/*
 * Java Genetic Algorithm Library (jenetics-7.2.0).
 * Copyright (c) 2007-2023 Franz Wilhelmstötter
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Author:
 *    Franz Wilhelmstötter (franz.wilhelmstoetter@gmail.com)
 */
package io.jenetics.ext;

import static io.jenetics.internal.util.SerialIO.readBytes;
import static io.jenetics.internal.util.SerialIO.readInt;
import static io.jenetics.internal.util.SerialIO.writeBytes;
import static io.jenetics.internal.util.SerialIO.writeInt;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.Serial;
import java.io.Serializable;
import java.math.BigInteger;

import io.jenetics.AbstractChromosome;
import io.jenetics.DoubleGene;
import io.jenetics.NumericChromosome;
import io.jenetics.util.ISeq;
import io.jenetics.util.MSeq;

/**
 * Numeric chromosome implementation which holds arbitrary sized integer numbers.
 *
 * @author <a href="mailto:franz.wilhelmstoetter@gmail.com">Franz Wilhelmstötter</a>
 * @version 5.2
 * @since 3.5
 */
public class BigIntegerChromosome
        extends AbstractChromosome<BigIntegerGene>
        implements
                NumericChromosome<BigInteger, BigIntegerGene>,
                Serializable
{

        @Serial
        private static final long serialVersionUID = 1L;

        private final BigInteger _min;
        private final BigInteger _max;

        /**
         * Create a new chromosome from the given genes array.
         *
         * @param genes the genes of the new chromosome.
         * @throws IllegalArgumentException if the {@code genes.length()} is smaller
         *         than one.
         * @throws NullPointerException if the {@code genes} are {@code null}.
         * @throws IllegalArgumentException if the gene sequence is empty
         */
        protected BigIntegerChromosome(final ISeq<BigIntegerGene> genes) {
                super(genes);
                _min = genes.get(0).min();
                _max = genes.get(0).max();
        }

        /**
         * Create a new random {@code BigIntegerChromosome} with the given
         * {@code length}.
         *
         * @param min the min value of the {@link BigIntegerGene}s (inclusively).
         * @param max the max value of the {@link BigIntegerGene}s (exclusively).
         * @param length the length of the chromosome.
         * @throws NullPointerException if one of the arguments is {@code null}.
         * @throws IllegalArgumentException if the {@code length} is smaller than
         *         one.
         */
        public BigIntegerChromosome(
                final BigInteger min,
                final BigInteger max,
                final int length
        ) {
                this(BigIntegerGene.seq(min, max, length));
                _valid = true;
        }

        /**
         * Create a new random {@code DoubleChromosome} of length one.
         *
         * @param min the minimal value of this chromosome (inclusively).
         * @param max the maximal value of this chromosome (exclusively).
         * @throws NullPointerException if one of the arguments is {@code null}.
         */
        public BigIntegerChromosome(final BigInteger min, final BigInteger max) {
                this(min, max, 1);
        }

        @Override
        public BigInteger min() {
                return _min;
        }

        @Override
        public BigInteger max() {
                return _max;
        }

        @Override
        public BigIntegerChromosome newInstance(final ISeq<BigIntegerGene> genes) {
                return new BigIntegerChromosome(genes);
        }

        @Override
        public BigIntegerChromosome newInstance() {
                return new BigIntegerChromosome(_min, _max, length());
        }

        /* *************************************************************************
         * Static factory methods.
         **************************************************************************/

        /**
         * Create a new {@code DoubleChromosome} with the given genes.
         *
         * @param genes the genes of the chromosome.
         * @return a new chromosome with the given genes.
         * @throws IllegalArgumentException if the length of the genes array is
         *         empty.
         * @throws NullPointerException if the given {@code genes} array is
         *         {@code null}
         */
        public static BigIntegerChromosome of(final BigIntegerGene... genes) {
                return new BigIntegerChromosome(ISeq.of(genes));
        }

        /**
         * Create a new random {@code DoubleChromosome}.
         *
         * @param min the min value of the {@link DoubleGene}s (inclusively).
         * @param max the max value of the {@link DoubleGene}s (exclusively).
         * @param length the length of the chromosome.
         * @return a new {@code DoubleChromosome} with the given parameter
         */
        public static BigIntegerChromosome of(final BigInteger min, BigInteger max, final int length) {
                return new BigIntegerChromosome(min, max, length);
        }

        /**
         * Create a new random {@code DoubleChromosome} of length one.
         *
         * @param min the minimal value of this chromosome (inclusively).
         * @param max the maximal value of this chromosome (exclusively).
         * @return a new {@code DoubleChromosome} with the given parameter
         */
        public static BigIntegerChromosome of(final BigInteger min, final BigInteger max) {
                return new BigIntegerChromosome(min, max);
        }

        /* *************************************************************************
         *  Java object serialization
         * ************************************************************************/

        @Serial
        private Object writeReplace() {
                return new SerialProxy(SerialProxy.BIG_INTEGER_CHROMOSOME, this);
        }

        @Serial
        private void readObject(final ObjectInputStream stream)
                throws InvalidObjectException
        {
                throw new InvalidObjectException("Serialization proxy required.");
        }

        void write(final DataOutput out) throws IOException {
                writeInt(length(), out);
                writeBytes(_min.toByteArray(), out);
                writeBytes(_max.toByteArray(), out);

                for (BigIntegerGene gene : _genes) {
                        writeBytes(gene.allele().toByteArray(), out);
                }
        }

        static BigIntegerChromosome read(final DataInput in) throws IOException {
                final var length = readInt(in);
                final var min = new BigInteger(readBytes(in));
                final var max = new BigInteger(readBytes(in));

                final MSeq<BigIntegerGene> genes = MSeq.ofLength(length);
                for (int i = 0; i < length; ++i) {
                        final BigInteger value = new BigInteger(readBytes(in));
                        genes.set(i, BigIntegerGene.of(value, min, max));
                }

                return new BigIntegerChromosome(genes.toISeq());
        }

}