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

const saveEvent = async (event) => {
  try {
    await db.execute(
      'INSERT INTO audit_logs (type, user_id, email, ip, user_agent, metadata) VALUES (?, ?, ?, ?, ?, ?)',
      [
        event.type,
        event.userId || null,
        event.email || null,
        event.ip || null,
        event.userAgent || null,
        event.metadata ? JSON.stringify(event.metadata) : null,
      ]
    );
  } catch (err) {
    // Fallback to file log if DB fails
    try {
      const logsDir = path.resolve(process.cwd(), 'logs');
      await fs.mkdir(logsDir, { recursive: true });
      await fs.appendFile(
        path.resolve(logsDir, 'audit.log'),
        `${JSON.stringify({ ...event, _fallback: true })}\n`
      );
    } catch {
      // Silent
    }
  }
};

const getEvents = async ({ type, userId, limit = 100, offset = 0, types = [] } = {}) => {
  let sql = 'SELECT * FROM audit_logs WHERE 1=1';
  let countSql = 'SELECT COUNT(*) AS total FROM audit_logs WHERE 1=1';
  const params = [];
  const countParams = [];
  if (type) { sql += ' AND type = ?'; params.push(type); }
  if (type) { countSql += ' AND type = ?'; countParams.push(type); }
  if (types.length > 0) {
    const placeholders = types.map(() => '?').join(', ');
    sql += ` AND type IN (${placeholders})`;
    countSql += ` AND type IN (${placeholders})`;
    params.push(...types);
    countParams.push(...types);
  }
  if (userId) {
    sql += ' AND user_id = ?';
    countSql += ' AND user_id = ?';
    params.push(userId);
    countParams.push(userId);
  }
  sql += ' ORDER BY created_at DESC LIMIT ? OFFSET ?';
  params.push(limit, offset);
  const [rows] = await db.execute(sql, params);
  const [countRows] = await db.execute(countSql, countParams);
  return {
    rows,
    total: countRows[0]?.total || 0,
  };
};

const deleteEventsByUserId = async (userId) => {
  const [result] = await db.execute('DELETE FROM audit_logs WHERE user_id = ?', [userId]);
  return result.affectedRows || 0;
};

module.exports = { saveEvent, getEvents, deleteEventsByUserId };