app/policy.py

# app/policy.py
from __future__ import annotations
import os, re

# --- Topic detection (very lightweight, fast) ---
CAFE_KEYWORDS = [
    "menu","order","item","dish","pizza","burger","salad","pasta","vegan","gluten",
    "price","special","deal","offer","hours","open","close","time","location","address",
    "book","reserve","reservation","table","party","pickup","delivery","takeout","payment",
    "futurecafe","future cafe","future-cafe","café","coffee","drinks","beverage","side"
]
_kw_re = re.compile(r"|".join([re.escape(k) for k in CAFE_KEYWORDS]), re.I)

SMALLTALK = r"\b(hi|hello|hey|good\s+(morning|afternoon|evening)|thanks|thank you|bye|goodbye)\b"
_smalltalk_re = re.compile(SMALLTALK, re.I)

def is_cafe_topic(text: str) -> bool:
    return bool(text and _kw_re.search(text))

def is_smalltalk(text: str) -> bool:
    return bool(text and _smalltalk_re.search(text))

def unrelated_limit() -> int:
    """How many off-topic turns allowed before ending."""
    try:
        n = int(os.getenv("CAFE_UNRELATED_LIMIT", "3"))
        return max(1, min(5, n))
    except Exception:
        return 3

# --- Messages ---
POLITE_REFUSAL = (
    "I’m here to help with FutureCafe—menu, hours, reservations, and orders. "
    "Could you ask something about the restaurant?"
)

POLITE_REFUSAL_2 = (
    "To keep things focused, I can only help with FutureCafe. "
    "Ask me about our menu, hours, or booking a table."
)

def end_message() -> str:
    return ("I’m only able to help with FutureCafe topics. "
            "Let’s end this chat for now. If you need menu, hours, or reservations, "
            "message me again anytime.")