// Copyright (C) Stichting Deltares 2018. All rights reserved.
//
// This file is part of the Delta Shell Light Library.
//
// The Delta Shell Light Library is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// 
// This program 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
//
// All names, logos, and references to "Deltares" are registered trademarks of
// Stichting Deltares and remain full property of Stichting Deltares at all times.
// All rights reserved.

using Deltares.DamEngine.Data.Standard;
using NUnit.Framework;

namespace Deltares.DamEngine.Data.Tests.Standard
{
    /// <summary>
    /// Tests to check the reference equality comparer
    /// </summary>
    [TestFixture]
    public class ReferenceEqualityComparerTest
    {
        /// <summary>
        /// Test for object comparer.
        /// </summary>
        [Test]
        public void EqualsTest()
        {
            var referenceComparer = new ReferenceEqualityComparer();

            const double doubleValue1 = 1;
            const double doubleValue2 = 5;
            const int intValue1 = 1;

            bool result = referenceComparer.Equals(doubleValue1.GetType(), doubleValue2.GetType());

            Assert.IsTrue(result);

            result = referenceComparer.Equals(doubleValue2.GetType(), intValue1.GetType());
            Assert.IsFalse(result);


            var testPoint1 = new ObjectCopierTest.TestPoint();
            var testPoint2 = new ObjectCopierTest.TestPoint();

            const double testDouble = new double();

            result = referenceComparer.Equals(testPoint1.GetType(), testPoint2.GetType());
            Assert.IsTrue(result);

            result = referenceComparer.Equals(testDouble.GetType(), testPoint1.GetType());
            Assert.IsFalse(result);
        }

        /// <summary>
        /// Test for GetHashCode.
        /// </summary>
        [Test]
        public void GetHashCodeTest()
        {
            // initialise constants
            var comparer = new ReferenceEqualityComparer();

            const double doubleValue1 = 1;
            const double doubleValue2 = doubleValue1;
            const double doubleValue3 = doubleValue1;
            const double doubleValue4 = 2;
            const double doubleValue5 = 1;

            // get hash codes
            int hashCode2 = comparer.GetHashCode(doubleValue2);
            int hashCode3 = comparer.GetHashCode(doubleValue3);
            int hashCode4 = comparer.GetHashCode(doubleValue4);
            int hashCode5 = comparer.GetHashCode(doubleValue5);

            // compare
            Assert.AreEqual(hashCode2, hashCode3);
            Assert.AreNotEqual(hashCode2, hashCode4);
            Assert.AreEqual(hashCode2, hashCode5);


            // initialise geometry points
            var geometryPoint1 = new ObjectCopierTest.TestPoint { X = 1, Z = 1 };
            var geometryPoint2 = new ObjectCopierTest.TestPoint { X = 1, Z = 1 };
            var geometryPoint3 = new ObjectCopierTest.TestPoint { X = 1, Z = 99 };
            var geometryPoint4 = geometryPoint1;

            // get hash codes
            int hashCode1 = comparer.GetHashCode(geometryPoint1);
            hashCode2 = comparer.GetHashCode(geometryPoint2);
            hashCode3 = comparer.GetHashCode(geometryPoint3);
            hashCode4 = comparer.GetHashCode(geometryPoint4);

            // compare
            Assert.AreNotEqual(hashCode1, hashCode2);
            Assert.AreNotEqual(hashCode1, hashCode3);
            Assert.AreEqual(hashCode1, hashCode4);
        }
    }
}