Application: gvSIG desktop

/**

 * gvSIG. Desktop Geographic Information System.

 *

 * Copyright (C) 2007-2013 gvSIG Association.

 *

 * 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, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 * For any additional information, do not hesitate to contact us

 * at info AT gvsig.com, or visit our website www.gvsig.com.

 */

package org.gvsig.fmap.mapcontext.rendering.strategies;

import org.cresques.cts.ICoordTrans;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.gvsig.fmap.dal.DataSet;

import org.gvsig.fmap.dal.feature.Feature;

import org.gvsig.fmap.dal.feature.FeatureSelection;

import org.gvsig.fmap.geom.primitive.Envelope;

import org.gvsig.fmap.mapcontext.layers.FLayer;

import org.gvsig.fmap.mapcontext.layers.operations.LayersVisitor;

import org.gvsig.fmap.mapcontext.layers.operations.SingleLayer;

import org.gvsig.fmap.mapcontext.layers.vectorial.FLyrVect;

import org.gvsig.tools.dispose.DisposableIterator;

import org.gvsig.tools.exception.BaseException;

import org.gvsig.tools.visitor.NotSupportedOperationException;

/**

 * This visitor accumulates the envelope of the

 * selected geometries

 */

public class SelectedEnvelopeVisitor implements LayersVisitor {

    private static final Logger logger =

        LoggerFactory.getLogger(SelectedEnvelopeVisitor.class);

        private Envelope rectangle = null;

        public Envelope getSelectioEnvelope() {

            return rectangle;

        }

        public String getProcessDescription() {

                return "Defining rectangle to zoom from selected geometries";

        }

        public void visit(Object obj) throws BaseException {

                if (obj instanceof FLayer) {

                        this.visit((FLayer) obj);

                } else {

                    throw new NotSupportedOperationException(this, obj);

                }

        }

        public void visit(FLayer layer) throws BaseException {

                if (!(layer instanceof SingleLayer)) {

                        return;

                } else if (!layer.isActive()) {

                        return;

        } else if (!(layer instanceof FLyrVect)) {

            return;

        }

                FLyrVect lyr_vect = (FLyrVect) layer;

                BaseException be = null;

                DataSet selection = ((SingleLayer) layer).getDataStore()

                                .getSelection();

                if (selection != null && (selection instanceof FeatureSelection)) {

                    long tot_count = lyr_vect.getFeatureStore().getFeatureCount();

                    FeatureSelection fsel = (FeatureSelection) selection;

                    long sel_count = fsel.getSize();

                    if (tot_count == sel_count) {

                        try {

                            /*

                             * If all selected, use layer envelope

                             */

                            rectangle = accum(rectangle, lyr_vect.getFullEnvelope(), null);

                        } catch (CloneNotSupportedException ex) {

                    /*

                     * This should not happen because

                     * envelopes support clone 

                     */

                            logger.debug("Error while adding envelope: " + ex.getMessage(), ex);

                        }

                    } else {

                        /*

                         * We'll use this reprojection if not null

                         * to convert feature envelopes

                         */

                        ICoordTrans ct = lyr_vect.getCoordTrans();

                        DisposableIterator iter = fsel.fastIterator();

                        Feature feat = null;

                        while (iter.hasNext()) {

                            feat = (Feature) iter.next();

                            try {

                            rectangle = accum(

                                rectangle, feat.getDefaultEnvelope(), ct);

                            } catch (CloneNotSupportedException ex) {

                            /*

                             * This should not happen because

                             * envelopes support clone 

                             */

                            logger.debug("Error while adding envelope: " + ex.getMessage(), ex);

                            break;

                            }

                        }

                        iter.dispose();

                    }

                }

        }

        /**

         * Adds add_env envelope to ini_env after reprojecting add_env

         * if cotr not null

         * 

         * @param ini_env

         * @param add_env

         * @param cotr

         * @return

         */

    private Envelope accum(

        Envelope ini_env,

        Envelope add_env,

        ICoordTrans cotr) throws CloneNotSupportedException {

        if (add_env == null) {

            /*

             * Nothing to add

             */

            return ini_env;

        } else {

            if (cotr == null) {

                /*

                 * No reprojection needed

                 */

                if (ini_env == null) {

                    return add_env;

                } else {

                    Envelope resp = (Envelope) ini_env.clone(); 

                    resp.add(add_env);

                    return resp;

                }

            } else {

                /*

                 * Reproject before adding

                 */

                Envelope add_rep = (Envelope) add_env.convert(cotr).clone();

                if (ini_env == null) {

                    /*

                     * Initial was null

                     */

                    return add_rep;

                } else {

                    Envelope resp = (Envelope) ini_env.clone(); 

                    resp.add(add_rep);

                    return resp;

                }

            }

        }

    }

}