refactor: replace functions.GetMediaFileNameWithId with tgutil.GetMediaFileName for better media file name handling

common/utils/tgutil/media.go

@@ -0,0 +1,40 @@
+package tgutil
+
+import (
+	"fmt"
+
+	"github.com/gabriel-vasile/mimetype"
+	"github.com/gotd/td/tg"
+)
+
+func GetMediaFileName(media tg.MessageMediaClass) (string, error) {
+	switch v := media.(type) {
+	case *tg.MessageMediaPhoto:
+		f, ok := v.Photo.AsNotEmpty()
+		if !ok {
+			return "", fmt.Errorf("unknown type media: %T", media)
+		}
+		return fmt.Sprintf("%d.png", f.ID), nil
+	case *tg.MessageMediaDocument:
+		f, ok := v.Document.AsNotEmpty()
+		if !ok {
+			return "", fmt.Errorf("unknown type media: %T", media)
+		}
+		fileName := ""
+		for _, attribute := range f.Attributes {
+			if name, ok := attribute.(*tg.DocumentAttributeFilename); ok {
+				fileName = name.GetFileName()
+				break
+			}
+		}
+		if fileName == "" {
+			mmt := mimetype.Lookup(f.GetMimeType())
+			if mmt != nil {
+				fileName = fmt.Sprintf("%d.%s", f.GetID(), mmt.Extension())
+			}
+		}
+		return fileName, nil
+	default:
+		return "", fmt.Errorf("unsupported type media: %T", media)
+	}
+}

common/utils/tgutil/message.go

@@ -6,7 +6,6 @@ import (
 	"strings"
 
 	"github.com/celestix/gotgproto/ext"
-	"github.com/celestix/gotgproto/functions"
 	"github.com/duke-git/lancet/v2/maputil"
 
 	"github.com/duke-git/lancet/v2/mathutil"
@@ -86,7 +85,7 @@ func GenFileNameFromMessage(message tg.Message) string {
 	}()
 
 	if filename == "" {
-		mname, err := functions.GetMediaFileNameWithId(message.Media)
+		mname, err := GetMediaFileName(message.Media)
 		if err != nil {
 			filename = fmt.Sprintf("%d_%s", message.GetID(), xid.New().String())
 		} else {