using Volo.Abp.DependencyInjection;

namespace BuildFlow.Host.Configuration;

/// <summary>
/// 注册 ABP 与 ASP.NET Core 管线之间的双向访问桥。
/// ABP 模块的 <c>OnApplicationInitialization</c> 通过 <c>context.GetApplicationBuilder()</c> /
/// <c>context.GetEndpointRouteBuilder()</c> 取回这些 ObjectAccessor，从而在 ABP 模块里装配中间件、
/// 映射 Hub 等。每个 accessor 同时注册「具体类型」与 <c>IObjectAccessor&lt;T&gt;</c> 接口两份，
/// 兼容 ABP 内部按接口解析与宿主按具体类型解析两种获取方式。
/// </summary>
public static class HostObjectAccessors
{
    public static IServiceCollection AddHostObjectAccessors(this IServiceCollection services)
    {
        services.AddAccessor(new ObjectAccessor<IApplicationBuilder>());
        services.AddAccessor(new ObjectAccessor<WebApplication>());
        services.AddAccessor(new ObjectAccessor<IHost>());
        services.AddAccessor(new ObjectAccessor<IEndpointRouteBuilder>());
        return services;
    }

    /// <summary>同时注册 accessor 的具体类型与 <see cref="IObjectAccessor{T}"/> 接口，单一注册点避免重复。</summary>
    private static void AddAccessor<T>(this IServiceCollection services, ObjectAccessor<T> accessor)
        where T : class
    {
        services.AddSingleton(accessor);
        services.AddSingleton<IObjectAccessor<T>>(accessor);
    }
}