import jwt
import uuid
import pam
from secrets import token_hex

from .. import state

def _check_passwd_pam(username: str, passwd: str) -> bool:
    if pam.authenticate(username, passwd):
        return True
    return False

def init_secret():
    secret = token_hex(16)
    state.settings['secret'] = secret

def generate_token(user: str, passwd: str, secret: str) -> dict:
    if user is None or passwd is None:
        return {}
    if _check_passwd_pam(user, passwd):
        app = state.settings['app']
        try:
            users = app.state.vyos_token_users
        except AttributeError:
            app.state.vyos_token_users = {}
            users = app.state.vyos_token_users
        user_id = uuid.uuid1().hex
        payload_data = {'iss': user, 'sub': user_id}
        secret = state.settings.get('secret')
        if secret is None:
            return {
                    "success": False,
                    "errors": ['failed secret generation']
                   }
        token = jwt.encode(payload=payload_data, key=secret, algorithm="HS256")

        users |= {user_id: user}
        return {'token': token}