Handle case sensitive file moves (#1427)

pkg/manager/task_scan.go

@@ -72,6 +72,11 @@ func (j *ScanJob) Execute(ctx context.Context, progress *job.Progress) {
 	var galleries []string
 
 	for _, sp := range paths {
+		csFs, er := utils.IsFsPathCaseSensitive(sp.Path)
+		if er != nil {
+			logger.Warnf("Cannot determine fs case sensitivity: %s", er.Error())
+		}
+
 		err = walkFilesToScan(sp, func(path string, info os.FileInfo, err error) error {
 			if job.IsCancelled(ctx) {
 				return stoppingErr
@@ -96,6 +101,7 @@ func (j *ScanJob) Execute(ctx context.Context, progress *job.Progress) {
 				GenerateSprite:       utils.IsTrue(input.ScanGenerateSprites),
 				GeneratePhash:        utils.IsTrue(input.ScanGeneratePhashes),
 				progress:             progress,
+				CaseSensitiveFs:      csFs,
 			}
 
 			go func() {
@@ -207,6 +213,7 @@ type ScanTask struct {
 	GenerateImagePreview bool
 	zipGallery           *models.Gallery
 	progress             *job.Progress
+	CaseSensitiveFs      bool
 }
 
 func (t *ScanTask) Start(wg *sizedwaitgroup.SizedWaitGroup) {
@@ -397,6 +404,14 @@ func (t *ScanTask) scanGallery() {
 			g, _ = qb.FindByChecksum(checksum)
 			if g != nil {
 				exists, _ := utils.FileExists(g.Path.String)
+				if !t.CaseSensitiveFs {
+					// #1426 - if file exists but is a case-insensitive match for the
+					// original filename, then treat it as a move
+					if exists && strings.EqualFold(t.FilePath, g.Path.String) {
+						exists = false
+					}
+				}
+
 				if exists {
 					logger.Infof("%s already exists.  Duplicate of %s ", t.FilePath, g.Path.String)
 				} else {
@@ -749,6 +764,14 @@ func (t *ScanTask) scanScene() *models.Scene {
 
 	if s != nil {
 		exists, _ := utils.FileExists(s.Path)
+		if !t.CaseSensitiveFs {
+			// #1426 - if file exists but is a case-insensitive match for the
+			// original filename, then treat it as a move
+			if exists && strings.EqualFold(t.FilePath, s.Path) {
+				exists = false
+			}
+		}
+
 		if exists {
 			logger.Infof("%s already exists. Duplicate of %s", t.FilePath, s.Path)
 		} else {
@@ -1034,6 +1057,14 @@ func (t *ScanTask) scanImage() {
 
 		if i != nil {
 			exists := image.FileExists(i.Path)
+			if !t.CaseSensitiveFs {
+				// #1426 - if file exists but is a case-insensitive match for the
+				// original filename, then treat it as a move
+				if exists && strings.EqualFold(t.FilePath, i.Path) {
+					exists = false
+				}
+			}
+
 			if exists {
 				logger.Infof("%s already exists.  Duplicate of %s ", image.PathDisplayName(t.FilePath), image.PathDisplayName(i.Path))
 			} else {

pkg/utils/file.go

@@ -306,3 +306,43 @@ func GetFunscriptPath(path string) string {
 	fn := strings.TrimSuffix(path, ext)
 	return fn + ".funscript"
 }
+
+// IsFsPathCaseSensitive checks the fs of the given path to see if it is case sensitive
+// if the case sensitivity can not be determined false and an error != nil are returned
+func IsFsPathCaseSensitive(path string) (bool, error) {
+	// The case sensitivity of the fs of "path" is determined by case flipping
+	// the first letter rune from the base string of the path
+	// If the resulting flipped path exists then the fs should not be case sensitive
+	// ( we check the file mod time to avoid matching an existing path )
+
+	fi, err := os.Stat(path)
+	if err != nil { // path cannot be stat'd
+		return false, err
+	}
+
+	base := filepath.Base(path)
+	fBase, err := FlipCaseSingle(base)
+	if err != nil { // cannot be case flipped
+		return false, err
+	}
+	i := strings.LastIndex(path, base)
+	if i < 0 { // shouldn't happen
+		return false, fmt.Errorf("could not case flip path %s", path)
+	}
+
+	flipped := []byte(path)
+	for _, c := range []byte(fBase) { // replace base of path with the flipped one ( we need to flip the base or last dir part )
+		flipped[i] = c
+		i++
+	}
+
+	fiCase, err := os.Stat(string(flipped))
+	if err != nil { // cannot stat the case flipped path
+		return true, nil // fs of path should be case sensitive
+	}
+
+	if fiCase.ModTime() == fi.ModTime() { // file path exists and is the same
+		return false, nil // fs of path is not case sensitive
+	}
+	return false, fmt.Errorf("can not determine case sensitivity of path %s", path)
+}

pkg/utils/strings.go

@@ -5,6 +5,7 @@ import (
 	"math/rand"
 	"strings"
 	"time"
+	"unicode"
 )
 
 var characters = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890")
@@ -18,8 +19,37 @@ func RandomSequence(n int) string {
 	return string(b)
 }
 
+// FlipCaseSingle flips the case ( lower<->upper ) of a single char from the string s
+// If the string cannot be flipped, the original string value and an error are returned
+func FlipCaseSingle(s string) (string, error) {
+	rr := []rune(s)
+	for i, r := range rr {
+		if unicode.IsLetter(r) { // look for a letter  to flip
+			if unicode.IsUpper(r) {
+				rr[i] = unicode.ToLower(r)
+				return string(rr), nil
+			}
+			rr[i] = unicode.ToUpper(r)
+			return string(rr), nil
+		}
+
+	}
+	return s, fmt.Errorf("could not case flip string %s", s)
+}
+
 type StrFormatMap map[string]interface{}
 
+// StrFormat formats the provided format string, replacing placeholders
+// in the form of "{fieldName}" with the values in the provided
+// StrFormatMap.
+//
+// For example,
+// StrFormat("{foo} bar {baz}", StrFormatMap{
+//     "foo": "bar",
+//     "baz": "abc",
+// })
+//
+// would return: "bar bar abc"
 func StrFormat(format string, m StrFormatMap) string {
 	args := make([]string, len(m)*2)
 	i := 0

ui/v2.5/src/components/Changelog/versions/v080.md

@@ -19,6 +19,7 @@
 * Add button to remove studio stash ID. ([#1378](https://github.com/stashapp/stash/pull/1378))
 
 ### 🐛 Bug fixes
+* Fix file move detection when case of filename is changed on case-insensitive file systems. ([#1426](https://github.com/stashapp/stash/issues/1426))
 * Fix auto-tagger not tagging scenes with no whitespace in name. ([#1488](https://github.com/stashapp/stash/pull/1488))
 * Fix click/drag to select scenes. ([#1476](https://github.com/stashapp/stash/pull/1476))
 * Fix clearing Performer and Movie ratings not working. ([#1429](https://github.com/stashapp/stash/pull/1429))