<?php
// FILE: 02_supportFuncs.php
// Description: Support and utility functions


function getPasswordList(string $passwordFile, string $key): array {
    if (!file_exists($passwordFile)) return [];
    $raw = file_get_contents($passwordFile);

    // Plain text mode
    if ($key === "") return json_decode($raw, true) ?: [];

    // Encrypted mode
    $json = decryptData($raw, $key);
    return $json === false ? [] : (json_decode($json, true) ?: []);
}

function savePasswordList(string $passwordFile, array $data, string $key): void {
    $json = json_encode($data, JSON_PRETTY_PRINT);
    $out  = $key === "" ? $json : encryptData($json, $key);
    file_put_contents($passwordFile, $out);
}

/* Encryption helpers – unchanged except key now fixed */
function encryptData(string $plain, string $key): string {
    $m  = "aes-256-cbc";
    $iv = openssl_random_pseudo_bytes(openssl_cipher_iv_length($m));
    $enc= openssl_encrypt($plain, $m, $key, 0, $iv);
    return base64_encode($iv . $enc);
}

function decryptData(string $cipherB64, string $key): string|false {
    $m  = "aes-256-cbc";
    $bin= base64_decode($cipherB64, true);
    if ($bin === false) return false;
    $ivLen = openssl_cipher_iv_length($m);
    $iv  = substr($bin, 0, $ivLen);
    $enc = substr($bin, $ivLen);
    return openssl_decrypt($enc, $m, $key, 0, $iv);
}

function generatePassword(int $len = 14): string {
    $chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()_-=+';
    return substr(str_shuffle(str_repeat($chars, (int)ceil($len / strlen($chars)))), 0, $len);
}


/**
 * Return the current 6-digit TOTP for a given base32 secret.
 * On error (empty or invalid secret) returns ''.
 */
function currentOtpCode(string $secret): string
{
    if ($secret === '') return '';
    try {
        $totp = OTPHP\TOTP::create($secret);
        return $totp->now();        // 6-digit string
    } catch (\Throwable $e) {
        return '';
    }
}
?>