/*
 * Java GPX Library (jpx-3.1.0).
 * Copyright (c) 2016-2023 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.jpx;

import static java.lang.String.format;
import static java.util.Objects.requireNonNull;

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.text.NumberFormat;
import java.text.ParseException;

/**
 * Extent of something along its greatest dimension or the extent of space
 * between two objects or places. The metric system unit for this quantity is
 * "m" (metre).
 *
 * @author <a href="mailto:franz.wilhelmstoetter@gmail.com">Franz Wilhelmstötter</a>
 * @version 1.2
 * @since 1.0
 */
public final class Length
        extends Number
        implements
                Comparable<Length>,
                Serializable
{

        @Serial
        private static final long serialVersionUID = 2L;

        /**
         * Represents a given length unit.
         */
        public enum Unit {

                /**
                 * Represents a meter.
                 */
                METER(1.0),

                /**
                 * Represents a kilometer: ≙ 1,000 m.
                 */
                KILOMETER(1_000.0),

                /**
                 * Represents an inch: ≙ 0.0254 m.
                 */
                INCH(127.0/5_000.0),

                /**
                 * Represents a foot: ≙ 0.3048 m.
                 */
                FOOT(0.3048),

                /**
                 * Represents a yard: ≙ 0.9144 m.
                 */
                YARD(1_143.0/1_250.0),

                /**
                 * Represents a statute mile: ≙ 1,609.344 m.
                 */
                MILE(201_168.0/125.0),

                /**
                 * Represents a fathom: ≙ 1.853184 m.
                 */
                FATHOM(1.853184),

                /**
                 * Represents a cable: ≙ 185.3184 m.
                 */
                CABLE(185.3184),

                /**
                 * Represents a nautical mile: ≙ 1,853.184 m.
                 */
                NAUTICAL_MILE(1_853.184);

                private final double _factor;

                Unit(final double factor) {
                        _factor = factor;
                }

                /**
                 * Convert the given length value of the given {@code sourceUnit} into a
                 * length value of {@code this} length unit. The given example converts 3
                 * inches into yards.
                 *
                 * <pre>{@code
                 * final double yards = YARD.convert(3, INCH);
                 * }</pre>
                 *
                 * @param length the length value
                 * @param sourceUnit the source length unit
                 * @return the speed value of {@code this} length unit
                 */
                public double convert(final double length, final Unit sourceUnit) {
                        requireNonNull(sourceUnit);

                        if (this == sourceUnit) {
                                return length;
                        } else {
                                final double meters = length*sourceUnit._factor;
                                return meters/_factor;
                        }
                }
        }

        private final double _value;

        /**
         * Create a new {@code Length} object with the given value in meters.
         *
         * @param value the value (in meters) of the new {@code Length} object
         */
        private Length(final double value) {
                _value = value;
        }

        /**
         * Return the length in meter.
         *
         * @return the length in meter
         */
        @Override
        public double doubleValue() {
                return _value;
        }

        /**
         * Return the length in the desired unit.
         *
         * @param unit the desired length unit
         * @return the length in the desired unit
         * @throws NullPointerException if the given length {@code unit} is
         *         {@code null}
         */
        public double to(final Unit unit) {
                return unit.convert(_value, Unit.METER);
        }

        @Override
        public int intValue() {
                return (int)doubleValue();
        }

        @Override
        public long longValue() {
                return (long)doubleValue();
        }

        @Override
        public float floatValue() {
                return (float)doubleValue();
        }

        @Override
        public int compareTo(final Length other) {
                return Double.compare(_value, other._value);
        }

        @Override
        public int hashCode() {
                return Double.hashCode(_value);
        }

        @Override
        public boolean equals(final Object obj) {
                return obj == this ||
                        obj instanceof Length &&
                        Double.compare(((Length)obj)._value, _value) == 0;
        }

        @Override
        public String toString() {
                return format("%s m", _value);
        }


        /* *************************************************************************
         *  Static object creation methods
         * ************************************************************************/

        /**
         * Create a new {@code Length} object with the given length.
         *
         * @param length the length
         * @param unit the length unit
         * @return a new {@code Length} object with the given length.
         * @throws NullPointerException if the given length {@code unit} is
         *         {@code null}
         */
        public static Length of(final double length, final Unit unit) {
                requireNonNull(unit);
                return new Length(Unit.METER.convert(length, unit));
        }

        static Length parse(final String value, final NumberFormat format) {
                final Double length = parseDouble(value, format);
                return length !=  null ? Length.of(length, Unit.METER) : null;
        }

        private static Double parseDouble(
                final String value,
                final NumberFormat format
        ) {
                final String length = Strings.trim(value);

                if (length != null) {
                        try {
                                return format.parse(length).doubleValue();
                        } catch (ParseException e) {
                                throw new NumberFormatException("Unable to parse " + value);
                        }
                } else {
                        return null;
                }
        }

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

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

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

        void write(final DataOutput out) throws IOException {
                out.writeDouble(_value);
        }

        static Length read(final DataInput in) throws IOException {
                return new Length(in.readDouble());
        }

}