// utils/crypto.ts
export const generateUserKeyPair = async () => {
  return await window.crypto.subtle.generateKey(
    {
      name: "RSASSA-PKCS1-v1_5",
      modulusLength: 2048,
      publicExponent: new Uint8Array([1, 0, 1]), // 65537
      hash: "SHA-256",
    },
    true, // extractable
    ["sign", "verify"]
  );
};

export const signVote = async (data: any, privateKey: CryptoKey) => {
  const encoder = new TextEncoder();
  const encodedData = encoder.encode(JSON.stringify(data));

  const signature = await window.crypto.subtle.sign(
    "RSASSA-PKCS1-v1_5",
    privateKey,
    encodedData
  );

  // Convert to Base64 or Hex to store in Yjs easily
  return btoa(String.fromCharCode(...new Uint8Array(signature)));
};

export const verifyVote = async (data: any, signatureStr: string, publicKey: CryptoKey) => {
  const encoder = new TextEncoder();
  const encodedData = encoder.encode(JSON.stringify(data));
  
  // Convert Base64 back to Uint8Array
  const signature = Uint8Array.from(atob(signatureStr), c => c.charCodeAt(0));

  return await window.crypto.subtle.verify(
    "RSASSA-PKCS1-v1_5",
    publicKey,
    signature,
    encodedData
  );
};