# Tests for waeup.cas.authentictors
import os
import threading
import unittest
from paste.deploy import loadapp
try:
    from SimpleXMLRPCServer import SimpleXMLRPCServer  # Python 2.x
except ImportError:
    from xmlrpc.server import SimpleXMLRPCServer       # Python 3.x
try:
    import xmlrpclib                     # Python 2.x
except ImportError:
    import xmlrpc.client as xmlrpclib    # Python 3.x
from waeup.cas.authenticators import (
    get_all_authenticators, get_authenticator, filter_auth_opts,
    Authenticator, DummyAuthenticator, KofaAuthenticator
    )
from waeup.cas.server import CASServer


class TestHelpers(unittest.TestCase):

    def test_get_all_authenticators(self):
        # we can get authenticators via entry points
        auths = get_all_authenticators()
        assert 'dummy' in auths
        assert auths['dummy'] is DummyAuthenticator

    def test_filter_auth_opts(self):
        # we can filter auth opts
        result = filter_auth_opts(
            dict(auth='foo', auth_bar='baz', auth_baz='blah')
            )
        assert result == (
            {'auth': 'foo'},
            {'auth_bar': 'baz', 'auth_baz': 'blah'}
            )

    def test_get_authenticator(self):
        # we can parse a paste.deploy config dict for auth
        result = get_authenticator({})
        assert result == {}
        result = get_authenticator({'auth': 'dummy'})
        assert isinstance(result['auth'], DummyAuthenticator)


class AuthenticatorTests(unittest.TestCase):

    def test_create(self):
        # we can create Authenticator instances
        auth = Authenticator()
        assert isinstance(auth, Authenticator)


class DummyAuthenticatorTests(unittest.TestCase):

    def test_create(self):
        # we can create DummyAuthenticator instances
        auth = DummyAuthenticator()
        assert isinstance(auth, DummyAuthenticator)

    def test_check_credentials(self):
        # we can succeed with 'bird'/'bebop'. Others will fail.
        auth = DummyAuthenticator()
        result1 = auth.check_credentials('bird', 'bebop')
        assert result1 == (True, '')
        result2 = auth.check_credentials('foo', 'bar')
        assert result2 == (False, 'Invalid username or password.')


BACKENDS1 = dict(
    inst1=dict(
        url='http://localhost:6666/app',
        marker='^MA-',
        )
    )

BACKENDS2 = dict(
    inst1=dict(
        url='http://localhost:6666/',
        marker='^SCHOOL1-',
        )
    )


class KofaAuthenticatorTests(unittest.TestCase):

    def test_create(self):
        # we can create KofaAuthenticator instances
        auth = KofaAuthenticator()
        assert isinstance(auth, KofaAuthenticator)

    def test_options_defaults(self):
        # all options have sensible defaults
        auth = KofaAuthenticator()
        assert auth.backends == {}

    def test_options(self):
        # we can pass options
        auth = KofaAuthenticator(auth_backends=str(BACKENDS1))
        assert auth.backends == BACKENDS1
        auth = KofaAuthenticator(auth_backends='{"foo": {"url": "bar"}}')
        assert auth.backends['foo']['marker'] == '.+'
        self.assertRaises(
            ValueError, KofaAuthenticator, auth_backends='not-a-py-expr')
        self.assertRaises(
            ValueError, KofaAuthenticator, auth_backends='"Not a dict"')
        self.assertRaises(
            ValueError, KofaAuthenticator,
            auth_backends='{"foo": "not-a-dict"}')
        self.assertRaises(
            ValueError, KofaAuthenticator,
            auth_backends='{"foo": {"no-url-key": "bar"}}')
        self.assertRaises(
            ValueError, KofaAuthenticator,
            auth_backends='{"foo": {"url": "bar", "marker": "inv_re)"}}')

    def test_paste_deploy_options(self):
        # we can set CAS server-related options via paste.deploy config
        paste_conf = os.path.join(
            os.path.dirname(__file__), 'sample3.ini')
        app = loadapp('config:%s' % paste_conf)
        assert isinstance(app, CASServer)
        assert app.db_connection_string == 'sqlite:///:memory:'
        assert isinstance(app.auth, KofaAuthenticator)


class FakeKofaServer(SimpleXMLRPCServer):
    # A fake Kofa server that provides only XMLRPC methods

    allow_reuse_address = True

    def __init__(self, *args, **kw):
        kw.update(allow_none=True)
        SimpleXMLRPCServer.__init__(self, *args, **kw)
        self.register_function(
            self._check_credentials, 'check_applicant_credentials')
        self.register_function(
            self._check_credentials, 'check_student_credentials')

    def _check_credentials(self, username, password):
        # fake waeup.kofa check_credentials method.
        #
        # This method is supposed to mimic the behaviour of an
        # original waeup.kofa check_credentials method. It returns a
        # positive result for the credentials `bird`/`bebop`.
        if username == 'bird' and password == 'bebop':
            return {'id': 'bird', 'email': 'bird@gods.net',
                    'description': 'Mr. Charles Parker'}
        return None


class KofaAuthenticatorIntegrationTests(unittest.TestCase):
    # A test case where a fake Kofa server is started before tests (and
    # shut down afterwards).

    server = None
    th = None

    @classmethod
    def setUpClass(cls):
        # set up a fake kofa server
        cls.server = FakeKofaServer(('localhost', 6666))
        cls.th = threading.Thread(target=cls.server.serve_forever)
        cls.th.daemon = True
        cls.th.start()

    @classmethod
    def tearDownClass(cls):
        # tear down fake kofa server
        cls.server.shutdown()
        cls.server.server_close()

    def test_fake_kofa_works(self):
        # make sure the local fake kofa works
        proxy = xmlrpclib.ServerProxy("http://localhost:6666", allow_none=True)
        result = proxy.check_student_credentials('bird', 'bebop')
        assert result == {
            'description': 'Mr. Charles Parker',
            'email': 'bird@gods.net',
            'id': 'bird'}
        result = proxy.check_applicant_credentials('bird', 'bebop')
        assert result == {
            'description': 'Mr. Charles Parker',
            'email': 'bird@gods.net',
            'id': 'bird'}
        return

    def test_check_credentials(self):
        # we get real responses when querying Kofa instances
        auth = KofaAuthenticator(auth_backends=str(BACKENDS2))
        result1 = auth.check_credentials('SCHOOL1-bird', 'bebop')
        assert result1 == (True, '')
        result2 = auth.check_credentials('SCHOOL1-foo', 'bar')
        assert result2 == (False, 'Invalid username or password.')
        result3 = auth.check_credentials('SCHOOL2-bar', 'baz')
        assert result3 == (False, 'Invalid username or password.')