import nodemailer from "nodemailer"

// Lazy-initialized SMTP transport (Mailcow)
let transporter: nodemailer.Transporter | null = null

function getTransporter() {
  if (!transporter && process.env.SMTP_PASS) {
    transporter = nodemailer.createTransport({
      host: process.env.SMTP_HOST || "mail.rmail.online",
      port: parseInt(process.env.SMTP_PORT || "587"),
      secure: false,
      auth: {
        user: process.env.SMTP_USER || "newsletter@cryptocommonsgather.ing",
        pass: process.env.SMTP_PASS,
      },
      tls: { rejectUnauthorized: false },
    })
  }
  return transporter
}

const EMAIL_FROM =
  process.env.EMAIL_FROM ||
  "Crypto Commons Gathering <newsletter@cryptocommonsgather.ing>"

interface PaymentConfirmationData {
  name: string
  email: string
  amountPaid: string
  paymentMethod: string
  contributions: string
  dietary: string
}

export async function sendPaymentConfirmation(
  data: PaymentConfirmationData
): Promise<boolean> {
  const transport = getTransporter()
  if (!transport) {
    console.log("[Email] SMTP not configured, skipping confirmation email")
    return false
  }

  const html = `
    <div style="font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; max-width: 600px; margin: 0 auto; padding: 20px; color: #333;">
      <h1 style="color: #f59e0b; margin-bottom: 8px;">You're In!</h1>
      <p style="font-size: 15px; color: #92400e; margin-top: 0; margin-bottom: 28px; font-style: italic;">Crypto Commons Gathering 2026</p>

      <p>Dear ${data.name},</p>

      <p>Your payment of <strong>${data.amountPaid}</strong> has been confirmed. You are now registered for <strong>Crypto Commons Gathering 2026</strong> in Austria's H&ouml;llental Valley, August 16&ndash;22, 2026.</p>

      <div style="background: #fffbeb; padding: 20px; border-radius: 8px; margin: 24px 0; border-left: 3px solid #f59e0b;">
        <h3 style="margin-top: 0; color: #92400e;">Registration Details</h3>
        <table style="width: 100%; border-collapse: collapse;">
          <tr>
            <td style="padding: 4px 0;"><strong>Amount:</strong></td>
            <td style="padding: 4px 0;">${data.amountPaid}</td>
          </tr>
          <tr>
            <td style="padding: 4px 0;"><strong>Payment:</strong></td>
            <td style="padding: 4px 0;">${data.paymentMethod}</td>
          </tr>
          ${data.dietary ? `<tr><td style="padding: 4px 0;"><strong>Dietary:</strong></td><td style="padding: 4px 0;">${data.dietary}</td></tr>` : ""}
        </table>
      </div>

      ${data.contributions ? `
      <div style="background: #f5f5f0; padding: 16px; border-radius: 8px; margin: 24px 0;">
        <strong style="color: #92400e;">What you're bringing:</strong>
        <p style="margin-bottom: 0; margin-top: 8px;">${data.contributions}</p>
      </div>
      ` : ""}

      <h3 style="color: #92400e;">What's Next?</h3>
      <ul style="line-height: 1.8;">
        <li>Join the <a href="https://t.me/+n5V_wDVKWrk1ZTBh" style="color: #f59e0b;">CCG26 Telegram group</a> to connect with other participants</li>
        <li>Start preparing your session proposals</li>
        <li>Watch for pre-event communications with logistics details</li>
      </ul>

      <p style="margin-top: 32px;">
        See you in the valley,<br>
        <strong>The Crypto Commons Gathering Team</strong>
      </p>

      <hr style="border: none; border-top: 1px solid #ddd; margin: 32px 0;">
      <p style="font-size: 12px; color: #666;">
        You received this email because you registered at cryptocommonsgather.ing.<br>
        <a href="https://cryptocommonsgather.ing">cryptocommonsgather.ing</a>
      </p>
    </div>
  `

  try {
    const info = await transport.sendMail({
      from: EMAIL_FROM,
      to: data.email,
      subject: "Registration Confirmed - Crypto Commons Gathering 2026",
      html,
    })
    console.log(
      `[Email] Payment confirmation sent to ${data.email} (${info.messageId})`
    )
    return true
  } catch (error) {
    console.error("[Email] Failed to send payment confirmation:", error)
    return false
  }
}