"""
Tests for the HMAC signed-token registration workflow.

"""

import datetime
import time

from django.conf import settings
from django.core import signing
from django.core.urlresolvers import reverse
from django.http import HttpRequest
from django.test import modify_settings, override_settings

from .. import signals
from registration.backends.hmac.views import REGISTRATION_SALT

from .base import ActivationTestCase


@modify_settings(INSTALLED_APPS={'remove': 'registration'})
@override_settings(ROOT_URLCONF='registration.backends.hmac.urls')
class HMACViewTests(ActivationTestCase):
    """
    Tests for the signed-token registration workflow.

    """
    def test_activation(self):
        """
        Activation of an account functions properly.

        """
        resp = self.client.post(
            reverse('registration_register'),
            data=self.valid_data
        )

        activation_key = signing.dumps(
            obj=self.valid_data[self.user_model.USERNAME_FIELD],
            salt=REGISTRATION_SALT
        )

        with self.assertSignalSent(signals.user_activated):
            resp = self.client.get(
                reverse(
                    'registration_activate',
                    args=(),
                    kwargs={'activation_key': activation_key}
                )
            )

        self.assertRedirects(resp, reverse('registration_activation_complete'))

    def test_repeat_activation(self):
        """
        Once activated, attempting to re-activate an account (even
        with a valid key) does nothing.

        """
        resp = self.client.post(
            reverse('registration_register'),
            data=self.valid_data
        )

        activation_key = signing.dumps(
            obj=self.valid_data[self.user_model.USERNAME_FIELD],
            salt=REGISTRATION_SALT
        )

        with self.assertSignalSent(signals.user_activated):
            resp = self.client.get(
                reverse(
                    'registration_activate',
                    args=(),
                    kwargs={'activation_key': activation_key}
                )
            )
        # First activation redirects to success.
        self.assertRedirects(resp, reverse('registration_activation_complete'))

        with self.assertSignalNotSent(signals.user_activated):
            resp = self.client.get(
                reverse(
                    'registration_activate',
                    args=(),
                    kwargs={'activation_key': activation_key}
                )
            )

        # Second activation fails.
        self.assertEqual(200, resp.status_code)
        self.assertTemplateUsed(resp, 'registration/activate.html')

    # The timestamp calculation will error if USE_TZ=True, due to
    # trying to subtract a naive from an aware datetime. Since time
    # zones aren't relevant to the test, we just temporarily disable
    # time-zone support rather than do the more complex dance of
    # checking the setting and forcing everything to naive or aware.
    @override_settings(USE_TZ=False)
    def test_activation_expired(self):
        """
        An expired account can't be activated.

        """
        self.client.post(
            reverse('registration_register'),
            data=self.valid_data
        )

        # We need to create an activation key valid for the username,
        # but with a timestamp > ACCOUNT_ACTIVATION_DAYS days in the
        # past. This requires monkeypatching time.time() to return
        # that timestamp, since TimestampSigner uses time.time().
        #
        # On Python 3.3+ this is much easier because of the
        # timestamp() method of datetime objects, but since
        # django-registration has to run on Python 2.7, we manually
        # calculate it using a timedelta between the signup date and
        # the UNIX epoch, and patch time.time() temporarily to return
        # a date (ACCOUNT_ACTIVATION_DAYS + 1) days in the past.
        user = self.user_model.objects.get(**self.user_lookup_kwargs)
        joined_timestamp = (
            user.date_joined - datetime.datetime.fromtimestamp(0)
        ).total_seconds()
        expired_timestamp = (
            joined_timestamp - (settings.ACCOUNT_ACTIVATION_DAYS + 1) * 86400
        )
        _old_time = time.time

        try:
            time.time = lambda: expired_timestamp
            activation_key = signing.dumps(
                obj=self.valid_data[self.user_model.USERNAME_FIELD],
                salt=REGISTRATION_SALT
            )
        finally:
            time.time = _old_time

        with self.assertSignalNotSent(signals.user_activated):
            resp = self.client.get(
                reverse(
                    'registration_activate',
                    args=(),
                    kwargs={'activation_key': activation_key}
                )
            )

        self.assertEqual(200, resp.status_code)
        self.assertTemplateUsed(resp, 'registration/activate.html')

    def test_nonexistent_activation(self):
        """
        A nonexistent username in an activation key will fail to
        activate.

        """
        activation_key = signing.dumps(
            obj='parrot',
            salt=REGISTRATION_SALT
        )

        with self.assertSignalNotSent(signals.user_activated):
            resp = self.client.get(
                reverse(
                    'registration_activate',
                    args=(),
                    kwargs={'activation_key': activation_key}
                )
            )

        self.assertEqual(200, resp.status_code)
        self.assertTemplateUsed(resp, 'registration/activate.html')

    def test_activation_signal(self):
        self.client.post(
            reverse('registration_register'),
            data=self.valid_data
        )

        activation_key = signing.dumps(
            obj=self.valid_data[self.user_model.USERNAME_FIELD],
            salt=REGISTRATION_SALT
        )

        with self.assertSignalSent(signals.user_activated,
                                   required_kwargs=['user', 'request']) as cm:
            self.client.get(
                reverse(
                    'registration_activate',
                    args=(),
                    kwargs={'activation_key': activation_key}
                )
            )
            self.assertEqual(
                getattr(cm.received_kwargs['user'],
                        self.user_model.USERNAME_FIELD),
                self.valid_data[self.user_model.USERNAME_FIELD]
            )
            self.assertTrue(
                isinstance(cm.received_kwargs['request'], HttpRequest)
            )