @param nearest primitive found by simple method
1072         * @param p point where user clicked
1073         * @return OsmPrimitive to be selected
1074         */
1075        private OsmPrimitive cycleSetup(OsmPrimitive nearest, Point p) {
1076            OsmPrimitive osm = null;
1077
1078            if (nearest != null) {
1079                osm = nearest;
1080
1081                if (!(alt || multipleMatchesParameter)) {
1082                    // no real cycling, just one element in cycle list
1083                    cycleList = asColl(osm);
1084
1085                    if (waitForMouseUpParameter) {
1086                        // prefer a selected nearest node or way, if possible
1087                        osm = mv.getNearestNodeOrWay(p, mv.isSelectablePredicate, true);
1088                    }
1089                } else {
1090                    // Alt + left mouse button pressed: we need to build cycle list
1091                    cycleList = mv.getAllNearest(p, mv.isSelectablePredicate);
1092
1093                    if (cycleList.size() > 1) {
1094                        cyclePrims = false;
1095
1096                        // find first already selected element in cycle list
1097                        OsmPrimitive old = osm;
1098                        for (OsmPrimitive o : cycleList) {
1099                            if (o.isSelected()) {
1100                                cyclePrims = true;
1101                                osm = o;
1102                                break;
1103                            }
1104                        }
1105
1106                        // special case:  for cycle groups of 2, we can toggle to the
1107                        // true nearest primitive on mousePressed right away
1108                        if (cycleList.size() == 2 && !waitForMouseUpParameter) {
1109                            if (!(osm.equals(old) || osm.isNew() || ctrl)) {
1110                                cyclePrims = false;
1111                                osm = old;
1112                            } // else defer toggling to mouseRelease time in those cases:
1113                            /*
1114                             * osm == old -- the true nearest node is the
1115                             * selected one osm is a new node -- do not break
1116                             * unglue ways in ALT mode ctrl is pressed -- ctrl
1117                             * generally works on mouseReleased
1118                             */
1119                        }
1120                    }
1121                }
1122            }
1123            return osm;
1124        }
1125
1126        /**
1127         * Modifies current selection state and returns the next element in a
1128         * selection cycle given by
1129         * <code>cycleList</code> field
1130         * @return the next element of cycle list
1131         */
1132        private Collection<OsmPrimitive> cyclePrims() {
1133            if (cycleList.size() <= 1) {
1134                // no real cycling, just return one-element collection with nearest primitive in it
1135                return cycleList;
1136            }
1137            // updateKeyModifiers() already called before!
1138
1139            DataSet ds = getLayerManager().getActiveDataSet();
1140            OsmPrimitive first = cycleList.iterator().next(), foundInDS = null;
1141            OsmPrimitive nxt = first;
1142
1143            if (cyclePrims && shift) {
1144                for (OsmPrimitive osmPrimitive : cycleList) {
1145                    nxt = osmPrimitive;
1146                    if (!nxt.isSelected()) {
1147                        break; // take first primitive in cycleList not in sel
1148                    }
1149                }
1150                // if primitives 1,2,3 are under cursor, [Alt-press] [Shift-release] gives 1 -> 12 -> 123
1151            } else {
1152                for (Iterator<OsmPrimitive> i = cycleList.iterator(); i.hasNext();) {
1153                    nxt = i.next();
1154                    if (nxt.isSelected()) {
1155                        foundInDS = nxt;
1156                        // first selected primitive in cycleList is found
1157                        if (cyclePrims || ctrl) {
1158                            ds.clearSelection(foundInDS); // deselect it
1159                            nxt = i.hasNext() ? i.next() : first;
1160                            // return next one in cycle list (last->first)
1161                        }
1162                        break; // take next primitive in cycleList
1163                    }
1164                }
1165            }
1166
1167            // if "no-alt-cycling" is enabled, Ctrl-Click arrives here.
1168            if (ctrl) {
1169                // a member of cycleList was found in the current dataset selection
1170                if (foundInDS != null) {
1171                    // mouse was moved to a different selection group w/ a previous sel
1172                    if (!cycleList.contains(cycleStart)) {
1173                        ds.clearSelection(cycleList);
1174                        cycleStart = foundInDS;
1175                    } else if (cycleStart.equals(nxt)) {
1176                        // loop detected, insert deselect step
1177                        ds.addSelected(nxt);
1178                    }
1179                } else {
1180                    // setup for iterating a sel group again or a new, different one..
1181                    nxt = cycleList.contains(cycleStart) ? cycleStart : first;
1182                    cycleStart = nxt;
1183                }
1184            } else {
1185                cycleStart = null;
1186            }
1187            // return one-element collection with one element to be selected (or added  to selection)
1188            return asColl(nxt);
1189        }
1190    }
1191
1192    private class VirtualManager {
1193
1194        private Node virtualNode;
1195        private Collection<WaySegment> virtualWays = new LinkedList<>();
1196        private int nodeVirtualSize;
1197        private int virtualSnapDistSq2;
1198        private int virtualSpace;
1199
1200        private void init() {
1201            nodeVirtualSize = Config.getPref().getInt("mappaint.node.virtual-size", 8);
1202            int virtualSnapDistSq = Config.getPref().getInt("mappaint.node.virtual-snap-distance", 8);
1203            virtualSnapDistSq2 = virtualSnapDistSq*virtualSnapDistSq;
1204            virtualSpace = Config.getPref().getInt("mappaint.node.virtual-space", 70);
1205        }
1206
1207        /**
1208         * Calculate a virtual node if there is enough visual space to draw a
1209         * crosshair node and the middle of a way segment is clicked. If the
1210         * user drags the crosshair node, it will be added to all ways in
1211         * <code>virtualWays</code>.
1212         *
1213         * @param p the point clicked
1214         * @return whether
1215         * <code>virtualNode</code> and
1216         * <code>virtualWays</code> were setup.
1217         */
1218        private boolean activateVirtualNodeNearPoint(Point p) {
1219            if (nodeVirtualSize > 0) {
1220
1221                Collection<WaySegment> selVirtualWays = new LinkedList<>();
1222                Pair<Node, Node> vnp = null, wnp = new Pair<>(null, null);
1223
1224                for (WaySegment ws : mv.getNearestWaySegments(p, mv.isSelectablePredicate)) {
1225                    Way w = ws.getWay();
1226
1227                    wnp.a = w.getNode(ws.getLowerIndex());
1228                    wnp.b = w.getNode(ws.getUpperIndex());
1229                    MapViewPoint p1 = mv.getState().getPointFor(wnp.a);
1230                    MapViewPoint p2 = mv.getState().getPointFor(wnp.b);
1231                    if (WireframeMapRenderer.isLargeSegment(p1, p2, virtualSpace)) {
1232                        Point2D pc = new Point2D.Double((p1.getInViewX() + p2.getInViewX()) / 2, (p1.getInViewY() + p2.getInViewY()) / 2);
1233                        if (p.distanceSq(pc) < virtualSnapDistSq2) {
1234                            // Check that only segments on top of each other get added to the
1235                            // virtual ways list. Otherwise ways that coincidentally have their
1236                            // virtual node at the same spot will be joined which is likely unwanted
1237                            Pair.sort(wnp);
1238                            if (vnp == null) {
1239                                vnp = new Pair<>(wnp.a, wnp.b);
1240                                virtualNode = new Node(mv.getLatLon(pc.getX(), pc.getY()));
1241                            }
1242                            if (vnp.equals(wnp)) {
1243                                // if mutiple line segments have the same points,
1244                                // add all segments to be splitted to virtualWays list
1245                                // if some lines are selected, only their segments will go to virtualWays
1246                                (w.isSelected() ? selVirtualWays : virtualWays).add(ws);
1247                            }
1248                        }
1249                    }
1250                }
1251
1252                if (!selVirtualWays.isEmpty()) {
1253                    virtualWays = selVirtualWays;
1254                }
1255            }
1256
1257            return !virtualWays.isEmpty();
1258        }
1259
1260        private void createMiddleNodeFromVirtual(EastNorth currentEN) {
1261            if (startEN == null) // #13724, #14712, #15087
1262                return;
1263            DataSet ds = getLayerManager().getEditDataSet();
1264            Collection<Command> virtualCmds = new LinkedList<>();
1265            virtualCmds.add(new AddCommand(ds, virtualNode));
1266            for (WaySegment virtualWay : virtualWays) {
1267                Way w = virtualWay.getWay();
1268                List<Node> modNodes = w.getNodes();
1269                modNodes.add(virtualWay.getUpperIndex(), virtualNode);
1270                virtualCmds.add(new ChangeNodesCommand(ds, w, modNodes));
1271            }
1272            virtualCmds.add(new MoveCommand(ds, virtualNode, startEN, currentEN));
1273            String text = trn("Add and move a virtual new node to way",
1274                    "Add and move a virtual new node to {0} ways", virtualWays.size(),
1275                    virtualWays.size());
1276            UndoRedoHandler.getInstance().add(new SequenceCommand(text, virtualCmds));
1277            ds.setSelected(Collections.singleton((OsmPrimitive) virtualNode));
1278            clear();
1279        }
1280
1281        private void clear() {
1282            virtualWays.clear();
1283            virtualNode = null;
1284        }
1285
1286        private boolean hasVirtualNode() {
1287            return virtualNode != null;
1288        }
1289
1290        private boolean hasVirtualWaysToBeConstructed() {
1291            return !virtualWays.isEmpty();
1292        }
1293    }
1294
1295    /**
1296     * Returns {@code o} as collection of {@code o}'s type.
1297     * @param <T> object type
1298     * @param o any object
1299     * @return {@code o} as collection of {@code o}'s type.
1300     */
1301    protected static <T> Collection<T> asColl(T o) {
1302        return o == null ? Collections.emptySet() : Collections.singleton(o);
1303    }
1304}