package path

import (
	"fmt"
	"os"
	"sync"
	"time"

	"git.lhk.o-r.kr/freerer2/simple_backup/internal/constants"
)

// GetGroupByFolder generates a simple_backup path based on the groupBy option and time.
// If groupBy is invalid or empty, it returns the basePath unchanged.
//
// Parameters:
//   - basePath: the base directory path for simple_backup
//   - groupBy: grouping option (year, mon, day, hour, min, sec)
//   - t: time to use for path generation
//
// Returns:
//   - string: generated path based on groupBy option
func GetGroupByFolder(basePath, groupBy string, t time.Time) string {
	switch groupBy {
	case constants.GroupByYear:
		return fmt.Sprintf("%s/%d", basePath, t.Year())
	case constants.GroupByMonth:
		return fmt.Sprintf("%s/%d%02d", basePath, t.Year(), t.Month())
	case constants.GroupByDay:
		return fmt.Sprintf("%s/%d%02d%02d", basePath, t.Year(), t.Month(), t.Day())
	case constants.GroupByHour:
		return fmt.Sprintf("%s/%d%02d%02d_%02d", basePath, t.Year(), t.Month(), t.Day(), t.Hour())
	case constants.GroupByMin:
		return fmt.Sprintf("%s/%d%02d%02d_%02d%02d", basePath, t.Year(), t.Month(), t.Day(), t.Hour(), t.Minute())
	case constants.GroupBySec:
		return fmt.Sprintf("%s/%d%02d%02d_%02d%02d%02d", basePath, t.Year(), t.Month(), t.Day(), t.Hour(), t.Minute(), t.Second())
	case "":
		return basePath
	default:
		fmt.Printf("지원하지 않는 group-by 옵션입니다: %s\n", groupBy)
		return basePath
	}
}

// 디렉토리 캐시
type DirCache struct {
	sync.RWMutex
	exists map[string]bool
}

func NewDirCache() *DirCache {
	return &DirCache{
		exists: make(map[string]bool),
	}
}

func (c *DirCache) EnsureDir(path string) error {
	c.RLock()
	if c.exists[path] {
		c.RUnlock()
		return nil
	}
	c.RUnlock()

	c.Lock()
	defer c.Unlock()

	// 다시 확인 (다른 고루틴이 생성했을 수 있음)
	if c.exists[path] {
		return nil
	}

	if err := os.MkdirAll(path, constants.DefaultFileMode); err != nil {
		return err
	}

	c.exists[path] = true
	return nil
}