package wire

import (
	"fmt"
	"time"

	"with_you/internal/cache"
	"with_you/internal/config"
	"with_you/internal/database"
	"with_you/internal/pkg/crypto"
	"with_you/internal/pkg/email"
	"with_you/internal/pkg/hook"
	"with_you/internal/pkg/jpush"
	"with_you/internal/pkg/openai"
	"with_you/internal/pkg/redis"
	"with_you/internal/pkg/s3"
	"with_you/internal/pkg/tencent"
	"with_you/internal/pkg/ws"
	"with_you/internal/repository"
	"with_you/internal/service"

	"github.com/google/wire"
	redisPkg "github.com/redis/go-redis/v9"
	"go.uber.org/zap"
	"gorm.io/gorm"
)

// InfrastructureSet 基础设施 Provider Set
var InfrastructureSet = wire.NewSet(
	// 配置
	ProvideConfig,

	// 日志
	ProvideLogger,

	// 数据库
	ProvideDB,

	// 事务管理器
	ProvideTransactionManager,

	// Redis 和缓存
	ProvideRedisClient,
	ProvideCache,

	// 钩子系统
	ProvideHookManager,
	ProvideBuiltinHooks,
	ProvideModerationHooks,

	// WebSocket MessagePublisher
	ProvideWSMessagePublisher,

	// Seq 预分配管理器
	ProvideSeqBufferManager,

	// 推送 Worker
	ProvidePushWorker,

	// 外部服务客户端
	ProvideOpenAIClient,
	ProvideTencentClient,
	ProvideEmailClient,
	ProvideS3Client,
	ProvideJPushClient,

	// 消息加密器
	ProvideMessageEncryptor,
)

// ProvideConfig 加载配置
func ProvideConfig() (*config.Config, error) {
	return config.Load("configs/config.yaml")
}

// ProvideDB 提供数据库连接
func ProvideDB(cfg *config.Config) (*gorm.DB, error) {
	return database.NewDB(&cfg.Database)
}

// ProvideRedisClient 提供 Redis 客户端
func ProvideRedisClient(cfg *config.Config) *redis.Client {
	client, err := redis.New(&cfg.Redis)
	if err != nil {
		zap.L().Warn("Failed to connect to Redis, falling back to memory cache",
			zap.Error(err),
		)
		return nil
	}
	return client
}

// ProvideCache 提供缓存实例
func ProvideCache(cfg *config.Config, redisClient *redis.Client) cache.Cache {
	cache.Configure(cache.Settings{
		Enabled:         cfg.Cache.Enabled,
		KeyPrefix:       cfg.Cache.KeyPrefix,
		DefaultTTL:      time.Duration(cfg.Cache.DefaultTTL) * time.Second,
		NullTTL:         time.Duration(cfg.Cache.NullTTL) * time.Second,
		JitterRatio:     cfg.Cache.JitterRatio,
		PostListTTL:     time.Duration(cfg.Cache.Modules.PostList) * time.Second,
		ConversationTTL: time.Duration(cfg.Cache.Modules.Conversation) * time.Second,
		UnreadCountTTL:  time.Duration(cfg.Cache.Modules.UnreadCount) * time.Second,
		GroupMembersTTL: time.Duration(cfg.Cache.Modules.GroupMembers) * time.Second,
		DisableFlushDB:  cfg.Cache.DisableFlushDB,
	})

	if cfg.Cache.Local.Enabled {
		layeredCache := cache.NewLayeredCache(redisClient, &cache.LayeredCacheOptions{
			LocalSize:       cfg.Cache.Local.Size,
			LocalBuckets:    cfg.Cache.Local.Buckets,
			LocalDefaultTTL: time.Duration(cfg.Cache.Local.DefaultTTL) * time.Second,
			KeyPrefix:       cfg.Cache.KeyPrefix,
			Enabled:         cfg.Cache.Enabled,
		})
		zap.L().Info("Initialized layered cache (local LRU + Redis)")
		return layeredCache
	}

	if redisClient == nil {
		zap.L().Warn("Redis client is nil, cache will not be available")
		return nil
	}

	cacheInstance := cache.NewRedisCache(redisClient)
	zap.L().Info("Initialized Redis cache via dependency injection")
	return cacheInstance
}

// ProvideHookManager 提供钩子管理器
func ProvideHookManager() *hook.Manager {
	return hook.NewManager(&hook.ManagerOptions{
		MaxConcurrentAsync: 100,
		Enabled:            true,
	})
}

// ProvideBuiltinHooks 注册内置钩子
func ProvideBuiltinHooks(manager *hook.Manager) *hook.BuiltinHooks {
	builtin := hook.NewBuiltinHooks(manager)
	builtin.RegisterAll()
	zap.L().Info("Registered builtin hooks")
	return builtin
}

// ProvideModerationHooks 注册审核钩子
func ProvideModerationHooks(
	manager *hook.Manager,
	postAIService service.PostAIService,
	postRepo repository.PostRepository,
	commentRepo repository.CommentRepository,
	userRepo repository.UserRepository,
	sensitiveService service.SensitiveService,
	cfg *config.Config,
) *hook.ModerationHooks {
	strictMode := cfg.OpenAI.StrictModeration

	moderationHooks := hook.NewModerationHooks(
		postAIService,
		sensitiveService,
		postRepo,
		commentRepo,
		userRepo,
		strictMode,
		"***",
	)
	moderationHooks.RegisterAll(manager)
	zap.L().Info("Registered moderation hooks",
		zap.Bool("strict_mode", strictMode),
	)
	return moderationHooks
}

// ProvideWSMessagePublisher 提供 WebSocket 消息发布器
// standalone 模式返回 *Hub，cluster 模式返回 *Bus（组合 Hub + Redis Pub/Sub）
func ProvideWSMessagePublisher(cfg *config.Config, redisClient *redis.Client) ws.MessagePublisher {
	hub := ws.NewHub()

	if cfg.WebSocket.Mode == "cluster" && redisClient != nil {
		bus := ws.NewBus(hub, redisClient.GetClient(), &ws.WSClusterConfig{
			InstanceID:        cfg.WebSocket.Cluster.InstanceID,
			MsgChannel:        cfg.WebSocket.Cluster.MsgChannel,
			OnlineTTL:         cfg.WebSocket.Cluster.OnlineTTL,
			HeartbeatInterval: cfg.WebSocket.Cluster.HeartbeatInterval,
		})
		if err := bus.Start(); err != nil {
			zap.L().Error("Failed to start WebSocket Bus, falling back to standalone mode",
				zap.Error(err),
			)
			return hub
		}
		zap.L().Info("WebSocket running in cluster mode",
			zap.String("instance_id", bus.InstanceID()),
		)
		return bus
	}

	zap.L().Info("WebSocket running in standalone mode")
	return hub
}

// ProvideOpenAIClient 提供 OpenAI 客户端
func ProvideOpenAIClient(cfg *config.Config) openai.Client {
	return openai.NewClient(openai.ConfigFromAppConfig(&cfg.OpenAI))
}

// ProvideTencentClient 提供腾讯云TMS客户端
func ProvideTencentClient(cfg *config.Config) tencent.Client {
	return tencent.NewClient(tencent.Config{
		Enabled:   cfg.TencentTMS.Enabled,
		SecretID:  cfg.TencentTMS.SecretID,
		SecretKey: cfg.TencentTMS.SecretKey,
		Region:    cfg.TencentTMS.Region,
		BizType:   cfg.TencentTMS.BizType,
		Timeout:   cfg.TencentTMS.Timeout,
	})
}

// ProvideEmailClient 提供邮件客户端
func ProvideEmailClient(cfg *config.Config) email.Client {
	return email.NewClient(email.ConfigFromAppConfig(&cfg.Email))
}

// ProvideS3Client 提供 S3 客户端
func ProvideS3Client(cfg *config.Config) (*s3.Client, error) {
	return s3.New(&cfg.S3)
}

// ProvideJPushClient 提供极光推送客户端
func ProvideJPushClient(cfg *config.Config, logger *zap.Logger) *jpush.Client {
	if !cfg.JPush.Enabled {
		logger.Info("JPush is disabled")
		return nil
	}
	if cfg.JPush.AppKey == "" || cfg.JPush.MasterSecret == "" {
		logger.Warn("JPush is enabled but app_key or master_secret is not configured")
		return nil
	}
	client := jpush.NewClient(cfg.JPush.AppKey, cfg.JPush.MasterSecret, cfg.JPush.Production, logger)
	logger.Info("JPush client initialized",
		zap.Bool("production", cfg.JPush.Production),
	)
	return client
}

// ProvideTransactionManager 提供事务管理器
func ProvideTransactionManager(db *gorm.DB) repository.TransactionManager {
	return repository.NewTransactionManager(db)
}

// ProvideMessageEncryptor 提供消息加密器
// 加密启用时密钥必须是 32 字节（AES-256），否则视为致命配置错误，启动期 fail-fast。
func ProvideMessageEncryptor(cfg *config.Config) error {
	if !cfg.Encryption.Enabled {
		zap.L().Info("Message encryption is disabled")
		return nil
	}

	if len(cfg.Encryption.Key) != 32 {
		// 致命安全配置：不允许降级为「加密已启用但实际不加密」
		return fmt.Errorf("encryption is enabled but key must be 32 bytes for AES-256, got %d", len(cfg.Encryption.Key))
	}

	if err := crypto.InitMessageEncryptor(cfg.Encryption.Key, cfg.Encryption.KeyVersion); err != nil {
		return fmt.Errorf("failed to initialize message encryptor: %w", err)
	}

	zap.L().Info("Message encryption initialized successfully",
		zap.Int("key_version", cfg.Encryption.KeyVersion),
	)
	return nil
}

// ProvideLogger 提供 Zap Logger
func ProvideLogger() *zap.Logger {
	logger, err := zap.NewProduction()
	if err != nil {
		panic("Failed to create logger: " + err.Error())
	}
	// 设置为全局 logger，以便在其他地方使用 zap.L()
	zap.ReplaceGlobals(logger)
	return logger
}

// ProvideSeqBufferManager 提供 Seq 预分配管理器
func ProvideSeqBufferManager(cfg *config.Config, redisClient *redis.Client, cacheBackend cache.Cache) *cache.SeqBufferManager {
	seqCfg := cache.SeqBufferConfig{
		Enabled:           cfg.SeqBuffer.Enabled,
		PrivateBufferSize: cfg.SeqBuffer.PrivateBufferSize,
		GroupBufferSize:   cfg.SeqBuffer.GroupBufferSize,
		LockTimeoutMs:     cfg.SeqBuffer.LockTimeoutMs,
		MaxRetries:        cfg.SeqBuffer.MaxRetries,
	}
	if !seqCfg.Enabled {
		return cache.NewSeqBufferManager(nil, seqCfg, nil, nil)
	}
	return cache.NewSeqBufferManagerFromRedisPkg(redisClient, seqCfg, nil, nil)
}

// ProvidePushWorker 提供推送 Worker（Redis Stream 异步推送）
func ProvidePushWorker(
	cfg *config.Config,
	redisClient *redis.Client,
	publisher ws.MessagePublisher,
	pushSvc service.PushService,
	msgRepo repository.MessageRepository,
	userRepo repository.UserRepository,
) *service.PushWorker {
	pushCfg := service.PushWorkerConfig{
		Enabled:       cfg.PushWorker.Enabled,
		Stream:        cfg.PushWorker.Stream,
		Group:         cfg.PushWorker.Group,
		BatchSize:     cfg.PushWorker.BatchSize,
		PollTimeoutMs: cfg.PushWorker.PollTimeoutMs,
		MaxRetries:    cfg.PushWorker.MaxRetries,
		MaxStreamLen:  cfg.PushWorker.MaxStreamLen,
		IdleTimeoutMs: cfg.PushWorker.IdleTimeoutMs,
	}
	if !pushCfg.Enabled {
		return service.NewPushWorker(nil, nil, nil, nil, nil, pushCfg)
	}
	var rdb *redisPkg.Client
	if redisClient != nil {
		rdb = redisClient.GetClient()
	}
	return service.NewPushWorker(rdb, publisher, pushSvc, msgRepo, userRepo, pushCfg)
}