<?php
declare(strict_types=1);

$localConfig = __DIR__ . '/config.local.php';
$config = is_readable($localConfig) ? require $localConfig : [];

$dbConfig = [
    'host' => $config['db_host'] ?? getenv('PHPSITE_DB_HOST') ?: '127.0.0.1',
    'name' => $config['db_name'] ?? getenv('PHPSITE_DB_NAME') ?: 'phpsite',
    'user' => $config['db_user'] ?? getenv('PHPSITE_DB_USER') ?: 'phpsite_app',
    'pass' => $config['db_pass'] ?? getenv('PHPSITE_DB_PASS') ?: '',
];

// Include NetBox integration
require_once __DIR__ . '/netbox_integration/config.php';

function db(): PDO
{
    static $pdo = null;
    global $dbConfig;

    if ($pdo instanceof PDO) {
        return $pdo;
    }

    $dsn = sprintf(
        'mysql:host=%s;dbname=%s;charset=utf8mb4',
        $dbConfig['host'],
        $dbConfig['name']
    );

    $pdo = new PDO($dsn, $dbConfig['user'], $dbConfig['pass'], [
        PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
        PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
        PDO::ATTR_EMULATE_PREPARES => false,
    ]);

    return $pdo;
}

function start_app_session(): void
{
    if (session_status() === PHP_SESSION_ACTIVE) {
        return;
    }

    session_set_cookie_params([
        'lifetime' => 0,
        'path' => '/',
        'httponly' => true,
        'samesite' => 'Lax',
    ]);
    session_start();
}

function h(?string $value): string
{
    return htmlspecialchars($value ?? '', ENT_QUOTES | ENT_SUBSTITUTE, 'UTF-8');
}

function require_login(): void
{
    start_app_session();

    if (empty($_SESSION['loggedin']) || $_SESSION['loggedin'] !== true) {
        header('Location: /login.php');
        exit;
    }
}

function csrf_token(): string
{
    start_app_session();

    if (empty($_SESSION['csrf_token'])) {
        $_SESSION['csrf_token'] = bin2hex(random_bytes(32));
    }

    return $_SESSION['csrf_token'];
}

function verify_csrf(?string $token): bool
{
    start_app_session();

    return is_string($token)
        && isset($_SESSION['csrf_token'])
        && hash_equals($_SESSION['csrf_token'], $token);
}