// Minimal client that sends CSRF, renders assistant HTML, and toggles theme. (jQuery version)

$(function () {
  // Element refs
  const $chat    = $('#chat');
  const $form    = $('#chatForm');
  const $msg     = $('#messageInput');
  const $sys     = $('#systemInput');
  const $reset   = $('#resetBtn');
  const $theme   = $('#themeToggle');

  // Helpers
  function escapeHtmlWithNewlines(s) {
    // jQuery-safe escape via .text(), then convert \n -> <br>
    return $('<div>').text(s).html().replace(/\n/g, '<br>');
  }

  function nowTime() {
    const d = new Date();
    const hh = String(d.getHours()).padStart(2, '0');
    const mm = String(d.getMinutes()).padStart(2, '0');
    return `${hh}:${mm}`;
  }

  function appendUserMessage(text) {
    const html = `
      <div class="msg user">
        <div class="content">${escapeHtmlWithNewlines(text)}</div>
        <div class="time">${nowTime()}</div>
      </div>`;
    $chat.append(html);
    $chat.prop('scrollTop', $chat[0].scrollHeight);
  }

  function appendAssistantHtml(html) {
    const clean = (window.DOMPurify ? DOMPurify.sanitize(html) : html);
    const block = `
      <div class="msg assistant">
        <div class="content">${clean}</div>
        <div class="time">${nowTime()}</div>
      </div>`;
    $chat.append(block);
    $chat.prop('scrollTop', $chat[0].scrollHeight);
  }

  // AJAX POST helper (x-www-form-urlencoded)
  function post(action, data = {}) {
    const csrf = (window.__APP__ && window.__APP__.csrf) || '';
    const payload = new URLSearchParams({ action, csrf, ...data }).toString();
    return $.ajax({
      url: location.pathname,
      method: 'POST',
      data: payload,
      contentType: 'application/x-www-form-urlencoded; charset=UTF-8',
      dataType: 'json'
    });
  }

  // Submit chat
  $form.on('submit', async function (e) {
    e.preventDefault();

    const message = ($msg.val() || '').toString().trim();
    const system  = $sys.length ? ($sys.val() || '').toString().trim() : '';
    if (!message) return;

    appendUserMessage(message);
    $msg.val('').focus();

    try {
      const res = await post('chat', { message, system });
      if (res.ok) {
        appendAssistantHtml(res.reply_html || escapeHtmlWithNewlines(res.reply || ''));
      } else {
        appendAssistantHtml(`<p class="text-danger">Error: ${res.error || 'Unknown'}</p>`);
      }
    } catch (err) {
      appendAssistantHtml(`<p class="text-danger">Network error</p>`);
    }
  });

  // Reset chat
  $reset.on('click', async function () {
    try {
      const res = await post('reset', {});
      if (res.ok) {
        $chat.html('<div class="text-secondary">Start the conversation below…</div>');
      }
    } catch (_) { /* ignore */ }
  });

  // Theme toggle
  $theme.on('click', async function () {
    const current = (window.__APP__ && window.__APP__.theme) || 'dark';
    const next = current === 'dark' ? 'light' : 'dark';
    try {
      const res = await post('set_theme', { theme: next });
      if (res.ok) {
        document.documentElement.setAttribute('data-theme', next);
        if (window.__APP__) window.__APP__.theme = next;
      }
    } catch (_) { /* ignore */ }
  });

  // With "enter" key press, send message (Shift+Enter => newline)
  $msg.on('keydown', function (e) {
    if (e.key === 'Enter' && !e.shiftKey) {
      e.preventDefault();
      $form.trigger('submit');
    }
  });
});

  // ========= Vanilla JS Page Switching (fixed) =========
  (function () {
    const navLinks = document.querySelectorAll('.nav-tab .nav-link[data-page]');
    const pages = document.querySelectorAll('#pageWrapper .page');
    const DURATION = 200; // keep in sync with CSS

    function getActivePage() {
      return document.querySelector('#pageWrapper .page.active');
    }

    function setActiveNav(targetId) {
      navLinks.forEach(a => {
        const isActive = a.getAttribute('data-page') === targetId;
        a.classList.toggle('active', isActive);
        a.setAttribute('aria-current', isActive ? 'page' : 'false');
      });
    }

    function showPage(targetId) {
      const current = getActivePage();
      const next = document.getElementById(targetId);
      if (!next || current === next) return;

      // Prepare next: visible container, but still transparent
      next.classList.add('active'); // display:block; opacity:0

      // Fade-in next on the next frame
      requestAnimationFrame(() => {
        next.classList.add('show'); // opacity -> 1 (transition)
      });

      // Fade-out current (if any)
      if (current) {
        current.classList.remove('show'); // opacity -> 0 (transition)

        let cleaned = false;
        const cleanup = () => {
          if (cleaned) return;
          cleaned = true;
          current.classList.remove('active');
          current.removeEventListener('transitionend', onEnd);
        };

        const onEnd = (e) => {
          if (e.target === current && e.propertyName === 'opacity') {
            cleanup();
          }
        };

        current.addEventListener('transitionend', onEnd);
        // Fallback in case transitionend doesn't fire (reduced motion, etc.)
        setTimeout(cleanup, DURATION + 50);
      }

      setActiveNav(targetId);
      history.replaceState(null, '', '#' + targetId);
    }

    // Click handlers
    navLinks.forEach(link => {
      link.addEventListener('click', (ev) => {
        ev.preventDefault();
        const targetId = link.getAttribute('data-page');
        showPage(targetId);
      });
    });

    // Initial page from hash
    const initial = (location.hash || '#chat').slice(1);
    if (initial !== 'chat' && document.getElementById(initial)) {
      showPage(initial);
    } else {
      setActiveNav('chat');
    }
  })();