Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\Core\Theme;
Chris@0: 
Chris@0: use Drupal\Core\Cache\CacheBackendInterface;
Chris@0: use Drupal\Core\Extension\Extension;
Chris@0: use Drupal\Core\Extension\ModuleHandlerInterface;
Chris@0: use Drupal\Core\Extension\ThemeHandlerInterface;
Chris@0: 
Chris@0: /**
Chris@0:  * Provides the theme initialization logic.
Chris@0:  */
Chris@0: class ThemeInitialization implements ThemeInitializationInterface {
Chris@0: 
Chris@0:   /**
Chris@0:    * The theme handler.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\Extension\ThemeHandlerInterface
Chris@0:    */
Chris@0:   protected $themeHandler;
Chris@0: 
Chris@0:   /**
Chris@0:    * The cache backend to use for the active theme.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\Cache\CacheBackendInterface
Chris@0:    */
Chris@0:   protected $cache;
Chris@0: 
Chris@0:   /**
Chris@0:    * The app root.
Chris@0:    *
Chris@0:    * @var string
Chris@0:    */
Chris@0:   protected $root;
Chris@0: 
Chris@0:   /**
Chris@0:    * The extensions that might be attaching assets.
Chris@0:    *
Chris@0:    * @var array
Chris@0:    */
Chris@0:   protected $extensions;
Chris@0: 
Chris@0:   /**
Chris@14:    * The module handler.
Chris@14:    *
Chris@14:    * @var \Drupal\Core\Extension\ModuleHandlerInterface
Chris@14:    */
Chris@14:   protected $moduleHandler;
Chris@14: 
Chris@14:   /**
Chris@0:    * Constructs a new ThemeInitialization object.
Chris@0:    *
Chris@0:    * @param string $root
Chris@0:    *   The app root.
Chris@0:    * @param \Drupal\Core\Extension\ThemeHandlerInterface $theme_handler
Chris@0:    *   The theme handler.
Chris@0:    * @param \Drupal\Core\Cache\CacheBackendInterface $cache
Chris@0:    *   The cache backend.
Chris@0:    * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
Chris@0:    *   The module handler to use to load modules.
Chris@0:    */
Chris@0:   public function __construct($root, ThemeHandlerInterface $theme_handler, CacheBackendInterface $cache, ModuleHandlerInterface $module_handler) {
Chris@0:     $this->root = $root;
Chris@0:     $this->themeHandler = $theme_handler;
Chris@0:     $this->cache = $cache;
Chris@0:     $this->moduleHandler = $module_handler;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function initTheme($theme_name) {
Chris@0:     $active_theme = $this->getActiveThemeByName($theme_name);
Chris@0:     $this->loadActiveTheme($active_theme);
Chris@0: 
Chris@0:     return $active_theme;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function getActiveThemeByName($theme_name) {
Chris@0:     if ($cached = $this->cache->get('theme.active_theme.' . $theme_name)) {
Chris@0:       return $cached->data;
Chris@0:     }
Chris@0:     $themes = $this->themeHandler->listInfo();
Chris@0: 
Chris@0:     // If no theme could be negotiated, or if the negotiated theme is not within
Chris@0:     // the list of installed themes, fall back to the default theme output of
Chris@0:     // core and modules (like Stark, but without a theme extension at all). This
Chris@0:     // is possible, because loadActiveTheme() always loads the Twig theme
Chris@0:     // engine. This is desired, because missing or malformed theme configuration
Chris@0:     // should not leave the application in a broken state. By falling back to
Chris@0:     // default output, the user is able to reconfigure the theme through the UI.
Chris@0:     // Lastly, tests are expected to operate with no theme by default, so as to
Chris@0:     // only assert the original theme output of modules (unless a test manually
Chris@0:     // installs a specific theme).
Chris@0:     if (empty($themes) || !$theme_name || !isset($themes[$theme_name])) {
Chris@0:       $theme_name = 'core';
Chris@0:       // /core/core.info.yml does not actually exist, but is required because
Chris@0:       // Extension expects a pathname.
Chris@0:       $active_theme = $this->getActiveTheme(new Extension($this->root, 'theme', 'core/core.info.yml'));
Chris@0: 
Chris@0:       // Early-return and do not set state, because the initialized $theme_name
Chris@0:       // differs from the original $theme_name.
Chris@0:       return $active_theme;
Chris@0:     }
Chris@0: 
Chris@0:     // Find all our ancestor themes and put them in an array.
Chris@0:     $base_themes = [];
Chris@0:     $ancestor = $theme_name;
Chris@0:     while ($ancestor && isset($themes[$ancestor]->base_theme)) {
Chris@0:       $ancestor = $themes[$ancestor]->base_theme;
Chris@0:       if (!$this->themeHandler->themeExists($ancestor)) {
Chris@0:         if ($ancestor == 'stable') {
Chris@0:           // Themes that depend on Stable will be fixed by system_update_8014().
Chris@0:           // There is no harm in not adding it as an ancestor since at worst
Chris@0:           // some people might experience slight visual regressions on
Chris@0:           // update.php.
Chris@0:           continue;
Chris@0:         }
Chris@0:         throw new MissingThemeDependencyException(sprintf('Base theme %s has not been installed.', $ancestor), $ancestor);
Chris@0:       }
Chris@0:       $base_themes[] = $themes[$ancestor];
Chris@0:     }
Chris@0: 
Chris@0:     $active_theme = $this->getActiveTheme($themes[$theme_name], $base_themes);
Chris@0: 
Chris@0:     $this->cache->set('theme.active_theme.' . $theme_name, $active_theme);
Chris@0:     return $active_theme;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function loadActiveTheme(ActiveTheme $active_theme) {
Chris@0:     // Initialize the theme.
Chris@0:     if ($theme_engine = $active_theme->getEngine()) {
Chris@0:       // Include the engine.
Chris@0:       include_once $this->root . '/' . $active_theme->getOwner();
Chris@0: 
Chris@0:       if (function_exists($theme_engine . '_init')) {
Chris@18:         foreach ($active_theme->getBaseThemeExtensions() as $base) {
Chris@18:           call_user_func($theme_engine . '_init', $base);
Chris@0:         }
Chris@0:         call_user_func($theme_engine . '_init', $active_theme->getExtension());
Chris@0:       }
Chris@0:     }
Chris@0:     else {
Chris@0:       // include non-engine theme files
Chris@18:       foreach ($active_theme->getBaseThemeExtensions() as $base) {
Chris@0:         // Include the theme file or the engine.
Chris@18:         if ($base->owner) {
Chris@18:           include_once $this->root . '/' . $base->owner;
Chris@0:         }
Chris@0:       }
Chris@0:       // and our theme gets one too.
Chris@0:       if ($active_theme->getOwner()) {
Chris@0:         include_once $this->root . '/' . $active_theme->getOwner();
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     // Always include Twig as the default theme engine.
Chris@0:     include_once $this->root . '/core/themes/engines/twig/twig.engine';
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function getActiveTheme(Extension $theme, array $base_themes = []) {
Chris@0:     $theme_path = $theme->getPath();
Chris@0: 
Chris@0:     $values['path'] = $theme_path;
Chris@0:     $values['name'] = $theme->getName();
Chris@0: 
Chris@17:     // Use the logo declared in this themes info file, otherwise use logo.svg
Chris@17:     // from the themes root.
Chris@17:     if (!empty($theme->info['logo'])) {
Chris@17:       $values['logo'] = $theme->getPath() . '/' . $theme->info['logo'];
Chris@17:     }
Chris@17:     else {
Chris@17:       $values['logo'] = $theme->getPath() . '/logo.svg';
Chris@17:     }
Chris@17: 
Chris@0:     // @todo Remove in Drupal 9.0.x.
Chris@0:     $values['stylesheets_remove'] = $this->prepareStylesheetsRemove($theme, $base_themes);
Chris@0: 
Chris@0:     // Prepare libraries overrides from this theme and ancestor themes. This
Chris@0:     // allows child themes to easily remove CSS files from base themes and
Chris@0:     // modules.
Chris@0:     $values['libraries_override'] = [];
Chris@0: 
Chris@0:     // Get libraries overrides declared by base themes.
Chris@0:     foreach ($base_themes as $base) {
Chris@0:       if (!empty($base->info['libraries-override'])) {
Chris@0:         foreach ($base->info['libraries-override'] as $library => $override) {
Chris@0:           $values['libraries_override'][$base->getPath()][$library] = $override;
Chris@0:         }
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     // Add libraries overrides declared by this theme.
Chris@0:     if (!empty($theme->info['libraries-override'])) {
Chris@0:       foreach ($theme->info['libraries-override'] as $library => $override) {
Chris@0:         $values['libraries_override'][$theme->getPath()][$library] = $override;
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     // Get libraries extensions declared by base themes.
Chris@0:     foreach ($base_themes as $base) {
Chris@0:       if (!empty($base->info['libraries-extend'])) {
Chris@0:         foreach ($base->info['libraries-extend'] as $library => $extend) {
Chris@0:           if (isset($values['libraries_extend'][$library])) {
Chris@0:             // Merge if libraries-extend has already been defined for this
Chris@0:             // library.
Chris@0:             $values['libraries_extend'][$library] = array_merge($values['libraries_extend'][$library], $extend);
Chris@0:           }
Chris@0:           else {
Chris@0:             $values['libraries_extend'][$library] = $extend;
Chris@0:           }
Chris@0:         }
Chris@0:       }
Chris@0:     }
Chris@0:     // Add libraries extensions declared by this theme.
Chris@0:     if (!empty($theme->info['libraries-extend'])) {
Chris@0:       foreach ($theme->info['libraries-extend'] as $library => $extend) {
Chris@0:         if (isset($values['libraries_extend'][$library])) {
Chris@0:           // Merge if libraries-extend has already been defined for this
Chris@0:           // library.
Chris@0:           $values['libraries_extend'][$library] = array_merge($values['libraries_extend'][$library], $extend);
Chris@0:         }
Chris@0:         else {
Chris@0:           $values['libraries_extend'][$library] = $extend;
Chris@0:         }
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     // Do basically the same as the above for libraries
Chris@0:     $values['libraries'] = [];
Chris@0: 
Chris@0:     // Grab libraries from base theme
Chris@0:     foreach ($base_themes as $base) {
Chris@0:       if (!empty($base->libraries)) {
Chris@0:         foreach ($base->libraries as $library) {
Chris@0:           $values['libraries'][] = $library;
Chris@0:         }
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     // Add libraries used by this theme.
Chris@0:     if (!empty($theme->libraries)) {
Chris@0:       foreach ($theme->libraries as $library) {
Chris@0:         $values['libraries'][] = $library;
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     $values['engine'] = isset($theme->engine) ? $theme->engine : NULL;
Chris@0:     $values['owner'] = isset($theme->owner) ? $theme->owner : NULL;
Chris@0:     $values['extension'] = $theme;
Chris@0: 
Chris@0:     $base_active_themes = [];
Chris@0:     foreach ($base_themes as $base_theme) {
Chris@18:       $base_active_themes[$base_theme->getName()] = $base_theme;
Chris@0:     }
Chris@0: 
Chris@18:     $values['base_theme_extensions'] = $base_active_themes;
Chris@0:     if (!empty($theme->info['regions'])) {
Chris@0:       $values['regions'] = $theme->info['regions'];
Chris@0:     }
Chris@0: 
Chris@0:     return new ActiveTheme($values);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Gets all extensions.
Chris@0:    *
Chris@0:    * @return array
Chris@0:    */
Chris@0:   protected function getExtensions() {
Chris@0:     if (!isset($this->extensions)) {
Chris@0:       $this->extensions = array_merge($this->moduleHandler->getModuleList(), $this->themeHandler->listInfo());
Chris@0:     }
Chris@0:     return $this->extensions;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Gets CSS file where tokens have been resolved.
Chris@0:    *
Chris@0:    * @param string $css_file
Chris@0:    *   CSS file which may contain tokens.
Chris@0:    *
Chris@0:    * @return string
Chris@0:    *   CSS file where placeholders are replaced.
Chris@0:    *
Chris@0:    * @todo Remove in Drupal 9.0.x.
Chris@0:    */
Chris@0:   protected function resolveStyleSheetPlaceholders($css_file) {
Chris@0:     $token_candidate = explode('/', $css_file)[0];
Chris@0:     if (!preg_match('/@[A-z0-9_-]+/', $token_candidate)) {
Chris@0:       return $css_file;
Chris@0:     }
Chris@0: 
Chris@0:     $token = substr($token_candidate, 1);
Chris@0: 
Chris@0:     // Prime extensions.
Chris@0:     $extensions = $this->getExtensions();
Chris@0:     if (isset($extensions[$token])) {
Chris@0:       return str_replace($token_candidate, $extensions[$token]->getPath(), $css_file);
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Prepares stylesheets-remove specified in the *.info.yml file.
Chris@0:    *
Chris@0:    * @param \Drupal\Core\Extension\Extension $theme
Chris@0:    *   The theme extension object.
Chris@0:    * @param \Drupal\Core\Extension\Extension[] $base_themes
Chris@0:    *   An array of base themes.
Chris@0:    *
Chris@0:    * @return string[]
Chris@0:    *   The list of stylesheets-remove specified in the *.info.yml file.
Chris@0:    *
Chris@0:    * @todo Remove in Drupal 9.0.x.
Chris@0:    */
Chris@0:   protected function prepareStylesheetsRemove(Extension $theme, $base_themes) {
Chris@0:     // Prepare stylesheets from this theme as well as all ancestor themes.
Chris@0:     // We work it this way so that we can have child themes remove CSS files
Chris@0:     // easily from parent.
Chris@0:     $stylesheets_remove = [];
Chris@0:     // Grab stylesheets from base theme.
Chris@0:     foreach ($base_themes as $base) {
Chris@0:       if (!empty($base->info['stylesheets-remove'])) {
Chris@0:         foreach ($base->info['stylesheets-remove'] as $css_file) {
Chris@0:           $css_file = $this->resolveStyleSheetPlaceholders($css_file);
Chris@0:           $stylesheets_remove[$css_file] = $css_file;
Chris@0:         }
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     // Add stylesheets used by this theme.
Chris@0:     if (!empty($theme->info['stylesheets-remove'])) {
Chris@0:       foreach ($theme->info['stylesheets-remove'] as $css_file) {
Chris@0:         $css_file = $this->resolveStyleSheetPlaceholders($css_file);
Chris@0:         $stylesheets_remove[$css_file] = $css_file;
Chris@0:       }
Chris@0:     }
Chris@0:     return $stylesheets_remove;
Chris@0:   }
Chris@0: 
Chris@0: }