mod config;
mod db;
mod handlers;
mod middleware;
mod outbox;
mod state;

/// OpenAPI 规范定义 — 通过 utoipa derive 合并各模块 schema。
#[derive(OpenApi)]
#[openapi(info(
    title = "ERP Platform API",
    version = "0.1.0",
    description = "ERP 平台底座 REST API 文档"
))]
struct ApiDoc;

/// Auth 模块的 OpenAPI 路径收集
#[derive(OpenApi)]
#[openapi(
    paths(
        erp_auth::handler::auth_handler::login,
        erp_auth::handler::auth_handler::refresh,
        erp_auth::handler::auth_handler::logout,
        erp_auth::handler::auth_handler::change_password,
        erp_auth::handler::user_handler::list_users,
        erp_auth::handler::user_handler::create_user,
        erp_auth::handler::user_handler::get_user,
        erp_auth::handler::user_handler::update_user,
        erp_auth::handler::user_handler::delete_user,
        erp_auth::handler::user_handler::assign_roles,
        erp_auth::handler::role_handler::list_roles,
        erp_auth::handler::role_handler::create_role,
        erp_auth::handler::role_handler::get_role,
        erp_auth::handler::role_handler::update_role,
        erp_auth::handler::role_handler::delete_role,
        erp_auth::handler::role_handler::assign_permissions,
        erp_auth::handler::role_handler::get_role_permissions,
        erp_auth::handler::role_handler::list_permissions,
    ),
    components(
        schemas(
            erp_auth::dto::LoginReq,
            erp_auth::dto::LoginResp,
            erp_auth::dto::RefreshReq,
            erp_auth::dto::UserResp,
            erp_auth::dto::CreateUserReq,
            erp_auth::dto::UpdateUserReq,
            erp_auth::dto::RoleResp,
            erp_auth::dto::CreateRoleReq,
            erp_auth::dto::UpdateRoleReq,
            erp_auth::dto::PermissionResp,
            erp_auth::dto::AssignPermissionsReq,
            erp_auth::dto::ChangePasswordReq,
        )
    )
)]
struct AuthApiDoc;

/// Config 模块的 OpenAPI 路径收集
#[derive(OpenApi)]
#[openapi(
    paths(
        erp_config::handler::dictionary_handler::list_dictionaries,
        erp_config::handler::dictionary_handler::create_dictionary,
        erp_config::handler::dictionary_handler::update_dictionary,
        erp_config::handler::dictionary_handler::delete_dictionary,
        erp_config::handler::dictionary_handler::list_items_by_code,
        erp_config::handler::dictionary_handler::create_item,
        erp_config::handler::dictionary_handler::update_item,
        erp_config::handler::menu_handler::get_menus,
        erp_config::handler::menu_handler::create_menu,
        erp_config::handler::menu_handler::update_menu,
        erp_config::handler::menu_handler::delete_menu,
        erp_config::handler::numbering_handler::list_numbering_rules,
        erp_config::handler::numbering_handler::create_numbering_rule,
        erp_config::handler::numbering_handler::update_numbering_rule,
        erp_config::handler::numbering_handler::generate_number,
        erp_config::handler::numbering_handler::delete_numbering_rule,
        erp_config::handler::theme_handler::get_theme,
        erp_config::handler::theme_handler::update_theme,
        erp_config::handler::language_handler::list_languages,
        erp_config::handler::language_handler::update_language,
        erp_config::handler::setting_handler::get_setting,
        erp_config::handler::setting_handler::update_setting,
        erp_config::handler::setting_handler::delete_setting,
    ),
    components(
        schemas(
            erp_config::dto::DictionaryResp,
            erp_config::dto::CreateDictionaryReq,
            erp_config::dto::UpdateDictionaryReq,
            erp_config::dto::DictionaryItemResp,
            erp_config::dto::CreateDictionaryItemReq,
            erp_config::dto::UpdateDictionaryItemReq,
            erp_config::dto::MenuResp,
            erp_config::dto::CreateMenuReq,
            erp_config::dto::UpdateMenuReq,
            erp_config::dto::NumberingRuleResp,
            erp_config::dto::CreateNumberingRuleReq,
            erp_config::dto::UpdateNumberingRuleReq,
            erp_config::dto::ThemeResp,
        )
    )
)]
struct ConfigApiDoc;

/// Workflow 模块的 OpenAPI 路径收集
#[derive(OpenApi)]
#[openapi(
    paths(
        erp_workflow::handler::definition_handler::list_definitions,
        erp_workflow::handler::definition_handler::create_definition,
        erp_workflow::handler::definition_handler::get_definition,
        erp_workflow::handler::definition_handler::update_definition,
        erp_workflow::handler::definition_handler::publish_definition,
        erp_workflow::handler::instance_handler::start_instance,
        erp_workflow::handler::instance_handler::list_instances,
        erp_workflow::handler::instance_handler::get_instance,
        erp_workflow::handler::instance_handler::suspend_instance,
        erp_workflow::handler::instance_handler::terminate_instance,
        erp_workflow::handler::instance_handler::resume_instance,
        erp_workflow::handler::task_handler::list_pending_tasks,
        erp_workflow::handler::task_handler::list_completed_tasks,
        erp_workflow::handler::task_handler::complete_task,
        erp_workflow::handler::task_handler::delegate_task,
    ),
    components(
        schemas(
            erp_workflow::dto::ProcessDefinitionResp,
            erp_workflow::dto::CreateProcessDefinitionReq,
            erp_workflow::dto::UpdateProcessDefinitionReq,
            erp_workflow::dto::ProcessInstanceResp,
            erp_workflow::dto::StartInstanceReq,
            erp_workflow::dto::TaskResp,
            erp_workflow::dto::CompleteTaskReq,
            erp_workflow::dto::DelegateTaskReq,
        )
    )
)]
struct WorkflowApiDoc;

/// Message 模块的 OpenAPI 路径收集
#[derive(OpenApi)]
#[openapi(
    paths(
        erp_message::handler::message_handler::list_messages,
        erp_message::handler::message_handler::unread_count,
        erp_message::handler::message_handler::send_message,
        erp_message::handler::message_handler::mark_read,
        erp_message::handler::message_handler::mark_all_read,
        erp_message::handler::message_handler::delete_message,
        erp_message::handler::template_handler::list_templates,
        erp_message::handler::template_handler::create_template,
        erp_message::handler::subscription_handler::update_subscription,
    ),
    components(
        schemas(
            erp_message::dto::MessageResp,
            erp_message::dto::SendMessageReq,
            erp_message::dto::MessageQuery,
            erp_message::dto::UnreadCountResp,
            erp_message::dto::MessageTemplateResp,
            erp_message::dto::CreateTemplateReq,
            erp_message::dto::MessageSubscriptionResp,
            erp_message::dto::UpdateSubscriptionReq,
        )
    )
)]
struct MessageApiDoc;

use axum::Router;
use axum::middleware as axum_middleware;
use config::AppConfig;
use erp_auth::middleware::jwt_auth_middleware_fn;
use state::AppState;
use tracing_subscriber::EnvFilter;
use utoipa::OpenApi;

use erp_core::events::EventBus;
use erp_core::module::{ErpModule, ModuleContext, ModuleRegistry};
use erp_server_migration::MigratorTrait;
use sea_orm::{ConnectionTrait, FromQueryResult};

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    // Load config
    let config = AppConfig::load()?;

    // Initialize tracing
    tracing_subscriber::fmt()
        .with_env_filter(
            EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new(&config.log.level)),
        )
        .json()
        .init();

    tracing::info!(
        version = env!("CARGO_PKG_VERSION"),
        "ERP Server starting..."
    );

    // Connect to database
    let db = db::connect(&config.database).await?;

    // Run migrations
    erp_server_migration::Migrator::up(&db, None).await?;
    tracing::info!("Database migrations applied");

    // Seed default tenant and auth data if not present, and resolve the actual tenant ID
    let default_tenant_id = {
        #[derive(sea_orm::FromQueryResult)]
        struct TenantId {
            id: uuid::Uuid,
        }

        let existing = TenantId::find_by_statement(sea_orm::Statement::from_string(
            sea_orm::DatabaseBackend::Postgres,
            "SELECT id FROM tenant WHERE deleted_at IS NULL LIMIT 1".to_string(),
        ))
        .one(&db)
        .await
        .map_err(|e| anyhow::anyhow!("Failed to query tenants: {}", e))?;

        match existing {
            Some(row) => {
                tracing::info!(tenant_id = %row.id, "Default tenant already exists, skipping seed");
                row.id
            }
            None => {
                let new_tenant_id = uuid::Uuid::now_v7();

                // Insert default tenant using raw SQL (no tenant entity in erp-server)
                db.execute(sea_orm::Statement::from_sql_and_values(
                    sea_orm::DatabaseBackend::Postgres,
                    "INSERT INTO tenant (id, name, code, status, created_at, updated_at) VALUES ($1, $2, $3, $4, NOW(), NOW())",
                    [
                        new_tenant_id.into(),
                        "Default Tenant".into(),
                        "default".into(),
                        "active".into(),
                    ],
                ))
                .await
                .map_err(|e| anyhow::anyhow!("Failed to create default tenant: {}", e))?;

                tracing::info!(tenant_id = %new_tenant_id, "Created default tenant");

                // Seed auth data (permissions, roles, admin user)
                erp_auth::service::seed::seed_tenant_auth(
                    &db,
                    new_tenant_id,
                    &config.auth.super_admin_password,
                )
                .await
                .map_err(|e| anyhow::anyhow!("Failed to seed auth data: {}", e))?;

                tracing::info!(tenant_id = %new_tenant_id, "Default tenant ready with auth seed data");
                new_tenant_id
            }
        }
    };

    // Connect to Redis
    let redis_client = redis::Client::open(&config.redis.url[..])?;
    tracing::info!("Redis client created");

    // Initialize event bus (capacity 1024 events)
    let event_bus = EventBus::new(1024);

    // Initialize auth module
    let auth_module = erp_auth::AuthModule::new();
    tracing::info!(
        module = auth_module.name(),
        version = auth_module.version(),
        "Auth module initialized"
    );

    // Initialize config module
    let config_module = erp_config::ConfigModule::new();
    tracing::info!(
        module = config_module.name(),
        version = config_module.version(),
        "Config module initialized"
    );

    // Initialize workflow module
    let workflow_module = erp_workflow::WorkflowModule::new();
    tracing::info!(
        module = workflow_module.name(),
        version = workflow_module.version(),
        "Workflow module initialized"
    );

    // Initialize message module
    let message_module = erp_message::MessageModule::new();
    tracing::info!(
        module = message_module.name(),
        version = message_module.version(),
        "Message module initialized"
    );

    // Initialize module registry and register modules
    let registry = ModuleRegistry::new()
        .register(auth_module)
        .register(config_module)
        .register(workflow_module)
        .register(message_module);
    tracing::info!(
        module_count = registry.modules().len(),
        "Modules registered"
    );

    // Initialize plugin engine
    let plugin_config = erp_plugin::engine::PluginEngineConfig::default();
    let plugin_engine = erp_plugin::engine::PluginEngine::new(
        db.clone(),
        event_bus.clone(),
        plugin_config,
    )?;
    tracing::info!("Plugin engine initialized");

    // Register plugin module
    let plugin_module = erp_plugin::module::PluginModule;
    let registry = registry.register(plugin_module);

    // Register event handlers
    registry.register_handlers(&event_bus);

    // Startup all modules (按拓扑顺序调用 on_startup)
    let module_ctx = ModuleContext {
        db: db.clone(),
        event_bus: event_bus.clone(),
    };
    registry.startup_all(&module_ctx).await?;
    tracing::info!("All modules started");

    // 恢复运行中的插件（服务器重启后自动重新加载）
    match plugin_engine.recover_plugins(&db).await {
        Ok(recovered) => {
            tracing::info!(count = recovered.len(), "Plugins recovered");
        }
        Err(e) => {
            tracing::error!(error = %e, "Failed to recover plugins");
        }
    }

    // Start message event listener (workflow events → message notifications)
    erp_message::MessageModule::start_event_listener(db.clone(), event_bus.clone());
    tracing::info!("Message event listener started");

    // Start outbox relay (re-publish pending domain events)
    outbox::start_outbox_relay(db.clone(), event_bus.clone());
    tracing::info!("Outbox relay started");

    // Start timeout checker (scan overdue tasks every 60s)
    erp_workflow::WorkflowModule::start_timeout_checker(db.clone());
    tracing::info!("Timeout checker started");

    let host = config.server.host.clone();
    let port = config.server.port;

    // Extract JWT secret for middleware construction
    let jwt_secret = config.jwt.secret.clone();

    // Build shared state
    let state = AppState {
        db,
        config,
        event_bus,
        module_registry: registry,
        redis: redis_client.clone(),
        default_tenant_id,
        plugin_engine,
        plugin_entity_cache: moka::sync::Cache::builder()
            .max_capacity(1000)
            .time_to_idle(std::time::Duration::from_secs(300))
            .build(),
    };

    // --- Build the router ---
    //
    // The router is split into two layers:
    //   1. Public routes: no JWT required (health, login, refresh)
    //   2. Protected routes: JWT required (user CRUD, logout)
    //
    // Both layers share the same AppState. The protected layer wraps routes
    // with the jwt_auth_middleware_fn.

    // Public routes (no authentication, but IP-based rate limiting)
    let public_routes = Router::new()
        .merge(handlers::health::health_check_router())
        .merge(erp_auth::AuthModule::public_routes())
        .route(
            "/docs/openapi.json",
            axum::routing::get(handlers::openapi::openapi_spec),
        )
        .layer(axum::middleware::from_fn_with_state(
            state.clone(),
            middleware::rate_limit::rate_limit_by_ip,
        ))
        .with_state(state.clone());

    // Protected routes (JWT authentication required)
    // User-based rate limiting (100 req/min) applied after JWT auth
    let protected_routes = erp_auth::AuthModule::protected_routes()
        .merge(erp_config::ConfigModule::protected_routes())
        .merge(erp_workflow::WorkflowModule::protected_routes())
        .merge(erp_message::MessageModule::protected_routes())
        .merge(erp_plugin::module::PluginModule::protected_routes())
        .merge(handlers::audit_log::audit_log_router())
        .layer(axum::middleware::from_fn_with_state(
            state.clone(),
            middleware::rate_limit::rate_limit_by_user,
        ))
        .layer(axum_middleware::from_fn(move |req, next| {
            let secret = jwt_secret.clone();
            async move { jwt_auth_middleware_fn(secret, req, next).await }
        }))
        .with_state(state.clone());

    // Merge public + protected into the final application router
    // All API routes are nested under /api/v1
    let cors = build_cors_layer(&state.config.cors.allowed_origins);
    let app = Router::new()
        .nest("/api/v1", public_routes.merge(protected_routes))
        .layer(cors);

    let addr = format!("{}:{}", host, port);
    let listener = tokio::net::TcpListener::bind(&addr).await?;
    tracing::info!(addr = %addr, "Server listening");

    // Graceful shutdown on CTRL+C
    axum::serve(listener, app)
        .with_graceful_shutdown(shutdown_signal())
        .await?;

    // 优雅关闭所有模块（按拓扑逆序）
    state.module_registry.shutdown_all().await?;
    tracing::info!("Server shutdown complete");
    Ok(())
}

/// Build a CORS layer from the comma-separated allowed origins config.
///
/// If the config is "*", allows all origins (development mode).
/// Otherwise, parses each origin as a URL and restricts to those origins only.
fn build_cors_layer(allowed_origins: &str) -> tower_http::cors::CorsLayer {
    use axum::http::HeaderValue;
    use tower_http::cors::AllowOrigin;

    let origins = allowed_origins
        .split(',')
        .map(|s| s.trim())
        .filter(|s| !s.is_empty())
        .collect::<Vec<_>>();

    if origins.len() == 1 && origins[0] == "*" {
        tracing::warn!(
            "⚠️  CORS 允许所有来源 — 仅限开发环境使用！\
             生产环境请通过 ERP__CORS__ALLOWED_ORIGINS 设置具体的来源域名"
        );
        return tower_http::cors::CorsLayer::permissive();
    }

    let allowed: Vec<HeaderValue> = origins
        .iter()
        .filter_map(|o| o.parse::<HeaderValue>().ok())
        .collect();

    tracing::info!(origins = ?origins, "CORS: restricting to allowed origins");

    tower_http::cors::CorsLayer::new()
        .allow_origin(AllowOrigin::list(allowed))
        .allow_methods([
            axum::http::Method::GET,
            axum::http::Method::POST,
            axum::http::Method::PUT,
            axum::http::Method::DELETE,
            axum::http::Method::PATCH,
        ])
        .allow_headers([
            axum::http::header::AUTHORIZATION,
            axum::http::header::CONTENT_TYPE,
        ])
        .allow_credentials(true)
}

async fn shutdown_signal() {
    let ctrl_c = async {
        tokio::signal::ctrl_c()
            .await
            .expect("failed to install CTRL+C handler");
    };

    #[cfg(unix)]
    let terminate = async {
        tokio::signal::unix::signal(tokio::signal::unix::SignalKind::terminate())
            .expect("failed to install signal handler")
            .recv()
            .await;
    };

    #[cfg(not(unix))]
    let terminate = std::future::pending::<()>();

    tokio::select! {
        _ = ctrl_c => {
            tracing::info!("Received CTRL+C, shutting down gracefully...");
        },
        _ = terminate => {
            tracing::info!("Received SIGTERM, shutting down gracefully...");
        },
    }
}