/**
 * Generate HMAC-SHA256 signature for webhook payload
 */
export async function generateWebhookSignature(
  secret: string,
  payload: string,
): Promise<string> {
  const encoder = new TextEncoder();
  const keyData = encoder.encode(secret);
  const messageData = encoder.encode(payload);

  const cryptoKey = await crypto.subtle.importKey(
    "raw",
    keyData,
    { name: "HMAC", hash: "SHA-256" },
    false,
    ["sign"],
  );

  const signature = await crypto.subtle.sign("HMAC", cryptoKey, messageData);
  const hashArray = Array.from(new Uint8Array(signature));
  return hashArray.map((b) => b.toString(16).padStart(2, "0")).join("");
}