001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.actions;
003
004import static org.openstreetmap.josm.tools.I18n.marktr;
005import static org.openstreetmap.josm.tools.I18n.tr;
006import static org.openstreetmap.josm.tools.I18n.trn;
007
008import java.awt.event.ActionEvent;
009import java.awt.event.KeyEvent;
010import java.util.ArrayList;
011import java.util.Collection;
012import java.util.Collections;
013import java.util.HashMap;
014import java.util.HashSet;
015import java.util.LinkedHashSet;
016import java.util.LinkedList;
017import java.util.List;
018import java.util.Map;
019import java.util.Set;
020import java.util.TreeMap;
021
022import javax.swing.JOptionPane;
023
024import org.openstreetmap.josm.Main;
025import org.openstreetmap.josm.actions.ReverseWayAction.ReverseWayResult;
026import org.openstreetmap.josm.actions.SplitWayAction.SplitWayResult;
027import org.openstreetmap.josm.command.AddCommand;
028import org.openstreetmap.josm.command.ChangeCommand;
029import org.openstreetmap.josm.command.Command;
030import org.openstreetmap.josm.command.DeleteCommand;
031import org.openstreetmap.josm.command.SequenceCommand;
032import org.openstreetmap.josm.corrector.UserCancelException;
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.NodePositionComparator;
038import org.openstreetmap.josm.data.osm.OsmPrimitive;
039import org.openstreetmap.josm.data.osm.Relation;
040import org.openstreetmap.josm.data.osm.RelationMember;
041import org.openstreetmap.josm.data.osm.TagCollection;
042import org.openstreetmap.josm.data.osm.Way;
043import org.openstreetmap.josm.gui.Notification;
044import org.openstreetmap.josm.gui.conflict.tags.CombinePrimitiveResolverDialog;
045import org.openstreetmap.josm.tools.Geometry;
046import org.openstreetmap.josm.tools.Pair;
047import org.openstreetmap.josm.tools.Shortcut;
048
049/**
050 * Join Areas (i.e. closed ways and multipolygons).
051 * @since 2575
052 */
053public class JoinAreasAction extends JosmAction {
054    // This will be used to commit commands and unite them into one large command sequence at the end
055    private final LinkedList<Command> cmds = new LinkedList<>();
056    private int cmdsCount = 0;
057    private final List<Relation> addedRelations = new LinkedList<>();
058
059    /**
060     * This helper class describes join areas action result.
061     * @author viesturs
062     */
063    public static class JoinAreasResult {
064
065        public boolean hasChanges;
066
067        public List<Multipolygon> polygons;
068    }
069
070    public static class Multipolygon {
071        public Way outerWay;
072        public List<Way> innerWays;
073
074        public Multipolygon(Way way) {
075            outerWay = way;
076            innerWays = new ArrayList<>();
077        }
078    }
079
080    // HelperClass
081    // Saves a relation and a role an OsmPrimitve was part of until it was stripped from all relations
082    private static class RelationRole {
083        public final Relation rel;
084        public final String role;
085        public RelationRole(Relation rel, String role) {
086            this.rel = rel;
087            this.role = role;
088        }
089
090        @Override
091        public int hashCode() {
092            return rel.hashCode();
093        }
094
095        @Override
096        public boolean equals(Object other) {
097            if (!(other instanceof RelationRole)) return false;
098            RelationRole otherMember = (RelationRole) other;
099            return otherMember.role.equals(role) && otherMember.rel.equals(rel);
100        }
101    }
102
103
104    /**
105     * HelperClass - saves a way and the "inside" side.
106     *
107     * insideToTheLeft: if true left side is "in", false -right side is "in".
108     * Left and right are determined along the orientation of way.
109     */
110    public static class WayInPolygon {
111        public final Way way;
112        public boolean insideToTheRight;
113
114        public WayInPolygon(Way way, boolean insideRight) {
115            this.way = way;
116            this.insideToTheRight = insideRight;
117        }
118
119        @Override
120        public int hashCode() {
121            return way.hashCode();
122        }
123
124        @Override
125        public boolean equals(Object other) {
126            if (!(other instanceof WayInPolygon)) return false;
127            WayInPolygon otherMember = (WayInPolygon) other;
128            return otherMember.way.equals(this.way) && otherMember.insideToTheRight == this.insideToTheRight;
129        }
130    }
131
132    /**
133     * This helper class describes a polygon, assembled from several ways.
134     * @author viesturs
135     *
136     */
137    public static class AssembledPolygon {
138        public List<WayInPolygon> ways;
139
140        public AssembledPolygon(List<WayInPolygon> boundary) {
141            this.ways = boundary;
142        }
143
144        public List<Node> getNodes() {
145            List<Node> nodes = new ArrayList<>();
146            for (WayInPolygon way : this.ways) {
147                //do not add the last node as it will be repeated in the next way
148                if (way.insideToTheRight) {
149                    for (int pos = 0; pos < way.way.getNodesCount() - 1; pos++) {
150                        nodes.add(way.way.getNode(pos));
151                    }
152                }
153                else {
154                    for (int pos = way.way.getNodesCount() - 1; pos > 0; pos--) {
155                        nodes.add(way.way.getNode(pos));
156                    }
157                }
158            }
159
160            return nodes;
161        }
162
163        /**
164         * Inverse inside and outside
165         */
166        public void reverse() {
167            for(WayInPolygon way: ways)
168                way.insideToTheRight = !way.insideToTheRight;
169            Collections.reverse(ways);
170        }
171    }
172
173    public static class AssembledMultipolygon {
174        public AssembledPolygon outerWay;
175        public List<AssembledPolygon> innerWays;
176
177        public AssembledMultipolygon(AssembledPolygon way) {
178            outerWay = way;
179            innerWays = new ArrayList<>();
180        }
181    }
182
183    /**
184     * This hepler class implements algorithm traversing trough connected ways.
185     * Assumes you are going in clockwise orientation.
186     * @author viesturs
187     */
188    private static class WayTraverser {
189
190        /** Set of {@link WayInPolygon} to be joined by walk algorithm */
191        private Set<WayInPolygon> availableWays;
192        /** Current state of walk algorithm */
193        private WayInPolygon lastWay;
194        /** Direction of current way */
195        private boolean lastWayReverse;
196
197        /** Constructor */
198        public WayTraverser(Collection<WayInPolygon> ways) {
199            availableWays = new HashSet<>(ways);
200            lastWay = null;
201        }
202
203        /**
204         *  Remove ways from available ways
205         *  @param ways Collection of WayInPolygon
206         */
207        public void removeWays(Collection<WayInPolygon> ways) {
208            availableWays.removeAll(ways);
209        }
210
211        /**
212         * Remove a single way from available ways
213         * @param way WayInPolygon
214         */
215        public void removeWay(WayInPolygon way) {
216            availableWays.remove(way);
217        }
218
219        /**
220         * Reset walk algorithm to a new start point
221         * @param way New start point
222         */
223        public void setStartWay(WayInPolygon way) {
224            lastWay = way;
225            lastWayReverse = !way.insideToTheRight;
226        }
227
228        /**
229         * Reset walk algorithm to a new start point.
230         * @return The new start point or null if no available way remains
231         */
232        public WayInPolygon startNewWay() {
233            if (availableWays.isEmpty()) {
234                lastWay = null;
235            } else {
236                lastWay = availableWays.iterator().next();
237                lastWayReverse = !lastWay.insideToTheRight;
238            }
239
240            return lastWay;
241        }
242
243        /**
244         * Walking through {@link WayInPolygon} segments, head node is the current position
245         * @return Head node
246         */
247        private Node getHeadNode() {
248            return !lastWayReverse ? lastWay.way.lastNode() : lastWay.way.firstNode();
249        }
250
251        /**
252         * Node just before head node.
253         * @return Previous node
254         */
255        private Node getPrevNode() {
256            return !lastWayReverse ? lastWay.way.getNode(lastWay.way.getNodesCount() - 2) : lastWay.way.getNode(1);
257        }
258
259        /**
260         * Oriented angle (N1N2, N1N3) in range [0; 2*Math.PI[
261         */
262        private static double getAngle(Node N1, Node N2, Node N3) {
263            EastNorth en1 = N1.getEastNorth();
264            EastNorth en2 = N2.getEastNorth();
265            EastNorth en3 = N3.getEastNorth();
266            double angle = Math.atan2(en3.getY() - en1.getY(), en3.getX() - en1.getX()) -
267                    Math.atan2(en2.getY() - en1.getY(), en2.getX() - en1.getX());
268            while(angle >= 2*Math.PI)
269                angle -= 2*Math.PI;
270            while(angle < 0)
271                angle += 2*Math.PI;
272            return angle;
273        }
274
275        /**
276         * Get the next way creating a clockwise path, ensure it is the most right way. #7959
277         * @return The next way.
278         */
279        public  WayInPolygon walk() {
280            Node headNode = getHeadNode();
281            Node prevNode = getPrevNode();
282
283            double headAngle = Math.atan2(headNode.getEastNorth().east() - prevNode.getEastNorth().east(),
284                    headNode.getEastNorth().north() - prevNode.getEastNorth().north());
285            double bestAngle = 0;
286
287            //find best next way
288            WayInPolygon bestWay = null;
289            boolean bestWayReverse = false;
290
291            for (WayInPolygon way : availableWays) {
292                Node nextNode;
293
294                // Check for a connected way
295                if (way.way.firstNode().equals(headNode) && way.insideToTheRight) {
296                    nextNode = way.way.getNode(1);
297                } else if (way.way.lastNode().equals(headNode) && !way.insideToTheRight) {
298                    nextNode = way.way.getNode(way.way.getNodesCount() - 2);
299                } else {
300                    continue;
301                }
302
303                if(nextNode == prevNode) {
304                    // go back
305                    lastWay = way;
306                    lastWayReverse = !way.insideToTheRight;
307                    return lastWay;
308                }
309
310                double angle = Math.atan2(nextNode.getEastNorth().east() - headNode.getEastNorth().east(),
311                        nextNode.getEastNorth().north() - headNode.getEastNorth().north()) - headAngle;
312                if(angle > Math.PI)
313                    angle -= 2*Math.PI;
314                if(angle <= -Math.PI)
315                    angle += 2*Math.PI;
316
317                // Now we have a valid candidate way, is it better than the previous one ?
318                if (bestWay == null || angle > bestAngle) {
319                    //the new way is better
320                    bestWay = way;
321                    bestWayReverse = !way.insideToTheRight;
322                    bestAngle = angle;
323                }
324            }
325
326            lastWay = bestWay;
327            lastWayReverse = bestWayReverse;
328            return lastWay;
329        }
330
331        /**
332         * Search for an other way coming to the same head node at left side from last way. #9951
333         * @return left way or null if none found
334         */
335        public WayInPolygon leftComingWay() {
336            Node headNode = getHeadNode();
337            Node prevNode = getPrevNode();
338
339            WayInPolygon mostLeft = null; // most left way connected to head node
340            boolean comingToHead = false; // true if candidate come to head node
341            double angle = 2*Math.PI;
342
343            for (WayInPolygon candidateWay : availableWays) {
344                boolean candidateComingToHead;
345                Node candidatePrevNode;
346
347                if(candidateWay.way.firstNode().equals(headNode)) {
348                    candidateComingToHead = !candidateWay.insideToTheRight;
349                    candidatePrevNode = candidateWay.way.getNode(1);
350                } else if(candidateWay.way.lastNode().equals(headNode)) {
351                     candidateComingToHead = candidateWay.insideToTheRight;
352                     candidatePrevNode = candidateWay.way.getNode(candidateWay.way.getNodesCount() - 2);
353                } else
354                    continue;
355                if(candidateWay.equals(lastWay) && candidateComingToHead)
356                    continue;
357
358                double candidateAngle = getAngle(headNode, candidatePrevNode, prevNode);
359
360                if(mostLeft == null || candidateAngle < angle || (candidateAngle == angle && !candidateComingToHead)) {
361                    // Candidate is most left
362                    mostLeft = candidateWay;
363                    comingToHead = candidateComingToHead;
364                    angle = candidateAngle;
365                }
366            }
367
368            return comingToHead ? mostLeft : null;
369        }
370    }
371
372    /**
373     * Helper storage class for finding findOuterWays
374     * @author viesturs
375     */
376    static class PolygonLevel {
377        public final int level;
378        public final AssembledMultipolygon pol;
379
380        public PolygonLevel(AssembledMultipolygon pol, int level) {
381            this.pol = pol;
382            this.level = level;
383        }
384    }
385
386    /**
387     * Constructs a new {@code JoinAreasAction}.
388     */
389    public JoinAreasAction() {
390        super(tr("Join overlapping Areas"), "joinareas", tr("Joins areas that overlap each other"),
391        Shortcut.registerShortcut("tools:joinareas", tr("Tool: {0}", tr("Join overlapping Areas")),
392            KeyEvent.VK_J, Shortcut.SHIFT), true);
393    }
394
395    /**
396     * Gets called whenever the shortcut is pressed or the menu entry is selected.
397     * Checks whether the selected objects are suitable to join and joins them if so.
398     */
399    @Override
400    public void actionPerformed(ActionEvent e) {
401        join(Main.main.getCurrentDataSet().getSelectedWays());
402    }
403
404    /**
405     * Joins the given ways.
406     * @param ways Ways to join
407     * @since 7534
408     */
409    public void join(Collection<Way> ways) {
410        addedRelations.clear();
411
412        if (ways.isEmpty()) {
413            new Notification(
414                    tr("Please select at least one closed way that should be joined."))
415                    .setIcon(JOptionPane.INFORMATION_MESSAGE)
416                    .show();
417            return;
418        }
419
420        List<Node> allNodes = new ArrayList<>();
421        for (Way way : ways) {
422            if (!way.isClosed()) {
423                new Notification(
424                        tr("One of the selected ways is not closed and therefore cannot be joined."))
425                        .setIcon(JOptionPane.INFORMATION_MESSAGE)
426                        .show();
427                return;
428            }
429
430            allNodes.addAll(way.getNodes());
431        }
432
433        // TODO: Only display this warning when nodes outside dataSourceArea are deleted
434        boolean ok = Command.checkAndConfirmOutlyingOperation("joinarea", tr("Join area confirmation"),
435                trn("The selected way has nodes outside of the downloaded data region.",
436                    "The selected ways have nodes outside of the downloaded data region.",
437                    ways.size()) + "<br/>"
438                    + tr("This can lead to nodes being deleted accidentally.") + "<br/>"
439                    + tr("Are you really sure to continue?")
440                    + tr("Please abort if you are not sure"),
441                tr("The selected area is incomplete. Continue?"),
442                allNodes, null);
443        if(!ok) return;
444
445        //analyze multipolygon relations and collect all areas
446        List<Multipolygon> areas = collectMultipolygons(ways);
447
448        if (areas == null)
449            //too complex multipolygon relations found
450            return;
451
452        if (!testJoin(areas)) {
453            new Notification(
454                    tr("No intersection found. Nothing was changed."))
455                    .setIcon(JOptionPane.INFORMATION_MESSAGE)
456                    .show();
457            return;
458        }
459
460        if (!resolveTagConflicts(areas))
461            return;
462        //user canceled, do nothing.
463
464        try {
465            JoinAreasResult result = joinAreas(areas);
466
467            if (result.hasChanges) {
468                // move tags from ways to newly created relations
469                // TODO: do we need to also move tags for the modified relations?
470                for (Relation r: addedRelations) {
471                    cmds.addAll(CreateMultipolygonAction.removeTagsFromWaysIfNeeded(r));
472                }
473                commitCommands(tr("Move tags from ways to relations"));
474
475                List<Way> allWays = new ArrayList<>();
476                for (Multipolygon pol : result.polygons) {
477                    allWays.add(pol.outerWay);
478                    allWays.addAll(pol.innerWays);
479                }
480                DataSet ds = Main.main.getCurrentDataSet();
481                if (ds != null) {
482                    ds.setSelected(allWays);
483                    Main.map.mapView.repaint();
484                }
485            } else {
486                new Notification(
487                        tr("No intersection found. Nothing was changed."))
488                        .setIcon(JOptionPane.INFORMATION_MESSAGE)
489                        .show();
490            }
491        } catch (UserCancelException exception) {
492            //revert changes
493            //FIXME: this is dirty hack
494            makeCommitsOneAction(tr("Reverting changes"));
495            Main.main.undoRedo.undo();
496            Main.main.undoRedo.redoCommands.clear();
497        }
498    }
499
500    /**
501     * Tests if the areas have some intersections to join.
502     * @param areas Areas to test
503     * @return {@code true} if areas are joinable
504     */
505    private boolean testJoin(List<Multipolygon> areas) {
506        List<Way> allStartingWays = new ArrayList<>();
507
508        for (Multipolygon area : areas) {
509            allStartingWays.add(area.outerWay);
510            allStartingWays.addAll(area.innerWays);
511        }
512
513        //find intersection points
514        Set<Node> nodes = Geometry.addIntersections(allStartingWays, true, cmds);
515        return !nodes.isEmpty();
516    }
517
518    /**
519     * Will join two or more overlapping areas
520     * @param areas list of areas to join
521     * @return new area formed.
522     */
523    private JoinAreasResult joinAreas(List<Multipolygon> areas) throws UserCancelException {
524
525        JoinAreasResult result = new JoinAreasResult();
526        result.hasChanges = false;
527
528        List<Way> allStartingWays = new ArrayList<>();
529        List<Way> innerStartingWays = new ArrayList<>();
530        List<Way> outerStartingWays = new ArrayList<>();
531
532        for (Multipolygon area : areas) {
533            outerStartingWays.add(area.outerWay);
534            innerStartingWays.addAll(area.innerWays);
535        }
536
537        allStartingWays.addAll(innerStartingWays);
538        allStartingWays.addAll(outerStartingWays);
539
540        //first remove nodes in the same coordinate
541        boolean removedDuplicates = false;
542        removedDuplicates |= removeDuplicateNodes(allStartingWays);
543
544        if (removedDuplicates) {
545            result.hasChanges = true;
546            commitCommands(marktr("Removed duplicate nodes"));
547        }
548
549        //find intersection points
550        Set<Node> nodes = Geometry.addIntersections(allStartingWays, false, cmds);
551
552        //no intersections, return.
553        if (nodes.isEmpty())
554            return result;
555        commitCommands(marktr("Added node on all intersections"));
556
557        List<RelationRole> relations = new ArrayList<>();
558
559        // Remove ways from all relations so ways can be combined/split quietly
560        for (Way way : allStartingWays) {
561            relations.addAll(removeFromAllRelations(way));
562        }
563
564        // Don't warn now, because it will really look corrupted
565        boolean warnAboutRelations = !relations.isEmpty() && allStartingWays.size() > 1;
566
567        List<WayInPolygon> preparedWays = new ArrayList<>();
568
569        for (Way way : outerStartingWays) {
570            List<Way> splitWays = splitWayOnNodes(way, nodes);
571            preparedWays.addAll(markWayInsideSide(splitWays, false));
572        }
573
574        for (Way way : innerStartingWays) {
575            List<Way> splitWays = splitWayOnNodes(way, nodes);
576            preparedWays.addAll(markWayInsideSide(splitWays, true));
577        }
578
579        // Find boundary ways
580        List<Way> discardedWays = new ArrayList<>();
581        List<AssembledPolygon> bounadries = findBoundaryPolygons(preparedWays, discardedWays);
582
583        //find polygons
584        List<AssembledMultipolygon> preparedPolygons = findPolygons(bounadries);
585
586
587        //assemble final polygons
588        List<Multipolygon> polygons = new ArrayList<>();
589        Set<Relation> relationsToDelete = new LinkedHashSet<>();
590
591        for (AssembledMultipolygon pol : preparedPolygons) {
592
593            //create the new ways
594            Multipolygon resultPol = joinPolygon(pol);
595
596            //create multipolygon relation, if necessary.
597            RelationRole ownMultipolygonRelation = addOwnMultigonRelation(resultPol.innerWays, resultPol.outerWay);
598
599            //add back the original relations, merged with our new multipolygon relation
600            fixRelations(relations, resultPol.outerWay, ownMultipolygonRelation, relationsToDelete);
601
602            //strip tags from inner ways
603            //TODO: preserve tags on existing inner ways
604            stripTags(resultPol.innerWays);
605
606            polygons.add(resultPol);
607        }
608
609        commitCommands(marktr("Assemble new polygons"));
610
611        for(Relation rel: relationsToDelete) {
612            cmds.add(new DeleteCommand(rel));
613        }
614
615        commitCommands(marktr("Delete relations"));
616
617        // Delete the discarded inner ways
618        if (!discardedWays.isEmpty()) {
619            Command deleteCmd = DeleteCommand.delete(Main.main.getEditLayer(), discardedWays, true);
620            if (deleteCmd != null) {
621                cmds.add(deleteCmd);
622                commitCommands(marktr("Delete Ways that are not part of an inner multipolygon"));
623            }
624        }
625
626        makeCommitsOneAction(marktr("Joined overlapping areas"));
627
628        if (warnAboutRelations) {
629            new Notification(
630                    tr("Some of the ways were part of relations that have been modified.<br>Please verify no errors have been introduced."))
631                    .setIcon(JOptionPane.INFORMATION_MESSAGE)
632                    .setDuration(Notification.TIME_LONG)
633                    .show();
634        }
635
636        result.hasChanges = true;
637        result.polygons = polygons;
638        return result;
639    }
640
641    /**
642     * Checks if tags of two given ways differ, and presents the user a dialog to solve conflicts
643     * @param polygons ways to check
644     * @return {@code true} if all conflicts are resolved, {@code false} if conflicts remain.
645     */
646    private boolean resolveTagConflicts(List<Multipolygon> polygons) {
647
648        List<Way> ways = new ArrayList<>();
649
650        for (Multipolygon pol : polygons) {
651            ways.add(pol.outerWay);
652            ways.addAll(pol.innerWays);
653        }
654
655        if (ways.size() < 2) {
656            return true;
657        }
658
659        TagCollection wayTags = TagCollection.unionOfAllPrimitives(ways);
660        try {
661            cmds.addAll(CombinePrimitiveResolverDialog.launchIfNecessary(wayTags, ways, ways));
662            commitCommands(marktr("Fix tag conflicts"));
663            return true;
664        } catch (UserCancelException ex) {
665            return false;
666        }
667    }
668
669    /**
670     * This method removes duplicate points (if any) from the input way.
671     * @param ways the ways to process
672     * @return {@code true} if any changes where made
673     */
674    private boolean removeDuplicateNodes(List<Way> ways) {
675        //TODO: maybe join nodes with JoinNodesAction, rather than reconnect the ways.
676
677        Map<Node, Node> nodeMap = new TreeMap<>(new NodePositionComparator());
678        int totalNodesRemoved = 0;
679
680        for (Way way : ways) {
681            if (way.getNodes().size() < 2) {
682                continue;
683            }
684
685            int nodesRemoved = 0;
686            List<Node> newNodes = new ArrayList<>();
687            Node prevNode = null;
688
689            for (Node node : way.getNodes()) {
690                if (!nodeMap.containsKey(node)) {
691                    //new node
692                    nodeMap.put(node, node);
693
694                    //avoid duplicate nodes
695                    if (prevNode != node) {
696                        newNodes.add(node);
697                    } else {
698                        nodesRemoved ++;
699                    }
700                } else {
701                    //node with same coordinates already exists, substitute with existing node
702                    Node representator = nodeMap.get(node);
703
704                    if (representator != node) {
705                        nodesRemoved ++;
706                    }
707
708                    //avoid duplicate node
709                    if (prevNode != representator) {
710                        newNodes.add(representator);
711                    }
712                }
713                prevNode = node;
714            }
715
716            if (nodesRemoved > 0) {
717
718                if (newNodes.size() == 1) { //all nodes in the same coordinate - add one more node, to have closed way.
719                    newNodes.add(newNodes.get(0));
720                }
721
722                Way newWay=new Way(way);
723                newWay.setNodes(newNodes);
724                cmds.add(new ChangeCommand(way, newWay));
725                totalNodesRemoved += nodesRemoved;
726            }
727        }
728
729        return totalNodesRemoved > 0;
730    }
731
732    /**
733     * Commits the command list with a description
734     * @param description The description of what the commands do
735     */
736    private void commitCommands(String description) {
737        switch(cmds.size()) {
738        case 0:
739            return;
740        case 1:
741            Main.main.undoRedo.add(cmds.getFirst());
742            break;
743        default:
744            Command c = new SequenceCommand(tr(description), cmds);
745            Main.main.undoRedo.add(c);
746            break;
747        }
748
749        cmds.clear();
750        cmdsCount++;
751    }
752
753    /**
754     * This method analyzes the way and assigns each part what direction polygon "inside" is.
755     * @param parts the split parts of the way
756     * @param isInner - if true, reverts the direction (for multipolygon islands)
757     * @return list of parts, marked with the inside orientation.
758     */
759    private List<WayInPolygon> markWayInsideSide(List<Way> parts, boolean isInner) {
760
761        List<WayInPolygon> result = new ArrayList<>();
762
763        //prepare prev and next maps
764        Map<Way, Way> nextWayMap = new HashMap<>();
765        Map<Way, Way> prevWayMap = new HashMap<>();
766
767        for (int pos = 0; pos < parts.size(); pos ++) {
768
769            if (!parts.get(pos).lastNode().equals(parts.get((pos + 1) % parts.size()).firstNode()))
770                throw new RuntimeException("Way not circular");
771
772            nextWayMap.put(parts.get(pos), parts.get((pos + 1) % parts.size()));
773            prevWayMap.put(parts.get(pos), parts.get((pos + parts.size() - 1) % parts.size()));
774        }
775
776        //find the node with minimum y - it's guaranteed to be outer. (What about the south pole?)
777        Way topWay = null;
778        Node topNode = null;
779        int topIndex = 0;
780        double minY = Double.POSITIVE_INFINITY;
781
782        for (Way way : parts) {
783            for (int pos = 0; pos < way.getNodesCount(); pos ++) {
784                Node node = way.getNode(pos);
785
786                if (node.getEastNorth().getY() < minY) {
787                    minY = node.getEastNorth().getY();
788                    topWay = way;
789                    topNode = node;
790                    topIndex = pos;
791                }
792            }
793        }
794
795        //get the upper way and it's orientation.
796
797        boolean wayClockwise; // orientation of the top way.
798
799        if (topNode.equals(topWay.firstNode()) || topNode.equals(topWay.lastNode())) {
800            Node headNode = null; // the node at junction
801            Node prevNode = null; // last node from previous path
802            wayClockwise = false;
803
804            //node is in split point - find the outermost way from this point
805
806            headNode = topNode;
807            //make a fake node that is downwards from head node (smaller Y). It will be a division point between paths.
808            prevNode = new Node(new EastNorth(headNode.getEastNorth().getX(), headNode.getEastNorth().getY() - 1e5));
809
810            topWay = null;
811            wayClockwise = false;
812            Node bestWayNextNode = null;
813
814            for (Way way : parts) {
815                if (way.firstNode().equals(headNode)) {
816                    Node nextNode = way.getNode(1);
817
818                    if (topWay == null || !Geometry.isToTheRightSideOfLine(prevNode, headNode, bestWayNextNode, nextNode)) {
819                        //the new way is better
820                        topWay = way;
821                        wayClockwise = true;
822                        bestWayNextNode = nextNode;
823                    }
824                }
825
826                if (way.lastNode().equals(headNode)) {
827                    //end adjacent to headNode
828                    Node nextNode = way.getNode(way.getNodesCount() - 2);
829
830                    if (topWay == null || !Geometry.isToTheRightSideOfLine(prevNode, headNode, bestWayNextNode, nextNode)) {
831                        //the new way is better
832                        topWay = way;
833                        wayClockwise = false;
834                        bestWayNextNode = nextNode;
835                    }
836                }
837            }
838        } else {
839            //node is inside way - pick the clockwise going end.
840            Node prev = topWay.getNode(topIndex - 1);
841            Node next = topWay.getNode(topIndex + 1);
842
843            //there will be no parallel segments in the middle of way, so all fine.
844            wayClockwise = Geometry.angleIsClockwise(prev, topNode, next);
845        }
846
847        Way curWay = topWay;
848        boolean curWayInsideToTheRight = wayClockwise ^ isInner;
849
850        //iterate till full circle is reached
851        while (true) {
852
853            //add cur way
854            WayInPolygon resultWay = new WayInPolygon(curWay, curWayInsideToTheRight);
855            result.add(resultWay);
856
857            //process next way
858            Way nextWay = nextWayMap.get(curWay);
859            Node prevNode = curWay.getNode(curWay.getNodesCount() - 2);
860            Node headNode = curWay.lastNode();
861            Node nextNode = nextWay.getNode(1);
862
863            if (nextWay == topWay) {
864                //full loop traversed - all done.
865                break;
866            }
867
868            //find intersecting segments
869            // the intersections will look like this:
870            //
871            //                       ^
872            //                       |
873            //                       X wayBNode
874            //                       |
875            //                  wayB |
876            //                       |
877            //             curWay    |       nextWay
878            //----X----------------->X----------------------X---->
879            //    prevNode           ^headNode              nextNode
880            //                       |
881            //                       |
882            //                  wayA |
883            //                       |
884            //                       X wayANode
885            //                       |
886
887            int intersectionCount = 0;
888
889            for (Way wayA : parts) {
890
891                if (wayA == curWay) {
892                    continue;
893                }
894
895                if (wayA.lastNode().equals(headNode)) {
896
897                    Way wayB = nextWayMap.get(wayA);
898
899                    //test if wayA is opposite wayB relative to curWay and nextWay
900
901                    Node wayANode = wayA.getNode(wayA.getNodesCount() - 2);
902                    Node wayBNode = wayB.getNode(1);
903
904                    boolean wayAToTheRight = Geometry.isToTheRightSideOfLine(prevNode, headNode, nextNode, wayANode);
905                    boolean wayBToTheRight = Geometry.isToTheRightSideOfLine(prevNode, headNode, nextNode, wayBNode);
906
907                    if (wayAToTheRight != wayBToTheRight) {
908                        intersectionCount ++;
909                    }
910                }
911            }
912
913            //if odd number of crossings, invert orientation
914            if (intersectionCount % 2 != 0) {
915                curWayInsideToTheRight = !curWayInsideToTheRight;
916            }
917
918            curWay = nextWay;
919        }
920
921        return result;
922    }
923
924    /**
925     * This is a method splits way into smaller parts, using the prepared nodes list as split points.
926     * Uses {@link SplitWayAction#splitWay} for the heavy lifting.
927     * @return list of split ways (or original ways if no splitting is done).
928     */
929    private List<Way> splitWayOnNodes(Way way, Set<Node> nodes) {
930
931        List<Way> result = new ArrayList<>();
932        List<List<Node>> chunks = buildNodeChunks(way, nodes);
933
934        if (chunks.size() > 1) {
935            SplitWayResult split = SplitWayAction.splitWay(getEditLayer(), way, chunks, Collections.<OsmPrimitive>emptyList());
936
937            //execute the command, we need the results
938            cmds.add(split.getCommand());
939            commitCommands(marktr("Split ways into fragments"));
940
941            result.add(split.getOriginalWay());
942            result.addAll(split.getNewWays());
943        } else {
944            //nothing to split
945            result.add(way);
946        }
947
948        return result;
949    }
950
951    /**
952     * Simple chunking version. Does not care about circular ways and result being
953     * proper, we will glue it all back together later on.
954     * @param way the way to chunk
955     * @param splitNodes the places where to cut.
956     * @return list of node paths to produce.
957     */
958    private List<List<Node>> buildNodeChunks(Way way, Collection<Node> splitNodes) {
959        List<List<Node>> result = new ArrayList<>();
960        List<Node> curList = new ArrayList<>();
961
962        for (Node node : way.getNodes()) {
963            curList.add(node);
964            if (curList.size() > 1 && splitNodes.contains(node)) {
965                result.add(curList);
966                curList = new ArrayList<>();
967                curList.add(node);
968            }
969        }
970
971        if (curList.size() > 1) {
972            result.add(curList);
973        }
974
975        return result;
976    }
977
978    /**
979     * This method finds which ways are outer and which are inner.
980     * @param boundaries list of joined boundaries to search in
981     * @return outer ways
982     */
983    private List<AssembledMultipolygon> findPolygons(Collection<AssembledPolygon> boundaries) {
984
985        List<PolygonLevel> list = findOuterWaysImpl(0, boundaries);
986        List<AssembledMultipolygon> result = new ArrayList<>();
987
988        //take every other level
989        for (PolygonLevel pol : list) {
990            if (pol.level % 2 == 0) {
991                result.add(pol.pol);
992            }
993        }
994
995        return result;
996    }
997
998    /**
999     * Collects outer way and corresponding inner ways from all boundaries.
1000     * @param level depth level
1001     * @param boundaryWays
1002     * @return the outermostWay.
1003     */
1004    private List<PolygonLevel> findOuterWaysImpl(int level, Collection<AssembledPolygon> boundaryWays) {
1005
1006        //TODO: bad performance for deep nestings...
1007        List<PolygonLevel> result = new ArrayList<>();
1008
1009        for (AssembledPolygon outerWay : boundaryWays) {
1010
1011            boolean outerGood = true;
1012            List<AssembledPolygon> innerCandidates = new ArrayList<>();
1013
1014            for (AssembledPolygon innerWay : boundaryWays) {
1015                if (innerWay == outerWay) {
1016                    continue;
1017                }
1018
1019                if (wayInsideWay(outerWay, innerWay)) {
1020                    outerGood = false;
1021                    break;
1022                } else if (wayInsideWay(innerWay, outerWay)) {
1023                    innerCandidates.add(innerWay);
1024                }
1025            }
1026
1027            if (!outerGood) {
1028                continue;
1029            }
1030
1031            //add new outer polygon
1032            AssembledMultipolygon pol = new AssembledMultipolygon(outerWay);
1033            PolygonLevel polLev = new PolygonLevel(pol, level);
1034
1035            //process inner ways
1036            if (!innerCandidates.isEmpty()) {
1037                List<PolygonLevel> innerList = findOuterWaysImpl(level + 1, innerCandidates);
1038                result.addAll(innerList);
1039
1040                for (PolygonLevel pl : innerList) {
1041                    if (pl.level == level + 1) {
1042                        pol.innerWays.add(pl.pol.outerWay);
1043                    }
1044                }
1045            }
1046
1047            result.add(polLev);
1048        }
1049
1050        return result;
1051    }
1052
1053    /**
1054     * Finds all ways that form inner or outer boundaries.
1055     * @param multigonWays A list of (splitted) ways that form a multigon and share common end nodes on intersections.
1056     * @param discardedResult this list is filled with ways that are to be discarded
1057     * @return A list of ways that form the outer and inner boundaries of the multigon.
1058     */
1059    public static List<AssembledPolygon> findBoundaryPolygons(Collection<WayInPolygon> multigonWays,
1060            List<Way> discardedResult) {
1061        //first find all discardable ways, by getting outer shells.
1062        //this will produce incorrect boundaries in some cases, but second pass will fix it.
1063        List<WayInPolygon> discardedWays = new ArrayList<>();
1064
1065        // In multigonWays collection, some way are just a point (i.e. way like nodeA-nodeA)
1066        // This seems to appear when is apply over invalid way like #9911 test-case
1067        // Remove all of these way to make the next work.
1068        ArrayList<WayInPolygon> cleanMultigonWays = new ArrayList<>();
1069        for(WayInPolygon way: multigonWays)
1070            if(way.way.getNodesCount() == 2 && way.way.firstNode() == way.way.lastNode())
1071                discardedWays.add(way);
1072            else
1073                cleanMultigonWays.add(way);
1074
1075        WayTraverser traverser = new WayTraverser(cleanMultigonWays);
1076        List<AssembledPolygon> result = new ArrayList<>();
1077
1078        WayInPolygon startWay;
1079        while((startWay = traverser.startNewWay()) != null) {
1080            ArrayList<WayInPolygon> path = new ArrayList<>();
1081            List<WayInPolygon> startWays = new ArrayList<>();
1082            path.add(startWay);
1083            while(true) {
1084                WayInPolygon leftComing;
1085                while((leftComing = traverser.leftComingWay()) != null) {
1086                    if(startWays.contains(leftComing))
1087                        break;
1088                    // Need restart traverser walk
1089                    path.clear();
1090                    path.add(leftComing);
1091                    traverser.setStartWay(leftComing);
1092                    startWays.add(leftComing);
1093                    break;
1094                }
1095                WayInPolygon nextWay = traverser.walk();
1096                if(nextWay == null)
1097                    throw new RuntimeException("Join areas internal error.");
1098                if(path.get(0) == nextWay) {
1099                    // path is closed -> stop here
1100                    AssembledPolygon ring = new AssembledPolygon(path);
1101                    if(ring.getNodes().size() <= 2) {
1102                        // Invalid ring (2 nodes) -> remove
1103                        traverser.removeWays(path);
1104                        for(WayInPolygon way: path)
1105                            discardedResult.add(way.way);
1106                    } else {
1107                        // Close ring -> add
1108                        result.add(ring);
1109                        traverser.removeWays(path);
1110                    }
1111                    break;
1112                }
1113                if(path.contains(nextWay)) {
1114                    // Inner loop -> remove
1115                    int index = path.indexOf(nextWay);
1116                    while(path.size() > index) {
1117                        WayInPolygon currentWay = path.get(index);
1118                        discardedResult.add(currentWay.way);
1119                        traverser.removeWay(currentWay);
1120                        path.remove(index);
1121                    }
1122                    traverser.setStartWay(path.get(index-1));
1123                } else {
1124                    path.add(nextWay);
1125                }
1126            }
1127        }
1128
1129        return fixTouchingPolygons(result);
1130    }
1131
1132    /**
1133     * This method checks if polygons have several touching parts and splits them in several polygons.
1134     * @param polygons the polygons to process.
1135     */
1136    public static List<AssembledPolygon> fixTouchingPolygons(List<AssembledPolygon> polygons) {
1137        List<AssembledPolygon> newPolygons = new ArrayList<>();
1138
1139        for (AssembledPolygon ring : polygons) {
1140            ring.reverse();
1141            WayTraverser traverser = new WayTraverser(ring.ways);
1142            WayInPolygon startWay;
1143
1144            while((startWay = traverser.startNewWay()) != null) {
1145                List<WayInPolygon> simpleRingWays = new ArrayList<>();
1146                simpleRingWays.add(startWay);
1147                WayInPolygon nextWay;
1148                while((nextWay = traverser.walk()) != startWay) {
1149                    if(nextWay == null)
1150                        throw new RuntimeException("Join areas internal error.");
1151                    simpleRingWays.add(nextWay);
1152                }
1153                traverser.removeWays(simpleRingWays);
1154                AssembledPolygon simpleRing = new AssembledPolygon(simpleRingWays);
1155                simpleRing.reverse();
1156                newPolygons.add(simpleRing);
1157            }
1158        }
1159
1160        return newPolygons;
1161    }
1162
1163    /**
1164     * Tests if way is inside other way
1165     * @param outside outer polygon description
1166     * @param inside inner polygon description
1167     * @return {@code true} if inner is inside outer
1168     */
1169    public static boolean wayInsideWay(AssembledPolygon inside, AssembledPolygon outside) {
1170        Set<Node> outsideNodes = new HashSet<>(outside.getNodes());
1171        List<Node> insideNodes = inside.getNodes();
1172
1173        for (Node insideNode : insideNodes) {
1174
1175            if (!outsideNodes.contains(insideNode))
1176                //simply test the one node
1177                return Geometry.nodeInsidePolygon(insideNode, outside.getNodes());
1178        }
1179
1180        //all nodes shared.
1181        return false;
1182    }
1183
1184    /**
1185     * Joins the lists of ways.
1186     * @param polygon The list of outer ways that belong to that multigon.
1187     * @return The newly created outer way
1188     */
1189    private Multipolygon  joinPolygon(AssembledMultipolygon polygon) throws UserCancelException {
1190        Multipolygon result = new Multipolygon(joinWays(polygon.outerWay.ways));
1191
1192        for (AssembledPolygon pol : polygon.innerWays) {
1193            result.innerWays.add(joinWays(pol.ways));
1194        }
1195
1196        return result;
1197    }
1198
1199    /**
1200     * Joins the outer ways and deletes all short ways that can't be part of a multipolygon anyway.
1201     * @param ways The list of outer ways that belong to that multigon.
1202     * @return The newly created outer way
1203     */
1204    private Way joinWays(List<WayInPolygon> ways) throws UserCancelException {
1205
1206        //leave original orientation, if all paths are reverse.
1207        boolean allReverse = true;
1208        for (WayInPolygon way : ways) {
1209            allReverse &= !way.insideToTheRight;
1210        }
1211
1212        if (allReverse) {
1213            for (WayInPolygon way : ways) {
1214                way.insideToTheRight = !way.insideToTheRight;
1215            }
1216        }
1217
1218        Way joinedWay = joinOrientedWays(ways);
1219
1220        //should not happen
1221        if (joinedWay == null || !joinedWay.isClosed())
1222            throw new RuntimeException("Join areas internal error.");
1223
1224        return joinedWay;
1225    }
1226
1227    /**
1228     * Joins a list of ways (using CombineWayAction and ReverseWayAction as specified in WayInPath)
1229     * @param ways The list of ways to join and reverse
1230     * @return The newly created way
1231     */
1232    private Way joinOrientedWays(List<WayInPolygon> ways) throws UserCancelException{
1233        if (ways.size() < 2)
1234            return ways.get(0).way;
1235
1236        // This will turn ways so all of them point in the same direction and CombineAction won't bug
1237        // the user about this.
1238
1239        //TODO: ReverseWay and Combine way are really slow and we use them a lot here. This slows down large joins.
1240        List<Way> actionWays = new ArrayList<>(ways.size());
1241
1242        for (WayInPolygon way : ways) {
1243            actionWays.add(way.way);
1244
1245            if (!way.insideToTheRight) {
1246                ReverseWayResult res = ReverseWayAction.reverseWay(way.way);
1247                Main.main.undoRedo.add(res.getReverseCommand());
1248                cmdsCount++;
1249            }
1250        }
1251
1252        Pair<Way, Command> result = CombineWayAction.combineWaysWorker(actionWays);
1253
1254        Main.main.undoRedo.add(result.b);
1255        cmdsCount ++;
1256
1257        return result.a;
1258    }
1259
1260    /**
1261     * This method analyzes multipolygon relationships of given ways and collects addition inner ways to consider.
1262     * @param selectedWays the selected ways
1263     * @return list of polygons, or null if too complex relation encountered.
1264     */
1265    private List<Multipolygon> collectMultipolygons(Collection<Way> selectedWays) {
1266
1267        List<Multipolygon> result = new ArrayList<>();
1268
1269        //prepare the lists, to minimize memory allocation.
1270        List<Way> outerWays = new ArrayList<>();
1271        List<Way> innerWays = new ArrayList<>();
1272
1273        Set<Way> processedOuterWays = new LinkedHashSet<>();
1274        Set<Way> processedInnerWays = new LinkedHashSet<>();
1275
1276        for (Relation r : OsmPrimitive.getParentRelations(selectedWays)) {
1277            if (r.isDeleted() || !r.isMultipolygon()) {
1278                continue;
1279            }
1280
1281            boolean hasKnownOuter = false;
1282            outerWays.clear();
1283            innerWays.clear();
1284
1285            for (RelationMember rm : r.getMembers()) {
1286                if ("outer".equalsIgnoreCase(rm.getRole())) {
1287                    outerWays.add(rm.getWay());
1288                    hasKnownOuter |= selectedWays.contains(rm.getWay());
1289                }
1290                else if ("inner".equalsIgnoreCase(rm.getRole())) {
1291                    innerWays.add(rm.getWay());
1292                }
1293            }
1294
1295            if (!hasKnownOuter) {
1296                continue;
1297            }
1298
1299            if (outerWays.size() > 1) {
1300                new Notification(
1301                        tr("Sorry. Cannot handle multipolygon relations with multiple outer ways."))
1302                        .setIcon(JOptionPane.INFORMATION_MESSAGE)
1303                        .show();
1304                return null;
1305            }
1306
1307            Way outerWay = outerWays.get(0);
1308
1309            //retain only selected inner ways
1310            innerWays.retainAll(selectedWays);
1311
1312            if (processedOuterWays.contains(outerWay)) {
1313                new Notification(
1314                        tr("Sorry. Cannot handle way that is outer in multiple multipolygon relations."))
1315                        .setIcon(JOptionPane.INFORMATION_MESSAGE)
1316                        .show();
1317                return null;
1318            }
1319
1320            if (processedInnerWays.contains(outerWay)) {
1321                new Notification(
1322                        tr("Sorry. Cannot handle way that is both inner and outer in multipolygon relations."))
1323                        .setIcon(JOptionPane.INFORMATION_MESSAGE)
1324                        .show();
1325                return null;
1326            }
1327
1328            for (Way way :innerWays)
1329            {
1330                if (processedOuterWays.contains(way)) {
1331                    new Notification(
1332                            tr("Sorry. Cannot handle way that is both inner and outer in multipolygon relations."))
1333                            .setIcon(JOptionPane.INFORMATION_MESSAGE)
1334                            .show();
1335                    return null;
1336                }
1337
1338                if (processedInnerWays.contains(way)) {
1339                    new Notification(
1340                            tr("Sorry. Cannot handle way that is inner in multiple multipolygon relations."))
1341                            .setIcon(JOptionPane.INFORMATION_MESSAGE)
1342                            .show();
1343                    return null;
1344                }
1345            }
1346
1347            processedOuterWays.add(outerWay);
1348            processedInnerWays.addAll(innerWays);
1349
1350            Multipolygon pol = new Multipolygon(outerWay);
1351            pol.innerWays.addAll(innerWays);
1352
1353            result.add(pol);
1354        }
1355
1356        //add remaining ways, not in relations
1357        for (Way way : selectedWays) {
1358            if (processedOuterWays.contains(way) || processedInnerWays.contains(way)) {
1359                continue;
1360            }
1361
1362            result.add(new Multipolygon(way));
1363        }
1364
1365        return result;
1366    }
1367
1368    /**
1369     * Will add own multipolygon relation to the "previously existing" relations. Fixup is done by fixRelations
1370     * @param inner List of already closed inner ways
1371     * @param outer The outer way
1372     * @return The list of relation with roles to add own relation to
1373     */
1374    private RelationRole addOwnMultigonRelation(Collection<Way> inner, Way outer) {
1375        if (inner.isEmpty()) return null;
1376        // Create new multipolygon relation and add all inner ways to it
1377        Relation newRel = new Relation();
1378        newRel.put("type", "multipolygon");
1379        for (Way w : inner) {
1380            newRel.addMember(new RelationMember("inner", w));
1381        }
1382        cmds.add(new AddCommand(newRel));
1383        addedRelations.add(newRel);
1384
1385        // We don't add outer to the relation because it will be handed to fixRelations()
1386        // which will then do the remaining work.
1387        return new RelationRole(newRel, "outer");
1388    }
1389
1390    /**
1391     * Removes a given OsmPrimitive from all relations.
1392     * @param osm Element to remove from all relations
1393     * @return List of relations with roles the primitives was part of
1394     */
1395    private List<RelationRole> removeFromAllRelations(OsmPrimitive osm) {
1396        List<RelationRole> result = new ArrayList<>();
1397
1398        for (Relation r : Main.main.getCurrentDataSet().getRelations()) {
1399            if (r.isDeleted()) {
1400                continue;
1401            }
1402            for (RelationMember rm : r.getMembers()) {
1403                if (rm.getMember() != osm) {
1404                    continue;
1405                }
1406
1407                Relation newRel = new Relation(r);
1408                List<RelationMember> members = newRel.getMembers();
1409                members.remove(rm);
1410                newRel.setMembers(members);
1411
1412                cmds.add(new ChangeCommand(r, newRel));
1413                RelationRole saverel =  new RelationRole(r, rm.getRole());
1414                if (!result.contains(saverel)) {
1415                    result.add(saverel);
1416                }
1417                break;
1418            }
1419        }
1420
1421        commitCommands(marktr("Removed Element from Relations"));
1422        return result;
1423    }
1424
1425    /**
1426     * Adds the previously removed relations again to the outer way. If there are multiple multipolygon
1427     * relations where the joined areas were in "outer" role a new relation is created instead with all
1428     * members of both. This function depends on multigon relations to be valid already, it won't fix them.
1429     * @param rels List of relations with roles the (original) ways were part of
1430     * @param outer The newly created outer area/way
1431     * @param ownMultipol elements to directly add as outer
1432     * @param relationsToDelete set of relations to delete.
1433     */
1434    private void fixRelations(List<RelationRole> rels, Way outer, RelationRole ownMultipol, Set<Relation> relationsToDelete) {
1435        List<RelationRole> multiouters = new ArrayList<>();
1436
1437        if (ownMultipol != null) {
1438            multiouters.add(ownMultipol);
1439        }
1440
1441        for (RelationRole r : rels) {
1442            if (r.rel.isMultipolygon() && "outer".equalsIgnoreCase(r.role)) {
1443                multiouters.add(r);
1444                continue;
1445            }
1446            // Add it back!
1447            Relation newRel = new Relation(r.rel);
1448            newRel.addMember(new RelationMember(r.role, outer));
1449            cmds.add(new ChangeCommand(r.rel, newRel));
1450        }
1451
1452        Relation newRel;
1453        switch (multiouters.size()) {
1454        case 0:
1455            return;
1456        case 1:
1457            // Found only one to be part of a multipolygon relation, so just add it back as well
1458            newRel = new Relation(multiouters.get(0).rel);
1459            newRel.addMember(new RelationMember(multiouters.get(0).role, outer));
1460            cmds.add(new ChangeCommand(multiouters.get(0).rel, newRel));
1461            return;
1462        default:
1463            // Create a new relation with all previous members and (Way)outer as outer.
1464            newRel = new Relation();
1465            for (RelationRole r : multiouters) {
1466                // Add members
1467                for (RelationMember rm : r.rel.getMembers())
1468                    if (!newRel.getMembers().contains(rm)) {
1469                        newRel.addMember(rm);
1470                    }
1471                // Add tags
1472                for (String key : r.rel.keySet()) {
1473                    newRel.put(key, r.rel.get(key));
1474                }
1475                // Delete old relation
1476                relationsToDelete.add(r.rel);
1477            }
1478            newRel.addMember(new RelationMember("outer", outer));
1479            cmds.add(new AddCommand(newRel));
1480        }
1481    }
1482
1483    /**
1484     * Remove all tags from the all the way
1485     * @param ways The List of Ways to remove all tags from
1486     */
1487    private void stripTags(Collection<Way> ways) {
1488        for (Way w : ways) {
1489            stripTags(w);
1490        }
1491        /* I18N: current action printed in status display */
1492        commitCommands(marktr("Remove tags from inner ways"));
1493    }
1494
1495    /**
1496     * Remove all tags from the way
1497     * @param x The Way to remove all tags from
1498     */
1499    private void stripTags(Way x) {
1500        Way y = new Way(x);
1501        for (String key : x.keySet()) {
1502            y.remove(key);
1503        }
1504        cmds.add(new ChangeCommand(x, y));
1505    }
1506
1507    /**
1508     * Takes the last cmdsCount actions back and combines them into a single action
1509     * (for when the user wants to undo the join action)
1510     * @param message The commit message to display
1511     */
1512    private void makeCommitsOneAction(String message) {
1513        UndoRedoHandler ur = Main.main.undoRedo;
1514        cmds.clear();
1515        int i = Math.max(ur.commands.size() - cmdsCount, 0);
1516        for (; i < ur.commands.size(); i++) {
1517            cmds.add(ur.commands.get(i));
1518        }
1519
1520        for (i = 0; i < cmds.size(); i++) {
1521            ur.undo();
1522        }
1523
1524        commitCommands(message == null ? marktr("Join Areas Function") : message);
1525        cmdsCount = 0;
1526    }
1527
1528    @Override
1529    protected void updateEnabledState() {
1530        if (getCurrentDataSet() == null) {
1531            setEnabled(false);
1532        } else {
1533            updateEnabledState(getCurrentDataSet().getSelected());
1534        }
1535    }
1536
1537    @Override
1538    protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) {
1539        setEnabled(selection != null && !selection.isEmpty());
1540    }
1541}