refactor(fs): move ReplaceMagicVar to fs with named props; drop dead helpers

ReplaceMagicVar only had filemanager callers and took 9 positional
params (three same-typed strings, two adjacent bools). It now lives in
pkg/filemanager/fs taking a named MagicVarProps. BuildRegexp,
BuildConcat and the asymmetric EncodeTimeFlowString pair had no
production callers — deleted along with their tests.

Authored By: TDvorak <info@tdvorak.dev>

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

pkg/filemanager/fs/dbfs/dbfs.go

@@ -22,7 +22,6 @@ import (
 	"github.com/cloudreve/Cloudreve/v4/pkg/logging"
 	"github.com/cloudreve/Cloudreve/v4/pkg/serializer"
 	"github.com/cloudreve/Cloudreve/v4/pkg/setting"
-	"github.com/cloudreve/Cloudreve/v4/pkg/util"
 	"github.com/gofrs/uuid"
 	"github.com/samber/lo"
 	"math"
@@ -855,7 +854,14 @@ func (f *DBFS) navigatorId(path *fs.URI) string {
 func generateSavePath(policy *ent.StoragePolicy, req *fs.UploadRequest, user *ent.User) string {
 	currentTime := time.Now()
 	dynamicReplace := func(rule string, pathAvailable bool) string {
-		return util.ReplaceMagicVar(rule, fs.Separator, pathAvailable, false, currentTime, user.ID, req.Props.Uri.Name(), req.Props.Uri.Dir(), "")
+		return fs.ReplaceMagicVar(rule, fs.MagicVarProps{
+			FsSeparator:   fs.Separator,
+			PathAvailable: pathAvailable,
+			Time:          currentTime,
+			UserID:        user.ID,
+			OriginName:    req.Props.Uri.Name(),
+			OriginPath:    req.Props.Uri.Dir(),
+		})
 	}
 
 	dirRule := policy.DirNameRule

pkg/filemanager/fs/dbfs/upload.go

@@ -178,7 +178,16 @@ func (f *DBFS) PrepareUpload(ctx context.Context, req *fs.UploadRequest, opts ..
 	if req.Props.SavePath == "" || isThumbnailAndPolicyNotAvailable {
 		req.Props.SavePath = generateSavePath(policy, req, f.user)
 		if isThumbnailAndPolicyNotAvailable {
-			req.Props.SavePath = path.Clean(util.ReplaceMagicVar(f.settingClient.ThumbEntitySuffix(ctx), fs.Separator, true, true, time.Now(), f.user.ID, req.Props.Uri.Name(), req.Props.Uri.Path(), req.Props.SavePath))
+			req.Props.SavePath = path.Clean(fs.ReplaceMagicVar(f.settingClient.ThumbEntitySuffix(ctx), fs.MagicVarProps{
+				FsSeparator:      fs.Separator,
+				PathAvailable:    true,
+				BlobAvailable:    true,
+				Time:             time.Now(),
+				UserID:           f.user.ID,
+				OriginName:       req.Props.Uri.Name(),
+				OriginPath:       req.Props.Uri.Path(),
+				CompleteBlobPath: req.Props.SavePath,
+			}))
 		}
 	}
 

pkg/filemanager/fs/magicvar.go

@@ -0,0 +1,101 @@
+package fs
+
+import (
+	"math/rand"
+	"path"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/cloudreve/Cloudreve/v4/pkg/util"
+	"github.com/gofrs/uuid"
+)
+
+// MagicVarProps carries the context available to magic-variable expansion in
+// path templates.
+type MagicVarProps struct {
+	FsSeparator      string
+	PathAvailable    bool
+	BlobAvailable    bool
+	Time             time.Time
+	UserID           int
+	OriginName       string
+	OriginPath       string
+	CompleteBlobPath string
+}
+
+var magicVarRe = regexp.MustCompile(`\{[^{}]+\}`)
+
+// ReplaceMagicVar expands {var} placeholders in rawString using p.
+func ReplaceMagicVar(rawString string, p MagicVarProps) string {
+	return magicVarRe.ReplaceAllStringFunc(rawString, func(match string) string {
+		switch match {
+		case "{randomkey16}":
+			return util.RandStringRunes(16)
+		case "{randomkey8}":
+			return util.RandStringRunes(8)
+		case "{timestamp}":
+			return strconv.FormatInt(p.Time.Unix(), 10)
+		case "{timestamp_nano}":
+			return strconv.FormatInt(p.Time.UnixNano(), 10)
+		case "{randomnum2}":
+			return strconv.Itoa(rand.Intn(2))
+		case "{randomnum3}":
+			return strconv.Itoa(rand.Intn(3))
+		case "{randomnum4}":
+			return strconv.Itoa(rand.Intn(4))
+		case "{randomnum8}":
+			return strconv.Itoa(rand.Intn(8))
+		case "{uid}":
+			return strconv.Itoa(p.UserID)
+		case "{datetime}":
+			return p.Time.Format("20060102150405")
+		case "{date}":
+			return p.Time.Format("20060102")
+		case "{year}":
+			return p.Time.Format("2006")
+		case "{month}":
+			return p.Time.Format("01")
+		case "{day}":
+			return p.Time.Format("02")
+		case "{hour}":
+			return p.Time.Format("15")
+		case "{minute}":
+			return p.Time.Format("04")
+		case "{second}":
+			return p.Time.Format("05")
+		case "{uuid}":
+			return uuid.Must(uuid.NewV4()).String()
+		case "{ext}":
+			return filepath.Ext(p.OriginName)
+		case "{originname}":
+			return p.OriginName
+		case "{originname_without_ext}":
+			return strings.TrimSuffix(p.OriginName, filepath.Ext(p.OriginName))
+		case "{path}":
+			if p.PathAvailable {
+				return p.OriginPath + p.FsSeparator
+			}
+			return match
+		case "{blob_name}":
+			if p.BlobAvailable {
+				return filepath.Base(p.CompleteBlobPath)
+			}
+			return match
+		case "{blob_name_without_ext}":
+			if p.BlobAvailable {
+				return strings.TrimSuffix(filepath.Base(p.CompleteBlobPath), filepath.Ext(p.CompleteBlobPath))
+			}
+			return match
+		case "{blob_path}":
+			if p.BlobAvailable {
+				return path.Dir(p.CompleteBlobPath) + p.FsSeparator
+			}
+			return match
+		default:
+			return match
+		}
+	})
+}

pkg/filemanager/fs/magicvar_test.go

@@ -0,0 +1,48 @@
+package fs
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestReplaceMagicVar(t *testing.T) {
+	a := assert.New(t)
+	now := time.Date(2024, 3, 5, 6, 7, 8, 0, time.UTC)
+	props := MagicVarProps{
+		FsSeparator:      "/",
+		PathAvailable:    true,
+		BlobAvailable:    true,
+		Time:             now,
+		UserID:           42,
+		OriginName:       "photo.jpg",
+		OriginPath:       "album/2024",
+		CompleteBlobPath: "blobs/abc123.bin",
+	}
+
+	a.Equal("u42", ReplaceMagicVar("u{uid}", props))
+	a.Equal("20240305", ReplaceMagicVar("{date}", props))
+	a.Equal("20240305060708", ReplaceMagicVar("{datetime}", props))
+	a.Equal("2024/03/05", ReplaceMagicVar("{year}/{month}/{day}", props))
+	a.Equal("photo.jpg", ReplaceMagicVar("{originname}", props))
+	a.Equal("photo", ReplaceMagicVar("{originname_without_ext}", props))
+	a.Equal(".jpg", ReplaceMagicVar("{ext}", props))
+	a.Equal("album/2024/", ReplaceMagicVar("{path}", props))
+	a.Equal("abc123.bin", ReplaceMagicVar("{blob_name}", props))
+	a.Equal("abc123", ReplaceMagicVar("{blob_name_without_ext}", props))
+	a.Equal("blobs/", ReplaceMagicVar("{blob_path}", props))
+	a.Equal("{unknown}", ReplaceMagicVar("{unknown}", props))
+
+	// Unavailable context leaves the placeholder untouched.
+	noPath := props
+	noPath.PathAvailable = false
+	a.Equal("{path}", ReplaceMagicVar("{path}", noPath))
+	noBlob := props
+	noBlob.BlobAvailable = false
+	a.Equal("{blob_name}", ReplaceMagicVar("{blob_name}", noBlob))
+
+	// Random vars produce non-empty output.
+	a.Len(ReplaceMagicVar("{randomkey8}", props), 8)
+	a.Len(ReplaceMagicVar("{uuid}", props), 36)
+}

pkg/filemanager/manager/thumbnail.go

@@ -186,7 +186,16 @@ func (m *manager) generateThumb(ctx context.Context, uri *fs.URI, ext string, es
 			Props: &fs.UploadProps{
 				Uri:  uri,
 				Size: fileInfo.Size(),
-				SavePath:   path.Clean(util.ReplaceMagicVar(m.settings.ThumbEntitySuffix(ctx), fs.Separator, true, true, time.Now(), m.user.ID, uri.Name(), uri.Path(), es.Entity().Source())),
+				SavePath: path.Clean(fs.ReplaceMagicVar(m.settings.ThumbEntitySuffix(ctx), fs.MagicVarProps{
+					FsSeparator:      fs.Separator,
+					PathAvailable:    true,
+					BlobAvailable:    true,
+					Time:             time.Now(),
+					UserID:           m.user.ID,
+					OriginName:       uri.Name(),
+					OriginPath:       uri.Path(),
+					CompleteBlobPath: es.Entity().Source(),
+				})),
 				MimeType:   m.dep.MimeDetector(ctx).TypeByName("thumb.jpg"),
 				EntityType: &entityType,
 			},

pkg/util/common.go

@@ -5,15 +5,10 @@ import (
 	cryptoRand "crypto/rand"
 	"math/big"
 	"math/rand"
-	"path"
-	"path/filepath"
-	"regexp"
-	"strconv"
 	"strings"
 	"time"
 
 	"github.com/gin-gonic/gin"
-	"github.com/gofrs/uuid"
 )
 
 func init() {
@@ -114,102 +109,6 @@ func Replace(table map[string]string, s string) string {
 	return s
 }
 
-// ReplaceMagicVar 动态替换字符串中的魔法变量
-func ReplaceMagicVar(rawString string, fsSeparator string, pathAvailable bool, blobAvailable bool,
-	timeConst time.Time, userId int, originName string, originPath string, completeBlobPath string) string {
-	re := regexp.MustCompile(`\{[^{}]+\}`)
-	return re.ReplaceAllStringFunc(rawString, func(match string) string {
-		switch match {
-		case "{randomkey16}":
-			return RandStringRunes(16)
-		case "{randomkey8}":
-			return RandStringRunes(8)
-		case "{timestamp}":
-			return strconv.FormatInt(timeConst.Unix(), 10)
-		case "{timestamp_nano}":
-			return strconv.FormatInt(timeConst.UnixNano(), 10)
-		case "{randomnum2}":
-			return strconv.Itoa(rand.Intn(2))
-		case "{randomnum3}":
-			return strconv.Itoa(rand.Intn(3))
-		case "{randomnum4}":
-			return strconv.Itoa(rand.Intn(4))
-		case "{randomnum8}":
-			return strconv.Itoa(rand.Intn(8))
-		case "{uid}":
-			return strconv.Itoa(userId)
-		case "{datetime}":
-			return timeConst.Format("20060102150405")
-		case "{date}":
-			return timeConst.Format("20060102")
-		case "{year}":
-			return timeConst.Format("2006")
-		case "{month}":
-			return timeConst.Format("01")
-		case "{day}":
-			return timeConst.Format("02")
-		case "{hour}":
-			return timeConst.Format("15")
-		case "{minute}":
-			return timeConst.Format("04")
-		case "{second}":
-			return timeConst.Format("05")
-		case "{uuid}":
-			return uuid.Must(uuid.NewV4()).String()
-		case "{ext}":
-			return filepath.Ext(originName)
-		case "{originname}":
-			return originName
-		case "{originname_without_ext}":
-			return strings.TrimSuffix(originName, filepath.Ext(originName))
-		case "{path}":
-			if pathAvailable {
-				return originPath + fsSeparator
-			}
-			return match
-		case "{blob_name}":
-			if blobAvailable {
-				return filepath.Base(completeBlobPath)
-			}
-			return match
-		case "{blob_name_without_ext}":
-			if blobAvailable {
-				return strings.TrimSuffix(filepath.Base(completeBlobPath), filepath.Ext(completeBlobPath))
-			}
-			return match
-		case "{blob_path}":
-			if blobAvailable {
-				return path.Dir(completeBlobPath) + fsSeparator
-			}
-			return match
-		default:
-			return match
-		}
-	})
-}
-
-// BuildRegexp 构建用于SQL查询用的多条件正则
-func BuildRegexp(search []string, prefix, suffix, condition string) string {
-	var res string
-	for key, value := range search {
-		res += prefix + regexp.QuoteMeta(value) + suffix
-		if key < len(search)-1 {
-			res += condition
-		}
-	}
-	return res
-}
-
-// BuildConcat 根据数据库类型构建字符串连接表达式
-func BuildConcat(str1, str2 string, DBType string) string {
-	switch DBType {
-	case "mysql":
-		return "CONCAT(" + str1 + "," + str2 + ")"
-	default:
-		return str1 + "||" + str2
-	}
-}
-
 // SliceIntersect 求两个切片交集
 func SliceIntersect(slice1, slice2 []string) []string {
 	m := make(map[string]int)

pkg/util/common_test.go

@@ -56,19 +56,6 @@ func TestReplace(t *testing.T) {
 	}, "123origin123"))
 }
 
-func TestBuildRegexp(t *testing.T) {
-	asserts := assert.New(t)
-
-	asserts.Equal("^/dir/", BuildRegexp([]string{"/dir"}, "^", "/", "|"))
-	asserts.Equal("^/dir/|^/dir/di\\*r/", BuildRegexp([]string{"/dir", "/dir/di*r"}, "^", "/", "|"))
-}
-
-func TestBuildConcat(t *testing.T) {
-	asserts := assert.New(t)
-	asserts.Equal("CONCAT(1,2)", BuildConcat("1", "2", "mysql"))
-	asserts.Equal("1||2", BuildConcat("1", "2", "sqlite"))
-}
-
 func TestSliceDifference(t *testing.T) {
 	asserts := assert.New(t)