from base64 import b64decode

import unittest

from urllib.parse import unquote
from urllib.parse import urlparse, parse_qs

from pydiscourse import sso
from pydiscourse.exceptions import DiscourseError


class SSOTestCase(unittest.TestCase):

    def setUp(self):
        # values from https://meta.discourse.org/t/official-single-sign-on-for-discourse/13045
        self.secret = "d836444a9e4084d5b224a60c208dce14"
        self.nonce = "cb68251eefb5211e58c00ff1395f0c0b"
        self.payload = "bm9uY2U9Y2I2ODI1MWVlZmI1MjExZTU4YzAwZmYxMzk1ZjBjMGI%3D%0A"
        self.signature = "2828aa29899722b35a2f191d34ef9b3ce695e0e6eeec47deb46d588d70c7cb56"

        self.name = u"sam"
        self.username = u"samsam"
        self.external_id = u"hello123"
        self.email = u"test@test.com"
        self.redirect_url = u"/session/sso_login?sso=bm9uY2U9Y2I2ODI1MWVlZmI1MjExZTU4YzAwZmYxMzk1ZjBjMGImbmFtZT1z%0AYW0mdXNlcm5hbWU9c2Ftc2FtJmVtYWlsPXRlc3QlNDB0ZXN0LmNvbSZleHRl%0Acm5hbF9pZD1oZWxsbzEyMw%3D%3D%0A&sig=1c884222282f3feacd76802a9dd94e8bc8deba5d619b292bed75d63eb3152c0b"

    def test_missing_args(self):
        with self.assertRaises(DiscourseError):
            sso.sso_validate(None, self.signature, self.secret)

        with self.assertRaises(DiscourseError):
            sso.sso_validate("", self.signature, self.secret)

        with self.assertRaises(DiscourseError):
            sso.sso_validate(self.payload, None, self.secret)

    def test_invalid_signature(self):
        with self.assertRaises(DiscourseError):
            sso.sso_validate(self.payload, "notavalidsignature", self.secret)

    def test_valid_nonce(self):
        nonce = sso.sso_validate(self.payload, self.signature, self.secret)
        self.assertEqual(nonce, self.nonce)

    def test_valid_redirect_url(self):
        url = sso.sso_redirect_url(
            self.nonce,
            self.secret,
            self.email,
            self.external_id,
            self.username,
            name="sam",
        )

        self.assertIn("/session/sso_login", url[:20])

        # check its valid, using our own handy validator
        params = parse_qs(urlparse(url).query)
        payload = params["sso"][0]
        sso.sso_validate(payload, params["sig"][0], self.secret)

        # check the params have all the data we expect
        payload = b64decode(payload.encode("utf-8")).decode("utf-8")
        payload = unquote(payload)
        payload = dict((p.split("=") for p in payload.split("&")))

        self.assertEqual(
            payload,
            {
                "username": self.username,
                "nonce": self.nonce,
                "external_id": self.external_id,
                "name": self.name,
                "email": self.email,
            },
        )