/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */
package org.apache.commons.math3.util;

import junit.framework.Assert;

import org.junit.Test;

public class Decimal64Test {
    public static final double X = 1.2345;

    public static final Decimal64 PLUS_X = new Decimal64(X);

    public static final Decimal64 MINUS_X = new Decimal64(-X);

    public static final double Y = 6.789;

    public static final Decimal64 PLUS_Y = new Decimal64(Y);

    public static final Decimal64 MINUS_Y = new Decimal64(-Y);

    public static final Decimal64 PLUS_ZERO = new Decimal64(0.0);

    public static final Decimal64 MINUS_ZERO = new Decimal64(-0.0);

    @Test
    public void testAdd() {
        Decimal64 expected, actual;

        expected = new Decimal64(X + Y);
        actual = PLUS_X.add(PLUS_Y);
        Assert.assertEquals(expected, actual);
        actual = PLUS_Y.add(PLUS_X);
        Assert.assertEquals(expected, actual);

        expected = new Decimal64(X + (-Y));
        actual = PLUS_X.add(MINUS_Y);
        Assert.assertEquals(expected, actual);
        actual = MINUS_Y.add(PLUS_X);
        Assert.assertEquals(expected, actual);

        expected = new Decimal64((-X) + (-Y));
        actual = MINUS_X.add(MINUS_Y);
        Assert.assertEquals(expected, actual);
        actual = MINUS_Y.add(MINUS_X);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.POSITIVE_INFINITY;
        actual = PLUS_X.add(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY.add(PLUS_X);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.add(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY.add(MINUS_X);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY.add(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.NEGATIVE_INFINITY;
        actual = PLUS_X.add(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.add(PLUS_X);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.add(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.add(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.add(MINUS_X);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.NAN;
        actual = Decimal64.POSITIVE_INFINITY.add(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.add(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = PLUS_X.add(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.add(PLUS_X);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.add(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.add(MINUS_X);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY.add(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.add(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.add(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.add(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.add(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
    }

    @Test
    public void testSubtract() {
        Decimal64 expected, actual;

        expected = new Decimal64(X - Y);
        actual = PLUS_X.subtract(PLUS_Y);
        Assert.assertEquals(expected, actual);

        expected = new Decimal64(X - (-Y));
        actual = PLUS_X.subtract(MINUS_Y);
        Assert.assertEquals(expected, actual);

        expected = new Decimal64((-X) - Y);
        actual = MINUS_X.subtract(PLUS_Y);
        Assert.assertEquals(expected, actual);

        expected = new Decimal64((-X) - (-Y));
        actual = MINUS_X.subtract(MINUS_Y);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.NEGATIVE_INFINITY;
        actual = PLUS_X.subtract(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.subtract(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY
                .subtract(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.POSITIVE_INFINITY;
        actual = PLUS_X.subtract(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.subtract(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY
                .subtract(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.NAN;
        actual = Decimal64.POSITIVE_INFINITY
                .subtract(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY
                .subtract(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = PLUS_X.subtract(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.subtract(PLUS_X);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.subtract(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.subtract(MINUS_X);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY.subtract(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.subtract(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.subtract(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.subtract(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.subtract(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
    }

    @Test
    public void testNegate() {
        Decimal64 expected, actual;

        expected = MINUS_X;
        actual = PLUS_X.negate();
        Assert.assertEquals(expected, actual);

        expected = PLUS_X;
        actual = MINUS_X.negate();
        Assert.assertEquals(expected, actual);

        expected = MINUS_ZERO;
        actual = PLUS_ZERO.negate();
        Assert.assertEquals(expected, actual);

        expected = PLUS_ZERO;
        actual = MINUS_ZERO.negate();
        Assert.assertEquals(expected, actual);

        expected = Decimal64.POSITIVE_INFINITY;
        actual = Decimal64.NEGATIVE_INFINITY.negate();
        Assert.assertEquals(expected, actual);

        expected = Decimal64.NEGATIVE_INFINITY;
        actual = Decimal64.POSITIVE_INFINITY.negate();
        Assert.assertEquals(expected, actual);

        expected = Decimal64.NAN;
        actual = Decimal64.NAN.negate();
        Assert.assertEquals(expected, actual);
    }

    @Test
    public void testMultiply() {
        Decimal64 expected, actual;

        expected = new Decimal64(X * Y);
        actual = PLUS_X.multiply(PLUS_Y);
        Assert.assertEquals(expected, actual);
        actual = PLUS_Y.multiply(PLUS_X);
        Assert.assertEquals(expected, actual);

        expected = new Decimal64(X * (-Y));
        actual = PLUS_X.multiply(MINUS_Y);
        Assert.assertEquals(expected, actual);
        actual = MINUS_Y.multiply(PLUS_X);
        Assert.assertEquals(expected, actual);

        expected = new Decimal64((-X) * (-Y));
        actual = MINUS_X.multiply(MINUS_Y);
        Assert.assertEquals(expected, actual);
        actual = MINUS_Y.multiply(MINUS_X);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.POSITIVE_INFINITY;
        actual = PLUS_X.multiply(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY.multiply(PLUS_X);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.multiply(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.multiply(MINUS_X);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY
                .multiply(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY
                .multiply(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.NEGATIVE_INFINITY;
        actual = PLUS_X.multiply(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.multiply(PLUS_X);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.multiply(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY.multiply(MINUS_X);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY
                .multiply(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY
                .multiply(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.NAN;
        actual = PLUS_X.multiply(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.multiply(PLUS_X);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.multiply(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.multiply(MINUS_X);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY.multiply(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.multiply(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.multiply(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.multiply(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.multiply(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
    }

    @Test
    public void testDivide() {
        Decimal64 expected, actual;

        expected = new Decimal64(X / Y);
        actual = PLUS_X.divide(PLUS_Y);
        Assert.assertEquals(expected, actual);

        expected = new Decimal64(X / (-Y));
        actual = PLUS_X.divide(MINUS_Y);
        Assert.assertEquals(expected, actual);

        expected = new Decimal64((-X) / Y);
        actual = MINUS_X.divide(PLUS_Y);
        Assert.assertEquals(expected, actual);

        expected = new Decimal64((-X) / (-Y));
        actual = MINUS_X.divide(MINUS_Y);
        Assert.assertEquals(expected, actual);

        expected = PLUS_ZERO;
        actual = PLUS_X.divide(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.divide(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);

        expected = MINUS_ZERO;
        actual = MINUS_X.divide(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = PLUS_X.divide(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.POSITIVE_INFINITY;
        actual = Decimal64.POSITIVE_INFINITY.divide(PLUS_X);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.divide(MINUS_X);
        Assert.assertEquals(expected, actual);
        actual = PLUS_X.divide(PLUS_ZERO);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.divide(MINUS_ZERO);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.NEGATIVE_INFINITY;
        actual = Decimal64.POSITIVE_INFINITY.divide(MINUS_X);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.divide(PLUS_X);
        Assert.assertEquals(expected, actual);
        actual = PLUS_X.divide(MINUS_ZERO);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.divide(PLUS_ZERO);
        Assert.assertEquals(expected, actual);

        expected = Decimal64.NAN;
        actual = Decimal64.POSITIVE_INFINITY
                .divide(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY
                .divide(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY
                .divide(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY
                .divide(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = PLUS_X.divide(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.divide(PLUS_X);
        Assert.assertEquals(expected, actual);
        actual = MINUS_X.divide(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.divide(MINUS_X);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.POSITIVE_INFINITY.divide(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.divide(Decimal64.POSITIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NEGATIVE_INFINITY.divide(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.divide(Decimal64.NEGATIVE_INFINITY);
        Assert.assertEquals(expected, actual);
        actual = Decimal64.NAN.divide(Decimal64.NAN);
        Assert.assertEquals(expected, actual);
        actual = PLUS_ZERO.divide(PLUS_ZERO);
        Assert.assertEquals(expected, actual);
        actual = PLUS_ZERO.divide(MINUS_ZERO);
        Assert.assertEquals(expected, actual);
        actual = MINUS_ZERO.divide(PLUS_ZERO);
        Assert.assertEquals(expected, actual);
        actual = MINUS_ZERO.divide(MINUS_ZERO);
        Assert.assertEquals(expected, actual);
    }

    @Test
    public void testReciprocal() {
        Decimal64 expected, actual;

        expected = new Decimal64(1.0 / X);
        actual = PLUS_X.reciprocal();
        Assert.assertEquals(expected, actual);

        expected = new Decimal64(1.0 / (-X));
        actual = MINUS_X.reciprocal();
        Assert.assertEquals(expected, actual);

        expected = PLUS_ZERO;
        actual = Decimal64.POSITIVE_INFINITY.reciprocal();
        Assert.assertEquals(expected, actual);

        expected = MINUS_ZERO;
        actual = Decimal64.NEGATIVE_INFINITY.reciprocal();
        Assert.assertEquals(expected, actual);
    }

    @Test
    public void testIsInfinite() {
        Assert.assertFalse(MINUS_X.isInfinite());
        Assert.assertFalse(PLUS_X.isInfinite());
        Assert.assertFalse(MINUS_Y.isInfinite());
        Assert.assertFalse(PLUS_Y.isInfinite());
        Assert.assertFalse(Decimal64.NAN.isInfinite());

        Assert.assertTrue(Decimal64.NEGATIVE_INFINITY.isInfinite());
        Assert.assertTrue(Decimal64.POSITIVE_INFINITY.isInfinite());
    }

    @Test
    public void testIsNaN() {
        Assert.assertFalse(MINUS_X.isNaN());
        Assert.assertFalse(PLUS_X.isNaN());
        Assert.assertFalse(MINUS_Y.isNaN());
        Assert.assertFalse(PLUS_Y.isNaN());
        Assert.assertFalse(Decimal64.NEGATIVE_INFINITY.isNaN());
        Assert.assertFalse(Decimal64.POSITIVE_INFINITY.isNaN());

        Assert.assertTrue(Decimal64.NAN.isNaN());
    }
}
