import streamlit as st
from openai import OpenAI
import time
import os
import pandas as pd
import datetime

generated_user = os.getenv("User")
generated_password = os.getenv("Password")
openai_key = os.getenv("openai_key")
assistant_id = os.getenv("ASSISTANT_ID")

st.set_page_config(page_title="Carfind.co.za AI Assistant", layout="wide")
st.markdown("<h1 style='text-align: center;'>🚗 Carfind.co.za AI Assistant</h1>", unsafe_allow_html=True)
st.caption("Chat with Carfind.co.za and find your next car fast")

st.markdown("""
    <style>
    .stChatMessage { max-width: 85%; border-radius: 12px; padding: 8px; }
    .stChatMessage[data-testid="stChatMessage-user"] { background: #f0f0f0; color: #000000; }
    .stChatMessage[data-testid="stChatMessage-assistant"] { background: #D6E9FE; color: #000000; }
    </style>
""", unsafe_allow_html=True)

# Load existing transcript excel or create one
transcript_file = "transcripts.xlsx"

def append_to_transcript(thread_id, role, message):
    timestamp = datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")
    new_entry = {
        "Timestamp": timestamp,
        "Thread_ID": thread_id,
        "Role": role,
        "Message": message
    }

    try:
        if os.path.exists(transcript_file):
            df = pd.read_excel(transcript_file)
            df = pd.concat([df, pd.DataFrame([new_entry])], ignore_index=True)
        else:
            df = pd.DataFrame([new_entry])

        df.to_excel(transcript_file, index=False)
    except Exception as e:
        st.error(f"Failed to log conversation: {str(e)}")

if "authenticated" not in st.session_state:
    st.session_state.authenticated = False

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.")

else:
    st.divider()

    if "thread_id" not in st.session_state:
        st.session_state["thread_id"] = None

    input_col, clear_col = st.columns([8, 1])
    with input_col:
        user_input = st.text_input("Type your message here...", key="chat_input")

    with clear_col:
        if st.button("🗑️", help="Clear Chat"):
            st.session_state["thread_id"] = None
            st.success("Chat cleared.")
            st.rerun()

    if openai_key and assistant_id:
        client = OpenAI(api_key=openai_key)

        if user_input:
            if not st.session_state["thread_id"]:
                thread = client.beta.threads.create()
                st.session_state["thread_id"] = thread.id

            client.beta.threads.messages.create(
                thread_id=st.session_state["thread_id"], role="user", content=user_input
            )
            append_to_transcript(st.session_state["thread_id"], "User", user_input)

            try:
                with st.spinner("Thinking and typing... 💭"):
                    run = client.beta.threads.runs.create(
                        thread_id=st.session_state["thread_id"], assistant_id=assistant_id
                    )

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

                messages_response = client.beta.threads.messages.list(
                    thread_id=st.session_state["thread_id"]
                )

                assistant_icon_html = "<img src='https://www.carfind.co.za/images/Carfind-Icon.svg' width='22' style='vertical-align:middle;'/>"

                for msg in reversed(messages_response.data):
                    content = msg.content[0].text.value
                    if msg.role == "user":
                        st.markdown(
                            f"<div style='background-color:#f0f0f0; color:#000000; padding:10px; border-radius:8px; margin:5px 0;'>"
                            f"👤 <strong>You:</strong> {content}"
                            f"</div>", 
                            unsafe_allow_html=True
                        )
                    else:
                        st.markdown(
                            f"<div style='background-color:#D6E9FE; color:#000000; padding:10px; border-radius:8px; margin:5px 0;'>"
                            f"{assistant_icon_html} <strong>Carfind Assistant:</strong> {content}"
                            f"</div>", 
                            unsafe_allow_html=True
                        )
                        append_to_transcript(st.session_state["thread_id"], "Assistant", content)

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

    else:
        st.error("⚠️ OpenAI key or Assistant ID not found. Please ensure both are set as Hugging Face secrets.")