<?php

// 0) Umgebung / Domains / Error-Level
require_once __DIR__ . "/config.php";

// -----------------------------------------------------------
// Session starten
// -----------------------------------------------------------
if (php_sapi_name() !== 'cli') {
    if (session_status() === PHP_SESSION_NONE) {

        session_name('usbcheck_session');

        session_set_cookie_params([
            'lifetime' => 0,
            'path'     => '/',
            'domain'   => '',
            'secure'   => (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off'),
            'httponly' => true,
            'samesite' => 'Lax',
        ]);

        session_start();
    }
}

// -----------------------------------------------------------
// Helper: Browser-Sprache aus HTTP_ACCEPT_LANGUAGE
// -----------------------------------------------------------
function usb_detect_browser_lang(array $availableLangs): ?string
{
    if (empty($_SERVER['HTTP_ACCEPT_LANGUAGE']) || empty($availableLangs)) {
        return null;
    }

    $raw   = $_SERVER['HTTP_ACCEPT_LANGUAGE'];
    $parts = explode(',', $raw);

    foreach ($parts as $part) {
        $part = trim($part);
        if ($part === '') continue;

        // z.B. "de-DE;q=0.9" → "de-DE"
        $langPart = explode(';', $part)[0];
        $code2    = strtolower(substr($langPart, 0, 2));

        if (preg_match('/^[a-z]{2}$/', $code2) && isset($availableLangs[$code2])) {
            return $code2;
        }
    }

    return null;
}

// -----------------------------------------------------------
// 1) Sprache aus ?lang holen (nur 2-Buchstaben-Code validieren)
// -----------------------------------------------------------
$requestedLang = null;

if (isset($_GET['lang']) && is_string($_GET['lang'])) {
    $tmp = strtolower($_GET['lang']);
    if (preg_match('/^[a-z]{2}$/', $tmp)) {
        $requestedLang = $tmp;
    }
}

// -----------------------------------------------------------
// 2) Verfügbare JSON-Sprachen aus /public/assets/i18n
// -----------------------------------------------------------
$i18nDir = __DIR__ . '/../public/assets/i18n';

$langFiles = [];
if (is_dir($i18nDir)) {
    $langFiles = glob($i18nDir . '/*.json') ?: [];
}

$availableLangs = [];

// Alle vorhandenen JSONs einsammeln
foreach ($langFiles as $file) {
    $raw = @file_get_contents($file);
    if ($raw === false) {
        error_log('i18n: Konnte Datei nicht lesen: ' . $file);
        continue;
    }

    $json = json_decode($raw, true);
    if (!is_array($json)) {
        error_log('i18n: Ungültiges JSON in ' . $file . ' :: ' . json_last_error_msg());
        continue;
    }

    $meta = $json['meta'] ?? [];

    // optional: meta.enabled === false → ausblenden (z.B. Templates)
    if (array_key_exists('enabled', $meta) && $meta['enabled'] === false) {
        continue;
    }

    // Sprachcode aus meta.code oder Dateiname
    $code = strtolower($meta['code'] ?? basename($file, '.json'));

    // Nur 2-Buchstaben-Codes zulassen (de, en, fr, it, dk, es, ...)
    if (!preg_match('/^[a-z]{2}$/', $code)) {
        continue;
    }

    $label = $meta['label'] ?? strtoupper($code);
    $flag  = $meta['flag']  ?? '🏳️';   // Flag kommt primär aus JSON, sonst neutrale Flagge

    $availableLangs[$code] = [
        'code'  => $code,
        'label' => $label,
        'flag'  => $flag,
    ];
}

// Falls wirklich gar keine Sprachdatei existiert → Minimal-Fallback
if (empty($availableLangs)) {
    $availableLangs = [
        'en' => [
            'code'  => 'en',
            'label' => 'English',
            'flag'  => '🏳️',
        ],
    ];
}

// -----------------------------------------------------------
// 3) Endgültige Sprache wählen nach deiner Priorität
//
//    1) ?lang=xx, wenn gültig & vorhanden
//    2) HTTP_ACCEPT_LANGUAGE (erste Sprache, 2 Buchstaben)
//    3) 'en', wenn vorhanden
//    4) sonst erste Sprache aus $availableLangs
// -----------------------------------------------------------
$lang = null;

// 1) ?lang=xx (gültig & vorhanden)
if ($requestedLang && isset($availableLangs[$requestedLang])) {
    $lang = $requestedLang;
}

// 2) Browser-Sprache aus HTTP_ACCEPT_LANGUAGE
if ($lang === null) {
    $browserLang = usb_detect_browser_lang($availableLangs);
    if ($browserLang !== null) {
        $lang = $browserLang;
    }
}

// 3) Wenn noch immer nichts → 'en', falls vorhanden
if ($lang === null && isset($availableLangs['en'])) {
    $lang = 'en';
}

// 4) Wenn immer noch nichts → erste Sprache aus $availableLangs
if ($lang === null) {
    $keys = array_keys($availableLangs);
    $lang = $keys[0] ?? 'en';
}

// -----------------------------------------------------------
// 4) Aktive Sprachdatei laden
// -----------------------------------------------------------
$activeLangFile = $i18nDir . '/' . $lang . '.json';
$activeLangData = [];

if (is_readable($activeLangFile)) {
    $json = json_decode(@file_get_contents($activeLangFile), true);
    if (is_array($json)) {
        $activeLangData = $json;
    }
}

// -----------------------------------------------------------
// 5) Fallback-Sprache (en.json), falls vorhanden
// -----------------------------------------------------------
$fallbackLangData = [];
$fallbackFile     = $i18nDir . '/en.json';

if ($lang !== 'en' && is_readable($fallbackFile)) {
    $json = json_decode(@file_get_contents($fallbackFile), true);
    if (is_array($json)) {
        $fallbackLangData = $json;
    }
}

// -----------------------------------------------------------
// 6) Globale i18n-Struktur bereitstellen
// -----------------------------------------------------------
$GLOBALS['lang']           = $lang;
$GLOBALS['availableLangs'] = $availableLangs;

$GLOBALS['i18n'] = [
    'current'  => $activeLangData,
    'fallback' => $fallbackLangData,
];

// -----------------------------------------------------------
// 7) Rest des Systems laden
// -----------------------------------------------------------
require_once __DIR__ . "/db.php";
require_once __DIR__ . '/../src/functions.php';