import { XWing } from "@noble/post-quantum/hybrid.js";
import { xchacha20poly1305 } from "@noble/ciphers/chacha.js";
import { randomBytes } from "@noble/hashes/utils.js";
import { sha3_512 } from "@noble/hashes/sha3.js";
import type { EncryptedPayload } from "./types.ts";

export function encryptText(
  publicKey: Uint8Array,
  text: string,
): EncryptedPayload {
  // Create a copy of the public key to prevent mutation by XWing.encapsulate
  const publicKeyCopy = new Uint8Array(publicKey);
  const { cipherText, sharedSecret } = XWing.encapsulate(publicKeyCopy);
  const nonce = randomBytes(24);
  const contentBytes = new TextEncoder().encode(text);
  const cipher = xchacha20poly1305(sharedSecret, nonce);
  const content = cipher.encrypt(contentBytes);
  const hash = sha3_512(contentBytes);

  return {
    cipherText: cipherText.toBase64(),
    content: content.toBase64(),
    nonce: nonce.toBase64(),
    hash: hash.toBase64(),
    length: contentBytes.byteLength,
  };
}