/**
  * Store a newly created resource in storage.
  *
  * @param  \Illuminate\Http\Request  $request
  * @return \Illuminate\Http\Response
  */
 public function store(Request $request)
 {
     //
     $input = $request->all();
     $comment = Comment::where('user_id_from', '=', $input['user_id_from'])->where('user_id_to', '=', $input['user_id_to'])->first();
     if ($comment == null) {
         $comment = new Comment();
         $user_from = User::where('facebook_id', '=', $input['user_id_from'])->first();
         $user_to = User::where('facebook_id', '=', $input['user_id_to'])->first();
         if (!$comment->userTo()->associate($user_to)) {
             return response()->json(array('status' => 'error'));
         }
         if (!$comment->userFrom()->associate($user_from)) {
             return response()->json(array('status' => 'error'));
         }
     }
     $comment->comment = $input['comment'];
     if ($comment->save()) {
         return response()->json(array('status' => 'ok'));
     }
     return response()->json(array('status' => 'error'));
 }