using System;
using System.Collections.Generic;
using ModestTree;

namespace Zenject
{
    [NoReflectionBaking]
    public class ScopableBindingFinalizer : ProviderBindingFinalizer
    {
        readonly Func<DiContainer, Type, IProvider> _providerFactory;

        public ScopableBindingFinalizer(
            BindInfo bindInfo, Func<DiContainer, Type, IProvider> providerFactory)
            : base(bindInfo)
        {
            _providerFactory = providerFactory;
        }

        protected override void OnFinalizeBinding(DiContainer container)
        {
            if (BindInfo.ToChoice == ToChoices.Self)
            {
                Assert.IsEmpty(BindInfo.ToTypes);
                FinalizeBindingSelf(container);
            }
            else
            {
                FinalizeBindingConcrete(container, BindInfo.ToTypes);
            }
        }

        void FinalizeBindingConcrete(DiContainer container, List<Type> concreteTypes)
        {
            if (concreteTypes.Count == 0)
            {
                // This can be common when using convention based bindings
                return;
            }

            var scope = GetScope();
            switch (scope)
            {
                case ScopeTypes.Transient:
                {
                    RegisterProvidersForAllContractsPerConcreteType(
                        container, concreteTypes, _providerFactory);
                    break;
                }
                case ScopeTypes.Singleton:
                {
                    RegisterProvidersForAllContractsPerConcreteType(
                        container,
                        concreteTypes,
                        (_, concreteType) =>
                            BindingUtil.CreateCachedProvider(
                                _providerFactory(container, concreteType)));
                    break;
                }
                default:
                {
                    throw Assert.CreateException();
                }
            }
        }

        void FinalizeBindingSelf(DiContainer container)
        {
            var scope = GetScope();

            switch (scope)
            {
                case ScopeTypes.Transient:
                {
                    RegisterProviderPerContract(container, _providerFactory);
                    break;
                }
                case ScopeTypes.Singleton:
                {
                    RegisterProviderPerContract(
                        container,
                        (_, contractType) =>
                            BindingUtil.CreateCachedProvider(
                                _providerFactory(container, contractType)));
                    break;
                }
                default:
                {
                    throw Assert.CreateException();
                }
            }
        }
    }
}