<?php
include 'protect.php';
include 'db.php';
require_once __DIR__ . '/database_backup_helpers.php';

try {
    $backup = buildAppDatabaseBackup($conn);
    $content = (string) ($backup['content'] ?? '');
    $filename = (string) ($backup['filename'] ?? 'housetab_store_backup.sql');

    if (function_exists('gzencode')) {
        $gzContent = gzencode($content, 9);
        if ($gzContent === false) {
            throw new RuntimeException('Could not compress the backup file.');
        }

        header('Content-Type: application/gzip');
        header('Content-Disposition: attachment; filename="' . $filename . '.gz"');
        header('Content-Length: ' . strlen($gzContent));
        header('Cache-Control: no-store, no-cache, must-revalidate');
        header('Pragma: no-cache');
        header('Expires: 0');
        echo $gzContent;
        exit;
    }

    header('Content-Type: application/sql');
    header('Content-Disposition: attachment; filename="' . $filename . '"');
    header('Content-Length: ' . strlen($content));
    header('Cache-Control: no-store, no-cache, must-revalidate');
    header('Pragma: no-cache');
    header('Expires: 0');
    echo $content;
    exit;
} catch (Throwable $e) {
    http_response_code(500);
    echo htmlspecialchars($e->getMessage(), ENT_QUOTES, 'UTF-8');
    exit;
}