function pleiofile_add_folder_to_zip(ZipArchive &$zip_archive, ElggObject $folder, $folder_path = "")
{
if (!empty($zip_archive) && !empty($folder) && elgg_instanceof($folder, "object", "folder")) {
$folder_title = elgg_get_friendly_title($folder->title);
$zip_archive->addEmptyDir($folder_path . $folder_title);
$folder_path .= $folder_title . DIRECTORY_SEPARATOR;
$file_options = array("type" => "object", "subtype" => "file", "limit" => false, "relationship" => "folder_of", "relationship_guid" => $folder->getGUID());
// add files from this folder to the zip
if ($files = elgg_get_entities_from_relationship($file_options)) {
foreach ($files as $file) {
// check if the file exists
if ($zip_archive->statName($folder_path . $file->originalfilename) === false) {
// doesn't exist, so add
$zip_archive->addFile($file->getFilenameOnFilestore(), $folder_path . sanitize_file_name($file->originalfilename));
} else {
// file name exists, so create a new one
$ext_pos = strrpos($file->originalfilename, ".");
$file_name = substr($file->originalfilename, 0, $ext_pos) . "_" . $file->getGUID() . substr($file->originalfilename, $ext_pos);
$zip_archive->addFile($file->getFilenameOnFilestore(), $folder_path . sanitize_file_name($file_name));
}
}
}
// check if there are subfolders
$folder_options = array("type" => "object", "subtype" => "folder", "limit" => false, "metadata_name_value_pairs" => array("parent_guid" => $folder->getGUID()));
if ($sub_folders = elgg_get_entities_from_metadata($folder_options)) {
foreach ($sub_folders as $sub_folder) {
pleiofile_add_folder_to_zip($zip_archive, $sub_folder, $folder_path);
}
}
}
}
// doesn't exist, so add
$zip->addFile($file->getFilenameOnFilestore(), $file->originalfilename);
} else {
// file name exists, so create a new one
$ext_pos = strrpos($file->originalfilename, ".");
$file_name = substr($file->originalfilename, 0, $ext_pos) . "_" . $file->getGUID() . substr($file->originalfilename, $ext_pos);
$zip->addFile($file->getFilenameOnFilestore(), $file_name);
}
}
}
}
// add folder (and their content) to the zip
if (!empty($folder_guids)) {
foreach ($folder_guids as $folder_guid) {
if ($folder = get_entity($folder_guid)) {
pleiofile_add_folder_to_zip($zip, $folder);
}
}
}
// done adding content, so save the zip
$zip->close();
if (file_exists($zip_filename)) {
// output the correct headers
header('Pragma: public');
header('Content-type: application/zip');
header('Content-Disposition: attachment; filename="folder_contents.zip"');
header('Content-Length: ' . filesize($zip_filename));
ob_clean();
flush();
readfile($zip_filename);
unlink($zip_filename);