import base64
import json
import uuid
from unittest.mock import ANY, MagicMock, patch

from authlib.integrations.base_client import OAuthError
from django.shortcuts import redirect
from django.test import override_settings, TestCase
from django.urls import reverse

from vbv_lernwelt.core.models import User
from vbv_lernwelt.course.consts import COURSE_VERSICHERUNGSVERMITTLERIN_ID
from vbv_lernwelt.course.creators.test_utils import (
    add_course_session_user,
    create_course,
    create_course_session,
)
from vbv_lernwelt.course.models import CourseSession, CourseSessionUser
from vbv_lernwelt.importer.services import create_or_update_user


def decoded_token(email, oid=None, given_name="Bobby", family_name="Table"):
    return {
        "email": email,
        "oid": oid or uuid.uuid4(),
        "given_name": given_name,
        "family_name": family_name,
    }


class TestSignInAuthorizeSSO(TestCase):
    def setUp(self):
        CourseSession.objects.all().delete()
        User.objects.all().delete()

    @override_settings(OAUTH={"client_name": "mock"})
    @patch("vbv_lernwelt.sso.views.oauth")
    @patch("vbv_lernwelt.sso.views.decode_jwt")
    def test_authorize_first_time_uk(self, mock_decode_jwt, mock_oauth):
        # GIVEN
        email = "user@example.com"
        token = decoded_token(email)

        mock_decode_jwt.return_value = token
        mock_oauth.signin.authorize_access_token.return_value = {
            "id_token": "<some-token-irrelevant-for-this-test>"
        }

        state = base64.urlsafe_b64encode(
            json.dumps({"course": "uk", "next": "/shall-be-ignored"}).encode()
        ).decode()

        # WHEN
        response = self.client.get(reverse("sso:authorize"), {"state": state})

        # THEN
        self.assertEqual(302, response.status_code)
        self.assertEqual("/onboarding/uk/account/create", response.url)  # noqa

        user = User.objects.get(email=email)  # noqa
        self.assertIsNotNone(user)

        self.assertEqual(user.email, email)
        self.assertEqual(user.first_name, token["given_name"])
        self.assertEqual(user.last_name, token["family_name"])
        self.assertEqual(user.sso_id, token["oid"])

    @override_settings(OAUTH={"client_name": "mock"})
    @patch("vbv_lernwelt.sso.views.oauth")
    @patch("vbv_lernwelt.sso.views.decode_jwt")
    def test_authorize_first_time_vv(self, mock_decode_jwt, mock_oauth):
        # GIVEN
        email = "user@example.com"
        token = decoded_token(email)

        mock_decode_jwt.return_value = token
        mock_oauth.signin.authorize_access_token.return_value = {
            "id_token": "<some-token-irrelevant-for-this-test>"
        }

        state = base64.urlsafe_b64encode(
            json.dumps({"course": "vv-de", "next": "/shall-be-ignored"}).encode()
        ).decode()

        # WHEN
        response = self.client.get(reverse("sso:authorize"), {"state": state})

        # THEN
        self.assertEqual(302, response.status_code)
        self.assertEqual("/onboarding/vv-de/account/create", response.url)  # noqa

        user = User.objects.get(email=email)  # noqa
        self.assertIsNotNone(user)

        self.assertEqual(user.email, email)
        self.assertEqual(user.first_name, token["given_name"])
        self.assertEqual(user.last_name, token["family_name"])
        self.assertEqual(user.sso_id, token["oid"])

    @patch("vbv_lernwelt.sso.views.oauth")
    def test_authorize_on_tampered_token(self, mock_oauth_service):
        # GIVEN
        mock_oauth_service.signin.authorize_access_token.side_effect = OAuthError()

        # WHEN
        response = self.client.get(reverse("sso:authorize"))

        # THEN
        self.assertEqual(302, response.status_code)
        self.assertEqual("/", response.url)  # noqa

    @override_settings(OAUTH={"client_name": "mock"})
    @patch("vbv_lernwelt.sso.views.oauth")
    @patch("vbv_lernwelt.sso.views.decode_jwt")
    def test_authorize_onboarded_uk(self, mock_decode_jwt, mock_oauth):
        # GIVEN
        email = "some@email.com"
        token = decoded_token(email)
        mock_decode_jwt.return_value = token
        mock_oauth.signin.authorize_access_token.return_value = {
            "id_token": "<some-token-irrelevant-for-this-test>"
        }

        # create a user that is already onboarded for UK
        user = create_or_update_user(
            email=email,
            sso_id=str(token["oid"]),
            first_name=token["given_name"],
            last_name=token["family_name"],
        )

        course, _ = create_course("uk")
        course_session = create_course_session(course, "UK", "2023")
        add_course_session_user(course_session, user, CourseSessionUser.Role.MEMBER)

        self.assertIsNotNone(User.objects.get(email=email))

        # WHEN
        state = base64.urlsafe_b64encode(json.dumps({"course": "uk"}).encode()).decode()
        response = self.client.get(reverse("sso:authorize"), {"state": state})

        # THEN
        self.assertEqual(302, response.status_code)
        self.assertEqual("/", response.url)  # noqa

    @override_settings(OAUTH={"client_name": "mock"})
    @patch("vbv_lernwelt.sso.views.oauth")
    @patch("vbv_lernwelt.sso.views.decode_jwt")
    def test_authorize_onboarded_vv(self, mock_decode_jwt, mock_oauth):
        # GIVEN
        email = "some@email.com"
        token = decoded_token(email)
        mock_decode_jwt.return_value = token
        mock_oauth.signin.authorize_access_token.return_value = {
            "id_token": "<some-token-irrelevant-for-this-test>"
        }

        # create a user that is already onboarded for UK
        user = create_or_update_user(
            email=email,
            sso_id=str(token["oid"]),
            first_name=token["given_name"],
            last_name=token["family_name"],
        )

        course, _ = create_course(_id=COURSE_VERSICHERUNGSVERMITTLERIN_ID, title="VV")
        course_session = create_course_session(course, "VV", "VV")
        add_course_session_user(course_session, user, CourseSessionUser.Role.MEMBER)

        self.assertIsNotNone(User.objects.get(email=email))

        # WHEN
        state = base64.urlsafe_b64encode(json.dumps({"course": "vv"}).encode()).decode()
        response = self.client.get(reverse("sso:authorize"), {"state": state})

        # THEN
        self.assertEqual(302, response.status_code)
        self.assertEqual("/", response.url)  # noqa

    @override_settings(OAUTH={"client_name": "mock"})
    @patch("vbv_lernwelt.sso.views.oauth")
    @patch("vbv_lernwelt.sso.views.decode_jwt")
    def test_authorize_next_url(self, mock_decode_jwt, mock_oauth):
        # GIVEN
        next_url = "/some/next/url"

        mock_decode_jwt.return_value = decoded_token("whatever@example.com")
        mock_oauth.signin.authorize_access_token.return_value = {
            "id_token": "<some-token-irrelevant-for-this-test>"
        }

        # WHEN
        state = base64.urlsafe_b64encode(
            json.dumps({"next": next_url}).encode()
        ).decode()

        response = self.client.get(reverse("sso:authorize"), {"state": state})

        # THEN
        self.assertEqual(302, response.status_code)
        self.assertEqual(next_url, response.url)  # noqa


class TestSignIn(TestCase):
    @override_settings(OAUTH_SIGNIN_REDIRECT_URI="/sso/callback")
    @patch("vbv_lernwelt.sso.views.oauth")
    def test_signin_with_course_param(self, mock_oauth):
        # GIVEN
        course_param = "vv-de"

        expected_state = {"course": course_param, "next": None}
        expected_state_encoded = base64.urlsafe_b64encode(
            json.dumps(expected_state).encode()
        ).decode()

        mock_oauth.signin.authorize_redirect = MagicMock()
        mock_oauth.signin.authorize_redirect.return_value = redirect(
            "/just/here/to/return/a/redirect/object"
        )

        # WHEN
        self.client.get(
            reverse("sso:login"),
            {"course": course_param},
        )

        # THEN
        mock_oauth.signin.authorize_redirect.assert_called_once_with(
            ANY,
            "/sso/callback",
            state=expected_state_encoded,
            ui_locales="de",
        )

    @override_settings(OAUTH_SIGNIN_REDIRECT_URI="/sso/callback")
    @patch("vbv_lernwelt.sso.views.oauth")
    def test_signin_with_state_param(self, mock_oauth):
        # GIVEN
        course = "vv-de"

        state_param = base64.urlsafe_b64encode(
            json.dumps({"course": course, "next": None}).encode()
        ).decode()

        expected_state = {"course": course, "next": None}
        expected_state_encoded = base64.urlsafe_b64encode(
            json.dumps(expected_state).encode()
        ).decode()

        mock_oauth.signin.authorize_redirect = MagicMock()
        mock_oauth.signin.authorize_redirect.return_value = redirect(
            "/just/here/to/return/a/redirect/object"
        )

        # WHEN
        self.client.get(
            reverse("sso:login"),
            {"state": state_param},
        )

        # THEN
        mock_oauth.signin.authorize_redirect.assert_called_once_with(
            ANY,
            "/sso/callback",
            state=expected_state_encoded,
            ui_locales="de",
        )

    @override_settings(OAUTH_SIGNIN_REDIRECT_URI="/sso/callback")
    @patch("vbv_lernwelt.sso.views.oauth")
    def test_signin_next_url(self, mock_oauth):
        # GIVEN
        next_url = "/some/next/url"

        expected_state = {"course": None, "next": next_url}
        expected_state_encoded = base64.urlsafe_b64encode(
            json.dumps(expected_state).encode()
        ).decode()

        mock_oauth.signin.authorize_redirect = MagicMock()
        mock_oauth.signin.authorize_redirect.return_value = redirect(
            "/just/here/to/return/a/redirect/object"
        )

        # WHEN
        self.client.get(
            reverse("sso:login"),
            {"next": next_url},
        )

        # THEN
        mock_oauth.signin.authorize_redirect.assert_called_once_with(
            ANY,
            "/sso/callback",
            state=expected_state_encoded,
            ui_locales=ANY,
        )

    @override_settings(OAUTH_SIGNIN_REDIRECT_URI="/sso/callback")
    @patch("vbv_lernwelt.sso.views.oauth")
    def test_signin_language(self, mock_oauth):
        # GIVEN
        language = "fr"

        mock_oauth.signin.authorize_redirect = MagicMock()
        mock_oauth.signin.authorize_redirect.return_value = redirect(
            "/just/here/to/return/a/redirect/object"
        )

        # WHEN
        self.client.get(
            reverse("sso:login"),
            {"lang": language},
        )

        # THEN
        mock_oauth.signin.authorize_redirect.assert_called_once_with(
            ANY,
            "/sso/callback",
            state=ANY,
            ui_locales=language,
        )


class TestSignUp(TestCase):
    @override_settings(OAUTH_SIGNUP_REDIRECT_URI="/sso/login")
    @patch("vbv_lernwelt.sso.views.oauth")
    def test_signup_with_course_param(self, mock_oauth):
        # GIVEN
        course_param = "vv-de"
        next_param = "/some-next-url"
        language = "fr"

        expected_state = {"course": course_param, "next": next_param}
        expected_state_encoded = base64.urlsafe_b64encode(
            json.dumps(expected_state).encode()
        ).decode()

        mock_oauth.signup.authorize_redirect = MagicMock()
        mock_oauth.signup.authorize_redirect.return_value = redirect(
            "/just/here/to/return/a/redirect/object"
        )

        # WHEN
        self.client.get(
            reverse("sso:signup"),
            {"course": course_param, "next": next_param, "lang": language},
        )

        # THEN
        mock_oauth.signup.authorize_redirect.assert_called_once_with(
            ANY,
            "/sso/login",
            state=expected_state_encoded,
            lang=language,
        )