<?php
/**
* @package VikBooking
* @subpackage core
* @author E4J s.r.l.
* @copyright Copyright (C) 2021 E4J s.r.l. All Rights Reserved.
* @license http://www.gnu.org/licenses/gpl-2.0.html GNU/GPL
* @link https://vikwp.com
*/
// No direct access
defined('ABSPATH') or die('No script kiddies please!');
/**
* Wraps the instructions used to restore a backup.
*
* @since 1.5
*/
class VBOBackupImportDirector
{
/**
* The path of the backup (folder).
*
* @var string
*/
private $path;
/**
* The minimum requireed version to use while restoring a backup.
*
* @var string
*/
private $version;
/**
* Class constructor.
*
* @param string $path The archive path.
*/
public function __construct($path)
{
$this->path = rtrim($path, DIRECTORY_SEPARATOR);
}
/**
* Sets the version of the manifest.
*
* @param string $version
*
* @return self This object to support chaining.
*/
public function setVersion($version)
{
$this->version = $version;
return $this;
}
/**
* Executes the restore process.
*
* @return void
*
* @throws Exception
*/
public function process()
{
// obtain manifest object
$manifest = $this->parseManifest();
// make sure the backup version is compatible with the current one
$this->validateVersion($manifest);
/** @var VBOPlatformDispatcherInterface */
$dispatcher = VBOFactory::getPlatform()->getDispatcher();
/**
* Trigger event to allow third party plugins to extend the backup import.
* This hook triggers before processing the import of an existing backup.
*
* It is possible to throw an exception to prevent the import process.
*
* @param object $manifest The backup manifest.
* @param string $path The path of the backup archive (uncompressed).
*
* @return void
*
* @since 1.5
*
* @throws Exception
*/
$dispatcher->trigger('onBeforeImportBackupVikBooking', [$manifest, $this->path]);
// execute the uninstallation rules
$this->uninstall($manifest);
// execute the installation rules
$this->install($manifest);
/**
* Trigger event to allow third party plugins to extend the backup import.
* This hook triggers after processing the import of an existing backup.
*
* It is possible to throw an exception to prevent the import process.
*
* @param object $manifest The backup manifest.
* @param string $path The path of the backup archive (uncompressed).
*
* @return void
*
* @since 1.5
*
* @throws Exception
*/
$dispatcher->trigger('onAfterImportBackupVikBooking', [$manifest, $this->path]);
}
/**
* Helper method used to parse the manifest file contained
* within the backup archive.
*
* @return object
*
* @throws Exception
*/
protected function parseManifest()
{
// create file
$file = $this->path . DIRECTORY_SEPARATOR . 'manifest.json';
if (!JFile::exists($file))
{
$path_folders = JFolder::folders($this->path);
if ($path_folders)
{
// update path to manifest file
$this->path .= DIRECTORY_SEPARATOR . $path_folders[0];
$file = $this->path . DIRECTORY_SEPARATOR . 'manifest.json';
}
}
// make sure the manifest exists
if (!JFile::exists($file))
{
// manifest not found
throw new Exception('The backup does not include a manifest file', 404);
}
$manifest = '';
// open file pointer
$fp = fopen($file, 'r');
while (!feof($fp))
{
// read buffer
$manifest .= fread($fp, 8192);
}
// close file pointer
fclose($fp);
// decode the manifest
$manifest = json_decode($manifest);
if (!is_object($manifest))
{
throw new Exception('The backup manifest is not valid', 500);
}
return $manifest;
}
/**
* Checks whether the version of the backup is compatible with the current
* version of the software.
*
* @param object $manifest The backup manifest.
*
* @return boolean True if compatible.
*
* @throws Exception
*/
protected function validateVersion($manifest)
{
if (empty($manifest->application) || $manifest->application !== 'Vik Booking')
{
// application is missing
throw new Exception("Application is missing", 500);
}
$application = $manifest->application;
// get the identifier of the current platform
$platform = defined('ABSPATH') ? 'wordpress' : 'joomla';
// check whether the manifest specifies a custom version for the current platform
if (isset($manifest->platforms->{$platform}))
{
// append platform to program name
$application .= ' ' . $platform;
// override manifest with specific instructions for the current platform
$manifest = $manifest->platforms->{$platform};
}
if (empty($manifest->version))
{
// version not found
throw new Exception("Version not found", 500);
}
// check whether the version signature has been specified by the backup
if (isset($manifest->signature))
{
// validate version integrity
$signature = md5($application . ' ' . $manifest->version);
if ($signature !== $manifest->signature)
{
// the signature doesn't matche
throw new Exception('Signature mismatch', 500);
}
}
// first of all, make sure the backup version is equals or higher than the
// minimum required version
if (version_compare($manifest->version, $this->version, '<'))
{
// the manifest version is lower than the minimum required version
throw new Exception(sprintf('The backup version (%s) is not compatible with the minimum required version (%s)', $manifest->version, $this->version), 500);
}
// then check whether the current version is equals of higher than the backup version
if (version_compare(VIKBOOKING_SOFTWARE_VERSION, $manifest->version, '<')) {
// the software version is lower than the backup version
throw new Exception(sprintf('The software version (%s) is not compatible with the backup version (%s)', VIKBOOKING_SOFTWARE_VERSION, $manifest->version), 500);
}
return true;
}
/**
* Executes the uninstallation queries.
*
* @param object $manifest The backup manifest.
*
* @return void
*/
protected function uninstall($manifest)
{
// look for uninstall queries
if (!isset($manifest->uninstall))
{
// nothing to execute
return;
}
$dbo = JFactory::getDbo();
// iterate queries to clean any existing records
foreach ((array) $manifest->uninstall as $q)
{
// launch query
$dbo->setQuery($q);
$dbo->execute();
}
}
/**
* Executes the installation rules.
*
* @param object $manifest The backup manifest.
*
* @return void
*/
protected function install($manifest)
{
// look for installers
if (!isset($manifest->installers))
{
// nothing to install...
return;
}
$dispatcher = VBOFactory::getPlatform()->getDispatcher();
// iterate installers
foreach ((array) $manifest->installers as $install)
{
if (empty($install->role))
{
// install role not found, cannot proceed
throw new Exception('Missing import backup role', 500);
}
// extract import data from rule
$data = isset($install->data) ? $install->data : null;
/**
* Trigger event to allow third party plugins to implement at runtime new import backup rules.
*
* It is possible to throw an exception to abort the import process.
*
* @param string $role The identifier of the import rule.
* @param mixed $options The instructions of the backup import rule.
*
* @return boolean True in case the rule has been dispatched, false (or null) to let the
* system uses one of the pre-installed rules.
*
* @since 1.5
*
* @throws Exception
*/
$executed = $dispatcher->filter('onExecuteImportBackupRuleVikBooking', [$install->role, $data]);
// check whether the rule has been already dispatched by a plugin
if (!in_array(true, $executed))
{
// dispatch one of the system rules
$this->loadRule($install->role)->execute($data);
}
}
}
/**
* Creates a new import rule.
*
* @param string $rule The identifier of the rule to create.
*
* @return VBOBackupImportRule
*
* @throws Exception
*/
public function loadRule($rule)
{
// build class name
$classname = preg_replace("/_/", ' ', $rule);
$classname = preg_replace("/\s+/", '', ucwords($classname));
$classname = 'VBOBackupImportRule' . $classname;
// make sure the rule class exists
if (!class_exists($classname))
{
// class not found
throw new Exception(sprintf('Cannot find [%s] import rule class', $classname), 404);
}
// create new rule
$rule = new $classname($this->path);
// make sure we have a valid instance
if (!$rule instanceof VBOBackupImportRule)
{
throw new Exception(sprintf('The import rule [%s] is not a valid instance', $classname), 500);
}
// create the rule
return $rule;
}
}