import * as b64u from '../util/base64url.js';
import { decodeBase64url, parseJoseHeader } from '../lib/helpers.js';
import { JWSInvalid, JWTInvalid } from '../util/errors.js';
import { validateClaimsSet, JWTClaimsBuilder, jwtData } from '../lib/jwt_claims_set.js';
import { JWS_RECOGNIZED, validateB64, validateCrit } from '../lib/options.js';
const UnsecuredJWT_base = JWTClaimsBuilder;
export class UnsecuredJWT extends UnsecuredJWT_base {
    encode() {
        const header = b64u.encode(JSON.stringify({ alg: 'none' }));
        const payload = b64u.encode(jwtData(this));
        return `${header}.${payload}.`;
    }
    static decode(jwt, options) {
        if (typeof jwt !== 'string') {
            throw new JWTInvalid('Unsecured JWT must be a string');
        }
        const { 0: encodedHeader, 1: encodedPayload, 2: signature, length } = jwt.split('.');
        if (length !== 3 || signature !== '') {
            throw new JWTInvalid('Invalid Unsecured JWT');
        }
        let header;
        let b64;
        try {
            header = parseJoseHeader(encodedHeader, JWSInvalid, 'JWS Protected Header is invalid');
            const extensions = validateCrit(JWSInvalid, JWS_RECOGNIZED, undefined, header, header);
            b64 = validateB64(header, extensions);
        }
        catch (cause) {
            if (!(cause instanceof JWSInvalid)) {
                throw cause;
            }
            throw new JWTInvalid('Invalid Unsecured JWT', { cause });
        }
        if (header.alg !== 'none') {
            throw new JWTInvalid('Invalid Unsecured JWT');
        }
        if (!b64) {
            throw new JWTInvalid('JWTs MUST NOT use unencoded payload');
        }
        const payload = validateClaimsSet(header, decodeBase64url(encodedPayload, 'payload', JWTInvalid), options);
        return { payload, header };
    }
}
