// ObsiGate — Floating Action Button (FAB) for the AI Assistant sidebar.
// Always visible in the bottom-right corner; hides while the assistant panel
// is expanded. Clicking it opens the assistant in the context that matches
// the current application state (open documents, or General when none).
import booksLM from './bookslm.js';
import { t } from './i18n.js';
import { safeCreateIcons } from './utils.js';

let _fab = null;

// The panel is visible when it has `.open` without `.hidden`.
function isBooksLmVisible() {
  const panel = document.querySelector('.bookslm-panel');
  return !!(panel && panel.classList.contains('open') && !panel.classList.contains('hidden'));
}

function syncVisibility() {
  if (!_fab) return;
  const visible = isBooksLmVisible();
  _fab.hidden = visible;
  const label = visible ? t('fab.close') : t('fab.open');
  _fab.title = label;
  _fab.setAttribute('aria-label', label);
}

async function onClick() {
  const panel = document.querySelector('.bookslm-panel');
  // Collapsed panel: reveal it instead of reopening.
  if (panel && panel.classList.contains('open') && panel.classList.contains('hidden')) {
    booksLM._toggleSidebar();
    return;
  }
  // Otherwise open (or re-focus) the assistant for the current context.
  await booksLM.openForCurrentContext();
}

export function initAIFab() {
  if (_fab) return;

  const btn = document.createElement('button');
  btn.type = 'button';
  btn.id = 'ai-fab';
  btn.className = 'ai-fab';
  btn.innerHTML = '<i data-lucide="bot" style="width:24px;height:24px"></i>';
  document.body.appendChild(btn);
  _fab = btn;

  btn.addEventListener('click', onClick);
  document.addEventListener('bookslm:opened', syncVisibility);
  document.addEventListener('bookslm:closed', syncVisibility);

  if (typeof safeCreateIcons === 'function') safeCreateIcons();
  syncVisibility();
}

export default initAIFab;