# file: chatbot_rulebased.py
import re
import random

RESPONSES = {
    "greeting": ["Hey!", "Hi there!", "Hello! How can I help?"],
    "bye": ["Goodbye!", "See ya!", "Take care!"],
    "thanks": ["You’re welcome!", "No problem!", "Anytime!"],
    "default": [
        "Sorry — I don't understand. Can you say that differently?",
        "Hmm, tell me more.",
    ],
}

KEYWORDS = {
    "greeting": ["hello", "hi", "hey", "yo"],
    "bye": ["bye", "goodbye", "see you", "later"],
    "thanks": ["thanks", "thank you", "thx"],
}

def classify(message: str):
    m = message.lower()
    for intent, keys in KEYWORDS.items():
        for k in keys:
            if re.search(r"\b" + re.escape(k) + r"\b", m):
                return intent
    return "default"

def respond(message: str, user_state: dict):
    intent = classify(message)
    if intent == "greeting":
        return random.choice(RESPONSES["greeting"])
    if intent == "bye":
        return random.choice(RESPONSES["bye"])
    if intent == "thanks":
        return random.choice(RESPONSES["thanks"])
    # simple small-talk memory example:
    if "name is" in message.lower():
        name = message.split("name is")[-1].strip().split()[0].capitalize()
        user_state["name"] = name
        return f"Nice to meet you, {name}!"
    if "what is my name" in message.lower() or "do you remember my name" in message.lower():
        return f"I think your name is {user_state.get('name', 'not set yet — tell me!')}"
    return random.choice(RESPONSES["default"])

def main():
    print("Chatbot (type 'quit' to exit)\n")
    state = {}
    while True:
        user = input("You: ").strip()
        if not user:
            continue
        if user.lower() in ("quit", "exit"):
            print("Bot:", random.choice(RESPONSES["bye"]))
            break
        print("Bot:", respond(user, state))

if __name__ == "__main__":
    main()