<?php

function encryptText(string $text, string $key): array
{
    $iv     = random_bytes(16);
    $cipher = openssl_encrypt($text, 'AES-256-CBC', $key, 0, $iv);
    if ($cipher === false) {
        throw new RuntimeException('Encryption failed.');
    }
    return [
        'cipher' => $cipher,
        'iv'     => base64_encode($iv),
    ];
}

function decryptText(string $cipher, string $iv, string $key): string|false
{
    return openssl_decrypt($cipher, 'AES-256-CBC', $key, 0, base64_decode($iv));
}

function generateId(): string
{
    return bin2hex(random_bytes(16));
}

function jsonResponse(array $data, int $status = 200): void
{
    http_response_code($status);
    header('Content-Type: application/json');
    echo json_encode($data);
    exit;
}