"""虎牙 Cookie 规范化工具。"""

from __future__ import annotations

import json
from collections.abc import Iterable, Mapping

from requests.cookies import RequestsCookieJar


def cookie_pairs(cookie: str) -> list[tuple[str, str]]:
    """把浏览器 Cookie 字符串拆成 key/value 对。"""
    pairs: list[tuple[str, str]] = []
    for part in (cookie or "").split(";"):
        item = part.strip()
        if not item or "=" not in item:
            continue
        key, value = item.split("=", 1)
        key = key.strip()
        if not key:
            continue
        pairs.append((key, value.strip()))
    return pairs


def normalize_cookie_pairs(pairs: Iterable[tuple[str, str]]) -> str:
    """按 Cookie key 去重，保留最后一次出现的值。"""
    ordered_keys: list[str] = []
    values: dict[str, str] = {}
    for raw_key, raw_value in pairs:
        key = str(raw_key).strip()
        if not key:
            continue
        if key not in values:
            ordered_keys.append(key)
        values[key] = "" if raw_value is None else str(raw_value).strip()
    return "; ".join(f"{key}={values[key]}" for key in ordered_keys)


def normalize_huya_cookie(
    cookie: str | Mapping[str, str] | RequestsCookieJar | None,
) -> str:
    """把 Cookie 字符串、dict 或 CookieJar 转成去重后的浏览器 Cookie 字符串。"""
    if not cookie:
        return ""
    if isinstance(cookie, str):
        return normalize_cookie_pairs(cookie_pairs(cookie))
    return normalize_cookie_pairs(
        [
            (str(key), "" if value is None else str(value))
            for key, value in cookie.items()
        ]
    )


def cookie_value(
    cookie: str | Mapping[str, str] | RequestsCookieJar | None, key: str
) -> str:
    """从 Cookie 中读取 key；有重复时以最后一次出现为准。"""
    if not cookie or not key:
        return ""
    if isinstance(cookie, str):
        pairs = cookie_pairs(cookie)
    else:
        pairs = list(cookie.items())
    value = ""
    for item_key, item_value in pairs:
        if item_key == key:
            value = "" if item_value is None else str(item_value).strip()
    return value


def browser_login_script(
    pairs: Mapping[str, str],
    target_url: str,
    *,
    domain: str = ".huya.com",
    ttl_days: int = 180,
    secure: bool = True,
) -> str:
    """生成在用户自己浏览器控制台执行的登录脚本。

    脚本把 Cookie 写入指定域后跳转目标页；Cookie 值以 JSON 数组内联，
    保证引号、反斜杠等字符安全转义。属性与扩展注入保持一致（默认 Secure），
    并先校验当前页面确实在 huya.com 域下——否则 document.cookie 会静默失效，
    操作者会以为已登录。
    """
    payload = json.dumps(
        [[key, value] for key, value in pairs.items()], ensure_ascii=False
    )
    target = json.dumps(target_url, ensure_ascii=False)
    ttl_ms = max(1, ttl_days) * 86_400_000
    suffix = ";secure" if secure else ""
    return (
        f"(function(){{"
        f"if(!/(^|\\.)huya\\.com$/i.test(location.hostname)){{"
        f"alert('请在 huya.com 域下的页面执行本脚本，当前页面：'+location.hostname);"
        f"return;}}"
        f"var c={payload};"
        f"var e=new Date(Date.now()+{ttl_ms}).toUTCString();"
        f"for(var i=0;i<c.length;i++){{"
        f"document.cookie=c[i][0]+'='+c[i][1]+';domain={domain};path=/;expires='+e+'{suffix}';"
        f"}}"
        f"location.href={target};"
        f"}})();"
    )