<?php

namespace wcf\system\package;

use wcf\data\application\Application;
use wcf\data\application\ApplicationEditor;
use wcf\data\devtools\project\DevtoolsProjectAction;
use wcf\data\language\category\LanguageCategory;
use wcf\data\language\LanguageEditor;
use wcf\data\language\LanguageList;
use wcf\data\option\OptionEditor;
use wcf\data\package\installation\queue\PackageInstallationQueue;
use wcf\data\package\installation\queue\PackageInstallationQueueEditor;
use wcf\data\package\Package;
use wcf\data\package\PackageEditor;
use wcf\data\user\User;
use wcf\data\user\UserAction;
use wcf\system\application\ApplicationHandler;
use wcf\system\cache\builder\TemplateListenerCodeCacheBuilder;
use wcf\system\cache\CacheHandler;
use wcf\system\database\statement\PreparedStatement;
use wcf\system\database\util\PreparedStatementConditionBuilder;
use wcf\system\devtools\DevtoolsSetup;
use wcf\system\event\EventHandler;
use wcf\system\exception\ImplementationException;
use wcf\system\exception\SystemException;
use wcf\system\form\container\GroupFormElementContainer;
use wcf\system\form\container\MultipleSelectionFormElementContainer;
use wcf\system\form\element\MultipleSelectionFormElement;
use wcf\system\form\element\TextInputFormElement;
use wcf\system\form\FormDocument;
use wcf\system\language\LanguageFactory;
use wcf\system\package\plugin\IPackageInstallationPlugin;
use wcf\system\request\LinkHandler;
use wcf\system\request\RouteHandler;
use wcf\system\setup\IFileHandler;
use wcf\system\setup\Installer;
use wcf\system\style\StyleHandler;
use wcf\system\user\storage\UserStorageHandler;
use wcf\system\WCF;
use wcf\util\CryptoUtil;
use wcf\util\FileUtil;
use wcf\util\HeaderUtil;
use wcf\util\JSON;
use wcf\util\StringUtil;

/**
 * PackageInstallationDispatcher handles the whole installation process.
 *
 * @author  Alexander Ebert
 * @copyright   2001-2019 WoltLab GmbH
 * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
 * @package WoltLabSuite\Core\System\Package
 */
class PackageInstallationDispatcher
{
    /**
     * current installation type
     * @var string
     */
    protected $action = '';

    /**
     * instance of PackageArchive
     * @var PackageArchive
     */
    public $archive;

    /**
     * instance of PackageInstallationNodeBuilder
     * @var PackageInstallationNodeBuilder
     */
    public $nodeBuilder;

    /**
     * instance of Package
     * @var Package
     */
    public $package;

    /**
     * instance of PackageInstallationQueue
     * @var PackageInstallationQueue
     */
    public $queue;

    /**
     * default name of the config file
     * @var string
     */
    const CONFIG_FILE = 'app.config.inc.php';

    /**
     * data of previous package in queue
     * @var string[]
     */
    protected $previousPackageData;

    /**
     * Creates a new instance of PackageInstallationDispatcher.
     *
     * @param PackageInstallationQueue $queue
     */
    public function __construct(PackageInstallationQueue $queue)
    {
        $this->queue = $queue;
        $this->nodeBuilder = new PackageInstallationNodeBuilder($this);

        $this->action = $this->queue->action;
    }

    /**
     * Sets data of previous package in queue.
     *
     * @param string[] $packageData
     */
    public function setPreviousPackage(array $packageData)
    {
        $this->previousPackageData = $packageData;
    }

    /**
     * Installs node components and returns next node.
     *
     * @param string $node
     * @return  PackageInstallationStep
     * @throws      SystemException
     */
    public function install($node)
    {
        $nodes = $this->nodeBuilder->getNodeData($node);
        if (empty($nodes)) {
            // guard against possible issues with empty instruction blocks, including
            // these blocks that contain no valid instructions at all (e.g. typo from
            // copy & paste)
            throw new SystemException(
                "Failed to retrieve nodes for identifier '{$node}', the query returned no results."
            );
        }

        // invoke node-specific actions
        $step = null;
        foreach ($nodes as $data) {
            $nodeData = \unserialize($data['nodeData']);
            $this->logInstallationStep($data);

            switch ($data['nodeType']) {
                case 'package':
                    $step = $this->installPackage($nodeData);
                    break;

                case 'pip':
                    $step = $this->executePIP($nodeData);
                    break;

                case 'optionalPackages':
                    $step = $this->selectOptionalPackages($node, $nodeData);
                    break;

                default:
                    exit("Unknown node type: '" . $data['nodeType'] . "'");
                    break;
            }

            if ($step->splitNode()) {
                $log = 'split node';
                if ($step->getException() !== null && $step->getException()->getMessage()) {
                    $log .= ': ' . $step->getException()->getMessage();
                }

                $this->logInstallationStep($data, $log);
                $this->nodeBuilder->cloneNode($node, $data['sequenceNo']);
                break;
            }
        }

        // mark node as completed
        $this->nodeBuilder->completeNode($node);

        // assign next node
        $node = $this->nodeBuilder->getNextNode($node);
        $step->setNode($node);

        // perform post-install/update actions
        if ($node == '') {
            $this->logInstallationStep([], 'start cleanup');

            // update "last update time" option
            $sql = "UPDATE  wcf" . WCF_N . "_option
                    SET     optionValue = ?
                    WHERE   optionName = ?";
            $statement = WCF::getDB()->prepareStatement($sql);
            $statement->execute([
                TIME_NOW,
                'last_update_time',
            ]);

            // update options.inc.php
            OptionEditor::resetCache();

            if ($this->action == 'install') {
                // save localized package infos
                $this->saveLocalizedPackageInfos();

                // remove all cache files after WCFSetup
                if (!PACKAGE_ID) {
                    CacheHandler::getInstance()->flushAll();

                    $sql = "UPDATE  wcf" . WCF_N . "_option
                            SET     optionValue = ?
                            WHERE   optionName = ?";
                    $statement = WCF::getDB()->prepareStatement($sql);

                    $statement->execute([
                        StringUtil::getUUID(),
                        'wcf_uuid',
                    ]);

                    if (\file_exists(WCF_DIR . 'cookiePrefix.txt')) {
                        $statement->execute([
                            COOKIE_PREFIX,
                            'cookie_prefix',
                        ]);

                        @\unlink(WCF_DIR . 'cookiePrefix.txt');
                    }

                    $user = new User(1);
                    $statement->execute([
                        $user->username,
                        'mail_from_name',
                    ]);
                    $statement->execute([
                        $user->email,
                        'mail_from_address',
                    ]);
                    $statement->execute([
                        $user->email,
                        'mail_admin_address',
                    ]);

                    $statement->execute([
                        // We do not use the cache-timing safe class Hex, because we run the
                        // function during the setup.
                        $signatureSecret = \bin2hex(\random_bytes(20)),
                        'signature_secret',
                    ]);
                    \define('SIGNATURE_SECRET', $signatureSecret);
                    HeaderUtil::setCookie(
                        'user_session',
                        // We do not use the cache-timing safe class Hex, because we run the
                        // function during the setup.
                        CryptoUtil::createSignedString(
                            \pack(
                                'CA20C',
                                1,
                                \hex2bin(WCF::getSession()->sessionID),
                                0
                            )
                        )
                    );

                    if (WCF::getSession()->getVar('__wcfSetup_developerMode')) {
                        $statement->execute([
                            1,
                            'enable_debug_mode',
                        ]);
                        $statement->execute([
                            'public',
                            'exception_privacy',
                        ]);
                        $statement->execute([
                            'debugFolder',
                            'mail_send_method',
                        ]);
                        $statement->execute([
                            1,
                            'enable_developer_tools',
                        ]);
                        $statement->execute([
                            1,
                            'log_missing_language_items',
                        ]);

                        foreach (DevtoolsSetup::getInstance()->getOptionOverrides() as $optionName => $optionValue) {
                            $statement->execute([
                                $optionValue,
                                $optionName,
                            ]);
                        }

                        foreach (DevtoolsSetup::getInstance()->getUsers() as $newUser) {
                            try {
                                (new UserAction([], 'create', [
                                    'data' => [
                                        'email' => $newUser['email'],
                                        'password' => $newUser['password'],
                                        'username' => $newUser['username'],
                                    ],
                                    'groups' => [
                                        1,
                                        3,
                                    ],
                                ]))->executeAction();
                            } catch (SystemException $e) {
                                // ignore errors due to event listeners missing at this
                                // point during installation
                            }
                        }

                        if (($importPath = DevtoolsSetup::getInstance()->getDevtoolsImportPath()) !== '') {
                            (new DevtoolsProjectAction([], 'quickSetup', [
                                'path' => $importPath,
                            ]))->executeAction();
                        }
                    }

                    if (WCF::getSession()->getVar('__wcfSetup_imagick')) {
                        $statement->execute([
                            'imagick',
                            'image_adapter_type',
                        ]);
                    }

                    // update options.inc.php
                    OptionEditor::resetCache();

                    WCF::getSession()->register('__wcfSetup_completed', true);
                }

                // rebuild application paths
                ApplicationHandler::rebuild();
            }

            // remove template listener cache
            TemplateListenerCodeCacheBuilder::getInstance()->reset();

            // reset language cache
            LanguageFactory::getInstance()->clearCache();
            LanguageFactory::getInstance()->deleteLanguageCache();

            // reset stylesheets
            StyleHandler::resetStylesheets();

            // clear user storage
            UserStorageHandler::getInstance()->clear();

            // rebuild config files for affected applications
            $sql = "SELECT      package.packageID
                    FROM        wcf" . WCF_N . "_package_installation_queue queue,
                                wcf" . WCF_N . "_package package
                    WHERE       queue.processNo = ?
                            AND package.packageID = queue.packageID
                            AND package.isApplication = ?";
            $statement = WCF::getDB()->prepareStatement($sql);
            $statement->execute([
                $this->queue->processNo,
                1,
            ]);
            while ($row = $statement->fetchArray()) {
                Package::writeConfigFile($row['packageID']);
            }

            EventHandler::getInstance()->fireAction($this, 'postInstall');

            // remove archives
            $sql = "SELECT  archive
                    FROM    wcf" . WCF_N . "_package_installation_queue
                    WHERE   processNo = ?";
            $statement = WCF::getDB()->prepareStatement($sql);
            $statement->execute([$this->queue->processNo]);
            while ($row = $statement->fetchArray()) {
                @\unlink($row['archive']);
            }

            // delete queues
            $sql = "DELETE FROM wcf" . WCF_N . "_package_installation_queue
                    WHERE       processNo = ?";
            $statement = WCF::getDB()->prepareStatement($sql);
            $statement->execute([$this->queue->processNo]);

            $this->logInstallationStep([], 'finished cleanup');
        }

        return $step;
    }

    /**
     * Logs an installation step.
     *
     * @param array $node data of the executed node
     * @param string $log optional additional log text
     */
    protected function logInstallationStep(array $node = [], $log = '')
    {
        $logEntry = "[" . TIME_NOW . "]\n";
        if (!empty($node)) {
            $logEntry .= 'sequenceNo: ' . $node['sequenceNo'] . "\n";
            $logEntry .= 'nodeType: ' . $node['nodeType'] . "\n";
            $logEntry .= "nodeData:\n";

            $nodeData = \unserialize($node['nodeData']);
            foreach ($nodeData as $index => $value) {
                $logEntry .= "\t" . $index . ': ' . (!\is_object($value) && !\is_array($value) ? $value : JSON::encode($value)) . "\n";
            }
        }

        if ($log) {
            $logEntry .= 'additional information: ' . $log . "\n";
        }

        $logEntry .= \str_repeat('-', 30) . "\n\n";

        \file_put_contents(
            WCF_DIR . 'log/' . \date('Y-m-d', TIME_NOW) . '-update-' . $this->queue->queueID . '.txt',
            $logEntry,
            \FILE_APPEND
        );
    }

    /**
     * Returns current package archive.
     *
     * @return  PackageArchive
     */
    public function getArchive()
    {
        if ($this->archive === null) {
            // check if we're doing an iterative update of the same package
            if (
                $this->previousPackageData !== null
                && $this->getPackage()->package == $this->previousPackageData['package']
            ) {
                if (
                    Package::compareVersion(
                        $this->getPackage()->packageVersion,
                        $this->previousPackageData['packageVersion'],
                        '<'
                    )
                ) {
                    // fake package to simulate the package version required by current archive
                    $this->getPackage()->setPackageVersion($this->previousPackageData['packageVersion']);
                }
            }

            $this->archive = new PackageArchive($this->queue->archive, $this->getPackage());

            if (FileUtil::isURL($this->archive->getArchive())) {
                // get return value and update entry in
                // package_installation_queue with this value
                $archive = $this->archive->downloadArchive();
                $queueEditor = new PackageInstallationQueueEditor($this->queue);
                $queueEditor->update(['archive' => $archive]);
            }

            $this->archive->openArchive();
        }

        return $this->archive;
    }

    /**
     * Installs current package.
     *
     * @param mixed[] $nodeData
     * @return  PackageInstallationStep
     * @throws  SystemException
     */
    protected function installPackage(array $nodeData)
    {
        $installationStep = new PackageInstallationStep();

        // check requirements
        if (!empty($nodeData['requirements'])) {
            foreach ($nodeData['requirements'] as $package => $requirementData) {
                // get existing package
                if ($requirementData['packageID']) {
                    $sql = "SELECT  packageName, packageVersion
                            FROM    wcf" . WCF_N . "_package
                            WHERE   packageID = ?";
                    $statement = WCF::getDB()->prepareStatement($sql);
                    $statement->execute([$requirementData['packageID']]);
                } else {
                    // try to find matching package
                    $sql = "SELECT  packageName, packageVersion
                            FROM    wcf" . WCF_N . "_package
                            WHERE   package = ?";
                    $statement = WCF::getDB()->prepareStatement($sql);
                    $statement->execute([$package]);
                }
                $row = $statement->fetchArray();

                // package is required but not available
                if ($row === false) {
                    throw new SystemException("Package '" . $package . "' is required by '" . $nodeData['packageName'] . "', but is neither installed nor shipped.");
                }

                // check version requirements
                if ($requirementData['minVersion']) {
                    if (Package::compareVersion($row['packageVersion'], $requirementData['minVersion']) < 0) {
                        throw new SystemException("Package '" . $nodeData['packageName'] . "' requires package '" . $row['packageName'] . "' in version '" . $requirementData['minVersion'] . "', but only version '" . $row['packageVersion'] . "' is installed");
                    }
                }
            }
        }
        unset($nodeData['requirements']);

        $applicationDirectory = '';
        if (isset($nodeData['applicationDirectory'])) {
            $applicationDirectory = $nodeData['applicationDirectory'];
            unset($nodeData['applicationDirectory']);
        }

        // update package
        if ($this->queue->packageID) {
            $packageEditor = new PackageEditor(new Package($this->queue->packageID));
            unset($nodeData['installDate']);
            $packageEditor->update($nodeData);

            // delete old excluded packages
            $sql = "DELETE FROM wcf" . WCF_N . "_package_exclusion
                    WHERE       packageID = ?";
            $statement = WCF::getDB()->prepareStatement($sql);
            $statement->execute([$this->queue->packageID]);

            // delete old compatibility versions
            $sql = "DELETE FROM wcf" . WCF_N . "_package_compatibility
                    WHERE       packageID = ?";
            $statement = WCF::getDB()->prepareStatement($sql);
            $statement->execute([$this->queue->packageID]);

            // delete old requirements and dependencies
            $sql = "DELETE FROM wcf" . WCF_N . "_package_requirement
                    WHERE       packageID = ?";
            $statement = WCF::getDB()->prepareStatement($sql);
            $statement->execute([$this->queue->packageID]);
        } else {
            // create package entry
            $package = $this->createPackage($nodeData);

            // update package id for current queue
            $queueEditor = new PackageInstallationQueueEditor($this->queue);
            $queueEditor->update(['packageID' => $package->packageID]);

            // reload queue
            $this->queue = new PackageInstallationQueue($this->queue->queueID);
            $this->package = null;

            if ($package->isApplication) {
                $host = \str_replace(RouteHandler::getProtocol(), '', RouteHandler::getHost());
                $path = RouteHandler::getPath(['acp']);

                $isTainted = 1;
                if ($this->getPackage()->package == 'com.woltlab.wcf') {
                    // com.woltlab.wcf is special, because promptPackageDir() will not be executed.
                    $isTainted = 0;
                }

                // insert as application
                ApplicationEditor::create([
                    'domainName' => $host,
                    'domainPath' => $path,
                    'cookieDomain' => $host,
                    'packageID' => $package->packageID,
                    'isTainted' => $isTainted,
                ]);
            }
        }

        // save excluded packages
        if (\count($this->getArchive()->getExcludedPackages())) {
            $sql = "INSERT INTO wcf" . WCF_N . "_package_exclusion
                                (packageID, excludedPackage, excludedPackageVersion)
                    VALUES      (?, ?, ?)";
            $statement = WCF::getDB()->prepareStatement($sql);

            foreach ($this->getArchive()->getExcludedPackages() as $excludedPackage) {
                $statement->execute([
                    $this->queue->packageID,
                    $excludedPackage['name'],
                    !empty($excludedPackage['version']) ? $excludedPackage['version'] : '',
                ]);
            }
        }

        // save compatible versions
        if (!empty($this->getArchive()->getCompatibleVersions())) {
            $sql = "INSERT INTO wcf" . WCF_N . "_package_compatibility
                                (packageID, version)
                    VALUES      (?, ?)";
            $statement = WCF::getDB()->prepareStatement($sql);

            foreach ($this->getArchive()->getCompatibleVersions() as $version) {
                $statement->execute([
                    $this->queue->packageID,
                    $version,
                ]);
            }
        }

        // insert requirements and dependencies
        $requirements = $this->getArchive()->getAllExistingRequirements();
        if (!empty($requirements)) {
            $sql = "INSERT INTO wcf" . WCF_N . "_package_requirement
                                (packageID, requirement)
                    VALUES      (?, ?)";
            $statement = WCF::getDB()->prepareStatement($sql);

            foreach ($requirements as $identifier => $possibleRequirements) {
                $requirement = \array_shift($possibleRequirements);

                $statement->execute([
                    $this->queue->packageID,
                    $requirement['packageID'],
                ]);
            }
        }

        if (
            $this->getPackage()->isApplication
            && $this->getPackage()->package != 'com.woltlab.wcf'
            && $this->getAction() == 'install'
            && empty($this->getPackage()->packageDir)
        ) {
            $document = $this->promptPackageDir($applicationDirectory);
            if ($document !== null && $document instanceof FormDocument) {
                $installationStep->setDocument($document);
            }

            $installationStep->setSplitNode();
        }

        return $installationStep;
    }

    /**
     * Creates a new package based on the given data and returns it.
     *
     * @param array $packageData
     * @return  Package
     * @since   5.2
     */
    protected function createPackage(array $packageData)
    {
        return PackageEditor::create($packageData);
    }

    /**
     * Saves the localized package info.
     */
    protected function saveLocalizedPackageInfos()
    {
        $package = new Package($this->queue->packageID);

        // localize package information
        $sql = "INSERT INTO wcf" . WCF_N . "_language_item
                            (languageID, languageItem, languageItemValue, languageCategoryID, packageID)
                VALUES      (?, ?, ?, ?, ?)";
        $statement = WCF::getDB()->prepareStatement($sql);

        // get language list
        $languageList = new LanguageList();
        $languageList->readObjects();

        // workaround for WCFSetup
        if (!PACKAGE_ID) {
            $sql = "SELECT  *
                    FROM    wcf" . WCF_N . "_language_category
                    WHERE   languageCategory = ?";
            $statement2 = WCF::getDB()->prepareStatement($sql);
            $statement2->execute(['wcf.acp.package']);
            $languageCategory = $statement2->fetchObject(LanguageCategory::class);
        } else {
            $languageCategory = LanguageFactory::getInstance()->getCategory('wcf.acp.package');
        }

        // save package name
        $this->saveLocalizedPackageInfo($statement, $languageList, $languageCategory, $package, 'packageName');

        // save package description
        $this->saveLocalizedPackageInfo($statement, $languageList, $languageCategory, $package, 'packageDescription');

        // update description and name
        $packageEditor = new PackageEditor($package);
        $packageEditor->update([
            'packageDescription' => 'wcf.acp.package.packageDescription.package' . $this->queue->packageID,
            'packageName' => 'wcf.acp.package.packageName.package' . $this->queue->packageID,
        ]);
    }

    /**
     * Saves a localized package info.
     *
     * @param PreparedStatement $statement
     * @param LanguageList $languageList
     * @param LanguageCategory $languageCategory
     * @param Package $package
     * @param string $infoName
     */
    protected function saveLocalizedPackageInfo(
        PreparedStatement $statement,
        $languageList,
        LanguageCategory $languageCategory,
        Package $package,
        $infoName
    ) {
        $infoValues = $this->getArchive()->getPackageInfo($infoName);

        // get default value for languages without specified information
        $defaultValue = '';
        if (isset($infoValues['default'])) {
            $defaultValue = $infoValues['default'];
        } elseif (isset($infoValues['en'])) {
            // fallback to English
            $defaultValue = $infoValues['en'];
        } elseif (isset($infoValues[WCF::getLanguage()->getFixedLanguageCode()])) {
            // fallback to the language of the current user
            $defaultValue = $infoValues[WCF::getLanguage()->getFixedLanguageCode()];
        } elseif ($infoName == 'packageName') {
            // fallback to the package identifier for the package name
            $defaultValue = $this->getArchive()->getPackageInfo('name');
        }

        foreach ($languageList as $language) {
            $value = $defaultValue;
            if (isset($infoValues[$language->languageCode])) {
                $value = $infoValues[$language->languageCode];
            }

            $statement->execute([
                $language->languageID,
                'wcf.acp.package.' . $infoName . '.package' . $package->packageID,
                $value,
                $languageCategory->languageCategoryID,
                1,
            ]);
        }
    }

    /**
     * Executes a package installation plugin.
     *
     * @param mixed[] $nodeData
     * @return  PackageInstallationStep
     * @throws  SystemException
     */
    protected function executePIP(array $nodeData)
    {
        $step = new PackageInstallationStep();

        if ($nodeData['pip'] == PackageArchive::VOID_MARKER) {
            return $step;
        }

        // fetch all pips associated with current PACKAGE_ID and include pips
        // previously installed by current installation queue
        $sql = "SELECT  pluginName, className
                FROM    wcf" . WCF_N . "_package_installation_plugin
                WHERE   pluginName = ?";
        $statement = WCF::getDB()->prepareStatement($sql);
        $statement->execute([$nodeData['pip']]);
        $row = $statement->fetchArray();

        // PIP is unknown
        if (!$row || (\strcmp($nodeData['pip'], $row['pluginName']) !== 0)) {
            throw new SystemException("unable to find package installation plugin '" . $nodeData['pip'] . "'");
        }

        // valdidate class definition
        $className = $row['className'];
        if (!\class_exists($className)) {
            throw new SystemException("unable to find class '" . $className . "'");
        }

        // set default value
        if (empty($nodeData['value'])) {
            $defaultValue = \call_user_func([$className, 'getDefaultFilename']);
            if ($defaultValue) {
                $nodeData['value'] = $defaultValue;
            }
        }

        $plugin = new $className($this, $nodeData);

        if (!($plugin instanceof IPackageInstallationPlugin)) {
            throw new ImplementationException($className, IPackageInstallationPlugin::class);
        }

        // execute PIP
        $document = null;
        try {
            $document = $plugin->{$this->action}();
        } catch (SplitNodeException $e) {
            $step->setSplitNode($e);
        }

        if ($document !== null && ($document instanceof FormDocument)) {
            $step->setDocument($document);
            $step->setSplitNode();
        }

        return $step;
    }

    /**
     * Displays a list to select optional packages or installs selection.
     *
     * @param string $currentNode
     * @param array $nodeData
     * @return  PackageInstallationStep
     */
    protected function selectOptionalPackages($currentNode, array $nodeData)
    {
        $installationStep = new PackageInstallationStep();

        $document = $this->promptOptionalPackages($nodeData);
        if ($document !== null && $document instanceof FormDocument) {
            $installationStep->setDocument($document);
            $installationStep->setSplitNode();
        } // insert new nodes for each package
        elseif (\is_array($document)) {
            // get target child node
            $node = $currentNode;
            $queue = $this->queue;
            $shiftNodes = false;

            foreach ($nodeData as $package) {
                if (\in_array($package['package'], $document)) {
                    // ignore uninstallable packages
                    if (!$package['isInstallable']) {
                        continue;
                    }

                    if (!$shiftNodes) {
                        $this->nodeBuilder->shiftNodes($currentNode, 'tempNode');
                        $shiftNodes = true;
                    }

                    $queue = PackageInstallationQueueEditor::create([
                        'parentQueueID' => $queue->queueID,
                        'processNo' => $this->queue->processNo,
                        'userID' => WCF::getUser()->userID,
                        'package' => $package['package'],
                        'packageName' => $package['packageName'],
                        'archive' => $package['archive'],
                        'action' => $queue->action,
                    ]);

                    $installation = new self($queue);
                    $installation->nodeBuilder->setParentNode($node);
                    $installation->nodeBuilder->buildNodes();
                    $node = $installation->nodeBuilder->getCurrentNode();
                } else {
                    // remove archive
                    @\unlink($package['archive']);
                }
            }

            // shift nodes
            if ($shiftNodes) {
                $this->nodeBuilder->shiftNodes('tempNode', $node);
            }
        }

        return $installationStep;
    }

    /**
     * Extracts files from .tar(.gz) archive and installs them
     *
     * @param string $targetDir
     * @param string $sourceArchive
     * @param IFileHandler $fileHandler
     * @return  Installer
     */
    public function extractFiles($targetDir, $sourceArchive, $fileHandler = null)
    {
        return new Installer($targetDir, $sourceArchive, $fileHandler);
    }

    /**
     * Returns current package.
     *
     * @return  \wcf\data\package\Package
     */
    public function getPackage()
    {
        if ($this->package === null) {
            $this->package = new Package($this->queue->packageID);
        }

        return $this->package;
    }

    /**
     * Prompts for a text input for package directory (applies for applications only)
     *
     * @param string $applicationDirectory
     * @return  FormDocument
     */
    protected function promptPackageDir($applicationDirectory)
    {
        // check for pre-defined directories originating from WCFSetup
        $directory = WCF::getSession()->getVar('__wcfSetup_directories');
        $abbreviation = Package::getAbbreviation($this->getPackage()->package);
        if ($directory !== null) {
            $directory = $directory[$abbreviation] ?? null;
        } elseif (
            ENABLE_ENTERPRISE_MODE
            && \defined('ENTERPRISE_MODE_APP_DIRECTORIES')
            && \is_array(ENTERPRISE_MODE_APP_DIRECTORIES)
        ) {
            $directory = ENTERPRISE_MODE_APP_DIRECTORIES[$abbreviation] ?? null;
        }

        if ($directory === null && !PackageInstallationFormManager::findForm($this->queue, 'packageDir')) {
            $container = new GroupFormElementContainer();
            $packageDir = new TextInputFormElement($container);
            $packageDir->setName('packageDir');
            $packageDir->setLabel(WCF::getLanguage()->get('wcf.acp.package.packageDir.input'));

            // check if there are packages installed in a parent
            // directory of WCF, or if packages are below it
            $sql = "SELECT  packageDir
                    FROM    wcf" . WCF_N . "_package
                    WHERE   packageDir <> ''";
            $statement = WCF::getDB()->prepareStatement($sql);
            $statement->execute();

            $isParent = null;
            while ($column = $statement->fetchColumn()) {
                if ($isParent !== null) {
                    continue;
                }

                if (\preg_match('~^\.\./[^\.]~', $column)) {
                    $isParent = false;
                } elseif (\mb_strpos($column, '.') !== 0) {
                    $isParent = true;
                }
            }

            $defaultPath = WCF_DIR;
            if ($isParent === false) {
                $defaultPath = \dirname(WCF_DIR);
            }
            if (!$applicationDirectory) {
                $applicationDirectory = Package::getAbbreviation($this->getPackage()->package);
            }
            $defaultPath = FileUtil::addTrailingSlash(FileUtil::unifyDirSeparator($defaultPath)) . $applicationDirectory . '/';

            $packageDir->setValue($defaultPath);
            $container->appendChild($packageDir);

            $document = new FormDocument('packageDir');
            $document->appendContainer($container);

            PackageInstallationFormManager::registerForm($this->queue, $document);

            return $document;
        } else {
            if ($directory !== null) {
                $document = null;
                $packageDir = $directory;
            } else {
                $document = PackageInstallationFormManager::getForm($this->queue, 'packageDir');
                $document->handleRequest();
                $packageDir = FileUtil::addTrailingSlash(FileUtil::getRealPath(FileUtil::unifyDirSeparator(
                    $document->getValue('packageDir')
                )));
                if ($packageDir === '/') {
                    $packageDir = '';
                }
            }

            if ($packageDir !== null) {
                // validate package dir
                if ($document !== null && \file_exists($packageDir . 'global.php')) {
                    $document->setError(
                        'packageDir',
                        WCF::getLanguage()->get('wcf.acp.package.packageDir.notAvailable')
                    );

                    return $document;
                }

                // set package dir
                $packageEditor = new PackageEditor($this->getPackage());
                $packageEditor->update([
                    'packageDir' => FileUtil::getRelativePath(WCF_DIR, $packageDir),
                ]);

                // determine domain path, in some environments (e.g. ISPConfig) the $_SERVER paths are
                // faked and differ from the real filesystem path
                if (PACKAGE_ID) {
                    $wcfDomainPath = ApplicationHandler::getInstance()->getWCF()->domainPath;
                } else {
                    $sql = "SELECT  domainPath
                            FROM    wcf" . WCF_N . "_application
                            WHERE   packageID = ?";
                    $statement = WCF::getDB()->prepareStatement($sql);
                    $statement->execute([1]);
                    $row = $statement->fetchArray();

                    $wcfDomainPath = $row['domainPath'];
                }

                $documentRoot = \substr(
                    FileUtil::unifyDirSeparator(WCF_DIR),
                    0,
                    -\strlen(FileUtil::unifyDirSeparator($wcfDomainPath))
                );
                $domainPath = FileUtil::getRelativePath($documentRoot, $packageDir);
                if ($domainPath === './') {
                    // `FileUtil::getRelativePath()` returns `./` if both paths lead to the same directory
                    $domainPath = '/';
                }

                $domainPath = FileUtil::addLeadingSlash($domainPath);

                // update application path and untaint application
                $application = new Application($this->getPackage()->packageID);
                $applicationEditor = new ApplicationEditor($application);
                $applicationEditor->update([
                    'domainPath' => $domainPath,
                    'isTainted' => 0,
                ]);

                // create directory and set permissions
                @\mkdir($packageDir, 0777, true);
                FileUtil::makeWritable($packageDir);
            }

            return;
        }
    }

    /**
     * Prompts a selection of optional packages.
     *
     * @param string[][] $packages
     * @return  mixed
     */
    protected function promptOptionalPackages(array $packages)
    {
        if (!PackageInstallationFormManager::findForm($this->queue, 'optionalPackages')) {
            $container = new MultipleSelectionFormElementContainer();
            $container->setName('optionalPackages');
            $container->setLabel(WCF::getLanguage()->get('wcf.acp.package.optionalPackages'));
            $container->setDescription(WCF::getLanguage()->get('wcf.acp.package.optionalPackages.description'));

            foreach ($packages as $package) {
                $optionalPackage = new MultipleSelectionFormElement($container);
                $optionalPackage->setName('optionalPackages');
                $optionalPackage->setLabel($package['packageName']);
                $optionalPackage->setValue($package['package']);
                $optionalPackage->setDescription($package['packageDescription']);
                if (!$package['isInstallable']) {
                    $optionalPackage->setDisabledMessage(
                        WCF::getLanguage()->get('wcf.acp.package.install.optionalPackage.missingRequirements')
                    );
                }

                $container->appendChild($optionalPackage);
            }

            $document = new FormDocument('optionalPackages');
            $document->appendContainer($container);

            PackageInstallationFormManager::registerForm($this->queue, $document);

            return $document;
        } else {
            $document = PackageInstallationFormManager::getForm($this->queue, 'optionalPackages');
            $document->handleRequest();

            return $document->getValue('optionalPackages');
        }
    }

    /**
     * Returns current package id.
     *
     * @return  int
     */
    public function getPackageID()
    {
        return $this->queue->packageID;
    }

    /**
     * Returns current package name.
     *
     * @return  string      package name
     * @since   3.0
     */
    public function getPackageName()
    {
        return $this->queue->packageName;
    }

    /**
     * Returns current package installation type.
     *
     * @return  string
     */
    public function getAction()
    {
        return $this->action;
    }

    /**
     * Opens the package installation queue and
     * starts the installation, update or uninstallation of the first entry.
     *
     * @param int $parentQueueID
     * @param int $processNo
     */
    public static function openQueue($parentQueueID = 0, $processNo = 0)
    {
        $conditions = new PreparedStatementConditionBuilder();
        $conditions->add("userID = ?", [WCF::getUser()->userID]);
        $conditions->add("parentQueueID = ?", [$parentQueueID]);
        if ($processNo != 0) {
            $conditions->add("processNo = ?", [$processNo]);
        }
        $conditions->add("done = ?", [0]);

        $sql = "SELECT      *
                FROM        wcf" . WCF_N . "_package_installation_queue
                " . $conditions . "
                ORDER BY    queueID ASC";
        $statement = WCF::getDB()->prepareStatement($sql);
        $statement->execute($conditions->getParameters());
        $packageInstallation = $statement->fetchArray();

        if (!isset($packageInstallation['queueID'])) {
            $url = LinkHandler::getInstance()->getLink('PackageList');
            HeaderUtil::redirect($url);

            exit;
        } else {
            $url = LinkHandler::getInstance()->getLink(
                'PackageInstallationConfirm',
                [],
                'queueID=' . $packageInstallation['queueID']
            );
            HeaderUtil::redirect($url);

            exit;
        }
    }

    /**
     * Checks the package installation queue for outstanding entries.
     *
     * @return  int
     */
    public static function checkPackageInstallationQueue()
    {
        $sql = "SELECT      queueID
                FROM        wcf" . WCF_N . "_package_installation_queue
                WHERE       userID = ?
                        AND parentQueueID = 0
                        AND done = 0
                ORDER BY    queueID ASC";
        $statement = WCF::getDB()->prepareStatement($sql);
        $statement->execute([WCF::getUser()->userID]);
        $row = $statement->fetchArray();

        if (!$row) {
            return 0;
        }

        return $row['queueID'];
    }

    /**
     * Executes post-setup actions.
     */
    public function completeSetup()
    {
        // remove archives
        $sql = "SELECT  archive
                FROM    wcf" . WCF_N . "_package_installation_queue
                WHERE   processNo = ?";
        $statement = WCF::getDB()->prepareStatement($sql);
        $statement->execute([$this->queue->processNo]);
        while ($row = $statement->fetchArray()) {
            @\unlink($row['archive']);
        }

        // delete queues
        $sql = "DELETE FROM wcf" . WCF_N . "_package_installation_queue
                WHERE       processNo = ?";
        $statement = WCF::getDB()->prepareStatement($sql);
        $statement->execute([$this->queue->processNo]);

        // clear language files once whole installation is completed
        LanguageEditor::deleteLanguageFiles();

        // reset all caches
        CacheHandler::getInstance()->flushAll();
    }

    /**
     * Updates queue information.
     */
    public function updatePackage()
    {
        if (empty($this->queue->packageName)) {
            $queueEditor = new PackageInstallationQueueEditor($this->queue);
            $queueEditor->update([
                'packageName' => $this->getArchive()->getLocalizedPackageInfo('packageName'),
            ]);

            // reload queue
            $this->queue = new PackageInstallationQueue($this->queue->queueID);
        }
    }

    /**
     * Validates specific php requirements.
     *
     * @param array $requirements
     * @return  mixed[][]
     */
    public static function validatePHPRequirements(array $requirements)
    {
        $errors = [];

        // validate php version
        if (isset($requirements['version'])) {
            $passed = false;
            if (\version_compare(\PHP_VERSION, $requirements['version'], '>=')) {
                $passed = true;
            }

            if (!$passed) {
                $errors['version'] = [
                    'required' => $requirements['version'],
                    'installed' => \PHP_VERSION,
                ];
            }
        }

        // validate extensions
        if (isset($requirements['extensions'])) {
            foreach ($requirements['extensions'] as $extension) {
                $passed = \extension_loaded($extension) ? true : false;

                if (!$passed) {
                    $errors['extension'][] = [
                        'extension' => $extension,
                    ];
                }
            }
        }

        // validate settings
        if (isset($requirements['settings'])) {
            foreach ($requirements['settings'] as $setting => $value) {
                $iniValue = \ini_get($setting);

                $passed = self::compareSetting($setting, $value, $iniValue);
                if (!$passed) {
                    $errors['setting'][] = [
                        'setting' => $setting,
                        'required' => $value,
                        'installed' => ($iniValue === false) ? '(unknown)' : $iniValue,
                    ];
                }
            }
        }

        // validate functions
        if (isset($requirements['functions'])) {
            foreach ($requirements['functions'] as $function) {
                $function = \mb_strtolower($function);

                $passed = self::functionExists($function);
                if (!$passed) {
                    $errors['function'][] = [
                        'function' => $function,
                    ];
                }
            }
        }

        // validate classes
        if (isset($requirements['classes'])) {
            foreach ($requirements['classes'] as $class) {
                $passed = false;

                // see: http://de.php.net/manual/en/language.oop5.basic.php
                if (\preg_match('~[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*.~', $class)) {
                    $globalClass = '\\' . $class;

                    if (\class_exists($globalClass, false)) {
                        $passed = true;
                    }
                }

                if (!$passed) {
                    $errors['class'][] = [
                        'class' => $class,
                    ];
                }
            }
        }

        return $errors;
    }

    /**
     * Validates if an function exists and is not blacklisted by suhosin extension.
     *
     * @param string $function
     * @return  bool
     * @see     http://de.php.net/manual/en/function.function-exists.php#77980
     */
    protected static function functionExists($function)
    {
        if (\extension_loaded('suhosin')) {
            $blacklist = @\ini_get('suhosin.executor.func.blacklist');
            if (!empty($blacklist)) {
                $blacklist = \explode(',', $blacklist);
                foreach ($blacklist as $disabledFunction) {
                    $disabledFunction = \mb_strtolower(StringUtil::trim($disabledFunction));

                    if ($function == $disabledFunction) {
                        return false;
                    }
                }
            }
        }

        return \function_exists($function);
    }

    /**
     * Compares settings, converting values into compareable ones.
     *
     * @param string $setting
     * @param string $value
     * @param mixed $compareValue
     * @return  bool
     */
    protected static function compareSetting($setting, $value, $compareValue)
    {
        if ($compareValue === false) {
            return false;
        }

        $value = \mb_strtolower($value);
        $trueValues = ['1', 'on', 'true'];
        $falseValues = ['0', 'off', 'false'];

        // handle values considered as 'true'
        if (\in_array($value, $trueValues)) {
            return $compareValue ? true : false;
        } // handle values considered as 'false'
        elseif (\in_array($value, $falseValues)) {
            return (!$compareValue) ? true : false;
        } elseif (!\is_numeric($value)) {
            $compareValue = self::convertShorthandByteValue($compareValue);
            $value = self::convertShorthandByteValue($value);
        }

        return ($compareValue >= $value) ? true : false;
    }

    /**
     * Converts shorthand byte values into an integer representing bytes.
     *
     * @param string $value
     * @return  int
     * @see     http://www.php.net/manual/en/faq.using.php#faq.using.shorthandbytes
     */
    protected static function convertShorthandByteValue($value)
    {
        // convert into bytes
        $lastCharacter = \mb_substr($value, -1);
        switch ($lastCharacter) {
            // gigabytes
            case 'g':
                return (int)$value * 1073741824;
                break;

            // megabytes
            case 'm':
                return (int)$value * 1048576;
                break;

            // kilobytes
            case 'k':
                return (int)$value * 1024;
                break;

            default:
                return $value;
                break;
        }
    }
}