/*
 * Copyright (C) 2025  Tim Zimmermann <tim@aglais.org>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.aglais.zms.ui.util;

import org.jxmapviewer.viewer.GeoPosition;

public class GeoUtil {

    /**
     * Calculates a new geographical position by offsetting the given center position
     * by the specified distances in meters to the north/south and east/west directions.
     *
     * @param center                 The original geographic position (latitude and longitude in degrees)
     * @param offsetNorthSouthMeters The offset distance in meters to move north (positive) or south (negative)
     * @param offsetEastWestMeters   The offset distance in meters to move east (positive) or west (negative)
     * @return A new GeoPosition object representing the adjusted location
     */
    public static GeoPosition offsetByMeters(GeoPosition center, double offsetNorthSouthMeters, double offsetEastWestMeters) {
        double earthRadius = 6378137.0;

        double dLat = offsetNorthSouthMeters / earthRadius;
        double dLng = offsetEastWestMeters / (earthRadius * Math.cos(Math.toRadians(center.getLatitude())));

        double newLat = center.getLatitude() + Math.toDegrees(dLat);
        double newLng = center.getLongitude() + Math.toDegrees(dLng);

        return new GeoPosition(newLat, newLng);
    }

}