import sys
from pathlib import Path

ROOT_DIR = Path(__file__).resolve().parent.parent
if str(ROOT_DIR) not in sys.path:
    sys.path.insert(0, str(ROOT_DIR))

import streamlit as st
import requests

API_URL = "http://0.0.0.0:8000/ask"

st.set_page_config(
    page_title="Lecture RAG",
    layout="wide",
)

st.title("📚 Lecture RAG Assistant")

if "messages" not in st.session_state:
    st.session_state.messages = []

chat_container = st.container()

with chat_container:
    for msg in st.session_state.messages:
        with st.chat_message(msg["role"]):
            st.markdown(msg["content"])

question = st.chat_input("اكتب سؤالك هنا / Ask your question")

if question:
    st.session_state.messages.append({"role": "user", "content": question})
    with chat_container:
        with st.chat_message("user"):
            st.markdown(question)

        with st.chat_message("assistant"):
            with st.spinner("Thinking..."):
                try:
                    response = requests.post(
                        API_URL,
                        json={"question": question},
                        timeout=120
                    )
                    response.raise_for_status()
                    data = response.json()
                    answer = data.get("answer", "No answer returned.")
                except Exception as e:
                    data = {}
                    answer = f"❌ API error: {e}"

                st.markdown(answer)

                if data.get("citations"):
                    with st.expander("📌 Sources"):
                        seen = set()
                        for c in data["citations"].values():
                            key = (c["source"], c["page"])
                            if key not in seen:
                                seen.add(key)
                                st.markdown(f"- 📄 `{c['source']}` | page `{c['page']}`")

    st.session_state.messages.append({"role": "assistant", "content": answer})