001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.command;
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.GridBagLayout;
009import java.util.ArrayList;
010import java.util.Arrays;
011import java.util.Collection;
012import java.util.Collections;
013import java.util.EnumSet;
014import java.util.HashMap;
015import java.util.HashSet;
016import java.util.LinkedList;
017import java.util.List;
018import java.util.Map;
019import java.util.Map.Entry;
020import java.util.Objects;
021import java.util.Set;
022
023import javax.swing.Icon;
024import javax.swing.JOptionPane;
025import javax.swing.JPanel;
026
027import org.openstreetmap.josm.Main;
028import org.openstreetmap.josm.actions.SplitWayAction;
029import org.openstreetmap.josm.actions.SplitWayAction.SplitWayResult;
030import org.openstreetmap.josm.data.osm.DataSet;
031import org.openstreetmap.josm.data.osm.Node;
032import org.openstreetmap.josm.data.osm.OsmPrimitive;
033import org.openstreetmap.josm.data.osm.OsmPrimitiveType;
034import org.openstreetmap.josm.data.osm.PrimitiveData;
035import org.openstreetmap.josm.data.osm.Relation;
036import org.openstreetmap.josm.data.osm.RelationToChildReference;
037import org.openstreetmap.josm.data.osm.Way;
038import org.openstreetmap.josm.data.osm.WaySegment;
039import org.openstreetmap.josm.gui.ConditionalOptionPaneUtil;
040import org.openstreetmap.josm.gui.DefaultNameFormatter;
041import org.openstreetmap.josm.gui.dialogs.DeleteFromRelationConfirmationDialog;
042import org.openstreetmap.josm.gui.layer.OsmDataLayer;
043import org.openstreetmap.josm.gui.widgets.JMultilineLabel;
044import org.openstreetmap.josm.tools.CheckParameterUtil;
045import org.openstreetmap.josm.tools.ImageProvider;
046import org.openstreetmap.josm.tools.Utils;
047
048/**
049 * A command to delete a number of primitives from the dataset.
050 * @since 23
051 */
052public class DeleteCommand extends Command {
053    private static final class DeleteChildCommand implements PseudoCommand {
054        private final OsmPrimitive osm;
055
056        private DeleteChildCommand(OsmPrimitive osm) {
057            this.osm = osm;
058        }
059
060        @Override
061        public String getDescriptionText() {
062            return tr("Deleted ''{0}''", osm.getDisplayName(DefaultNameFormatter.getInstance()));
063        }
064
065        @Override
066        public Icon getDescriptionIcon() {
067            return ImageProvider.get(osm.getDisplayType());
068        }
069
070        @Override
071        public Collection<? extends OsmPrimitive> getParticipatingPrimitives() {
072            return Collections.singleton(osm);
073        }
074
075        @Override
076        public String toString() {
077            return "DeleteChildCommand [osm=" + osm + "]";
078        }
079    }
080
081    /**
082     * The primitives that get deleted.
083     */
084    private final Collection<? extends OsmPrimitive> toDelete;
085    private final Map<OsmPrimitive, PrimitiveData> clonedPrimitives = new HashMap<>();
086
087    /**
088     * Constructor. Deletes a collection of primitives in the current edit layer.
089     *
090     * @param data the primitives to delete. Must neither be null nor empty.
091     * @throws IllegalArgumentException if data is null or empty
092     */
093    public DeleteCommand(Collection<? extends OsmPrimitive> data) {
094        CheckParameterUtil.ensureParameterNotNull(data, "data");
095        this.toDelete = data;
096        checkConsistency();
097    }
098
099    /**
100     * Constructor. Deletes a single primitive in the current edit layer.
101     *
102     * @param data  the primitive to delete. Must not be null.
103     * @throws IllegalArgumentException if data is null
104     */
105    public DeleteCommand(OsmPrimitive data) {
106        this(Collections.singleton(data));
107    }
108
109    /**
110     * Constructor for a single data item. Use the collection constructor to delete multiple
111     * objects.
112     *
113     * @param layer the layer context for deleting this primitive. Must not be null.
114     * @param data the primitive to delete. Must not be null.
115     * @throws IllegalArgumentException if data is null
116     * @throws IllegalArgumentException if layer is null
117     */
118    public DeleteCommand(OsmDataLayer layer, OsmPrimitive data) {
119        this(layer, Collections.singleton(data));
120    }
121
122    /**
123     * Constructor for a collection of data to be deleted in the context of
124     * a specific layer
125     *
126     * @param layer the layer context for deleting these primitives. Must not be null.
127     * @param data the primitives to delete. Must neither be null nor empty.
128     * @throws IllegalArgumentException if layer is null
129     * @throws IllegalArgumentException if data is null or empty
130     */
131    public DeleteCommand(OsmDataLayer layer, Collection<? extends OsmPrimitive> data) {
132        super(layer);
133        CheckParameterUtil.ensureParameterNotNull(data, "data");
134        this.toDelete = data;
135        checkConsistency();
136    }
137
138    /**
139     * Constructor for a collection of data to be deleted in the context of
140     * a specific data set
141     *
142     * @param dataset the dataset context for deleting these primitives. Must not be null.
143     * @param data the primitives to delete. Must neither be null nor empty.
144     * @throws IllegalArgumentException if dataset is null
145     * @throws IllegalArgumentException if data is null or empty
146     * @since 11240
147     */
148    public DeleteCommand(DataSet dataset, Collection<? extends OsmPrimitive> data) {
149        super(dataset);
150        CheckParameterUtil.ensureParameterNotNull(data, "data");
151        this.toDelete = data;
152        checkConsistency();
153    }
154
155    private void checkConsistency() {
156        if (toDelete.isEmpty()) {
157            throw new IllegalArgumentException(tr("At least one object to delete required, got empty collection"));
158        }
159        for (OsmPrimitive p : toDelete) {
160            if (p == null) {
161                throw new IllegalArgumentException("Primitive to delete must not be null");
162            } else if (p.getDataSet() == null) {
163                throw new IllegalArgumentException("Primitive to delete must be in a dataset");
164            }
165        }
166    }
167
168    @Override
169    public boolean executeCommand() {
170        // Make copy and remove all references (to prevent inconsistent dataset (delete referenced) while command is executed)
171        for (OsmPrimitive osm: toDelete) {
172            if (osm.isDeleted())
173                throw new IllegalArgumentException(osm + " is already deleted");
174            clonedPrimitives.put(osm, osm.save());
175
176            if (osm instanceof Way) {
177                ((Way) osm).setNodes(null);
178            } else if (osm instanceof Relation) {
179                ((Relation) osm).setMembers(null);
180            }
181        }
182
183        for (OsmPrimitive osm: toDelete) {
184            osm.setDeleted(true);
185        }
186
187        return true;
188    }
189
190    @Override
191    public void undoCommand() {
192        for (OsmPrimitive osm: toDelete) {
193            osm.setDeleted(false);
194        }
195
196        for (Entry<OsmPrimitive, PrimitiveData> entry: clonedPrimitives.entrySet()) {
197            entry.getKey().load(entry.getValue());
198        }
199    }
200
201    @Override
202    public void fillModifiedData(Collection<OsmPrimitive> modified, Collection<OsmPrimitive> deleted, Collection<OsmPrimitive> added) {
203        // Do nothing
204    }
205
206    private EnumSet<OsmPrimitiveType> getTypesToDelete() {
207        EnumSet<OsmPrimitiveType> typesToDelete = EnumSet.noneOf(OsmPrimitiveType.class);
208        for (OsmPrimitive osm : toDelete) {
209            typesToDelete.add(OsmPrimitiveType.from(osm));
210        }
211        return typesToDelete;
212    }
213
214    @Override
215    public String getDescriptionText() {
216        if (toDelete.size() == 1) {
217            OsmPrimitive primitive = toDelete.iterator().next();
218            String msg;
219            switch(OsmPrimitiveType.from(primitive)) {
220            case NODE: msg = marktr("Delete node {0}"); break;
221            case WAY: msg = marktr("Delete way {0}"); break;
222            case RELATION:msg = marktr("Delete relation {0}"); break;
223            default: throw new AssertionError();
224            }
225
226            return tr(msg, primitive.getDisplayName(DefaultNameFormatter.getInstance()));
227        } else {
228            Set<OsmPrimitiveType> typesToDelete = getTypesToDelete();
229            String msg;
230            if (typesToDelete.size() > 1) {
231                msg = trn("Delete {0} object", "Delete {0} objects", toDelete.size(), toDelete.size());
232            } else {
233                OsmPrimitiveType t = typesToDelete.iterator().next();
234                switch(t) {
235                case NODE: msg = trn("Delete {0} node", "Delete {0} nodes", toDelete.size(), toDelete.size()); break;
236                case WAY: msg = trn("Delete {0} way", "Delete {0} ways", toDelete.size(), toDelete.size()); break;
237                case RELATION: msg = trn("Delete {0} relation", "Delete {0} relations", toDelete.size(), toDelete.size()); break;
238                default: throw new AssertionError();
239                }
240            }
241            return msg;
242        }
243    }
244
245    @Override
246    public Icon getDescriptionIcon() {
247        if (toDelete.size() == 1)
248            return ImageProvider.get(toDelete.iterator().next().getDisplayType());
249        Set<OsmPrimitiveType> typesToDelete = getTypesToDelete();
250        if (typesToDelete.size() > 1)
251            return ImageProvider.get("data", "object");
252        else
253            return ImageProvider.get(typesToDelete.iterator().next());
254    }
255
256    @Override public Collection<PseudoCommand> getChildren() {
257        if (toDelete.size() == 1)
258            return null;
259        else {
260            List<PseudoCommand> children = new ArrayList<>(toDelete.size());
261            for (final OsmPrimitive osm : toDelete) {
262                children.add(new DeleteChildCommand(osm));
263            }
264            return children;
265
266        }
267    }
268
269    @Override public Collection<? extends OsmPrimitive> getParticipatingPrimitives() {
270        return toDelete;
271    }
272
273    /**
274     * Delete the primitives and everything they reference.
275     *
276     * If a node is deleted, the node and all ways and relations the node is part of are deleted as well.
277     * If a way is deleted, all relations the way is member of are also deleted.
278     * If a way is deleted, only the way and no nodes are deleted.
279     *
280     * @param layer the {@link OsmDataLayer} in whose context primitives are deleted. Must not be null.
281     * @param selection The list of all object to be deleted.
282     * @param silent  Set to true if the user should not be bugged with additional dialogs
283     * @return command A command to perform the deletions, or null of there is nothing to delete.
284     * @throws IllegalArgumentException if layer is null
285     */
286    public static Command deleteWithReferences(OsmDataLayer layer, Collection<? extends OsmPrimitive> selection, boolean silent) {
287        CheckParameterUtil.ensureParameterNotNull(layer, "layer");
288        if (selection == null || selection.isEmpty()) return null;
289        Set<OsmPrimitive> parents = OsmPrimitive.getReferrer(selection);
290        parents.addAll(selection);
291
292        if (parents.isEmpty())
293            return null;
294        if (!silent && !checkAndConfirmOutlyingDelete(parents, null))
295            return null;
296        return new DeleteCommand(layer, parents);
297    }
298
299    /**
300     * Delete the primitives and everything they reference.
301     *
302     * If a node is deleted, the node and all ways and relations the node is part of are deleted as well.
303     * If a way is deleted, all relations the way is member of are also deleted.
304     * If a way is deleted, only the way and no nodes are deleted.
305     *
306     * @param layer the {@link OsmDataLayer} in whose context primitives are deleted. Must not be null.
307     * @param selection The list of all object to be deleted.
308     * @return command A command to perform the deletions, or null of there is nothing to delete.
309     * @throws IllegalArgumentException if layer is null
310     */
311    public static Command deleteWithReferences(OsmDataLayer layer, Collection<? extends OsmPrimitive> selection) {
312        return deleteWithReferences(layer, selection, false);
313    }
314
315    /**
316     * Try to delete all given primitives.
317     *
318     * If a node is used by a way, it's removed from that way. If a node or a way is used by a
319     * relation, inform the user and do not delete.
320     *
321     * If this would cause ways with less than 2 nodes to be created, delete these ways instead. If
322     * they are part of a relation, inform the user and do not delete.
323     *
324     * @param layer the {@link OsmDataLayer} in whose context the primitives are deleted
325     * @param selection the objects to delete.
326     * @return command a command to perform the deletions, or null if there is nothing to delete.
327     */
328    public static Command delete(OsmDataLayer layer, Collection<? extends OsmPrimitive> selection) {
329        return delete(layer, selection, true, false);
330    }
331
332    /**
333     * Replies the collection of nodes referred to by primitives in <code>primitivesToDelete</code> which
334     * can be deleted too. A node can be deleted if
335     * <ul>
336     *    <li>it is untagged (see {@link Node#isTagged()}</li>
337     *    <li>it is not referred to by other non-deleted primitives outside of  <code>primitivesToDelete</code></li>
338     * </ul>
339     * @param primitivesToDelete  the primitives to delete
340     * @return the collection of nodes referred to by primitives in <code>primitivesToDelete</code> which
341     * can be deleted too
342     */
343    protected static Collection<Node> computeNodesToDelete(Collection<OsmPrimitive> primitivesToDelete) {
344        Collection<Node> nodesToDelete = new HashSet<>();
345        for (Way way : OsmPrimitive.getFilteredList(primitivesToDelete, Way.class)) {
346            for (Node n : way.getNodes()) {
347                if (n.isTagged()) {
348                    continue;
349                }
350                Collection<OsmPrimitive> referringPrimitives = n.getReferrers();
351                referringPrimitives.removeAll(primitivesToDelete);
352                int count = 0;
353                for (OsmPrimitive p : referringPrimitives) {
354                    if (!p.isDeleted()) {
355                        count++;
356                    }
357                }
358                if (count == 0) {
359                    nodesToDelete.add(n);
360                }
361            }
362        }
363        return nodesToDelete;
364    }
365
366    /**
367     * Try to delete all given primitives.
368     *
369     * If a node is used by a way, it's removed from that way. If a node or a way is used by a
370     * relation, inform the user and do not delete.
371     *
372     * If this would cause ways with less than 2 nodes to be created, delete these ways instead. If
373     * they are part of a relation, inform the user and do not delete.
374     *
375     * @param layer the {@link OsmDataLayer} in whose context the primitives are deleted
376     * @param selection the objects to delete.
377     * @param alsoDeleteNodesInWay <code>true</code> if nodes should be deleted as well
378     * @return command a command to perform the deletions, or null if there is nothing to delete.
379     */
380    public static Command delete(OsmDataLayer layer, Collection<? extends OsmPrimitive> selection,
381            boolean alsoDeleteNodesInWay) {
382        return delete(layer, selection, alsoDeleteNodesInWay, false /* not silent */);
383    }
384
385    /**
386     * Try to delete all given primitives.
387     *
388     * If a node is used by a way, it's removed from that way. If a node or a way is used by a
389     * relation, inform the user and do not delete.
390     *
391     * If this would cause ways with less than 2 nodes to be created, delete these ways instead. If
392     * they are part of a relation, inform the user and do not delete.
393     *
394     * @param layer the {@link OsmDataLayer} in whose context the primitives are deleted
395     * @param selection the objects to delete.
396     * @param alsoDeleteNodesInWay <code>true</code> if nodes should be deleted as well
397     * @param silent set to true if the user should not be bugged with additional questions
398     * @return command a command to perform the deletions, or null if there is nothing to delete.
399     */
400    public static Command delete(OsmDataLayer layer, Collection<? extends OsmPrimitive> selection,
401            boolean alsoDeleteNodesInWay, boolean silent) {
402        if (selection == null || selection.isEmpty())
403            return null;
404
405        // Diamond operator does not work with Java 9 here
406        @SuppressWarnings("unused")
407        Set<OsmPrimitive> primitivesToDelete = new HashSet<OsmPrimitive>(selection);
408
409        Collection<Relation> relationsToDelete = Utils.filteredCollection(primitivesToDelete, Relation.class);
410        if (!relationsToDelete.isEmpty() && !silent && !confirmRelationDeletion(relationsToDelete))
411            return null;
412
413        if (alsoDeleteNodesInWay) {
414            // delete untagged nodes only referenced by primitives in primitivesToDelete, too
415            Collection<Node> nodesToDelete = computeNodesToDelete(primitivesToDelete);
416            primitivesToDelete.addAll(nodesToDelete);
417        }
418
419        if (!silent && !checkAndConfirmOutlyingDelete(
420                primitivesToDelete, Utils.filteredCollection(primitivesToDelete, Way.class)))
421            return null;
422
423        Collection<Way> waysToBeChanged = new HashSet<>(OsmPrimitive.getFilteredSet(OsmPrimitive.getReferrer(primitivesToDelete), Way.class));
424
425        Collection<Command> cmds = new LinkedList<>();
426        for (Way w : waysToBeChanged) {
427            Way wnew = new Way(w);
428            wnew.removeNodes(OsmPrimitive.getFilteredSet(primitivesToDelete, Node.class));
429            if (wnew.getNodesCount() < 2) {
430                primitivesToDelete.add(w);
431            } else {
432                cmds.add(new ChangeNodesCommand(w, wnew.getNodes()));
433            }
434        }
435
436        // get a confirmation that the objects to delete can be removed from their parent relations
437        //
438        if (!silent) {
439            Set<RelationToChildReference> references = RelationToChildReference.getRelationToChildReferences(primitivesToDelete);
440            references.removeIf(ref -> ref.getParent().isDeleted());
441            if (!references.isEmpty()) {
442                DeleteFromRelationConfirmationDialog dialog = DeleteFromRelationConfirmationDialog.getInstance();
443                dialog.getModel().populate(references);
444                dialog.setVisible(true);
445                if (dialog.isCanceled())
446                    return null;
447            }
448        }
449
450        // remove the objects from their parent relations
451        //
452        for (Relation cur : OsmPrimitive.getFilteredSet(OsmPrimitive.getReferrer(primitivesToDelete), Relation.class)) {
453            Relation rel = new Relation(cur);
454            rel.removeMembersFor(primitivesToDelete);
455            cmds.add(new ChangeCommand(cur, rel));
456        }
457
458        // build the delete command
459        //
460        if (!primitivesToDelete.isEmpty()) {
461            cmds.add(layer != null ? new DeleteCommand(layer, primitivesToDelete) :
462                new DeleteCommand(primitivesToDelete.iterator().next().getDataSet(), primitivesToDelete));
463        }
464
465        return new SequenceCommand(tr("Delete"), cmds);
466    }
467
468    /**
469     * Create a command that deletes a single way segment. The way may be split by this.
470     * @param layer The layer the segment is in.
471     * @param ws The way segment that should be deleted
472     * @return A matching command to safely delete that segment.
473     */
474    public static Command deleteWaySegment(OsmDataLayer layer, WaySegment ws) {
475        if (ws.way.getNodesCount() < 3)
476            return delete(layer, Collections.singleton(ws.way), false);
477
478        if (ws.way.isClosed()) {
479            // If the way is circular (first and last nodes are the same), the way shouldn't be splitted
480
481            List<Node> n = new ArrayList<>();
482
483            n.addAll(ws.way.getNodes().subList(ws.lowerIndex + 1, ws.way.getNodesCount() - 1));
484            n.addAll(ws.way.getNodes().subList(0, ws.lowerIndex + 1));
485
486            Way wnew = new Way(ws.way);
487            wnew.setNodes(n);
488
489            return new ChangeCommand(ws.way, wnew);
490        }
491
492        List<Node> n1 = new ArrayList<>();
493        List<Node> n2 = new ArrayList<>();
494
495        n1.addAll(ws.way.getNodes().subList(0, ws.lowerIndex + 1));
496        n2.addAll(ws.way.getNodes().subList(ws.lowerIndex + 1, ws.way.getNodesCount()));
497
498        Way wnew = new Way(ws.way);
499
500        if (n1.size() < 2) {
501            wnew.setNodes(n2);
502            return new ChangeCommand(ws.way, wnew);
503        } else if (n2.size() < 2) {
504            wnew.setNodes(n1);
505            return new ChangeCommand(ws.way, wnew);
506        } else {
507            SplitWayResult split = SplitWayAction.splitWay(layer, ws.way, Arrays.asList(n1, n2), Collections.<OsmPrimitive>emptyList());
508            return split != null ? split.getCommand() : null;
509        }
510    }
511
512    public static boolean checkAndConfirmOutlyingDelete(Collection<? extends OsmPrimitive> primitives,
513            Collection<? extends OsmPrimitive> ignore) {
514        return Command.checkAndConfirmOutlyingOperation("delete",
515                tr("Delete confirmation"),
516                tr("You are about to delete nodes outside of the area you have downloaded."
517                        + "<br>"
518                        + "This can cause problems because other objects (that you do not see) might use them."
519                        + "<br>"
520                        + "Do you really want to delete?"),
521                tr("You are about to delete incomplete objects."
522                        + "<br>"
523                        + "This will cause problems because you don''t see the real object."
524                        + "<br>" + "Do you really want to delete?"),
525                primitives, ignore);
526    }
527
528    private static boolean confirmRelationDeletion(Collection<Relation> relations) {
529        JPanel msg = new JPanel(new GridBagLayout());
530        msg.add(new JMultilineLabel("<html>" + trn(
531                "You are about to delete {0} relation: {1}"
532                + "<br/>"
533                + "This step is rarely necessary and cannot be undone easily after being uploaded to the server."
534                + "<br/>"
535                + "Do you really want to delete?",
536                "You are about to delete {0} relations: {1}"
537                + "<br/>"
538                + "This step is rarely necessary and cannot be undone easily after being uploaded to the server."
539                + "<br/>"
540                + "Do you really want to delete?",
541                relations.size(), relations.size(), DefaultNameFormatter.getInstance().formatAsHtmlUnorderedList(relations, 20))
542                + "</html>"));
543        return ConditionalOptionPaneUtil.showConfirmationDialog(
544                "delete_relations",
545                Main.parent,
546                msg,
547                tr("Delete relation?"),
548                JOptionPane.YES_NO_OPTION,
549                JOptionPane.QUESTION_MESSAGE,
550                JOptionPane.YES_OPTION);
551    }
552
553    @Override
554    public int hashCode() {
555        return Objects.hash(super.hashCode(), toDelete, clonedPrimitives);
556    }
557
558    @Override
559    public boolean equals(Object obj) {
560        if (this == obj) return true;
561        if (obj == null || getClass() != obj.getClass()) return false;
562        if (!super.equals(obj)) return false;
563        DeleteCommand that = (DeleteCommand) obj;
564        return Objects.equals(toDelete, that.toDelete) &&
565                Objects.equals(clonedPrimitives, that.clonedPrimitives);
566    }
567}