a.php

<?php

require __DIR__ . '/bootstrap.php';

date_default_timezone_set('UTC');

ini_set('max_execution_time', 600);
ini_set('display_errors', 1);
error_reporting(1);

set_time_limit(600);

$root = dirname(__FILE__);

@include $root . '/storage/configuration/user_setup.php';
require_once $root . '/app/koken/Shutter/Shutter.php';
require_once $root . '/app/koken/Utils/KokenAPI.php';
require $root . '/app/application/libraries/phpzip/autoload.php';

if (!defined('LOOPBACK_HOST_HEADER')) {
    define('LOOPBACK_HOST_HEADER', false);
}

Shutter::enable();
Shutter::hook('image.boot');

if (isset($_GET['path'])) {
    $path = $_GET['path'];
} else if (isset($_SERVER['QUERY_STRING'])) {
    $path = urldecode($_SERVER['QUERY_STRING']);
} else if (isset($_SERVER['PATH_INFO'])) {
    $path = $_SERVER['PATH_INFO'];
} else if (isset($_SERVER['REQUEST_URI'])) {
    $path = preg_replace('/.*\/a.php/', '', $_SERVER['REQUEST_URI']);
}

$ds = DIRECTORY_SEPARATOR;

// File exists, but rewites not supported
if (file_exists($root . '/storage/cache/albums' . $path)) {
    $file = $root . '/storage/cache/albums' . $path;

    header('Content-Description: File Transfer');
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename="' . basename($file) . '"');
    header('Expires: 0');
    header('Cache-Control: must-revalidate');
    header('Pragma: public');
    header('Content-Length: ' . filesize($file));

    $disabled_functions = explode(',', ini_get('disable_functions'));

    if (is_callable('readfile') && !in_array('readfile', $disabled_functions)) {
        readfile($file);
        exit;
    } else {
        die(file_get_contents($file));
    }
}

preg_match('/^\/([0-9]{3}\/[0-9]{3})\/[0-9]+\/.+$/i', $path, $matches);

if (empty($matches)) {
    // Bad request
    header('HTTP/1.1 403 Forbidden');
    exit;
}

$id = (int)str_replace('/', '', $matches[1]);

$KokenAPI = new KokenAPI;
$result = $KokenAPI->get('/albums/' . $id . '/content/limit:500');

if (!isset($result['album']) || $result['album']['album_type'] === 'set') {
    header('HTTP/1.1 403 Forbidden');
    exit;
}

$visibility_values = array('public', 'unlisted', 'private');
$album_visibility = array_search($result['album']['visibility']['raw'], $visibility_values);

$ts = $result['album']['modified_on']['timestamp'];
$album_cache_key = 'albums/' . $matches[1];
$cache_key = $album_cache_key . '/' . $ts . '/' . basename($path);

Shutter::clear_cache($album_cache_key);

$zip = new \PHPZip\Zip\File\Zip();

// Create an empty file
Shutter::write_cache($cache_key, '');
$zip->setZipFile($root . '/storage/cache/' . $cache_key);

foreach ($result['content'] as $content) {
    $md = $content['max_download']['raw'];
    $visibility = array_search($content['visibility']['raw'], $visibility_values);

    if ($md !== 'none' && $visibility <= $album_visibility) {
        if ($md === 'original') {
            $url = $root . $content['original']['relative_url'];
        } else {
            $url = $content['presets'][$md]['url'];
            $relative_url = preg_replace('/.+?(?=\/storage\/cache\/images\/)/', $root, $url);

            if (file_exists($relative_url)) {
                $url = $relative_url;
            }
        }

        $file = false;
        for ($i = 1; $i <= 10; $i++) {
            $file = file_get_contents($url);

            if ($file) {
                break;
            } else {
                sleep(1);
            }
        }

        if ($file) {
            $zip->addFile($file, $content['filename']);
        }
    }
}

if ($zip->getArchiveSize() !== 0) {
    $zip->sendZip(basename($path));
} else {
    Shutter::clear_cache($album_cache_key);
}