from django.http import HttpResponseRedirect
from django.conf import settings

import re


class LoginRequiredMiddleware:
    """
    If user is not accessing the site from an authorized IP, force
    authentification.
    """
    def __init__(self, get_response):
        """Init middleware"""
        self.get_response = get_response
        self.whitelist_re = re.compile("^/accounts/.*$")

    def __call__(self, request):
        """
        If user is not authenticated and external, redirect to login view
        before calling the view.
        """
        if not request.user.is_authenticated:
            if not self.whitelist_re.match(request.path_info):
                return HttpResponseRedirect(settings.LOGIN_URL)

        response = self.get_response(request)
        return response