feat: define canonical AI extraction schema with vision-first prompt and add vision priority verification script

verify_vision_priority.py

@@ -0,0 +1,50 @@
+import sys
+import unittest
+
+# Mock modules to avoid ImportError for app dependencies we don't need for this specific test
+from unittest.mock import MagicMock
+sys.modules["sqlalchemy"] = MagicMock()
+sys.modules["sqlalchemy.orm"] = MagicMock()
+sys.modules["app.database"] = MagicMock()
+sys.modules["app.utils.image"] = MagicMock()
+sys.modules["app.utils.text"] = MagicMock()
+sys.modules["app.utils.text"].filter_relevant_text = lambda text, max_length: text
+
+# Mock pydantic
+mock_pydantic = MagicMock()
+class MockBaseModel:
+    pass
+mock_pydantic.BaseModel = MockBaseModel
+mock_pydantic.Field = MagicMock(return_value=None)
+mock_pydantic.field_validator = MagicMock(return_value=lambda x: x)
+sys.modules["pydantic"] = mock_pydantic
+
+# Import the schema module
+from app.ai_schema import get_extraction_prompt
+
+class TestVisionPriorityPrompt(unittest.TestCase):
+    def test_vision_first_directives(self):
+        """Verify that the prompt contains the Vision-First directives."""
+        
+        # Scenario: Some random text context
+        page_text = "Some random text content from the page."
+        prompt = get_extraction_prompt(page_text)
+        
+        print("\nGenerated Prompt Snippet:\n", prompt[:500], "...\n")
+
+        # Check for Critical Directives
+        self.assertIn("Vision-First Price Extraction Agent", prompt)
+        self.assertIn("**SOURCE OF TRUTH = IMAGE**", prompt)
+        self.assertIn("IF IMAGE AND TEXT CONFLICT, TRUST THE IMAGE", prompt)
+        
+        # Check for stock rules
+        self.assertIn("STOCK STATUS RULES", prompt)
+        
+    def test_prompt_without_text(self):
+        """Verify prompt structure when no text is provided."""
+        prompt = get_extraction_prompt(None)
+        self.assertIn("**SOURCE OF TRUTH = IMAGE**", prompt)
+        self.assertNotIn("**Relevant text from page:**", prompt)
+
+if __name__ == "__main__":
+    unittest.main()