"""Per-device preferences: cookies in, validated values out (AD-15)."""

import pytest
from django.test import Client, RequestFactory

from portal.shell import preferences
from portal.shell.preferences import Preferences


def request_with(cookies=None, accept_language=""):
    request = RequestFactory().get("/", HTTP_ACCEPT_LANGUAGE=accept_language)
    request.COOKIES.update(cookies or {})
    return request


def test_without_cookies_the_defaults_apply():
    prefs = preferences.from_request(request_with())
    assert prefs == Preferences(theme="system", language="en", form="sie")


@pytest.mark.parametrize(
    ("header", "expected"),
    [("de-DE,de;q=0.9,en;q=0.5", "de"), ("en-GB", "en"), ("fr-FR", "en"), ("", "en")],
)
def test_the_language_defaults_from_the_browser(header, expected):
    assert preferences.from_request(request_with(accept_language=header)).language == expected


def test_valid_cookies_are_used_and_beat_the_browser():
    cookies = {"pm_theme": "dark", "pm_lang": "en", "pm_form": "du"}
    prefs = preferences.from_request(request_with(cookies, accept_language="de"))
    assert prefs == Preferences(theme="dark", language="en", form="du")


@pytest.mark.parametrize("value", ["", "blue", "<script>", "DARK", "x" * 500])
def test_forged_cookie_values_fall_back_to_the_defaults(value):
    cookies = {"pm_theme": value, "pm_lang": value, "pm_form": value}
    prefs = preferences.from_request(request_with(cookies))
    assert prefs == Preferences(theme="system", language="en", form="sie")


def test_the_informal_form_only_changes_german():
    assert Preferences(language="de", form="du").language_code == "de-du"
    assert Preferences(language="de", form="sie").language_code == "de"
    assert Preferences(language="en", form="du").language_code == "en"


def test_only_valid_choices_are_taken_from_a_submission():
    assert preferences.chosen({"theme": "dark", "language": "xx", "form": "du"}) == {
        "pm_theme": "dark",
        "pm_form": "du",
    }
    assert preferences.chosen({}) == {}


# -- the preferences address ------------------------------------------------------------------


def test_choosing_sets_the_cookies_and_returns_to_the_page():
    response = Client().post(
        "/preferences", {"theme": "dark", "language": "de", "form": "du", "next": "/x?y=1"}
    )
    assert response.status_code == 302 and response["Location"] == "/x?y=1"
    for name, value in (("pm_theme", "dark"), ("pm_lang", "de"), ("pm_form", "du")):
        cookie = response.cookies[name]
        assert cookie.value == value
        assert cookie["samesite"] == "Lax" and cookie["secure"] and not cookie["httponly"]
        assert cookie["max-age"] == preferences.COOKIE_MAX_AGE


def test_an_invalid_value_sets_no_cookie():
    response = Client().post("/preferences", {"theme": "neon", "language": "fr"})
    assert not response.cookies


@pytest.mark.parametrize("target", ["https://evil.example.test/", "//evil.example.test", "x", ""])
def test_the_return_address_cannot_leave_the_site(target):
    response = Client().post("/preferences", {"theme": "dark", "next": target})
    assert response["Location"] == "/"


def test_choosing_needs_post():
    assert Client().get("/preferences").status_code == 405


def test_choosing_needs_a_csrf_token():
    strict = Client(enforce_csrf_checks=True)
    assert strict.post("/preferences", {"theme": "dark"}).status_code == 403