seeky/index.php

<?php
declare(strict_types=1);

// -------------------- CONSTANTES --------------------
const CACHE_DIR       = '/var/cache/homepage';
const INSTANCES_JSON  = CACHE_DIR . '/instances.json';
const URLS_TXT        = CACHE_DIR . '/urls.txt';
const INSTANCES_URL   = 'https://searx.space/data/instances.json';
const CACHE_MAX_AGE   = 3600; // 1 heure
const BANG_FILE       = __DIR__ . '/bang.json';

// -------------------- HEADERS DE SÉCURITÉ --------------------
header('X-Frame-Options: SAMEORIGIN');
header('X-Content-Type-Options: nosniff');
header('Referrer-Policy: no-referrer-when-downgrade');
header("Content-Security-Policy: default-src 'none'; frame-ancestors 'none'; sandbox");

// -------------------- CLASSES --------------------
class CacheManager
{
    private array $urlsCache = [];

    public function __construct(private string $cacheDir = CACHE_DIR) {
        if (!is_dir($cacheDir) && !mkdir($cacheDir, 0755, true)) {
            throw new RuntimeException("Impossible de créer le dossier cache");
        }
    }

    public function isExpired(): bool {
        return !file_exists(URLS_TXT) || (time() - filemtime(URLS_TXT)) > CACHE_MAX_AGE;
    }

    public function downloadInstances(): bool {
        $data = file_get_contents(INSTANCES_URL);
        if ($data === false) return false;
        return $this->safeWrite(INSTANCES_JSON, $data);
    }

    public function extractValidUrls(): bool {
        if (!file_exists(INSTANCES_JSON)) return false;

        $json = json_decode(file_get_contents(INSTANCES_JSON), true);
        if (!isset($json['instances']) || !is_array($json['instances'])) return false;

        $valid = array_filter(array_keys($json['instances']), function($url) use ($json) {
            $data = $json['instances'][$url] ?? [];
            return ($data['network_type'] ?? '') === 'normal'
                && ($data['http']['status_code'] ?? 0) === 200
                && ($data['timing']['search']['success_percentage'] ?? 0) === 100.0
                && ($data['timing']['initial']['success_percentage'] ?? 0) === 100.0
                && filter_var($url, FILTER_VALIDATE_URL)
                && in_array(parse_url($url, PHP_URL_SCHEME), ['http','https'], true);
        });

        if (empty($valid)) return false;

        return $this->safeWrite(URLS_TXT, implode("\n", array_map('rtrim', $valid)));
    }

    private function safeWrite(string $file, string $data): bool {
        $written = file_put_contents($file, $data, LOCK_EX);
        return $written !== false && $written === strlen($data);
    }

    public function loadUrls(): array {
        if (empty($this->urlsCache)) {
            if (!file_exists(URLS_TXT)) return [];
            $urls = file(URLS_TXT, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
            $this->urlsCache = array_filter($urls, fn($url) => filter_var($url, FILTER_VALIDATE_URL));
        }
        return $this->urlsCache;
    }

    public function getRandomUrl(): string {
        $urls = $this->loadUrls();
        if (empty($urls)) throw new RuntimeException("Aucune URL disponible");
        return $urls[array_rand($urls)];
    }
}

class BangManager
{
    private array $bangs = [];

    public function __construct(private string $file = BANG_FILE) {
        $this->loadBangs();
    }

    private function loadBangs(): void {
        if (!file_exists($this->file)) return;
        $data = json_decode(file_get_contents($this->file), true);
        $this->bangs = is_array($data) ? $data : [];
    }

    public function tryRedirect(string $query): bool {
        if (!str_starts_with($query, '!')) return false;
        if (!preg_match('/^!(\w+)\s?(.*)$/u', $query, $matches)) return false;

        [$bangCode, $searchTerm] = [$matches[1], trim($matches[2])];
        if ($searchTerm === '') return false;

        foreach ($this->bangs as $bang) {
            if (($bang['bang'] ?? '') === $bangCode) {
                header("Location: " . rtrim($bang['url'], '/') . '?q=' . rawurlencode($searchTerm));
                exit;
            }
        }
        return false;
    }
}

class RequestHandler
{
    public function __construct(private CacheManager $cache, private BangManager $bang) {}

    public function handle(): void {
        $method = $_SERVER['REQUEST_METHOD'] ?? 'GET';
        $query = $_REQUEST['q'] ?? null;

        if ($query !== null && !$this->bang->tryRedirect($query)) {
            $instance = rtrim($this->cache->getRandomUrl(), '/');

            if ($method === 'GET') {
                $this->redirectGet($instance, $query);
            } elseif ($method === 'POST') {
                $this->proxyPost($instance, $_POST);
            } else {
                http_response_code(405);
                exit('Méthode non autorisée');
            }
        } elseif ($query === null) {
            $instance = rtrim($this->cache->getRandomUrl(), '/');
            if ($method === 'GET') {
                header("Location: $instance");
                exit;
            } elseif ($method === 'POST') {
                $this->proxyPost($instance, $_POST);
            } else {
                http_response_code(405);
                exit('Méthode non autorisée');
            }
        }
    }

    private function redirectGet(string $instance, string $query): void {
        $url = $instance . '/search?' . http_build_query(['q' => $query]);
        header("Location: $url");
        exit;
    }

    private function proxyPost(string $urlBase, array $postData): void {
        $url = $urlBase . '/search';
        $ch = curl_init($url);
        curl_setopt_array($ch, [
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_POST           => true,
            CURLOPT_POSTFIELDS     => http_build_query($postData),
            CURLOPT_HEADER         => false,
            CURLOPT_FOLLOWLOCATION => true,
            CURLOPT_TIMEOUT        => 10,
            CURLOPT_SSL_VERIFYPEER => true,
        ]);
        $response = curl_exec($ch);
        $code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        curl_close($ch);

        http_response_code($code);
        echo $response;
        exit;
    }
}

// -------------------- EXECUTION --------------------
try {
    $cache = new CacheManager();
    if ($cache->isExpired()) {
        if (!$cache->downloadInstances() || !$cache->extractValidUrls()) {
            http_response_code(500);
            exit('Erreur interne : impossible de générer le cache.');
        }
    }

    $bang = new BangManager();
    $handler = new RequestHandler($cache, $bang);
    $handler->handle();

} catch (\Throwable $e) {
    http_response_code(500);
    exit('Erreur interne : ' . $e->getMessage());
}