com.alicizax.unity.framework/Runtime/ABase/Service/Core/ServiceContractUtility.cs

using System;

namespace AlicizaX
{
    internal static class ServiceContractUtility
    {
        public static ServiceContracts Create(Type serviceType)
            => new ServiceContracts(serviceType, null);

        public static ServiceContracts Create(Type serviceType, Type contractType)
            => new ServiceContracts(serviceType, contractType);
    }

    internal readonly struct ServiceContracts
    {
        private readonly Type _serviceType;
        private readonly Type _contractType;

        public ServiceContracts(Type serviceType, Type contractType)
        {
            _serviceType = serviceType;
            _contractType = contractType;
        }

        public int Count => _contractType == null || _contractType == _serviceType ? 1 : 2;

        public Type this[int index]
        {
            get
            {
                if (index == 0) return _serviceType;
                if (index == 1 && Count == 2) return _contractType;
                throw new IndexOutOfRangeException();
            }
        }
    }
}