using System.Reflection;
using System.Text;
using DS.Module.Core.Exceptions;
using DS.Module.Core.Helpers;
using DS.Module.Core.Modules;
using JetBrains.Annotations;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.FileProviders;
using Microsoft.Extensions.Options;

namespace DS.Module.Core.Extensions;

/// <summary>
/// 服务集合扩展
/// </summary>
public static class ServiceCollectionExtension
{
    /// <summary>
    /// 得到注入服务
    /// </summary>
    /// <typeparam name="TType"></typeparam>
    /// <param name="services"></param>
    /// <returns></returns>
    public static TType GetService<TType>(this IServiceCollection services)
    {
        var provider = services.BuildServiceProvider();
        return provider.GetService<TType>();
    }

    /// <summary>
    /// RegisterAssemblyTypes
    /// </summary>
    /// <param name="services">services</param>
    /// <param name="assemblies">assemblies</param>
    /// <returns>services</returns>
    public static IServiceCollection RegisterAssemblyTypes(this IServiceCollection services,
        params Assembly[] assemblies)
        => RegisterAssemblyTypes(services, null, ServiceLifetime.Singleton, assemblies);

    /// <summary>
    /// RegisterAssemblyTypes
    /// </summary>
    /// <param name="services">services</param>
    /// <param name="serviceLifetime">service lifetime</param>
    /// <param name="assemblies">assemblies</param>
    /// <returns>services</returns>
    public static IServiceCollection RegisterAssemblyTypes(this IServiceCollection services,
        ServiceLifetime serviceLifetime, params Assembly[] assemblies)
        => RegisterAssemblyTypes(services, null, serviceLifetime, assemblies);

    /// <summary>
    /// RegisterAssemblyTypes
    /// </summary>
    /// <param name="services">services</param>
    /// <param name="typesFilter">filter types to register</param>
    /// <param name="assemblies">assemblies</param>
    /// <returns>services</returns>
    public static IServiceCollection RegisterAssemblyTypes(this IServiceCollection services,
        Func<Type, bool> typesFilter, params Assembly[] assemblies)
        => RegisterAssemblyTypes(services, typesFilter, ServiceLifetime.Singleton, assemblies);

    /// <summary>
    /// RegisterAssemblyTypes
    /// </summary>
    /// <param name="services">services</param>
    /// <param name="typesFilter">filter types to register</param>
    /// <param name="serviceLifetime">service lifetime</param>
    /// <param name="assemblies">assemblies</param>
    /// <returns>services</returns>
    public static IServiceCollection RegisterAssemblyTypes(this IServiceCollection services,
        Func<Type, bool> typesFilter, ServiceLifetime serviceLifetime, params Assembly[] assemblies)
    {
        if (assemblies == null || assemblies.Length == 0)
        {
            assemblies = ReflectHelper.GetAssemblies();
        }

        var types = assemblies
            .Select(assembly => assembly.GetExportedTypes())
            .SelectMany(t => t);
        if (typesFilter != null)
        {
            types = types.Where(typesFilter);
        }

        foreach (var type in types)
        {
            services.Add(new ServiceDescriptor(type, type, serviceLifetime));
        }

        return services;
    }

    /// <summary>
    /// RegisterTypeAsImplementedInterfaces
    /// </summary>
    /// <param name="services">services</param>
    /// <param name="assemblies">assemblies</param>
    /// <returns>services</returns>
    public static IServiceCollection RegisterAssemblyTypesAsImplementedInterfaces(this IServiceCollection services,
        params Assembly[] assemblies)
        => RegisterAssemblyTypesAsImplementedInterfaces(services, typesFilter: null, ServiceLifetime.Singleton,
            assemblies);

    /// <summary>
    /// RegisterTypeAsImplementedInterfaces
    /// </summary>
    /// <param name="services">services</param>
    /// <param name="serviceLifetime">service lifetime</param>
    /// <param name="assemblies">assemblies</param>
    /// <returns>services</returns>
    public static IServiceCollection RegisterAssemblyTypesAsImplementedInterfaces(this IServiceCollection services,
        ServiceLifetime serviceLifetime, params Assembly[] assemblies)
        => RegisterAssemblyTypesAsImplementedInterfaces(services, typesFilter: null, serviceLifetime, assemblies);

    /// <summary>
    /// RegisterTypeAsImplementedInterfaces, singleton by default
    /// </summary>
    /// <param name="services">services</param>
    /// <param name="typesFilter">filter types to register</param>
    /// <param name="assemblies">assemblies</param>
    /// <returns>services</returns>
    public static IServiceCollection RegisterAssemblyTypesAsImplementedInterfaces(this IServiceCollection services,
        Func<Type, bool> typesFilter, params Assembly[] assemblies)
        => RegisterAssemblyTypesAsImplementedInterfaces(services, typesFilter: typesFilter, ServiceLifetime.Singleton,
            assemblies);

    /// <summary>
    /// RegisterTypeAsImplementedInterfaces
    /// </summary>
    /// <param name="services">services</param>
    /// <param name="typesFilter">filter types to register</param>
    /// <param name="serviceLifetime">service lifetime</param>
    /// <param name="assemblies">assemblies</param>
    /// <returns>services</returns>
    public static IServiceCollection RegisterAssemblyTypesAsImplementedInterfaces(this IServiceCollection services,
        Func<Type, bool> typesFilter, ServiceLifetime serviceLifetime, params Assembly[] assemblies)
    {
        if (assemblies == null || assemblies.Length == 0)
        {
            assemblies = ReflectHelper.GetAssemblies();
        }

        var types = assemblies
            .Select(assembly => assembly.GetExportedTypes())
            .SelectMany(t => t);
        if (typesFilter != null)
        {
            types = types.Where(typesFilter);
        }

        foreach (var type in types)
        {
            foreach (var implementedInterface in type.GetImplementedInterfaces())
            {
                services.Add(new ServiceDescriptor(implementedInterface, type, serviceLifetime));
            }
        }

        return services;
    }

    /// <summary>
    /// RegisterTypeAsImplementedInterfaces
    /// </summary>
    /// <param name="services">services</param>
    /// <param name="type">type</param>
    /// <param name="serviceLifetime">service lifetime</param>
    /// <returns>services</returns>
    public static IServiceCollection RegisterTypeAsImplementedInterfaces(this IServiceCollection services, Type type,
        ServiceLifetime serviceLifetime = ServiceLifetime.Singleton)
    {
        if (type != null)
        {
            foreach (var interfaceType in type.GetImplementedInterfaces())
            {
                services.Add(new ServiceDescriptor(interfaceType, type, serviceLifetime));
            }
        }

        return services;
    }

    /// <summary>
    /// 得到注入服务
    /// </summary>
    /// <typeparam name="TType"></typeparam>
    /// <param name="services"></param>
    /// <returns></returns>
    public static TType GetBuildService<TType>(this IServiceCollection services)
    {
        var provider = services.BuildServiceProvider();
        return provider.GetService<TType>();
    }

    /// <summary>
    /// 得到或添加Singleton服务
    /// </summary>
    /// <typeparam name="TServiceType"></typeparam>
    /// <typeparam name="TImplementation"></typeparam>
    /// <param name="services"></param>
    /// <returns></returns>
    public static TServiceType GetOrAddSingletonService<TServiceType, TImplementation>(this IServiceCollection services)
        where TServiceType : class
        where TImplementation : class, TServiceType
    {
        var type = services.GetSingletonInstanceOrNull<TServiceType>();
        if (type is null)
        {
            var provider = services.BuildServiceProvider();
            var serviceType = (TServiceType)provider.GetInstance(new ServiceDescriptor(typeof(TServiceType),
                typeof(TImplementation), ServiceLifetime.Singleton));
            return serviceType;
        }

        return type;
    }

    /// <summary>
    /// 得到或添加Singleton服务
    /// </summary>
    /// <typeparam name="TServiceType"></typeparam>
    public static TServiceType GetOrAddSingletonService<TServiceType>(this IServiceCollection services,
        Func<TServiceType> factory) where TServiceType : class
    {
        var servciceType = services.GetSingletonInstanceOrNull<TServiceType>();
        if (servciceType is null)
        {
            servciceType = factory();
            services.AddSingleton<TServiceType>(servciceType);
        }

        return servciceType;
    }

    public static IConfiguration GetConfiguration(this IServiceCollection services)
    {
        return services.GetBuildService<IConfiguration>();
    }

    /// <summary>
    /// 获取单例注册服务对象
    /// </summary>
    public static T GetSingletonInstanceOrNull<T>(this IServiceCollection services)
    {
        ServiceDescriptor descriptor =
            services.FirstOrDefault(d => d.ServiceType == typeof(T) && d.Lifetime == ServiceLifetime.Singleton);

        if (descriptor?.ImplementationInstance != null)
        {
            return (T)descriptor.ImplementationInstance;
        }

        if (descriptor?.ImplementationFactory != null)
        {
            return (T)descriptor.ImplementationFactory.Invoke(null);
        }

        return default;
    }

    // /// <summary>
    // /// 得到操作设置
    // /// </summary>
    // /// <param name="services"></param>
    // /// <returns></returns>
    // public static AppOptionSettings GetAppSettings(this IServiceCollection services)
    // {
    //     services.NotNull(nameof(services));
    //     return services.GetBuildService<IOptions<AppOptionSettings>>()?.Value;
    // }

    public static T GetSingletonInstance<T>(this IServiceCollection services)
    {
        var service = services.GetSingletonInstanceOrNull<T>();
        if (service == null)
        {
            throw new InvalidOperationException("找不到singleton服务: " + typeof(T).AssemblyQualifiedName);
        }

        return service;
    }

    #region New Module

    public static ObjectAccessor<T> TryAddObjectAccessor<T>(this IServiceCollection services)
    {
        if (services.Any(s => s.ServiceType == typeof(ObjectAccessor<T>)))
        {
            return services.GetSingletonInstance<ObjectAccessor<T>>();
        }

        return services.AddObjectAccessor<T>();
    }

    public static ObjectAccessor<T> AddObjectAccessor<T>(this IServiceCollection services)
    {
        return services.AddObjectAccessor(new ObjectAccessor<T>());
    }

    public static ObjectAccessor<T> AddObjectAccessor<T>(this IServiceCollection services, T obj)
    {
        return services.AddObjectAccessor(new ObjectAccessor<T>(obj));
    }

    public static ObjectAccessor<T> AddObjectAccessor<T>(this IServiceCollection services, ObjectAccessor<T> accessor)
    {
        if (services.Any(s => s.ServiceType == typeof(ObjectAccessor<T>)))
        {
            throw new Exception("在类型“{typeof(T).AssemblyQualifiedName)}”之前注册了对象: ");
        }

        //Add to the beginning for fast retrieve
        services.Insert(0, ServiceDescriptor.Singleton(typeof(ObjectAccessor<T>), accessor));
        services.Insert(0, ServiceDescriptor.Singleton(typeof(IObjectAccessor<T>), accessor));

        return accessor;
    }

    public static T GetObjectOrNull<T>(this IServiceCollection services)
        where T : class
    {
        return services.GetSingletonInstanceOrNull<IObjectAccessor<T>>()?.Value;
    }

    public static T GetObject<T>(this IServiceCollection services)
        where T : class
    {
        return services.GetObjectOrNull<T>() ??
               throw new Exception($"找不到的对象 {typeof(T).AssemblyQualifiedName} 服务。请确保您以前使用过AddObjectAccessor！");
    }

    public static IServiceProvider BuildServiceProviderFromFactory([NotNull] this IServiceCollection services)
    {
        foreach (var service in services)
        {
            var factoryInterface = service.ImplementationInstance?.GetType()
                .GetTypeInfo()
                .GetInterfaces()
                .FirstOrDefault(i => i.GetTypeInfo().IsGenericType &&
                                     i.GetGenericTypeDefinition() == typeof(IServiceProviderFactory<>));

            if (factoryInterface == null)
            {
                continue;
            }

            var containerBuilderType = factoryInterface.GenericTypeArguments[0];
            return (IServiceProvider)typeof(Extensions)
                .GetTypeInfo()
                .GetMethods()
                .Single(m => m.Name == nameof(BuildServiceProviderFromFactory) && m.IsGenericMethod)
                .MakeGenericMethod(containerBuilderType)
                .Invoke(null, new object[] { services, null });
        }

        return services.BuildServiceProvider();
    }

    #endregion New Module

    /// <summary>
    /// 得到文件容器
    /// </summary>
    /// <param name="services">服务接口</param>
    /// <param name="fileName">文件名+后缀名</param>
    /// <param name="fileNotExistsMsg">文件不存提示信息</param>
    /// <returns>返回文件中的文件</returns>
    public static string GetFileText(this IServiceCollection services, string fileName, string fileNotExistsMsg)
    {
        fileName.NotNullOrEmpty(nameof(fileName));
        var fileProvider = services.GetSingletonInstanceOrNull<IFileProvider>();

        if (fileProvider == null)
        {
            throw new DSAppException("IFileProvider接口不存在");
        }


        var fileInfo = fileProvider.GetFileInfo(fileName);
        if (!fileInfo.Exists)
        {
            if (!fileNotExistsMsg.IsNullOrEmpty())
            {
                throw new DSAppException(fileNotExistsMsg);
            }
        }

        var text = ReadAllText(fileInfo);
        if (text.IsNullOrEmpty())
        {
            throw new DSAppException("文件内容不存在");
        }

        return text;
    }

    /// <summary>
    /// 根据配置得到文件内容
    /// </summary>
    /// <param name="services">服务接口</param>
    /// <param name="sectionKey">分区键</param>
    /// <param name="fileNotExistsMsg">文件不存提示信息</param>
    /// <returns>返回文件中的文件</returns>
    public static string GetFileByConfiguration(this IServiceCollection services, string sectionKey,
        string fileNotExistsMsg)
    {
        sectionKey.NotNullOrEmpty(nameof(sectionKey));
        var configuration = services.GetService<IConfiguration>();
        var value = configuration?.GetSection(sectionKey)?.Value;
        return services.GetFileText(value, fileNotExistsMsg);
    }

    /// <summary>
    /// 读取全部文本
    /// </summary>
    /// <param name="fileInfo">文件信息接口</param>
    /// <returns></returns>
    private static string ReadAllText(IFileInfo fileInfo)
    {
        byte[] buffer;
        using var stream = fileInfo.CreateReadStream();
        buffer = new byte[stream.Length];
        stream.Read(buffer, 0, buffer.Length);
        return Encoding.Default.GetString(buffer).Trim();
    }

    /// <summary>
    /// 添加文件提供器
    /// </summary>
    /// <param name="services"></param>
    /// <returns></returns>
    public static IServiceCollection AddFileProvider(this IServiceCollection services)
    {
        var basePath = Microsoft.DotNet.PlatformAbstractions.ApplicationEnvironment.ApplicationBasePath; //获取项目路径
        return services.AddSingleton<IFileProvider>(new PhysicalFileProvider(basePath));
    }

    /// <summary>
    /// 获取指定key的值,如没有则设置并获取默认值
    /// </summary>
    /// <typeparam name="TKey">key的类型</typeparam>
    /// <typeparam name="TValue">value的类型</typeparam>
    /// <param name="dict">字典</param>
    /// <param name="key">key</param>
    /// <param name="func">默认值委托</param>
    /// <returns></returns>
    public static TValue GetOrAdd<TKey, TValue>(this IDictionary<TKey, TValue> dict, TKey key, Func<TKey, TValue> func)
    {
        if (dict.TryGetValue(key, out var obj))
        {
            return obj;
        }

        return dict[key] = func(key);
    }
}