using Microsoft.Extensions.DependencyInjection;
using System.Collections.Generic;
using System.Data;
using System;
using System.Linq;

namespace Church.Net.WebAPI.Extensions
{
    public static class ServiceCollectionExtensions
    {
        public static IServiceCollection Remove<T>(this IServiceCollection services)
        {
            if (services.IsReadOnly)
            {
                throw new ReadOnlyException($"{nameof(services)} is read only");
            }

            var serviceDescriptors = services.Where(descriptor => descriptor.ServiceType == typeof(T));
            if (serviceDescriptors.Any())
            {
                foreach (var service in serviceDescriptors)
                {
                    services.Remove(service);

                }
            }

            return services;
        }

        public static IServiceCollection OverWriteTransient<TService, TImplementation>(this IServiceCollection services) where TService : class where TImplementation : class, TService
        {
            services.Remove<TService>();
            services.AddTransient<TService, TImplementation>();
            return services;
        }

        public static IServiceCollection OverWriteScoped<TService, TImplementation>(this IServiceCollection services) where TService : class where TImplementation : class, TService
        {
            services.Remove<TService>();
            services.AddScoped<TService, TImplementation>();
            return services;
        }
        public static IServiceCollection OverWriteSingleton<TService, TImplementation>(this IServiceCollection services) where TService : class where TImplementation : class, TService
        {
            services.Remove<TService>();
            services.AddSingleton<TService, TImplementation>();
            return services;
        }


        //public static void AddFactory<TService, TImplementation>(this IServiceCollection services)
        //where TService : class
        //where TImplementation : class, TService
        //{
        //    services.AddTransient<TService, TImplementation>();
        //    services.AddSingleton<Func<TService>>(x => () => x.GetService<TService>());
        //    services.AddSingleton<IFactory<TService>, Factory<TService>>();
        //}


        public static IServiceCollection AddMultiScoped<IService, TBaseImplementation>(this IServiceCollection services) where IService : class where TBaseImplementation : class, IService
        {
            foreach (var type in GetImplementedTypes<IService, TBaseImplementation>())
            {
                services.AddScoped(h => (IService)Activator.CreateInstance(type));
            }
            return services;
        }
        public static IServiceCollection AddMultiTransient<IService, TBaseImplementation>(this IServiceCollection services) where IService : class where TBaseImplementation : class, IService
        {
            foreach (var type in GetImplementedTypes<IService, TBaseImplementation>())
            {
                services.AddTransient(h => (IService)Activator.CreateInstance(type));
            }
            return services;
        }
        public static IServiceCollection AddMultiSingleton<IService, TBaseImplementation>(this IServiceCollection services) where IService : class where TBaseImplementation : class, IService
        {
            foreach (var type in GetImplementedTypes<IService, TBaseImplementation>())
            {
                services.AddSingleton(h => (IService)Activator.CreateInstance(type));
            }
            return services;
        }

        private static IEnumerable<Type> GetImplementedTypes<TService, TBaseImplementation>() where TBaseImplementation : class, TService
        {

            Type interfaceType = typeof(TService);
            Type baseType = typeof(TBaseImplementation);
            IEnumerable<Type> types = System.Reflection.Assembly.GetAssembly(baseType).GetTypes()
                .Where(p => !p.IsInterface && p != baseType && interfaceType.IsAssignableFrom(p));
            return types;
        }
    }

}