<?php
require_once 'includes/db.php';

$id = $_GET['id'] ?? null;

try {
    $app = null;

    if ($id) {
        // 按 ID 下载指定版本
        $stmt = $db->prepare("SELECT * FROM apps WHERE id = ?");
        $stmt->execute([$id]);
        $app = $stmt->fetch(PDO::FETCH_ASSOC);
    } else {
        // 兼容旧版：返回最新版本
        $stmt = $db->query("SELECT * FROM apps ORDER BY upload_time DESC LIMIT 1");
        $app = $stmt->fetch(PDO::FETCH_ASSOC);
    }

    if ($app && file_exists('data/apps/' . $app['filename'])) {
        $file_path = 'data/apps/' . $app['filename'];
        $file_size = filesize($file_path);

        // 设置下载响应头
        header('Content-Type: application/vnd.android.package-archive');
        header('Content-Disposition: attachment; filename="' . $app['original_name'] . '"');
        header('Content-Length: ' . $file_size);
        header('Cache-Control: must-revalidate');
        header('Pragma: public');

        // 清空输出缓冲
        if (ob_get_level()) {
            ob_end_clean();
        }

        // 输出文件
        readfile($file_path);
        exit;
    } else {
        header('Content-Type: text/html; charset=utf-8');
        die('错误：APK 文件不存在');
    }
} catch (Exception $e) {
    header('Content-Type: text/html; charset=utf-8');
    die('错误：' . htmlspecialchars($e->getMessage()));
}