package main

import (
	"flag"
	"fmt"
	"os"
	"os/signal"
	"strconv"
	"syscall"

	"dubbo.apache.org/dubbo-go/v3/client"
	_ "dubbo.apache.org/dubbo-go/v3/imports"
	"dubbo.apache.org/dubbo-go/v3/protocol"
	"dubbo.apache.org/dubbo-go/v3/server"

	"github.com/topfans/backend/pkg/database"
	"github.com/topfans/backend/pkg/health"
	"github.com/topfans/backend/pkg/logger"
	"github.com/topfans/backend/pkg/models"
	pb "github.com/topfans/backend/pkg/proto/social"
	pbUser "github.com/topfans/backend/pkg/proto/user"
	socialClient "github.com/topfans/backend/services/socialService/client"
	"github.com/topfans/backend/services/socialService/provider"
	"github.com/topfans/backend/services/socialService/repository"
	"github.com/topfans/backend/services/socialService/service"
)

var (
	port            = flag.Int("port", getEnvInt("PORT", 20002), "Dubbo service port")
	dbHost          = flag.String("db-host", getEnv("DB_HOST", "localhost"), "Database host")
	dbPort          = flag.Int("db-port", getEnvInt("DB_PORT", 5432), "Database port")
	dbUser          = flag.String("db-user", getEnv("DB_USER", "postgres"), "Database user")
	dbPassword      = flag.String("db-password", getEnv("DB_PASSWORD", ""), "Database password")
	dbName          = flag.String("db-name", getEnv("DB_NAME", "top-fans"), "Database name")
	userServiceURL  = flag.String("user-service-url", getEnv("USER_SERVICE_URL", "tri://localhost:20000"), "User service URL")
	assetServiceURL = flag.String("asset-service-url", getEnv("ASSET_SERVICE_URL", "tri://localhost:20003"), "Asset service URL")
	healthHandler   *health.Handler
)

func getEnv(key, fallback string) string {
	if v := os.Getenv(key); v != "" {
		return v
	}
	return fallback
}

func getEnvInt(key string, fallback int) int {
	if v := os.Getenv(key); v != "" {
		if n, err := strconv.Atoi(v); err == nil {
			return n
		}
	}
	return fallback
}

func main() {
	flag.Parse()

	// 初始化日志（必须在最前面）
	env := os.Getenv("ENV")
	if env == "" {
		env = "development"
	}

	if err := logger.Init(logger.Config{
		ServiceName: "social-service",
		Environment: env,
		LogLevel:    os.Getenv("LOG_LEVEL"),
	}); err != nil {
		panic(fmt.Sprintf("Failed to initialize logger: %v", err))
	}
	defer logger.Sync()

	logger.Sugar.Info("Starting Social Service...")

	// 初始化数据库
	if err := initDatabase(); err != nil {
		logger.Sugar.Fatalf("Failed to initialize database: %v", err)
	}

	// 自动迁移数据库表
	if err := autoMigrate(); err != nil {
		logger.Sugar.Fatalf("Failed to migrate database: %v", err)
	}

	// 初始化 Dubbo-go 服务器
	if err := initDubboService(); err != nil {
		logger.Sugar.Fatalf("Failed to initialize Dubbo service: %v", err)
	}

	// 等待信号（优雅关闭）
	logger.Sugar.Info("Social service started successfully. Press Ctrl+C to exit.")
	gracefulShutdown()
}

// initDatabase 初始化数据库连接
func initDatabase() error {
	config := database.Config{
		Host:     *dbHost,
		Port:     *dbPort,
		User:     *dbUser,
		Password: *dbPassword,
		DBName:   *dbName,
		SSLMode:  "disable",
		TimeZone: "Asia/Shanghai",
	}

	return database.Init(config)
}

// autoMigrate 自动迁移数据库表
func autoMigrate() error {
	db := database.GetDB()
	if db == nil {
		return fmt.Errorf("database is not initialized")
	}

	// 迁移好友相关表
	tables := []interface{}{
		&models.FriendRequest{},
		&models.Friendship{},
	}

	for _, table := range tables {
		if err := db.AutoMigrate(table); err != nil {
			return fmt.Errorf("failed to migrate table: %w", err)
		}
	}

	logger.Sugar.Info("Database migration completed successfully")
	return nil
}

// gracefulShutdown 优雅关闭
func gracefulShutdown() {
	quit := make(chan os.Signal, 1)
	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
	<-quit

	logger.Sugar.Info("Shutting down server...")

	// 关闭健康检查服务器
	if healthHandler != nil {
		healthHandler.Stop()
	}

	// 关闭数据库连接
	if err := database.Close(); err != nil {
		logger.Sugar.Errorf("Error closing database: %v", err)
	}

	logger.Sugar.Info("Server exited")
}

// initDubboService 初始化Dubbo-go服务
func initDubboService() error {
	// 启动健康检查 HTTP 服务器
	healthPort := *port + 1000 // e.g., 20002 -> 21002
	healthHandler = health.NewHandler("social-service", healthPort)
	healthHandler.Start()

	db := database.GetDB()
	if db == nil {
		return fmt.Errorf("database is not initialized")
	}

	// 创建Repository实例
	socialRepo := repository.NewSocialRepository()

	// 创建UserService RPC客户端
	userServiceClient, err := createUserServiceClient()
	if err != nil {
		return fmt.Errorf("failed to create user service client: %w", err)
	}

	// 创建AssetService RPC客户端
	assetClient, err := createAssetServiceClient(*assetServiceURL)
	if err != nil {
		return fmt.Errorf("failed to create asset service client: %w", err)
	}

	// 创建Service实例
	friendService := service.NewFriendService(socialRepo, userServiceClient, db)
	assetLikeService := service.NewAssetLikeService(assetClient)

	// 创建Provider实例
	socialProvider := provider.NewSocialProvider(friendService, assetLikeService)

	// 创建 Dubbo Server
	srv, err := server.NewServer(
		server.WithServerProtocol(
			protocol.WithPort(*port),
			protocol.WithTriple(),
		),
	)
	if err != nil {
		return fmt.Errorf("failed to create Dubbo server: %w", err)
	}

	// 使用 Triple 协议生成的 RegisterHandler 函数注册服务
	if err := pb.RegisterSocialServiceHandler(srv, socialProvider); err != nil {
		return fmt.Errorf("failed to register SocialService handler: %w", err)
	}

	logger.Sugar.Info("Dubbo-go social provider registered successfully",
		"service", "topfans.social.SocialService",
		"port", *port,
	)

	// 在后台启动 Dubbo 服务器
	go func() {
		if err := srv.Serve(); err != nil {
			logger.Sugar.Fatalf("Failed to serve Dubbo: %v", err)
		}
	}()

	return nil
}

// createUserServiceClient 创建UserService RPC客户端
func createUserServiceClient() (service.UserServiceClient, error) {
	// 创建 Dubbo 客户端（直连模式）
	// URL 格式：tri://host:port
	cli, err := client.NewClient(
		client.WithClientURL(*userServiceURL),
	)
	if err != nil {
		return nil, fmt.Errorf("failed to create Dubbo client: %w", err)
	}

	// 创建 UserSocialService 客户端
	// NewUserSocialService 会自动处理接口名称和连接
	svc, err := pbUser.NewUserSocialService(cli)
	if err != nil {
		return nil, fmt.Errorf("failed to create UserSocialService: %w", err)
	}

	// 创建我们的 RPC 客户端封装
	userServiceClient := service.NewUserServiceClient(svc)

	logger.Sugar.Info("User service client created successfully", "url", *userServiceURL)

	return userServiceClient, nil
}

// createAssetServiceClient 创建AssetService RPC客户端
func createAssetServiceClient(serviceURL string) (*socialClient.AssetClient, error) {
	assetClient, err := socialClient.NewAssetClient(serviceURL, logger.Logger)
	if err != nil {
		return nil, fmt.Errorf("failed to create asset client: %w", err)
	}

	logger.Sugar.Info("Asset service client created successfully", "url", serviceURL)

	return assetClient, nil
}