<?php
/*
 * Bacula(R) - The Network Backup Solution
 * Baculum   - Bacula web interface
 *
 * Copyright (C) 2013-2015 Marcin Haba
 *
 * The main author of Baculum is Marcin Haba.
 * The original author of Bacula is Kern Sibbald, with contributions
 * from many others, a complete list can be found in the file AUTHORS.
 *
 * You may use this file and others of this release according to the
 * license defined in the LICENSE file, which includes the Affero General
 * Public License, v3.0 ("AGPLv3") and some additional permissions and
 * terms pursuant to its AGPLv3 Section 7.
 *
 * This notice must be preserved when any source code is
 * conveyed and/or propagated.
 *
 * Bacula(R) is a registered trademark of Kern Sibbald.
 */

Prado::using('Application.Class.Errors');

class API extends TModule {

	const API_VERSION = '0.1';

	protected $appCfg;

	private $allowedErrors = array(
		GenericError::ERROR_NO_ERRORS,
		BconsoleError::ERROR_INVALID_COMMAND,
		PoolError::ERROR_NO_VOLUMES_IN_POOL_TO_UPDATE
	);

	private function getConnection() {
		$ch = curl_init();
		curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
		curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
		curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
		curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
		curl_setopt($ch, CURLOPT_USERPWD, $this->appCfg['baculum']['login'] . ':' . $this->appCfg['baculum']['password']);
		return $ch;
	}

	private function getAPIHeaders() {
		$headers = array(
			'X-Baculum-API: ' . self::API_VERSION,
			'X-Baculum-User: ' . $this->Application->User->getName(),
			'X-Baculum-Pwd: ' . $this->Application->User->getPwd(),
			'Accept: application/json'
		);
		return $headers;
	}

	public function init($config) {
		$this->initSessionCache();
		$this->appCfg = $this->Application->getModule('configuration')->getApplicationConfig();
	}

	private function getURL() {
		$protocol = !empty($_SERVER['HTTPS']) ? 'https' : 'http';
		$host = $_SERVER['SERVER_NAME'];
		$port = $_SERVER['SERVER_PORT'];
		$urlPrefix = $this->Application->getModule('friendly-url')->getUrlPrefix();
		$url = sprintf('%s://%s:%d%s/', $protocol, $host, $port, $urlPrefix);
		return $url;
	}

	private function setParamsToUrl(&$url) {
		$url .= (preg_match('/\?/', $url) === 1 ? '&' : '?' ) . 'director=' . ((array_key_exists('director', $_SESSION)) ? $_SESSION['director'] : '');
		$this->Application->getModule('logging')->log(__FUNCTION__, PHP_EOL . PHP_EOL . 'EXECUTE URL ==> ' . $url . ' <==' . PHP_EOL . PHP_EOL, Logging::CATEGORY_APPLICATION, __FILE__, __LINE__);
	}

	/**
	 * API REQUESTS METHODS (get, set, create, delete)
	 */

	public function get(array $params, $use_cache = false) {
		$cached = null;
		$ret = null;
		if ($use_cache === true) {
			$cached = $this->getSessionCache($params);
		}
		if (!is_null($cached)) {
			$ret = $cached;
		} else {
			$url = $this->getURL() . implode('/', $params);
			$this->setParamsToUrl($url);
			$ch = $this->getConnection();
			curl_setopt($ch, CURLOPT_URL, $url);
			curl_setopt($ch, CURLOPT_HTTPHEADER, $this->getAPIHeaders());
			$result = curl_exec($ch);
			curl_close($ch);
			$ret = $this->preParseOutput($result);
			if ($use_cache === true && $ret->error === 0) {
				$this->setSessionCache($params, $ret);
			}
		}
		return $ret;
	}

	public function set(array $params, array $options) {
		$url = $this->getURL() . implode('/', $params);
		$this->setParamsToUrl($url);
		$data = http_build_query(array('update' => $options));
		$ch = $this->getConnection();
		curl_setopt($ch, CURLOPT_URL, $url);
		curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'PUT');
		curl_setopt($ch, CURLOPT_HTTPHEADER, array_merge($this->getAPIHeaders(), array('X-HTTP-Method-Override: PUT', 'Content-Length: ' . strlen($data), 'Expect:')));
		curl_setopt($ch, CURLOPT_POST, true);
		curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
		$result = curl_exec($ch);
		curl_close($ch);
		return $this->preParseOutput($result);
	}

	public function create(array $params, array $options) {
		$url = $this->getURL() . implode('/', $params);
		$this->setParamsToUrl($url);
		$data = http_build_query(array('create' => $options));
		$ch = $this->getConnection();
		curl_setopt($ch, CURLOPT_URL, $url);
		curl_setopt($ch, CURLOPT_HTTPHEADER, array_merge($this->getAPIHeaders(), array('Expect:')));
		curl_setopt($ch, CURLOPT_POST, true);
		curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
		$result = curl_exec($ch);
		curl_close($ch);
		return $this->preParseOutput($result);
	}

	public function remove(array $params) {
		$url = $this->getURL() . implode('/', $params);
		$this->setParamsToUrl($url);
		$ch = $this->getConnection();
		curl_setopt($ch, CURLOPT_URL, $url);
		curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'DELETE');
		curl_setopt($ch, CURLOPT_HTTPHEADER, array_merge($this->getAPIHeaders(), array('X-HTTP-Method-Override: DELETE')));
		$result = curl_exec($ch);
		curl_close($ch);
		return $this->preParseOutput($result);
	}

	private function preParseOutput($result) {
		$this->Application->getModule('logging')->log(__FUNCTION__, $result, Logging::CATEGORY_APPLICATION, __FILE__, __LINE__);
		$resource = json_decode($result);
		$error = null;
		if(is_object($resource) && property_exists($resource, 'error')) {
			if(!in_array($resource->error, $this->allowedErrors)) {
				$error = $resource->error;
			}
		} else {
			$error = AuthorizationError::ERROR_AUTHORIZATION_TO_WEBGUI_PROBLEM;
		}

		$this->Application->getModule('logging')->log(__FUNCTION__, $resource, Logging::CATEGORY_APPLICATION, __FILE__, __LINE__);
		if(!is_null($error)) {
			// Note! Redirection to error page takes place here.
			$this->Response->redirect($this->Service->constructUrl('BaculumError',array('error' => $error), false));
		}

		return $resource;
	}

	public function initSessionCache($force = false) {
		if (!isset($_SESSION) || !array_key_exists('cache', $_SESSION) || !is_array($_SESSION['cache']) || $force === true) {
			$_SESSION['cache'] = array();
		}
	}

	private function getSessionCache(array $params) {
		$cached = null;
		$key = $this->getSessionKey($params);
		if ($this->isSessionValue($key)) {
			$cached = $_SESSION['cache'][$key];
		}
		return $cached;
	}

	private function setSessionCache(array $params, $value) {
		$key = $this->getSessionKey($params);
		$_SESSION['cache'][$key] = $value;
	}

	private function getSessionKey(array $params) {
		$key = implode(';', $params);
		$key = base64_encode($key);
		return $key;
	}

	private function isSessionValue($key) {
		$is_value = array_key_exists($key, $_SESSION['cache']);
		return $is_value;
	}
}
?>