/**
 * 通用 spider 站点适配器(NexusPHP 等 HTML 站)。
 *
 * 对应 MoviePilot e6820a8:
 * - `app/modules/indexer/__init__.py IndexerModule.search_torrents / refresh_torrents` → `search` / `list`
 *   (`__search_check` 的英文站不搜中文 → search 前检查;`__clear_search_text` → `clearSearchText`;
 *    `SitesHelper.check(domain)` 流控 → 站点令牌桶)
 * - `SiteSpider.get_torrents`(RequestUtils GET + cookie + ua)→ `fetchPage`
 * - `app/chain/download/submission.py download_torrent`(带 cookie GET enclosure,磁力原样返回)→ `downloadTarget`
 *
 * 本项目调整:登录页不再"返回空列表",而是抛 `auth_expired`(REQ §4.7.1 不展示空列表冒充无内容);
 * 3xx 不自动跟随(避免把 cookie 带到站外,并把跳转 login 识别为失效);凭证经 SecretResolver 注入。
 */
import { redactText } from "../../rss/redact.ts";
import { buildHttpContext, type SiteAdapterDeps } from "../deps.ts";
import { readBody, readText, siteFetch } from "../http.ts";
import {
  type DownloadTarget,
  type SiteAdapter,
  type SiteCallOptions,
  SiteError,
  type SiteHealth,
  type SiteListFilters,
  type SitePage,
  type SiteReleaseDetail,
} from "../types.ts";
import { inspectTorrent } from "../util.ts";
import { parseDetailPage } from "./detail.ts";
import { filesFromFileListHtml } from "./detail-page.ts";
import { spiderTorrentToRelease } from "./map.ts";
import type { IndexerDefinition } from "./schema.ts";
import { loadHtml, normalizeSelector, SiteSpider } from "./spider.ts";

/** MP `text_tools.remove_punctuation(text, replacement=" ", allow_space=True)` */
export function clearSearchText(text: string): string {
  return text
    .replace(/[​-‍]/g, "")
    .replace(/[、.。,，·:：;；!！?？'’"“”()（）[\]【】「」\-—―+|\\_/&#～~]/g, " ")
    .replace(/\s+/g, " ")
    .trim();
}

function containsChinese(s: string): boolean {
  return /[一-鿿]/.test(s);
}

export function healthFromError(siteId: string, e: unknown, checkedAt: string): SiteHealth {
  if (e instanceof SiteError) {
    const status: SiteHealth["status"] =
      e.kind === "network"
        ? "unreachable"
        : e.kind === "not_found" || e.kind === "unsupported"
          ? "parse_error"
          : e.kind;
    return { siteId, status, ok: false, checkedAt, latencyMs: null, message: e.message };
  }
  return { siteId, status: "unreachable", ok: false, checkedAt, latencyMs: null, message: redactText(String(e)) };
}

export function createSpiderSiteAdapter(input: IndexerDefinition, deps: SiteAdapterDeps): SiteAdapter {
  const def: IndexerDefinition = deps.baseUrl ? { ...input, domain: deps.baseUrl } : input;
  const ext = def.umt;
  const http = buildHttpContext(def.id, deps, ext.rateLimit);
  const base = def.domain.endsWith("/") ? def.domain : `${def.domain}/`;

  async function cookie(): Promise<string> {
    const c = await deps.secrets.resolve({ siteId: def.id, kind: "cookie" });
    if (!c) throw new SiteError(def.id, "auth_missing", "未配置站点 Cookie");
    return c;
  }

  async function fetchPage(url: string, what: string, opts: SiteCallOptions): Promise<string> {
    const res = await siteFetch(http, url, {
      method: "GET",
      headers: { cookie: await cookie(), accept: "text/html,application/xhtml+xml", referer: base },
      redirect: "manual",
      ...(opts.signal ? { signal: opts.signal } : {}),
    });
    if (res.status >= 300 && res.status < 400) {
      const loc = res.headers.get("location") ?? "";
      await res.body?.cancel().catch(() => {});
      if (/login/i.test(loc)) throw new SiteError(def.id, "auth_expired", `${what}:跳转登录页,Cookie 已失效`);
      throw new SiteError(def.id, "parse_error", redactText(`${what}:意外重定向到 ${loc}`), { httpStatus: res.status });
    }
    if (res.status === 401 || res.status === 403) {
      await res.body?.cancel().catch(() => {});
      throw new SiteError(def.id, "auth_invalid", `${what}:HTTP ${res.status}`, { httpStatus: res.status });
    }
    if (!res.ok) {
      await res.body?.cancel().catch(() => {});
      throw new SiteError(def.id, res.status === 404 ? "not_found" : "network", `${what}:HTTP ${res.status}`, {
        httpStatus: res.status,
      });
    }
    return readText(http, res);
  }

  async function run(
    page: number,
    filters: SiteListFilters,
    keyword: string | undefined,
    opts: SiteCallOptions,
  ): Promise<SitePage> {
    const what = keyword ? "搜索" : `列表第 ${page} 页`;
    const spider = new SiteSpider(def, {
      ...(keyword ? { keyword } : {}),
      ...(filters.mtype ? { mtype: filters.mtype } : {}),
      ...(filters.categoryIds?.length ? { cat: filters.categoryIds.join(",") } : {}),
      page: Math.max(1, page) - 1, // 对外 1 起,MP 内部 0 起
    });
    if (!spider.canSearch()) throw new SiteError(def.id, "unsupported", `${what}:站点定义不支持该媒体类型`);
    const html = await fetchPage(spider.getSearchUrl(), what, opts);
    const parsed = spider.parse(html);
    if (parsed.loginPage) throw new SiteError(def.id, "auth_expired", `${what}:返回登录或权限提示页`);
    if (parsed.isError || !parsed.$) throw new SiteError(def.id, "parse_error", `${what}:响应为空`);
    const $ = parsed.$;
    if (parsed.torrents.length === 0) {
      const text = $("body").text();
      const hasList =
        $(normalizeSelector(spider.def.torrents.list.selector)).length > 0 || $("table.torrents").length > 0;
      const empty = (ext.emptyMarkers ?? []).some((m) => text.includes(m));
      if (!hasList && !empty) throw new SiteError(def.id, "parse_error", `${what}:页面结构无法识别(可能改版)`);
      if (ext.loginSuccess && $(ext.loginSuccess).length === 0 && !empty) {
        throw new SiteError(def.id, "auth_expired", `${what}:未找到登录标志`);
      }
    }
    const observedAt = http.now().toISOString();
    let items = parsed.torrents
      .map((t) => spiderTorrentToRelease(t, def, observedAt))
      .filter((r): r is NonNullable<typeof r> => r !== null);
    if (filters.freeOnly) items = items.filter((r) => r.promotion.downloadFactor === 0);
    if (!keyword && filters.categoryIds?.length) {
      // MP 浏览模式不带分类参数;本地按原始分类过滤
      const set = new Set(filters.categoryIds);
      items = items.filter((r) => r.category.id !== null && set.has(r.category.id));
    }
    let maxRaw: number | null = null;
    if (ext.pagination) {
      $(ext.pagination).each((_, el) => {
        const p = Number(/[?&]page=(\d+)/.exec($(el).attr("href") ?? "")?.[1]);
        if (Number.isInteger(p) && (maxRaw === null || p > maxRaw)) maxRaw = p;
      });
    }
    const start = keyword ? 0 : Number(def.browse?.start ?? 0);
    return {
      items,
      page: Math.max(1, page),
      totalPages: maxRaw === null ? null : Math.max(page, (maxRaw as number) - start + 1),
      totalPagesEstimated: true,
      fetchedAt: observedAt,
    };
  }

  return {
    id: def.id,
    kind: ext.kind,
    displayName: ext.displayName ?? def.name,
    capabilities: ext.capabilities,
    definitionVersion: ext.version,

    list(page, filters = {}, opts = {}) {
      return run(page, filters, undefined, opts);
    },

    async search(query, filters = {}, opts = {}) {
      const kw = /^tt\d+$/.test(query.trim()) ? query.trim() : clearSearchText(query);
      if (kw && def.language === "en" && containsChinese(kw)) {
        throw new SiteError(def.id, "unsupported", "该站点不支持中文搜索");
      }
      return run(filters.page ?? 1, filters, kw, opts);
    },

    async detail(siteReleaseId, opts = {}): Promise<SiteReleaseDetail> {
      if (!/^\d+$/.test(siteReleaseId)) throw new SiteError(def.id, "not_found", "资源 ID 非法");
      if (!ext.detail) throw new SiteError(def.id, "unsupported", "站点定义未配置详情页解析");
      const url = new URL(`${ext.detail.path}?id=${siteReleaseId}&hit=1`, base).toString();
      const html = await fetchPage(url, `详情 ${siteReleaseId}`, opts);
      const r = parseDetailPage(html, def, siteReleaseId, http.now().toISOString());
      if (r.kind === "login") throw new SiteError(def.id, "auth_expired", `详情 ${siteReleaseId}:返回登录页`);
      if (r.kind === "not_found") throw new SiteError(def.id, "not_found", `详情 ${siteReleaseId}:资源不存在`);
      if (!r.detail) throw new SiteError(def.id, "parse_error", `详情 ${siteReleaseId}:页面结构无法识别`);
      // 文件清单不在页面上(NexusPHP 点「查看列表」才 AJAX 取)→ 按需 1 次;失败只是没有文件清单
      const flPath = ext.detail.page?.fileListPath;
      if (flPath && r.detail.page && !r.detail.page.files.length) {
        try {
          const flUrl = new URL(flPath.replace("{id}", siteReleaseId), base).toString();
          const frag = await fetchPage(flUrl, `文件清单 ${siteReleaseId}`, opts);
          r.detail.page.files = filesFromFileListHtml(loadHtml(frag));
        } catch (e) {
          if (e instanceof SiteError && e.isAuthError) throw e;
        }
      }
      return r.detail;
    },

    async downloadTarget(siteReleaseId, opts = {}): Promise<DownloadTarget> {
      if (!/^\d+$/.test(siteReleaseId)) throw new SiteError(def.id, "not_found", "资源 ID 非法");
      const what = `下载 ${siteReleaseId}`;
      const url = new URL(`${ext.downloadPath}?id=${siteReleaseId}`, base).toString();
      const res = await siteFetch(http, url, {
        method: "GET",
        headers: { cookie: await cookie(), referer: base },
        redirect: "manual",
        ...(opts.signal ? { signal: opts.signal } : {}),
      });
      const verifiedAt = http.now().toISOString();
      if (res.status >= 300 && res.status < 400) {
        const loc = res.headers.get("location") ?? "";
        await res.body?.cancel().catch(() => {});
        // MP download_torrent:磁力链原样返回
        if (loc.startsWith("magnet:")) return { kind: "magnet", uri: loc, verifiedAt };
        if (/login/i.test(loc)) throw new SiteError(def.id, "auth_expired", `${what}:跳转登录页,Cookie 已失效`);
        throw new SiteError(def.id, "parse_error", `${what}:意外重定向`, { httpStatus: res.status });
      }
      if (!res.ok) {
        await res.body?.cancel().catch(() => {});
        throw new SiteError(def.id, res.status === 404 ? "not_found" : "network", `${what}:HTTP ${res.status}`, {
          httpStatus: res.status,
        });
      }
      const bytes = await readBody(http, res);
      const info = inspectTorrent(bytes);
      if (!info) {
        // 站点在 cookie 失效时常返回 200 + 登录页 HTML
        const $ = loadHtml(new TextDecoder().decode(bytes.subarray(0, 200_000)));
        if (SiteSpider.isLoginOrPermissionPage($)) throw new SiteError(def.id, "auth_expired", `${what}:返回登录页`);
        const text = $("body").text();
        if (ext.detail?.notFoundMarkers.some((m) => text.includes(m))) {
          throw new SiteError(def.id, "not_found", `${what}:资源不存在`);
        }
        throw new SiteError(def.id, "parse_error", `${what}:返回内容不是 .torrent`);
      }
      const disposition = res.headers.get("content-disposition") ?? "";
      const fileName =
        /filename\*=UTF-8''([^;]+)/i.exec(disposition)?.[1] ?? /filename="?([^";]+)"?/i.exec(disposition)?.[1] ?? null;
      return {
        kind: "torrent",
        bytes,
        infoHash: info.infoHash,
        name: info.name,
        fileName: fileName ? decodeURIComponent(fileName) : null,
        verifiedAt,
      };
    },

    async healthCheck(opts = {}): Promise<SiteHealth> {
      const started = Date.now();
      const checkedAt = http.now().toISOString();
      try {
        const html = await fetchPage(new URL("index.php", base).toString(), "健康检查", opts);
        const $ = loadHtml(html);
        if (SiteSpider.isLoginOrPermissionPage($) || (ext.loginSuccess && $(ext.loginSuccess).length === 0)) {
          throw new SiteError(def.id, "auth_expired", "健康检查:未登录");
        }
        return { siteId: def.id, status: "ok", ok: true, checkedAt, latencyMs: Date.now() - started };
      } catch (e) {
        return healthFromError(def.id, e, checkedAt);
      }
    },
  };
}