package interfaces

import (
	"context"
	"errors"

	"tyapi-server/internal/application/user/dto/commands"
	"tyapi-server/internal/domains/user/entities"
)

// 常见错误定义
var (
	ErrCacheMiss = errors.New("cache miss")
)

// Service 通用服务接口
type Service interface {
	// 服务名称
	Name() string
	// 服务初始化
	Initialize(ctx context.Context) error
	// 服务健康检查
	HealthCheck(ctx context.Context) error
	// 服务关闭
	Shutdown(ctx context.Context) error
}

// UserService 用户服务接口
type UserService interface {
	Service

	// 用户注册
	Register(ctx context.Context, req *commands.RegisterUserCommand) (*entities.User, error)
	// 密码登录
	LoginWithPassword(ctx context.Context, req *commands.LoginWithPasswordCommand) (*entities.User, error)
	// 短信验证码登录
	LoginWithSMS(ctx context.Context, req *commands.LoginWithSMSCommand) (*entities.User, error)
	// 修改密码
	ChangePassword(ctx context.Context, userID string, req *commands.ChangePasswordCommand) error
	// 根据ID获取用户
	GetByID(ctx context.Context, id string) (*entities.User, error)
}

// DomainService 领域服务接口，支持泛型
type DomainService[T Entity] interface {
	Service

	// 基础业务操作
	Create(ctx context.Context, dto interface{}) (*T, error)
	GetByID(ctx context.Context, id string) (*T, error)
	Update(ctx context.Context, id string, dto interface{}) (*T, error)
	Delete(ctx context.Context, id string) error

	// 列表和查询
	List(ctx context.Context, options ListOptions) ([]*T, error)
	Search(ctx context.Context, query string, options ListOptions) ([]*T, error)
	Count(ctx context.Context, options CountOptions) (int64, error)

	// 业务规则验证
	Validate(ctx context.Context, entity *T) error
	ValidateCreate(ctx context.Context, dto interface{}) error
	ValidateUpdate(ctx context.Context, id string, dto interface{}) error
}

// EventService 事件服务接口
type EventService interface {
	Service

	// 事件发布
	Publish(ctx context.Context, event Event) error
	PublishBatch(ctx context.Context, events []Event) error

	// 事件订阅
	Subscribe(eventType string, handler EventHandler) error
	Unsubscribe(eventType string, handler EventHandler) error

	// 异步处理
	PublishAsync(ctx context.Context, event Event) error
}

// CacheService 缓存服务接口
type CacheService interface {
	Service

	// 基础缓存操作
	Get(ctx context.Context, key string, dest interface{}) error
	Set(ctx context.Context, key string, value interface{}, ttl ...interface{}) error
	Delete(ctx context.Context, keys ...string) error
	Exists(ctx context.Context, key string) (bool, error)

	// 批量操作
	GetMultiple(ctx context.Context, keys []string) (map[string]interface{}, error)
	SetMultiple(ctx context.Context, data map[string]interface{}, ttl ...interface{}) error

	// 模式操作
	DeletePattern(ctx context.Context, pattern string) error
	Keys(ctx context.Context, pattern string) ([]string, error)

	// 缓存统计
	Stats(ctx context.Context) (CacheStats, error)
}

// CacheStats 缓存统计信息
type CacheStats struct {
	Hits        int64 `json:"hits"`
	Misses      int64 `json:"misses"`
	Keys        int64 `json:"keys"`
	Memory      int64 `json:"memory"`
	Connections int64 `json:"connections"`
}

// TransactionService 事务服务接口
type TransactionService interface {
	Service

	// 事务操作
	Begin(ctx context.Context) (Transaction, error)
	RunInTransaction(ctx context.Context, fn func(Transaction) error) error
}

// Transaction 事务接口
type Transaction interface {
	Commit() error
	Rollback() error
	GetDB() interface{}
}