Update src/rag_engine.py

src/rag_engine.py

@@ -7,7 +7,7 @@ from langchain_core.output_parsers import StrOutputParser
 from langchain_core.runnables import RunnablePassthrough, RunnableParallel
 from langchain_community.embeddings import HuggingFaceEmbeddings
 from langchain_openai import ChatOpenAI
-
+from langchain_community.chat_models import ChatLiteLLM
 
 class ProjectRAGEngine:
     def __init__(self):
@@ -17,26 +17,12 @@ class ProjectRAGEngine:
             model_kwargs={"device": "cpu"},   # change to "cuda" if GPU available
             encode_kwargs={"normalize_embeddings": True}
         )
-
         # ✅ OpenRouter LLM (Chat only)
-        self.llm = ChatOpenAI(
-        model="openai/gpt-oss-120b:free",
-        temperature=0,
-    
-        # ✅ CORRECT PARAM
-        api_key=os.getenv("OPENROUTER_API_KEY"),
-    
-        # ✅ OpenRouter endpoint
-        base_url="https://openrouter.ai/api/v1",
-    
-        # ✅ REQUIRED HEADERS FOR OPENROUTER
-        default_headers={
-            "Authorization": f"Bearer {os.getenv('OPENROUTER_API_KEY')}",
-            "HTTP-Referer": "http://localhost:8501",
-            "X-Title": "Project-RAG-App"
-        })
-
-
+        self.llm = ChatLiteLLM(
+            model="openrouter/openai/gpt-oss-120b:free",
+            api_key=os.getenv("OPENROUTER_API_KEY"),
+            temperature=0
+        )
         self.vector_store = None
 
     def process_documents(self, pdf_paths):