source: josm/trunk/src/org/openstreetmap/josm/actions/PasteTagsAction.java@ 729

// License: GPL. Copyright 2007 by Immanuel Scholz and others
// Author: David Earl
package org.openstreetmap.josm.actions;

import static org.openstreetmap.josm.tools.I18n.tr;

import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.Map;

import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.command.ChangePropertyCommand;
import org.openstreetmap.josm.command.Command;
import org.openstreetmap.josm.command.SequenceCommand;
import org.openstreetmap.josm.data.SelectionChangedListener;
import org.openstreetmap.josm.data.osm.DataSet;
import org.openstreetmap.josm.data.osm.OsmPrimitive;

public final class PasteTagsAction extends JosmAction implements SelectionChangedListener {

    public PasteTagsAction(JosmAction copyAction) {
        super(tr("Paste Tags"), "pastetags",
                        tr("Apply tags of contents of paste buffer to all selected items."),
                        KeyEvent.VK_V, KeyEvent.CTRL_MASK | KeyEvent.SHIFT_MASK, true);
                DataSet.selListeners.add(this);
                copyAction.addListener(this);
                setEnabled(false);
    }

    private void pasteKeys(Collection<Command> clist, Collection<? extends OsmPrimitive> pasteBufferSubset, Collection<OsmPrimitive> selectionSubset) {
                /* scan the paste buffer, and add tags to each of the selected objects. 
                 * If a tag already exists, it is overwritten */
                if (selectionSubset != null && ! selectionSubset.isEmpty()) {
                        for (Iterator<? extends OsmPrimitive> it = pasteBufferSubset.iterator(); it.hasNext();) {
                                OsmPrimitive osm = it.next();
                                for (String key : osm.keys.keySet()) {
                                        if (! key.equals("created_by"))
                                                clist.add(new ChangePropertyCommand(selectionSubset, key, osm.keys.get(key)));
                                }
                        }
                }       
    }
    
    public void actionPerformed(ActionEvent e) {
                Collection<Command> clist = new LinkedList<Command>();          
                pasteKeys(clist, Main.pasteBuffer.nodes, Main.ds.getSelectedNodes());
                pasteKeys(clist, Main.pasteBuffer.ways, Main.ds.getSelectedWays());
                pasteKeys(clist, Main.pasteBuffer.relations, Main.ds.getSelectedRelations());
                Main.main.undoRedo.add(new SequenceCommand(tr("Paste Tags"), clist));
                Main.ds.setSelected(Main.ds.getSelected()); // to force selection listeners, in particular the tag panel, to update
                Main.map.mapView.repaint();
    }
    
        private boolean containsSameKeysWithDifferentValues(Collection<? extends OsmPrimitive> osms) {
                Map<String,String> kvSeen = new HashMap<String,String>();
                for (Iterator<? extends OsmPrimitive> it = osms.iterator(); it.hasNext();) {
                        OsmPrimitive osm = it.next();
                        if (osm.keys == null || osm.keys.isEmpty())
                                continue;
                        for (String key : osm.keys.keySet()) {
                                if (key.equals("created_by")) // we ignore created_by
                                        continue;
                                String value = osm.keys.get(key);
                                if (! kvSeen.containsKey(key))
                                        kvSeen.put(key, value);
                                else if (! kvSeen.get(key).equals(value))
                                        return true;
                        }
                }               
                return false;
        }
        
        /**
         * Determines whether to enable the widget depending on the contents of the paste 
         * buffer and current selection 
         * @param pasteBuffer
         */
        private void possiblyEnable(Collection<? extends OsmPrimitive> selection, DataSet pasteBuffer) {
                /* only enable if there is something selected to paste into and 
                        if we don't have conflicting keys in the pastebuffer */
                setEnabled(selection != null &&
                                ! selection.isEmpty() &&
                                ! pasteBuffer.allPrimitives().isEmpty() && 
                                (Main.ds.getSelectedNodes().isEmpty() ||
                                        ! containsSameKeysWithDifferentValues(pasteBuffer.nodes)) && 
                                (Main.ds.getSelectedWays().isEmpty() ||
                                        ! containsSameKeysWithDifferentValues(pasteBuffer.ways)) && 
                                (Main.ds.getSelectedRelations().isEmpty() ||
                                        ! containsSameKeysWithDifferentValues(pasteBuffer.relations)));
        }
        
        @Override public void pasteBufferChanged(DataSet newPasteBuffer) {
                possiblyEnable(Main.ds.getSelected(), newPasteBuffer);
        }
        
        public void selectionChanged(Collection<? extends OsmPrimitive> newSelection) {
                possiblyEnable(newSelection, Main.pasteBuffer);
        }
}