import { hexFromBytes, utf8Bytes } from "@/worker/auth/bytes";

async function importHkdfMaterial(secret: string): Promise<CryptoKey> {
  return await crypto.subtle.importKey("raw", utf8Bytes(secret), "HKDF", false, ["deriveBits", "deriveKey"]);
}

export async function deriveHmacKeyBytes(secret: string, salt: string, info: string): Promise<Uint8Array> {
  const material = await importHkdfMaterial(secret);
  const bits = await crypto.subtle.deriveBits(
    {
      name: "HKDF",
      hash: "SHA-256",
      salt: utf8Bytes(salt),
      info: utf8Bytes(info),
    },
    material,
    256,
  );
  return new Uint8Array(bits);
}

export async function sha256Hex(value: string): Promise<string> {
  const digest = await crypto.subtle.digest("SHA-256", utf8Bytes(value));
  return hexFromBytes(new Uint8Array(digest));
}