const nodemailer = require('nodemailer');

// Build a transport from the resolved SMTP settings, or null if not configured.
function buildTransport(smtp) {
  if (!smtp.host) return null;
  const port = Number(smtp.port) || 587;
  return nodemailer.createTransport({
    host: smtp.host,
    port,
    secure: smtp.secure === true || smtp.secure === 'true' || port === 465,
    auth: smtp.user ? { user: smtp.user, pass: smtp.pass } : undefined,
  });
}

// smtp: { host, port, secure, user, pass, from }
async function sendPasswordReset(smtp, to, link) {
  const transport = buildTransport(smtp);
  if (!transport) throw new Error('SMTP is not configured.');
  await transport.sendMail({
    from: smtp.from || smtp.user,
    to,
    subject: 'Printhive password reset',
    text: `Reset your Printhive password using this link (valid for 1 hour):\n\n${link}\n\nIf you didn't request this, you can ignore this email.`,
    html: `<p>Reset your Printhive password using this link (valid for 1 hour):</p>
           <p><a href="${link}">${link}</a></p>
           <p style="color:#888">If you didn't request this, you can ignore this email.</p>`,
  });
}

module.exports = { buildTransport, sendPasswordReset };