#!/usr/bin/env python3
"""
第一步：检测 CDP 远程调试端口是否已有浏览器（``cdp_endpoint_open`` + ``/json/version``）；
已开启则只附着、不新启 Chrome；否则再按 browser_core 逻辑连接或拉起调试实例。
若已是 HOME_URL，则 **不 goto**。默认同站且非空白时也不跳转（保留当前子路径，如搜索结果页）；主流程可将 ``same_site_preserves_current_page=False`` 以始终打开 ``home_url``；若同时 ``skip_home_navigation_when_top_search_input_has_text=True``，则顶栏搜索框已有文案时 **不** 先刷新主页，交给 ``clear-input``。仅空白页或（在允许时）跨站时导航到 ``home_url``。
"""

from __future__ import annotations

import sys
import urllib.request
from collections.abc import Callable
from pathlib import Path
from typing import Any, TypeVar
from urllib.parse import urlparse

_ROOT = Path(__file__).resolve().parent.parent
if str(_ROOT) not in sys.path:
    sys.path.insert(0, str(_ROOT))

from workplace.cdp_chrome_browser_core import cdp_endpoint_open  # noqa: E402
from workplace.playwright import (  # noqa: E402
    DEFAULT_CDP_URL,
    _is_blank_url,
    connect_browser_via_cdp,
    pick_target_page,
    sync_playwright,
)

_T = TypeVar("_T")

_HOME_PAGE_DOCUMENT_LOAD_WAIT_TIMEOUT_MILLISECONDS = 20_000

# 与 ``workplace/input-keyword/find_search_input.py`` 中顶栏搜索框一致（用于判断是否已有文案、避免先 goto 冲掉）。
_TOP_BAR_SEARCH_INPUT_SELECTOR = "#search-input"


def _top_search_input_has_non_empty_text(page: Any) -> bool:
    """当前页存在顶栏 ``#search-input`` 且 ``input_value`` 去空白后非空时返回 True；否则 False。"""
    try:
        locator = page.locator(_TOP_BAR_SEARCH_INPUT_SELECTOR).first
        if locator.count() == 0:
            return False
        raw = str(locator.input_value(timeout=3_000)).strip()
        return bool(raw)
    except Exception:
        return False


def _wait_current_page_document_load_completed_or_raise_error(page) -> None:
    page.wait_for_load_state(
        "load",
        timeout=_HOME_PAGE_DOCUMENT_LOAD_WAIT_TIMEOUT_MILLISECONDS,
    )


def _path_key(path: str | None) -> str:
    p = (path or "").strip() or "/"
    p = p.rstrip("/")
    return "" if p in ("", "/") else p


def _maximize_chrome_main_window_and_bring_to_foreground_win32(page) -> None:
    """
    Windows：把 Chrome 主窗口**最大化**（工作区铺满，非 F11 全屏）并置于前台。
    若已最小化则一并拉起。Playwright 的 ``bring_to_front`` 只作用于页签层。
    """
    if sys.platform != "win32":
        return
    try:
        tab_title = (page.title() or "").strip()
    except Exception:
        tab_title = ""

    import ctypes
    from ctypes import wintypes

    user32 = ctypes.windll.user32
    SW_MAXIMIZE = 3
    candidates: list[tuple[int, str, int]] = []

    @ctypes.WINFUNCTYPE(ctypes.c_bool, wintypes.HWND, wintypes.LPARAM)
    def enum_proc(hwnd, _lparam):
        if not user32.IsWindowVisible(hwnd):
            return True
        cls = ctypes.create_unicode_buffer(256)
        user32.GetClassNameW(hwnd, cls, 256)
        if cls.value != "Chrome_WidgetWin_1":
            return True
        ln = user32.GetWindowTextLengthW(hwnd)
        if ln <= 0:
            return True
        buf = ctypes.create_unicode_buffer(ln + 1)
        user32.GetWindowTextW(hwnd, buf, ln + 1)
        title = buf.value
        if not title:
            return True
        rect = wintypes.RECT()
        if not user32.GetWindowRect(hwnd, ctypes.byref(rect)):
            return True
        w = max(0, rect.right - rect.left)
        h = max(0, rect.bottom - rect.top)
        if w * h < 80_000:
            return True
        candidates.append((int(hwnd), title, w * h))
        return True

    user32.EnumWindows(enum_proc, 0)
    if not candidates:
        return

    def score(item: tuple[int, str, int]) -> int:
        _hwnd, title, area = item
        s = min(area // 500, 8000)
        if tab_title:
            if tab_title in title:
                s += 50_000
            elif len(tab_title) >= 4 and tab_title[:12] in title:
                s += 25_000
        if "Chrome" in title or "chrome" in title.lower():
            s += 100
        return s

    hwnd = max(candidates, key=score)[0]
    try:
        user32.ShowWindow(hwnd, SW_MAXIMIZE)
        user32.SetForegroundWindow(hwnd)
    except Exception:
        pass


def _chrome_remote_debugging_http_endpoint_ready(cdp_browser_http_url: str) -> bool:
    """
    若 Chrome 已在该地址开启远程调试，``GET …/json/version`` 通常返回 200。
    作为 ``cdp_endpoint_open`` 的补充，避免误判后再次 ``auto_chrome`` 拉起第二个实例。
    """
    raw = (cdp_browser_http_url or "").strip()
    if not raw:
        return False
    parsed = urlparse(raw)
    if not parsed.hostname:
        return False
    scheme = (parsed.scheme or "http").lower()
    port = parsed.port
    if port is None:
        port = 443 if scheme == "https" else 80
    version_probe_url = f"{scheme}://{parsed.hostname}:{port}/json/version"
    try:
        with urllib.request.urlopen(version_probe_url, timeout=2.0) as http_response:
            return http_response.status == 200
    except Exception:
        return False


def _same_page_as_home(current: str, home: str) -> bool:
    h = (home or "").strip()
    if not h:
        return False
    c = (current or "").strip()
    if not c.startswith("http"):
        return False
    a = urlparse(c)
    b = urlparse(h)
    return (
        a.scheme.lower() == b.scheme.lower()
        and a.netloc.lower() == b.netloc.lower()
        and _path_key(a.path) == _path_key(b.path)
        and (a.query or "") == (b.query or "")
    )


def _same_site_as_home_not_blank(current: str, home: str) -> bool:
    """与 ``home_url`` 同 host、且当前不是空白页 — 候选「可跳过 goto」的前置条件。"""
    h = (home or "").strip()
    if not h.startswith("http"):
        return False
    c = (current or "").strip()
    if not c.startswith("http") or _is_blank_url(c):
        return False
    return urlparse(c).netloc.lower() == urlparse(h).netloc.lower()


def prepare_page_at_home_url(
    playwright_inst,
    home_url: str,
    *,
    cdp: str | None = None,
    same_site_preserves_current_page: bool = True,
    skip_home_navigation_when_top_search_input_has_text: bool = False,
):
    """
    在调用方已有的 ``with sync_playwright() as p:`` 里执行：附着 CDP、选页；按规则 ``goto`` 到 ``home_url``。

    ``same_site_preserves_current_page``：为 ``True``（默认）时，若当前已是小红书同站且非空白，则 **不** 导航，以免冲掉已有搜索结果等；主流程入口宜传 ``False``，保证打开配置中的主页 URL。

    ``skip_home_navigation_when_top_search_input_has_text``：为 ``True`` 时，若已附着到小红书同站页且顶栏 ``#search-input`` 内已有文案，则 **不** 先 ``goto`` 主页，保留当前页，由 ``input-keyword`` 里 ``clear-input`` 清空后再输入（供 ``start.bat`` 第二轮关键词等场景）。

    返回 ``(退出码, page | None)``。成功时 ``page`` 仍绑定当前浏览器上下文，勿在 ``with`` 块外长期使用。
    """
    home_url = (home_url or "").strip()
    if not home_url.startswith("http"):
        print("Invalid HOME_URL.", file=sys.stderr)
        return 1, None

    url = (cdp or "").strip() or DEFAULT_CDP_URL
    debugging_endpoint_already_listening = cdp_endpoint_open(url) or (
        _chrome_remote_debugging_http_endpoint_ready(url)
    )
    if debugging_endpoint_already_listening:
        print("检测到远程调试端口已有浏览器，仅附着、不新启 Chrome:", url, file=sys.stderr)
    else:
        print(
            f"未检测到调试端口监听，将连接并在需要时启动调试 Chrome：{url}",
            file=sys.stderr,
        )

    try:
        browser = connect_browser_via_cdp(
            playwright_inst,
            cdp=url,
            auto_chrome=not debugging_endpoint_already_listening,
        )
    except Exception as e:
        print("CDP connect failed:", e, file=sys.stderr)
        return 1, None

    page = pick_target_page(browser)
    if not page:
        print("No browser page available.", file=sys.stderr)
        return 1, None
    try:
        page.bring_to_front()
    except Exception:
        pass
    _maximize_chrome_main_window_and_bring_to_foreground_win32(page)

    url_now = (page.url or "").strip()
    if _is_blank_url(url_now):
        print("Blank tab — opening HOME_URL:", home_url, file=sys.stderr)
        page.goto(
            home_url,
            wait_until="load",
            timeout=_HOME_PAGE_DOCUMENT_LOAD_WAIT_TIMEOUT_MILLISECONDS,
        )
        return 0, page

    if _same_page_as_home(url_now, home_url):
        print("已在 HOME_URL，跳过导航。", file=sys.stderr)
        _wait_current_page_document_load_completed_or_raise_error(page)
        return 0, page

    if (
        same_site_preserves_current_page
        and _same_site_as_home_not_blank(url_now, home_url)
    ):
        print("同站已打开，跳过导航与刷新:", url_now, file=sys.stderr)
        _wait_current_page_document_load_completed_or_raise_error(page)
        return 0, page

    if (
        skip_home_navigation_when_top_search_input_has_text
        and _same_site_as_home_not_blank(url_now, home_url)
        and _top_search_input_has_non_empty_text(page)
    ):
        print(
            "顶栏搜索框已有文案，保留当前页（不先刷新主页），随后由 clear-input 清空。",
            file=sys.stderr,
        )
        _wait_current_page_document_load_completed_or_raise_error(page)
        return 0, page

    print("导航到 HOME_URL:", home_url, file=sys.stderr)
    page.goto(
        home_url,
        wait_until="load",
        timeout=_HOME_PAGE_DOCUMENT_LOAD_WAIT_TIMEOUT_MILLISECONDS,
    )
    return 0, page


def prepare_page_at_home_url_then(
    playwright_inst,
    home_url: str,
    then: Callable[[Any], _T],
    *,
    cdp: str | None = None,
    same_site_preserves_current_page: bool = True,
    skip_home_navigation_when_top_search_input_has_text: bool = False,
) -> _T:
    """
    ``prepare_page_at_home_url`` 成功后把 ``page`` 交给 ``then``；失败则抛错（不返回 (code, page)）。
    ``then`` 签名为 ``(page) -> T``。
    """
    code, page = prepare_page_at_home_url(
        playwright_inst,
        home_url,
        cdp=cdp,
        same_site_preserves_current_page=same_site_preserves_current_page,
        skip_home_navigation_when_top_search_input_has_text=skip_home_navigation_when_top_search_input_has_text,
    )
    if code != 0 or page is None:
        raise RuntimeError(f"prepare_page_at_home_url failed: code={code}")
    return then(page)


def start(
    playwright_inst,
    home_url: str,
    then: Callable[[Any], _T],
    *,
    cdp: str | None = None,
    same_site_preserves_current_page: bool = True,
    skip_home_navigation_when_top_search_input_has_text: bool = False,
) -> _T:
    """
    附着 CDP；仅在需要时 ``goto``（见 ``prepare_page_at_home_url``）。
    不在此重复 ``wait_for_load_state``，避免同页再次等待或体感上的刷新。

    ``then`` 签名为 ``(page) -> T``；失败在 ``prepare`` 阶段抛 ``RuntimeError``。
    """

    def _after_browser_and_navigation_ready(page: Any) -> _T:
        return then(page)

    return prepare_page_at_home_url_then(
        playwright_inst,
        home_url,
        _after_browser_and_navigation_ready,
        cdp=cdp,
        same_site_preserves_current_page=same_site_preserves_current_page,
        skip_home_navigation_when_top_search_input_has_text=skip_home_navigation_when_top_search_input_has_text,
    )


def ensure_browser_on_home_url(
    home_url: str,
    *,
    cdp: str | None = None,
    same_site_preserves_current_page: bool = True,
    skip_home_navigation_when_top_search_input_has_text: bool = False,
) -> tuple[int, str | None]:
    """
    附着 Chrome CDP；选取目标页。
    - 空白页：goto home_url
    - 已是 HOME_URL：跳过导航
    - 与 home 同站且非空白：跳过导航（含搜索结果页等，不强制回首页）
    - 其它（跨站等）：goto home_url

    若 CDP 端口已在监听，视为浏览器已开启调试，仅附着且 **不再** 自动拉起第二个 Chrome；
    未监听时再 ``connect_browser_via_cdp(..., auto_chrome=True)`` 尝试启动调试实例。

    成功时返回 ``(0, html)``，``html`` 为当前页 ``page.content()``；失败时 ``(非0, None)``。

    Windows 下会在附着后把 **Chrome 主窗口最大化** 并置于前台（便于后续 PyAutoGUI 等）。
    """
    with sync_playwright() as p:
        code, page = prepare_page_at_home_url(
            p,
            home_url,
            cdp=cdp,
            same_site_preserves_current_page=same_site_preserves_current_page,
            skip_home_navigation_when_top_search_input_has_text=skip_home_navigation_when_top_search_input_has_text,
        )
        if code != 0 or page is None:
            return code, None
        try:
            return 0, page.content()
        except Exception:
            return 1, None