diff --git a/CHESS_JSON.php b/CHESS_JSON.php
new file mode 100644
index 0000000..0f027c1
--- /dev/null
+++ b/CHESS_JSON.php
@@ -0,0 +1,38 @@
+<?php
+
+class CHESS_JSON {
+
+    const MOVE_FROM = 'from';
+    const MOVE_TO = 'to';
+    const MOVE_NOTATION = 'm';
+    const FEN = 'fen';
+    const MOVE_COMMENT = 'comment';
+    const MOVE_ACTION = 'action';
+    const MOVE_VARIATIONS = 'variations';
+    const MOVE_MOVES = 'moves';
+    const MOVE_CAPTURE = 'capture';
+    const MOVE_PROMOTE_TO = 'promoteTo';
+    const MOVE_CASTLE = 'castle';
+    const MOVE_PARSED = 'castle';
+
+    const GAME_METADATA = 'metadata';
+    const GAME_EVENT = 'event';
+    const GAME_WHITE = 'white';
+    const GAME_BLACK = 'black';
+    const GAME_ECO = 'black';
+
+
+    protected static $jsKeys = array('MOVE_FROM', 'MOVE_TO', 'MOVE_NOTATION', 'FEN','MOVE_COMMENT',
+        'MOVE_ACTION', 'MOVE_VARIATIONS', 'MOVE_MOVES','MOVE_CAPTURE','MOVE_PROMOTE_TO','MOVE_CASTLE',
+        'GAME_METADATA', 'GAME_EVENT', 'GAME_WHITE','GAME_BLACK', 'GAME_ECO',
+
+    );
+
+    public static function toJavascript(){
+        $ret = array();
+        foreach(self::$jsKeys as $key){
+            $ret[$key] = constant("CHESS_JSON::" . $key);
+        }
+        return 'ludo.CHESS_JSON_KEY = ' . json_encode($ret) .';';
+    }
+}
\ No newline at end of file