v1.0.5 confirm tags exist when scanning for tags

main.go

@@ -71,7 +71,10 @@ func getDir() (string, error) {
 	if len(os.Args) > 1 {
 		return os.Args[1], nil
 	} else {
-		dataArg := os.Getenv("SLSKD_SCRIPT_DATA")
+		dataArg, found := os.LookupEnv("SLSKD_SCRIPT_DATA")
+		if !found {
+			return "", errors.New("missing any reference to a path")
+		}
 		var data DownloadDirectoryComplete
 		if err := json.Unmarshal([]byte(dataArg), &data); err != nil {
 			return "", err
@@ -155,6 +158,7 @@ func getTagsInDir(directory string) (tag.Metadata, error) {
 		return nil, err
 	}
 
+	missingTags := false
 	for _, file := range files {
 		fname := path.Join(directory, file.Name())
 
@@ -173,12 +177,30 @@ func getTagsInDir(directory string) (tag.Metadata, error) {
 			continue
 		}
 
+		// if we found tags but they're incomplete, switch the flag
+		if !checkTags(tags) {
+			missingTags = true
+			continue
+		}
+
 		// found tag data
 		return tags, nil
 	}
 	
 	// no tag data in any file
-	return nil, errors.New("missing tag data")
+	if missingTags {
+		return nil, errors.New("files have incomplete tag data")
+	} else {
+		return nil, errors.New("unable to read tag data")
+	}
+}
+
+func checkTags(tags tag.Metadata) bool {
+	// most important tags
+	if tags.Album() == "" || tags.AlbumArtist() == "" || tags.Artist() == "" || tags.Title() == "" {
+		return false
+	}
+	return true
 }
 
 func doMoveNotags(directory string) error {