Update app.py

app.py

@@ -2,28 +2,28 @@ import streamlit as st
 from dotenv import load_dotenv
 import os
 from langchain_openai import ChatOpenAI
-from langchain.schema import SystemMessage, HumanMessage
+from langchain.schema import SystemMessage, HumanMessage, AIMessage
 from langchain.memory import ConversationBufferMemory
-from langchain.chains import ConversationChain
+from langchain.prompts import ChatPromptTemplate, MessagesPlaceholder
 
-# ✅ Load API keys from environment file
+# ✅ Load environment variables
 load_dotenv("apiroute.env")
 api_key = os.getenv("OPENAI_API_KEY")
 api_base = os.getenv("OPENAI_API_BASE")
 
-# ✅ Initialize the language model
+# ✅ Initialize LLM
 llm = ChatOpenAI(
     model_name="google/gemma-3n-e2b-it:free",
     temperature=0.7
 )
 
-# ✅ Initialize memory
+# ✅ Setup memory
 if "memory" not in st.session_state:
     st.session_state.memory = ConversationBufferMemory(return_messages=True)
 
-# ✅ Inject system prompt only once on app start
-if "intro_done" not in st.session_state:
-    system_message = SystemMessage(
+# ✅ Setup prompt with system message only once
+prompt = ChatPromptTemplate.from_messages([
+    SystemMessage(
         content=(
             "You are Gremmy, a helpful, friendly AI chatbot created by Frederick using Google's Gemma model. "
             "You are smart, polite, and informative.\n"
@@ -31,18 +31,12 @@ if "intro_done" not in st.session_state:
             "- Speak in a concise and helpful tone.\n"
             "- For more information about your creator, visit: https://www.linkedin.com/in/j-frederick-paul-35801a179/"
         )
-    )
-    st.session_state.memory.chat_memory.add_message(system_message)
-    st.session_state.intro_done = True
-
-# ✅ Setup the conversation chain
-chat = ConversationChain(
-    llm=llm,
-    memory=st.session_state.memory,
-    verbose=False
-)
+    ),
+    MessagesPlaceholder(variable_name="chat_history"),
+    HumanMessage(content="{input}")
+])
 
-# ✅ Streamlit page setup
+# ✅ Streamlit UI
 st.set_page_config(page_title="Chatbot", layout="centered")
 st.title("💬 Chat with Gremmy")
 
@@ -54,19 +48,23 @@ if "history" not in st.session_state:
 for sender, msg in st.session_state.history:
     st.markdown(f"**{sender}:** {msg}")
 
-# ✅ Input box and submission form
+# ✅ Input form
 with st.form(key="chat_form", clear_on_submit=True):
     user_input = st.text_input("Talk to me", key="user_message")
     submitted = st.form_submit_button("Send")
 
-# ✅ Handle new message
+# ✅ Generate response
 if submitted and user_input:
-    # Add user message to history
+    # Add to history
     st.session_state.history.append(("You", user_input))
+    st.session_state.memory.chat_memory.add_message(HumanMessage(content=user_input))
 
-    # Get response from the LLM
-    response = chat.run(user_input)
-
-    # Add Gremmy's reply to history
-    st.session_state.history.append(("Gremmy", response.strip()))
+    # Format and run the prompt
+    full_prompt = prompt.format_messages(
+        chat_history=st.session_state.memory.chat_memory.messages,
+        input=user_input
+    )
+    response = llm(full_prompt)
+    st.session_state.history.append(("Gremmy", response.content))
+    st.session_state.memory.chat_memory.add_message(AIMessage(content=response.content))
     st.rerun()