// CAPGAIN assistant — answers questions from CAPGAIN's verified law library and points to the book by chapter
// and page. The book's own text is never shown (it is not even shipped to the browser).
import { createEngine } from './answer-engine.mjs?v=642';

const $ = (s) => document.querySelector(s);
const esc = (t) => String(t == null ? '' : t).replace(/[&<>"']/g, (c) => ({ '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;', "'": '&#39;' })[c]);
const safeUrl = (u) => (/^https:\/\//i.test(String(u || '')) ? String(u) : '');
let enginePromise;
function engine() {
  return enginePromise ||= (async () => {
    const book = await fetch('book/book-map.json?v=642', { credentials: 'omit' }).then((r) => (r.ok ? r.json() : null)).catch(() => null);
    for (let i = 0; i < 40 && !(window.CG && window.CG.LAWLIB_DATA); i++) await new Promise((r) => setTimeout(r, 150));
    const records = (window.CG && window.CG.LAWLIB_DATA && window.CG.LAWLIB_DATA.records) || [];
    return createEngine({ records, book });
  })();
}
function endpoint() {
  const c = window.CAPGAIN_BOOK_AI_ENDPOINT;
  return typeof c === 'string' && /^https:\/\//i.test(c) ? c : '';
}
const plainRefs = () => !(window.CG && CG.state && CG.state.prefs && CG.state.prefs.proRefs);
const tidy = (t) => (plainRefs() ? String(t).replace(/[;,]?\s*(?:old\s+)?s\.\d+[A-Za-z-]*(?:\(\d+\))?/g, '').replace(/\(\s*[,;]?\s*\)/g, '').replace(/\s{2,}/g, ' ').replace(/\s+([,.;)])/g, '$1') : String(t));
const STATUS = { 'in force': 'In force', amended: 'Amended', superseded: 'Old law (pre-Apr 2026)', verify: 'Being verified', proposed: 'Proposed', pending: 'Pending' };

function render(a) {
  if (a.kind === 'greeting' || a.kind === 'scope') return `<p>${esc(a.text)}</p>${chips(a.suggestions)}`;
  if (a.kind === 'remote') return `<p>${esc(a.text)}</p>`;
  let h = '';
  if (a.kind === 'unknown') h += `<p>${esc(a.text)}</p>`;
  if (a.calc) h += `<section class="cga-calc"><h3>Your numbers</h3><ul>${a.calc.lines.map((l) => `<li>${esc(tidy(l))}</li>`).join('')}</ul>${a.calc.notes.length ? `<p class="cga-small">${a.calc.notes.map((n) => esc(tidy(n))).join(' ')}</p>` : ''}${a.calc.kind === 'sale' ? '<p class="cga-small">Estimate before any unused basic-exemption adjustment, surcharge on your other income, and reliefs. Not a substitute for advice on your exact facts.</p>' : ''}</section>`;
  if (a.headline) h += `<p class="cga-lead">${esc(tidy(a.headline))}</p>`;
  if (a.points && a.points.length) h += `<ul class="cga-points">${a.points.map((p) => `<li>${esc(p)}</li>`).join('')}</ul>`;
  if (a.caution && a.caution.length) h += `<p class="cga-caution">${a.caution.map(esc).join(' ')}</p>`;
  if (a.law && a.law.length) h += `<div class="cga-block"><h4>The law</h4><ul class="cga-law">${a.law.map((l) => { const u = safeUrl(l.url); const plain = !(window.CG && CG.state && CG.state.prefs && CG.state.prefs.proRefs); const label = plain ? (String(l.title || '').split(/\s[-—–]\s/).slice(1).join(' – ') || l.title) : l.ref; return `<li><span class="cga-ref">${esc(label)}</span> <span class="cga-st cga-st-${esc((l.status || '').replace(/\s+/g, '-'))}">${esc(STATUS[l.status] || l.status || '')}</span>${u ? ` <a href="${esc(u)}" target="_blank" rel="noopener noreferrer">Official source ↗</a>` : ''}</li>`; }).join('')}</ul></div>`;
  if (a.book && a.book.length) h += `<div class="cga-block"><h4>Read more in the CAPGAIN book</h4><ul class="cga-book">${a.book.map((b) => `<li>Chapter ${esc(b.chapter)}${b.chapterTitle ? ` (${esc(b.chapterTitle)})` : ''} · §${esc(b.section)} ${esc(b.title)} · ${esc(b.pages)}</li>`).join('')}</ul></div>`;
  if (a.tools && a.tools.length) h += `<div class="cga-tools">${a.tools.map((t) => `<button type="button" class="cga-chip cga-tool" data-tool="${esc(t.id)}">${esc(t.label)} →</button>`).join('')}</div>`;
  if (a.related && a.related.length) h += `<div class="cga-block"><h4>People also ask</h4>${chips(a.related.map((r) => r.q))}</div>`;
  h += `<p class="cga-small">Law as on ${esc(a.asOf || '15 October 2026')}. General information from CAPGAIN’s verified law library — check your own facts before acting.</p>`;
  return h;
}
const chips = (qs) => (qs && qs.length ? `<div class="cga-related">${qs.map((q) => `<button type="button" class="cga-chip cga-ask" data-q="${esc(q)}">${esc(q)}</button>`).join('')}</div>` : '');

function build() {
  const button = document.createElement('button');
  button.type = 'button'; button.className = 'cg-book-nav'; button.textContent = 'Ask CAPGAIN AI';
  button.setAttribute('aria-haspopup', 'dialog');
  const knowledge = $('#pg-knowledge');
  if (knowledge) knowledge.prepend(button); else document.body.appendChild(button);
  const dialog = document.createElement('dialog');
  dialog.id = 'cg-book-dialog';
  dialog.setAttribute('aria-labelledby', 'cg-book-title');
  dialog.innerHTML = `<div class="cg-book-shell"><header class="cg-book-head"><div><span class="cg-book-eyebrow">CAPGAIN · Property tax assistant</span><h2 id="cg-book-title">Ask CAPGAIN AI</h2><p>Ask in your own words. You get a direct answer from CAPGAIN’s verified law library, your numbers worked out, and where to read more in the book.</p></div><button class="cg-book-close" type="button" aria-label="Close assistant">×</button></header><div class="cg-book-body"><div id="cg-book-conversation" aria-live="polite"></div><form id="cg-book-form"><label for="cg-book-question">Your question</label><div class="cg-book-input"><input id="cg-book-question" maxlength="400" autocomplete="off" enterkeyhint="send" placeholder="e.g. I sold my flat for ₹90 lakh, bought in 2015 for ₹40 lakh. How much tax?"><button type="submit">Ask</button></div></form><p id="cg-book-status" role="status" aria-live="polite"></p><p class="cg-book-note">Runs on your device — your question is not sent anywhere. General information, not legal or tax advice.</p><div id="cg-book-results"></div></div></div>`;
  document.body.appendChild(dialog);
  const input = $('#cg-book-question'); const status = $('#cg-book-status'); const conv = $('#cg-book-conversation');
  const open = (question) => { if (!dialog.open) dialog.showModal(); if (typeof question === 'string' && question.trim()) { input.value = question; ask(question); } else { if (!conv.childElementCount) greet(); input.focus(); } };
  button.onclick = () => open();
  window.CapGainBook = { open };
  const home = $('#pg-home');
  if (home) { const hb = button.cloneNode(true); hb.onclick = () => open(); home.prepend(hb); }
  dialog.querySelector('.cg-book-close').onclick = () => dialog.close();
  dialog.addEventListener('click', (e) => {
    if (e.target === dialog) return dialog.close();
    const q = e.target.closest && e.target.closest('.cga-ask');
    if (q) { input.value = q.dataset.q; return ask(q.dataset.q); }
    const t = e.target.closest && e.target.closest('.cga-tool');
    if (t) { dialog.close(); try { if (window.CG && CG.openCalc) CG.openCalc(t.dataset.tool); else location.hash = '#calculators'; } catch { location.hash = '#calculators'; } }
  });
  const history = [];
  async function greet() { const e = await engine(); add(null, render(e.answer('hello'))); }
  function add(question, html) {
    if (question) { const u = document.createElement('div'); u.className = 'cg-book-turn-user'; u.textContent = question; conv.appendChild(u); }
    const a = document.createElement('div'); a.className = 'cg-book-answer cga-answer'; a.innerHTML = html; conv.appendChild(a);
    a.scrollIntoView({ block: 'start', behavior: 'smooth' });
  }
  let busy = false;
  async function ask(question) {
    question = String(question || '').trim(); if (!question || busy) return;
    busy = true; status.textContent = 'Thinking…'; dialog.querySelector('#cg-book-form button').disabled = true;
    try {
      const e = await engine(); let result = e.answer(question);
      const ep = endpoint();
      if (ep && result.kind !== 'scope') {
        try {
          const r = await fetch(ep, { method: 'POST', headers: { 'content-type': 'application/json' }, body: JSON.stringify({ question, history: history.slice(-6) }) });
          const j = r.ok ? await r.json() : null;
          if (j && typeof j.answer === 'string' && j.answer.trim()) result = { ...result, kind: 'answer', headline: j.answer.slice(0, 2400), points: [] };
        } catch { /* stay with the on-device answer */ }
      }
      history.push({ q: question.slice(0, 300) });
      add(question, render(result)); input.value = ''; status.textContent = '';
    } catch (err) {
      status.textContent = 'The assistant could not load. Please refresh the page and try again.';
    } finally { busy = false; dialog.querySelector('#cg-book-form button').disabled = false; input.focus(); }
  }
  $('#cg-book-form').onsubmit = (e) => { e.preventDefault(); ask(input.value); };

  // The home "Ask CapGain" search box answers through the same engine (smart answer, not a list of library hits).
  // Navigation commands and document uploads still go to the site's own handler.
  window.addEventListener('submit', async (e) => {
    const form = e.target;
    if (!form || form.id !== 'home-ask') return;
    const q = (form.querySelector('#ask-q') || {}).value || '';
    if (!q.trim() || /^(open|go to|show me the|take me|launch)\b/i.test(q.trim())) return;
    const tray = document.getElementById('ask-tray');
    if (tray && tray.querySelector('img, .ask-file, [data-file], li')) return;
    e.preventDefault(); e.stopImmediatePropagation();
    const eng = await engine();
    const probe = eng.answer(q); eng.reset();
    if (probe.kind === 'scope' && window.CG && CG.ai && typeof CG.ai.ask === 'function') { try { CG.ai.ask(q); return; } catch { /* fall through */ } }
    open(q);
  }, true);

  // Relabel the site's entry points to the new assistant.
  const relabel = () => {
    for (const b of document.querySelectorAll('[data-native-action="assistant"] span:not(.cg-native-search-icon)')) if (/book/i.test(b.textContent)) b.textContent = 'Ask CAPGAIN AI — tax, TDS, NRI, RERA';
    const fab = document.getElementById('cg-native-ai-fab');
    if (fab) { fab.setAttribute('aria-label', 'Ask CAPGAIN AI'); const sp = fab.querySelector('span'); if (sp && /book/i.test(sp.textContent)) sp.textContent = 'Ask AI'; }
  };
  relabel(); setTimeout(relabel, 800); setTimeout(relabel, 2500);
  new MutationObserver(() => relabel()).observe(document.body, { childList: true });
}
if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', build, { once: true }); else build();