<?php
/**
 * @copyright Copyright (c) 2016 Lukas Reschke <lukas@statuscode.ch>
 *
 * @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\Richdocuments\WOPI;

use OCP\AppFramework\Utility\ITimeFactory;
use OCP\Files\IAppData;
use OCP\Files\NotFoundException;
use OCP\Files\SimpleFS\ISimpleFolder;
use OCP\Http\Client\IClientService;
use OCP\IConfig;
use OCP\IL10N;
use OCP\Notification\IApp;

class DiscoveryManager {
	/** @var IClientService */
	private $clientService;
	/** @var ISimpleFolder */
	private $appData;
	/** @var IConfig */
	private $config;
	/** @var IL10N */
	private $l10n;
	/** @var ITimeFactory */
	private $timeFactory;

	/**
	 * @param IClientService $clientService
	 * @param IAppData $appData
	 * @param IConfig $config
	 * @param IL10N $l10n
	 * @param ITimeFactory $timeFactory
	 */
	public function __construct(IClientService $clientService,
								IAppData $appData,
								IConfig $config,
								IL10N $l10n,
								ITimeFactory $timeFactory) {
		$this->clientService = $clientService;
		try {
			$this->appData = $appData->getFolder('richdocuments');
		} catch (NotFoundException $e) {
			$this->appData = $appData->newFolder('richdocuments');
		}
		$this->config = $config;
		$this->l10n = $l10n;
		$this->timeFactory = $timeFactory;
	}

	public function get() {
		// First check if there is a local valid discovery file
		try {
			$file = $this->appData->getFile('discovery.xml');
			$decodedFile = json_decode($file->getContent(), true);
			if($decodedFile['timestamp'] + 3600 > $this->timeFactory->getTime()) {
				return $decodedFile['data'];
			}
		} catch (NotFoundException $e) {
			$file = $this->appData->newFile('discovery.xml');
		}

		$remoteHost = $this->config->getAppValue('richdocuments', 'wopi_url');
		$wopiDiscovery = $remoteHost . '/hosting/discovery';

		$client = $this->clientService->newClient();
		try {
			$response = $client->get($wopiDiscovery);
		} catch (\Exception $e) {
			$error_message = $e->getMessage();
			if (preg_match('/^cURL error ([0-9]*):/', $error_message, $matches)) {
				$admin_check = $this->l10n->t('Please ask your administrator to check the Collabora Online server setting. The exact error message was: ') . $error_message;

				$curl_error = $matches[1];
				switch ($curl_error) {
					case '1':
						throw new ResponseException($this->l10n->t('Collabora Online: The protocol specified in "%s" is not allowed.', array($wopiRemote)), $admin_check);
					case '3':
						throw new ResponseException($this->l10n->t('Collabora Online: Malformed URL "%s".', array($wopiRemote)), $admin_check);
					case '6':
						throw new ResponseException($this->l10n->t('Collabora Online: Cannot resolve the host "%s".', array($wopiRemote)), $admin_check);
					case '7':
						throw new ResponseException($this->l10n->t('Collabora Online: Cannot connect to the host "%s".', array($wopiRemote)), $admin_check);
					case '60':
						throw new ResponseException($this->l10n->t('Collabora Online: SSL certificate is not installed.'), $this->l10n->t('Please ask your administrator to add ca-chain.cert.pem to the ca-bundle.crt, for example "cat /etc/loolwsd/ca-chain.cert.pem >> <server-installation>/resources/config/ca-bundle.crt" . The exact error message was: ') . $error_message);
				}
			}
			throw new ResponseException($this->l10n->t('Collabora Online unknown error: ') . $error_message, $contact_admin);
		}

		$responseBody = $response->getBody();
		$file->putContent(
			json_encode([
				'data' => $responseBody,
				'timestamp' => $this->timeFactory->getTime(),
			])
		);
		return $responseBody;
	}
}