/*
 *    GeoTools - The Open Source Java GIS Toolkit
 *    http://geotools.org
 *
 *    (C) 2004-2008, Open Source Geospatial Foundation (OSGeo)
 *
 *    This library is free software; you can redistribute it and/or
 *    modify it under the terms of the GNU Lesser General Public
 *    License as published by the Free Software Foundation;
 *    version 2.1 of the License.
 *
 *    This library 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
 *    Lesser General Public License for more details.
 *
 *    This package contains documentation from OpenGIS specifications.
 *    OpenGIS consortium's work is fully acknowledged here.
 */
package org.geotools.referencing.cs;

import java.util.Map;
import org.opengis.referencing.cs.LinearCS;
import org.opengis.referencing.cs.CoordinateSystemAxis;
import org.opengis.geometry.MismatchedDimensionException;
import org.geotools.measure.Measure;


/**
 * A one-dimensional coordinate system that consists of the points that lie on the single axis
 * described. The associated ordinate is the distance from the specified origin to the point
 * along the axis. Example: usage of the line feature representing a road to describe points
 * on or along that road. A {@code LinearCS} shall have one
 * {@linkplain #getAxis axis}.
 *
 * <TABLE CELLPADDING='6' BORDER='1'>
 * <TR BGCOLOR="#EEEEFF"><TH NOWRAP>Used with CRS type(s)</TH></TR>
 * <TR><TD>
 *   {@link org.geotools.referencing.crs.DefaultEngineeringCRS Engineering}
 * </TD></TR></TABLE>
 *
 * @since 2.1
 *
 * @source $URL$
 * @version $Id$
 * @author Martin Desruisseaux (IRD)
 */
public class DefaultLinearCS extends AbstractCS implements LinearCS {
    /**
     * Serial number for interoperability with different versions.
     */
    private static final long serialVersionUID = -6890723478287625763L;

    /**
     * Constructs a new coordinate system with the same values than the specified one.
     * This copy constructor provides a way to wrap an arbitrary implementation into a
     * Geotools one or a user-defined one (as a subclass), usually in order to leverage
     * some implementation-specific API. This constructor performs a shallow copy,
     * i.e. the properties are not cloned.
     *
     * @since 2.2
     */
    public DefaultLinearCS(final LinearCS cs) {
        super(cs);
    }

    /**
     * Constructs a coordinate system from a name.
     *
     * @param name  The coordinate system name.
     * @param axis  The axis.
     */
    public DefaultLinearCS(final String name, final CoordinateSystemAxis axis) {
        super(name, new CoordinateSystemAxis[] {axis});
    }

    /**
     * Constructs a coordinate system from a set of properties.
     * The properties map is given unchanged to the
     * {@linkplain AbstractCS#AbstractCS(Map,CoordinateSystemAxis[]) super-class constructor}.
     *
     * @param properties Set of properties. Should contains at least {@code "name"}.
     * @param axis       The axis.
     */
    public DefaultLinearCS(final Map<String,?> properties, final CoordinateSystemAxis axis) {
        super(properties, new CoordinateSystemAxis[] {axis});
    }

    /**
     * Computes the distance between two points.
     *
     * @param  coord1 Coordinates of the first point.
     * @param  coord2 Coordinates of the second point.
     * @return The distance between {@code coord1} and {@code coord2}.
     * @throws MismatchedDimensionException if a coordinate doesn't have the expected dimension.
     */
    @Override
    public Measure distance(final double[] coord1, final double[] coord2)
            throws MismatchedDimensionException
    {
        ensureDimensionMatch("coord1", coord1);
        ensureDimensionMatch("coord2", coord2);
        return new Measure(Math.abs(coord1[0] - coord2[0]), getDistanceUnit());
    }
}