/*
 *    GeoTools - The Open Source Java GIS Toolkit
 *    http://geotools.org
 *
 *    (C) 2001-2008, 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.crs;

import java.util.Collections;
import java.util.Map;

import org.opengis.referencing.cs.AffineCS;
import org.opengis.referencing.cs.CartesianCS;
import org.opengis.referencing.datum.ImageDatum;
import org.opengis.referencing.crs.ImageCRS;
import org.geotools.referencing.AbstractReferenceSystem;


/**
 * An engineering coordinate reference system applied to locations in images. Image coordinate
 * reference systems are treated as a separate sub-type because a separate user community exists
 * for images with its own terms of reference.
 *
 * <TABLE CELLPADDING='6' BORDER='1'>
 * <TR BGCOLOR="#EEEEFF"><TH NOWRAP>Used with CS type(s)</TH></TR>
 * <TR><TD>
 *   {@link CartesianCS Cartesian},
 *   {@link AffineCS    Affine}
 * </TD></TR></TABLE>
 *
 * @since 2.1
 *
 * @source $URL$
 * @version $Id$
 * @author Martin Desruisseaux (IRD)
 */
public class DefaultImageCRS extends AbstractSingleCRS implements ImageCRS {
    /**
     * Serial number for interoperability with different versions.
     */
    private static final long serialVersionUID = 7312452786096397847L;

    /**
     * Constructs a new image CRS 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.
     *
     * @param crs The coordinate reference system to copy.
     *
     * @since 2.2
     */
    public DefaultImageCRS(final ImageCRS crs) {
        super(crs);
    }

    /**
     * Constructs an image CRS from a name.
     *
     * @param name The name.
     * @param datum The datum.
     * @param cs The coordinate system.
     */
    public DefaultImageCRS(final String     name,
                           final ImageDatum datum,
                           final AffineCS   cs)
    {
        this(Collections.singletonMap(NAME_KEY, name), datum, cs);
    }

    /**
     * Constructs an image CRS from a set of properties. The properties are given unchanged to
     * the {@linkplain AbstractReferenceSystem#AbstractReferenceSystem(Map) super-class constructor}.
     *
     * @param properties Set of properties. Should contains at least {@code "name"}.
     * @param datum The datum.
     * @param cs The coordinate system.
     */
    public DefaultImageCRS(final Map<String,?> properties,
                           final ImageDatum    datum,
                           final AffineCS      cs)
    {
        super(properties, datum, cs);
    }

    /**
     * Returns the coordinate system.
     */
    @Override
    public AffineCS getCoordinateSystem() {
        return (AffineCS) super.getCoordinateSystem();
    }

    /**
     * Returns the datum.
     */
    @Override
    public ImageDatum getDatum() {
        return (ImageDatum) super.getDatum();
    }

    /**
     * Returns a hash value for this geographic CRS.
     *
     * @return The hash code value. This value doesn't need to be the same
     *         in past or future versions of this class.
     */
    @Override
    public int hashCode() {
        return (int)serialVersionUID ^ super.hashCode();
    }
}