// ==UserScript==
// @name         学习通题目 万能提取器
// @namespace    http://tampermonkey.net/
// @version      3.0.2
// @description  UI全面优化，保留所有核心功能：新增导出docx功能。
// @author       kkkxfr 
// @match        *://*.chaoxing.com/exam-ans/exam/test/reVersionPaperMarkContentNew*
// @match        *://*.chaoxing.com/exam-ans/exam/test/look*
// @match        *://*.chaoxing.com/mooc-ans/work/selectWorkQuestionYiPiYue*
// @match        *://*.mooc1.chaoxing.com/mooc-ans/mooc2/work/view?*
// @match        *://*.chaoxing.com/work/doHomeWorkNew*
// @match        *://*.mooc-ans/work/doHomeWorkNew*
// @match        *://*.mooc1-api.chaoxing.com/mooc-ans/mooc2/work*
// @match        *://*.chaoxing.com/api/selectWorkQuestionYiPiYue*
// @grant        GM_setClipboard
// @grant        GM_addStyle
// @grant        GM_setValue
// @grant        GM_getValue
// @grant        GM_registerMenuCommand
// ==/UserScript==

(function(){
  'use strict';

  const AUTO_EXTRACT_KEY = 'chaoxing_auto_extract_enabled';

  /* ---------- 核心逻辑 Helpers (保持不变) ---------- */
  function normalizeText(s){ if(!s) return ''; return String(s).replace(/\u00A0/g,' ').replace(/\r?\n/g,' ').replace(/\s+/g,' ').trim(); }
  function getCleanText(el){ if(!el) return ''; const c=el.cloneNode(true); c.querySelectorAll('script,style').forEach(x=>x.remove()); let html=c.innerHTML||''; html=html.replace(/<p[^>]*>/gi,'\n').replace(/<br[^>]*>/gi,'\n'); const tmp=document.createElement('div'); tmp.innerHTML=html; return normalizeText(tmp.textContent||tmp.innerText||''); }
  function xmlEscape(s){ if(!s) return ''; return String(s).replace(/&/g,'&amp;').replace(/</g,'&lt;').replace(/>/g,'&gt;').replace(/"/g,'&quot;'); }

  function stripLeadingLabels(s){
    if(!s) return '';
    let t = normalizeText(s);
    while(/^(?:答案解析|正确答案|参考答案|答案)[:：\s]*/i.test(t)){
      t = t.replace(/^(?:答案解析|正确答案|参考答案|答案)[:：\s]*/i, '');
    }
    return t.trim();
  }

  function pullLeadingScore(stem){
    if(!stem) return {score:'', rest: ''};
    const s = stem.trim();
    const m = s.match(/^[,，]?\s*([0-9]+(?:\.[0-9]+)?)\s*分[\)\）]?\s*(.*)$/);
    if(m){
      return { score: m[1] + ' 分', rest: (m[2]||'').trim() };
    }
    return { score: '', rest: s };
  }

  /* ---------- 页面标题提取 ---------- */
  function getPageTitle(){
    const selectors=['#workTitle','.work_title','.courseName','.course-title','.mark_title','.title','h1','h2','.fanyaMarking_left.whiteBg','.detailsHead'];
    for(const sel of selectors){
      try{ const el=document.querySelector(sel); if(el){ const t=normalizeText(el.innerText||el.textContent||''); if(t && t.length>2 && !/error|404|登录|未找到/i.test(t)) return t.split(/\r?\n/)[0]; } }catch(e){}
    }
    const t=normalizeText(document.title||''); if(t && t.length>2) return t; return '试卷';
  }

  /* ---------- 题目解析逻辑 ---------- */
  function findOptionContainers(qNode){
    const sels = ['.mark_letter','.Cy_ulTop','.Zy_ulTop','.options','.option-list','.optionsList'];
    const found = [];
    for(const s of sels){
      const el = qNode.querySelector(s);
      if(el) found.push(el);
    }
    const uls = Array.from(qNode.querySelectorAll('ul,ol'));
    uls.forEach(u=>{
      if((u.className && /ul|options|Cy_ulTop|Zy_ulTop|mark_letter/.test(u.className)) || u.querySelector('li')) {
        if(!found.includes(u)) found.push(u);
      }
    });
    return found;
  }

  function extractCorrectAnswerFromNode(qNode){
    if(!qNode) return null;
    const selectors=['.rightAnswerContent','.right_answer','.answerRight','.Py_answer','.answer-content','.answer'];
    const collected = [];
    selectors.forEach(s=>{
      qNode.querySelectorAll(s).forEach(el=>{
        const t=getCleanText(el);
        if(t && !/未提取|未作答|暂无/i.test(t)) collected.push(t.replace(/\s*[\r\n]+\s*/g,'   '));
      });
    });
    if(collected.length>0) return collected.join('   ');

    const inline = Array.from(qNode.querySelectorAll('p,div,span,li,td'));
    for(const el of inline){
      const t=(el.textContent||'').trim();
      if(!t) continue;
      if(/(?:正确答案|参考答案|答案)[:：]/.test(t) && !/我的答案/i.test(t)){
        const m=t.match(/(?:正确答案|参考答案|答案)[:：]?\s*([\s\S]+)/);
        if(m && m[1]) return m[1].replace(/\s*[\r\n]+\s*/g,'   ').trim();
      }
    }

    const optContainers = findOptionContainers(qNode);
    for(const cont of optContainers){
      const liList = Array.from(cont.querySelectorAll('li'));
      for(const li of liList){
        const inner = li.innerText || '';
        if(/√|正确|selected|checked|icon-ok|dui|check_answer_right/.test(inner)){
          const label = (li.querySelector('.mark_letter_span')?.innerText || li.querySelector('i.fl')?.innerText || '').replace(/[^A-Za-z0-9\u4e00-\u9fa5]/g,'').trim();
          if(label) return label;
          return normalizeText(li.textContent || li.innerText || '');
        }
      }
    }
    const hidden = qNode.querySelector('.element-invisible-hidden, .Py_answer span.element-invisible-hidden');
    if(hidden){
      const t = normalizeText(hidden.innerText||hidden.textContent||'');
      if(t) return t;
    }
    return null;
  }

  function normalizeAnswerString(s, qType){
    if(!s) return '';
    s = normalizeText(s);

    const blanks = s.match(/(?:\(\s*\d+\s*\)|（\s*\d+\s*）)[\s\S]*?(?=(?:\(\s*\d+\s*\)|（\s*\d+\s*）|$))/g);
    if(blanks && blanks.length > 1) return blanks.map(b => normalizeText(b)).join('   ');

    if(qType === '判断题'){
      if(/^(对|正确|true)$/i.test(s)) return '对';
      if(/^(错|错误|false)$/i.test(s)) return '错';
      if(/对|正确|true/i.test(s)) return '对';
      if(/错|错误|false/i.test(s)) return '错';
      return s;
    }

    if(qType === '多选题'){
      const letters = s.match(/[A-D]/gi);
      if(letters){
        return Array.from(new Set(letters.map(x=>x.toUpperCase()))).sort().join('');
      }
      return s;
    }

    let m = s.match(/\b([A-D])\b/i);
    if(m && m[1]) return m[1].toUpperCase();

    const patterns = [
      /^\s*([A-Da-d])[\.\)\、\s]/,
      /[\s\(\[]([A-Da-d])[\.\)\、\s]/,
      /正确答案[:：]?\s*([A-Da-d])/i,
      /答案[:：]?\s*([A-Da-d])/i
    ];
    for(const p of patterns){
      m = s.match(p);
      if(m && m[1]) return m[1].toUpperCase();
    }

    const letters = s.match(/[A-D]/gi);
    if(letters && letters.length>0){
      return letters[0].toUpperCase();
    }
    return s;
  }

  function parseQuestionNode(node){
    try{
      const titleEl = node.querySelector('.mark_name, .Cy_TItle, .Qtitle, .question-title, .marking-title') || node;
      let stemRaw = getCleanText(titleEl) || getCleanText(node);
      let stem = normalizeText(stemRaw).replace(/^\d+[.\、]\s*/,'').trim();

      stem = stem.replace(/^[\(\（]?(?:单选题|多选题|判断题|填空题)[\)\）]?\s*/,'');
      stem = stem.replace(/[\s]*[\(\（](?:单选题|多选题|判断题|填空题)[\)\）][\s]*$/,'');

      const wholeTxt = (node.innerText||node.textContent||'').toLowerCase();
      let type = '单选题';
      if(/多选|multiple|multi/i.test(wholeTxt)) type = '多选题';
      else if(/判断|是非|对错|true|false/i.test(wholeTxt)) type = '判断题';
      else if(/填空|空格|空/i.test(wholeTxt)) type = '填空题';
      else {
        const dt = node.getAttribute && (node.getAttribute('data-type') || node.getAttribute('qtype') || '');
        if(dt && /multi|checkbox|多选/i.test(dt)) type = '多选题';
      }

      const options = [];
      const containers = findOptionContainers(node);
      if(containers.length > 0){
        let chosen = containers.find(c => c.querySelector && c.querySelector('li'));
        if(!chosen) chosen = containers[0];
        if(chosen){
          const lis = Array.from(chosen.querySelectorAll('li'));
          if(lis.length === 0){
            const children = Array.from(chosen.children).filter(ch => normalizeText(ch.innerText||'').length>0);
            children.forEach((ch, idx) => {
              let label = (ch.querySelector('.mark_letter_span')?.innerText || ch.querySelector('i.fl')?.innerText || '').replace(/[^A-Za-z0-9]/g,'').trim();
              let clone = ch.cloneNode(true); if(clone.querySelector('.mark_letter_span')) clone.querySelector('.mark_letter_span').remove(); if(clone.querySelector('i.fl')) clone.querySelector('i.fl').remove();
              let text = normalizeText(clone.textContent || clone.innerText || '');
              const m = text.match(/^[\(\[]?\s*([A-Da-d])[\.\、\)\]\s]+/);
              if(!label && m){ label = m[1].toUpperCase(); text = text.replace(/^[\(\[]?\s*([A-Da-d])[\.\、\)\]\s]+/,'').trim(); }
              if(!label) label = String.fromCharCode(65 + (idx % 26));
              options.push({ key: label.toUpperCase(), text: text.replace(/^[A-D][\.\、\s]*/i,'').trim() });
            });
          } else {
            lis.forEach((li, idx)=>{
              let label = (li.querySelector('.mark_letter_span')?.innerText || li.querySelector('i.fl')?.innerText || '').replace(/[^A-Za-z0-9]/g,'').trim();
              let clone = li.cloneNode(true); if(clone.querySelector('.mark_letter_span')) clone.querySelector('.mark_letter_span').remove(); if(clone.querySelector('i.fl')) clone.querySelector('i.fl').remove();
              let text = normalizeText(clone.textContent || clone.innerText || '');
              const m = text.match(/^[\(\[]?\s*([A-Da-d])[\.\、\)\]\s]+/);
              if(!label && m){ label = m[1].toUpperCase(); text = text.replace(/^[\(\[]?\s*([A-Da-d])[\.\、\)\]\s]+/,'').trim(); }
              if(!label) label = String.fromCharCode(65 + (idx % 26));
              options.push({ key: label.toUpperCase(), text: text.replace(/^[A-D][\.\、\s]*/i,'').trim() });
            });
          }
        }
      } else {
        const immediateLis = Array.from(node.querySelectorAll(':scope > ul > li, :scope > ol > li'));
        immediateLis.forEach((li, idx)=>{
          let label = (li.querySelector('.mark_letter_span')?.innerText || li.querySelector('i.fl')?.innerText || '').replace(/[^A-Za-z0-9]/g,'').trim();
          let clone = li.cloneNode(true); if(clone.querySelector('.mark_letter_span')) clone.querySelector('.mark_letter_span').remove(); if(clone.querySelector('i.fl')) clone.querySelector('i.fl').remove();
          let text = normalizeText(clone.textContent || clone.innerText || '');
          const m = text.match(/^[\(\[]?\s*([A-Da-d])[\.\、\)\]\s]+/);
          if(!label && m){ label = m[1].toUpperCase(); text = text.replace(/^[\(\[]?\s*([A-Da-d])[\.\、\)\]\s]+/,'').trim(); }
          if(!label) label = String.fromCharCode(65 + (idx % 26));
          options.push({ key: label.toUpperCase(), text: text.replace(/^[A-D][\.\、\s]*/i,'').trim() });
        });
      }

      let answerRaw = extractCorrectAnswerFromNode(node) || '';
      answerRaw = stripLeadingLabels(answerRaw);
      let answer = normalizeAnswerString(answerRaw || '', type);

      const analysisEl = node.querySelector('.analysisDiv, .analysis, .py_analyse, .Py_addpy .pingyu, .explain, .analysisTxt');
      let analysis = analysisEl ? getCleanText(analysisEl) : '';
      analysis = stripLeadingLabels(analysis);

      const sectionTitle = findPrevSectionTitle(node) || '';

      return { type, stem, options, answer, analysis, sectionTitle };
    } catch(e){
      console.error('parseQuestionNode error', e);
      return null;
    }
  }

  function findPrevSectionTitle(node){
    const headerSels=['.type_tit','.Cy_TItle1','h2','.markTitle','.typeTitle','.mark_section','.section-title'];
    let cur=node;
    for(let i=0;i<15;i++){
      if(!cur) break;
      let ps=cur.previousElementSibling;
      for(let k=0;k<30 && ps;k++){
        for(const sel of headerSels) {
            if(ps.matches && ps.matches(sel)) {
                const t = normalizeText(ps.innerText||ps.textContent||'');
                if(t && !/^\d+[.、]/.test(t) && !/（\d+.*分）/.test(t) && !/\(\d+.*分\)/.test(t)) {
                    return t;
                }
            }
        }
        ps=ps.previousElementSibling;
      }
      cur=cur.parentElement;
    }
    const headers = Array.from(document.querySelectorAll('h1,h2,h3,.type_tit,.Cy_TItle1,.markTitle'));
    let candidate = null;
    for(const h of headers){
      if(h.compareDocumentPosition(node) & Node.DOCUMENT_POSITION_FOLLOWING) break;
      const t = normalizeText(h.innerText||h.textContent||'');
      if(t && !/^\d+[.、]/.test(t)) candidate = t;
    }
    if(candidate) return candidate;
    return '';
  }

  function buildStructuredPaperFromDOM(){
    const root = document.querySelector('.fanyaMarking') || document.querySelector('.mark_table') || document.body;
    const selectors = ['.questionLi','.TiMu','.question-item','.mark_question','.exam-question','.paper-question','.Ques','.questionBox'];

    const nodeSet = new Set();
    selectors.forEach(sel=>{
      document.querySelectorAll(sel).forEach(n=>{
        if(n && root.contains(n)) nodeSet.add(n);
      });
    });

    if(nodeSet.size === 0){
      const candidates = Array.from(root.querySelectorAll('*'));
      candidates.forEach(n=>{
        try{
          if(!(n instanceof HTMLElement)) return;
          const textLen = (n.innerText||n.textContent||'').trim().length;
          const hasStem = !!n.querySelector('.mark_name, .Cy_TItle, .question-title, .Qtitle');
          const hasOptions = !!n.querySelector('.mark_letter, .Cy_ulTop, .Zy_ulTop, .options, ul, ol');
          if(hasStem || (textLen>12 && hasOptions)) nodeSet.add(n);
        }catch(e){}
      });
    }

    const arr = Array.from(nodeSet);
    arr.sort((a,b)=> {
      if(a===b) return 0;
      const pos = a.compareDocumentPosition(b);
      if(pos & Node.DOCUMENT_POSITION_PRECEDING) return 1;
      if(pos & Node.DOCUMENT_POSITION_FOLLOWING) return -1;
      return 0;
    });

    const parsedQuestions = [];
    const seenFp = new Set();
    for(const node of arr){
      const q = parseQuestionNode(node);
      if(!q) continue;
      const fp = (q.stem+'||'+ q.options.map(o=>o.text).slice(0,8).join('||')).slice(0,2000);
      if(seenFp.has(fp)) continue;
      seenFp.add(fp);
      parsedQuestions.push(q);
    }

    const sectionsMap = new Map();
    for(const q of parsedQuestions){
      const key = q.sectionTitle && q.sectionTitle.trim() ? q.sectionTitle.trim() : '未分组';
      if(!sectionsMap.has(key)) sectionsMap.set(key, []);
      sectionsMap.get(key).push(q);
    }

    const pageTitle = getPageTitle();

    if(sectionsMap.size === 1 && sectionsMap.has('未分组')){
      const allQs = parsedQuestions.slice();
      sectionsMap.clear();
      sectionsMap.set(pageTitle, allQs);
    } else {
      if(sectionsMap.size > 1){
        const headersTop = Array.from(document.querySelectorAll('h1,h2,.detailsHead,.fanyaMarking_left')).filter(h => {
          try { return h.getBoundingClientRect && h.getBoundingClientRect().top < 240; } catch(e) { return false; }
        });
        if(headersTop.length === 1){
          const merged = [];
          for(const arrQ of sectionsMap.values()) merged.push(...arrQ);
          sectionsMap.clear();
          sectionsMap.set(normalizeText(headersTop[0].innerText||headersTop[0].textContent||pageTitle), merged);
        }
      }
    }

    const sections = [];
    for(const [title, qlist] of sectionsMap.entries()){
      let orderIndex = Infinity;
      const headers = Array.from(document.querySelectorAll('h1,h2,h3,.type_tit,.Cy_TItle1,.markTitle'));
      headers.forEach((h, idx) => { if(normalizeText(h.innerText||h.textContent||'') === normalizeText(title) && orderIndex===Infinity) orderIndex = idx; });
      sections.push({ title, qlist, orderIndex });
    }
    sections.sort((a,b) => {
      if(a.orderIndex === Infinity && b.orderIndex===Infinity) return 0;
      if(a.orderIndex === Infinity) return 1;
      if(b.orderIndex === Infinity) return -1;
      return a.orderIndex - b.orderIndex;
    });

    let counter = 1;
    const paper = { title: pageTitle, sections: [] };
    for(const s of sections){
      const sec = { title: s.title, questions: [] };
      for(const q of s.qlist){
        q.no = counter++;
        sec.questions.push(q);
      }
      paper.sections.push(sec);
    }

    if(paper.sections.length === 0){
      const fallbackNodes = Array.from(document.querySelectorAll('.TiMu,.questionLi'));
      if(fallbackNodes.length>0){
        const sec = { title: pageTitle || '题目', questions: [] };
        for(const node of fallbackNodes){
          const q = parseQuestionNode(node);
          if(q){ q.no = counter++; sec.questions.push(q); }
        }
        if(sec.questions.length) paper.sections.push(sec);
      }
    }

    return paper;
  }

  /* ---------- Word 生成 (无需变动逻辑) ---------- */
  function buildContentTypes(){ return '<?xml version="1.0" encoding="UTF-8"?><Types xmlns="http://schemas.openxmlformats.org/package/2006/content-types"><Default Extension="rels" ContentType="application/vnd.openxmlformats-package.relationships+xml"/><Default Extension="xml" ContentType="application/xml"/><Override PartName="/word/document.xml" ContentType="application/vnd.openxmlformats-officedocument.wordprocessingml.document.main+xml"/><Override PartName="/word/styles.xml" ContentType="application/vnd.openxmlformats-officedocument.wordprocessingml.styles+xml"/></Types>'; }
  function buildRels(){ return '<?xml version="1.0" encoding="UTF-8"?><Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships"><Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument" Target="word/document.xml"/></Relationships>'; }
  function buildStyles(){ return '<?xml version="1.0" encoding="UTF-8"?><w:styles xmlns:w="http://schemas.openxmlformats.org/wordprocessingml/2006/main"><w:style w:type="paragraph" w:styleId="Normal"><w:name w:val="Normal"/></w:style></w:styles>'; }

  function buildDocumentXmlFromPaper(paper){
    const questionsFlat = []; for(const s of paper.sections) for(const q of s.questions) questionsFlat.push(q);
    const totalCount = questionsFlat.length;

    let xml='<?xml version="1.0" encoding="UTF-8" standalone="yes"?><w:document xmlns:w="http://schemas.openxmlformats.org/wordprocessingml/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships"><w:body>';

    xml += `<w:p><w:pPr><w:jc w:val="center"/></w:pPr><w:r><w:rPr><w:b/><w:sz w:val="32"/></w:rPr><w:t>${xmlEscape(paper.title)}</w:t></w:r></w:p>`;
    xml += `<w:p><w:pPr><w:jc w:val="center"/></w:pPr><w:r><w:rPr><w:b/><w:sz w:val="28"/></w:rPr><w:t>${xmlEscape('（共 ' + totalCount + ' 题）')}</w:t></w:r></w:p>`;
    xml += `<w:p/>`;

    for(const sec of paper.sections){
      if(normalizeText(sec.title) !== normalizeText(paper.title) && !/未分组|题目|^$|^\d+[.、]/.test(sec.title)){
           xml += `<w:p><w:pPr><w:jc w:val="left"/></w:pPr><w:r><w:rPr><w:b/><w:sz w:val="24"/></w:rPr><w:t>${xmlEscape(sec.title)}</w:t></w:r></w:p>`;
      }

      for(const q of sec.questions){
        const scoreInfo = pullLeadingScore(q.stem);
        let stemBody = scoreInfo.score ? scoreInfo.rest : q.stem;
        stemBody = (stemBody||'').trim();
        const heading = scoreInfo.score ? `${q.no}. (${q.type} , ${scoreInfo.score}) ${stemBody}` : `${q.no}. (${q.type}) ${stemBody || q.stem}`;
        xml += `<w:p><w:r><w:rPr><w:b/></w:rPr><w:t>${xmlEscape(heading)}</w:t></w:r></w:p>`;

        if(q.options && q.options.length){
          for(let i=0;i<q.options.length;i++){
            const op = q.options[i];
            const label = (op.key && op.key.length>0) ? op.key : String.fromCharCode(65 + (i % 26));
            const text = op.text || '';
            xml += `<w:p><w:pPr><w:ind w:left="420"/></w:pPr><w:r><w:t>${xmlEscape(label + '. ' + text)}</w:t></w:r></w:p>`;
          }
        }
        xml += `<w:p/>`;
      }
    }

    xml += `<w:p/><w:p><w:r><w:rPr><w:b/><w:sz w:val="24"/></w:rPr><w:t>参考答案</w:t></w:r></w:p>`;
    const cols=8; const rows=Math.ceil(Math.max(questionsFlat.length,1)/cols);
    xml += `<w:tbl><w:tblPr><w:tblW w:w="0" w:type="auto"/><w:tblBorders><w:top w:val="single" w:sz="4"/><w:left w:val="single" w:sz="4"/><w:bottom w:val="single" w:sz="4"/><w:right w:val="single" w:sz="4"/><w:insideH w:val="single" w:sz="4"/><w:insideV w:val="single" w:sz="4"/></w:tblBorders></w:tblPr>`;
    let idx=0;
    for(let r=0;r<rows;r++){
      xml += `<w:tr><w:trPr><w:trHeight w:val="400" w:hRule="atLeast"/></w:trPr>`;
      for(let c=0;c<cols;c++){
        const txt = idx < questionsFlat.length ? (questionsFlat[idx].no + '.' + stripLeadingLabels(questionsFlat[idx].answer || '')) : '';
        xml += `<w:tc><w:tcPr><w:tcW w:w="1200" w:type="dxa"/><w:vAlign w:val="center"/></w:tcPr><w:p><w:pPr><w:jc w:val="center"/></w:pPr><w:r><w:t>${xmlEscape(txt)}</w:t></w:r></w:p></w:tc>`;
        idx++;
      }
      xml += `</w:tr>`;
    }
    xml += `</w:tbl>`;

    const analyses = questionsFlat.filter(q=> q.analysis && q.analysis.trim());
    if(analyses.length){
      xml += `<w:p/><w:p><w:r><w:rPr><w:b/><w:sz w:val="24"/></w:rPr><w:t>答案解析</w:t></w:r></w:p>`;
      for(const q of analyses){
        const scoreInfo = pullLeadingScore(q.stem);
        const headText = scoreInfo.score ? `${q.no}. (${scoreInfo.score}) ${scoreInfo.rest}` : `${q.no}. ${q.stem}`;
        xml += `<w:p><w:pPr><w:jc w:val="left"/></w:pPr><w:r><w:rPr><w:b/></w:rPr><w:t>${xmlEscape(headText)}</w:t></w:r></w:p>`;
        xml += `<w:p><w:pPr><w:ind w:left="420"/></w:pPr><w:r><w:t>${xmlEscape(stripLeadingLabels(q.analysis))}</w:t></w:r></w:p>`;
        xml += `<w:p/>`;
      }
    }

    xml += `<w:sectPr><w:pgMar w:top="1440" w:right="1440" w:bottom="1440" w:left="1440"/></w:sectPr>`;
    xml += `</w:body></w:document>`;
    return xml;
  }

  /* ---------- ZIP 导出 ---------- */
  function strToUint8(s){ return new TextEncoder().encode(s); }
  function uint32ToLE(n){ return [n & 0xff, (n>>>8)&0xff, (n>>>16)&0xff, (n>>>24)&0xff]; }
  function uint16ToLE(n){ return [n & 0xff, (n>>>8)&0xff]; }
  function crc32(buf){ const table = crc32.table || (crc32.table=(function(){ const t=new Uint32Array(256); for(let n=0;n<256;n++){ let c=n; for(let k=0;k<8;k++){ c=(c&1)?(0xEDB88320^(c>>>1)):(c>>>1); } t[n]=c>>>0; } return t; })()); let crc=0^(-1); for(let i=0;i<buf.length;i++) crc=(crc>>>8) ^ table[(crc ^ buf[i]) & 0xff]; return (crc ^ (-1))>>>0; }
  function buildZip(files){
    const localEntries=[]; let offset=0;
    for(const f of files){
      const nameBuf=strToUint8(f.name); const data=f.data; const crc=crc32(data); const compSize=data.length; const uncompSize=data.length;
      const localHeader=[...uint32ToLE(0x04034b50), ...uint16ToLE(20), ...uint16ToLE(0), ...uint16ToLE(0), ...uint16ToLE(0), ...uint16ToLE(0), ...uint32ToLE(crc), ...uint32ToLE(compSize), ...uint32ToLE(uncompSize), ...uint16ToLE(nameBuf.length), ...uint16ToLE(0)];
      const headerBuf=new Uint8Array(localHeader.length + nameBuf.length + data.length);
      headerBuf.set(new Uint8Array(localHeader),0); headerBuf.set(nameBuf, localHeader.length); headerBuf.set(data, localHeader.length + nameBuf.length);
      localEntries.push({ name: f.name, headerBuf, crc, compSize, uncompSize, offset }); offset += headerBuf.length;
    }
    const cdParts=[]; let cdSize=0;
    for(const e of localEntries){
      const nameBuf=strToUint8(e.name);
      const cdr=[...uint32ToLE(0x02014b50), ...uint16ToLE(0x0314), ...uint16ToLE(20), ...uint16ToLE(0), ...uint16ToLE(0), ...uint16ToLE(0), ...uint16ToLE(0), ...uint32ToLE(e.crc), ...uint32ToLE(e.compSize), ...uint32ToLE(e.uncompSize), ...uint16ToLE(nameBuf.length), ...uint16ToLE(0), ...uint16ToLE(0), ...uint16ToLE(0), ...uint16ToLE(0), ...uint32ToLE(0), ...uint32ToLE(e.offset)];
      const cdbuf=new Uint8Array(cdr.length + nameBuf.length); cdbuf.set(new Uint8Array(cdr),0); cdbuf.set(nameBuf, cdr.length);
      cdParts.push(cdbuf); cdSize += cdbuf.length;
    }
    const total = offset + cdSize + 22; const out=new Uint8Array(total);
    let pos=0;
    for(const e of localEntries){ out.set(e.headerBuf, pos); pos += e.headerBuf.length; }
    for(const c of cdParts){ out.set(c, pos); pos += c.length; }
    const eocd=[...uint32ToLE(0x06054b50), ...uint16ToLE(0), ...uint16ToLE(0), ...uint16ToLE(localEntries.length), ...uint16ToLE(localEntries.length), ...uint32ToLE(cdSize), ...uint32ToLE(offset), ...uint16ToLE(0)];
    out.set(new Uint8Array(eocd), pos);
    return out;
  }

  function exportPaperToDocx(paper){
    let n=1; for(const s of paper.sections) for(const q of s.questions) if(!q.no) q.no = n++;
    const docXml = buildDocumentXmlFromPaper(paper);
    const files=[ { name:'[Content_Types].xml', data: strToUint8(buildContentTypes()) }, { name:'_rels/.rels', data: strToUint8(buildRels()) }, { name:'word/document.xml', data: strToUint8(docXml) }, { name:'word/styles.xml', data: strToUint8(buildStyles()) } ];
    const zipBuf = buildZip(files);
    const blob = new Blob([zipBuf], { type:'application/vnd.openxmlformats-officedocument.wordprocessingml.document' });
    const a=document.createElement('a'); const safe = (paper.title || getPageTitle()).replace(/[\\\/:*?"<>|]+/g,'_');
    a.href = URL.createObjectURL(blob); a.download = safe + '.docx'; document.body.appendChild(a); a.click();
    setTimeout(()=>{ document.body.removeChild(a); URL.revokeObjectURL(a.href); }, 3000);
  }

  /* ---------- UI & Main Flow (Optimized UI) ---------- */
  function structuredPaperToText(paper){
    let out = `# ${paper.title}\n\n`;
    for(const sec of paper.sections){
      if(sec.title && !/未分组|题目|^$|^\d+[.、]/.test(sec.title) && sec.title !== paper.title){
        out += `## ${sec.title}（共 ${sec.questions.length} 题）\n\n`;
      }
      for(const q of sec.questions){
        const scoreInfo = pullLeadingScore(q.stem);
        if(scoreInfo.score){
          const rest = scoreInfo.rest || '';
          out += `${q.no}. (${q.type} , ${scoreInfo.score}) ${rest}\n`;
        } else {
          out += `${q.no}. (${q.type}) ${q.stem}\n`;
        }
        if(q.options && q.options.length) for(let i=0;i<q.options.length;i++){
          const op = q.options[i];
          const label = (op.key && op.key.length>0) ? op.key : String.fromCharCode(65 + (i % 26));
          out += `  ${label}. ${op.text}\n`;
        }
        if(q.answer) out += `正确答案：${stripLeadingLabels(q.answer)}\n`;
        if(q.analysis) out += `答案解析：${stripLeadingLabels(q.analysis)}\n`;
        out += `\n`;
      }
    }
    return out;
  }

  function extractAndShow(isManual=false){
    const paper = buildStructuredPaperFromDOM();
    const total = paper.sections.reduce((s,sec)=>s + (sec.questions||[]).length, 0);
    if(total === 0){ if(isManual) showNotification('未找到题目 — 请确认页面已加载或切换到答题/查看页', true); return; }
    const text = structuredPaperToText(paper);
    GM_setClipboard(text);
    showUI(text, paper);
    showNotification(`已提取 ${total} 道题（复制到剪贴板）`);
  }

  let notificationElement = null;
  function showNotification(msg, isError=false){
    if(!notificationElement){ notificationElement = document.createElement('div'); notificationElement.id='cx-notification-gm'; document.body.appendChild(notificationElement); }
    notificationElement.innerHTML = `<span>${isError?'⚠️':'✅'}</span> ${msg}`;
    notificationElement.className = isError ? 'error' : 'success';
    notificationElement.style.display = 'flex'; notificationElement.style.animation = 'none'; notificationElement.offsetHeight;
    notificationElement.style.animation = 'cx-slide-in 0.3s forwards';
    setTimeout(()=>{ notificationElement.style.animation = 'cx-slide-out 0.3s forwards'; setTimeout(()=>{ notificationElement.style.display='none'; },300); }, 2500);
  }

  /* ---------- New UI Construction ---------- */
  let uiContainer = null;
  let uiOverlay = null;

  function showUI(text, paper){
    if(!uiContainer){
      // Overlay
      uiOverlay = document.createElement('div');
      uiOverlay.id = 'cx-ui-overlay';
      document.body.appendChild(uiOverlay);
      uiOverlay.onclick = closeUI;

      // Main Modal
      uiContainer = document.createElement('div');
      uiContainer.id = 'cx-extractor-ui';
      uiContainer.innerHTML = `
        <div class="cx-header">
          <div class="cx-title"><span class="cx-icon">📝</span> 提取结果预览</div>
          <div class="cx-close-icon" id="cx-close-icon" title="关闭">×</div>
        </div>
        <div class="cx-body">
          <textarea id="cx-extractor-output" readonly placeholder="提取结果将显示在这里..."></textarea>
        </div>
        <div class="cx-footer">
          <button id="cx-copy" class="cx-btn cx-btn-primary">
            <span>📄</span> 复制文本
          </button>
          <button id="cx-export" class="cx-btn cx-btn-success">
            <span>📄</span> 导出 Word
          </button>
          <button id="cx-close" class="cx-btn cx-btn-secondary">
            关闭
          </button>
        </div>
      `;
      document.body.appendChild(uiContainer);

      // Event Bindings
      document.getElementById('cx-close-icon').onclick = closeUI;
      document.getElementById('cx-close').onclick = closeUI;
      document.getElementById('cx-copy').onclick = () => {
        const ta = document.getElementById('cx-extractor-output');
        ta.select();
        GM_setClipboard(ta.value);
        showNotification('已复制到剪贴板');
      };
      document.getElementById('cx-export').onclick = () => exportPaperToDocx(paper);
    }

    const ta = document.getElementById('cx-extractor-output');
    if(ta) ta.value = text;
    
    // Show Animation
    uiOverlay.style.display = 'block';
    // small delay to trigger transition
    requestAnimationFrame(() => {
        uiOverlay.style.opacity = '1';
        uiContainer.classList.add('active');
    });
  }

  function closeUI(){
    if(!uiContainer) return;
    uiOverlay.style.opacity = '0';
    uiContainer.classList.remove('active');
    setTimeout(() => {
        uiOverlay.style.display = 'none';
    }, 300);
  }

  function createFloatingButton(){
    if(document.getElementById('cx-float-btn')) return;
    const btn = document.createElement('button');
    btn.id = 'cx-float-btn';
    btn.innerHTML = '📝';
    btn.title = '提取题目';
    btn.onclick = () => extractAndShow(true);
    document.body.appendChild(btn);
  }

  function toggleAuto(){ const v = !GM_getValue(AUTO_EXTRACT_KEY,false); GM_setValue(AUTO_EXTRACT_KEY,v); alert(`自动提取已${v?'开启':'关闭'}，刷新页面生效。`); updateMenu(); }
  function updateMenu(){ const isAuto = GM_getValue(AUTO_EXTRACT_KEY,false); try{ GM_registerMenuCommand(`${isAuto?'✅':'❌'} 自动提取开关`, toggleAuto); GM_registerMenuCommand('🖐 手动提取题目', ()=> extractAndShow(true)); }catch(e){ console.warn('GM_registerMenuCommand 可能不可用', e); } }

  /* ---------- Modern CSS ---------- */
  GM_addStyle(`
    /* Overlay */
    #cx-ui-overlay {
        position: fixed; inset: 0; background: rgba(0,0,0,0.4); z-index: 99997;
        backdrop-filter: blur(2px); display: none; opacity: 0; transition: opacity 0.3s;
    }
    /* Main Modal Center */
    #cx-extractor-ui {
        position: fixed; top: 50%; left: 50%; transform: translate(-50%, -50%) scale(0.95);
        width: 600px; max-width: 90vw; max-height: 85vh;
        background: #fff; border-radius: 16px;
        box-shadow: 0 20px 60px rgba(0,0,0,0.2);
        z-index: 99998; display: flex; flex-direction: column;
        opacity: 0; pointer-events: none; transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
        font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    }
    #cx-extractor-ui.active {
        opacity: 1; pointer-events: auto; transform: translate(-50%, -50%) scale(1);
    }
    /* Header */
    .cx-header {
        padding: 16px 24px; border-bottom: 1px solid #f0f0f0;
        display: flex; justify-content: space-between; align-items: center;
        background: #fff; border-radius: 16px 16px 0 0;
    }
    .cx-title { font-size: 18px; font-weight: 600; color: #333; display: flex; align-items: center; gap: 8px; }
    .cx-close-icon { font-size: 24px; cursor: pointer; line-height: 1; color: #999; transition: color 0.2s; }
    .cx-close-icon:hover { color: #333; }
    /* Body */
    .cx-body { flex: 1; padding: 0; overflow: hidden; display: flex; flex-direction: column; background: #fafafa; }
    #cx-extractor-output {
        width: 100%; height: 400px; padding: 20px; border: none;
        font-family: 'Consolas', 'Monaco', monospace; font-size: 13px;
        color: #444; background: #fafafa; line-height: 1.6; resize: none; outline: none;
        box-sizing: border-box;
    }
    /* Footer */
    .cx-footer {
        padding: 16px 24px; border-top: 1px solid #f0f0f0;
        display: flex; gap: 12px; background: #fff; border-radius: 0 0 16px 16px;
    }
    .cx-btn {
        flex: 1; padding: 12px 0; border: none; border-radius: 8px;
        font-size: 14px; font-weight: 600; cursor: pointer;
        transition: transform 0.1s, filter 0.2s; display: flex; align-items: center; justify-content: center; gap: 6px;
    }
    .cx-btn:active { transform: scale(0.98); }
    .cx-btn-primary { background: #1890ff; color: #fff; box-shadow: 0 4px 12px rgba(24,144,255,0.25); }
    .cx-btn-success { background: #52c41a; color: #fff; box-shadow: 0 4px 12px rgba(82,196,26,0.25); }
    .cx-btn-secondary { background: #f5f5f5; color: #666; border: 1px solid #e8e8e8; }
    .cx-btn:hover { filter: brightness(1.05); }

    /* Floating Button */
    #cx-float-btn {
        position: fixed; top: 180px; right: 20px; z-index: 99999;
        width: 56px; height: 56px; border-radius: 50%;
        background: linear-gradient(135deg, #1890ff, #096dd9);
        color: #fff; border: none; font-size: 24px;
        box-shadow: 0 6px 20px rgba(24,144,255,0.4);
        cursor: pointer; transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
        display: flex; align-items: center; justify-content: center;
    }
    #cx-float-btn:hover { transform: scale(1.1) rotate(10deg); }
    
    /* Notification */
    #cx-notification-gm {
        position: fixed; top: 30px; left: 50%; transform: translateX(-50%);
        padding: 12px 24px; border-radius: 30px;
        display: flex; align-items: center; gap: 8px;
        box-shadow: 0 10px 30px rgba(0,0,0,0.15);
        z-index: 100000; font-family: -apple-system, sans-serif;
        font-size: 14px; font-weight: 600; pointer-events: none;
        background: #fff; color: #333; border: 1px solid #eee;
    }
    #cx-notification-gm.success span { color: #52c41a; }
    #cx-notification-gm.error span { color: #ff4d4f; }
    
    @keyframes cx-slide-in { from { transform: translate(-50%, -20px); opacity: 0; } to { transform: translate(-50%, 0); opacity: 1; } }
    @keyframes cx-slide-out { from { transform: translate(-50%, 0); opacity: 1; } to { transform: translate(-50%, -20px); opacity: 0; } }
  `);

  updateMenu();
  createFloatingButton();
  window.addEventListener('load', ()=> { if(GM_getValue(AUTO_EXTRACT_KEY,false)) setTimeout(()=> extractAndShow(false), 1500); });

})();