from inspect import getcallargs

from .schema import User

from .utils import DBDefer

from ..validate import vuserhash, validate

from ..error import UserNotFound, InterfaceException

dbdefer=DBDefer(None)

def setEngine(engine,autocommit=False): 

    dbdefer.engine = engine

    dbdefer.autocommit = autocommit

@dbdefer

@validate(userhash=vuserhash)

def getuser(userhash, session):

    user = session.query(User).filter_by(apikey=userhash).first()

    if user is None:

        raise UserNotFound()

    else:

        return user

def with_user(f):

    def new_f(*args,**kargs):

        kp=getcallargs(f,*args,**kargs)

        try:

            userhash = kp["user"]

        except KeyError:

            raise InterfaceException() 

        def _gotResult(_user):

            kp["user"]=_user

            return f(**kp)

        return getuser(userhash).addCallback(_gotResult)

    new_f.__name__ = f.__name__

    return new_f