import crypto from 'node:crypto';

function verifyTossWebhook(
  payload: string,
  signature: string,
  secret: string
): boolean {
  const expected = crypto
    .createHmac('sha256', secret)
    .update(payload)
    .digest('base64');

  return crypto.timingSafeEqual(
    Buffer.from(signature),
    Buffer.from(expected)
  );
}

// Express/Hono 핸들러에서의 사용 예시
app.post('/webhooks/tosspayments', async (req, res) => {
  const signature = req.headers['x-tosspayments-signature'] as string;
  const rawBody = await getRawBody(req);

  if (!verifyTossWebhook(rawBody.toString(), signature, process.env.TOSS_WEBHOOK_SECRET!)) {
    return res.status(401).json({ error: '유효하지 않은 서명' });
  }

  const event = JSON.parse(rawBody.toString());
  console.log(event.eventType); // 예: "PAYMENT_STATUS_CHANGED"
  res.status(200).json({ success: true });
});

import hmac
import hashlib
import base64
from flask import Flask, request, jsonify

app = Flask(__name__)

def verify_toss_webhook(payload: bytes, signature: str, secret: str) -> bool:
    expected = base64.b64encode(
        hmac.new(secret.encode(), payload, hashlib.sha256).digest()
    ).decode()
    return hmac.compare_digest(signature, expected)

@app.post("/webhooks/tosspayments")
def handle_webhook():
    signature = request.headers.get("x-tosspayments-signature", "")
    raw_body = request.get_data()

    if not verify_toss_webhook(raw_body, signature, TOSS_WEBHOOK_SECRET):
        return jsonify({"error": "유효하지 않은 서명"}), 401

    event = request.get_json()
    print(event["eventType"])  # 예: "PAYMENT_STATUS_CHANGED"
    return jsonify({"success": True})

try {
  const order = await client.carts.checkout(cart.id, {
    email: 'customer@example.com',
    shipping_address: { /* ... */ },
    payment_method: 'tosspayments',
  });
} catch (error: unknown) {
  if (error instanceof Error && 'code' in error) {
    const apiError = error as { code: string; message: string };
    switch (apiError.code) {
      case 'cart_empty':
        // 장바구니가 비어 있음
        break;
      case 'insufficient_stock':
        // 하나 이상의 상품 재고가 부족함
        break;
      case 'payment_provider_error':
        // TossPayments에서 오류 반환
        break;
      default:
        console.error(apiError.message);
    }
  }
}

try:
    order = requests.post(
        f"{base_url}/storefront/carts/{cart_id}/checkout",
        headers=headers,
        json={
            "email": "customer@example.com",
            "shipping_address": { ... },
            "payment_method": "tosspayments",
        },
    )
    order.raise_for_status()
except requests.exceptions.HTTPError as e:
    error = e.response.json()
    code = error.get("code")
    if code == "cart_empty":
        pass  # 장바구니가 비어 있음
    elif code == "insufficient_stock":
        pass  # 하나 이상의 상품 재고가 부족함
    elif code == "payment_provider_error":
        pass  # TossPayments에서 오류 반환
    else:
        print(error.get("message"))

try {
  const confirmation = await client.payments.confirm({
    payment_key: paymentKey,
    order_id: orderId,
    amount: amount,
  });
} catch (error: unknown) {
  if (error instanceof Error && 'code' in error) {
    const apiError = error as { code: string; message: string };
    switch (apiError.code) {
      case 'payment_amount_mismatch':
        // 금액이 원래 주문과 일치하지 않음
        break;
      case 'payment_already_confirmed':
        // 이미 승인된 결제
        break;
      case 'payment_expired':
        // 결제 세션이 만료됨
        break;
      case 'payment_confirm_failed':
        // TossPayments가 승인을 거부함
        break;
      default:
        console.error(apiError.message);
    }
  }
}

try:
    confirmation = requests.post(
        f"{base_url}/storefront/payments/confirm",
        headers=headers,
        json={
            "payment_key": payment_key,
            "order_id": order_id,
            "amount": amount,
        },
    )
    confirmation.raise_for_status()
except requests.exceptions.HTTPError as e:
    error = e.response.json()
    code = error.get("code")
    if code == "payment_amount_mismatch":
        pass  # 금액이 원래 주문과 일치하지 않음
    elif code == "payment_already_confirmed":
        pass  # 이미 승인된 결제
    elif code == "payment_expired":
        pass  # 결제 세션이 만료됨
    elif code == "payment_confirm_failed":
        pass  # TossPayments가 승인을 거부함
    else:
        print(error.get("message"))