<?php

// (c) Copyright by authors of the Tiki Wiki CMS Groupware Project
//
// All Rights Reserved. See copyright.txt for details and a complete list of authors.
// Licensed under the GNU LESSER GENERAL PUBLIC LICENSE. See license.txt for details.
// $Id$

use Tiki\FileGallery\File as TikiFile;

class H5PLib
{
    /**
     * Lib version, used for cache-busting of style and script file references.
     * Keeping track of the DB version.
     *
     * @since 1.0.0
     * @var string
     */
    const VERSION = '1.6.0';

    private $H5PTiki = null;

    private static $settings = null;

    /**
     * H5PLib constructor.
     * @throws Exception
     */
    public function __construct()
    {
        if (! extension_loaded('zip')) {
            throw new Exception(tr('PHP Zip extension not found, reqiuired for Feature H5P'));
        }
        $this->H5PTiki = \H5P_H5PTiki::get_h5p_instance('interface');
    }

    public function __destruct()
    {
    }

    /**
     * Triggered by the tiki.file.create event from filegallib
     *
     * @param array $args containing:
     *  - 'type' => 'file'
     *  - 'object' => $fileId
     *  - 'user' => $GLOBALS['user']
     *  - 'galleryId' => $galleryId
     *  - 'filetype' => $type
     *
     */
    public function handle_fileCreation($args)
    {
        if (! $this->H5PTiki->isSaving && $metadata = $this->getRequestMetadata($args)) {
            $validator = H5P_H5PTiki::get_h5p_instance('validator');

            if ($validator->isValidPackage()) {
                $storage = H5P_H5PTiki::get_h5p_instance('storage');
                $storage->savePackage(null, $args['object']);
            } else {
                // TODO: What to do if the file isn't a valid H5P? Seems a bit drastic to delete the file – but then again, why would we host broken files?
                // @unlink($interface->getUploadedH5pPath());

                Feedback::error(Feedback::get());
            }
        }
    }

    /**
     * Triggered by the tiki.file.update event from filegallib
     *
     * @param array $args containing:
     *  - 'type' => 'file'
     *  - 'object' => $fileId
     *  - 'user' => $GLOBALS['user']
     *  - 'galleryId' => $galleryId
     *  - 'filetype' => $type
     *
     */
    public function handle_fileUpdate($args)
    {
        if (! $this->H5PTiki->isSaving && isset($args['object']) && $metadata = $this->getRequestMetadata($args)) {
            $validator = H5P_H5PTiki::get_h5p_instance('validator');

            if ($validator->isValidPackage()) {
                $content = $this->loadContentFromFileId($args['object']);

                $storage = H5P_H5PTiki::get_h5p_instance('storage');
                $storage->savePackage($content, $args['object']);
            }
        }
    }

    /**
     * Triggered by the tiki.file.delete event from filegallib
     *
     * @param array $args containing:
     *  - 'type' => 'file'
     *  - 'object' => $fileId
     *  - 'user' => $GLOBALS['user']
     *  - 'galleryId' => $galleryId
     *  - 'filetype' => $type
     *
     */
    public function handle_fileDelete($args)
    {
        if (isset($args['object']) && $args['type'] === 'file') {
            $id = $this->getContentIdFromFileId($args['object']);

            if ($id) {
                // Remove the h5p contents
                $this->H5PTiki->deleteContentData($id);
            }
        }
    }

    /**
     * Get H5P content row from the Tiki fileId
     *
     * @param int $fileId
     *
     * @return array|bool
     */
    public function loadContentFromFileId($fileId)
    {
        global $prefs;

        $id = $this->getContentIdFromFileId($fileId);

        if ($id) {// Try to find content with $id.
            $core = \H5P_H5PTiki::get_h5p_instance('core');
            $content = $core->loadContent($id); // TODO: Is it possible to pass $fileId directly here to reduce the number of queries?

            if (is_array($content) && ! empty($content)) {
                // no error
                $content['language'] = substr($prefs['language'], 0, 2);    // TODO better
            }

            return $content;
        } else {
            return false;
        }
    }

    /**
     * @param int $fileId
     * @return bool|mixed
     */
    public function getContentIdFromFileId($fileId)
    {
        $tiki_h5p_contents = TikiDb::get()->table('tiki_h5p_contents');

        return $tiki_h5p_contents->fetchOne('id', ['file_id' => $fileId]);
    }

    private function getRequestMetadata($args)
    {
        $metadata = null;

        if ($this->isZipFile($args) && $zip = $this->getZipFile($args['object'])) {
            if ($manifest = $this->getH5PManifest($zip)) {
                $metadata = $this->getMetadata($manifest);
            }

            $zip->close();
        }

        return $metadata;
    }

    private function isZipFile($args)
    {
        if (! isset($args['filetype'])) {
            return false;
        }

        return in_array($args['filetype'], ['application/zip', 'application/x-zip', 'application/x-zip-compressed']);
    }

    private function getZipFile($fileId)
    {
        global $prefs, $tikipath;

        if (! class_exists('ZipArchive')) {
            Feedback::error(tra('PHP Class "ZipArchive" not found'));
        }

        $file = TikiFile::id($fileId);

        // make a copy of the h5p file for the validator to unpack (and eventually delete)
        $dest = $tikipath . 'temp/' . $file->filename;
        file_put_contents($dest, $file->getContents());

        /** @var ZipArchive $zip */
        $zip = new ZipArchive();
        $interface = H5P_H5PTiki::get_h5p_instance('interface');

        $filepath = $interface->getUploadedH5pPath($dest);

        if ($zip->open($filepath) === true) {
            return $zip;
        }
    }

    /**
     * @param ZipArchive $zip
     * @return mixed
     */
    private function getH5PManifest($zip)
    {
        return $zip->getFromName('h5p.json');
    }

    private function getMetadata($manifest)
    {

        return json_decode($manifest, false);
    }


    /**
     * Include settings and assets for the given content.
     *
     * @param array $content
     * @param boolean $no_cache
     * @return string Embed code
     */
    public function addAssets($content, $no_cache = false)
    {
        // Add core assets
        $this->addCoreAssets();

        // Detemine embed type
        $embed = H5PCore::determineEmbedType($content['embedType'], $content['library']['embedTypes']);

        // Make sure content isn't added twice
        $cid = 'cid-' . $content['id'];
        if (! isset(self::$settings['contents'][$cid])) {
            self::$settings['contents'][$cid] = $this->getContentSettings($content);
            $core = \H5P_H5PTiki::get_h5p_instance('core');

            // Get assets for this content
            $preloaded_dependencies = $core->loadContentDependencies($content['id'], 'preloaded');
            $files = $core->getDependenciesFiles($preloaded_dependencies);
            $this->alter_assets($files, $preloaded_dependencies, $embed);

            if ($embed === 'div') {
                $this->enqueueAssets($files);
            } elseif ($embed === 'iframe') {
                self::$settings['contents'][$cid]['scripts'] = $core->getAssetsUrls($files['scripts']);
                self::$settings['contents'][$cid]['styles'] = $core->getAssetsUrls($files['styles']);
            }
        }

        // Tiki JB note: I had to add this here to get the js files to be included,
        // the WP plugin doesn't use this here so i must be missing something else...
        $this->printSettings(self::$settings);

        if ($embed === 'div') {
            return '<div class="h5p-content" data-content-id="' . $content['id'] . '"></div>';
        } else {
            return '<div class="h5p-iframe-wrapper"><iframe id="h5p-iframe-' . $content['id'] . '" class="h5p-iframe" data-content-id="' . $content['id'] . '" style="height:1px" src="about:blank" frameBorder="0" scrolling="no"></iframe></div>';
        }
    }

    /**
     * Add the js and css files specified in the prefs
     *
     * @param array $dependencies
     * @param array $files scripts & styles
     * @param string $embed type
     */
    public function alter_assets(&$files, &$dependencies, $embed)
    {
        global $prefs, $base_url;

        // refactor dependency list
        $libraries = [];
        foreach ($dependencies as $dependency) {
            $libraries[$dependency['machineName']] = [
                'majorVersion' => $dependency['majorVersion'],
                'minorVersion' => $dependency['minorVersion'],
            ];
        }

        $prefsMap = [
            'h5p_custom_js_files' => 'scripts',
            'h5p_custom_css_files' => 'styles',
        ];

        foreach ($prefsMap as $pref => $type) {
            if (! empty($prefs[$pref])) {
                $additions = explode("\n", $prefs[$pref]);
                foreach ($additions as & $line) {
                    $line = explode(',', $line);
                }
                foreach ($additions as $addition) {
                    if ($addition[0] === '*' || isset($libraries[$addition[0]])) {
                        $version = $addition[2] ?? '1.0.0';
                        $filepath = $addition[1];
                        if (strpos(parse_url($filepath, PHP_URL_PATH), '/') !== 0) {
                            // relative path needs to be absolute to tiki base
                            $filepath = $base_url . $filepath;
                        }
                        $files[$type][] = (object) [
                            'path'    => $filepath,
                            'version' => "?ver=$version",    // Cache buster
                        ];
                    }
                }
            }
        }
    }

    /**
     * Set core JavaScript settings and add core assets.
     */
    public function addCoreAssets()
    {

        if (! empty(self::$settings)) {
            return; // Already added
        }

        self::$settings = $this->getCoreSettings();
        self::$settings['core'] = [
            'styles' => [],
            'scripts' => [],
        ];
        self::$settings['loadedJs'] = [];
        self::$settings['loadedCss'] = [];
        $TWV = new TWVersion();
        $cache_buster = '?ver=' . $TWV->version;

        $lib_url = 'vendor_bundled/vendor/h5p/h5p-core/';

        // Add core stylesheets
        foreach (H5PCore::$styles as $style) {
            self::$settings['core']['styles'][] = $lib_url . $style . $cache_buster;
            TikiLib::lib('header')->add_cssfile($lib_url . $style);
        }

        // Add core JavaScript
        foreach (H5PCore::$scripts as $script) {
            self::$settings['core']['scripts'][] = $lib_url . $script . $cache_buster;
            TikiLib::lib('header')->add_jsfile($lib_url . $script);
        }
    }

    /**
     * Get generic h5p settings
     */
    public function getCoreSettings()
    {
        global $user, $base_url, $prefs;

        $userId = TikiLib::lib('tiki')->get_user_id($user);

        $core = H5P_H5PTiki::get_h5p_instance('core');
        $h5p  = H5P_H5PTiki::get_h5p_instance('interface');

        $settings = [
            'baseUrl'            => $base_url,
            'url'                => $base_url . \H5P_H5PTiki::$h5p_path,
            'postUserStatistics' => ($prefs['h5p_track_user'] === 'y') && $userId,
            'ajax'               => [
                'setFinished'     => 'tiki-ajax_services.php?controller=h5p&action=results',
                'contentUserData' => 'tiki-ajax_services.php?controller=h5p&action=userdata&contentId=:contentId&dataType=:dataType&subContentId=:subContentId',
            ],
            'saveFreq'           => $prefs['h5p_save_content_state'] === 'y' ? $prefs['h5p_save_content_frequency'] : false,
            'siteUrl'            => $base_url,
            'l10n'               => [
                'H5P' => $core->getLocalization(),
            ],
            'hubIsEnabled'       => $prefs['h5p_hub_is_enabled'] === 'y',
            'reportingIsEnabled' => $prefs['h5p_enable_lrs_content_types'] === 'y',
            'libraryConfig'      => $h5p->getLibraryConfig(),
            'crossorigin'        => defined('H5P_CROSSORIGIN') ? H5P_CROSSORIGIN : null,
        ];

        if ($userId) {
            $settings['user'] = [
                'name' => $user,
                //'mail' => $userId->user_email, // TODO: Used in xAPI statements to uniquely identify the user across systems, i.e. if an LRS is used.
            ];
        }

        return $settings;
    }

    /**
     * Enqueue assets for content embedded by div.
     *
     * @param array $assets
     */
    public function enqueueAssets(&$assets)
    {
        $rel_url = \H5P_H5PTiki::$h5p_path;

        foreach ($assets['scripts'] as $script) {
            $url = $rel_url . $script->path . $script->version;
            if (! in_array($url, self::$settings['loadedJs'])) {
                self::$settings['loadedJs'][] = $url;
                TikiLib::lib('header')->add_jsfile($rel_url . $script->path);
            }
        }
        foreach ($assets['styles'] as $style) {
            $url = $rel_url . $style->path . $style->version;
            if (! in_array($url, self::$settings['loadedCss'])) {
                self::$settings['loadedCss'][] = $url;
                TikiLib::lib('header')->add_cssfile($rel_url . $style->path);
            }
        }
    }


    /**
     * Add H5P JavaScript settings to the bottom of the page.
     */
    public function addSettings()
    {
        if (self::$settings !== null) {
            $this->printSettings(self::$settings);
        }
    }

    /**
     * JSON encode and print the given H5P JavaScript settings.
     *
     * @param array $settings
     */
    public function printSettings($settings, $obj_name = 'H5PIntegration')
    {

        $json_settings = json_encode($settings);
        if ($json_settings !== false) {
            $headerlib = TikiLib::lib('header');
            if (! empty($headerlib->js['5h5p'])) {
                $headerlib->js['5h5p'] = [];    // clear previous plugins js as they are accumulative
            }
            $headerlib->add_js('var ' . $obj_name . ' = ' . $json_settings . ";\n", '5h5p');
        }
    }

    /**
     * Get added JavaScript settings.
     *
     * @return array
     */
    public function getSettings()
    {
        return self::$settings;
    }

    /**
     * Get settings for given content
     *
     * @since 1.5.0
     * @param array $content
     * @return array
     */
    public function getContentSettings($content)
    {
        global $prefs, $user;

        $core = \H5P_H5PTiki::get_h5p_instance('core');

        // Add global disable settings - odd, not found?
        //$content['disable'] |= $core->getGlobalDisable();

        $safe_parameters = $core->filterParameters($content);
        /*      if (has_action('h5p_alter_filtered_parameters')) {
                    // Parse the JSON parameters
                    $decoded_parameters = json_decode($safe_parameters);

                    /**
                     * Allows you to alter the H5P content parameters after they have been
                     * filtered. This hook only fires before view.
                     *
                     * @since 1.5.3
                     *
                     * @param object &$parameters
                     * @param string $libraryName
                     * @param int $libraryMajorVersion
                     * @param int $libraryMinorVersion
                     * /
                    do_action_ref_array('h5p_alter_filtered_parameters', array(&$decoded_parameters, $content['library']['name'], $content['library']['majorVersion'], $content['library']['minorVersion']));

                    // Stringify the JSON parameters
                    $safe_parameters = json_encode($decoded_parameters);
                }
        */

        $smarty = TikiLib::lib('smarty');
        $smarty->loadPlugin('smarty_function_service');
        $embedUrl = smarty_function_service([
            'controller' => 'h5p',
            'action' => 'embed',
            'fileId' => $content['file_id'],
        ], $smarty->getEmptyInternalTemplate());

        // Getting author's user id
        $userId = TikiLib::lib('tiki')->get_user_id($user);
        $author_id = (is_array($content) ? $content['user_id'] : $userId);

        // Add JavaScript settings for this content
        $settings = [
            'library' => H5PCore::libraryToString($content['library']),
            'jsonContent' => $safe_parameters,
            'fullScreen' => $content['library']['fullscreen'],
            'exportUrl' => ($prefs['h5p_export'] === 'y' ? 'tiki-download_file.php?fileId=' . $content['file_id'] : ''),
            'embedCode' => '<iframe src="' . $embedUrl . '" width=":w" height=":h" frameborder="0" allowfullscreen="allowfullscreen"></iframe>',
            'resizeCode' => '<script src="vendor_bundled/vendor/h5p/h5p-core/js/h5p-resizer.js" charset="UTF-8"></script>',
            'url' => $embedUrl,
            'title' => $content['title'],
            'displayOptions' => $core->getDisplayOptionsForView($content['disable'], $author_id),
            'metadata' => $content['metadata'],
            'contentUserData' => [
                0 => [
                    'state' => '{}',
                ],
            ],
        ];

        // Get preloaded user data for the current user

        if ($prefs['h5p_save_content_state'] === 'y' && $userId) {
            $results = json_decode(TikiLib::lib('user')->get_user_preference($user, "h5p_content_{$content['id']}"), true);

            if (! empty($results['preload'])) {
                    $settings['contentUserData'][$results['subContentId']][$results['dataType']] = json_encode($results['data']);
            }
        }

        return $settings;
    }

    /**
     * Add assets and JavaScript settings for the editor.
     *
     * @param int $id optional content identifier
     */
    public function addEditorAssets($id = null)
    {
        global $tikiroot, $tikipath, $prefs;

        // Add core assets
        $this->addCoreAssets();

        // Use jQuery and styles from core.
        $assets = [
            'css' => self::$settings['core']['styles'],
            'js' => self::$settings['core']['scripts']
        ];

        // Use relative URL to support both http and https.
        $editorpath = 'vendor_bundled/vendor/h5p/h5p-editor/';
        $url = $tikiroot . $editorpath;

        // Make sure files are reloaded for new versions
        $TWV = new TWVersion();
        $cachebuster = '?ver=' . $TWV->version;

        // Add editor styles
        foreach (H5peditor::$styles as $style) {
            $assets['css'][] = $url . $style . $cachebuster;
        }

        // Add editor JavaScript
        foreach (H5peditor::$scripts as $script) {
            // We do not want the creator of the iframe inside the iframe
            if ($script !== 'scripts/h5peditor-editor.js') {
                $assets['js'][] = $url . $script . $cachebuster;
            }
        }

        // Add JavaScript with library framework integration (editor part)
        TikiLib::lib('header')->add_jsfile($editorpath . 'scripts/h5peditor-editor.js');
        TikiLib::lib('header')->add_jsfile('lib/core/H5P/editor.js');

        // Add translation
        $languagescript = $editorpath . 'language/' . substr($prefs['language'], 0, 2) . '.js';
        if (! file_exists($tikipath . $languagescript)) {
            $languagescript = $editorpath . 'language/en.js';
        }
        TikiLib::lib('header')->add_jsfile($languagescript);

        // needs to be non-sefurl version so h5p can append the action and params
        $ajaxPath = 'tiki-ajax_services.php?controller=h5p&action=';

        // Add JavaScript settings
        $contentvalidator = \H5P_H5PTiki::get_h5p_instance('contentvalidator');
        self::$settings['editor'] = [
            'filesPath' => $tikiroot . \H5P_H5PTiki::$h5p_path . '/editor',
            'fileIcon' => [
                'path' => $url . 'images/binary-file.png',
                'width' => 50,
                'height' => 50,
            ],
            'ajaxPath' => $ajaxPath,
            'libraryUrl' => $url,
            'copyrightSemantics' => $contentvalidator->getCopyrightSemantics(),
            'metadataSemantics' => $contentvalidator->getMetadataSemantics(),
            'assets' => $assets,
            'apiVersion' => H5PCore::$coreApi,
        ];

        if ($id !== null) {
            self::$settings['editor']['nodeVersionId'] = $id;
        }

        $this->printSettings(self::$settings);
    }

    /**
     * Add assets and JavaScript settings for the editor.
     * @param array $content    H5P content
     * @param JitFilter $input
     * @return bool|int
     */
    public function saveContent(&$content, $input)
    {
        $core = \H5P_H5PTiki::get_h5p_instance('core');

        $oldLibrary = empty($content['library']) ? null : $content['library'];
        $oldParams = empty($content['params']) ? null : $content['params'];

        // Check parameters input
        $content['params'] = $input->parameters->xss();
        if (empty($content['params'])) {
            $core->h5pF->setErrorMessage(tr('Missing content parameters.'));
            return false;
        }

        // Decode parameters input
        $params = json_decode($content['params']);
        if ($params === null) {
            $core->h5pF->setErrorMessage(tr('Invalid content parameters.'));
            return false;
        }

        $content['params'] = json_encode($params->params);
        $content['metadata'] = json_encode($params->metadata);

        // Trim title and check length
        $content['title'] = $input->title->text();
        $trimmed_title = empty($content['title']) ? '' : trim($content['title']);
        if ($trimmed_title === '') {
            $core->h5pF->setErrorMessage(tr('Missing title.'));
            return false;
        }

        if (strlen($trimmed_title) > 255) {
            $core->h5pF->setErrorMessage(tr('Title is too long. Must be 256 letters or shorter.'));
            return false;
        }

        $content['title'] = $trimmed_title;

        // Get content type chosen in editor
        $content['library'] = $core->libraryFromString($input->library->text());
        if (! $content['library']) {
            $core->h5pF->setErrorMessage(tr('Invalid content type.'));
            return false;
        }

        // Check if content type exists
        $content['library']['libraryId'] = $core->h5pF->getLibraryId($content['library']['machineName'], $content['library']['majorVersion'], $content['library']['minorVersion']);
        if (! $content['library']['libraryId']) {
            $core->h5pF->setErrorMessage(tr("The chosen content type isn't installed."));
            return false;
        }

        // Set disabled features
        // TODO: Implement

        // create the file gallery file to attach this to
        global $prefs, $user;

        $fileId = $input->fileId->int();
        if (! $fileId) {
            // Prevent extracting and inserting the file we're creating
            $this->H5PTiki->isSaving = true;
            $file = new TikiFile([
                'galleryId' => $prefs['h5p_filegal_id'],
                'description' => tr('Created by H5P'),
                'user' => $user,
            ]);
            $fileId = $file->replace('', 'application/zip', $content['title'], TikiLib::remove_non_word_characters_and_accents($content['title']) . '.h5p');
            $this->H5PTiki->isSaving = false;
        }

        // Save new content
        $content['id'] = $core->saveContent($content, $fileId);

        // Move images to parmanent storage and find all required content dependencies
        $editor = \H5P_EditorTikiStorage::get_h5peditor_instance();
        $editor->processParameters($content['id'], $content['library'], $params->params, $oldLibrary, $oldParams);

        // export the project into the new file gallery file
        $content['file_id'] = $fileId;
        $core->filterParameters($content); // rebuild content

        // trigger the update event if not creating a new file
        if (empty($file)) {
            $file = TikiFile::id($fileId);
            TikiLib::events()->trigger(
                'tiki.file.update',
                [
                    'type'      => 'file',
                    'object'    => $fileId,
                    'user'      => $user,
                    'galleryId' => $file->galleryId,
                    'filetype'  => $file->filetype,
                ]
            );
        }

        return $fileId;
    }

    public function removeOldTmpFiles()
    {
        $older_than = time() - 86400;

      // Locate files
        $result = TikiDb::get()->query(
            'SELECT tf.`path` FROM `tiki_h5p_tmpfiles` tf WHERE tf.`created_at` < ?',
            $older_than
        );

        // Delete files from file system
        foreach ($result->result as $file) {
            @unlink($file['path']);
        }

        // Remove from tmpfiles table
        TikiDb::get()->query(
            'DELETE FROM `tiki_h5p_tmpfiles` WHERE `created_at` < ?',
            $older_than
        );
    }
}