/* ObsiGate — Command Palette (Ctrl+P)
   Quick file opener and command runner.
   Inspired by VS Code's Ctrl+P / Ctrl+Shift+P.
*/
import { api } from './auth.js';
import { openFile } from './viewer.js';
import { showToast, toggleTheme } from './ui.js';
import { state } from './state.js';

// ── Helper: trigger goHome by clicking the logo ──
function triggerGoHome() {
  const logo = document.getElementById('header-logo');
  if (logo) logo.click();
}

// ── DOM cache (created in open) ──
let _overlay = null;
let _input = null;
let _results = null;
let _mode = 'files'; // 'files' | 'commands'
let _selectedIndex = 0;
let _searchTimeout = null;
let _lastResults = [];

// ── Available commands ──
const COMMANDS = [
  { id: 'home', label: '🏠 Accueil', description: 'Retour à l\'accueil', action: () => { close(); triggerGoHome(); } },
  { id: 'theme', label: '🌓 Changer le thème', description: 'Basculer clair/sombre', action: () => { close(); toggleTheme(); } },
  { id: 'reindex', label: '🔄 Réindexer', description: 'Forcer la réindexation complète', action: async () => { close(); try { await api('/api/index/reload'); showToast('Index rechargé', 'success'); } catch { showToast('Erreur de réindexation', 'error'); } } },
  { id: 'help', label: '❓ Aide', description: 'Ouvrir l\'aide', action: () => { close(); const helpBtn = document.getElementById('header-help-btn'); if (helpBtn) helpBtn.click(); } },
  { id: 'config', label: '⚙️ Configuration', description: 'Ouvrir les paramètres', action: () => { close(); const btn = document.getElementById('config-open-btn'); if (btn) btn.click(); } },
];

// ── Create DOM structure ──
function createDOM() {
  if (_overlay) return;

  _overlay = document.createElement('div');
  _overlay.className = 'command-palette-overlay';
  _overlay.innerHTML = `
    <div class="command-palette">
      <div class="cp-header">
        <input type="text" class="cp-input" placeholder="Rechercher un fichier... (tapez > pour les commandes)" spellcheck="false" autocomplete="off">
        <span class="cp-hint">Alt+P</span>
      </div>
      <div class="cp-results"></div>
      <div class="cp-footer">
        <span>↑↓ naviguer</span>
        <span>↵ ouvrir</span>
        <span>Esc fermer</span>
      </div>
    </div>
  `;

  _input = _overlay.querySelector('.cp-input');
  _results = _overlay.querySelector('.cp-results');

  // Click outside to close (on overlay, not the palette dialog)
  _overlay.addEventListener('click', (e) => {
    if (e.target === _overlay) close();
  });

  // Keyboard events
  _input.addEventListener('keydown', onKeyDown);
  _input.addEventListener('input', onInput);

  document.body.appendChild(_overlay);
}

// ── Open / Close ──
export function open(initialQuery = '') {
  createDOM();
  _overlay.classList.add('active');
  _input.value = initialQuery;
  _mode = initialQuery.startsWith('>') ? 'commands' : 'files';
  _selectedIndex = 0;
  _lastResults = [];
  _results.innerHTML = '';
  _input.focus();
  // Trigger initial search
  onInput();
}

export function close() {
  if (!_overlay) return;
  _overlay.classList.remove('active');
  if (_searchTimeout) clearTimeout(_searchTimeout);
  _searchTimeout = null;
  // Restore focus
  const searchInput = document.querySelector('.search-input');
  if (searchInput) searchInput.focus();
}

function isOpen() {
  return _overlay && _overlay.classList.contains('active');
}

// ── Input handler ──
function onInput() {
  const val = _input.value;

  // Detect mode change
  const newMode = val.startsWith('>') ? 'commands' : 'files';
  if (newMode !== _mode) {
    _mode = newMode;
    _input.placeholder = _mode === 'commands'
      ? 'Tapez une commande...'
      : 'Rechercher un fichier... (tapez > pour les commandes)';
  }

  if (_searchTimeout) clearTimeout(_searchTimeout);
  _searchTimeout = setTimeout(() => {
    _searchTimeout = null;
    if (_mode === 'commands') {
      searchCommands(val.slice(1).trim());
    } else {
      searchFiles(val.trim());
    }
  }, 150);
}

// ── Search files (via /api/suggest) ──
async function searchFiles(query) {
  if (!query) {
    _results.innerHTML = '<div class="cp-empty">Commencez à taper pour chercher un fichier</div>';
    _lastResults = [];
    return;
  }

  try {
    const data = await api(`/api/suggest?q=${encodeURIComponent(query)}&vault=all`);
    const suggestions = data.suggestions || [];
    _lastResults = suggestions.map(s => ({
      type: 'file',
      vault: s.vault,
      path: s.path,
      title: s.title,
      label: s.title || s.path.split('/').pop(),
      sublabel: `${s.vault}/${s.path}`,
    }));
    renderResults();
  } catch {
    _results.innerHTML = '<div class="cp-empty cp-error">Erreur de recherche</div>';
  }
}

// ── Search commands ──
function searchCommands(query) {
  if (!query) {
    _lastResults = COMMANDS.map(c => ({ type: 'command', ...c }));
    renderResults();
    return;
  }

  const lower = query.toLowerCase();
  _lastResults = COMMANDS
    .filter(c => c.label.toLowerCase().includes(lower) || c.description.toLowerCase().includes(lower))
    .map(c => ({ type: 'command', ...c }));
  renderResults();
}

// ── Render results list ──
function renderResults() {
  _selectedIndex = 0;

  if (_lastResults.length === 0) {
    _results.innerHTML = '<div class="cp-empty">Aucun résultat</div>';
    return;
  }

  _results.innerHTML = _lastResults.map((item, i) => `
    <div class="cp-item ${i === 0 ? 'cp-selected' : ''}" data-index="${i}">
      <div class="cp-item-label">${escapeHtml(item.label)}</div>
      <div class="cp-item-sublabel">${escapeHtml(item.sublabel || item.description || '')}</div>
    </div>
  `).join('');

  // Click handler
  _results.querySelectorAll('.cp-item').forEach(el => {
    el.addEventListener('click', () => {
      const idx = parseInt(el.dataset.index);
      executeItem(idx);
    });
    el.addEventListener('mouseenter', () => {
      document.querySelectorAll('.cp-item').forEach(e => e.classList.remove('cp-selected'));
      el.classList.add('cp-selected');
      _selectedIndex = parseInt(el.dataset.index);
    });
  });

  scrollToSelected();
}

// ── Keyboard navigation ──
function onKeyDown(e) {
  const items = _results.querySelectorAll('.cp-item');

  if (e.key === 'Escape') {
    e.preventDefault();
    close();
  } else if (e.key === 'Enter') {
    e.preventDefault();
    executeItem(_selectedIndex);
  } else if (e.key === 'ArrowDown') {
    e.preventDefault();
    _selectedIndex = Math.min(_selectedIndex + 1, _lastResults.length - 1);
    updateSelection(items);
  } else if (e.key === 'ArrowUp') {
    e.preventDefault();
    _selectedIndex = Math.max(_selectedIndex - 1, 0);
    updateSelection(items);
  } else if (e.key === 'Tab') {
    e.preventDefault();
    // Switch between files/commands mode
    if (_mode === 'files') {
      _input.value = '> ';
      // Move cursor to end
      setTimeout(() => {
        _input.selectionStart = _input.selectionEnd = _input.value.length;
      }, 0);
    } else {
      _input.value = '';
    }
    onInput();
  }
}

function updateSelection(items) {
  items.forEach((el, i) => {
    el.classList.toggle('cp-selected', i === _selectedIndex);
  });
  scrollToSelected();
}

function scrollToSelected() {
  const selected = _results.querySelector('.cp-selected');
  if (selected) {
    selected.scrollIntoView({ block: 'nearest' });
  }
}

// ── Execute ──
function executeItem(index) {
  const item = _lastResults[index];
  if (!item) return;

  if (item.type === 'file') {
    close();
    openFile(item.vault, item.path);
  } else if (item.type === 'command') {
    item.action();
  }
}

// ── HTML escaping ──
function escapeHtml(str) {
  if (!str) return '';
  return String(str)
    .replace(/&/g, '&amp;')
    .replace(/</g, '&lt;')
    .replace(/>/g, '&gt;')
    .replace(/"/g, '&quot;');
}

// ── Init: Register global keyboard shortcut ──
export function initCommandPalette() {
  document.addEventListener('keydown', (e) => {
    // Alt+P — open palette (Alt+Shift+P for command mode)
    if (e.altKey && !e.ctrlKey && !e.metaKey && e.key === 'p') {
      e.preventDefault();
      if (isOpen()) {
        close();
      } else {
        open('');
      }
    }
    // Alt+Shift+P — open in command mode
    if (e.altKey && e.shiftKey && !e.ctrlKey && !e.metaKey && e.key === 'p') {
      e.preventDefault();
      if (isOpen()) {
        close();
      } else {
        open('> ');
      }
    }
  });
}