bug fixes

main.py

@@ -7,7 +7,9 @@ from pydantic import BaseModel
 from typing import Optional
 from langgraph.graph import StateGraph, END
 from langchain_core.runnables import RunnableLambda
-from langchain.memory import ConversationBufferMemory
+from langchain_core.memory import BaseMemory
+from langchain_core.chat_history import BaseChatMessageHistory
+from langchain_core.messages import HumanMessage, AIMessage
 from langchain_openai import ChatOpenAI
 
 # --- App and Config ---
@@ -19,7 +21,9 @@ OPENAI_API_KEY = os.getenv("OPENAI_API_KEY", "")
 
 # --- OpenAI Client Setup ---
 llm = ChatOpenAI(openai_api_key=OPENAI_API_KEY, model="gpt-4o-mini")
-memory = ConversationBufferMemory(return_messages=True, memory_key="chat_history")
+
+# Simple in-memory chat history (no deprecation warnings)
+chat_history = []
 
 # Initialize LLM only if API key is available
 if not OPENAI_API_KEY:
@@ -28,29 +32,41 @@ if not OPENAI_API_KEY:
 # --- LangGraph Setup ---
 def chat_with_memory(state):
     user_message = state["user_message"]
-    memory.chat_memory.add_user_message(user_message)
-
-    messages = memory.chat_memory.messages[-6:]  # Use last few messages
-    messages = [{"role": msg.type, "content": msg.content} for msg in messages]
-
-    messages.insert(0, {"role": "system", "content": "You are a helpful and concise assistant."})
+    
+    # Add user message to history
+    chat_history.append({"role": "user", "content": user_message})
+    
+    # Keep only last 6 messages for context
+    recent_messages = chat_history[-6:] if len(chat_history) > 6 else chat_history
+    
+    # Add system message at the beginning
+    messages = [{"role": "system", "content": "You are a helpful and concise assistant."}] + recent_messages
 
     try:
         if not OPENAI_API_KEY:
             return {"response": "Sorry, AI chat is not available. Please check your OpenAI API key configuration."}
         
         response = llm.invoke(messages)
-        memory.chat_memory.add_ai_message(response.content)
+        
+        # Add AI response to history
+        chat_history.append({"role": "assistant", "content": response.content})
+        
         return {"response": response.content}
     except Exception as e:
         print(f"Error in chat_with_memory: {e}")
         return {"response": "Sorry, something went wrong: " + str(e)}
 
 # --- Build LangGraph ---
-graph = StateGraph()
+from typing import TypedDict
+
+class ChatState(TypedDict):
+    user_message: str
+    response: str
+
+graph = StateGraph(ChatState)
 graph.add_node("chat", RunnableLambda(chat_with_memory))
 graph.set_entry_point("chat")
-graph.set_finish_point("chat")
+graph.add_edge("chat", END)
 chat_graph = graph.compile()
 
 # --- Webhook Verification ---