CatalogMapMoveListenerProvider.java

/**
 *
 *    geo-platform
 *    Rich webgis framework
 *    http://geo-platform.org
 *   ====================================================================
 *
 *   Copyright (C) 2008-2017 geoSDI Group (CNR IMAA - Potenza - ITALY).
 *
 *   This program is free software: you can redistribute it and/or modify it
 *   under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version. This program is distributed in the
 *   hope that it will be useful, but WITHOUT ANY WARRANTY; without
 *   even the implied warranty of MERCHANTABILITY or FITNESS FOR
 *   A PARTICULAR PURPOSE. See the GNU General Public License
 *   for more details. You should have received a copy of the GNU General
 *   Public License along with this program. If not, see http://www.gnu.org/licenses/
 *
 *   ====================================================================
 *
 *   Linking this library statically or dynamically with other modules is
 *   making a combined work based on this library. Thus, the terms and
 *   conditions of the GNU General Public License cover the whole combination.
 *
 *   As a special exception, the copyright holders of this library give you permission
 *   to link this library with independent modules to produce an executable, regardless
 *   of the license terms of these independent modules, and to copy and distribute
 *   the resulting executable under terms of your choice, provided that you also meet,
 *   for each linked independent module, the terms and conditions of the license of
 *   that module. An independent module is a module which is not derived from or
 *   based on this library. If you modify this library, you may extend this exception
 *   to your version of the library, but you are not obligated to do so. If you do not
 *   wish to do so, delete this exception statement from your version.
 */
package org.geosdi.geoplatform.gui.client.config.provider;

import javax.inject.Inject;
import javax.inject.Provider;
import org.geosdi.geoplatform.gui.client.puregwt.event.CatalogBBoxChangeEvent;
import org.geosdi.geoplatform.gui.configuration.map.client.GPCoordinateReferenceSystem;
import org.geosdi.geoplatform.gui.puregwt.GPEventBus;
import org.gwtopenmaps.openlayers.client.Bounds;
import org.gwtopenmaps.openlayers.client.Map;
import org.gwtopenmaps.openlayers.client.Projection;
import org.gwtopenmaps.openlayers.client.event.MapMoveEndListener;
import org.gwtopenmaps.openlayers.client.event.MapMoveEndListener.MapMoveEndEvent;

/**
 *
 * @author Giuseppe La Scaleia - CNR IMAA geoSDI Group
 * @email giuseppe.lascaleia@geosdi.org
 */
public class CatalogMapMoveListenerProvider implements
        Provider<MapMoveEndListener> {

    private GPEventBus bus;
    private CatalogBBoxChangeEvent event = new CatalogBBoxChangeEvent();

    @Inject
    public CatalogMapMoveListenerProvider(GPEventBus theBus) {
        this.bus = theBus;
    }

    @Override
    public MapMoveEndListener get() {
        return new MapMoveEndListener() {
            
            @Override
            public void onMapMoveEnd(MapMoveEndEvent eventObject) {
                Map map = eventObject.getSource();
                fireCatalogBBoxChangeEvent(CatalogMapExtentReprojector.reprojects(
                        new Projection(map.getProjection()), map.getExtent()));
            }
        };
    }

    protected void fireCatalogBBoxChangeEvent(Bounds extent) {
        this.event.bind(extent);
        this.bus.fireEvent(event);
    }

    public static class CatalogMapExtentReprojector {

        private static final Projection dest = new Projection(
                GPCoordinateReferenceSystem.WGS_84.getCode());

        public static Bounds reprojects(Projection source, Bounds input) {
            return (source.getProjectionCode().equals(dest.getProjectionCode()))
                    ? input : input.transform(source, dest);
        }
    }
}