from django.core.exceptions import ImproperlyConfigured
from django.http import HttpResponseRedirect

from django.contrib.auth.decorators import login_required
from django.contrib.auth import REDIRECT_FIELD_NAME

from . import app_settings, utils, adapter

@login_required
def ltpa(request):
    '''Ask for authentication then generate a cookie'''
    next_url = request.REQUEST[REDIRECT_FIELD_NAME]
    response = HttpResponseRedirect(next_url)
    if app_settings.TOKEN_SECRET is None:
        raise ImproperlyConfigured('missing TOKEN_SECRET')
    secret = utils.decode_secret(app_settings.TOKEN_SECRET)
    user = adapter.get_adapter().get_username(request)
    token = utils.generate_domino_ltpa_token(user, secret, duration=app_settings.TOKEN_DURATION)
    domain = app_settings.COOKIE_DOMAIN or request.META['HTTP_HOST'].split(':')[0]
    response.set_cookie(app_settings.COOKIE_NAME, token, domain=domain,
            httponly=app_settings.COOKIE_HTTP_ONLY)
    return response