import ipaddress
import threading
import time
import uuid
from concurrent.futures import ThreadPoolExecutor
from contextvars import Context, copy_context
from dataclasses import dataclass, field
from typing import Any, Callable, Optional, Protocol
from urllib.parse import urlparse

from app.runtime.log import logger
from app.runtime.settings import RuntimeSettingsCompat
from app.runtime.managed_resources import (
    acquire_managed_resource,
    acquire_managed_resource_async,
)
from app.adapters.network.http import RequestUtils, cookie_parse


# 保留旧插件可覆盖的模块级入口，默认通过 runtime 代理动态读取浏览器配置。
settings = RuntimeSettingsCompat()


class BrowserElement(Protocol):
    """
    页面元素的最小接口，避免为了类型标注直接导入 Playwright。
    """

    def is_visible(self) -> bool:
        """判断元素是否可见。"""
        ...

    def fill(self, value: str) -> None:
        """向元素输入文本。"""
        ...

    def inner_text(self) -> str:
        """获取元素可见文本。"""
        ...


class BrowserContext(Protocol):
    """
    CloakBrowser 返回的上下文只需要满足这些能力即可。
    """

    def new_page(self) -> "BrowserPage":
        """创建新的浏览器页面。"""
        ...

    def cookies(self) -> list[dict[str, Any]]:
        """返回当前上下文 Cookie。"""
        ...

    def close(self) -> None:
        """关闭浏览器上下文。"""
        ...


class BrowserPage(Protocol):
    """
    CloakBrowser 页面对象的最小接口，覆盖 helper 和登录流程当前用到的方法。
    """

    context: BrowserContext
    url: str

    def set_extra_http_headers(self, headers: dict[str, str]) -> None:
        """设置页面额外请求头。"""
        ...

    def set_default_timeout(self, timeout: int) -> None:
        """设置页面默认超时时间。"""
        ...

    def goto(self, url: str, *args: Any, **kwargs: Any) -> Any:
        """导航到指定 URL。"""
        ...

    def wait_for_load_state(self, state: str, *args: Any, **kwargs: Any) -> Any:
        """等待页面加载状态。"""
        ...

    def wait_for_selector(self, selector: str, *args: Any, **kwargs: Any) -> Any:
        """等待指定选择器出现。"""
        ...

    def fill(self, selector: str, value: str, *args: Any, **kwargs: Any) -> Any:
        """向指定选择器输入文本。"""
        ...

    def click(self, selector: str, *args: Any, **kwargs: Any) -> Any:
        """点击指定选择器。"""
        ...

    def select_option(self, selector: str, *args: Any, **kwargs: Any) -> Any:
        """选择下拉框选项。"""
        ...

    def query_selector(self, selector: str) -> Optional[BrowserElement]:
        """查询指定选择器元素。"""
        ...

    def title(self) -> str:
        """返回页面标题。"""
        ...

    def inner_text(self, selector: str) -> str:
        """返回指定选择器的可见文本。"""
        ...

    def content(self) -> str:
        """返回页面 HTML 内容。"""
        ...

    def evaluate(self, expression: str, *args: Any, **kwargs: Any) -> Any:
        """执行页面 JavaScript 表达式。"""
        ...

    def screenshot(self, *args: Any, **kwargs: Any) -> bytes:
        """截取页面截图。"""
        ...

    def close(self) -> None:
        """关闭浏览器页面。"""
        ...


def launch_browser_context(headless: bool = True, **kwargs: Any) -> BrowserContext:
    """
    启动同步浏览器上下文；有界面模式先显式获取宿主显示资源。

    :param headless: 是否使用无头模式
    :param kwargs: 浏览器实现接受的其余启动参数
    :return: 浏览器上下文
    """
    if not headless:
        acquire_managed_resource(
            "host.display",
            reason="headed_browser_launch",
            retry=True,
        )
    from cloakbrowser import launch_context

    return launch_context(headless=headless, **kwargs)


async def launch_browser_context_async(
    headless: bool = True,
    **kwargs: Any,
) -> Any:
    """
    启动异步浏览器上下文；有界面模式等待宿主显示资源就绪。

    :param headless: 是否使用无头模式
    :param kwargs: 浏览器实现接受的其余启动参数
    :return: 浏览器上下文
    """
    if not headless:
        await acquire_managed_resource_async(
            "host.display",
            reason="headed_browser_launch",
            retry=True,
        )
    from cloakbrowser import launch_context_async

    return await launch_context_async(headless=headless, **kwargs)


@dataclass
class _BrowserSessionState:
    """保存一个可复用浏览器上下文及其页面游标。"""

    session_key: str
    context: BrowserContext
    pages: list[BrowserPage]
    active_index: int = 0
    user_agent: Optional[str] = None
    cookies: Optional[str] = None
    created_at: float = field(default_factory=time.monotonic)
    last_used_at: float = field(default_factory=time.monotonic)
    lock: threading.RLock = field(default_factory=threading.RLock)

    @property
    def active_page(self) -> BrowserPage:
        """返回会话当前选中的页面。"""
        return self.pages[self.active_index]


class BrowserSessionHelper:
    """
    Agent 浏览器会话辅助类，负责复用 CloakBrowser 上下文并生成可操作页面快照。
    """

    SESSION_TTL_SECONDS = 15 * 60
    MAX_SESSIONS = 8
    DEFAULT_VIEWPORT = {"width": 1280, "height": 720}
    PRIVATE_HOST_SUFFIXES = (".localhost", ".local", ".lan", ".home", ".internal")
    PRIVATE_HOSTNAMES = {"localhost", "ip6-localhost", "ip6-loopback"}
    REF_ATTRIBUTE = "data-moviepilot-agent-ref"
    SESSION_WORKER_NAME_PREFIX = "browser-session"

    _sessions: dict[str, _BrowserSessionState] = {}
    _session_executors: dict[str, ThreadPoolExecutor] = {}
    _session_thread_ids: dict[str, int] = {}
    _sessions_lock = threading.RLock()

    def __init__(self, headless: bool = True, viewport: Optional[dict[str, int]] = None):
        """
        初始化浏览器会话辅助类。

        :param headless: 是否使用无头浏览器
        :param viewport: 默认视口大小
        """
        self.headless = headless
        self.viewport = viewport or self.DEFAULT_VIEWPORT

    @classmethod
    def validate_url(cls, url: str, allow_private_network: bool = False) -> str:
        """
        校验浏览器可访问的 URL，默认拒绝本机、私网和非 HTTP 协议。

        :param url: 待访问的 URL
        :param allow_private_network: 是否允许访问本机或私网地址
        :return: 原始 URL
        """
        parsed = urlparse(url or "")
        if parsed.scheme not in {"http", "https"}:
            raise ValueError("仅支持 http/https URL")
        if not parsed.hostname:
            raise ValueError("URL 缺少主机名")

        hostname = parsed.hostname.lower().rstrip(".")
        if allow_private_network:
            return url

        if hostname in cls.PRIVATE_HOSTNAMES or hostname.endswith(
            cls.PRIVATE_HOST_SUFFIXES
        ):
            raise ValueError("默认不允许访问本机或私网地址")

        try:
            ip_address = ipaddress.ip_address(hostname)
        except ValueError:
            return url

        if not ip_address.is_global:
            raise ValueError("默认不允许访问本机或私网地址")
        return url

    @classmethod
    def ref_to_selector(cls, ref: str) -> str:
        """
        将页面快照中的元素引用转换为稳定选择器。

        :param ref: 快照返回的元素引用
        :return: 可传给浏览器的属性选择器
        """
        clean_ref = (ref or "").strip()
        if not clean_ref:
            raise ValueError("元素 ref 不能为空")
        escaped_ref = clean_ref.replace("\\", "\\\\").replace('"', '\\"')
        return f'[{cls.REF_ATTRIBUTE}="{escaped_ref}"]'

    @classmethod
    def close_all_sessions(cls) -> None:
        """
        关闭所有 Agent 浏览器会话。
        """
        with cls._sessions_lock:
            session_keys = list(
                set(cls._sessions.keys()) | set(cls._session_executors.keys())
            )
        for session_key in session_keys:
            cls.close_session(session_key)

    @classmethod
    def close_session(cls, session_key: str) -> bool:
        """
        关闭指定 Agent 浏览器会话。

        :param session_key: 会话标识
        :return: 找到并关闭会话时返回 True
        """
        if cls._is_current_session_thread(session_key):
            closed = cls._close_session_in_thread(session_key)
            cls._shutdown_session_executor(session_key, wait=False)
            return closed

        executor = cls._get_existing_session_executor(session_key)
        if executor:
            context = copy_context()
            # 会话线程保持空底层上下文，每次操作只使用当前调用快照。
            future = Context().run(
                executor.submit,
                context.run,
                cls._run_session_task,
                session_key,
                cls._close_session_in_thread,
                session_key,
            )
            try:
                return future.result()
            finally:
                cls._shutdown_session_executor(session_key)

        closed = cls._close_session_in_thread(session_key)
        cls._shutdown_session_executor(session_key)
        return closed

    def with_session(
        self,
        session_key: str,
        callback: Callable[[_BrowserSessionState], Any],
        user_agent: Optional[str] = None,
        cookies: Optional[str] = None,
        timeout: Optional[int] = 30,
    ) -> Any:
        """
        获取或创建浏览器会话，并在持有会话锁时执行回调。

        :param session_key: 会话标识
        :param callback: 使用浏览器会话执行操作的回调函数
        :param user_agent: 新建会话时使用的 User-Agent
        :param cookies: 本次操作要注入的 Cookie 请求头
        :param timeout: 默认操作超时时间，单位秒
        :return: 回调函数返回值
        """
        self._prune_sessions()
        return self._run_in_session_thread(
            session_key,
            self._with_session_in_thread,
            session_key,
            callback,
            user_agent=user_agent,
            cookies=cookies,
            timeout=timeout,
        )

    def _with_session_in_thread(
        self,
        session_key: str,
        callback: Callable[[_BrowserSessionState], Any],
        user_agent: Optional[str] = None,
        cookies: Optional[str] = None,
        timeout: Optional[int] = 30,
    ) -> Any:
        """
        在会话专属线程内获取浏览器会话并执行回调。

        :param session_key: 会话标识
        :param callback: 使用浏览器会话执行操作的回调函数
        :param user_agent: 新建会话时使用的 User-Agent
        :param cookies: 本次操作要注入的 Cookie 请求头
        :param timeout: 默认操作超时时间，单位秒
        :return: 回调函数返回值
        """
        session = self._get_or_create_session(
            session_key=session_key,
            user_agent=user_agent,
            cookies=cookies,
        )
        with session.lock:
            session.last_used_at = time.monotonic()
            if timeout and hasattr(session.active_page, "set_default_timeout"):
                session.active_page.set_default_timeout(int(timeout) * 1000)
            if cookies:
                session.cookies = cookies
                session.active_page.set_extra_http_headers({"cookie": cookies})
            return callback(session)

    @classmethod
    def _run_in_session_thread(
        cls,
        session_key: str,
        callback: Callable[..., Any],
        *args: Any,
        **kwargs: Any,
    ) -> Any:
        """
        将浏览器同步 API 调用投递到当前会话固定的单线程执行器。

        :param session_key: 会话标识
        :param callback: 需要在会话线程中运行的回调
        :param args: 回调位置参数
        :param kwargs: 回调关键字参数
        :return: 回调返回值
        """
        if cls._is_current_session_thread(session_key):
            return callback(*args, **kwargs)

        for _ in range(2):
            executor = cls._get_session_executor(session_key)
            try:
                context = copy_context()
                # 会话线程保持空底层上下文，每次操作只使用当前调用快照。
                future = Context().run(
                    executor.submit,
                    context.run,
                    cls._run_session_task,
                    session_key,
                    callback,
                    *args,
                    **kwargs,
                )
            except RuntimeError:
                cls._discard_session_executor(session_key, executor)
                continue
            try:
                return future.result()
            except Exception:
                with cls._sessions_lock:
                    has_session = session_key in cls._sessions
                if not has_session:
                    cls._shutdown_session_executor(session_key)
                raise

        raise RuntimeError("浏览器会话线程已关闭")

    @classmethod
    def _run_session_task(
        cls,
        session_key: str,
        callback: Callable[..., Any],
        *args: Any,
        **kwargs: Any,
    ) -> Any:
        """
        记录当前会话工作线程后执行实际任务。

        :param session_key: 会话标识
        :param callback: 需要执行的回调
        :param args: 回调位置参数
        :param kwargs: 回调关键字参数
        :return: 回调返回值
        """
        with cls._sessions_lock:
            cls._session_thread_ids[session_key] = threading.get_ident()
        return callback(*args, **kwargs)

    @classmethod
    def _is_current_session_thread(cls, session_key: str) -> bool:
        """
        判断当前代码是否已运行在指定会话的固定线程内。

        :param session_key: 会话标识
        :return: 当前线程是会话工作线程时返回 True
        """
        with cls._sessions_lock:
            thread_id = cls._session_thread_ids.get(session_key)
        return thread_id == threading.get_ident()

    @classmethod
    def _get_session_executor(cls, session_key: str) -> ThreadPoolExecutor:
        """
        获取或创建指定会话的单线程执行器。

        :param session_key: 会话标识
        :return: 会话专属执行器
        """
        with cls._sessions_lock:
            executor = cls._session_executors.get(session_key)
            if executor:
                return executor
            executor = ThreadPoolExecutor(
                max_workers=1,
                thread_name_prefix=cls.SESSION_WORKER_NAME_PREFIX,
            )
            cls._session_executors[session_key] = executor
            return executor

    @classmethod
    def _get_existing_session_executor(
        cls, session_key: str
    ) -> Optional[ThreadPoolExecutor]:
        """
        获取指定会话已存在的执行器。

        :param session_key: 会话标识
        :return: 已存在的执行器，不存在时返回 None
        """
        with cls._sessions_lock:
            return cls._session_executors.get(session_key)

    @classmethod
    def _discard_session_executor(
        cls,
        session_key: str,
        executor: ThreadPoolExecutor,
    ) -> None:
        """
        丢弃已经关闭的会话执行器。

        :param session_key: 会话标识
        :param executor: 需要从缓存中移除的执行器
        """
        with cls._sessions_lock:
            if cls._session_executors.get(session_key) is executor:
                cls._session_executors.pop(session_key, None)

    @classmethod
    def _shutdown_session_executor(
        cls,
        session_key: str,
        wait: bool = True,
    ) -> None:
        """
        关闭并移除指定会话的执行器。

        :param session_key: 会话标识
        :param wait: 是否等待工作线程退出
        """
        with cls._sessions_lock:
            executor = cls._session_executors.pop(session_key, None)
            cls._session_thread_ids.pop(session_key, None)
        if executor:
            executor.shutdown(wait=wait, cancel_futures=True)

    @classmethod
    def _close_session_in_thread(cls, session_key: str) -> bool:
        """
        在会话固定线程内关闭并移除浏览器会话。

        :param session_key: 会话标识
        :return: 找到并关闭会话时返回 True
        """
        with cls._sessions_lock:
            session = cls._sessions.pop(session_key, None)
        if not session:
            return False
        cls._close_session_state(session)
        return True

    def open_tab(
        self,
        session: _BrowserSessionState,
        url: Optional[str] = None,
        timeout: Optional[int] = 30,
        allow_private_network: bool = False,
    ) -> BrowserPage:
        """
        在当前会话中新建标签页，并可选导航到指定 URL。

        :param session: 当前浏览器会话
        :param url: 可选的目标 URL
        :param timeout: 导航超时时间，单位秒
        :param allow_private_network: 是否允许访问本机或私网地址
        :return: 新建的页面对象
        """
        page = session.context.new_page()
        if timeout and hasattr(page, "set_default_timeout"):
            page.set_default_timeout(int(timeout) * 1000)
        if session.cookies:
            page.set_extra_http_headers({"cookie": session.cookies})
        session.pages.append(page)
        session.active_index = len(session.pages) - 1
        if url:
            self.goto(
                page,
                url,
                timeout=timeout,
                allow_private_network=allow_private_network,
            )
        return page

    @staticmethod
    def list_tabs(session: _BrowserSessionState) -> list[dict[str, Any]]:
        """
        列出当前浏览器会话中的标签页。

        :param session: 当前浏览器会话
        :return: 标签页摘要列表
        """
        tabs = []
        for index, page in enumerate(session.pages):
            tabs.append(
                {
                    "index": index,
                    "active": index == session.active_index,
                    "url": getattr(page, "url", ""),
                    "title": BrowserSessionHelper._safe_page_title(page),
                }
            )
        return tabs

    @staticmethod
    def focus_tab(session: _BrowserSessionState, tab_index: int) -> BrowserPage:
        """
        切换当前会话的活动标签页。

        :param session: 当前浏览器会话
        :param tab_index: 标签页索引
        :return: 切换后的页面对象
        """
        if tab_index < 0 or tab_index >= len(session.pages):
            raise ValueError(f"标签页索引不存在: {tab_index}")
        session.active_index = tab_index
        return session.active_page

    @staticmethod
    def close_tab(session: _BrowserSessionState, tab_index: int) -> list[dict[str, Any]]:
        """
        关闭当前会话中的指定标签页。

        :param session: 当前浏览器会话
        :param tab_index: 标签页索引
        :return: 关闭后的标签页列表
        """
        if tab_index < 0 or tab_index >= len(session.pages):
            raise ValueError(f"标签页索引不存在: {tab_index}")
        page = session.pages.pop(tab_index)
        try:
            page.close()
        except Exception as err:
            logger.warning(f"关闭浏览器标签页失败: {str(err)}")
        if not session.pages:
            session.pages.append(session.context.new_page())
        session.active_index = min(session.active_index, len(session.pages) - 1)
        return BrowserSessionHelper.list_tabs(session)

    def goto(
        self,
        page: BrowserPage,
        url: str,
        timeout: Optional[int] = 30,
        allow_private_network: bool = False,
    ) -> Any:
        """
        校验并导航页面到指定 URL。

        :param page: 页面对象
        :param url: 目标 URL
        :param timeout: 导航超时时间，单位秒
        :param allow_private_network: 是否允许访问本机或私网地址
        :return: 浏览器导航响应对象
        """
        self.validate_url(url, allow_private_network=allow_private_network)
        response = page.goto(
            url,
            wait_until="domcontentloaded",
            timeout=int(timeout or 30) * 1000,
        )
        try:
            page.wait_for_load_state(
                "networkidle",
                timeout=min(int(timeout or 30), 15) * 1000,
            )
        except Exception:
            pass
        self.validate_current_url(page, allow_private_network=allow_private_network)
        return response

    @classmethod
    def validate_current_url(
        cls, page: BrowserPage, allow_private_network: bool = False
    ) -> None:
        """
        校验当前页面地址，捕获跳转后的不安全目标。

        :param page: 页面对象
        :param allow_private_network: 是否允许访问本机或私网地址
        """
        current_url = getattr(page, "url", "")
        if current_url and current_url.startswith(("http://", "https://")):
            cls.validate_url(current_url, allow_private_network=allow_private_network)

    @classmethod
    def build_snapshot(
        cls,
        page: BrowserPage,
        status: Optional[Any] = None,
        max_text_chars: int = 8000,
        max_elements: int = 40,
    ) -> dict[str, Any]:
        """
        构建包含可读文本和可交互元素 ref 的页面快照。

        :param page: 页面对象
        :param status: 可选的导航状态码
        :param max_text_chars: 页面文本最大返回长度
        :param max_elements: 最大可交互元素数量
        :return: 页面快照字典
        """
        text_content = cls._safe_inner_text(page, "body")
        result = {
            "url": getattr(page, "url", ""),
            "title": cls._safe_page_title(page),
            "text_content": cls._truncate_text(text_content, max_text_chars),
            "interactive_elements": cls._extract_interactive_elements(
                page, max_elements=max_elements
            ),
        }
        if status is not None:
            result["status"] = status

        links = [
            {
                "ref": element.get("ref"),
                "text": element.get("text"),
                "href": element.get("href"),
            }
            for element in result["interactive_elements"]
            if element.get("tag") == "a" and element.get("href")
        ][:30]
        forms = [
            element
            for element in result["interactive_elements"]
            if element.get("tag") in {"input", "textarea", "select", "button"}
        ][:30]
        if links:
            result["links"] = links
        if forms:
            result["form_elements"] = forms
        return result

    @staticmethod
    def _launch_context(
        headless: bool,
        user_agent: Optional[str] = None,
        viewport: Optional[dict[str, int]] = None,
    ) -> BrowserContext:
        """按宿主反检测配置创建 CloakBrowser 上下文。"""
        context_kwargs = {
            "humanize": settings.CLOAKBROWSER_HUMANIZE,
            "human_preset": settings.CLOAKBROWSER_HUMAN_PRESET,
        }
        if user_agent:
            context_kwargs["user_agent"] = user_agent
        if viewport:
            context_kwargs["viewport"] = viewport
        return launch_browser_context(headless=headless, **context_kwargs)

    def _get_or_create_session(
        self,
        session_key: str,
        user_agent: Optional[str] = None,
        cookies: Optional[str] = None,
    ) -> _BrowserSessionState:
        """复用匹配会话，或为新的会话键创建上下文。"""
        with self._sessions_lock:
            session = self._sessions.get(session_key)
            if session and user_agent and session.user_agent != user_agent:
                self._sessions.pop(session_key, None)
                self._close_session_state(session)
                session = None
            if session:
                return session

        context = self._launch_context(
            headless=self.headless,
            user_agent=user_agent,
            viewport=self.viewport,
        )
        page = context.new_page()
        if cookies:
            page.set_extra_http_headers({"cookie": cookies})
        session = _BrowserSessionState(
            session_key=session_key,
            context=context,
            pages=[page],
            user_agent=user_agent,
            cookies=cookies,
        )
        with self._sessions_lock:
            existing_session = self._sessions.get(session_key)
            if existing_session:
                self._close_session_state(session)
                return existing_session
            self._sessions[session_key] = session
        self._enforce_session_limit(protect_session_key=session_key)
        return session

    @classmethod
    def _prune_sessions(cls) -> None:
        """关闭超过空闲时限的浏览器会话。"""
        now = time.monotonic()
        with cls._sessions_lock:
            expired_keys = [
                session_key
                for session_key, session in cls._sessions.items()
                if now - session.last_used_at > cls.SESSION_TTL_SECONDS
            ]
        for session_key in expired_keys:
            cls.close_session(session_key)

    @classmethod
    def _enforce_session_limit(cls, protect_session_key: Optional[str] = None) -> None:
        """
        清理超过数量上限的旧会话。

        :param protect_session_key: 本次刚创建、需要优先保留的会话标识
        """
        while True:
            with cls._sessions_lock:
                if len(cls._sessions) <= cls.MAX_SESSIONS:
                    return
                candidate_keys = [
                    session_key
                    for session_key in cls._sessions
                    if session_key != protect_session_key
                ]
                if not candidate_keys:
                    return
                oldest_key = min(
                    candidate_keys,
                    key=lambda key: cls._sessions[key].last_used_at,
                )
            if not cls.close_session(oldest_key):
                return

    @staticmethod
    def _close_session_state(session: _BrowserSessionState) -> None:
        """尽力关闭会话中的全部页面和浏览器上下文。"""
        with session.lock:
            for page in list(session.pages):
                try:
                    page.close()
                except Exception as err:
                    logger.warning(f"关闭浏览器页面失败: {str(err)}")
            try:
                session.context.close()
            except Exception as err:
                logger.warning(f"关闭浏览器上下文失败: {str(err)}")

    @staticmethod
    def _safe_page_title(page: BrowserPage) -> str:
        """读取页面标题，页面失效时返回空字符串。"""
        try:
            return page.title()
        except Exception:
            return ""

    @staticmethod
    def _safe_inner_text(page: BrowserPage, selector: str) -> str:
        """读取节点文本，选择器或页面失效时返回空字符串。"""
        try:
            return page.inner_text(selector)
        except Exception:
            return ""

    @staticmethod
    def _truncate_text(text: Optional[str], max_chars: int) -> str:
        """按 Agent 上下文上限截断页面文本。"""
        if not text:
            return ""
        if len(text) <= max_chars:
            return text
        return text[:max_chars] + "\n\n...(内容已截断)"

    @classmethod
    def _extract_interactive_elements(
        cls, page: BrowserPage, max_elements: int
    ) -> list[dict[str, Any]]:
        """提取页面中可见且可交互的元素快照。"""
        script = f"""
            () => {{
                const limit = {int(max_elements)};
                const selector = [
                    'a[href]',
                    'button',
                    'input',
                    'textarea',
                    'select',
                    '[role="button"]',
                    '[role="link"]',
                    '[onclick]',
                    'summary'
                ].join(',');
                const isVisible = (el) => {{
                    const style = window.getComputedStyle(el);
                    const rect = el.getBoundingClientRect();
                    return style && style.visibility !== 'hidden'
                        && style.display !== 'none'
                        && rect.width > 0
                        && rect.height > 0;
                }};
                return Array.from(document.querySelectorAll(selector))
                    .filter(isVisible)
                    .slice(0, limit)
                    .map((el, index) => {{
                        const ref = `e${{index + 1}}`;
                        el.setAttribute('{cls.REF_ATTRIBUTE}', ref);
                        const tag = el.tagName.toLowerCase();
                        const text = (
                            el.innerText
                            || el.value
                            || el.getAttribute('aria-label')
                            || el.getAttribute('title')
                            || el.getAttribute('placeholder')
                            || ''
                        ).trim();
                        return {{
                            ref,
                            tag,
                            type: el.type || '',
                            text: text.substring(0, 120),
                            name: el.name || '',
                            id: el.id || '',
                            role: el.getAttribute('role') || '',
                            placeholder: el.getAttribute('placeholder') || '',
                            href: el.href || '',
                            value: tag === 'select' ? '' : (el.value || '').substring(0, 80),
                            selector: `[${cls.REF_ATTRIBUTE}="${{ref}}"]`
                        }};
                    }});
            }}
        """
        try:
            elements = page.evaluate(script)
        except Exception as err:
            logger.debug(f"提取页面可交互元素失败: {str(err)}")
            return []
        if not isinstance(elements, list):
            return []
        return elements


class PlaywrightHelper:
    """为旧插件浏览器调用提供统一的 CloakBrowser 适配。"""

    def __init__(self, browser_type: Optional[str] = None, *args, **kwargs):
        """
        兼容旧的 PlaywrightHelper(browser_type=...) 构造方式。
        """
        self.browser_type = browser_type or settings.PLAYWRIGHT_BROWSER_TYPE

    @staticmethod
    def __browser_emulation() -> str:
        """
        当前浏览器仿真类型。
        """
        return (settings.BROWSER_EMULATION or "cloakbrowser").lower()

    @staticmethod
    def __launch_cloakbrowser_context(headless: bool,
                                      user_agent: Optional[str] = None,
                                      proxies: Optional[dict] = None) -> BrowserContext:
        """
        启动 CloakBrowser 上下文。
        """
        return launch_browser_context(headless=headless,
                                      proxy=proxies,
                                      user_agent=user_agent,
                                      humanize=settings.CLOAKBROWSER_HUMANIZE,
                                      human_preset=settings.CLOAKBROWSER_HUMAN_PRESET)

    @staticmethod
    def __fs_cookie_str(cookies: list) -> str:
        """将 FlareSolverr Cookie 列表转换为请求头字符串。"""
        if not cookies:
            return ""
        return "; ".join([f"{c.get('name')}={c.get('value')}" for c in cookies if c and c.get('name') is not None])

    @staticmethod
    def __flaresolverr_request(url: str,
                               cookies: Optional[str] = None,
                               proxy_config: Optional[dict] = None,
                               timeout: Optional[int] = 60) -> Optional[dict]:
        """
        调用 FlareSolverr 解决 Cloudflare 并返回 solution 结果
        参考: https://github.com/FlareSolverr/FlareSolverr
        """
        if not settings.FLARESOLVERR_URL:
            logger.warn("未配置 FLARESOLVERR_URL，无法使用 FlareSolverr")
            return None

        fs_api = settings.FLARESOLVERR_URL.rstrip("/") + "/v1"
        session_id = None

        try:
            # 检查是否需要代理认证
            need_proxy_auth = (proxy_config and proxy_config.get("server") and
                               (proxy_config.get("username") or proxy_config.get("password")))

            if need_proxy_auth:
                # 使用 session 模式支持代理认证
                logger.debug("检测到flaresolverr代理需要认证，使用 session 模式")

                # 1. 创建会话
                session_id = str(uuid.uuid4())
                create_payload: dict = {
                    "cmd": "sessions.create",
                    "session": session_id
                }

                # 添加代理配置到会话创建请求
                if proxy_config and proxy_config.get("server"):
                    proxy_payload: dict = {"url": proxy_config["server"]}
                    if proxy_config.get("username"):
                        proxy_payload["username"] = proxy_config["username"]
                    if proxy_config.get("password"):
                        proxy_payload["password"] = proxy_config["password"]
                    create_payload["proxy"] = proxy_payload

                # 创建会话
                create_result = RequestUtils(content_type="application/json",
                                             timeout=timeout or 60).post_json(url=fs_api, json=create_payload)
                if not create_result or create_result.get("status") != "ok":
                    logger.error(
                        f"创建 FlareSolverr 会话失败: {create_result.get('message') if create_result else '无响应'}")
                    return None

                # 2. 使用会话发送请求
                request_payload = {
                    "cmd": "request.get",
                    "url": url,
                    "session": session_id,
                    "maxTimeout": int(timeout or 60) * 1000,
                }
            else:
                # 使用普通模式（无代理认证）
                request_payload = {
                    "cmd": "request.get",
                    "url": url,
                    "maxTimeout": int(timeout or 60) * 1000,
                }
                # 添加代理配置（仅 URL，无认证）
                if proxy_config and proxy_config.get("server"):
                    request_payload["proxy"] = {"url": proxy_config["server"]}

            # 将 cookies 以数组形式传递给 FlareSolverr
            if cookies:
                try:
                    request_payload["cookies"] = cookie_parse(cookies, array=True)
                except Exception as e:
                    logger.debug(f"解析 cookies 失败，忽略: {str(e)}")

            # 发送请求
            data = RequestUtils(content_type="application/json",
                                timeout=timeout or 60).post_json(url=fs_api, json=request_payload)
            if not data:
                logger.error("FlareSolverr 返回空响应")
                return None
            if data.get("status") != "ok":
                logger.error(f"FlareSolverr 调用失败: {data.get('message')}")
                return None
            return data.get("solution")
        except Exception as e:
            logger.error(f"调用 FlareSolverr 失败: {str(e)}")
            return None
        finally:
            # 清理会话
            if session_id:
                try:
                    destroy_payload = {
                        "cmd": "sessions.destroy",
                        "session": session_id
                    }
                    RequestUtils(content_type="application/json",
                                 timeout=10).post_json(url=fs_api, json=destroy_payload)
                    logger.debug(f"已清理 FlareSolverr 会话: {session_id}")
                except Exception as e:
                    logger.warning(f"清理 FlareSolverr 会话失败: {str(e)}")

    def action(self, url: str,
               callback: Callable[[BrowserPage], Any],
               cookies: Optional[str] = None,
               ua: Optional[str] = None,
               proxies: Optional[dict] = None,
               headless: Optional[bool] = False,
               timeout: Optional[int] = 60) -> Any:
        """
        访问网页，接收Page对象并执行操作
        :param url: 网页地址
        :param callback: 回调函数，需要接收page对象
        :param cookies: cookies
        :param ua: user-agent
        :param proxies: 代理
        :param headless: 是否无头模式
        :param timeout: 超时时间
        """
        result = None
        try:
            context = None
            page = None
            try:
                # 如果配置使用 FlareSolverr，先通过其获取清除后的 cookies 与 UA
                fs_cookie_header = None
                fs_ua = None
                if self.__browser_emulation() == "flaresolverr":
                    solution = self.__flaresolverr_request(url=url, cookies=cookies,
                                                           proxy_config=proxies, timeout=timeout)
                    if solution:
                        fs_cookie_header = self.__fs_cookie_str(solution.get("cookies", []))
                        fs_ua = solution.get("userAgent")

                context = self.__launch_cloakbrowser_context(headless=headless,
                                                             user_agent=fs_ua or ua,
                                                             proxies=proxies)
                page = context.new_page()

                # 优先使用 FlareSolverr 返回，其次使用入参
                merged_cookie = fs_cookie_header or cookies
                if merged_cookie:
                    page.set_extra_http_headers({"cookie": merged_cookie})

                page.goto(url)
                page.wait_for_load_state("networkidle", timeout=timeout * 1000)

                # 回调函数
                result = callback(page)

            except Exception as e:
                logger.error(f"网页操作失败: {str(e)}")
            finally:
                if page:
                    page.close()
                if context:
                    context.close()
        except Exception as e:
            logger.error(f"CloakBrowser初始化失败: {str(e)}")

        return result

    def get_page_source(self, url: str,
                        cookies: Optional[str] = None,
                        ua: Optional[str] = None,
                        proxies: Optional[dict] = None,
                        headless: Optional[bool] = False,
                        timeout: Optional[int] = 60) -> Optional[str]:
        """
        获取网页源码
        :param url: 网页地址
        :param cookies: cookies
        :param ua: user-agent
        :param proxies: 代理
        :param headless: 是否无头模式
        :param timeout: 超时时间
        """
        timeout = timeout or 60
        source = None
        # 如果配置为 FlareSolverr，则直接调用获取页面源码
        if self.__browser_emulation() == "flaresolverr":
            try:
                solution = self.__flaresolverr_request(url=url, cookies=cookies,
                                                       proxy_config=proxies, timeout=timeout)
                if solution:
                    return solution.get("response")
            except Exception as e:
                logger.error(f"FlareSolverr 获取源码失败: {str(e)}")
        try:
            context = None
            page = None
            try:
                context = self.__launch_cloakbrowser_context(headless=headless,
                                                             user_agent=ua,
                                                             proxies=proxies)
                page = context.new_page()

                if cookies:
                    page.set_extra_http_headers({"cookie": cookies})

                page.goto(url, wait_until="load", timeout=timeout * 1000)

                # 修复: 部分站点(如 Cloudflare 质询页)会持续轮询请求,
                # 导致 networkidle 永不触发而超时。改为等待页面加载完成后
                # 轮询检查标题, 直到不再停留在质询/加载页。
                challenge_titles = ("just a moment", "请稍候", "loading")
                deadline = time.time() + timeout
                while time.time() < deadline:
                    try:
                        current_title = (page.title() or "").strip().lower()
                    except Exception:
                        current_title = ""
                    if current_title and not any(
                            t in current_title for t in challenge_titles):
                        break
                    time.sleep(2)

                # 页面跳转中 content() 可能失败, 重试几次
                source = None
                for _attempt in range(5):
                    try:
                        source = page.content()
                        if source:
                            break
                    except Exception:
                        source = None
                        time.sleep(2)

            except Exception as e:
                logger.error(f"获取网页源码失败: {str(e)}")
                source = None
            finally:
                # 确保资源被正确清理
                if page:
                    page.close()
                if context:
                    context.close()
        except Exception as e:
            logger.error(f"CloakBrowser初始化失败: {str(e)}")

        return source