const languageButtons = document.querySelectorAll('[data-lang]');
const translatedNodes = document.querySelectorAll('[data-en][data-zh]');
const translatedInputs = document.querySelectorAll('[data-en-placeholder][data-zh-placeholder]');
const form = document.querySelector('#research-form');
const queryInput = document.querySelector('#company-query');
const research = document.querySelector('#research');
const emptyState = document.querySelector('#research-empty');
const loadingState = document.querySelector('#research-loading');
const errorState = document.querySelector('#research-error');
const resultState = document.querySelector('#research-result');
let currentLanguage = 'en';
let currentResult = null;
const apiOrigin = window.location.hostname.endsWith('.hf.space') ? 'https://robinhood-web-pi.vercel.app' : '';

const copy = {
  en: {
    sector: 'Classification', fiscal: 'Fiscal year end', state: 'Incorporated',
    facts: 'Latest reported facts', filings: 'Recent material filings', period: 'Period', filed: 'Filed',
    source: 'Evidence source', limitations: 'Read before using', live: 'LIVE SEC RECORD',
    noFacts: 'No matching standardized XBRL facts were found for this issuer.',
    noFilings: 'No recent supported filing was found.',
    error: 'The public record could not be opened. Try another U.S. ticker or try again shortly.',
  },
  zh: {
    sector: '行业分类', fiscal: '财年截止', state: '注册地',
    facts: '最近披露指标', filings: '近期重要申报', period: '数据期', filed: '提交日',
    source: '证据来源', limitations: '使用前请阅读', live: 'SEC 实时公开记录',
    noFacts: '未找到该公司的匹配标准化 XBRL 指标。',
    noFilings: '未找到近期受支持的申报。',
    error: '暂时无法打开公开记录。请尝试其他美股代码，或稍后重试。',
  },
};

const element = (tag, className, text) => {
  const node = document.createElement(tag);
  if (className) node.className = className;
  if (text !== undefined) node.textContent = text;
  return node;
};

const formatMoney = (value) => new Intl.NumberFormat(currentLanguage === 'zh' ? 'zh-CN' : 'en-US', {
  style: 'currency', currency: 'USD', notation: 'compact', maximumFractionDigits: 2,
}).format(value);

const renderResult = (data) => {
  const t = copy[currentLanguage];
  const company = data.company;
  resultState.replaceChildren();

  const header = element('header', 'result-header');
  const headingGroup = element('div');
  headingGroup.append(element('p', 'section-label', t.live), element('h2', '', company.name));
  const identity = element('div', 'company-identity');
  identity.append(element('strong', '', company.ticker), element('span', '', company.exchange || '—'), element('span', '', `CIK ${company.cik}`));
  header.append(headingGroup, identity);

  const profile = element('div', 'company-profile');
  [
    [t.sector, company.sic_description || '—'],
    [t.fiscal, company.fiscal_year_end || '—'],
    [t.state, company.state || '—'],
  ].forEach(([label, value]) => {
    const item = element('div');
    item.append(element('span', '', label), element('strong', '', value));
    profile.append(item);
  });

  const factsSection = element('section', 'result-block');
  factsSection.append(element('h3', '', t.facts));
  if (data.metrics.length) {
    const grid = element('div', 'metric-grid');
    data.metrics.forEach((metric) => {
      const card = element('article', 'metric-card');
      const period = metric.period_start ? `${metric.period_start}—${metric.period}` : (metric.period || '—');
      card.append(
        element('span', '', currentLanguage === 'zh' ? metric.label_zh : metric.label_en),
        element('strong', '', formatMoney(metric.value)),
        element('small', '', `${metric.form} · ${t.period} ${period} · ${t.filed} ${metric.filed}`),
      );
      grid.append(card);
    });
    factsSection.append(grid);
  } else {
    factsSection.append(element('p', 'empty-copy', t.noFacts));
  }

  const filingsSection = element('section', 'result-block filings-block');
  filingsSection.append(element('h3', '', t.filings));
  if (data.filings.length) {
    const list = element('div', 'filing-list');
    data.filings.forEach((filing) => {
      const link = element('a', 'filing-row');
      link.href = filing.url;
      link.target = '_blank';
      link.rel = 'noopener';
      link.append(
        element('strong', '', filing.form),
        element('span', '', filing.description),
        element('time', '', filing.filed),
        element('b', '', '↗'),
      );
      list.append(link);
    });
    filingsSection.append(list);
  } else {
    filingsSection.append(element('p', 'empty-copy', t.noFilings));
  }

  const evidence = element('aside', 'evidence-note');
  const evidenceLink = element('a', '', data.source);
  evidenceLink.href = 'https://www.sec.gov/search-filings/edgar-application-programming-interfaces';
  evidenceLink.target = '_blank';
  evidenceLink.rel = 'noopener';
  const retrieved = new Date(data.retrieved_at).toLocaleString(currentLanguage === 'zh' ? 'zh-CN' : 'en-US');
  const sourceLine = element('p');
  sourceLine.append(element('span', '', `${t.source}: `), evidenceLink, document.createTextNode(` · ${retrieved}`));
  evidence.append(sourceLine, element('h3', '', t.limitations), element('p', '', data.limitations[currentLanguage]));

  resultState.append(header, profile, factsSection, filingsSection, evidence);
};

const setLanguage = (language) => {
  currentLanguage = language;
  document.documentElement.lang = language === 'zh' ? 'zh-CN' : 'en';
  translatedNodes.forEach((node) => { node.textContent = node.dataset[language]; });
  translatedInputs.forEach((node) => { node.placeholder = node.dataset[`${language}Placeholder`]; });
  languageButtons.forEach((button) => {
    const active = button.dataset.lang === language;
    button.classList.toggle('active', active);
    button.setAttribute('aria-pressed', String(active));
  });
  if (currentResult) renderResult(currentResult);
};

const runResearch = async (query) => {
  research.setAttribute('aria-busy', 'true');
  emptyState.hidden = true;
  errorState.hidden = true;
  resultState.hidden = true;
  loadingState.hidden = false;
  try {
    const response = await fetch(`${apiOrigin}/api/research?q=${encodeURIComponent(query)}`);
    if (!response.ok) throw new Error(String(response.status));
    currentResult = await response.json();
    renderResult(currentResult);
    resultState.hidden = false;
  } catch (error) {
    currentResult = null;
    errorState.textContent = copy[currentLanguage].error;
    errorState.hidden = false;
  } finally {
    loadingState.hidden = true;
    research.setAttribute('aria-busy', 'false');
    research.scrollIntoView({ behavior: window.matchMedia('(prefers-reduced-motion: reduce)').matches ? 'auto' : 'smooth', block: 'start' });
  }
};

languageButtons.forEach((button) => button.addEventListener('click', () => setLanguage(button.dataset.lang)));
document.querySelectorAll('[data-query]').forEach((button) => button.addEventListener('click', () => {
  queryInput.value = button.dataset.query;
  runResearch(button.dataset.query);
}));
form.addEventListener('submit', (event) => {
  event.preventDefault();
  const query = queryInput.value.trim();
  if (query) runResearch(query);
});

if (!window.matchMedia('(prefers-reduced-motion: reduce)').matches) {
  document.documentElement.classList.add('motion-ready');
  const observer = new IntersectionObserver((entries) => {
    entries.forEach((entry) => {
      if (!entry.isIntersecting) return;
      entry.target.classList.add('visible');
      observer.unobserve(entry.target);
    });
  }, { rootMargin: '0px 0px -10% 0px', threshold: 0.12 });
  document.querySelectorAll('.reveal').forEach((node) => observer.observe(node));
}