from mongoengine import *
from datetime import datetime

MONGODB_URI="mongodb+srv://brijrvl:igbot567@orderbot.obb7gan.mongodb.net/?retryWrites=true&w=majority&appName=orderbot"
DATABASE_NAME="analyticsbot"

connect(
    db=DATABASE_NAME,
    host=MONGODB_URI,
)

class ChatManager:
    def __init__(self):
        self.connect_to_db()

    def connect_to_db(self):
        # Connection to MongoDB
        connect(db=DATABASE_NAME, host=MONGODB_URI)

    class Session(Document):
        phone_number_id = StringField(required=True, unique=True)
        chat_history = StringField(default="")
        meta = {
            'collection': 'sessions',
            'db_alias': 'default'
        }

    class Message(Document):
        session_id = ReferenceField('ChatManager.Session', required=True)
        phone_number_id = StringField(required=True)
        role = StringField(choices=['USER', 'ASSISTANT'], required=True)
        content = StringField(required=True)
        timestamp = DateTimeField(default=datetime.utcnow, required=True)
        meta = {
            'collection': 'messages',
            'db_alias': 'default'
        }

    def get_or_create_session(self, phone_number):
        session = self.Session.objects(phone_number_id=phone_number).first()
        if not session:
            session = self.Session(phone_number_id=phone_number).save()
        return session

    def save_message(self, session_id, phone_number, role, content):
        print("Here 3")
        message = self.Message(
            session_id=session_id,
            phone_number_id=phone_number,
            role=role,
            content=content,
            timestamp=datetime.utcnow()
        )
        message.save()
        print("Here 4")
        return message

    def get_last_n_messages(self, session, n=10):
        # Retrieve the last `n` messages for the given session
        messages = self.Message.objects(session_id=session.id).order_by('-timestamp')[:n]
        return messages

    def build_chat_history(self, messages):
        # Build chat history string from the retrieved messages
        chat_history = []
        for message in messages:
            chat_history.append(f"{message.role}: {message.content}")
        return "\n".join(reversed(chat_history))

    def handle_message(self, phone_number, content):
        session = self.get_or_create_session(phone_number)

        self.save_message(session.id, phone_number, 'USER', content)

        last_messages = self.get_last_n_messages(session)

        if len(last_messages) >= 10:
            last_three_messages = last_messages[:10]
        else:
            last_three_messages = last_messages

        str_chat_history = self.build_chat_history(last_three_messages)

        return str_chat_history