// Copyright (C) Stichting Deltares 2025. All rights reserved.
// 
// This file is part of the Dam Engine.
// 
// The Dam Engine is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero 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 Affero General Public License for more details.
// 
// You should have received a copy of the GNU Affero 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.That(result, Is.True);

        result = referenceComparer.Equals(doubleValue2.GetType(), intValue1.GetType());
        Assert.That(result, Is.False);

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

        const double testDouble = new double();

        result = referenceComparer.Equals(testPoint1.GetType(), testPoint2.GetType());
        Assert.That(result, Is.True);

        result = referenceComparer.Equals(testDouble.GetType(), testPoint1.GetType());
        Assert.That(result, Is.False);
    }

    /// <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.That(hashCode3, Is.EqualTo(hashCode2));
        Assert.That(hashCode4, Is.Not.EqualTo(hashCode2));
        Assert.That(hashCode5, Is.EqualTo(hashCode2));

        // 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
        };
        ObjectCopierTest.TestPoint geometryPoint4 = geometryPoint1;

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

        // compare
        Assert.That(hashCode2, Is.Not.EqualTo(hashCode1));
        Assert.That(hashCode3, Is.Not.EqualTo(hashCode1));
        Assert.That(hashCode4, Is.EqualTo(hashCode1));
    }
}