+/**
+ * @param {?string} fen
+ * @param {Array.<string>} moves
+ * @param {number} last_move
+ */
+var chess_from = function(fen, moves, last_move) {
+ var hiddenboard = new Chess();
+ if (fen !== null) {
+ hiddenboard.load(fen);
+ }
+ for (var i = 0; i <= last_move; ++i) {
+ if (moves[i] === '0-0') {
+ hiddenboard.move('O-O');
+ } else if (moves[i] === '0-0-0') {
+ hiddenboard.move('O-O-O');
+ } else {
+ hiddenboard.move(moves[i]);
+ }
+ }
+ return hiddenboard;
+}
+