// /utils/senders/emailSender.js

const nodemailer = require('nodemailer');
const config = require('../../config/config');
const logger = require('../logger');
const { isMessagingChannelEnabled } = require('../../components/settings/messagingFlags');

let transporter = null;

const getTransporter = () => {
  if (!transporter) {
    transporter = nodemailer.createTransport({
      host: config.SMTP_HOST,
      port: config.SMTP_PORT,
      secure: config.SMTP_PORT === 465,
      auth: config.SMTP_USER ? {
        user: config.SMTP_USER,
        pass: config.SMTP_PASS
      } : undefined
    });
  }
  return transporter;
};

const sendEmail = async ({ to, subject, body, html }) => {
  try {
    if (!to) throw new Error('Recipient email is required');

    if (!(await isMessagingChannelEnabled('email'))) {
      logger.info(`[EmailSender] Skipped (channel disabled) → ${to}`);
      return { skipped: true, reason: 'channel_disabled' };
    }

    const mailOptions = {
      from: config.EMAIL_FROM,
      to,
      subject,
      text: body,
      html: html || `<p>${body}</p>`
    };

    if (config.NODE_ENV === 'test' || !config.SMTP_USER) {
      logger.info(`[EmailSender MOCK] To: ${to} | Subject: ${subject} | Body: ${body}`);
      return { success: true, messageId: `mock_${Date.now()}` };
    }

    const info = await getTransporter().sendMail(mailOptions);
    logger.info(`[EmailSender] Message sent: ${info.messageId} to ${to}`);
    return { success: true, messageId: info.messageId };
  } catch (error) {
    logger.error(`[EmailSender ERROR] Failed to send email to ${to}: ${error.message}`);
    throw error;
  }
};

module.exports = {
  sendEmail
};