20240903 pre release

lib/services/auth_service.dart

@@ -108,7 +108,22 @@ class AuthService {
       if (response.statusCode == 200) {
         cats = json.decode(utf8.decode(response.bodyBytes));
       } else {
+        debugPrint('Response body: ${response.body}');
+
         print('Login failed with status code: ${response.statusCode}');
+        var errorMessage = 'ログインに失敗しました。';
+        if (response.statusCode == 400) {
+          var errorBody = json.decode(utf8.decode(response.bodyBytes));
+          errorMessage = errorBody['non_field_errors']?[0] ?? 'パスワードが正しくありません。';
+        }
+        Get.snackbar(
+          "エラー",
+          errorMessage,
+          backgroundColor: Colors.red,
+          colorText: Colors.white,
+          snackPosition: SnackPosition.TOP,
+          duration: const Duration(seconds: 3),
+        );
         cats = {};
       }
     } catch( e ){