const nodemailer = require('nodemailer');
require('dotenv').config();

const transporter = nodemailer.createTransport({
  host: process.env.SMTP_HOST || 'smtp.office365.com',
  port: parseInt(process.env.SMTP_PORT || '587', 10),
  secure: process.env.SMTP_SECURE === 'true', // true for 465, false for other ports (587 uses STARTTLS)
  auth: {
    user: process.env.SMTP_USER,
    pass: process.env.SMTP_PASS,
  },
  tls: {
    ciphers: 'SSLv3', // sometimes required for Office365
    rejectUnauthorized: false
  }
});

/**
 * Sends an email using the configured SMTP server.
 * @param {string} to - Recipient email address
 * @param {string} subject - Email subject
 * @param {string} text - Plain text body
 * @param {string} html - HTML body (optional)
 * @returns {Promise<any>} Info object from nodemailer
 */
const sendMail = async (to, subject, text, html = '') => {
  try {
    const info = await transporter.sendMail({
      from: process.env.SMTP_FROM,
      to,
      subject,
      text,
      html
    });
    console.log(`Email sent to ${to}: ${info.messageId}`);
    return info;
  } catch (error) {
    console.error('Error sending email:', error);
    throw error;
  }
};

const sendActivationEmail = async (email, token, baseUrl) => {
  const activationLink = `${baseUrl}/activate?token=${token}`;
  const subject = "Activate your Titan 3D Account";
  const html = `
    <h2>Welcome to Titan 3D!</h2>
    <p>Please click the link below to activate your account:</p>
    <a href="${activationLink}">${activationLink}</a>
    <p>If you did not request this, please ignore this email.</p>
  `;
  const text = `Welcome to Titan 3D! Please navigate to the following link to activate your account: ${activationLink}`;
  return sendMail(email, subject, text, html);
};

const sendPasswordResetEmail = async (email, token, baseUrl) => {
  const resetLink = `${baseUrl}/reset-password?token=${token}`;
  const subject = "Reset your Titan 3D Password";
  const html = `
    <h2>Password Reset Request</h2>
    <p>Please click the link below to securely reset your password:</p>
    <a href="${resetLink}">${resetLink}</a>
    <p>If you did not request this, please ignore this email.</p>
  `;
  const text = `Please navigate to the following link to reset your password: ${resetLink}`;
  return sendMail(email, subject, text, html);
};

module.exports = {
  sendMail,
  sendActivationEmail,
  sendPasswordResetEmail,
  transporter
};