igdb: auto-refresh twitch token; category -> game_type filter

Static app tokens expire after ~60 days -> every lookup failed with
401. With igdb-client-secret set, the bot fetches the token via
client-credentials OAuth itself, refreshes a day before expiry and
retries once on 401; a static igdb-access-token still works.

IGDB renamed games.category to game_type: the category = 0 filter in
search_games silently matched nothing even with a valid token.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tests/test_igdblib.py

@@ -160,7 +160,7 @@ class TestIGDBQuery(unittest.TestCase):
             "id",
             "name",
             "alternative_names",
-            "category",
+            "game_type",
             "release_dates",
             "franchise",
             "language_supports",
@@ -174,5 +174,85 @@ class TestIGDBQuery(unittest.TestCase):
         self.assertEqual(result, [{"id": 1, "name": "Super Mario Bros"}])
 
 
+class TestIGDBTokenRefresh(unittest.TestCase):
+    @staticmethod
+    def _oauth_response(token="fresh_token", expires_in=5_000_000):
+        response = Mock()
+        response.json.return_value = {"access_token": token, "expires_in": expires_in}
+        response.raise_for_status.return_value = None
+        return response
+
+    @staticmethod
+    def _api_response(payload, status_code=200):
+        response = Mock()
+        response.status_code = status_code
+        response.json.return_value = payload
+        response.raise_for_status.return_value = None
+        return response
+
+    @patch("fjerkroa_bot.igdblib.requests.post")
+    def test_fetches_token_when_only_secret_configured(self, mock_post):
+        """Without a static token, the first request fetches one via Twitch OAuth."""
+        mock_post.side_effect = [self._oauth_response(), self._api_response([{"id": 1}])]
+        igdb = IGDBQuery("cid", client_secret="secret")
+
+        result = igdb.send_igdb_request("games", "fields name; limit 1;")
+
+        self.assertEqual(result, [{"id": 1}])
+        oauth_call, api_call = mock_post.call_args_list
+        self.assertEqual(oauth_call.args[0], "https://id.twitch.tv/oauth2/token")
+        self.assertEqual(
+            oauth_call.kwargs["params"],
+            {"client_id": "cid", "client_secret": "secret", "grant_type": "client_credentials"},
+        )
+        self.assertEqual(api_call.kwargs["headers"]["Authorization"], "Bearer fresh_token")
+
+    @patch("fjerkroa_bot.igdblib.requests.post")
+    def test_refreshes_and_retries_on_401(self, mock_post):
+        """A 401 with a configured secret triggers one refresh and retry."""
+        mock_post.side_effect = [
+            self._api_response(None, status_code=401),
+            self._oauth_response(),
+            self._api_response([{"id": 2}]),
+        ]
+        igdb = IGDBQuery("cid", "expired_token", client_secret="secret")
+
+        result = igdb.send_igdb_request("games", "fields name; limit 1;")
+
+        self.assertEqual(result, [{"id": 2}])
+        self.assertEqual(igdb.igdb_api_key, "fresh_token")
+        self.assertEqual(mock_post.call_args_list[2].kwargs["headers"]["Authorization"], "Bearer fresh_token")
+
+    @patch("fjerkroa_bot.igdblib.time.time")
+    @patch("fjerkroa_bot.igdblib.requests.post")
+    def test_proactive_refresh_before_expiry(self, mock_post, mock_time):
+        """An expired self-fetched token is refreshed before the request."""
+        mock_time.return_value = 1_000_000.0
+        mock_post.side_effect = [self._oauth_response("token_a", expires_in=5_000_000), self._api_response([])]
+        igdb = IGDBQuery("cid", client_secret="secret")
+        igdb.send_igdb_request("games", "fields name;")
+
+        # jump past the token expiry -> next request refreshes first
+        mock_time.return_value = 1_000_000.0 + 5_000_000
+        mock_post.side_effect = [self._oauth_response("token_b"), self._api_response([])]
+        igdb.send_igdb_request("games", "fields name;")
+
+        self.assertEqual(igdb.igdb_api_key, "token_b")
+
+    @patch("fjerkroa_bot.igdblib.requests.post")
+    def test_no_refresh_without_secret(self, mock_post):
+        """Static-token setups keep the old behavior: no OAuth calls, error -> None."""
+        response = Mock()
+        response.status_code = 401
+        response.raise_for_status.side_effect = requests.RequestException("401 Client Error")
+        mock_post.return_value = response
+        igdb = IGDBQuery("cid", "expired_token")
+
+        result = igdb.send_igdb_request("games", "fields name; limit 1;")
+
+        self.assertIsNone(result)
+        mock_post.assert_called_once()
+
+
 if __name__ == "__main__":
     unittest.main()