# -*- coding: UTF-8 -*-

# django dependencies
from django.contrib.auth.views import redirect_to_login
from django.contrib.auth import REDIRECT_FIELD_NAME
from django.conf import settings

# python dependencies
from re import compile

#---#

EXEMPT_URLS = [compile(settings.LOGIN_URL.lstrip('/'))]
if hasattr(settings, 'LOGIN_EXEMPT_URLS'):
    EXEMPT_URLS += [compile(expr) for expr in settings.LOGIN_EXEMPT_URLS]

#---#

class LoginRequiredMiddleware:
    """
    Middleware that requires a user to be authenticated to view any page other
    than LOGIN_URL. Exemptions to this requirement can optionally be specified
    in settings via a list of regular expressions in LOGIN_EXEMPT_URLS (which
    you can copy from your urls.py).

    Requires authentication middleware and template context processors to be
    loaded. You'll get an error if they aren't.
    """
    def process_request(self, request):
        assert hasattr(request, 'user'), "The Login Required middleware\
         requires authentication middleware to be installed. Edit your\
         MIDDLEWARE_CLASSES setting to insert\
         'django.contrib.auth.middlware.AuthenticationMiddleware'. If that doesn't\
         work, ensure your TEMPLATE_CONTEXT_PROCESSORS setting includes\
         'django.core.context_processors.auth'."
        if not request.user.is_authenticated():
            path = request.path_info.lstrip('/')
            if not any(m.match(path) for m in EXEMPT_URLS):            
                path = request.get_full_path()
                return redirect_to_login(path, settings.LOGIN_URL, REDIRECT_FIELD_NAME)

            
#---#