<?php

namespace Studip\LTI13a;

use OAT\Library\Lti1p3Core\Security\Nonce\NonceGeneratorInterface;
use OAT\Library\Lti1p3Core\Security\Nonce\NonceInterface;
use OAT\Library\Lti1p3Core\Security\Nonce\Nonce;

class NonceGenerator implements NonceGeneratorInterface
{
    public function __construct(
        protected bool $pass_nonce_from_request = false
    ) {
    }

    #[\Override]
    public function generate(?int $ttl = null): NonceInterface
    {
        $expiration = new \DateTime();
        $expiration = $expiration->add(new \DateInterval('PT5M'));
        if ($this->pass_nonce_from_request) {
            return new Nonce(
                \Request::get('nonce'),
                $expiration
            );
        } else {
            $nonce = md5(random_bytes(16) . 'lti13a_nonce');
            return new Nonce(
                $nonce,
                $expiration
            );
        }
    }
}