Added check the current encoding of the file

~dev_rating/application/classes/FileParser.php

@@ -109,6 +109,12 @@ class FileParser
 
     public static function toUTF8($source_str) {
         // TODO: make it able to convert from any encoding to UTF-8
-        return mb_convert_encoding($source_str, "utf-8", "windows-1251");
+        $enc = mb_detect_encoding($source_str, mb_list_encodings(), true);
+        if ($enc === false)
+            return $source_str;
+        else if ($enc !== "UTF-8")
+            return mb_convert_encoding($source_str, "utf-8", "windows-1251");
+        else
+            return $source_str;
     }
 }