package service

import (
	"context"
	"time"

	"with_you/internal/repository"

	"go.uber.org/zap"
)

// LogCleanupConfig 日志清理配置
type LogCleanupConfig struct {
	Enabled       bool
	OperationLog  int // 保留天数
	LoginLog      int
	DataChangeLog int
	CleanupTime   string // 清理时间，如 "02:00"
}

// LogCleanupService 日志清理服务接口
type LogCleanupService interface {
	Start()
	Stop()
	CleanupOldLogs(ctx context.Context) error
	CleanupOperationLogs(ctx context.Context, beforeDate string) error
	CleanupLoginLogs(ctx context.Context, beforeDate string) error
	CleanupDataChangeLogs(ctx context.Context, beforeDate string) error
}

// logCleanupServiceImpl 日志清理服务实现
type logCleanupServiceImpl struct {
	operationRepo  repository.OperationLogRepository
	loginRepo      repository.LoginLogRepository
	dataChangeRepo repository.DataChangeLogRepository
	cfg            *LogCleanupConfig
	logger         *zap.Logger
	ctx            context.Context
	cancel         context.CancelFunc
}

// NewLogCleanupService 创建日志清理服务
func NewLogCleanupService(
	operationRepo repository.OperationLogRepository,
	loginRepo repository.LoginLogRepository,
	dataChangeRepo repository.DataChangeLogRepository,
	cfg *LogCleanupConfig,
	logger *zap.Logger,
) LogCleanupService {
	return &logCleanupServiceImpl{
		operationRepo:  operationRepo,
		loginRepo:      loginRepo,
		dataChangeRepo: dataChangeRepo,
		cfg:            cfg,
		logger:         logger,
	}
}

// Start 启动日志清理服务
func (s *logCleanupServiceImpl) Start() {
	if !s.cfg.Enabled {
		s.logger.Info("log cleanup service disabled")
		return
	}

	s.ctx, s.cancel = context.WithCancel(context.Background())

	go s.scheduleCleanup()

	s.logger.Info("log cleanup service started",
		zap.Int("operation_log_days", s.cfg.OperationLog),
		zap.Int("login_log_days", s.cfg.LoginLog),
		zap.Int("data_change_log_days", s.cfg.DataChangeLog),
	)
}

// Stop 停止日志清理服务
func (s *logCleanupServiceImpl) Stop() {
	if s.cancel != nil {
		s.cancel()
		s.logger.Info("log cleanup service stopped")
	}
}

// scheduleCleanup 定时调度清理任务
func (s *logCleanupServiceImpl) scheduleCleanup() {
	for {
		select {
		case <-s.ctx.Done():
			return
		default:
			now := time.Now()
			nextCleanup := s.getNextCleanupTime(now)
			duration := nextCleanup.Sub(now)

			s.logger.Info("next log cleanup scheduled",
				zap.Time("time", nextCleanup),
				zap.Duration("in", duration),
			)

			timer := time.NewTimer(duration)
			select {
			case <-s.ctx.Done():
				timer.Stop()
				return
			case <-timer.C:
				if err := s.CleanupOldLogs(s.ctx); err != nil {
					s.logger.Error("failed to cleanup old logs", zap.Error(err))
				}
			}
		}
	}
}

// getNextCleanupTime 计算下次清理时间
func (s *logCleanupServiceImpl) getNextCleanupTime(now time.Time) time.Time {
	cleanupTime, err := time.Parse("15:04", s.cfg.CleanupTime)
	if err != nil {
		cleanupTime = time.Date(now.Year(), now.Month(), now.Day(), 2, 0, 0, 0, now.Location())
	}

	nextCleanup := time.Date(now.Year(), now.Month(), now.Day(), cleanupTime.Hour(), cleanupTime.Minute(), 0, 0, now.Location())

	if nextCleanup.Before(now) {
		nextCleanup = nextCleanup.Add(24 * time.Hour)
	}

	return nextCleanup
}

// CleanupOldLogs 清理旧日志
func (s *logCleanupServiceImpl) CleanupOldLogs(ctx context.Context) error {
	s.logger.Info("starting log cleanup")

	// 清理操作日志
	if err := s.CleanupOperationLogs(ctx, s.getBeforeDate(s.cfg.OperationLog)); err != nil {
		s.logger.Error("failed to cleanup operation logs", zap.Error(err))
	}

	// 清理登录日志
	if err := s.CleanupLoginLogs(ctx, s.getBeforeDate(s.cfg.LoginLog)); err != nil {
		s.logger.Error("failed to cleanup login logs", zap.Error(err))
	}

	// 清理数据变更日志
	if err := s.CleanupDataChangeLogs(ctx, s.getBeforeDate(s.cfg.DataChangeLog)); err != nil {
		s.logger.Error("failed to cleanup data change logs", zap.Error(err))
	}

	s.logger.Info("log cleanup completed")
	return nil
}

// CleanupOperationLogs 清理操作日志
func (s *logCleanupServiceImpl) CleanupOperationLogs(ctx context.Context, beforeDate string) error {
	result := s.operationRepo.DeleteOldLogs(ctx, beforeDate)
	s.logger.Info("cleanup operation logs", zap.String("before_date", beforeDate))
	return result
}

// CleanupLoginLogs 清理登录日志
func (s *logCleanupServiceImpl) CleanupLoginLogs(ctx context.Context, beforeDate string) error {
	result := s.loginRepo.DeleteOldLogs(ctx, beforeDate)
	s.logger.Info("cleanup login logs", zap.String("before_date", beforeDate))
	return result
}

// CleanupDataChangeLogs 清理数据变更日志
func (s *logCleanupServiceImpl) CleanupDataChangeLogs(ctx context.Context, beforeDate string) error {
	result := s.dataChangeRepo.DeleteOldLogs(ctx, beforeDate)
	s.logger.Info("cleanup data change logs", zap.String("before_date", beforeDate))
	return result
}

// getBeforeDate 计算截止日期
func (s *logCleanupServiceImpl) getBeforeDate(days int) string {
	return time.Now().AddDate(0, 0, -days).Format("2006-01-02")
}

// LogService 日志服务组合
type LogService struct {
	OperationLog  OperationLogService
	LoginLog      LoginLogService
	DataChangeLog DataChangeLogService
}

// NewLogService 创建日志服务组合
func NewLogService(
	operationLogService OperationLogService,
	loginLogService LoginLogService,
	dataChangeLogService DataChangeLogService,
) *LogService {
	return &LogService{
		OperationLog:  operationLogService,
		LoginLog:      loginLogService,
		DataChangeLog: dataChangeLogService,
	}
}

// GetLogCleanupServiceFromApp 从应用中获取日志清理服务
func GetLogCleanupServiceFromApp(app any) LogCleanupService {
	// 这里需要根据实际的app结构来获取
	// 暂时返回nil，实际使用时需要实现
	return nil
}