Elgg-Lorea-Hydra/mod/file_tools/pages/file/download.php

<?php

$zip_dir = elgg_get_config("dataroot") . 'file_tools/zip_temp/';

if (!file_exists($zip_dir)) {
	mkdir($zip_dir, 0755, true);
}

$zip_filename = tempnam($zip_dir, "download_");

$file_guids = get_input("file_guids");
$folder_guids = get_input("folder_guids");

if (empty($file_guids) && empty($folder_guids)) {
	register_error(elgg_echo("InvalidParameterException:MissingParameter"));
	forward(REFERER);
}

$zip = new ZipArchive();

if ($zip->open($zip_filename, ZIPARCHIVE::CREATE) !== true) {
	register_error(elgg_echo("file:downloadfailed"));
	forward(REFERER);
}

// add files to the zip
if (!empty($file_guids)) {
	foreach ($file_guids as $file_guid) {
		if ($file = get_entity($file_guid)) {
			// check if the name exists in the zip
			if ($zip->statName($file->originalfilename) === false) {
				// 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($folder_guid)) {
			file_tools_add_folder_to_zip($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);
} else {
	register_error(elgg_echo("file:downloadfailed"));
	forward(REFERER);
}