/**
 * Email service powered by Resend.
 *
 * Required env vars:
 *   RESEND_API_KEY
 *   STORE_EMAIL_FROM   (e.g. "orders@yourstore.com")
 *   STORE_NAME         (e.g. "My Store")
 */

import { Resend } from "resend";

let _resend: Resend | null = null;

function getResend(): Resend {
  if (!_resend) {
    if (!process.env.RESEND_API_KEY) {
      throw new Error("RESEND_API_KEY is not configured");
    }
    _resend = new Resend(process.env.RESEND_API_KEY);
  }
  return _resend;
}

const FROM = process.env.STORE_EMAIL_FROM || "noreply@yourstore.com";
const STORE_NAME = process.env.STORE_NAME || "My Store";

export async function sendMagicLink(email: string, token: string, baseUrl: string) {
  const link = `${baseUrl}/account/verify?token=${token}`;
  try {
    await getResend().emails.send({
      from: FROM,
      to: email,
      subject: `Sign in to ${STORE_NAME}`,
      html: `
        <p>Click the link below to sign in to ${STORE_NAME}. This link expires in 15 minutes.</p>
        <p><a href="${link}" style="font-weight:bold">Sign In →</a></p>
        <p style="color:#888;font-size:12px">If you didn't request this, you can safely ignore this email.</p>
      `,
    });
  } catch (err) {
    console.error("[email] sendMagicLink failed:", err);
  }
}

export async function sendOrderConfirmation(params: {
  email: string;
  orderNumber: string;
  total: string;
  items: Array<{ title: string; variantTitle?: string; quantity: number; price: string }>;
  shippingAddress?: any;
}) {
  const itemsHtml = params.items
    .map(
      (item) => `<tr>
      <td style="padding:8px 0;border-bottom:1px solid #f0f0f0">${item.title}${item.variantTitle ? ` — ${item.variantTitle}` : ""}</td>
      <td style="padding:8px 0;border-bottom:1px solid #f0f0f0;text-align:center">${item.quantity}</td>
      <td style="padding:8px 0;border-bottom:1px solid #f0f0f0;text-align:right">$${item.price}</td>
    </tr>`
    )
    .join("");

  const addr = params.shippingAddress;
  const addrHtml = addr
    ? `<p><strong>Ship to:</strong><br>${addr.firstName} ${addr.lastName}<br>${addr.address1}${addr.address2 ? `, ${addr.address2}` : ""}<br>${addr.city}, ${addr.state} ${addr.zip}</p>`
    : "";

  try {
    await getResend().emails.send({
      from: FROM,
      to: params.email,
      subject: `Order confirmed — #${params.orderNumber}`,
      html: `
        <div style="font-family:sans-serif;max-width:560px;margin:auto">
          <h2 style="color:#333">Thanks for your order!</h2>
          <p>Order <strong>#${params.orderNumber}</strong> has been received and is being processed.</p>
          <table width="100%" cellpadding="0" cellspacing="0">
            <thead>
              <tr>
                <th style="text-align:left;padding-bottom:8px;border-bottom:2px solid #eee">Item</th>
                <th style="text-align:center;padding-bottom:8px;border-bottom:2px solid #eee">Qty</th>
                <th style="text-align:right;padding-bottom:8px;border-bottom:2px solid #eee">Price</th>
              </tr>
            </thead>
            <tbody>${itemsHtml}</tbody>
            <tfoot>
              <tr>
                <td colspan="2" style="padding-top:12px;text-align:right;font-weight:bold">Total</td>
                <td style="padding-top:12px;text-align:right;font-weight:bold">$${params.total}</td>
              </tr>
            </tfoot>
          </table>
          ${addrHtml}
          <p style="color:#888;font-size:12px;margin-top:32px">Thank you for shopping with ${STORE_NAME}.</p>
        </div>
      `,
    });
  } catch (err) {
    console.error("[email] sendOrderConfirmation failed:", err);
  }
}

export async function sendShippingNotification(params: {
  email: string;
  orderNumber: string;
  trackingNumber: string;
  trackingCarrier?: string;
}) {
  try {
    await getResend().emails.send({
      from: FROM,
      to: params.email,
      subject: `Your order #${params.orderNumber} has shipped`,
      html: `
        <p>Great news! Your ${STORE_NAME} order <strong>#${params.orderNumber}</strong> is on its way.</p>
        <p><strong>Tracking number:</strong> ${params.trackingNumber}${params.trackingCarrier ? ` (${params.trackingCarrier})` : ""}</p>
        <p style="color:#888;font-size:12px">Thank you for your order!</p>
      `,
    });
  } catch (err) {
    console.error("[email] sendShippingNotification failed:", err);
  }
}