import streamlit as st
from streamlit_chat import message
from openai import OpenAI
import time
import datetime
import os

# Securely get credentials
generated_user = os.getenv("User")
generated_password = os.getenv("Password")
openai_key = os.getenv("openai_key")

# Streamlit page config
st.set_page_config(page_title="Carfind.co.za AI Assistant", layout="wide")
st.title("🚗 Carfind.co.za AI Assistant")
st.caption("Chat with Carfind.co.za and find your next car fast")

# Theme toggle
if "theme" not in st.session_state:
    st.session_state.theme = "dark"

toggle = st.toggle("Switch to Light Mode")
if toggle:
    st.session_state.theme = "light"
else:
    st.session_state.theme = "dark"

if st.session_state.theme == "light":
    st.markdown(
        """
        <style>
        body { background-color: #f0f0f0; color: #000; }
        </style>
        """,
        unsafe_allow_html=True
    )
else:
    st.markdown(
        """
        <style>
        body { background-color: #0e0e0e; color: #fff; }
        </style>
        """,
        unsafe_allow_html=True
    )

# Initialize authentication state
if "authenticated" not in st.session_state:
    st.session_state.authenticated = False

# Login screen
if not st.session_state.authenticated:
    st.subheader("🔐 Login")
    username = st.text_input("Username")
    password = st.text_input("Password", type="password")

    if username and password:
        if username == generated_user and password == generated_password:
            st.session_state.authenticated = True
            st.success("Login successful! Redirecting...")
            time.sleep(1)
            st.rerun()
        else:
            st.error("Incorrect username or password. Please try again.")

# Main chat UI using streamlit-chat
else:
    if "messages" not in st.session_state:
        st.session_state["messages"] = []

    st.divider()

    # Display chat history with avatars
    for i, msg in enumerate(st.session_state["messages"]):
        avatar_url = "https://www.carfind.co.za/images/Carfind-Icon.svg" if msg["role"] == "assistant" else None
        message(
            msg["content"],
            is_user=(msg["role"] == "user"),
            key=str(i),
            avatar_style="adventurer" if msg["role"] == "user" else None,
            seed="user-seed" if msg["role"] == "user" else None,
            avatar_url=avatar_url
        )

    col_input, col_clear = st.columns([10, 1])

    with col_input:
        user_input = st.text_input("Type your message here:", key="input")

    with col_clear:
        if st.button("🗑️", help="Clear chat"):
            st.session_state.messages = []
            st.rerun()

    # Handle OpenAI assistant (with loop protection)
    if user_input and openai_key:
        # Avoid duplicate messages triggering loops
        if len(st.session_state.messages) == 0 or user_input != st.session_state.messages[-1]["content"]:
            st.session_state.messages.append({"role": "user", "content": user_input})

            with st.spinner("Thinking and typing... 💬"):
                client = OpenAI(api_key=openai_key)
                ASSISTANT_ID = "asst_5gQR21fOsmHil11FGBzEArA7"

                def save_transcript(messages):
                    with open("chat_logs.txt", "a") as log:
                        log.write(f"\n--- New Chat ({datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')}) ---\n")
                        for msg in messages:
                            log.write(f"{msg['role'].capitalize()}: {msg['content']}\n")
                        log.write("--- End Chat ---\n")

                try:
                    thread = client.beta.threads.create()
                    thread_id = thread.id

                    client.beta.threads.messages.create(
                        thread_id=thread_id,
                        role="user",
                        content=user_input
                    )

                    run = client.beta.threads.runs.create(
                        thread_id=thread_id,
                        assistant_id=ASSISTANT_ID
                    )

                    while True:
                        run_status = client.beta.threads.runs.retrieve(
                            thread_id=thread_id,
                            run_id=run.id
                        )
                        if run_status.status == "completed":
                            break
                        time.sleep(1)

                    messages_response = client.beta.threads.messages.list(thread_id=thread_id)
                    assistant_reply = messages_response.data[0].content[0].text.value

                    # Prevent infinite repetition by ignoring if assistant echoes input
                    if assistant_reply.strip().lower() != user_input.strip().lower():
                        st.session_state.messages.append({"role": "assistant", "content": assistant_reply})
                        save_transcript(st.session_state.messages)

                    st.rerun()

                except Exception as e:
                    st.error(f"An error occurred: {str(e)}")

    elif not openai_key:
        st.error("OpenAI key not found. Please ensure it is set as a Hugging Face secret.")