/*
 * DifferentialMassProvider.java
 *
 * Copyright (c) 2002-2018 Alexei Drummond, Andrew Rambaut and Marc Suchard
 *
 * This file is part of BEAST.
 * See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership and licensing.
 *
 * BEAST 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; either version 2
 * of the License, or (at your option) any later version.
 *
 *  BEAST 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.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with BEAST; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
 * Boston, MA  02110-1301  USA
 */

package dr.evomodel.substmodel;

import dr.math.matrixAlgebra.WrappedMatrix;

/**
 * @author Marc A. Suchard
 * @author Xiang Ji
 */
public interface DifferentialMassProvider {

    double[] getDifferentialMassMatrix(double time);

    class DifferentialWrapper implements DifferentialMassProvider {


        private final DifferentiableSubstitutionModel baseModel;
        private final WrtParameter wrt;

        public DifferentialWrapper(DifferentiableSubstitutionModel baseModel,
                                   WrtParameter wrt) {
            this.baseModel = baseModel;
            this.wrt = wrt;
        }

        @Override
        public double[] getDifferentialMassMatrix(double time) {

            WrappedMatrix infinitesimalDifferentialMatrix = baseModel.getInfinitesimalDifferentialMatrix(wrt);

            return DifferentiableSubstitutionModelUtil.getDifferentialMassMatrix(time, baseModel.getDataType().getStateCount(),
                    infinitesimalDifferentialMatrix, baseModel.getEigenDecomposition());

        }

        public interface WrtParameter {

            double getRate(int switchCase);

            double getNormalizationDifferential();
        }
    }
}
