001    // License: GPL. For details, see LICENSE file.
002    package org.openstreetmap.josm.actions;
003    
004    import static org.openstreetmap.josm.gui.help.HelpUtil.ht;
005    import static org.openstreetmap.josm.tools.I18n.tr;
006    
007    import java.awt.event.ActionEvent;
008    import java.awt.event.KeyEvent;
009    import java.util.Collection;
010    import java.util.List;
011    
012    import org.openstreetmap.josm.data.osm.DataSet;
013    import org.openstreetmap.josm.data.osm.OsmPrimitive;
014    import org.openstreetmap.josm.data.osm.visitor.MergeSourceBuildingVisitor;
015    import org.openstreetmap.josm.gui.dialogs.LayerListDialog;
016    import org.openstreetmap.josm.gui.layer.Layer;
017    import org.openstreetmap.josm.gui.layer.OsmDataLayer;
018    import org.openstreetmap.josm.gui.util.GuiHelper;
019    import org.openstreetmap.josm.tools.ImageProvider;
020    import org.openstreetmap.josm.tools.Shortcut;
021    
022    public class MergeSelectionAction extends AbstractMergeAction {
023        public MergeSelectionAction() {
024            super(tr("Merge selection"), "dialogs/mergedown", tr("Merge the currently selected objects into another layer"),
025                Shortcut.registerShortcut("system:mergeselection", tr("Edit: {0}", tr("Merge selection")),
026                KeyEvent.VK_M, Shortcut.CTRL_SHIFT),
027                true /* register */
028            );
029            putValue("help", ht("/Action/MergeSelection"));
030        }
031    
032        public void mergeSelected(DataSet source) {
033            List<Layer> targetLayers = LayerListDialog.getInstance().getModel().getPossibleMergeTargets(getEditLayer());
034            if (targetLayers.isEmpty()) {
035                warnNoTargetLayersForSourceLayer(getEditLayer());
036                return;
037            }
038            Layer targetLayer = askTargetLayer(targetLayers);
039            if (targetLayer == null)
040                return;
041            if (getEditLayer().isUploadDiscouraged() && targetLayer instanceof OsmDataLayer && !((OsmDataLayer)targetLayer).isUploadDiscouraged() 
042                    && getEditLayer().data.getAllSelected().size() > 1) {
043                if (warnMergingUploadDiscouragedObjects(targetLayer)) {
044                    return;
045                }
046            }
047            MergeSourceBuildingVisitor builder = new MergeSourceBuildingVisitor(getEditLayer().data);
048            ((OsmDataLayer)targetLayer).mergeFrom(builder.build());
049        }
050    
051        public void actionPerformed(ActionEvent e) {
052            if (getEditLayer() == null || getEditLayer().data.getAllSelected().isEmpty())
053                return;
054            mergeSelected(getEditLayer().data);
055        }
056    
057        @Override
058        protected void updateEnabledState() {
059            if (getCurrentDataSet() == null) {
060                setEnabled(false);
061            } else {
062                updateEnabledState(getCurrentDataSet().getAllSelected());
063            }
064        }
065    
066        @Override
067        protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) {
068            setEnabled(selection != null && !selection.isEmpty());
069        }
070        
071        /**
072         * returns true if the user wants to cancel, false if they want to continue
073         */
074        public static final boolean warnMergingUploadDiscouragedObjects(Layer targetLayer) {
075            return GuiHelper.warnUser(tr("Merging too many objects with different upload policies"),
076                    "<html>" +
077                    tr("You are about to merge more than 1 object between layers ''{0}'' and ''{1}''.<br /><br />"+
078                            "<b>This is not the recommended way of merging such data</b>.<br />"+
079                            "You should instead check and merge each object, <b>one by one</b>.<br /><br />"+
080                            "Are you sure you want to continue?", getEditLayer().getName(), targetLayer.getName(), targetLayer.getName())+
081                    "</html>",
082                    ImageProvider.get("dialogs", "mergedown"), tr("Ignore this hint and merge anyway"));
083        }
084    }