app.py

import streamlit as st
from nlp_utils import load_intents, get_intent, get_response
from langchain_groq import ChatGroq
import os
from dotenv import load_dotenv
import re

# -------------------- PAGE CONFIG --------------------
st.set_page_config(page_title="Foodie Hub Chatbot", page_icon="🍔", layout="centered")

# -------------------- DARK THEME --------------------
st.markdown("""
<style>
.stApp { background-color: #000000; color: white; }

.menu-card {
    background: linear-gradient(145deg,#0a0a0a,#000);
    border: 1px solid #ff1a1a;
    padding: 14px;
    border-radius: 12px;
    box-shadow: 0 0 10px #ff0000;
    text-align: center;
    margin-bottom: 10px;
}

.price-tag { color: #00ffcc; font-weight: bold; font-size: 18px; }

.category-title {
    color: #ff4d4d;
    font-size: 22px;
    margin-top: 20px;
    text-shadow: 0 0 8px #ff0000;
}
</style>
""", unsafe_allow_html=True)

# -------------------- LOAD ENV + LLM --------------------
load_dotenv()

llm = ChatGroq(
    groq_api_key=os.getenv("GROQ_API_KEY"),
    model_name="openai/gpt-oss-120b"
)

# -------------------- LOAD INTENTS --------------------
intents = load_intents()

# -------------------- MENU --------------------
menu = {
    "Margherita Pizza": 199,
    "Farmhouse Pizza": 249,
    "Paneer Tikka Pizza": 269,
    "Veg Burger": 99,
    "Cheese Burger": 129,
    "Double Patty Burger": 159,
    "White Sauce Pasta": 179,
    "Red Sauce Pasta": 169,
    "Coke": 49,
    "Pepsi": 49,
    "Sprite": 49
}

# -------------------- KEYWORDS --------------------
item_keywords = {
    "margherita": "Margherita Pizza",
    "farmhouse": "Farmhouse Pizza",
    "paneer": "Paneer Tikka Pizza",
    "veg burger": "Veg Burger",
    "cheese burger": "Cheese Burger",
    "double patty": "Double Patty Burger",
    "double burger": "Double Patty Burger",
    "white sauce": "White Sauce Pasta",
    "white pasta": "White Sauce Pasta",
    "red sauce": "Red Sauce Pasta",
    "red pasta": "Red Sauce Pasta",
    "coke": "Coke",
    "pepsi": "Pepsi",
    "sprite": "Sprite"
}

categories = {
    "pizza": ["Margherita Pizza", "Farmhouse Pizza", "Paneer Tikka Pizza"],
    "burger": ["Veg Burger", "Cheese Burger", "Double Patty Burger"],
    "pasta": ["White Sauce Pasta", "Red Sauce Pasta"],
    "cold drink": ["Coke", "Pepsi", "Sprite"]
}

# -------------------- SESSION STATE --------------------
if "messages" not in st.session_state:
    st.session_state.messages = []

if "cart" not in st.session_state:
    st.session_state.cart = {}

if "pending_category" not in st.session_state:
    st.session_state.pending_category = None

if "pending_qty" not in st.session_state:
    st.session_state.pending_qty = 0

# -------------------- TITLE --------------------
st.markdown("""
<div style="text-align:center; border:1px solid #ff1a1a; padding:18px; border-radius:12px;
box-shadow:0 0 14px #ff0000;">
<h1 style="color:#ff1a1a; -webkit-text-stroke:1px white;
text-shadow:0 0 6px #ff0000,0 0 18px #ff0000;">FOODIE HUB</h1>
<p style="color:white; text-shadow:0 0 6px #ff0000;">The Ultimate Snack Haven</p>
</div>
""", unsafe_allow_html=True)

# -------------------- CLEAR CHAT BUTTON --------------------
col1, col2 = st.columns([8, 2])
with col2:
    if st.button("🗑️ Clear Chat"):
        st.session_state.messages = []
        st.session_state.cart = {}
        st.session_state.pending_category = None
        st.session_state.pending_qty = 0
        st.rerun()

# -------------------- MENU UI --------------------
def show_menu():
    for category, items in categories.items():
        category_display = category.upper() + "S"
        st.markdown(f'<div class="category-title">{category_display}</div>', unsafe_allow_html=True)
        for item in items:
            col1, col2 = st.columns([3, 1])
            with col1:
                st.write(f"**{item}**")
            with col2:
                st.write(f"₹{menu[item]}")
        st.divider()

# -------------------- DISPLAY CHAT --------------------
for msg in st.session_state.messages:
    st.chat_message(msg["role"]).write(msg["content"])

# -------------------- SIDEBAR MENU --------------------
with st.sidebar:
    st.markdown('<div class="category-title">📋 MENU</div>', unsafe_allow_html=True)
    show_menu()

# -------------------- LLM --------------------
def ask_llm(question):
    response = llm.invoke(question)
    return response.content

# -------------------- PARSER --------------------
def extract_items(text):
    items = []
    
    # Split by "and" to handle multiple commands
    parts = re.split(r'\band\b', text, flags=re.IGNORECASE)
    
    for part in parts:
        matches = re.findall(r"(add|remove|delete)?\s*(\d+)?\s*([a-zA-Z ]+)", part)

        for action, qty, name in matches:
            qty = int(qty) if qty else 1
            name = name.strip().lower()
            
            # Remove articles (a, an, the)
            name = re.sub(r'\b(a|an|the)\b\s*', '', name).strip()

            # ITEM MATCH (Higher Priority)
            item_matched = False
            for keyword, item_name in item_keywords.items():
                # Handle plurals by checking both singular and removing trailing 's'
                if keyword in name or (name.endswith('s') and keyword in name[:-1]):
                    items.append((action, item_name, qty, "item"))
                    item_matched = True
                    break

            # CATEGORY MATCH (Only if no item matched)
            if not item_matched:
                for category in categories:
                    # Handle plurals for categories too
                    if category in name or (name.endswith('s') and category in name[:-1]):
                        items.append((action, category, qty, "category"))
                        break

    return items

# -------------------- USER INPUT --------------------
user_input = st.chat_input("Order food, view cart, checkout...")

if user_input:
    st.chat_message("user").write(user_input)
    user_text = user_input.lower()

    responses = []

    # ---------- HANDLE PENDING CATEGORY SELECTION ----------
    if st.session_state.pending_category:
        category = st.session_state.pending_category
        qty = st.session_state.pending_qty

        for item in categories[category]:
            if item.lower() in user_text:
                st.session_state.cart[item] = st.session_state.cart.get(item, 0) + qty
                responses.append(f"✅ Added {item} x{qty}")

                st.session_state.pending_category = None
                st.session_state.pending_qty = 0
                break

    # ---------- SHOW MENU ----------
    elif "menu" in user_text:
        responses.append("Check the menu in the sidebar! ")

    # ---------- CLEAR CART ----------
    elif "clear cart" in user_text or "empty cart" in user_text:
        st.session_state.cart = {}
        responses.append("🧹 Cart cleared.")

    # ---------- VIEW CART ----------
    elif "cart" in user_text and "add" not in user_text:
        if not st.session_state.cart:
            responses.append("🛒 Your cart is empty.")
        else:
            total = sum(menu[item] * qty for item, qty in st.session_state.cart.items())
            cart_items = "\n".join(f"• {item} x{qty} – ₹{menu[item]*qty}" for item, qty in st.session_state.cart.items())
            responses.append(f"🛒 **Your Cart:**\n{cart_items}\n\n💰 **Total: ₹{total}**")

    # ---------- CHECKOUT ----------
    elif "checkout" in user_text or "place order" in user_text or "bill" in user_text:
        if not st.session_state.cart:
            responses.append("🛒 Your cart is empty.")
        else:
            total = sum(menu[item] * qty for item, qty in st.session_state.cart.items())
            responses.append(f"💳 Order placed successfully!\nTotal bill: ₹{total}\nThank you for ordering from Foodie Hub! 🍔")
            st.session_state.cart = {}

    else:
        parsed_items = extract_items(user_text)

        if parsed_items:
            for action, name, qty, typ in parsed_items:

                # -------- REMOVE --------
                if action in ["remove", "delete"]:

                    if typ == "item":
                        if name in st.session_state.cart:
                            available = st.session_state.cart[name]
                            if available >= qty:
                                st.session_state.cart[name] -= qty
                                if st.session_state.cart[name] <= 0:
                                    del st.session_state.cart[name]
                                responses.append(f"❌ Removed {name} x{qty}")
                            else:
                                responses.append(f"⚠️ You only have {available} {name}(s) in cart, removing all {available}")
                                del st.session_state.cart[name]
                        else:
                            responses.append(f"⚠️ {name} not in cart")

                    elif typ == "category":
                        qty_to_remove = qty
                        removed_count = 0
                        for item in categories[name]:
                            if item in st.session_state.cart and qty_to_remove > 0:
                                available = st.session_state.cart[item]

                                if available <= qty_to_remove:
                                    qty_to_remove -= available
                                    del st.session_state.cart[item]
                                    responses.append(f"❌ Removed {item} x{available}")
                                    removed_count += available
                                else:
                                    st.session_state.cart[item] -= qty_to_remove
                                    responses.append(f"❌ Removed {item} x{qty_to_remove}")
                                    removed_count += qty_to_remove
                                    qty_to_remove = 0

                        if qty_to_remove > 0:
                            responses.append(f"⚠️ Only removed {removed_count} {name}s (not enough available)")

                # -------- ADD --------
                else:
                    if typ == "item":
                        st.session_state.cart[name] = st.session_state.cart.get(name, 0) + qty
                        responses.append(f"✅ Added {name} x{qty}")

                    elif typ == "category":
                        st.session_state.pending_category = name
                        st.session_state.pending_qty = qty
                        responses.append(
                            f"Which {name} would you like? {', '.join(categories[name])}"
                        )

        else:
            intent, score = get_intent(user_input, intents)

            if score > 0.5:
                responses.append(get_response(intent, intents))
            else:
                responses.append(ask_llm(user_input))

    bot_response = "\n".join(responses)
    st.chat_message("assistant").write(bot_response)

    st.session_state.messages.append({"role": "user", "content": user_input})
    st.session_state.messages.append({"role": "assistant", "content": bot_response})