import streamlit as st
import os
import time
import re
import requests
from PIL import Image
from io import BytesIO
from urllib.parse import quote
from openai import OpenAI

# ------------------ Authentication ------------------
VALID_USERS = {
    "andrew@lortechnologies.com": "Pass.123",
    "asherS@schlagergroup.com.au": "Pass.123",
    "daniel@schlagergroup.com.au": "Pass.123",
    "admin@schlagergroup.com.au": "Pass.123",
}

def login():
    st.title("🔐 Login Required")
    email = st.text_input("Email")
    password = st.text_input("Password", type="password")
    if st.button("Login"):
        if VALID_USERS.get(email) == password:
            st.session_state.authenticated = True
            st.rerun()
        else:
            st.error("❌ Incorrect email or password.")

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

if not st.session_state.authenticated:
    login()
    st.stop()

# ------------------ App Configuration ------------------
st.set_page_config(page_title="AI Pathology Assistant", layout="wide", initial_sidebar_state="collapsed")
st.title("🧬 AI Pathology Assistant")
st.caption("AI-powered exploration of pathology, anatomy, and histology documents via OCR + GPT")

# ------------------ Load OpenAI API Key ------------------
OPENAI_API_KEY = os.environ.get("OPENAI_API_KEY")
if not OPENAI_API_KEY:
    st.error("❌ Missing OPENAI_API_KEY environment variable.")
    st.stop()

client = OpenAI(api_key=OPENAI_API_KEY)

# ------------------ Assistant Configuration ------------------
ASSISTANT_ID = "asst_jXDSjCG8LI4HEaFEcjFVq8KB"  # Replace with your Assistant ID

# ------------------ Session State ------------------
if "messages" not in st.session_state:
    st.session_state.messages = []
if "thread_id" not in st.session_state:
    st.session_state.thread_id = None
if "image_urls" not in st.session_state:
    st.session_state.image_urls = []
if "pending_prompt" not in st.session_state:
    st.session_state.pending_prompt = None

# ------------------ Sidebar ------------------
with st.sidebar:
    st.header("🧪 Pathology Tools")
    if st.button("🧹 Clear Chat"):
        st.session_state.messages = []
        st.session_state.thread_id = None
        st.session_state.image_urls = []
        st.session_state.pending_prompt = None
        st.rerun()

    show_image = st.toggle("📸 Show Slide Images", value=True)
    keyword = st.text_input("Keyword Search", placeholder="e.g. mitosis, carcinoma")
    if st.button("🔎 Search") and keyword:
        st.session_state.pending_prompt = f"Find clauses or references related to: {keyword}"

    section = st.text_input("Section Lookup", placeholder="e.g. Connective Tissue")
    if section:
        st.session_state.pending_prompt = f"Summarize or list key points from section: {section}"

    actions = [
        "Select an action...",
        "List histological features of inflammation",
        "Summarize features of carcinoma",
        "List muscle types and features",
        "Extract diagnostic markers",
        "Summarize embryology stages"
    ]
    action = st.selectbox("Common Pathology Queries", actions)
    if action != actions[0]:
        st.session_state.pending_prompt = action

# ------------------ Main Chat UI ------------------
chat_col, image_col = st.columns([2, 1])

with chat_col:
    st.markdown("### 💬 Ask a Pathology-Specific Question")
    user_input = st.chat_input("Example: What are features of squamous cell carcinoma?")
    if user_input:
        st.session_state.messages.append({"role": "user", "content": user_input})
    elif st.session_state.pending_prompt:
        st.session_state.messages.append({"role": "user", "content": st.session_state.pending_prompt})
        st.session_state.pending_prompt = None

    if st.session_state.messages and st.session_state.messages[-1]["role"] == "user":
        try:
            if st.session_state.thread_id is None:
                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=st.session_state.messages[-1]["content"]
            )

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

            with st.spinner("🔬 Analyzing..."):
                while True:
                    status = client.beta.threads.runs.retrieve(thread_id=st.session_state.thread_id, run_id=run.id)
                    if status.status in ("completed", "failed", "cancelled"):
                        break
                    time.sleep(1)

            if status.status == "completed":
                messages = client.beta.threads.messages.list(thread_id=st.session_state.thread_id)
                for m in reversed(messages.data):
                    if m.role == "assistant":
                        reply = m.content[0].text.value
                        st.session_state.messages.append({"role": "assistant", "content": reply})

                        # 🔍 Extract all GitHub image URLs
                        image_matches = re.findall(
                            r'https://raw\.githubusercontent\.com/AndrewLORTech/witspathologai/main/[^\s\n]+\.png',
                            reply
                        )
                        st.session_state.image_urls = image_matches
                        break
            else:
                st.error("❌ Assistant failed to respond.")
            st.rerun()
        except Exception as e:
            st.error(f"❌ Error: {e}")

    for msg in st.session_state.messages:
        with st.chat_message(msg["role"]):
            st.markdown(msg["content"], unsafe_allow_html=True)

# ------------------ Image Preview with Safe Encoding ------------------
with image_col:
    if show_image and st.session_state.image_urls:
        st.markdown("### 🖼️ Slide Previews")
        for raw_url in st.session_state.image_urls:
            try:
                url_parts = raw_url.split("githubusercontent.com/")
                if len(url_parts) == 2:
                    encoded_path = quote(url_parts[1])
                    encoded_url = f"https://raw.githubusercontent.com/{encoded_path}"
                else:
                    encoded_url = raw_url

                r = requests.get(encoded_url)
                r.raise_for_status()
                img = Image.open(BytesIO(r.content))
                st.image(img, caption=f"📷 {encoded_url.split('/')[-1]}", use_container_width=True)
            except Exception as e:
                st.error(f"❌ Failed to load image from {raw_url}: {e}")