from djangorestframework.authentication import BaseAuthentication
from .models import Token

class TokenAuthentication(BaseAuthentication):
    """
    Use a token model for authentication.

    A custom token model may be used here, but must have the following minimum
    properties:

    * key -- The string identifying the token
    * user -- The user to which the token belongs
    * revoked -- The status of the token

    The BaseToken class is available as an abstract model to be derived from.

    The token key should be passed in as a string to the "Authorization" HTTP
    header.
    """
    model = Token

    def authenticate(self, request):
        key = request.META.get('HTTP_AUTHORIZATION', '').strip()
        if not key:
            return None

        try:
             token = self.model.objects.get(key=key)
        except self.model.DoesNotExist:
             return None

        if token.user.is_active and not token.revoked:
            return (token.user, token)