using Microsoft.Extensions.DependencyInjection;
using System;
using System.Linq;
using System.Reflection;
/// <summary>
/// 依賴注入擴(kuò)展方法集合（基于類名約定）
/// </summary>
public static class ServiceCollectionExtensions
{
    /// <summary>
    /// 自動(dòng)注冊以"Service"結(jié)尾的類（默認(rèn)Transient生命周期）
    /// </summary>
    public static IServiceCollection AutoRegisterServices(
        this IServiceCollection services,
        Assembly assembly = null)
    {
        assembly ??= Assembly.GetCallingAssembly();
        // 掃描規(guī)則：公共類、非抽象、非泛型、類名以Service結(jié)尾
        var serviceTypes = assembly.GetTypes()
            .Where(t => 
                t.IsClass && !t.IsAbstract && t.IsPublic &&
                !t.ContainsGenericParameters &&
                t.Name.EndsWith("Service", StringComparison.OrdinalIgnoreCase))
            .ToArray();
        // 注冊服務(wù)到容器
        foreach (var implType in serviceTypes)
        {
            var interfaces = implType.GetInterfaces();
            if (interfaces.Any())
            {
                // 匹配I{ClassName}接口（如UserService→IUserService）
                var matchingInterface = interfaces.FirstOrDefault(i => 
                    i.Name == "I" + implType.Name);
                if (matchingInterface != null)
                {
                    services.AddTransient(matchingInterface, implType);
                }
                else
                {
                    // 注冊到所有實(shí)現(xiàn)的接口
                    foreach (var @interface in interfaces)
                    {
                        services.AddTransient(@interface, implType);
                    }
                }
            }
            else
            {
                // 無接口時(shí)注冊自身
                services.AddTransient(implType);
            }
        }
        return services;
    }
    /// <summary>
    /// 自動(dòng)注冊以"Service"結(jié)尾的類（支持自定義生命周期）
    /// </summary>
    public static IServiceCollection AutoRegisterServices(
        this IServiceCollection services,
        ServiceLifetime lifetime,
        Assembly assembly = null)
    {
        assembly ??= Assembly.GetCallingAssembly();
        var serviceTypes = GetServiceTypes(assembly);
        foreach (var implType in serviceTypes)
        {
            var interfaces = implType.GetInterfaces();
            var descriptor = CreateServiceDescriptor(implType, interfaces, lifetime);
            services.Add(descriptor);
        }
        return services;
    }
    // 輔助方法：獲取服務(wù)類型（提取公共邏輯）
    private static Type[] GetServiceTypes(Assembly assembly) =>
        assembly.GetTypes()
            .Where(t => 
                t.IsClass && !t.IsAbstract && t.IsPublic &&
                !t.ContainsGenericParameters &&
                t.Name.EndsWith("Service", StringComparison.OrdinalIgnoreCase))
            .ToArray();
    // 輔助方法：創(chuàng)建服務(wù)描述符（提取公共邏輯）
    private static ServiceDescriptor CreateServiceDescriptor(
        Type implType, Type[] interfaces, ServiceLifetime lifetime)
    {
        if (interfaces.Any())
        {
            var matchingInterface = interfaces.FirstOrDefault(i => 
                i.Name == "I" + implType.Name);
            if (matchingInterface != null)
            {
                return new ServiceDescriptor(matchingInterface, implType, lifetime);
            }
            // 返回第一個(gè)接口（避免注冊多個(gè)描述符）
            return new ServiceDescriptor(interfaces[0], implType, lifetime);
        }
        return new ServiceDescriptor(implType, implType, lifetime);
    }
}

var builder = WebApplication.CreateBuilder(args);
// 方式1：默認(rèn)Transient（掃描調(diào)用程序集）
builder.Services.AutoRegisterServices();
// 方式2：指定Scoped生命周期
builder.Services.AutoRegisterServices(ServiceLifetime.Scoped);
// 方式3：掃描指定程序集（如業(yè)務(wù)層）
var businessAssembly = Assembly.Load("MyBusinessLayer");
builder.Services.AutoRegisterServices(ServiceLifetime.Singleton, businessAssembly);
var app = builder.Build();

// ? 示例1：接口匹配型服務(wù)
public interface IUserService { string GetInfo(); }
public class UserService : IUserService 
{
    public string GetInfo() => "User Service Running";
}
// ? 示例2：多接口實(shí)現(xiàn)服務(wù)
public interface IAuthService { void Login(); }
public interface ILogService { void WriteLog(string msg); }
public class AuthService : IAuthService, ILogService 
{
    public void Login() { /* 登錄邏輯 */ }
    public void WriteLog(string msg) { /* 日志邏輯 */ }
}
// ? 示例3：無接口自注冊服務(wù)
public class DataService 
{
    public void ProcessData() { /* 數(shù)據(jù)處理 */ }
}
// ? 示例4：不符合約定的類（不會被注冊）
public class ServiceHelper { }        // 類名不以Service結(jié)尾
public abstract class BaseService { } // 抽象類

private static ServiceLifetime GetLifetimeFromName(string className)
{
    if (className.Contains("Singleton", StringComparison.OrdinalIgnoreCase))
        return ServiceLifetime.Singleton;
    if (className.Contains("Scoped", StringComparison.OrdinalIgnoreCase))
        return ServiceLifetime.Scoped;
    return ServiceLifetime.Transient;
}

[AttributeUsage(AttributeTargets.Class)]
public class AutoRegisterAttribute : Attribute 
{
    public ServiceLifetime Lifetime { get; set; } = ServiceLifetime.Transient;
    public bool IsEnabled { get; set; } = true;
}

private static readonly object LockObj = new();
private static Type[] _cachedServiceTypes;
private static Type[] GetCachedServiceTypes(Assembly assembly)
{
    if (_cachedServiceTypes == null)
    {
        lock (LockObj)
        {
            _cachedServiceTypes = assembly.GetTypes()
                .Where(t => /* 掃描規(guī)則 */)
                .ToArray();
        }
    }
    return _cachedServiceTypes;
}

// 僅掃描當(dāng)前程序集中的服務(wù)
builder.Services.AutoRegisterServices(typeof(UserService).Assembly);

[Fact]
public void Should_Resolve_Service_By_Convention()
{
    var services = new ServiceCollection();
    services.AutoRegisterServices(typeof(IAuthService).Assembly);
    var provider = services.BuildServiceProvider();
    var service = provider.GetService<IAuthService>();
    Assert.NotNull(service);
}