more error correction and stop to hit self

snakes/AStarSnake.py

@@ -101,7 +101,7 @@ class AStarSnake(TemplateSnake):
     def heuristic(a, b):
       return abs(a[0] - b[0]) + abs(a[1] - b[1])
 
-    def a_star(start, goal):
+    def a_star(start, goal:set=()):
       open_set = Queue()
       open_set.put(start)
       came_from = {}
@@ -128,9 +128,16 @@ class AStarSnake(TemplateSnake):
 
       return None
 
+    try:
       nearest_food = min(foods, key=lambda food: heuristic(my_head, (food["x"], food["y"])))
       target_position = (nearest_food["x"], nearest_food["y"])
       move_target = a_star(my_head, target_position)
+    except ValueError:
+      # TODO: What to do when no food is available?
+      # - Avoid own body and other snakes
+      # - Flut fill?
+      move_target = a_star(my_head, safe_cells)
+      print(move_target)
 
     # Choose the next move based on the path obtained from A* algorithm
     if move_target:
@@ -148,5 +155,11 @@ class AStarSnake(TemplateSnake):
         return "down"
 
     # If no safe path to food is found, choose a random move
-    self.add_to_history({"my_head": my_head, "my_body": tuple(my_body), "target": move_target, "target_position": target_position, "nearest_food": nearest_food})
+    random_move = random.choice(["up", "down", "left", "right"])
-    return random.choice(["up", "down", "left", "right"])
+
+    try:
+      self.add_to_history({"my_head": my_head, "my_body": tuple(my_body), "target": move_target, "target_position": target_position, "nearest_food": nearest_food, "random_move": random_move})
+    except UnboundLocalError:
+      self.add_to_history({"my_head": my_head, "my_body": tuple(my_body), "target": move_target, "random_move": random_move})
+
+    return random_move