Fixed file moving

android/src/main/java/com/RNFetchBlob/RNFetchBlobFS.java

@@ -599,16 +599,36 @@ static void mv(String path, String dest, Callback callback) {
             callback.invoke("Source file at path `" + path + "` does not exist");
             return;
         }
+
+        //Check if the output file directory exists.
+        File dir = new File(dest);
+        if (!dir.exists())
+        {
+            dir.mkdirs();
+        }
+
         try {
-            boolean result = src.renameTo(new File(dest));
-            if (!result) {
-                callback.invoke("mv failed for unknown reasons");
-                return;
+            InputStream in = new FileInputStream(path);
+            OutputStream out = new FileOutputStream(dest);
+
+            //read source path to byte buffer. Write from input to output stream
+            byte[] buffer = new byte[1024];
+            int read;
+            while ((read = in.read(buffer)) != -1) { //read is successful
+                out.write(buffer, 0, read);
             }
+            in.close();
+            out.flush();
+
+            src.delete(); //remove original file
+        } catch (FileNotFoundException exception) {
+            callback.invoke(exception.toString());
+            return;
         } catch (Exception e) {
-            callback.invoke(e.getLocalizedMessage());
+            callback.invoke(e.toString());
             return;
         }
+
         callback.invoke();
     }