fix: fix various issues before merging

api/tests/test_memoir_image_prompting.py

@@ -1,12 +1,12 @@
 import unittest
-from unittest.mock import Mock
+from unittest.mock import Mock, patch
 
 from api.services.memoir_images.prompting import MemoirImagePromptService
 from api.services.memoir_images.settings import MemoirImageSettings
 
 
 class MemoirImagePromptingTest(unittest.TestCase):
-    def test_prompt_service_uses_category_style_and_plain_fallback_without_llm(self):
+    def test_prompt_service_uses_english_fallback_without_llm(self):
         settings = MemoirImageSettings(
             enabled=True,
             max_per_chapter=2,
@@ -28,7 +28,9 @@ class MemoirImagePromptingTest(unittest.TestCase):
 
         self.assertEqual(result["style"], "watercolor")
         self.assertEqual(result["size"], "1024x1024")
-        self.assertIn("奶奶坐在院子里的藤椅上", result["prompt"])
+        self.assertIn("childhood memory", result["prompt"])
+        self.assertIn("watercolor", result["prompt"])
+        self.assertNotIn("奶奶坐在院子里的藤椅上", result["prompt"])
         self.assertIn("childhood", result["prompt_context"])
 
     def test_prompt_service_parses_structured_llm_response(self):
@@ -59,3 +61,32 @@ class MemoirImagePromptingTest(unittest.TestCase):
         self.assertEqual(result["prompt"], "A grandmother in a quiet courtyard, summer cicadas, soft watercolor")
         self.assertEqual(result["style"], "watercolor")
         self.assertEqual(result["size"], "1024x1024")
+
+    @patch("api.services.memoir_images.prompting.logger")
+    def test_prompt_service_logs_warning_and_falls_back_when_llm_response_is_invalid(
+        self, logger_mock
+    ):
+        settings = MemoirImageSettings(
+            enabled=True,
+            max_per_chapter=2,
+            provider="liblib",
+            default_style="watercolor",
+            default_size="1024x1024",
+            poll_interval_seconds=3,
+            max_attempts=20,
+            liblib_template_uuid="tpl-uuid",
+        )
+        llm = Mock()
+        llm.invoke.return_value.content = "not-json"
+        service = MemoirImagePromptService(llm=llm, settings=settings)
+
+        result = service.build_prompt(
+            chapter_title="童年的夏天",
+            chapter_category="childhood",
+            description="奶奶坐在院子里的藤椅上",
+            context_excerpt="梧桐树下很安静，夏天总有蝉鸣。",
+        )
+
+        self.assertIn("childhood memory", result["prompt"])
+        self.assertNotIn("奶奶坐在院子里的藤椅上", result["prompt"])
+        logger_mock.warning.assert_called_once()