/**
 * Copyright © CENRA (2016)
 *
 * remi.clement@espaces-naturels.fr
 * 
 * This software is a multi-platform and portable application based on 
 * the scientifical toolbox to monitor wetlands. With this toolbox it’s 
 * possible to calculate indicators «RhoMéO» to monitor quality, 
 * fonctionalities and urban and agricultural pressures of wetlands. 
 * Indicators are calculated using naturalist data entered and/or imported,
 * and geographic data downloaded from a geographic server.
 * 
 * This software is governed by the CeCILL license under French law and
 * abiding by the rules of distribution of free software.  You can  use, 
 * modify and/ or redistribute the software under the terms of the CeCILL
 * license as circulated by CEA, CNRS and INRIA at the following URL
 * "http://www.cecill.info". 
 * 
 * As a counterpart to the access to the source code and  rights to copy,
 * modify and redistribute granted by the license, users are provided only
 * with a limited warranty  and the software's author,  the holder of the
 * economic rights,  and the successive licensors  have only  limited
 * liability. 
 * 
 * In this respect, the user's attention is drawn to the risks associated
 * with loading,  using,  modifying and/or developing or reproducing the
 * software by the user in light of its specific status of free software,
 * that may mean  that it is complicated to manipulate,  and  that  also
 * therefore means  that it is reserved for developers  and  experienced
 * professionals having in-depth computer knowledge. Users are therefore
 * encouraged to load and test the software's suitability as regards their
 * requirements in conditions enabling the security of their systems and/or 
 * data to be ensured and,  more generally, to use and operate it in the 
 * same conditions as regards security. 
 * 
 * The fact that you are presently reading this means that you have had
 * knowledge of the CeCILL license and that you accept its terms.
*/
package fr.cenra.rhomeo.api.result;

import fr.cenra.rhomeo.api.IdentifiedObject;
import fr.cenra.rhomeo.api.data.TrackingPoint;
import fr.cenra.rhomeo.api.process.Indicator;
import javax.measure.unit.Unit;
import javax.validation.constraints.NotNull;

/**
 * Describe a particular type of index, including its name, description, unit, etc.
 *
 * Note : Must be a Spring component
 *
 * @author Alexis Manin (Geomatys)
 *
 * @param <V> Type of index value
 * @param <B> Type of index base (Integer for a year, {@link TrackingPoint}…)
 */
public interface IndexSpi<V extends Number, B> extends IdentifiedObject, Comparable<IndexSpi> {

    /**
     *
     * @return The unit of this index value. Should never be null. If no unit is
     * defined for the value, {@link Unit#ONE} should be returned.
     */
    @NotNull
    Unit<?> getUnit();

    /**
     *
     * @return The indicator associated to this index.
     */
    @NotNull
    Indicator getIndicator();

    /**
     * Create an index initialized with given value.
     * @param value The value to set on created index.
     * @param entity The base the index is associated with. For instance an integer to represent a year, a {@link TrackingPoint}…
     * @return The created index.
     */
    @NotNull
    Index<V> createIndex(final V value, final B entity);

    /**
     * Denotes this index as a major indicator, or a minor indicator. It differs
     * from {@link Indicator#getDefaultIndex() } by the fact that multiple
     * indice types can be primary for an indicator, but only one is the default
     * index shown on dashboard.
     *
     * @return True if this spi indices are considered as main results for the
     * target indicator (see {@link #getIndicator() }. False if it describes a
     * complementary index.
     */
    default boolean isPrimary() {
        return getName().equals(getIndicator().getDefaultIndex());
    }

    @Override
    default int compareTo(IndexSpi o) {
        if (o == null) {
            return -1;
        }

        return (getIndicator() == o.getIndicator())? 0 :
                getIndicator() == null? 1 : getIndicator().compareTo(o.getIndicator());
    }
}
