Fix bug with 'й' letter and prevent blank filenames

.github/workflows/ci.yml

@@ -6,8 +6,6 @@ name: Go CI/CD Pipeline
     branches:
       - main
   pull_request:
-    branches:
-      - main
 
 jobs:
   editorconfig:
@@ -21,7 +19,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
       - uses: DavidAnson/markdownlint-cli2-action@v16
         with:
           globs: '**/*.md'
@@ -30,7 +28,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
       - name: Set up Go
         uses: actions/setup-go@v5
         with:
@@ -59,7 +57,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Set up Python
         uses: actions/setup-python@v5

src/umom/processors/mp3_filename_processor.go

@@ -4,6 +4,7 @@ import (
 	"log"
 	"os"
 	"path/filepath"
+	"unicode/utf8"
 
 	id3v2 "github.com/bogem/id3v2/v2"
 )
@@ -22,17 +23,31 @@ func ProcessMP3FileName(path string) (newFilePath string, err error) {
 	title := mp3File.Title()
 	mp3File.Close()
 
+	if artist == "" || title == "" {
+		log.Printf("Skipping renaming since %s does not have artist or title tags.\n", path)
+		return path, nil
+	}
+
 	newFileName := artist + " - " + title + ".mp3"
 	dir := filepath.Dir(path)
+	originalFileName := filepath.Base(path)
 	newFilePath = filepath.Join(dir, newFileName)
 
 	// Skip remaming if the new file name is the same as the existing one
-	if path == newFilePath {
+	// In Go, string comparison is based on byte comparison by default, not on
+	// Unicode code points. This can lead to unexpected behavior when dealing
+	// with non-ASCII characters.
+
+	// Convert strings to runes
+	r1, _ := utf8.DecodeRuneInString(originalFileName)
+	r2, _ := utf8.DecodeRuneInString(newFileName)
+
+	if r1 == r2 {
 		// log.Printf("Skipping renaming since %s already has the correct name.\n", path)
 		return path, nil
 	}
 
-	log.Printf("Renaming %s to %s\n", path, newFileName)
+	log.Printf("Renaming %q to %q\n", originalFileName, newFileName)
 
 	// Rename the file
 	if err := os.Rename(path, newFilePath); err != nil {

src/umom/processors/mp3_tags_processor.go

@@ -68,6 +68,7 @@ func normalizeTags(tag *id3v2.Tag) error {
 	return nil
 }
 
+// SUGGEST: should I add here \t\n\r\f\v characters?
 var forbiddenChars = regexp.MustCompile(`[<>:"/\\|?*]`) // Windows forbidden characters
 
 // Converts tags to UTF-16 encoding

src/umom/processors/mp3_tags_processor_test.go

@@ -28,7 +28,7 @@ func TestProcessMP3FileTags(t *testing.T) {
 	tag.SetTitle(" Xtal ")
 
 	comment := id3v2.CommentFrame{
-		Encoding:    id3v2.EncodingUTF8,
+		Encoding:    id3v2.EncodingUTF16,
 		Language:    "eng",
 		Description: "My opinion",
 		Text:        "I like this song!",