algorithms/a_star.py

@@ -1,9 +1,23 @@
 from __future__ import annotations
 
 from dataclasses import dataclass, field
-from typing import Tuple, Optional
+from enum import Enum, unique
+from typing import Tuple, Optional, List
 
-from common.constants import Direction
+
+@unique
+class Direction(Enum):
+    LEFT = (0, -1)
+    RIGHT = (0, 1)
+    UP = (-1, 0)
+    DOWN = (1, 0)
+
+
+@unique
+class Action(Enum):
+    TURN_LEFT = 'TURN_LEFT'
+    TURN_RIGHT = 'TURN_RIGHT'
+    FORWARD = 'FORWARD'
 
 
 @dataclass
@@ -16,10 +30,40 @@ class State:
 class Node:
     state: State
     parent: Optional[Node]
-    action: str
+    action: Action
     cost: int = field(init=False)
     depth: int = field(init=False)
 
     def __post_init__(self) -> None:
         self.cost = 0 if not self.parent else self.parent.cost + 1
         self.depth = self.cost
+
+    def __eq__(self, other: Node) -> bool:
+        return self.state == other.state
+
+    def __hash__(self) -> int:
+        return hash(self.state)
+
+
+def child_node(action: Action) -> Node:
+    pass
+
+
+def actions(state: State) -> List[str]:
+    pass
+
+
+def result(state: State, action: Action) -> State:
+    pass
+
+
+def goal_test(state: State, goal_list: List[Tuple[int, int]]) -> bool:
+    pass
+
+
+def h(state: State) -> int:
+    pass
+
+
+def f(state: State) -> int:
+    pass