app.py

import os
import gradio as gr

# Suppose 'run_with_chain' is your pipeline function from pipeline.py
from pipeline import run_with_chain

# Suppose 'memory' and 'restatement_chain' come from my_memory_logic.py
from my_memory_logic import memory, restatement_chain

def chat_history_fn(user_input, history):
    """
    Rely on LangChain memory to store the entire conversation across calls.
    DO NOT re-add old messages from 'history' each time.
    Also, handle potential None or invalid strings for user_input/answer 
    to avoid Pydantic validation errors.
    """
    # -- 0) Sanitize user_input to ensure it's a valid string
    if not user_input or not isinstance(user_input, str):
        user_input = "" if user_input is None else str(user_input)

    # -- 1) Restate the new user question using existing LangChain memory
    reformulated_q = restatement_chain.run({
        "chat_history": memory.chat_memory.messages,
        "input": user_input
    })

    # -- 2) Pass the reformulated question into your pipeline
    answer = run_with_chain(reformulated_q)
    # also sanitize if needed
    if answer is None or not isinstance(answer, str):
        answer = "" if answer is None else str(answer)

    # -- 3) Add this new user->assistant turn to memory
    memory.chat_memory.add_user_message(user_input)
    memory.chat_memory.add_ai_message(answer)

    # -- 4) Update Gradio’s 'history' so the UI shows the new turn
    history.append((user_input, answer))

    # -- 5) Convert the entire 'history' to message dictionaries:
    #       [{"role":"user","content":...},{"role":"assistant","content":...},...]
    message_dicts = []
    for usr_msg, ai_msg in history:
        if not isinstance(usr_msg, str):
            usr_msg = str(usr_msg) if usr_msg else ""
        if not isinstance(ai_msg, str):
            ai_msg = str(ai_msg) if ai_msg else ""

        message_dicts.append({"role": "user", "content": usr_msg})
        message_dicts.append({"role": "assistant", "content": ai_msg})

    # -- 6) Return the message dictionary list
    return message_dicts

# Build your ChatInterface with the function
demo = gr.ChatInterface(
    fn=chat_history_fn,
    title="DailyWellnessAI with Memory",
    description="A chat bot that remembers context using memory + question restatement."
)

if __name__ == "__main__":
    demo.launch()