import { Resend } from 'resend';
import nodemailer from 'nodemailer';
import * as dotenv from 'dotenv';

// Load environment variables
dotenv.config();

const resend = new Resend(process.env.RESEND_API_KEY);

function smtpEnabled(): boolean {
  return Boolean(
    process.env.SMTP_HOST &&
      process.env.SMTP_USER &&
      process.env.SMTP_PASS
  );
}

async function testEmailSending() {
  console.log('🧪 Testing email sending configuration...\n');
  
  // Check environment variables
  console.log('📋 Environment Variables:');
  console.log('  EMAIL_PROVIDER:', process.env.EMAIL_PROVIDER || 'smtp (default)');
  console.log('  SMTP_HOST:', process.env.SMTP_HOST || '❌ NOT SET');
  console.log('  SMTP_PORT:', process.env.SMTP_PORT || '465 (default)');
  console.log('  SMTP_SECURE:', process.env.SMTP_SECURE || 'true (default)');
  console.log('  SMTP_USER:', process.env.SMTP_USER || '❌ NOT SET');
  console.log('  SMTP_FROM_EMAIL:', process.env.SMTP_FROM_EMAIL || '❌ NOT SET');
  console.log('  RESEND_API_KEY:', process.env.RESEND_API_KEY ? `${process.env.RESEND_API_KEY.substring(0, 10)}...` : '❌ NOT SET');
  console.log('  RESEND_FROM_EMAIL:', process.env.RESEND_FROM_EMAIL || '❌ NOT SET');
  console.log('  NEXTAUTH_URL:', process.env.NEXTAUTH_URL || '❌ NOT SET');
  console.log('');

  const toEmail = process.env.TEST_EMAIL_TO || process.env.SMTP_USER || process.env.RESEND_FROM_EMAIL;
  if (!toEmail) {
    console.error('❌ Set TEST_EMAIL_TO or SMTP_USER in .env to run this test.');
    process.exit(1);
  }

  if (smtpEnabled()) {
    console.log('📤 Attempting SMTP test first...');
    try {
      const transporter = nodemailer.createTransport({
        host: process.env.SMTP_HOST,
        port: Number(process.env.SMTP_PORT || 465),
        secure: (process.env.SMTP_SECURE || 'true').toLowerCase() === 'true',
        auth: {
          user: process.env.SMTP_USER,
          pass: process.env.SMTP_PASS,
        },
      });

      const smtpFromEmail = process.env.SMTP_FROM_EMAIL || process.env.SMTP_USER!;
      const smtpFromName = process.env.SMTP_FROM_NAME;
      const smtpReplyTo = process.env.SMTP_REPLY_TO || smtpFromEmail;
      const smtpFrom = smtpFromName
        ? `${smtpFromName} <${smtpFromEmail}>`
        : smtpFromEmail;

      const info = await transporter.sendMail({
        from: smtpFrom,
        to: toEmail,
        replyTo: smtpReplyTo,
        subject: 'SMTP test from PunimTag',
        text: 'SMTP test email from PunimTag viewer frontend.',
      });

      console.log('✅ SMTP test sent successfully');
      console.log('   Message ID:', info.messageId);
      process.exit(0);
    } catch (smtpError: any) {
      console.error('⚠️  SMTP test failed, will try Resend fallback.');
      console.error('   SMTP error:', smtpError.message);
    }
  } else {
    console.log('ℹ️  SMTP config not set, skipping SMTP test.');
  }

  if (!process.env.RESEND_API_KEY || !process.env.RESEND_FROM_EMAIL) {
    console.error('❌ Resend fallback not configured (RESEND_API_KEY/RESEND_FROM_EMAIL missing).');
    process.exit(1);
  }

  const resendFrom = process.env.RESEND_FROM_EMAIL.trim().replace(/^["']|["']$/g, '');
  console.log('📤 Attempting Resend fallback test...');
  try {
    const result = await resend.emails.send({
      from: resendFrom,
      to: toEmail,
      subject: 'Resend fallback test from PunimTag',
      html: '<p>Resend fallback test email from PunimTag viewer frontend.</p>',
    });
    if (result.error) {
      throw new Error(result.error.message || 'Unknown Resend API error');
    }
    console.log('✅ Resend fallback test sent successfully');
    console.log('   Email ID:', result.data?.id);
  } catch (error: any) {
    console.error('❌ Resend fallback failed:', error.message);
    process.exit(1);
  }
}

testEmailSending();