const db = require('../../config/db');
const fs = require('fs/promises');
const path = require('path');

const chainMetadataDir = path.resolve(process.cwd(), 'storage', 'certificates', 'metadata');
const chainMetadataFile = path.join(chainMetadataDir, 'chain-status.json');

const readChainMetadata = async () => {
  try {
    const raw = await fs.readFile(chainMetadataFile, 'utf8');
    return JSON.parse(raw);
  } catch {
    return {};
  }
};

const writeChainMetadata = async (data) => {
  await fs.mkdir(chainMetadataDir, { recursive: true });
  await fs.writeFile(chainMetadataFile, JSON.stringify(data, null, 2), 'utf8');
};

const create = async ({ userId, alias, filename, storagePath, subjectCn, issuerCn, validFrom, validTo, serialNumber }) => {
  const [result] = await db.execute(
    `INSERT INTO certificates (user_id, alias, filename, storage_path, subject_cn, issuer_cn, valid_from, valid_to, serial_number)
     VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`,
    [userId, alias, filename, storagePath, subjectCn || null, issuerCn || null, validFrom || null, validTo || null, serialNumber || null]
  );
  return result.insertId;
};

const findByUser = async (userId) => {
  const [rows] = await db.execute(
    'SELECT id, user_id, alias, filename, subject_cn, issuer_cn, valid_from, valid_to, serial_number, is_active, created_at FROM certificates WHERE user_id = ? ORDER BY created_at DESC',
    [userId]
  );
  return rows;
};

const findById = async (id) => {
  const [rows] = await db.execute('SELECT * FROM certificates WHERE id = ?', [id]);
  return rows[0] || null;
};

const deactivate = async (id) => {
  await db.execute('UPDATE certificates SET is_active = 0 WHERE id = ?', [id]);
};

const remove = async (id) => {
  await db.execute('DELETE FROM certificates WHERE id = ?', [id]);
};

const saveChainStatus = async (certId, metadata) => {
  const current = await readChainMetadata();
  current[String(certId)] = metadata;
  await writeChainMetadata(current);
};

const getChainStatus = async (certId) => {
  const current = await readChainMetadata();
  return current[String(certId)] || null;
};

const removeChainStatus = async (certId) => {
  const current = await readChainMetadata();
  delete current[String(certId)];
  await writeChainMetadata(current);
};

module.exports = {
  create,
  findByUser,
  findById,
  deactivate,
  remove,
  saveChainStatus,
  getChainStatus,
  removeChainStatus,
};