feat: added tests and gamestate for reroll shop

Author: stirby

docs/protocol-api.md

@@ -143,7 +143,7 @@ The `shop` function supports multiple in-shop actions. Use the `action` field in
 | `reroll`     | Spend dollars to refresh the shop offer (cost shown in-game). | —                                                        |
 
 !!! note "Future actions"
-Additional shop actions such as `buy_and_use_card`, `open_pack`, and `redeem_voucher` will be added in a future release.
+Additional shop actions `buy_and_use_card`, `open_pack`, and `redeem_voucher` will be added soon.
 
 ### Errors
 

src/lua/utils.lua

@@ -110,6 +110,10 @@ function utils.get_game_state()
         -- "free_rerolls": int, (default 0) -- Number  of free rerolls in the shop?
         hands_left = G.GAME.current_round.hands_left, -- Number of hands left for this round
         hands_played = G.GAME.current_round.hands_played, -- Number of hands played in this round
+
+        -- Reroll information (used in shop state)
+        reroll_cost = G.GAME.current_round.reroll_cost, -- Current cost for a shop reroll
+        free_rerolls = G.GAME.current_round.free_rerolls, -- Free rerolls remaining this round
         -- "idol_card": { -- what's a idol card?? maybe some random used by some joker/effect? idk
         --   "rank": "Ace" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" | "10" | "Jack" | "Queen" | "King",
         --   "suit": "Spades" | "Hearts" | "Diamonds" | "Clubs",

tests/lua/endpoints/test_shop.py

@@ -244,6 +244,57 @@ def test_shop_buy_card(self, tcp_client: socket.socket) -> None:
         assert purchase_response["game"]["dollars"] == 4
         assert purchase_response["jokers"]["cards"][0]["cost"] == 6
 
+    # ------------------------------------------------------------------
+    # reroll shop
+    # ------------------------------------------------------------------
+
+    def test_shop_reroll_success(self, tcp_client: socket.socket) -> None:
+        """Successful reroll keeps us in shop and updates cards / dollars."""
+
+        # Capture shop state before reroll
+        before_state = send_and_receive_api_message(tcp_client, "get_game_state", {})
+        assert before_state["state"] == State.SHOP.value
+        before_keys = [
+            c["config"]["center_key"] for c in before_state["shop_jokers"]["cards"]
+        ]
+        dollars_before = before_state["game"]["dollars"]
+        reroll_cost = before_state["game"]["current_round"]["reroll_cost"]
+
+        # Perform the reroll
+        after_state = send_and_receive_api_message(
+            tcp_client, "shop", {"action": "reroll"}
+        )
+        
+        # verify state
+        assert after_state["state"] == State.SHOP.value
+        assert after_state["game"]["dollars"] == dollars_before - reroll_cost
+        after_keys = [
+            c["config"]["center_key"] for c in after_state["shop_jokers"]["cards"]
+        ]
+        assert before_keys != after_keys
+
+    def test_shop_reroll_insufficient_dollars(self, tcp_client: socket.socket) -> None:
+        """Repeated rerolls eventually raise INVALID_ACTION when too expensive."""
+
+        # Perform rerolls until an error is returned or a reasonable max tries reached
+        max_attempts = 10
+        for _ in range(max_attempts):
+            response = send_and_receive_api_message(
+                tcp_client, "shop", {"action": "reroll"}
+            )
+
+            # Break when error encountered and validate
+            if "error" in response:
+                assert_error_response(
+                    response,
+                    "Not enough dollars to reroll",
+                    ["dollars", "reroll_cost"],
+                    ErrorCode.INVALID_ACTION.value,
+                )
+                break
+        else:
+            pytest.fail("Rerolls did not exhaust dollars within expected attempts")
+
     # ------------------------------------------------------------------
     # buy_card validation / error scenarios
     # ------------------------------------------------------------------