# -*- coding: utf-8 -*-
"""sec-ch-ua 系列请求头：为什么必须带、怎么还原。

抖音网关对「声称自己是 Chrome、却没带 sec-ch-ua」的请求会回 **200 + 空 body** ——
不报错、不给原因、HTTP 状态还是成功的，采集侧只看到 0 条。实测同一 URL、同一 cookie、
同一参数：不带头 0 字节，补上这三个头 7077 字节。
"""

import pytest

from media_platform.douyin.help import client_hint_headers

# 实测从真实浏览器抓到的 navigator.userAgentData
REAL_UA_DATA = {
    "brands": [
        {"brand": "Google Chrome", "version": "155"},
        {"brand": "Chromium", "version": "155"},
        {"brand": "Not(A:Brand", "version": "24"},
    ],
    "mobile": False,
    "platform": "Linux",
}


def test_headers_are_derived_from_user_agent_data():
    hints = client_hint_headers(REAL_UA_DATA)

    assert hints["sec-ch-ua"] == (
        '"Google Chrome";v="155", "Chromium";v="155", "Not(A:Brand";v="24"'
    )
    assert hints["sec-ch-ua-mobile"] == "?0"
    assert hints["sec-ch-ua-platform"] == '"Linux"'


def test_mobile_is_reflected():
    hints = client_hint_headers({**REAL_UA_DATA, "mobile": True})

    assert hints["sec-ch-ua-mobile"] == "?1"


@pytest.mark.parametrize("value", [None, [], "not-a-dict", {}, {"brands": []}])
def test_nothing_is_invented_when_user_agent_data_is_unavailable(value):
    """拿不到就返回空。

    凭空造一组和 UA 对不上的头，只会变成**另一个**可疑特征 —— 那比不带头更糟。
    """
    assert client_hint_headers(value) == {}


def test_missing_platform_still_sends_the_other_two():
    hints = client_hint_headers({"brands": REAL_UA_DATA["brands"], "mobile": False})

    assert "sec-ch-ua" in hints
    assert "sec-ch-ua-mobile" in hints
    assert "sec-ch-ua-platform" not in hints