import {
    encodeBitString,
    encodeNull,
    encodeObjectIdentifier,
    encodeSequence,
} from "../asn1/writer.js";
import type { RsaPublicKey } from "./keys.types.js";
import { OID_RSA_ENCRYPTION } from "./oid.js";
import { serializeRsaPublicKeyPkcs1 } from "./serialize-pkcs1-public.js";

/**
 * Serialise an `RsaPublicKey` to a DER-encoded `SubjectPublicKeyInfo`
 * (RFC 5280 §4.1) wrapping a PKCS#1 `RSAPublicKey`.
 */
export function serializeRsaPublicKeySpki(key: RsaPublicKey): Uint8Array {
    const algorithm = encodeSequence(
        encodeObjectIdentifier(OID_RSA_ENCRYPTION),
        encodeNull()
    );
    const subjectPublicKey = encodeBitString(serializeRsaPublicKeyPkcs1(key));
    return encodeSequence(algorithm, subjectPublicKey);
}