--- /dev/null
+<?php
+
+namespace Drupal\Core\EventSubscriber;
+
+use Drupal\Component\Serialization\Json;
+use Drupal\Core\Language\LanguageInterface;
+use Drupal\Core\Language\LanguageManagerInterface;
+use Drupal\Core\Path\CurrentPathStack;
+use Drupal\Core\Path\PathMatcherInterface;
+use Drupal\Core\Session\AccountInterface;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+use Symfony\Component\HttpKernel\Event\FilterResponseEvent;
+use Symfony\Component\HttpKernel\KernelEvents;
+
+/**
+ * Subscribes to filter HTML responses, to set the 'is-active' class on links.
+ *
+ * Only for anonymous users; for authenticated users, the active-link asset
+ * library is loaded.
+ *
+ * @see system_page_attachments()
+ */
+class ActiveLinkResponseFilter implements EventSubscriberInterface {
+
+ /**
+ * The current user.
+ *
+ * @var \Drupal\Core\Session\AccountInterface
+ */
+ protected $currentUser;
+
+ /**
+ * The current path.
+ *
+ * @var \Drupal\Core\Path\CurrentPathStack
+ */
+ protected $currentPath;
+
+ /**
+ * The path matcher.
+ *
+ * @var \Drupal\Core\Path\PathMatcherInterface
+ */
+ protected $pathMatcher;
+
+ /**
+ * The language manager.
+ *
+ * @var \Drupal\Core\Language\LanguageManagerInterface
+ */
+ protected $languageManager;
+
+ /**
+ * Constructs a new ActiveLinkResponseFilter instance.
+ *
+ * @param \Drupal\Core\Session\AccountInterface $current_user
+ * The current user.
+ * @param \Drupal\Core\Path\CurrentPathStack $current_path
+ * The current path.
+ * @param \Drupal\Core\Path\PathMatcherInterface $path_matcher
+ * The path matcher.
+ * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
+ * The language manager.
+ */
+ public function __construct(AccountInterface $current_user, CurrentPathStack $current_path, PathMatcherInterface $path_matcher, LanguageManagerInterface $language_manager) {
+ $this->currentUser = $current_user;
+ $this->currentPath = $current_path;
+ $this->pathMatcher = $path_matcher;
+ $this->languageManager = $language_manager;
+ }
+
+ /**
+ * Sets the 'is-active' class on links.
+ *
+ * @param \Symfony\Component\HttpKernel\Event\FilterResponseEvent $event
+ * The response event.
+ */
+ public function onResponse(FilterResponseEvent $event) {
+ // Only care about HTML responses.
+ if (stripos($event->getResponse()->headers->get('Content-Type'), 'text/html') === FALSE) {
+ return;
+ }
+
+ // For authenticated users, the 'is-active' class is set in JavaScript.
+ // @see system_page_attachments()
+ if ($this->currentUser->isAuthenticated()) {
+ return;
+ }
+
+ $response = $event->getResponse();
+ $response->setContent(static::setLinkActiveClass(
+ $response->getContent(),
+ ltrim($this->currentPath->getPath(), '/'),
+ $this->pathMatcher->isFrontPage(),
+ $this->languageManager->getCurrentLanguage(LanguageInterface::TYPE_URL)->getId(),
+ $event->getRequest()->query->all()
+ ));
+ }
+
+
+ /**
+ * Sets the "is-active" class on relevant links.
+ *
+ * This is a PHP implementation of the drupal.active-link JavaScript library.
+ *
+ * @param string $html_markup
+ * The HTML markup to update.
+ * @param string $current_path
+ * The system path of the currently active page.
+ * @param bool $is_front
+ * Whether the current page is the front page (which implies the current
+ * path might also be <front>).
+ * @param string $url_language
+ * The language code of the current URL.
+ * @param array $query
+ * The query string for the current URL.
+ *
+ * @return string
+ * The updated HTML markup.
+ *
+ * @todo Once a future version of PHP supports parsing HTML5 properly
+ * (i.e. doesn't fail on
+ * https://www.drupal.org/comment/7938201#comment-7938201) then we can get
+ * rid of this manual parsing and use DOMDocument instead.
+ */
+ public static function setLinkActiveClass($html_markup, $current_path, $is_front, $url_language, array $query) {
+ $search_key_current_path = 'data-drupal-link-system-path="' . $current_path . '"';
+ $search_key_front = 'data-drupal-link-system-path="<front>"';
+
+ $offset = 0;
+ // There are two distinct conditions that can make a link be marked active:
+ // 1. A link has the current path in its 'data-drupal-link-system-path'
+ // attribute.
+ // 2. We are on the front page and a link has the special '<front>' value in
+ // its 'data-drupal-link-system-path' attribute.
+ while (strpos($html_markup, $search_key_current_path, $offset) !== FALSE || ($is_front && strpos($html_markup, $search_key_front, $offset) !== FALSE)) {
+ $pos_current_path = strpos($html_markup, $search_key_current_path, $offset);
+ // Only look for links with the special '<front>' system path if we are
+ // actually on the front page.
+ $pos_front = $is_front ? strpos($html_markup, $search_key_front, $offset) : FALSE;
+
+ // Determine which of the two values is the next match: the exact path, or
+ // the <front> special case.
+ $pos_match = NULL;
+ if ($pos_front === FALSE) {
+ $pos_match = $pos_current_path;
+ }
+ elseif ($pos_current_path === FALSE) {
+ $pos_match = $pos_front;
+ }
+ elseif ($pos_current_path < $pos_front) {
+ $pos_match = $pos_current_path;
+ }
+ else {
+ $pos_match = $pos_front;
+ }
+
+ // Find beginning and ending of opening tag.
+ $pos_tag_start = NULL;
+ for ($i = $pos_match; $pos_tag_start === NULL && $i > 0; $i--) {
+ if ($html_markup[$i] === '<') {
+ $pos_tag_start = $i;
+ }
+ }
+ $pos_tag_end = NULL;
+ for ($i = $pos_match; $pos_tag_end === NULL && $i < strlen($html_markup); $i++) {
+ if ($html_markup[$i] === '>') {
+ $pos_tag_end = $i;
+ }
+ }
+
+ // Get the HTML: this will be the opening part of a single tag, e.g.:
+ // <a href="/" data-drupal-link-system-path="<front>">
+ $tag = substr($html_markup, $pos_tag_start, $pos_tag_end - $pos_tag_start + 1);
+
+ // Parse it into a DOMDocument so we can reliably read and modify
+ // attributes.
+ $dom = new \DOMDocument();
+ @$dom->loadHTML('<!DOCTYPE html><html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /></head><body>' . $tag . '</body></html>');
+ $node = $dom->getElementsByTagName('body')->item(0)->firstChild;
+
+ // Ensure we don't set the "active" class twice on the same element.
+ $class = $node->getAttribute('class');
+ $add_active = !in_array('is-active', explode(' ', $class));
+
+ // The language of an active link is equal to the current language.
+ if ($add_active && $url_language) {
+ if ($node->hasAttribute('hreflang') && $node->getAttribute('hreflang') !== $url_language) {
+ $add_active = FALSE;
+ }
+ }
+ // The query parameters of an active link are equal to the current
+ // parameters.
+ if ($add_active) {
+ if ($query) {
+ if (!$node->hasAttribute('data-drupal-link-query') || $node->getAttribute('data-drupal-link-query') !== Json::encode($query)) {
+ $add_active = FALSE;
+ }
+ }
+ else {
+ if ($node->hasAttribute('data-drupal-link-query')) {
+ $add_active = FALSE;
+ }
+ }
+ }
+
+ // Only if the path, the language and the query match, we set the
+ // "is-active" class.
+ if ($add_active) {
+ if (strlen($class) > 0) {
+ $class .= ' ';
+ }
+ $class .= 'is-active';
+ $node->setAttribute('class', $class);
+
+ // Get the updated tag.
+ $updated_tag = $dom->saveXML($node, LIBXML_NOEMPTYTAG);
+ // saveXML() added a closing tag, remove it.
+ $updated_tag = substr($updated_tag, 0, strrpos($updated_tag, '<'));
+
+ $html_markup = str_replace($tag, $updated_tag, $html_markup);
+
+ // Ensure we only search the remaining HTML.
+ $offset = $pos_tag_end - strlen($tag) + strlen($updated_tag);
+ }
+ else {
+ // Ensure we only search the remaining HTML.
+ $offset = $pos_tag_end + 1;
+ }
+ }
+
+ return $html_markup;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public static function getSubscribedEvents() {
+ // Should run after any other response subscriber that modifies the markup.
+ $events[KernelEvents::RESPONSE][] = ['onResponse', -512];
+
+ return $events;
+ }
+
+}
projects / yaffs-website / blobdiff