using BuildFlow.Host.Configuration;
using BuildFlow.Host.Hubs;
using BuildFlow.Host.Services.BackgroundServices;
using BuildFlow.Host.Services.Integration;
using BuildFlow.Host.Services.Notifications;
using BuildFlow.Host.Services.Users;
using FastEndpoints.Swagger;
using OpenTelemetry.Metrics;
using OpenTelemetry.Resources;
using OpenTelemetry.Trace;
using BuildFlow.Shared.Api;
using BuildFlow.Shared.Infrastructure.Serialization;
using File.Application;
using File.Infrastructure;
using IM.Application;
using IM.Domain.Common;
using IM.Infrastructure;
using BuildFlow.Platform.Application;
using BuildFlow.Platform.Infrastructure.Persistence;
using Volo.Abp;
using Volo.Abp.Modularity;
using Workflow.Application;
using Workflow.Application.Engine;
using Workflow.Application.Integration;
using Workflow.Application.Notifications;
using Workflow.Infrastructure;

namespace BuildFlow.Host;


[DependsOn(
    typeof(BuildFlow.Application.RAGApplicationModule),
    typeof(BuildFlow.Infrastructure.RAGInfrastructureModule),
    typeof(PlatformApplicationModule),
    typeof(FileApplicationModule),
    typeof(FileInfrastructureModule),
    typeof(IMApplicationModule),
    typeof(IMInfrastructureModule),
    typeof(WorkflowApplicationModule),
    typeof(WorkflowInfrastructureModule))]
/// <summary>
/// BuildFlow 主 Host 的 ABP 模块。通过 [DependsOn] 聚合 platform/rag/file/im/workflow 五个业务模块的
/// Application + Infrastructure 层，统一注册跨切面基础设施（OTel/FastEndpoints/SignalR/JWT/CORS/
/// 跨模块集成接口）与中间件管道。HTTP 层（Endpoints/Hubs）已全部并入本 Host 程序集。
/// platform 模块承载用户/角色/权限/菜单/通知（原属 rag，已独立成库）。
/// </summary>
public class BuildFlowHostModule : AbpModule
{
    public override void ConfigureServices(ServiceConfigurationContext context)
    {
        var services = context.Services;
        var config = services.GetConfiguration();

        // ===== 跨切面基础设施（仅注册一次）=====
        // OpenTelemetry：统一导出 Traces + Metrics
        var otlpEndpoint = config["OpenTelemetry:OtlpEndpoint"] ?? "http://localhost:4316";
        services.AddOpenTelemetry()
            .ConfigureResource(r => r
                .AddService(serviceName: "buildflow", serviceVersion: "1.0.0"))
            .WithTracing(tracing => tracing
                .AddAspNetCoreInstrumentation()
                .AddHttpClientInstrumentation()
                .AddEntityFrameworkCoreInstrumentation()
                .AddOtlpExporter(o => o.Endpoint = new Uri(otlpEndpoint)))
            .WithMetrics(metrics => metrics
                .AddAspNetCoreInstrumentation()
                .AddHttpClientInstrumentation()
                .AddRuntimeInstrumentation()
                .AddOtlpExporter((exporter, reader) => exporter.Endpoint = new Uri(otlpEndpoint)));

        // FastEndpoints + Swagger（Endpoints 已并入本程序集，默认扫描当前程序集）
        services.AddFastEndpoints();
        services.SwaggerDocument();

        // SignalR（rag 通知 + im 聊天共用）
        services.AddSignalR();
        // im 的 DomainExceptionHubFilter 注册为全局 hub filter（统一异常信封）
        services.AddSingleton<DomainExceptionHubFilter>();

        // 当前用户上下文：各模块的 CurrentUserContext 实现
        services.AddHttpContextAccessor();
        services.AddScoped<BuildFlow.Shared.Domain.Common.ICurrentUserContext, CurrentUserContext>();
        services.AddScoped<IUserInfoService, InProcessUserInfoService>();

        // 串联：IM @AI → RAG 问答（跨模块集成，RAG 实现 IAiBotHandler 供 IM 调用）
        services.AddScoped<BuildFlow.Shared.Integration.IAiBotHandler, BuildFlow.Application.Integration.AiBotHandler>();
        // 串联：AI 对话 → 触发工作流（跨模块集成，Workflow 实现 IWorkflowTriggerService 供 RAG 调用）
        services.AddScoped<BuildFlow.Shared.Integration.IWorkflowTriggerService, WorkflowTriggerService>();

        // workflow 后台服务：超时调度 + Webhook 投递
        services.AddScoped<ProcessEngine>();
        services.Configure<NotificationOptions>(config.GetSection("Workflow:Notifications"));
        services.AddNotifications(config);
        services.AddHostedService<TimeoutSchedulerService>();
        services.AddHostedService<WebhookDispatcherService>();

        // 消息中心通知分发器（仅 rag 用）
        services.AddScoped<BuildFlow.Platform.Application.Notifications.INotificationDispatcher, SignalRNotificationDispatcher>();

        // 进程内文件存储：覆盖 rag 原有的 HTTP 版 FileStorageClient（后注册者胜出）
        services.AddScoped<BuildFlow.Domain.Interfaces.IFileStorageClient, InProcessFileStorageClient>();

        // JWT 认证 + CORS：使用共享内核扩展方法（消除重复的认证/跨域配置）
        services.AddSharedJwtAuthentication(config);
        services.AddSharedCors();

        // 响应包裹中间件配置：文件下载为二进制流式响应，必须绕过 JSON 包裹与 MemoryStream 缓冲
        services.Configure<BuildFlow.Shared.Api.ApiResponseMiddlewareOptions>(opts =>
        {
            opts.PassthroughPrefixes.Add("/api/files/download");
            // Swagger/OpenAPI 文档必须保持原始结构，不能包裹成 { code, data, message }，否则 Swagger UI 无法识别 openapi 字段。
            opts.PassthroughPrefixes.Add("/swagger");
        });
    }

    public override void OnApplicationInitialization(ApplicationInitializationContext context)
    {
        var app = context.GetApplicationBuilder();

        // 中间件管道（只装配一次，避免双重包裹）：
        //   CORS → Routing → GlobalException → gRPC ×2 → ApiResponse → Auth → AuthZ → FastEndpoints → Swagger
        app.UseCors();
        app.UseRouting();

        // 全局异常中间件（rag 版本是超集：含流式 HasStarted 守卫）
        app.UseMiddleware<GlobalExceptionMiddleware>();

        // 响应包裹中间件（rag 版本是超集：含 /api/auth/refresh 排除 + SSE 流式路径排除）
        app.UseMiddleware<ApiResponseMiddleware>();

        app.UseAuthentication();
        app.UseAuthorization();

        app.UseFastEndpoints(config =>
        {
            config.Endpoints.RoutePrefix = "api";
            // 统一数据规范：时间字段输出 UTC 毫秒时间戳
            config.Serializer.Options.Converters.Add(new TimestampDateTimeConverter());
            config.Serializer.Options.Converters.Add(new TimestampDateTimeOffsetConverter());

            // 校验失败统一 { code:400, message, data:null }（使用内核共享信封类型）
            config.Errors.StatusCode = 400;
            config.Errors.ResponseBuilder = (failures, ctx, statusCode) =>
            {
                var message = string.Join("; ", failures.Select(f => f.ErrorMessage));
                return new BuildFlow.Shared.Api.ValidationErrorResponse(400, message);
            };

            // 全局异常过滤器：扩展为同时识别 rag 与 file-system 两套领域异常
            config.Endpoints.Configurator = ep =>
            {
                ep.PostProcessors(Order.After, typeof(AggregateExceptionHandler<,>));
            };
        });

        app.UseSwaggerGen();

        // SignalR Hub（rag 通知 + im 聊天，不同路径共存）
        context.GetEndpointRouteBuilder().MapHub<NotificationHub>("/hubs/notifications");
        context.GetEndpointRouteBuilder().MapHub<ChatHub>("/hubs/chat");
    }
}

/// <summary>
/// 聚合异常过滤器（FastEndpoints post-processor），同时映射 rag 与 file-system 两套领域异常。
/// 使用内核共享的 <see cref="ErrorResponse"/> 信封类型（替代之前的私有 ExceptionEnvelope record）。
/// </summary>