class SystemTokensHooks

class SystemTokensHooks {
    
    /**
     * Implements hook_token_info().
     */
    public function tokenInfo() {
        $types['site'] = [
            'name' => t("Site information"),
            'description' => t("Tokens for site-wide settings and other global information."),
        ];
        $types['date'] = [
            'name' => t("Dates"),
            'description' => t("Tokens related to times and dates."),
        ];
        // Site-wide global tokens.
        $site['name'] = [
            'name' => t("Name"),
            'description' => t("The name of the site."),
        ];
        $site['slogan'] = [
            'name' => t("Slogan"),
            'description' => t("The slogan of the site."),
        ];
        $site['mail'] = [
            'name' => t("Email"),
            'description' => t("The administrative email address for the site."),
        ];
        $site['base-url'] = [
            'name' => t("Base URL"),
            'description' => t("The base URL of the site, currently: @base_url", [
                '@base_url' => \Drupal::service('router.request_context')->getCompleteBaseUrl(),
            ]),
        ];
        $site['base-path'] = [
            'name' => t("Base path"),
            'description' => t("The base path of the site, currently: @base_path", [
                '@base_path' => \Drupal::request()->getBasePath(),
            ]),
        ];
        $site['url'] = [
            'name' => t("URL"),
            'description' => t("The URL of the site's front page with the language prefix, if it exists."),
        ];
        $site['url-brief'] = [
            'name' => t("URL (brief)"),
            'description' => t("The URL of the site's front page without the protocol."),
        ];
        $site['login-url'] = [
            'name' => t("Login page"),
            'description' => t("The URL of the site's login page."),
        ];
        
        /** @var \Drupal\Core\Datetime\DateFormatterInterface $date_formatter */
        $date_formatter = \Drupal::service('date.formatter');
        // Date related tokens.
        $request_time = \Drupal::time()->getRequestTime();
        $date['short'] = [
            'name' => t("Short format"),
            'description' => t("The current date in 'short' format. (%date)", [
                '%date' => $date_formatter->format($request_time, 'short'),
            ]),
        ];
        $date['medium'] = [
            'name' => t("Medium format"),
            'description' => t("The current date in 'medium' format. (%date)", [
                '%date' => $date_formatter->format($request_time, 'medium'),
            ]),
        ];
        $date['long'] = [
            'name' => t("Long format"),
            'description' => t("The current date in 'long' format. (%date)", [
                '%date' => $date_formatter->format($request_time, 'long'),
            ]),
        ];
        $date['custom'] = [
            'name' => t("Custom format"),
            'description' => t('The current date in a custom format. See <a href="https://www.php.net/manual/datetime.format.php#refsect1-datetime.format-parameters">the PHP documentation</a> for details.'),
        ];
        $date['since'] = [
            'name' => t("Time-since"),
            'description' => t("The current date in 'time-since' format. (%date)", [
                '%date' => $date_formatter->formatTimeDiffSince($request_time - 360),
            ]),
        ];
        $date['raw'] = [
            'name' => t("Raw timestamp"),
            'description' => t("The current date in UNIX timestamp format (%date)", [
                '%date' => $request_time,
            ]),
        ];
        return [
            'types' => $types,
            'tokens' => [
                'site' => $site,
                'date' => $date,
            ],
        ];
    }
    
    /**
     * Implements hook_tokens().
     */
    public function tokens($type, $tokens, array $data, array $options, BubbleableMetadata $bubbleable_metadata) {
        $token_service = \Drupal::token();
        $url_options = [
            'absolute' => TRUE,
        ];
        if (isset($options['langcode'])) {
            $url_options['language'] = \Drupal::languageManager()->getLanguage($options['langcode']);
            $langcode = $options['langcode'];
        }
        else {
            $langcode = NULL;
        }
        $replacements = [];
        if ($type == 'site') {
            foreach ($tokens as $name => $original) {
                switch ($name) {
                    case 'name':
                        $config = \Drupal::config('system.site');
                        $bubbleable_metadata->addCacheableDependency($config);
                        $site_name = $config->get('name');
                        $replacements[$original] = $site_name;
                        break;
                    case 'slogan':
                        $config = \Drupal::config('system.site');
                        $bubbleable_metadata->addCacheableDependency($config);
                        $slogan = $config->get('slogan');
                        $build = [
                            '#markup' => $slogan,
                        ];
                        // @todo Fix in https://www.drupal.org/node/2577827
                        $replacements[$original] = \Drupal::service('renderer')->renderInIsolation($build);
                        break;
                    case 'mail':
                        $config = \Drupal::config('system.site');
                        $bubbleable_metadata->addCacheableDependency($config);
                        $replacements[$original] = $config->get('mail');
                        break;
                    case 'base-url':
                        $bubbleable_metadata->addCacheContexts([
                            'url.site',
                        ]);
                        $replacements[$original] = \Drupal::service('router.request_context')->getCompleteBaseUrl();
                        break;
                    case 'base-path':
                        $bubbleable_metadata->addCacheContexts([
                            'url.site',
                        ]);
                        $replacements[$original] = \Drupal::request()->getBasePath();
                        break;
                    case 'url':
                        
                        /** @var \Drupal\Core\GeneratedUrl $result */
                        $result = Url::fromRoute('<front>', [], $url_options)->toString(TRUE);
                        $bubbleable_metadata->addCacheableDependency($result);
                        $replacements[$original] = $result->getGeneratedUrl();
                        break;
                    case 'url-brief':
                        
                        /** @var \Drupal\Core\GeneratedUrl $result */
                        $result = Url::fromRoute('<front>', [], $url_options)->toString(TRUE);
                        $bubbleable_metadata->addCacheableDependency($result);
                        $replacements[$original] = preg_replace([
                            '!^https?://!',
                            '!/$!',
                        ], '', $result->getGeneratedUrl());
                        break;
                    case 'login-url':
                        
                        /** @var \Drupal\Core\GeneratedUrl $result */
                        $result = Url::fromRoute('user.page', [], $url_options)->toString(TRUE);
                        $bubbleable_metadata->addCacheableDependency($result);
                        $replacements[$original] = $result->getGeneratedUrl();
                        break;
                }
            }
        }
        elseif ($type == 'date') {
            if (empty($data['date'])) {
                $date = \Drupal::time()->getRequestTime();
                // We depend on the current request time, so the tokens are not cacheable
                // at all.
                $bubbleable_metadata->setCacheMaxAge(0);
            }
            else {
                $date = $data['date'];
            }
            foreach ($tokens as $name => $original) {
                switch ($name) {
                    case 'short':
                    case 'medium':
                    case 'long':
                        $date_format = DateFormat::load($name);
                        $bubbleable_metadata->addCacheableDependency($date_format);
                        $replacements[$original] = \Drupal::service('date.formatter')->format($date, $name, '', NULL, $langcode);
                        break;
                    case 'since':
                        $replacements[$original] = \Drupal::service('date.formatter')->formatTimeDiffSince($date, [
                            'langcode' => $langcode,
                        ]);
                        $bubbleable_metadata->setCacheMaxAge(0);
                        break;
                    case 'raw':
                        $replacements[$original] = $date;
                        break;
                }
            }
            if ($created_tokens = $token_service->findWithPrefix($tokens, 'custom')) {
                foreach ($created_tokens as $name => $original) {
                    $replacements[$original] = \Drupal::service('date.formatter')->format($date, 'custom', $name, NULL, $langcode);
                }
            }
        }
        return $replacements;
    }

}