/**
 * Helpers pour la manipulation de données Firestore
 */
const admin = require('firebase-admin');

/**
 * Convertit les Timestamps Firestore en ISO strings pour JSON
 */
function serializeTimestamps(data) {
  if (!data) return data;

  const result = { ...data };

  for (const key in result) {
    if (result[key] && result[key].toDate && typeof result[key].toDate === 'function') {
      // C'est un Timestamp Firestore
      result[key] = result[key].toDate().toISOString();
    } else if (result[key] && typeof result[key] === 'object' && !Array.isArray(result[key])) {
      // Objet imbriqué
      result[key] = serializeTimestamps(result[key]);
    } else if (Array.isArray(result[key])) {
      // Tableau
      result[key] = result[key].map(item =>
        item && typeof item === 'object' ? serializeTimestamps(item) : item
      );
    }
  }

  return result;
}

/**
 * Convertit les ISO strings en Timestamps Firestore
 */
function deserializeTimestamps(data, timestampFields = []) {
  if (!data) return data;

  const result = { ...data };

  for (const field of timestampFields) {
    if (result[field] && typeof result[field] === 'string') {
      result[field] = admin.firestore.Timestamp.fromDate(new Date(result[field]));
    }
  }

  return result;
}

/**
 * Convertit les références DocumentReference en IDs
 */
function serializeReferences(data) {
  if (!data) return data;

  const result = { ...data };

  for (const key in result) {
    if (result[key] && result[key].path && typeof result[key].path === 'string') {
      // C'est une DocumentReference
      result[key] = result[key].id;
    } else if (Array.isArray(result[key])) {
      result[key] = result[key].map(item => {
        if (item && item.path && typeof item.path === 'string') {
          return item.id;
        }
        return item;
      });
    }
  }

  return result;
}

/**
 * Masque les champs sensibles selon les permissions
 */
function maskSensitiveFields(data, canViewSensitive) {
  if (canViewSensitive) return data;

  const masked = { ...data };

  // Masquer les prix si pas de permission manage_equipment
  delete masked.purchasePrice;
  delete masked.rentalPrice;

  return masked;
}

/**
 * Pagination helper
 */
function paginate(query, limit = 50, startAfter = null) {
  let paginatedQuery = query.limit(limit);

  if (startAfter) {
    paginatedQuery = paginatedQuery.startAfter(startAfter);
  }

  return paginatedQuery;
}

/**
 * Filtre les événements annulés
 */
function filterCancelledEvents(events) {
  return events.filter(event => event.status !== 'CANCELLED');
}

module.exports = {
  serializeTimestamps,
  deserializeTimestamps,
  serializeReferences,
  maskSensitiveFields,
  paginate,
  filterCancelledEvents,
};