<?php

declare(strict_types=1);

/**
 * @copyright Copyright (c) 2020, Roeland Jago Douma <roeland@famdouma.nl>
 *
 * @author Roeland Jago Douma <roeland@famdouma.nl>
 *
 * @license GNU AGPL version 3 or any later version
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 *
 */
namespace OCA\DAV\Connector\Sabre;

use Sabre\DAV\ServerPlugin;
use Sabre\HTTP\Request;
use Sabre\HTTP\Response;

class PropfindCompressionPlugin extends ServerPlugin {

	/**
	 * Reference to main server object
	 *
	 * @var Server
	 */
	private $server;

	/**
	 * This initializes the plugin.
	 *
	 * This function is called by \Sabre\DAV\Server, after
	 * addPlugin is called.
	 *
	 * This method should set up the required event subscriptions.
	 *
	 * @param \Sabre\DAV\Server $server
	 * @return void
	 */
	public function initialize(\Sabre\DAV\Server $server) {
		$this->server = $server;
		$this->server->on('afterMethod:PROPFIND', [$this, 'compressResponse'], 100);
	}

	public function compressResponse(Request $request, Response $response) {
		$header = $request->getHeader('Accept-Encoding');

		if ($header === null) {
			return $response;
		}

		if (str_contains($header, 'gzip')) {
			$body = $response->getBody();
			if (is_string($body)) {
				$response->setHeader('Content-Encoding', 'gzip');
				$response->setBody(gzencode($body));
			}
		}

		return $response;
	}
}