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

# Get environment variables
openai_key = os.getenv("openai_key")
assistant_id = os.getenv("ASSISTANT_ID")

# Load or create transcript file
transcript_file = "transcripts.xlsx"
if not os.path.exists(transcript_file):
    df = pd.DataFrame(columns=["timestamp", "thread_id", "role", "message"])
    df.to_excel(transcript_file, index=False)

# Function to append to transcript
def append_to_transcript(thread_id, role, message):
    df_existing = pd.read_excel(transcript_file)
    new_entry = pd.DataFrame({
        "timestamp": [datetime.now().strftime("%Y-%m-%d %H:%M:%S")],
        "thread_id": [thread_id],
        "role": [role],
        "message": [message]
    })
    updated_df = pd.concat([df_existing, new_entry], ignore_index=True)
    updated_df.to_excel(transcript_file, index=False)

# Streamlit UI setup
st.set_page_config(page_title="Carfind.co.za AI Assistant", layout="wide")

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)

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

        # Add user message
        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)

            # Get full conversation
            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;'/>"

            # Display newest-first
            messages_sorted = sorted(messages_response.data, key=lambda x: x.created_at, reverse=True)
            for msg in messages_sorted:
                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> {msg.content[0].text.value}"
                        f"</div>", 
                        unsafe_allow_html=True
                    )
                else:
                    response_text = msg.content[0].text.value
                    append_to_transcript(st.session_state["thread_id"], "assistant", response_text)
                    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> {response_text}"
                        f"</div>", 
                        unsafe_allow_html=True
                    )

            # Scroll to top automatically
            st.markdown("""
                <script>
                    window.scrollTo(0, 0);
                </script>
            """, unsafe_allow_html=True)

        except Exception as e:
            st.error(f"An error occurred: {str(e)}")
else:
    st.error("⚠️ OpenAI key or Assistant ID not found