const fs = require('fs');
const path = require('path');
const { getCentralPool } = require('../db/central');
const { hashPassword } = require('../utils/password');

function splitSql(sql) {
  return sql
    .split(/;\s*\n/)
    .map((s) => s.trim())
    .filter((s) => s.length);
}

async function runSqlStatements(pool, sqlText) {
  const statements = splitSql(sqlText);
  for (const stmt of statements) {
    await pool.query(stmt);
  }
}

async function provisionTenant({ name, code, dbName, dbHost, dbPort, dbUser, dbPass, adminName, adminEmail, adminPassword, startDate, endDate }) {
  const central = getCentralPool();

  await central.query(
    'INSERT INTO companies (name, code, start_date, end_date, db_host, db_port, db_name, db_user, db_pass) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)',
    [name, code, startDate || null, endDate || null, dbHost, dbPort, dbName, dbUser, dbPass]
  );

  await central.query(`CREATE DATABASE IF NOT EXISTS \`${dbName}\` CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci`);

  const mysql = require('mysql2/promise');
  const tenantPool = mysql.createPool({
    host: dbHost,
    port: dbPort,
    user: dbUser,
    password: dbPass,
    database: dbName,
    waitForConnections: true,
    connectionLimit: 5
  });

  const schemaSql = fs.readFileSync(path.join(__dirname, '../sql/tenant_schema.sql'), 'utf8');
  const seedSql = fs.readFileSync(path.join(__dirname, '../sql/seed_questions.sql'), 'utf8');

  await runSqlStatements(tenantPool, schemaSql);
  await runSqlStatements(tenantPool, seedSql);

  const passwordHash = await hashPassword(adminPassword);
  await tenantPool.query(
    'INSERT INTO admins (name, email, password_hash, role, status) VALUES (?, ?, ?, "admin", "active")',
    [adminName, adminEmail, passwordHash]
  );

  await tenantPool.end();
  return true;
}

module.exports = { provisionTenant };