// ==UserScript==
// @name         423down Article Proxy
// @namespace    https://www.nite07.com/
// @version      1.0.2
// @description  在 423down 文章页自动获取正文 HTML 并替换页面正文区域。
// @author       nite07
// @homepageURL  https://www.nite07.com/
// @match        https://www.423down.com/*.html
// @connect      423.nite07.com
// @connect      *.nite07.com
// @grant        GM_xmlhttpRequest
// @run-at       document-end
// ==/UserScript==

(function () {
  "use strict";

  const API_ORIGIN = "https://423.nite07.com";
  const ARTICLE_PATH_RE = /^\/(\d+)\.html$/;

  const articleID = getArticleID(window.location.pathname);
  if (!articleID) {
    return;
  }

  replaceArticleHTML(articleID);

  function getArticleID(pathname) {
    const match = pathname.match(ARTICLE_PATH_RE);
    return match ? match[1] : "";
  }

  function replaceArticleHTML(articleID) {
    requestArticleHTML(articleID)
      .then((html) => {
        const articleContainer = document.querySelector("div.entry");
        if (!articleContainer) {
          console.warn("[423down-proxy] 未找到正文容器 div.entry，无法替换 HTML");
          return;
        }

        articleContainer.innerHTML = html;
        console.info(`[423down-proxy] 已替换文章 ${articleID} 的正文 HTML`);
      })
      .catch((error) => {
        console.error("[423down-proxy] 获取文章 HTML 失败：", error);
      });
  }

  function requestArticleHTML(articleID) {
    const url = `${API_ORIGIN}/?article_id=${encodeURIComponent(articleID)}`;

    return new Promise((resolve, reject) => {
      GM_xmlhttpRequest({
        method: "GET",
        url,
        responseType: "json",
        timeout: 30_000,
        onload(response) {
          if (response.status < 200 || response.status >= 300) {
            reject(new Error(`HTTP ${response.status}`));
            return;
          }

          const data = parseResponse(response);
          if (!data || data.ok !== true || typeof data.html !== "string") {
            reject(
              new Error(data && data.error ? data.error : "接口响应格式不正确"),
            );
            return;
          }

          resolve(data.html);
        },
        onerror() {
          reject(new Error("网络请求失败"));
        },
        ontimeout() {
          reject(new Error("网络请求超时"));
        },
      });
    });
  }

  function parseResponse(response) {
    if (response.response && typeof response.response === "object") {
      return response.response;
    }

    try {
      return JSON.parse(response.responseText);
    } catch (error) {
      console.error("[423down-proxy] JSON 解析失败：", error);
      return null;
    }
  }
})();