/* 真实浏览器验证：只启动本机测试服务，不请求原网站。 */
const assert = require('node:assert/strict');
const fs = require('node:fs');
const path = require('node:path');
const os = require('node:os');
const http = require('node:http');
const { chromium } = require('playwright');

const root = path.resolve(__dirname, '..');
const coreSource = fs.readFileSync(path.join(root, 'question-bank-core.js'), 'utf8');
const scriptSource = fs.readFileSync(path.join(root, '谊安学题库导出.user.js'), 'utf8');
const qaDir = process.env.YIAN_QA_DIR || path.join(os.tmpdir(), 'yianxue-export-qa');
fs.mkdirSync(qaDir, { recursive: true });
const samplePath = path.join(root, '网页样本', '考试答案', '谊安学.html');

function option(label, text, selected = false) {
  return `<div class="pc_examtest_content_list_child1"><div class="pc_examtest_content_list_des${selected ? ' examtest_content_list_des_checked' : ''}" onclick="window.answerClicks++"><span class="examtest_content_list_des_optionsort">${label}</span>${text}</div></div>`;
}
function fixture(title = '模拟练习', { missingAnswer = false, cardCount = 3 } = {}) {
  const content = [
    { type: '单选', stem: '包含引号的项目 "甲,乙"？', options: [option('A', '错误选择', true), option('B', '正确选项')], answer: '<span class="answer">B</span>', explanation: '请依据参考答案。' },
    { type: '多选', stem: '选择符合条件的项目。', options: ['A', 'B', 'C', 'D', 'E'].map(x => option(x, '项目' + x)), answer: '<span class="answer">A</span><span class="answer">E</span>', explanation: '' },
    { type: '判断', stem: '隐藏答案应能读取。', options: [option('A', '对'), option('B', '错')], answer: missingAnswer ? '' : '<span class="answer">B</span>', explanation: '' }
  ].map((q, i) => `<div class="pc_exam_list" app-exam-question><a id="examtest${i}"></a><div class="pc_examtest_content"><div class="pc_examtest_content_question"><p><span>[${q.type}]</span> ${i + 1}. ${q.stem}<span class="pc_examtest_content_question_showanswer" onclick="window.answerClicks++">查看答案</span></p></div><div class="pc_examtest_content_list">${q.options.join('')}</div><div class="hidden"><div class="pc_examtest_content_answer_top"><div class="examtest_content_answer_left">参考答案：${q.answer}</div><div>答错了</div></div><div class="pc_examtest_content_resolve">题目解析：<span>${q.explanation}</span></div></div></div></div>`).join('');
  return `<!doctype html><title>模拟谊安学练习</title><style>.hidden{display:none}body{font:16px system-ui;margin:30px}.pc_examtest_content{padding:15px;border-bottom:1px solid #ddd}.pc_examtest_title{font-size:24px}</style><app-examtest><div class="pc_examtest_title">${title}</div>${content}<div class="pc_examtest_card">${Array.from({ length: cardCount }, (_, i) => `<div class="examtestcard_count_defult">${i + 1}</div>`).join('')}</div></app-examtest>`;
}

function parseCSV(text) {
  text = text.replace(/^\uFEFF/, '');
  const rows = []; let row = []; let cell = ''; let quoted = false;
  for (let i = 0; i < text.length; i++) {
    const ch = text[i];
    if (ch === '"') {
      if (quoted && text[i + 1] === '"') { cell += '"'; i++; }
      else quoted = !quoted;
    } else if (!quoted && ch === ',') { row.push(cell); cell = ''; }
    else if (!quoted && (ch === '\r' || ch === '\n')) {
      if (ch === '\r' && text[i + 1] === '\n') i++;
      row.push(cell); rows.push(row); row = []; cell = '';
    } else cell += ch;
  }
  if (cell || row.length) { row.push(cell); rows.push(row); }
  assert.equal(quoted, false, 'CSV 引号需成对');
  return rows;
}

(async function main() {
  const server = http.createServer((req, res) => {
    const requestURL = new URL(req.url, 'http://localhost');
    if (requestURL.pathname.endsWith('/question-bank-core.js')) {
      res.writeHead(200, { 'Content-Type': 'text/javascript;charset=utf-8' }); res.end(coreSource);
    } else if (requestURL.pathname.startsWith('/tool/')) {
      res.writeHead(200, { 'Content-Type': 'text/html;charset=utf-8' }); res.end(fs.readFileSync(path.join(root, '离线导出题库.html')));
    } else {
      res.writeHead(200, { 'Content-Type': 'text/html;charset=utf-8' }); res.end(fixture(requestURL.searchParams.get('title') || '模拟练习'));
    }
  });
  await new Promise(resolve => server.listen(0, '127.0.0.1', resolve));
  const origin = `http://127.0.0.1:${server.address().port}`;
  let browser;
  try {
    browser = await chromium.launch({ channel: process.env.PLAYWRIGHT_CHANNEL || 'chrome', headless: true });
    const context = await browser.newContext({ acceptDownloads: true, viewport: { width: 1366, height: 900 } });
    const page = await context.newPage();
    const errors = []; page.on('pageerror', error => errors.push(error.message));
    page.on('console', message => { if (message.type() === 'error' || message.type() === 'warning') errors.push(message.text()); });
    const downloads = []; page.on('download', download => downloads.push(download));
    const practiceURL = title => origin + '/clientcn/exam/' + encodeURIComponent(title) + '/questions?title=' + encodeURIComponent(title) + '&flag=exercise';
    await page.goto(practiceURL('模拟练习'));
    await page.evaluate(() => { window.answerClicks = 0; });
    const firstDownload = page.waitForEvent('download');
    await page.addScriptTag({ content: scriptSource });
    const downloaded = await firstDownload;
    await downloaded.saveAs(path.join(qaDir, 'synthetic.csv'));
    const bank = await page.evaluate(() => QuestionBankCore.extract(document));
    assert.equal(bank.total, 3); assert.equal(bank.answered, 3); assert.equal(bank.complete, true);
    assert.equal(bank.questions[0].answer, 'B'); assert.equal(bank.questions[0].options[0].text, '错误选择');
    assert.equal(bank.questions[1].answer, 'AE'); assert.equal(bank.questions[1].options.length, 5);
    assert.equal(bank.questions[2].answerText, 'B. 错'); assert.equal(bank.questions[0].explanation, '请依据参考答案。');
    assert(bank.questions.every(q => !q.question.includes('查看答案')));
    assert.equal(await page.evaluate(() => window.answerClicks), 0);
    const csv = fs.readFileSync(path.join(qaDir, 'synthetic.csv'), 'utf8');
    assert.equal(csv.charCodeAt(0), 0xFEFF);
    const rows = parseCSV(csv); assert.equal(rows.length, 4);
    assert(rows.every(row => row.length === rows[0].length));
    assert.equal(rows[1][rows[0].indexOf('题目')], '包含引号的项目 "甲,乙"？');
    assert(rows[0].includes('选项E'));
    const formulaCSV = await page.evaluate(() => {
      const b = QuestionBankCore.extract(document); b.questions[0].question = '=HYPERLINK("http://invalid")'; return QuestionBankCore.toCSV(b);
    });
    assert(parseCSV(formulaCSV)[1][2].startsWith("'="));
    await page.waitForTimeout(2400); assert.equal(downloads.length, 1, '同一题库不应重复自动下载');
    await page.screenshot({ path: path.join(qaDir, 'practice-desktop.png') });
    console.log('PASS 隐藏答案、错误已选项隔离、多选、判断、完整CSV与单次自动下载');

    // 新 URL 与新 DOM 在下一次扫描前一同更新，仍应成功自动导出。
    const nextDownload = page.waitForEvent('download');
    await page.evaluate(({ url, html }) => {
      history.pushState({}, '', url);
      const doc = new DOMParser().parseFromString(html, 'text/html');
      document.querySelector('app-examtest').replaceWith(doc.querySelector('app-examtest'));
    }, { url: practiceURL('第二份练习'), html: fixture('第二份练习') });
    assert.equal((await nextDownload).suggestedFilename(), '第二份练习_题库_3题.csv');
    console.log('PASS SPA 页面与地址同步切换自动导出');

    // URL 先改变、旧内容仍在时不得导出旧题；题目延后到达再导出。
    const beforeDelayed = downloads.length;
    await page.evaluate(url => history.pushState({}, '', url), practiceURL('延迟练习'));
    await page.waitForTimeout(2600); assert.equal(downloads.length, beforeDelayed);
    const delayedDownload = page.waitForEvent('download');
    await page.evaluate(html => {
      const doc = new DOMParser().parseFromString(html, 'text/html');
      document.querySelector('app-examtest').innerHTML = doc.querySelector('app-examtest').innerHTML;
    }, fixture('延迟练习'));
    assert.equal((await delayedDownload).suggestedFilename(), '延迟练习_题库_3题.csv');
    console.log('PASS SPA 旧页面残留与延迟加载等待');

    const beforeMissing = downloads.length;
    await page.evaluate(({ url, html }) => {
      history.pushState({}, '', url);
      document.querySelector('app-examtest').innerHTML = new DOMParser().parseFromString(html, 'text/html').querySelector('app-examtest').innerHTML;
    }, { url: practiceURL('缺答案练习'), html: fixture('缺答案练习', { missingAnswer: true }) });
    await page.waitForTimeout(2600); assert.equal(downloads.length, beforeMissing);
    assert((await page.locator('#yian-question-bank-exporter').innerText()).includes('缺少 1 个答案'));
    const manual = page.waitForEvent('download'); await page.getByRole('button', { name: '导出 CSV', exact: true }).click();
    assert((await manual).suggestedFilename().includes('_不完整'));
    const missing = await page.evaluate(() => QuestionBankCore.extract(document));
    assert.equal(missing.complete, false); assert.deepEqual(missing.missingAnswers, [3]);
    console.log('PASS 缺答案不自动下载，手动导出标记不完整');

    await page.evaluate(({ url, html }) => {
      history.pushState({}, '', url);
      document.querySelector('app-examtest').innerHTML = new DOMParser().parseFromString(html, 'text/html').querySelector('app-examtest').innerHTML;
    }, { url: practiceURL('缺题练习'), html: fixture('缺题练习', { cardCount: 4 }) });
    const beforeCount = downloads.length;
    await page.waitForTimeout(2600); assert.equal(downloads.length, beforeCount);
    assert((await page.locator('#yian-question-bank-exporter').innerText()).includes('3 / 4'));
    await page.evaluate(() => history.pushState({}, '', location.href.replace('flag=exercise', 'flag=exam')));
    await page.waitForTimeout(1100); assert.equal(await page.locator('#yian-question-bank-exporter').count(), 0);
    assert.equal(await page.evaluate(() => window.answerClicks), 0);
    console.log('PASS 缺题等待、考试页面不触发、不改变答题状态');

    const sampleHTML = fs.existsSync(samplePath) ? fs.readFileSync(samplePath, 'utf8') : fixture();
    const tool = await context.newPage();
    tool.on('pageerror', error => errors.push(error.message));
    tool.on('console', message => { if (message.type() === 'error' || message.type() === 'warning') errors.push(message.text()); });
    const toolURL = require('node:url').pathToFileURL(path.join(root, '离线导出题库.html')).href;
    await tool.goto(toolURL);
    assert.equal(tool.url(), toolURL);
    assert.equal(await tool.title(), '离线导出题库');
    assert(await tool.getByRole('heading', { name: '从已保存的练习网页导出题库' }).isVisible());
    const sourceRequests = [];
    tool.on('request', request => { if (!request.url().startsWith(origin)) sourceRequests.push(request.url()); });
    await tool.locator('#file').setInputFiles({ name: '谊安学.html', mimeType: 'text/html', buffer: Buffer.from(sampleHTML) });
    await tool.locator('#csv').waitFor({ state: 'visible' });
    await tool.waitForFunction(() => !document.getElementById('csv').disabled);
    assert.equal(sourceRequests.length, 0, '解析网页时不应请求原网站资源');
    const realBank = await tool.evaluate(html => QuestionBankCore.extract(QuestionBankCore.parseHTML(html)), sampleHTML);
    if (fs.existsSync(samplePath)) {
      assert.equal(realBank.total, 120); assert.equal(realBank.answered, 120); assert.equal(realBank.expectedTotal, 120);
      assert.equal(realBank.complete, true);
      assert.deepEqual(realBank.questions.reduce((o, q) => (o[q.type] = (o[q.type] || 0) + 1, o), {}), { 单选: 40, 多选: 40, 判断: 40 });
      assert.equal(realBank.questions[0].answer, 'C'); assert.equal(realBank.questions[0].options[0].text, '2种');
      assert.equal(realBank.questions[20].answer, 'AB'); assert.equal(realBank.questions[40].answerText, 'A. 对');
      assert.equal(realBank.questions[100].answerText, 'B. 错');
      assert(realBank.questions.every(q => q.explanation === ''));
      assert.deepEqual(realBank.questions.map(q => q.number), Array.from({ length: 120 }, (_, i) => i + 1));
      console.log('PASS 真实样本120题120答案，三种题型各40题、全部解析为空');
    }
    for (const format of ['csv', 'json', 'txt']) {
      const promise = tool.waitForEvent('download'); await tool.locator('#' + format).click();
      const file = await promise; await file.saveAs(path.join(qaDir, file.suggestedFilename()));
      assert((await file.failure()) === null);
    }
    await tool.screenshot({ path: path.join(qaDir, 'offline-desktop.png'), fullPage: true });
    await tool.setViewportSize({ width: 390, height: 844 });
    assert(await tool.evaluate(() => document.documentElement.scrollWidth <= window.innerWidth));
    await tool.screenshot({ path: path.join(qaDir, 'offline-mobile.png'), fullPage: true });
    console.log('PASS 离线工具文件导入、三格式下载、无联网、桌面与手机布局');

    // 验证原网页的文档级保存注释可以激活 file: 模式。
    const local = await context.newPage();
    const localHTML = '<!doctype html><!-- saved from url=(0100)http://10.119.67.7/clientcn/exam/local/questions?flag=exercise -->' + fixture('本地练习');
    const localPath = path.join(qaDir, 'local-practice.html'); fs.writeFileSync(localPath, localHTML);
    await local.goto(require('node:url').pathToFileURL(localPath).href);
    const localDownload = local.waitForEvent('download'); await local.addScriptTag({ content: scriptSource });
    assert.equal((await localDownload).suggestedFilename(), '本地练习_题库_3题.csv');
    assert.equal(errors.length, 0, '浏览器不应有控制台/运行时错误：' + errors.join('\n'));
    console.log('PASS 本地保存网页自动识别与浏览器错误检查');
    console.log('验证截图和下载文件：' + qaDir);
  } finally {
    if (browser) await browser.close();
    await new Promise(resolve => server.close(resolve));
  }
})().catch(error => { console.error(error); process.exitCode = 1; });