import random
import string
import time

from mock import patch

from django.contrib.auth.models import User
from django.contrib.auth.models import AnonymousUser
from django.contrib.sessions.backends.db import SessionStore
from django.core.urlresolvers import NoReverseMatch
from django.core.urlresolvers import reverse
from django.http import HttpRequest
from django.test.client import RequestFactory

from . import utils
from . import config
from .connection import parse_redis_url, get_redis_connection
from .models import AccessAttempt
from .test import DefenderTestCase, DefenderTransactionTestCase


# Django >= 1.7 compatibility
try:
    LOGIN_FORM_KEY = '<form action="/admin/login/" method="post"'
    ' id="login-form">'
    ADMIN_LOGIN_URL = reverse('admin:login')
except NoReverseMatch:
    ADMIN_LOGIN_URL = reverse('admin:index')
    LOGIN_FORM_KEY = 'this_is_the_login_form'


VALID_USERNAME = VALID_PASSWORD = 'valid'


class AccessAttemptTest(DefenderTestCase):
    """ Test case using custom settings for testing
    """
    LOCKED_MESSAGE = 'Account locked: too many login attempts.'
    PERMANENT_LOCKED_MESSAGE = (
        LOCKED_MESSAGE + '  Contact an admin to unlock your account.'
    )

    def _get_random_str(self):
        """ Returns a random str """
        chars = string.ascii_uppercase + string.digits

        return ''.join(random.choice(chars) for x in range(20))

    def _login(self, username=None, password=None, user_agent='test-browser',
               remote_addr='127.0.0.1'):
        """ Login a user. If the username or password is not provided
        it will use a random string instead. Use the VALID_USERNAME and
        VALID_PASSWORD to make a valid login.
        """
        if username is None:
            username = self._get_random_str()

        if password is None:
            password = self._get_random_str()

        response = self.client.post(ADMIN_LOGIN_URL, {
            'username': username,
            'password': password,
            LOGIN_FORM_KEY: 1,
        }, HTTP_USER_AGENT=user_agent, REMOTE_ADDR=remote_addr)

        return response

    def setUp(self):
        """ Create a valid user for login
        """
        self.user = User.objects.create_superuser(
            username=VALID_USERNAME,
            email='test@example.com',
            password=VALID_PASSWORD,
        )

    def test_data_integrity_of_get_blocked_ips(self):
        """ Test whether data retrieved from redis via
        get_blocked_ips() is the same as the data saved
        """
        data_in = ['127.0.0.1', '4.2.2.1']
        for ip in data_in:
            utils.block_ip(ip)
        data_out = utils.get_blocked_ips()
        self.assertEqual(sorted(data_in), sorted(data_out))

    def test_data_integrity_of_get_blocked_usernames(self):
        """ Test whether data retrieved from redis via
        get_blocked_usernames() is the same as the data saved
        """
        data_in = ['foo', 'bar']
        for username in data_in:
            utils.block_username(username)
        data_out = utils.get_blocked_usernames()
        self.assertEqual(sorted(data_in), sorted(data_out))

    def test_login_get(self):
        """ visit the login page """
        response = self.client.get(ADMIN_LOGIN_URL)
        self.assertEquals(response.status_code, 200)

    def test_failure_limit_by_ip_once(self):
        """ Tests the login lock by ip when trying to login
        one more time than failure limit
        """
        for i in range(0, config.FAILURE_LIMIT):
            response = self._login()
            # Check if we are in the same login page
            self.assertContains(response, LOGIN_FORM_KEY)

        # So, we shouldn't have gotten a lock-out yet.
        # But we should get one now
        response = self._login()
        self.assertContains(response, self.LOCKED_MESSAGE)

        # doing a get should also get locked out message
        response = self.client.get(ADMIN_LOGIN_URL)
        self.assertContains(response, self.LOCKED_MESSAGE)

    def test_failure_limit_by_ip_many(self):
        """ Tests the login lock by ip when trying to
        login a lot of times more than failure limit
        """
        for i in range(0, config.FAILURE_LIMIT):
            response = self._login()
            # Check if we are in the same login page
            self.assertContains(response, LOGIN_FORM_KEY)

        # So, we shouldn't have gotten a lock-out yet.
        # But we should get one now
        for i in range(0, random.randrange(1, 10)):
            # try to log in a bunch of times
            response = self._login()
            self.assertContains(response, self.LOCKED_MESSAGE)

        # doing a get should also get locked out message
        response = self.client.get(ADMIN_LOGIN_URL)
        self.assertContains(response, self.LOCKED_MESSAGE)

    def test_failure_limit_by_username_once(self):
        """ Tests the login lock by username when trying to login
        one more time than failure limit
        """
        for i in range(0, config.FAILURE_LIMIT):
            ip = '74.125.239.{0}.'.format(i)
            response = self._login(username=VALID_USERNAME, remote_addr=ip)
            # Check if we are in the same login page
            self.assertContains(response, LOGIN_FORM_KEY)

        # So, we shouldn't have gotten a lock-out yet.
        # But we should get one now
        response = self._login()
        self.assertContains(response, self.LOCKED_MESSAGE)

        # doing a get should also get locked out message
        response = self.client.get(ADMIN_LOGIN_URL)
        self.assertContains(response, self.LOCKED_MESSAGE)

    def test_valid_login(self):
        """ Tests a valid login for a real username
        """
        response = self._login(username=VALID_USERNAME,
                               password=VALID_PASSWORD)
        self.assertNotContains(response, LOGIN_FORM_KEY, status_code=302)

    def test_reset_after_valid_login(self):
        """ Tests the counter gets reset after a valid login
        """
        for i in range(0, config.FAILURE_LIMIT):
            self._login(username=VALID_USERNAME)

        # now login with a valid username and password
        self._login(username=VALID_USERNAME, password=VALID_PASSWORD)

        # and we should be able to try again without hitting the failure limit
        response = self._login(username=VALID_USERNAME)
        self.assertNotContains(response, self.LOCKED_MESSAGE)

    def test_blocked_ip_cannot_login(self):
        """ Test an user with blocked ip cannot login with another username
        """
        for i in range(0, config.FAILURE_LIMIT + 1):
            response = self._login(username=VALID_USERNAME)

        # try to login with a different user
        response = self._login(username='myuser')
        self.assertContains(response, self.LOCKED_MESSAGE)

    def test_blocked_username_cannot_login(self):
        """ Test an user with blocked username cannot login using
        another ip
        """
        for i in range(0, config.FAILURE_LIMIT + 1):
            ip = '74.125.239.{0}.'.format(i)
            response = self._login(username=VALID_USERNAME, remote_addr=ip)

        # try to login with a different ip
        response = self._login(username=VALID_USERNAME, remote_addr='8.8.8.8')
        self.assertContains(response, self.LOCKED_MESSAGE)

    def test_cooling_off(self):
        """ Tests if the cooling time allows a user to login
        """
        self.test_failure_limit_by_ip_once()
        # Wait for the cooling off period
        time.sleep(config.COOLOFF_TIME)

        if config.MOCK_REDIS:
            # mock redis require that we expire on our own
            get_redis_connection().do_expire()  # pragma: no cover
        # It should be possible to login again, make sure it is.
        self.test_valid_login()

    def test_cooling_off_for_trusted_user(self):
        """ Test the cooling time for a trusted user
        """
        # Try the cooling off time
        self.test_cooling_off()

    def test_long_user_agent_valid(self):
        """ Tests if can handle a long user agent
        """
        long_user_agent = 'ie6' * 1024
        response = self._login(username=VALID_USERNAME, password=VALID_PASSWORD,
                               user_agent=long_user_agent)
        self.assertNotContains(response, LOGIN_FORM_KEY, status_code=302)

    @patch('defender.config.BEHIND_REVERSE_PROXY', True)
    @patch('defender.config.REVERSE_PROXY_HEADER', 'HTTP_X_FORWARDED_FOR')
    def test_get_ip_reverse_proxy(self):
        """ Tests if can handle a long user agent
        """
        request_factory = RequestFactory()
        request = request_factory.get(ADMIN_LOGIN_URL)
        request.user = AnonymousUser()
        request.session = SessionStore()

        request.META['HTTP_X_FORWARDED_FOR'] = '192.168.24.24'
        self.assertEquals(utils.get_ip(request), '192.168.24.24')

        request_factory = RequestFactory()
        request = request_factory.get(ADMIN_LOGIN_URL)
        request.user = AnonymousUser()
        request.session = SessionStore()

        request.META['REMOTE_ADDR'] = '24.24.24.24'
        self.assertEquals(utils.get_ip(request), '24.24.24.24')

    def test_get_ip(self):
        """ Tests if can handle a long user agent
        """
        request_factory = RequestFactory()
        request = request_factory.get(ADMIN_LOGIN_URL)
        request.user = AnonymousUser()
        request.session = SessionStore()

        self.assertEquals(utils.get_ip(request), '127.0.0.1')

    def test_long_user_agent_not_valid(self):
        """ Tests if can handle a long user agent with failure
        """
        long_user_agent = 'ie6' * 1024
        for i in range(0, config.FAILURE_LIMIT + 1):
            response = self._login(user_agent=long_user_agent)

        self.assertContains(response, self.LOCKED_MESSAGE)

    def test_reset_ip(self):
        """ Tests if can reset an ip address
        """
        # Make a lockout
        self.test_failure_limit_by_ip_once()

        # Reset the ip so we can try again
        utils.reset_failed_attempts(ip_address='127.0.0.1')

        # Make a login attempt again
        self.test_valid_login()

    @patch('defender.config.LOCKOUT_URL', 'http://localhost/othe/login/')
    def test_failed_login_redirect_to_URL(self):
        """ Test to make sure that after lockout we send to the correct
        redirect URL """

        for i in range(0, config.FAILURE_LIMIT):
            response = self._login()
            # Check if we are in the same login page
            self.assertContains(response, LOGIN_FORM_KEY)

        # So, we shouldn't have gotten a lock-out yet.
        # But we should get one now, check redirect make sure it is valid.
        response = self._login()
        self.assertEquals(response.status_code, 302)
        self.assertEquals(response['Location'], 'http://localhost/othe/login/')

        # doing a get should also get locked out message
        response = self.client.get(ADMIN_LOGIN_URL)
        self.assertEquals(response.status_code, 302)
        self.assertEquals(response['Location'], 'http://localhost/othe/login/')

    @patch('defender.config.LOCKOUT_URL', '/o/login/')
    def test_failed_login_redirect_to_URL_local(self):
        """ Test to make sure that after lockout we send to the correct
        redirect URL """

        for i in range(0, config.FAILURE_LIMIT):
            response = self._login()
            # Check if we are in the same login page
            self.assertContains(response, LOGIN_FORM_KEY)

        # So, we shouldn't have gotten a lock-out yet.
        # But we should get one now, check redirect make sure it is valid.
        response = self._login()
        self.assertEquals(response.status_code, 302)
        self.assertEquals(response['Location'], 'http://testserver/o/login/')

        # doing a get should also get locked out message
        response = self.client.get(ADMIN_LOGIN_URL)
        self.assertEquals(response.status_code, 302)
        self.assertEquals(response['Location'], 'http://testserver/o/login/')

    @patch('defender.config.LOCKOUT_TEMPLATE', 'defender/lockout.html')
    def test_failed_login_redirect_to_template(self):
        """ Test to make sure that after lockout we send to the correct
        template """

        for i in range(0, config.FAILURE_LIMIT):
            response = self._login()
            # Check if we are in the same login page
            self.assertContains(response, LOGIN_FORM_KEY)

        # So, we shouldn't have gotten a lock-out yet.
        # But we should get one now, check template make sure it is valid.
        response = self._login()
        self.assertEquals(response.status_code, 200)
        self.assertTemplateUsed(response, 'defender/lockout.html')

        # doing a get should also get locked out message
        response = self.client.get(ADMIN_LOGIN_URL)
        self.assertEquals(response.status_code, 200)
        self.assertTemplateUsed(response, 'defender/lockout.html')

    @patch('defender.config.COOLOFF_TIME', 0)
    def test_failed_login_no_cooloff(self):
        for i in range(0, config.FAILURE_LIMIT):
            response = self._login()
            # Check if we are in the same login page
            self.assertContains(response, LOGIN_FORM_KEY)

        # So, we shouldn't have gotten a lock-out yet.
        # But we should get one now, check redirect make sure it is valid.
        response = self._login()
        self.assertContains(response, self.PERMANENT_LOCKED_MESSAGE)

        # doing a get should also get locked out message
        response = self.client.get(ADMIN_LOGIN_URL)
        self.assertContains(response, self.PERMANENT_LOCKED_MESSAGE)

    def test_login_attempt_model(self):
        """ test the login model"""

        response = self._login()
        self.assertContains(response, LOGIN_FORM_KEY)
        self.assertEquals(AccessAttempt.objects.count(), 1)
        self.assertIsNotNone(str(AccessAttempt.objects.all()[0]))

    def test_is_valid_ip(self):
        """ Test the is_valid_ip() method """
        self.assertEquals(utils.is_valid_ip('192.168.0.1'), True)
        self.assertEquals(utils.is_valid_ip('130.80.100.24'), True)
        self.assertEquals(utils.is_valid_ip('8.8.8.8'), True)
        self.assertEquals(utils.is_valid_ip('127.0.0.1'), True)
        self.assertEquals(utils.is_valid_ip('fish'), False)
        self.assertEquals(utils.is_valid_ip(None), False)
        self.assertEquals(utils.is_valid_ip(''), False)
        self.assertEquals(utils.is_valid_ip('0x41.0x41.0x41.0x41'), False)
        self.assertEquals(utils.is_valid_ip('192.168.100.34.y'), False)
        self.assertEquals(
            utils.is_valid_ip('2001:0db8:85a3:0000:0000:8a2e:0370:7334'), True)
        self.assertEquals(
            utils.is_valid_ip('2001:db8:85a3:0:0:8a2e:370:7334'), True)
        self.assertEquals(
            utils.is_valid_ip('2001:db8:85a3::8a2e:370:7334'), True)
        self.assertEquals(
            utils.is_valid_ip('::ffff:192.0.2.128'), True)
        self.assertEquals(
            utils.is_valid_ip('::ffff:8.8.8.8'), True)

    def test_parse_redis_url(self):
        """ test the parse_redis_url method """
        # full regular
        conf = parse_redis_url("redis://user:password@localhost2:1234/2")
        self.assertEquals(conf.get('HOST'), 'localhost2')
        self.assertEquals(conf.get('DB'), 2)
        self.assertEquals(conf.get('PASSWORD'), 'password')
        self.assertEquals(conf.get('PORT'), 1234)

        # full non local
        conf = parse_redis_url("redis://user:pass@www.localhost.com:1234/2")
        self.assertEquals(conf.get('HOST'), 'www.localhost.com')
        self.assertEquals(conf.get('DB'), 2)
        self.assertEquals(conf.get('PASSWORD'), 'pass')
        self.assertEquals(conf.get('PORT'), 1234)

        # no user name
        conf = parse_redis_url("redis://password@localhost2:1234/2")
        self.assertEquals(conf.get('HOST'), 'localhost2')
        self.assertEquals(conf.get('DB'), 2)
        self.assertEquals(conf.get('PASSWORD'), None)
        self.assertEquals(conf.get('PORT'), 1234)

        # no user name 2 with colon
        conf = parse_redis_url("redis://:password@localhost2:1234/2")
        self.assertEquals(conf.get('HOST'), 'localhost2')
        self.assertEquals(conf.get('DB'), 2)
        self.assertEquals(conf.get('PASSWORD'), 'password')
        self.assertEquals(conf.get('PORT'), 1234)

        # Empty
        conf = parse_redis_url(None)
        self.assertEquals(conf.get('HOST'), 'localhost')
        self.assertEquals(conf.get('DB'), 0)
        self.assertEquals(conf.get('PASSWORD'), None)
        self.assertEquals(conf.get('PORT'), 6379)

        # no db
        conf = parse_redis_url("redis://:password@localhost2:1234")
        self.assertEquals(conf.get('HOST'), 'localhost2')
        self.assertEquals(conf.get('DB'), 0)
        self.assertEquals(conf.get('PASSWORD'), 'password')
        self.assertEquals(conf.get('PORT'), 1234)

        # no password
        conf = parse_redis_url("redis://localhost2:1234/0")
        self.assertEquals(conf.get('HOST'), 'localhost2')
        self.assertEquals(conf.get('DB'), 0)
        self.assertEquals(conf.get('PASSWORD'), None)
        self.assertEquals(conf.get('PORT'), 1234)

    def test_get_ip_address_from_request(self):
        req = HttpRequest()
        req.META['REMOTE_ADDR'] = '1.2.3.4'
        ip = utils.get_ip_address_from_request(req)
        self.assertEqual(ip, '1.2.3.4')

        req = HttpRequest()
        req.META['REMOTE_ADDR'] = '1.2.3.4 '
        ip = utils.get_ip_address_from_request(req)
        self.assertEqual(ip, '1.2.3.4')

        req = HttpRequest()
        req.META['REMOTE_ADDR'] = '192.168.100.34.y'
        ip = utils.get_ip_address_from_request(req)
        self.assertEqual(ip, '127.0.0.1')

        req = HttpRequest()
        req.META['REMOTE_ADDR'] = 'cat'
        ip = utils.get_ip_address_from_request(req)
        self.assertEqual(ip, '127.0.0.1')

        req = HttpRequest()
        ip = utils.get_ip_address_from_request(req)
        self.assertEqual(ip, '127.0.0.1')

    @patch('defender.config.BEHIND_REVERSE_PROXY', True)
    @patch('defender.config.REVERSE_PROXY_HEADER', 'HTTP_X_PROXIED')
    def test_get_ip_reverse_proxy_custom_header(self):
        req = HttpRequest()
        req.META['HTTP_X_PROXIED'] = '1.2.3.4'
        self.assertEqual(utils.get_ip(req), '1.2.3.4')

        req = HttpRequest()
        req.META['HTTP_X_PROXIED'] = '1.2.3.4, 5.6.7.8, 127.0.0.1'
        self.assertEqual(utils.get_ip(req), '1.2.3.4')

        req = HttpRequest()
        req.META['REMOTE_ADDR'] = '1.2.3.4'
        self.assertEqual(utils.get_ip(req), '1.2.3.4')

    @patch('defender.config.BEHIND_REVERSE_PROXY', True)
    @patch('defender.config.REVERSE_PROXY_HEADER', 'HTTP_X_REAL_IP')
    def test_get_user_attempts(self):
        ip_attempts = random.randint(3, 12)
        username_attempts = random.randint(3, 12)
        for i in range(0, ip_attempts):
            utils.increment_key(utils.get_ip_attempt_cache_key('1.2.3.4'))
        for i in range(0, username_attempts):
            utils.increment_key(utils.get_username_attempt_cache_key('foobar'))
        req = HttpRequest()
        req.POST['username'] = 'foobar'
        req.META['HTTP_X_REAL_IP'] = '1.2.3.4'
        self.assertEqual(
            utils.get_user_attempts(req), max(ip_attempts, username_attempts)
        )

        req = HttpRequest()
        req.POST['username'] = 'foobar'
        req.META['HTTP_X_REAL_IP'] = '5.6.7.8'
        self.assertEqual(
            utils.get_user_attempts(req), username_attempts
        )

        req = HttpRequest()
        req.POST['username'] = 'barfoo'
        req.META['HTTP_X_REAL_IP'] = '1.2.3.4'
        self.assertEqual(
            utils.get_user_attempts(req), ip_attempts
        )

    def test_admin(self):
        """ test the admin pages for this app """
        from .admin import AccessAttemptAdmin
        AccessAttemptAdmin

    def test_decorator_middleware(self):
        # because watch_login is called twice in this test (once by the
        # middleware and once by the decorator) we have half as many attempts
        # before getting locked out.
        # this is getting called twice, once for each decorator, not sure how
        # to dynamically remove one of the middlewares during a test so we
        # divide the failure limit by 2.

        for i in range(0, int(config.FAILURE_LIMIT)):
            response = self._login()
            # Check if we are in the same login page
            self.assertContains(response, LOGIN_FORM_KEY)

        # So, we shouldn't have gotten a lock-out yet.
        # But we should get one now
        response = self._login()
        self.assertContains(response, self.LOCKED_MESSAGE)

        # doing a get should also get locked out message
        response = self.client.get(ADMIN_LOGIN_URL)
        self.assertContains(response, self.LOCKED_MESSAGE)

    def test_get_view(self):
        """ Check that the decorator doesn't tamper with GET requests"""
        for i in range(0, config.FAILURE_LIMIT):
            response = self.client.get(ADMIN_LOGIN_URL)
            # Check if we are in the same login page
            self.assertContains(response, LOGIN_FORM_KEY)
        response = self.client.get(ADMIN_LOGIN_URL)
        self.assertNotContains(response, self.LOCKED_MESSAGE)

    @patch('defender.config.USE_CELERY', True)
    def test_use_celery(self):
        """ Check that use celery works"""

        self.assertEquals(AccessAttempt.objects.count(), 0)

        for i in range(0, int(config.FAILURE_LIMIT)):
            response = self._login()
            # Check if we are in the same login page
            self.assertContains(response, LOGIN_FORM_KEY)

        # So, we shouldn't have gotten a lock-out yet.
        # But we should get one now
        response = self._login()
        self.assertContains(response, self.LOCKED_MESSAGE)

        self.assertEquals(AccessAttempt.objects.count(),
                          config.FAILURE_LIMIT+1)
        self.assertIsNotNone(str(AccessAttempt.objects.all()[0]))

    @patch('defender.config.LOCKOUT_BY_IP_USERNAME', True)
    def test_lockout_by_ip_and_username(self):
        """Check that lockout still works when locking out by IP and Username combined"""

        username = 'testy'

        for i in range(0, config.FAILURE_LIMIT):
            response = self._login(username=username)
            # Check if we are in the same login page
            self.assertContains(response, LOGIN_FORM_KEY)

        # So, we shouldn't have gotten a lock-out yet.
        # But we should get one now
        response = self._login(username=username)
        self.assertContains(response, self.LOCKED_MESSAGE)

        # We shouldn't get a lockout message when attempting to use no username
        response = self.client.get(ADMIN_LOGIN_URL)
        self.assertContains(response, LOGIN_FORM_KEY)

        # We shouldn't get a lockout message when attempting to use a different username
        response = self._login()
        self.assertContains(response, LOGIN_FORM_KEY)

        # We shouldn't get a lockout message when attempting to use a different ip address
        ip = '74.125.239.60'
        response = self._login(username=VALID_USERNAME, remote_addr=ip)
        # Check if we are in the same login page
        self.assertContains(response, LOGIN_FORM_KEY)


class DefenderTestCaseTest(DefenderTestCase):
    """Make sure that we're cleaning the cache between tests"""
    key = 'test_key'

    def test_first_incr(self):
        utils.REDIS_SERVER.incr(self.key)
        result = int(utils.REDIS_SERVER.get(self.key))
        self.assertEqual(result, 1)

    def test_second_incr(self):
        utils.REDIS_SERVER.incr(self.key)
        result = int(utils.REDIS_SERVER.get(self.key))
        self.assertEqual(result, 1)


class DefenderTransactionTestCaseTest(DefenderTransactionTestCase):
    """Make sure that we're cleaning the cache between tests"""
    key = 'test_key'

    def test_first_incr(self):
        utils.REDIS_SERVER.incr(self.key)
        result = int(utils.REDIS_SERVER.get(self.key))
        self.assertEqual(result, 1)

    def test_second_incr(self):
        utils.REDIS_SERVER.incr(self.key)
        result = int(utils.REDIS_SERVER.get(self.key))
        self.assertEqual(result, 1)