sdks/dotnet/basyx-core/BaSyx.Models/Core/Common/ValueObject.cs

/*******************************************************************************
* Copyright (c) 2020 Robert Bosch GmbH
* Author: Constantin Ziesche (constantin.ziesche@bosch.com)
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0
*
* SPDX-License-Identifier: EPL-2.0
*******************************************************************************/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace BaSyx.Models.Core.Common
{
    public abstract class ValueObject
    {
        protected abstract IEnumerable<object> GetEqualityComponents();
        public override bool Equals(object obj)
        {
            if (obj == null)
                return false;

            if (GetType() != obj.GetType())
                return false;

            var valueObject = (ValueObject)obj;

            return GetEqualityComponents().SequenceEqual(valueObject.GetEqualityComponents());
        }

        public override int GetHashCode()
        {
            return GetEqualityComponents()
                .Aggregate(1, (current, obj) =>
                {
                    unchecked
                    {
                        return current * 23 + (obj?.GetHashCode() ?? 0);
                    }
                });
        }

        public static bool operator ==(ValueObject a, ValueObject b)
        {
            if (a is null && b is null)
                return true;

            if (a is null || b is null)
                return false;

            return a.Equals(b);
        }

        public static bool operator !=(ValueObject a, ValueObject b)
        {
            return !(a == b);
        }
    }
}