import { components } from "./_generated/api";
import { Resend } from "@convex-dev/resend";
import { internalMutation } from "./_generated/server";
import { v } from "convex/values";

// ─── Component instance ───────────────────────────────────────────────────────

export const resend = new Resend(components.resend, {
  // Set testMode: false once you have a verified Resend domain and want to
  // deliver to real addresses. While testMode is true, only Resend's own test
  // addresses (e.g. delivered@resend.dev) will actually receive mail.
  testMode: false,
});

// Update this once your sending domain is verified in Resend.
const FROM = "The Pet Loft <no-reply@thepetloft.co.uk>";

// ─── HTML helpers ─────────────────────────────────────────────────────────────

function base(body: string): string {
  return `
    <div style="font-family:sans-serif;max-width:600px;margin:0 auto;background:#f0f8f7;padding:24px">
      <div style="background:#236f6b;padding:20px 24px;border-radius:8px 8px 0 0">
        <h1 style="color:#fff;margin:0;font-size:22px;letter-spacing:-0.5px">The Pet Loft</h1>
      </div>
      <div style="background:#fff;padding:32px 24px;border-radius:0 0 8px 8px;color:#1a2e2d">
        ${body}
      </div>
      <p style="color:#1a2e2d;font-size:12px;text-align:center;margin-top:16px;opacity:0.6">
        &copy; ${new Date().getFullYear()} The Pet Loft. All rights reserved.
      </p>
    </div>
  `;
}

function formatPrice(amountInSmallestUnit: number, currency: string): string {
  return new Intl.NumberFormat("en-GB", {
    style: "currency",
    currency: currency.toUpperCase(),
  }).format(amountInSmallestUnit / 100);
}

function btn(href: string, label: string): string {
  return `<a href="${href}" style="display:inline-block;background:#38a99f;color:#fff;padding:12px 24px;border-radius:6px;text-decoration:none;font-weight:bold;margin-top:16px">${label}</a>`;
}

// ─── Order confirmation ───────────────────────────────────────────────────────

export const sendOrderConfirmation = internalMutation({
  args: {
    to: v.string(),
    firstName: v.string(),
    orderNumber: v.string(),
    total: v.number(),
    currency: v.string(),
    items: v.array(
      v.object({
        productName: v.string(),
        variantName: v.string(),
        quantity: v.number(),
        unitPrice: v.number(),
      }),
    ),
    shippingAddress: v.object({
      fullName: v.string(),
      addressLine1: v.string(),
      city: v.string(),
      postalCode: v.string(),
      country: v.string(),
    }),
  },
  handler: async (ctx, args) => {
    const rows = args.items
      .map(
        (item) => `
        <tr>
          <td style="padding:8px 0;border-bottom:1px solid #f0f8f7">
            <strong>${item.productName}</strong><br>
            <span style="font-size:13px;opacity:0.7">${item.variantName}</span>
          </td>
          <td style="padding:8px 0;border-bottom:1px solid #f0f8f7;text-align:center">×${item.quantity}</td>
          <td style="padding:8px 0;border-bottom:1px solid #f0f8f7;text-align:right;color:#236f6b;font-weight:bold">
            ${formatPrice(item.unitPrice * item.quantity, args.currency)}
          </td>
        </tr>`,
      )
      .join("");

    const addr = args.shippingAddress;

    const html = base(`
      <h2 style="color:#236f6b;margin-top:0">Order confirmed!</h2>
      <p>Hi ${args.firstName}, thank you for your order. We&rsquo;re getting it ready now.</p>
      <p style="margin-bottom:4px"><strong>Order:</strong> ${args.orderNumber}</p>

      <table style="width:100%;border-collapse:collapse;margin:20px 0">
        ${rows}
        <tr>
          <td colspan="2" style="padding:12px 0;font-weight:bold">Total</td>
          <td style="padding:12px 0;text-align:right;color:#236f6b;font-weight:bold;font-size:18px">
            ${formatPrice(args.total, args.currency)}
          </td>
        </tr>
      </table>

      <p style="margin-bottom:4px"><strong>Shipping to:</strong></p>
      <p style="margin:0;line-height:1.6">
        ${addr.fullName}<br>
        ${addr.addressLine1}<br>
        ${addr.city}, ${addr.postalCode}<br>
        ${addr.country}
      </p>
    `);

    await resend.sendEmail(ctx, {
      from: FROM,
      to: args.to,
      subject: `Order confirmed — ${args.orderNumber}`,
      html,
    });
  },
});

// ─── Shipping confirmation ────────────────────────────────────────────────────

export const sendShippingConfirmation = internalMutation({
  args: {
    to: v.string(),
    firstName: v.string(),
    orderNumber: v.string(),
    trackingNumber: v.string(),
    trackingUrl: v.string(),
    carrier: v.string(),
    estimatedDelivery: v.optional(v.number()),
  },
  handler: async (ctx, args) => {
    const eta = args.estimatedDelivery
      ? `<p><strong>Estimated delivery:</strong> ${new Date(args.estimatedDelivery).toDateString()}</p>`
      : "";

    const html = base(`
      <h2 style="color:#236f6b;margin-top:0">Your order is on its way!</h2>
      <p>Hi ${args.firstName}, <strong>${args.orderNumber}</strong> has been shipped.</p>
      <p><strong>Carrier:</strong> ${args.carrier}</p>
      <p><strong>Tracking number:</strong> ${args.trackingNumber}</p>
      ${eta}
      ${btn(args.trackingUrl, "Track your order")}
    `);

    await resend.sendEmail(ctx, {
      from: FROM,
      to: args.to,
      subject: `Your order ${args.orderNumber} has shipped`,
      html,
    });
  },
});

// ─── Delivery confirmation ────────────────────────────────────────────────────

export const sendDeliveryConfirmation = internalMutation({
  args: {
    to: v.string(),
    firstName: v.string(),
    orderNumber: v.string(),
  },
  handler: async (ctx, args) => {
    const html = base(`
      <h2 style="color:#236f6b;margin-top:0">Your order has been delivered!</h2>
      <p>Hi ${args.firstName}, your order <strong>${args.orderNumber}</strong> has been delivered.</p>
      <p>We hope your pets love their new goodies! If anything is wrong with your order, please contact our support team.</p>
    `);

    await resend.sendEmail(ctx, {
      from: FROM,
      to: args.to,
      subject: `Your order ${args.orderNumber} has been delivered`,
      html,
    });
  },
});

// ─── Cancellation ─────────────────────────────────────────────────────────────

export const sendCancellationNotice = internalMutation({
  args: {
    to: v.string(),
    firstName: v.string(),
    orderNumber: v.string(),
  },
  handler: async (ctx, args) => {
    const html = base(`
      <h2 style="color:#f2705a;margin-top:0">Order cancelled</h2>
      <p>Hi ${args.firstName}, your order <strong>${args.orderNumber}</strong> has been cancelled.</p>
      <p>If you did not request this cancellation or need help, please get in touch with our support team.</p>
    `);

    await resend.sendEmail(ctx, {
      from: FROM,
      to: args.to,
      subject: `Your order ${args.orderNumber} has been cancelled`,
      html,
    });
  },
});

// ─── Refund ───────────────────────────────────────────────────────────────────

export const sendRefundNotice = internalMutation({
  args: {
    to: v.string(),
    firstName: v.string(),
    orderNumber: v.string(),
    total: v.number(),
    currency: v.string(),
  },
  handler: async (ctx, args) => {
    const html = base(`
      <h2 style="color:#236f6b;margin-top:0">Refund processed</h2>
      <p>Hi ${args.firstName}, your refund for order <strong>${args.orderNumber}</strong> has been processed.</p>
      <p><strong>Refund amount:</strong> ${formatPrice(args.total, args.currency)}</p>
      <p>Please allow 5–10 business days for the amount to appear on your statement.</p>
    `);

    await resend.sendEmail(ctx, {
      from: FROM,
      to: args.to,
      subject: `Refund processed for order ${args.orderNumber}`,
      html,
    });
  },
});

// ─── Return label ─────────────────────────────────────────────────────────────

export const sendReturnLabelEmail = internalMutation({
  args: {
    to: v.string(),
    firstName: v.string(),
    orderNumber: v.string(),
    returnLabelUrl: v.string(),
  },
  handler: async (ctx, args) => {
    const html = base(`
      <h2 style="color:#236f6b;margin-top:0">Your return label is ready</h2>
      <p>Hi ${args.firstName}, your return request for order <strong>${args.orderNumber}</strong> has been accepted.</p>
      <p>Please use the link below to download your prepaid return label and attach it to your parcel.</p>
      ${btn(args.returnLabelUrl, "Download return label")}
      <p style="margin-top:16px;font-size:13px;color:#888">Once we receive your return, we&rsquo;ll process your refund promptly.</p>
    `);

    await resend.sendEmail(ctx, {
      from: FROM,
      to: args.to,
      subject: `Return label for order ${args.orderNumber}`,
      html,
    });
  },
});

// ─── Return requested ─────────────────────────────────────────────────────────

export const sendReturnRequestedNotice = internalMutation({
  args: {
    to: v.string(),
    firstName: v.string(),
    orderNumber: v.string(),
  },
  handler: async (ctx, args) => {
    const html = base(`
      <h2 style="color:#236f6b;margin-top:0">Return request received</h2>
      <p>Hi ${args.firstName}, we&rsquo;ve received your return request for order <strong>${args.orderNumber}</strong>.</p>
      <p>Our team will review it and get back to you within 2 business days.</p>
    `);

    await resend.sendEmail(ctx, {
      from: FROM,
      to: args.to,
      subject: `Return request received for order ${args.orderNumber}`,
      html,
    });
  },
});