Validate moves and erase errors from terminal

chesscli.py

@@ -1,14 +1,36 @@
 import chess
 import chess.engine
+import urllib.parse
+
+# Check if input is a valid SAN move
+def is_valid_san(board, raw_move):
+    try:
+        board.parse_san(raw_move)
+        return True
+    except ValueError:
+        return False
 
 board = chess.Board()
 engine = chess.engine.SimpleEngine.popen_uci("bin/stockfish")
+engine.configure({"Skill Level": 1})
 count = 1
+error = False
 
 while not board.is_game_over():
     if board.turn == chess.WHITE:
-        move = input(str(count) + " ")
-        board.push_san(move)
+        raw_move = input(str(count) + " ")
+        valid_move = is_valid_san(board, raw_move)
+        if error:
+            for _ in range(4):
+                print("\033[F\033[K", end="")
+            print(str(count) + " " + raw_move)
+            error = False
+        if not valid_move:
+            print("Sorry, but '" + raw_move + "' is not a valid move")
+            print("See board: https://lichess.org/analysis/" + urllib.parse.quote(board.fen()))
+            error = True
+        else:
+            board.push_san(raw_move)
     else:
         result = engine.play(board, chess.engine.Limit(time=2.0))
         print(str(count) +  "...", board.san(result.move))