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41 results

theme.inc

  • webchick's avatar
    Issue #1687864 by sun, BarisW, mgifford, sebsebseb123: Bring theme_breadcrumb() up to WCAG 2.0 AA.
    Angie Byron authored
    e8a88530
    History
    Code owners
    Assign users and groups as approvers for specific file changes. Learn more.
    theme.inc 117.68 KiB
    <?php
    
    /**
     * @file
     * The theme system, which controls the output of Drupal.
     *
     * The theme system allows for nearly all output of the Drupal system to be
     * customized by user themes.
     */
    
    use Drupal\Core\Cache\CacheBackendInterface;
    use Drupal\Core\Template\Attribute;
    use Drupal\Core\Utility\ThemeRegistry;
    
    /**
     * @defgroup content_flags Content markers
     * @{
     * Markers used by theme_mark() and node_mark() to designate content.
     * @see theme_mark(), node_mark()
     */
    
    /**
     * Mark content as read.
     */
    const MARK_READ = 0;
    
    /**
     * Mark content as being new.
     */
    const MARK_NEW = 1;
    
    /**
     * Mark content as being updated.
     */
    const MARK_UPDATED = 2;
    
    /**
     * A responsive table class; hide table cell on narrow devices.
     *
     * Indicates that a column has medium priority and thus can be hidden on narrow
     * width devices and shown on medium+ width devices (i.e. tablets and desktops).
     */
    const RESPONSIVE_PRIORITY_MEDIUM = 'priority-medium';
    
    /**
     * A responsive table class; only show table cell on wide devices.
     *
     * Indicates that a column has low priority and thus can be hidden on narrow
     * and medium viewports and shown on wide devices (i.e. desktops).
     */
    const RESPONSIVE_PRIORITY_LOW = 'priority-low';
    
    /**
     * @} End of "defgroup content_flags".
     */
    
    /**
     * Determines if a theme is available to use.
     *
     * @param $theme
     *   Either the name of a theme or a full theme object.
     *
     * @return
     *   Boolean TRUE if the theme is enabled or is the site administration theme;
     *   FALSE otherwise.
     */
    function drupal_theme_access($theme) {
      if (is_object($theme)) {
        return !empty($theme->status);
      }
      else {
        $themes = list_themes();
        return !empty($themes[$theme]->status);
      }
    }
    
    /**
     * Initialize the theme system by loading the theme.
     */
    function drupal_theme_initialize() {
      global $theme, $user, $theme_key;
    
      // If $theme is already set, assume the others are set, too, and do nothing
      if (isset($theme)) {
        return;
      }
    
      drupal_bootstrap(DRUPAL_BOOTSTRAP_DATABASE);
      $themes = list_themes();
    
      // Only select the user selected theme if it is available in the
      // list of themes that can be accessed.
      $theme = !empty($user->theme) && drupal_theme_access($user->theme) ? $user->theme : variable_get('theme_default', 'stark');
    
      // Allow modules to override the theme. Validation has already been performed
      // inside menu_get_custom_theme(), so we do not need to check it again here.
      $custom_theme = menu_get_custom_theme();
      $theme = !empty($custom_theme) ? $custom_theme : $theme;
    
      // Store the identifier for retrieving theme settings with.
      $theme_key = $theme;
    
      // Find all our ancestor themes and put them in an array.
      $base_theme = array();
      $ancestor = $theme;
      while ($ancestor && isset($themes[$ancestor]->base_theme)) {
        $ancestor = $themes[$ancestor]->base_theme;
        $base_theme[] = $themes[$ancestor];
      }
      _drupal_theme_initialize($themes[$theme], array_reverse($base_theme));
    
      // Themes can have alter functions, so reset the drupal_alter() cache.
      drupal_static_reset('drupal_alter');
    }
    
    /**
     * Initialize the theme system given already loaded information. This
     * function is useful to initialize a theme when no database is present.
     *
     * @param $theme
     *   An object with the following information:
     *     filename
     *       The .info file for this theme. The 'path' to
     *       the theme will be in this file's directory. (Required)
     *     owner
     *       The path to the .theme file or the .engine file to load for
     *       the theme. (Required)
     *     stylesheet
     *       The primary stylesheet for the theme. (Optional)
     *     engine
     *       The name of theme engine to use. (Optional)
     * @param $base_theme
     *    An optional array of objects that represent the 'base theme' if the
     *    theme is meant to be derivative of another theme. It requires
     *    the same information as the $theme object. It should be in
     *    'oldest first' order, meaning the top level of the chain will
     *    be first.
     * @param $registry_callback
     *   The callback to invoke to set the theme registry.
     */
    function _drupal_theme_initialize($theme, $base_theme = array(), $registry_callback = '_theme_load_registry') {
      global $theme_info, $base_theme_info, $theme_engine, $theme_path;
      $theme_info = $theme;
      $base_theme_info = $base_theme;
    
      $theme_path = dirname($theme->filename);
    
      // Prepare stylesheets from this theme as well as all ancestor themes.
      // We work it this way so that we can have child themes override parent
      // theme stylesheets easily.
      $final_stylesheets = array();
    
      // Grab stylesheets from base theme
      foreach ($base_theme as $base) {
        if (!empty($base->stylesheets)) {
          foreach ($base->stylesheets as $media => $stylesheets) {
            foreach ($stylesheets as $name => $stylesheet) {
              $final_stylesheets[$media][$name] = $stylesheet;
            }
          }
        }
      }
    
      // Add stylesheets used by this theme.
      if (!empty($theme->stylesheets)) {
        foreach ($theme->stylesheets as $media => $stylesheets) {
          foreach ($stylesheets as $name => $stylesheet) {
            $final_stylesheets[$media][$name] = $stylesheet;
          }
        }
      }
    
      // And now add the stylesheets properly
      foreach ($final_stylesheets as $media => $stylesheets) {
        foreach ($stylesheets as $stylesheet) {
          drupal_add_css($stylesheet, array('group' => CSS_THEME, 'every_page' => TRUE, 'media' => $media));
        }
      }
    
      // Do basically the same as the above for scripts
      $final_scripts = array();
    
      // Grab scripts from base theme
      foreach ($base_theme as $base) {
        if (!empty($base->scripts)) {
          foreach ($base->scripts as $name => $script) {
            $final_scripts[$name] = $script;
          }
        }
      }
    
      // Add scripts used by this theme.
      if (!empty($theme->scripts)) {
        foreach ($theme->scripts as $name => $script) {
          $final_scripts[$name] = $script;
        }
      }
    
      // Add scripts used by this theme.
      foreach ($final_scripts as $script) {
        drupal_add_js($script, array('group' => JS_THEME, 'every_page' => TRUE));
      }
    
      $theme_engine = NULL;
    
      // Initialize the theme.
      if (isset($theme->engine)) {
        // Include the engine.
        include_once DRUPAL_ROOT . '/' . $theme->owner;
    
        $theme_engine = $theme->engine;
        if (function_exists($theme_engine . '_init')) {
          foreach ($base_theme as $base) {
            call_user_func($theme_engine . '_init', $base);
          }
          call_user_func($theme_engine . '_init', $theme);
        }
      }
      else {
        // include non-engine theme files
        foreach ($base_theme as $base) {
          // Include the theme file or the engine.
          if (!empty($base->owner)) {
            include_once DRUPAL_ROOT . '/' . $base->owner;
          }
        }
        // and our theme gets one too.
        if (!empty($theme->owner)) {
          include_once DRUPAL_ROOT . '/' . $theme->owner;
        }
      }
      // Load twig as secondary always available engine.
      // @todo Make twig the default engine and remove this. This is required
      // because (by design) the theme system doesn't allow modules to register more
      // than one type of extension. We need a temporary backwards compatibility
      // layer to allow us to perform core-wide .tpl.php to .twig conversion.
      include_once DRUPAL_ROOT . '/core/themes/engines/twig/twig.engine';
    
      if (isset($registry_callback)) {
        _theme_registry_callback($registry_callback, array($theme, $base_theme, $theme_engine));
      }
    }
    
    /**
     * Get the theme registry.
     *
     * @param bool $complete
     *   Optional boolean to indicate whether to return the complete theme registry
     *   array or an instance of the Drupal\Core\Utility\ThemeRegistry class.
     *   If TRUE, the complete theme registry array will be returned. This is useful
     *   if you want to foreach over the whole registry, use array_* functions or
     *   inspect it in a debugger. If FALSE, an instance of the
     *   Drupal\Core\Utility\ThemeRegistry class will be returned, this provides an
     *   ArrayObject which allows it to be accessed with array syntax and isset(),
     *   and should be more lightweight than the full registry. Defaults to TRUE.
     *
     * @return
     *   The complete theme registry array, or an instance of the
     *   Drupal\Core\Utility\ThemeRegistry class.
     */
    function theme_get_registry($complete = TRUE) {
      // Use the advanced drupal_static() pattern, since this is called very often.
      static $drupal_static_fast;
      if (!isset($drupal_static_fast)) {
        $drupal_static_fast['registry'] = &drupal_static('theme_get_registry');
      }
      $theme_registry = &$drupal_static_fast['registry'];
    
      // Initialize the theme, if this is called early in the bootstrap, or after
      // static variables have been reset.
      if (!is_array($theme_registry)) {
        drupal_theme_initialize();
        $theme_registry = array();
      }
    
      $key = (int) $complete;
    
      if (!isset($theme_registry[$key])) {
        list($callback, $arguments) = _theme_registry_callback();
        if (!$complete) {
          $arguments[] = FALSE;
        }
        $theme_registry[$key] = call_user_func_array($callback, $arguments);
      }
    
      return $theme_registry[$key];
    }
    
    /**
     * Set the callback that will be used by theme_get_registry() to fetch the registry.
     *
     * @param $callback
     *   The name of the callback function.
     * @param $arguments
     *   The arguments to pass to the function.
     */
    function _theme_registry_callback($callback = NULL, array $arguments = array()) {
      static $stored;
      if (isset($callback)) {
        $stored = array($callback, $arguments);
      }
      return $stored;
    }
    
    /**
     * Get the theme_registry cache; if it doesn't exist, build it.
     *
     * @param $theme
     *   The loaded $theme object as returned by list_themes().
     * @param $base_theme
     *   An array of loaded $theme objects representing the ancestor themes in
     *   oldest first order.
     * @param $theme_engine
     *   The name of the theme engine.
     * @param $complete
     *   Whether to load the complete theme registry or an instance of the
     *   Drupal\Core\Utility\ThemeRegistry class.
     *
     * @return
     *   The theme registry array, or an instance of the
     *   Drupal\Core\Utility\ThemeRegistry class.
     */
    function _theme_load_registry($theme, $base_theme = NULL, $theme_engine = NULL, $complete = TRUE) {
      if ($complete) {
        // Check the theme registry cache; if it exists, use it.
        $cached = cache()->get("theme_registry:$theme->name");
        if (isset($cached->data)) {
          $registry = $cached->data;
        }
        else {
          // If not, build one and cache it.
          $registry = _theme_build_registry($theme, $base_theme, $theme_engine);
          // Only persist this registry if all modules are loaded. This assures a
          // complete set of theme hooks.
          if (module_load_all(NULL)) {
            _theme_save_registry($theme, $registry);
          }
        }
        return $registry;
      }
      else {
        return new ThemeRegistry('theme_registry:runtime:' . $theme->name, 'cache', array('theme_registry' => TRUE));
      }
    }
    
    /**
     * Write the theme_registry cache into the database.
     */
    function _theme_save_registry($theme, $registry) {
      cache()->set("theme_registry:$theme->name", $registry, CacheBackendInterface::CACHE_PERMANENT, array('theme_registry' => TRUE));
    }
    
    /**
     * Force the system to rebuild the theme registry; this should be called
     * when modules are added to the system, or when a dynamic system needs
     * to add more theme hooks.
     */
    function drupal_theme_rebuild() {
      drupal_static_reset('theme_get_registry');
      cache()->invalidateTags(array('theme_registry' => TRUE));
    }
    
    /**
     * Process a single implementation of hook_theme().
     *
     * @param $cache
     *   The theme registry that will eventually be cached; It is an associative
     *   array keyed by theme hooks, whose values are associative arrays describing
     *   the hook:
     *   - 'type': The passed-in $type.
     *   - 'theme path': The passed-in $path.
     *   - 'function': The name of the function generating output for this theme
     *     hook. Either defined explicitly in hook_theme() or, if neither 'function'
     *     nor 'template' is defined, then the default theme function name is used.
     *     The default theme function name is the theme hook prefixed by either
     *     'theme_' for modules or '$name_' for everything else. If 'function' is
     *     defined, 'template' is not used.
     *   - 'template': The filename of the template generating output for this
     *     theme hook. The template is in the directory defined by the 'path' key of
     *     hook_theme() or defaults to "$path/templates".
     *   - 'variables': The variables for this theme hook as defined in
     *     hook_theme(). If there is more than one implementation and 'variables' is
     *     not specified in a later one, then the previous definition is kept.
     *   - 'render element': The renderable element for this theme hook as defined
     *     in hook_theme(). If there is more than one implementation and
     *     'render element' is not specified in a later one, then the previous
     *     definition is kept.
     *   - 'preprocess functions': See theme() for detailed documentation.
     *   - 'process functions': See theme() for detailed documentation.
     * @param $name
     *   The name of the module, theme engine, base theme engine, theme or base
     *   theme implementing hook_theme().
     * @param $type
     *   One of 'module', 'theme_engine', 'base_theme_engine', 'theme', or
     *   'base_theme'. Unlike regular hooks that can only be implemented by modules,
     *   each of these can implement hook_theme(). _theme_process_registry() is
     *   called in aforementioned order and new entries override older ones. For
     *   example, if a theme hook is both defined by a module and a theme, then the
     *   definition in the theme will be used.
     * @param $theme
     *   The loaded $theme object as returned from list_themes().
     * @param $path
     *   The directory where $name is. For example, modules/system or
     *   themes/bartik.
     *
     * @see theme()
     * @see _theme_process_registry()
     * @see hook_theme()
     * @see list_themes()
     */
    function _theme_process_registry(&$cache, $name, $type, $theme, $path) {
      $result = array();
    
      // Processor functions work in two distinct phases with the process
      // functions always being executed after the preprocess functions.
      $variable_process_phases = array(
        'preprocess functions' => 'preprocess',
        'process functions'    => 'process',
      );
    
      $hook_defaults = array(
        'variables' => TRUE,
        'render element' => TRUE,
        'pattern' => TRUE,
        'base hook' => TRUE,
      );
    
      // Invoke the hook_theme() implementation, process what is returned, and
      // merge it into $cache.
      $function = $name . '_theme';
      if (function_exists($function)) {
        $result = $function($cache, $type, $theme, $path);
        foreach ($result as $hook => $info) {
          // When a theme or engine overrides a module's theme function
          // $result[$hook] will only contain key/value pairs for information being
          // overridden.  Pull the rest of the information from what was defined by
          // an earlier hook.
    
          // Fill in the type and path of the module, theme, or engine that
          // implements this theme function.
          $result[$hook]['type'] = $type;
          $result[$hook]['theme path'] = $path;
    
          // If function and file are omitted, default to standard naming
          // conventions.
          if (!isset($info['template']) && !isset($info['function'])) {
            $result[$hook]['function'] = ($type == 'module' ? 'theme_' : $name . '_') . $hook;
          }
    
          if (isset($cache[$hook]['includes'])) {
            $result[$hook]['includes'] = $cache[$hook]['includes'];
          }
    
          // If the theme implementation defines a file, then also use the path
          // that it defined. Otherwise use the default path. This allows
          // system.module to declare theme functions on behalf of core .include
          // files.
          if (isset($info['file'])) {
            $include_file = isset($info['path']) ? $info['path'] : $path;
            $include_file .= '/' . $info['file'];
            include_once DRUPAL_ROOT . '/' . $include_file;
            $result[$hook]['includes'][] = $include_file;
          }
    
          // If the default keys are not set, use the default values registered
          // by the module.
          if (isset($cache[$hook])) {
            $result[$hook] += array_intersect_key($cache[$hook], $hook_defaults);
          }
    
          // The following apply only to theming hooks implemented as templates.
          if (isset($info['template'])) {
            // Prepend the current theming path when none is set.
            if (!isset($info['path'])) {
              $result[$hook]['template'] = $path . '/templates/' . $info['template'];
            }
            if ($type == 'module') {
              // Add two render engines for modules.
              // @todo Remove and make twig the default engine.
              $render_engines = array(
                '.twig' => 'twig',
                '.tpl.php' => 'phptemplate'
              );
    
              // Find the best engine for this template.
              foreach ($render_engines as $extension => $engine) {
                // Render the output using the template file.
                $template_file = $result[$hook]['template'] . $extension;
                if (isset($info['path'])) {
                  $template_file = $info['path'] . '/' . $template_file;
                }
                if (file_exists($template_file)) {
                  $result[$hook]['template_file'] = $template_file;
                  $result[$hook]['engine'] = $engine;
                  break;
                }
              }
            }
          }
    
          // Allow variable processors for all theming hooks, whether the hook is
          // implemented as a template or as a function.
          foreach ($variable_process_phases as $phase_key => $phase) {
            // Check for existing variable processors. Ensure arrayness.
            if (!isset($info[$phase_key]) || !is_array($info[$phase_key])) {
              $info[$phase_key] = array();
              $prefixes = array();
              if ($type == 'module') {
                // Default variable processor prefix.
                $prefixes[] = 'template';
                // Add all modules so they can intervene with their own variable
                // processors. This allows them to provide variable processors even
                // if they are not the owner of the current hook.
                $prefixes += module_list();
              }
              elseif ($type == 'theme_engine' || $type == 'base_theme_engine') {
                // Theme engines get an extra set that come before the normally
                // named variable processors.
                $prefixes[] = $name . '_engine';
                // The theme engine registers on behalf of the theme using the
                // theme's name.
                $prefixes[] = $theme;
              }
              else {
                // This applies when the theme manually registers their own variable
                // processors.
                $prefixes[] = $name;
              }
              foreach ($prefixes as $prefix) {
                // Only use non-hook-specific variable processors for theming hooks
                // implemented as templates. See theme().
                if (isset($info['template']) && function_exists($prefix . '_' . $phase)) {
                  $info[$phase_key][] = $prefix . '_' . $phase;
                }
                if (function_exists($prefix . '_' . $phase . '_' . $hook)) {
                  $info[$phase_key][] = $prefix . '_' . $phase . '_' . $hook;
                }
              }
            }
            // Check for the override flag and prevent the cached variable
            // processors from being used. This allows themes or theme engines to
            // remove variable processors set earlier in the registry build.
            if (!empty($info['override ' . $phase_key])) {
              // Flag not needed inside the registry.
              unset($result[$hook]['override ' . $phase_key]);
            }
            elseif (isset($cache[$hook][$phase_key]) && is_array($cache[$hook][$phase_key])) {
              $info[$phase_key] = array_merge($cache[$hook][$phase_key], $info[$phase_key]);
            }
            $result[$hook][$phase_key] = $info[$phase_key];
          }
        }
    
        // Merge the newly created theme hooks into the existing cache.
        $cache = $result + $cache;
      }
    
      // Let themes have variable processors even if they didn't register a template.
      if ($type == 'theme' || $type == 'base_theme') {
        foreach ($cache as $hook => $info) {
          // Check only if not registered by the theme or engine.
          if (empty($result[$hook])) {
            foreach ($variable_process_phases as $phase_key => $phase) {
              if (!isset($info[$phase_key])) {
                $cache[$hook][$phase_key] = array();
              }
              // Only use non-hook-specific variable processors for theming hooks
              // implemented as templates. See theme().
              if (isset($info['template']) && function_exists($name . '_' . $phase)) {
                $cache[$hook][$phase_key][] = $name . '_' . $phase;
              }
              if (function_exists($name . '_' . $phase . '_' . $hook)) {
                $cache[$hook][$phase_key][] = $name . '_' . $phase . '_' . $hook;
                $cache[$hook]['theme path'] = $path;
              }
              // Ensure uniqueness.
              $cache[$hook][$phase_key] = array_unique($cache[$hook][$phase_key]);
            }
          }
        }
      }
    }
    
    /**
     * Build the theme registry cache.
     *
     * @param $theme
     *   The loaded $theme object as returned by list_themes().
     * @param $base_theme
     *   An array of loaded $theme objects representing the ancestor themes in
     *   oldest first order.
     * @param $theme_engine
     *   The name of the theme engine.
     */
    function _theme_build_registry($theme, $base_theme, $theme_engine) {
      $cache = array();
      // First, process the theme hooks advertised by modules. This will
      // serve as the basic registry. Since the list of enabled modules is the same
      // regardless of the theme used, this is cached in its own entry to save
      // building it for every theme.
      if ($cached = cache()->get('theme_registry:build:modules')) {
        $cache = $cached->data;
      }
      else {
        foreach (module_implements('theme') as $module) {
          _theme_process_registry($cache, $module, 'module', $module, drupal_get_path('module', $module));
        }
        // Only cache this registry if all modules are loaded.
        if (module_load_all(NULL)) {
          cache()->set("theme_registry:build:modules", $cache, CacheBackendInterface::CACHE_PERMANENT, array('theme_registry' => TRUE));
        }
      }
    
      // Process each base theme.
      foreach ($base_theme as $base) {
        // If the base theme uses a theme engine, process its hooks.
        $base_path = dirname($base->filename);
        if ($theme_engine) {
          _theme_process_registry($cache, $theme_engine, 'base_theme_engine', $base->name, $base_path);
        }
        _theme_process_registry($cache, $base->name, 'base_theme', $base->name, $base_path);
      }
    
      // And then the same thing, but for the theme.
      if ($theme_engine) {
        _theme_process_registry($cache, $theme_engine, 'theme_engine', $theme->name, dirname($theme->filename));
      }
    
      // Finally, hooks provided by the theme itself.
      _theme_process_registry($cache, $theme->name, 'theme', $theme->name, dirname($theme->filename));
    
      // Let modules alter the registry.
      drupal_alter('theme_registry', $cache);
    
      // Optimize the registry to not have empty arrays for functions.
      foreach ($cache as $hook => $info) {
        foreach (array('preprocess functions', 'process functions') as $phase) {
          if (empty($info[$phase])) {
            unset($cache[$hook][$phase]);
          }
        }
      }
      return $cache;
    }
    
    /**
     * Return a list of all currently available themes.
     *
     * Retrieved from the database, if available and the site is not in maintenance
     * mode; otherwise compiled freshly from the filesystem.
     *
     * @param $refresh
     *   Whether to reload the list of themes from the database. Defaults to FALSE.
     *
     * @return
     *   An associative array of the currently available themes. The keys are the
     *   themes' machine names and the values are objects having the following
     *   properties:
     *   - filename: The filepath and name of the .info file.
     *   - name: The machine name of the theme.
     *   - status: 1 for enabled, 0 for disabled themes.
     *   - info: The contents of the .info file.
     *   - stylesheets: A two dimensional array, using the first key for the
     *     media attribute (e.g. 'all'), the second for the name of the file
     *     (e.g. style.css). The value is a complete filepath (e.g.
     *     themes/bartik/style.css). Not set if no stylesheets are defined in the
     *     .info file.
     *   - scripts: An associative array of JavaScripts, using the filename as key
     *     and the complete filepath as value. Not set if no scripts are defined in
     *     the .info file.
     *   - prefix: The base theme engine prefix.
     *   - engine: The machine name of the theme engine.
     *   - base_theme: If this is a sub-theme, the machine name of the base theme
     *     defined in the .info file. Otherwise, the element is not set.
     *   - base_themes: If this is a sub-theme, an associative array of the
     *     base-theme ancestors of this theme, starting with this theme's base
     *     theme, then the base theme's own base theme, etc. Each entry has an
     *     array key equal to the theme's machine name, and a value equal to the
     *     human-readable theme name; if a theme with matching machine name does
     *     not exist in the system, the value will instead be NULL (and since the
     *     system would not know whether that theme itself has a base theme, that
     *     will end the array of base themes). This is not set if the theme is not
     *     a sub-theme.
     *   - sub_themes: An associative array of themes on the system that are
     *     either direct sub-themes (that is, they declare this theme to be
     *     their base theme), direct sub-themes of sub-themes, etc. The keys are
     *     the themes' machine names, and the values are the themes' human-readable
     *     names. This element is not set if there are no themes on the system that
     *     declare this theme as their base theme.
    */
    function list_themes($refresh = FALSE) {
      $list = &drupal_static(__FUNCTION__, array());
    
      if ($refresh) {
        $list = array();
        system_list_reset();
      }
    
      if (empty($list)) {
        $list = array();
        $themes = array();
        // Extract from the database only when it is available.
        // Also check that the site is not in the middle of an install or update.
        if (!defined('MAINTENANCE_MODE')) {
          try {
            $themes = system_list('theme');
          }
          catch (Exception $e) {
            // If the database is not available, rebuild the theme data.
            $themes = _system_rebuild_theme_data();
          }
        }
        else {
          // Scan the installation when the database should not be read.
          $themes = _system_rebuild_theme_data();
        }
    
        foreach ($themes as $theme) {
          foreach ($theme->info['stylesheets'] as $media => $stylesheets) {
            foreach ($stylesheets as $stylesheet => $path) {
              $theme->stylesheets[$media][$stylesheet] = $path;
            }
          }
          foreach ($theme->info['scripts'] as $script => $path) {
            $theme->scripts[$script] = $path;
          }
          if (isset($theme->info['engine'])) {
            $theme->engine = $theme->info['engine'];
          }
          if (isset($theme->info['base theme'])) {
            $theme->base_theme = $theme->info['base theme'];
          }
          // Status is normally retrieved from the database. Add zero values when
          // read from the installation directory to prevent notices.
          if (!isset($theme->status)) {
            $theme->status = 0;
          }
          $list[$theme->name] = $theme;
        }
      }
    
      return $list;
    }
    
    /**
     * Finds all the base themes for the specified theme.
     *
     * Themes can inherit templates and function implementations from earlier
     * themes.
     *
     * @param $themes
     *   An array of available themes.
     * @param $key
     *   The name of the theme whose base we are looking for.
     * @param $used_keys
     *   (optional) A recursion parameter preventing endless loops. Defaults to
     *   NULL.
     *
     * @return
     *   Returns an array of all of the theme's ancestors; the first element's value
     *   will be NULL if an error occurred.
     */
    function drupal_find_base_themes($themes, $key, $used_keys = array()) {
      $base_key = $themes[$key]->info['base theme'];
      // Does the base theme exist?
      if (!isset($themes[$base_key])) {
        return array($base_key => NULL);
      }
    
      $current_base_theme = array($base_key => $themes[$base_key]->info['name']);
    
      // Is the base theme itself a child of another theme?
      if (isset($themes[$base_key]->info['base theme'])) {
        // Do we already know the base themes of this theme?
        if (isset($themes[$base_key]->base_themes)) {
          return $themes[$base_key]->base_themes + $current_base_theme;
        }
        // Prevent loops.
        if (!empty($used_keys[$base_key])) {
          return array($base_key => NULL);
        }
        $used_keys[$base_key] = TRUE;
        return drupal_find_base_themes($themes, $base_key, $used_keys) + $current_base_theme;
      }
      // If we get here, then this is our parent theme.
      return $current_base_theme;
    }
    
    /**
     * Generates themed output.
     *
     * All requests for themed output must go through this function. It examines
     * the request and routes it to the appropriate
     * @link themeable theme function or template @endlink, by checking the theme
     * registry.
     *
     * Most commonly, the first argument to this function is the name of the theme
     * hook. For instance, to theme a taxonomy term, the theme hook name is
     * 'taxonomy_term'. Modules register theme hooks within a hook_theme()
     * implementation and provide a default implementation via a function named
     * theme_HOOK() (e.g., theme_taxonomy_term()) or via a template file named
     * according to the value of the 'template' key registered with the theme hook
     * (see hook_theme() for details). Default templates are implemented with the
     * PHPTemplate rendering engine and are named the same as the theme hook, with
     * underscores changed to hyphens, so for the 'taxonomy_term' theme hook, the
     * default template is 'taxonomy-term.tpl.php'.
     *
     * Themes may also register new theme hooks within a hook_theme()
     * implementation, but it is more common for themes to override default
     * implementations provided by modules than to register entirely new theme
     * hooks. Themes can override a default implementation by implementing a
     * function named THEME_HOOK() (for example, the 'bartik' theme overrides the
     * default implementation of the 'menu_tree' theme hook by implementing a
     * bartik_menu_tree() function), or by adding a template file within its folder
     * structure that follows the template naming structure used by the theme's
     * rendering engine (for example, since the Bartik theme uses the PHPTemplate
     * rendering engine, it overrides the default implementation of the 'page' theme
     * hook by containing a 'page.tpl.php' file within its folder structure).
     *
     * If the implementation is a template file, several functions are called
     * before the template file is invoked, to modify the $variables array. These
     * fall into the "preprocessing" phase and the "processing" phase, and are
     * executed (if they exist), in the following order (note that in the following
     * list, HOOK indicates the theme hook name, MODULE indicates a module name,
     * THEME indicates a theme name, and ENGINE indicates a theme engine name):
     * - template_preprocess(&$variables, $hook): Creates a default set of variables
     *   for all theme hooks with template implementations.
     * - template_preprocess_HOOK(&$variables): Should be implemented by the module
     *   that registers the theme hook, to set up default variables.
     * - MODULE_preprocess(&$variables, $hook): hook_preprocess() is invoked on all
     *   implementing modules.
     * - MODULE_preprocess_HOOK(&$variables): hook_preprocess_HOOK() is invoked on
     *   all implementing modules, so that modules that didn't define the theme hook
     *   can alter the variables.
     * - ENGINE_engine_preprocess(&$variables, $hook): Allows the theme engine to
     *   set necessary variables for all theme hooks with template implementations.
     * - ENGINE_engine_preprocess_HOOK(&$variables): Allows the theme engine to set
     *   necessary variables for the particular theme hook.
     * - THEME_preprocess(&$variables, $hook): Allows the theme to set necessary
     *   variables for all theme hooks with template implementations.
     * - THEME_preprocess_HOOK(&$variables): Allows the theme to set necessary
     *   variables specific to the particular theme hook.
     * - template_process(&$variables, $hook): Creates an additional set of default
     *   variables for all theme hooks with template implementations. The variables
     *   created in this function are derived from ones created by
     *   template_preprocess(), but potentially altered by the other preprocess
     *   functions listed above. For example, any preprocess function can add to or
     *   modify the $variables['attributes_array'] variable, and after all of them
     *   have finished executing, template_process() flattens it into a
     *   $variables['attributes'] string for convenient use by templates.
     * - template_process_HOOK(&$variables): Should be implemented by the module
     *   that registers the theme hook, if it needs to perform additional variable
     *   processing after all preprocess functions have finished.
     * - MODULE_process(&$variables, $hook): hook_process() is invoked on all
     *   implementing modules.
     * - MODULE_process_HOOK(&$variables): hook_process_HOOK() is invoked on
     *   on all implementing modules, so that modules that didn't define the theme
     *   hook can alter the variables.
     * - ENGINE_engine_process(&$variables, $hook): Allows the theme engine to
     *   process variables for all theme hooks with template implementations.
     * - ENGINE_engine_process_HOOK(&$variables): Allows the theme engine to process
     *   the variables specific to the theme hook.
     * - THEME_process(&$variables, $hook):  Allows the theme to process the
     *   variables for all theme hooks with template implementations.
     * - THEME_process_HOOK(&$variables):  Allows the theme to process the
     *   variables specific to the theme hook.
     *
     * If the implementation is a function, only the theme-hook-specific preprocess
     * and process functions (the ones ending in _HOOK) are called from the
     * list above. This is because theme hooks with function implementations
     * need to be fast, and calling the non-theme-hook-specific preprocess and
     * process functions for them would incur a noticeable performance penalty.
     *
     * There are two special variables that these preprocess and process functions
     * can set: 'theme_hook_suggestion' and 'theme_hook_suggestions'. These will be
     * merged together to form a list of 'suggested' alternate theme hooks to use,
     * in reverse order of priority. theme_hook_suggestion will always be a higher
     * priority than items in theme_hook_suggestions. theme() will use the
     * highest priority implementation that exists. If none exists, theme() will
     * use the implementation for the theme hook it was called with. These
     * suggestions are similar to and are used for similar reasons as calling
     * theme() with an array as the $hook parameter (see below). The difference
     * is whether the suggestions are determined by the code that calls theme() or
     * by a preprocess or process function.
     *
     * @param $hook
     *   The name of the theme hook to call. If the name contains a
     *   double-underscore ('__') and there isn't an implementation for the full
     *   name, the part before the '__' is checked. This allows a fallback to a more
     *   generic implementation. For example, if theme('links__node', ...) is
     *   called, but there is no implementation of that theme hook, then the 'links'
     *   implementation is used. This process is iterative, so if
     *   theme('links__contextual__node', ...) is called, theme() checks for the
     *   following implementations, and uses the first one that exists:
     *   - links__contextual__node
     *   - links__contextual
     *   - links
     *   This allows themes to create specific theme implementations for named
     *   objects and contexts of otherwise generic theme hooks. The $hook parameter
     *   may also be an array, in which case the first theme hook that has an
     *   implementation is used. This allows for the code that calls theme() to
     *   explicitly specify the fallback order in a situation where using the '__'
     *   convention is not desired or is insufficient.
     * @param $variables
     *   An associative array of variables to merge with defaults from the theme
     *   registry, pass to preprocess and process functions for modification, and
     *   finally, pass to the function or template implementing the theme hook.
     *   Alternatively, this can be a renderable array, in which case, its
     *   properties are mapped to variables expected by the theme hook
     *   implementations.
     *
     * @return
     *   An HTML string representing the themed output.
     *
     * @see themeable
     * @see hook_theme()
     * @see template_preprocess()
     * @see template_process()
     */
    function theme($hook, $variables = array()) {
      // If called before all modules are loaded, we do not necessarily have a full
      // theme registry to work with, and therefore cannot process the theme
      // request properly. See also _theme_load_registry().
      if (!module_load_all(NULL) && !defined('MAINTENANCE_MODE')) {
        throw new Exception(t('theme() may not be called until all modules are loaded.'));
      }
    
      $hooks = theme_get_registry(FALSE);
    
      // If an array of hook candidates were passed, use the first one that has an
      // implementation.
      if (is_array($hook)) {
        foreach ($hook as $candidate) {
          if (isset($hooks[$candidate])) {
            break;
          }
        }
        $hook = $candidate;
      }
      // Save the original theme hook, so it can be supplied to theme variable
      // preprocess callbacks.
      $original_hook = $hook;
    
      // If there's no implementation, check for more generic fallbacks. If there's
      // still no implementation, log an error and return an empty string.
      if (!isset($hooks[$hook])) {
        // Iteratively strip everything after the last '__' delimiter, until an
        // implementation is found.
        while ($pos = strrpos($hook, '__')) {
          $hook = substr($hook, 0, $pos);
          if (isset($hooks[$hook])) {
            break;
          }
        }
        if (!isset($hooks[$hook])) {
          // Only log a message when not trying theme suggestions ($hook being an
          // array).
          if (!isset($candidate)) {
            watchdog('theme', 'Theme hook %hook not found.', array('%hook' => $hook), WATCHDOG_WARNING);
          }
          return '';
        }
      }
    
      $info = $hooks[$hook];
      global $theme_path;
      $temp = $theme_path;
      // point path_to_theme() to the currently used theme path:
      $theme_path = $info['theme path'];
    
      // Include a file if the theme function or variable processor is held elsewhere.
      if (!empty($info['includes'])) {
        foreach ($info['includes'] as $include_file) {
          include_once DRUPAL_ROOT . '/' . $include_file;
        }
      }
    
      // If a renderable array is passed as $variables, then set $variables to
      // the arguments expected by the theme function.
      if (isset($variables['#theme']) || isset($variables['#theme_wrappers'])) {
        $element = $variables;
        $variables = array();
        if (isset($info['variables'])) {
          foreach (array_keys($info['variables']) as $name) {
            if (isset($element["#$name"])) {
              $variables[$name] = $element["#$name"];
            }
          }
        }
        else {
          $variables[$info['render element']] = $element;
        }
      }
    
      // Merge in argument defaults.
      if (!empty($info['variables'])) {
        $variables += $info['variables'];
      }
      elseif (!empty($info['render element'])) {
        $variables += array($info['render element'] => array());
      }
      // Supply original caller info.
      $variables += array(
        'theme_hook_original' => $original_hook,
      );
    
      // Invoke the variable processors, if any. The processors may specify
      // alternate suggestions for which hook's template/function to use. If the
      // hook is a suggestion of a base hook, invoke the variable processors of
      // the base hook, but retain the suggestion as a high priority suggestion to
      // be used unless overridden by a variable processor function.
      if (isset($info['base hook'])) {
        $base_hook = $info['base hook'];
        $base_hook_info = $hooks[$base_hook];
        // Include files required by the base hook, since its variable processors
        // might reside there.
        if (!empty($base_hook_info['includes'])) {
          foreach ($base_hook_info['includes'] as $include_file) {
            include_once DRUPAL_ROOT . '/' . $include_file;
          }
        }
        if (isset($base_hook_info['preprocess functions']) || isset($base_hook_info['process functions'])) {
          $variables['theme_hook_suggestion'] = $hook;
          $hook = $base_hook;
          $info = $base_hook_info;
        }
      }
      if (isset($info['preprocess functions']) || isset($info['process functions'])) {
        $variables['theme_hook_suggestions'] = array();
        foreach (array('preprocess functions', 'process functions') as $phase) {
          if (!empty($info[$phase])) {
            foreach ($info[$phase] as $processor_function) {
              if (function_exists($processor_function)) {
                // We don't want a poorly behaved process function changing $hook.
                $hook_clone = $hook;
                $processor_function($variables, $hook_clone);
              }
            }
          }
        }
        // If the preprocess/process functions specified hook suggestions, and the
        // suggestion exists in the theme registry, use it instead of the hook that
        // theme() was called with. This allows the preprocess/process step to
        // route to a more specific theme hook. For example, a function may call
        // theme('node', ...), but a preprocess function can add 'node__article' as
        // a suggestion, enabling a theme to have an alternate template file for
        // article nodes. Suggestions are checked in the following order:
        // - The 'theme_hook_suggestion' variable is checked first. It overrides
        //   all others.
        // - The 'theme_hook_suggestions' variable is checked in FILO order, so the
        //   last suggestion added to the array takes precedence over suggestions
        //   added earlier.
        $suggestions = array();
        if (!empty($variables['theme_hook_suggestions'])) {
          $suggestions = $variables['theme_hook_suggestions'];
        }
        if (!empty($variables['theme_hook_suggestion'])) {
          $suggestions[] = $variables['theme_hook_suggestion'];
        }
        foreach (array_reverse($suggestions) as $suggestion) {
          if (isset($hooks[$suggestion])) {
            $info = $hooks[$suggestion];
            break;
          }
        }
      }
    
      // Generate the output using either a function or a template.
      $output = '';
      if (isset($info['function'])) {
        if (function_exists($info['function'])) {
          $output = $info['function']($variables);
        }
      }
      else {
        // Default render function and extension.
        $render_function = 'theme_render_template';
        $extension = '.tpl.php';
    
        // The theme engine may use a different extension and a different renderer.
        global $theme_engine;
        if (isset($theme_engine)) {
          if ($info['type'] != 'module') {
            if (function_exists($theme_engine . '_render_template')) {
              $render_function = $theme_engine . '_render_template';
            }
            $extension_function = $theme_engine . '_extension';
            if (function_exists($extension_function)) {
              $extension = $extension_function();
            }
          }
          elseif (isset($info['engine'])) {
            if (function_exists($info['engine'] . '_render_template')) {
              $render_function = $info['engine'] . '_render_template';
            }
          }
        }
    
        // In some cases, a template implementation may not have had
        // template_preprocess() run (for example, if the default implementation is
        // a function, but a template overrides that default implementation). In
        // these cases, a template should still be able to expect to have access to
        // the variables provided by template_preprocess(), so we add them here if
        // they don't already exist. We don't want to run template_preprocess()
        // twice (it would be inefficient and mess up zebra striping), so we use the
        // 'directory' variable to determine if it has already run, which while not
        // completely intuitive, is reasonably safe, and allows us to save on the
        // overhead of adding some new variable to track that.
        if (!isset($variables['directory'])) {
          $default_template_variables = array();
          template_preprocess($default_template_variables, $hook);
          $variables += $default_template_variables;
        }
    
        // Render the output using the template file.
        $template_file = $info['template'] . $extension;
        if (isset($info['path'])) {
          $template_file = $info['path'] . '/' . $template_file;
        }
    
        // Modules can override this.
        if (isset($info['template_file'])) {
          $template_file = $info['template_file'];
        }
    
        $output = $render_function($template_file, $variables);
      }
    
      // restore path_to_theme()
      $theme_path = $temp;
      return $output;
    }
    
    /**
     * Return the path to the current themed element.
     *
     * It can point to the active theme or the module handling a themed implementation.
     * For example, when invoked within the scope of a theming call it will depend
     * on where the theming function is handled. If implemented from a module, it
     * will point to the module. If implemented from the active theme, it will point
     * to the active theme. When called outside the scope of a theming call, it will
     * always point to the active theme.
     */
    function path_to_theme() {
      global $theme_path;
    
      if (!isset($theme_path)) {
        drupal_theme_initialize();
      }
    
      return $theme_path;
    }
    
    /**
     * Allow themes and/or theme engines to easily discover overridden theme functions.
     *
     * @param $cache
     *   The existing cache of theme hooks to test against.
     * @param $prefixes
     *   An array of prefixes to test, in reverse order of importance.
     *
     * @return $implementations
     *   The functions found, suitable for returning from hook_theme;
     */
    function drupal_find_theme_functions($cache, $prefixes) {
      $implementations = array();
      $functions = get_defined_functions();
    
      foreach ($cache as $hook => $info) {
        foreach ($prefixes as $prefix) {
          // Find theme functions that implement possible "suggestion" variants of
          // registered theme hooks and add those as new registered theme hooks.
          // The 'pattern' key defines a common prefix that all suggestions must
          // start with. The default is the name of the hook followed by '__'. An
          // 'base hook' key is added to each entry made for a found suggestion,
          // so that common functionality can be implemented for all suggestions of
          // the same base hook. To keep things simple, deep hierarchy of
          // suggestions is not supported: each suggestion's 'base hook' key
          // refers to a base hook, not to another suggestion, and all suggestions
          // are found using the base hook's pattern, not a pattern from an
          // intermediary suggestion.
          $pattern = isset($info['pattern']) ? $info['pattern'] : ($hook . '__');
          if (!isset($info['base hook']) && !empty($pattern)) {
            $matches = preg_grep('/^' . $prefix . '_' . $pattern . '/', $functions['user']);
            if ($matches) {
              foreach ($matches as $match) {
                $new_hook = substr($match, strlen($prefix) + 1);
                $arg_name = isset($info['variables']) ? 'variables' : 'render element';
                $implementations[$new_hook] = array(
                  'function' => $match,
                  $arg_name => $info[$arg_name],
                  'base hook' => $hook,
                );
              }
            }
          }
          // Find theme functions that implement registered theme hooks and include
          // that in what is returned so that the registry knows that the theme has
          // this implementation.
          if (function_exists($prefix . '_' . $hook)) {
            $implementations[$hook] = array(
              'function' => $prefix . '_' . $hook,
            );
          }
        }
      }
    
      return $implementations;
    }
    
    /**
     * Allow themes and/or theme engines to easily discover overridden templates.
     *
     * @param $cache
     *   The existing cache of theme hooks to test against.
     * @param $extension
     *   The extension that these templates will have.
     * @param $path
     *   The path to search.
     */
    function drupal_find_theme_templates($cache, $extension, $path) {
      $implementations = array();
    
      // Collect paths to all sub-themes grouped by base themes. These will be
      // used for filtering. This allows base themes to have sub-themes in its
      // folder hierarchy without affecting the base themes template discovery.
      $theme_paths = array();
      foreach (list_themes() as $theme_info) {
        if (!empty($theme_info->base_theme)) {
          $theme_paths[$theme_info->base_theme][$theme_info->name] = dirname($theme_info->filename);
        }
      }
      foreach ($theme_paths as $basetheme => $subthemes) {
        foreach ($subthemes as $subtheme => $subtheme_path) {
          if (isset($theme_paths[$subtheme])) {
            $theme_paths[$basetheme] = array_merge($theme_paths[$basetheme], $theme_paths[$subtheme]);
          }
        }
      }
      global $theme;
      $subtheme_paths = isset($theme_paths[$theme]) ? $theme_paths[$theme] : array();
    
      // Escape the periods in the extension.
      $regex = '/' . str_replace('.', '\.', $extension) . '$/';
      // Get a listing of all template files in the path to search.
      $files = file_scan_directory($path, $regex, array('key' => 'name'));
    
      // Find templates that implement registered theme hooks and include that in
      // what is returned so that the registry knows that the theme has this
      // implementation.
      foreach ($files as $template => $file) {
        // Ignore sub-theme templates for the current theme.
        if (strpos($file->uri, str_replace($subtheme_paths, '', $file->uri)) !== 0) {
          continue;
        }
        // Chop off the remaining '.tpl' extension. $template already has the
        // rightmost extension removed, but there might still be more, such as with
        // .tpl.php, which still has .tpl in $template at this point.
        if (($pos = strpos($template, '.tpl')) !== FALSE) {
          $template = substr($template, 0, $pos);
        }
        // Transform - in filenames to _ to match function naming scheme
        // for the purposes of searching.
        $hook = strtr($template, '-', '_');
        if (isset($cache[$hook])) {
          $implementations[$hook] = array(
            'template' => $template,
            'path' => dirname($file->uri),
          );
        }
    
        // Match templates based on the 'template' filename.
        foreach ($cache as $hook => $info) {
          if (isset($info['template'])) {
            $template_candidates = array($info['template'], str_replace($info['theme path'] . '/templates/', '', $info['template']));
            if (in_array($template, $template_candidates)) {
              $implementations[$hook] = array(
                'template' => $template,
                'path' => dirname($file->uri),
              );
            }
          }
        }
      }
    
      // Find templates that implement possible "suggestion" variants of registered
      // theme hooks and add those as new registered theme hooks. See
      // drupal_find_theme_functions() for more information about suggestions and
      // the use of 'pattern' and 'base hook'.
      $patterns = array_keys($files);
      foreach ($cache as $hook => $info) {
        $pattern = isset($info['pattern']) ? $info['pattern'] : ($hook . '__');
        if (!isset($info['base hook']) && !empty($pattern)) {
          // Transform _ in pattern to - to match file naming scheme
          // for the purposes of searching.
          $pattern = strtr($pattern, '_', '-');
    
          $matches = preg_grep('/^' . $pattern . '/', $patterns);
          if ($matches) {
            foreach ($matches as $match) {
              $file = $match;
              // Chop off the remaining extensions if there are any. $template
              // already has the rightmost extension removed, but there might still
              // be more, such as with .tpl.php, which still has .tpl in $template
              // at this point.
              if (($pos = strpos($match, '.')) !== FALSE) {
                $file = substr($match, 0, $pos);
              }
              // Put the underscores back in for the hook name and register this pattern.
              $arg_name = isset($info['variables']) ? 'variables' : 'render element';
              $implementations[strtr($file, '-', '_')] = array(
                'template' => $file,
                'path' => dirname($files[$match]->uri),
                $arg_name => $info[$arg_name],
                'base hook' => $hook,
              );
            }
          }
        }
      }
      return $implementations;
    }
    
    /**
     * Retrieve a setting for the current theme or for a given theme.
     *
     * The final setting is obtained from the last value found in the following
     * sources:
     * - the default global settings specified in this function
     * - the default theme-specific settings defined in any base theme's .info file
     * - the default theme-specific settings defined in the theme's .info file
     * - the saved values from the global theme settings form
     * - the saved values from the theme's settings form
     * To only retrieve the default global theme setting, an empty string should be
     * given for $theme.
     *
     * @param $setting_name
     *   The name of the setting to be retrieved.
     * @param $theme
     *   The name of a given theme; defaults to the current theme.
     *
     * @return
     *   The value of the requested setting, NULL if the setting does not exist.
     */
    function theme_get_setting($setting_name, $theme = NULL) {
      $cache = &drupal_static(__FUNCTION__, array());
    
      // If no key is given, use the current theme if we can determine it.
      if (!isset($theme)) {
        $theme = !empty($GLOBALS['theme_key']) ? $GLOBALS['theme_key'] : '';
      }
    
      if (empty($cache[$theme])) {
        // Set the default values for each global setting.
        // To add new global settings, add their default values below, and then
        // add form elements to system_theme_settings() in system.admin.inc.
        $cache[$theme] = array(
          'default_logo'                     =>  1,
          'logo_path'                        =>  '',
          'default_favicon'                  =>  1,
          'favicon_path'                     =>  '',
          // Use the IANA-registered MIME type for ICO files as default.
          'favicon_mimetype'                 =>  'image/vnd.microsoft.icon',
        );
        // Turn on all default features.
        $features = _system_default_theme_features();
        foreach ($features as $feature) {
          $cache[$theme]['toggle_' . $feature] = 1;
        }
    
        // Get the values for the theme-specific settings from the .info files of
        // the theme and all its base themes.
        if ($theme) {
          $themes = list_themes();
          $theme_object = $themes[$theme];
    
          // Create a list which includes the current theme and all its base themes.
          if (isset($theme_object->base_themes)) {
            $theme_keys = array_keys($theme_object->base_themes);
            $theme_keys[] = $theme;
          }
          else {
            $theme_keys = array($theme);
          }
          foreach ($theme_keys as $theme_key) {
            if (!empty($themes[$theme_key]->info['settings'])) {
              $cache[$theme] = array_merge($cache[$theme], $themes[$theme_key]->info['settings']);
            }
          }
        }
    
        // Get the saved global settings from the database.
        $cache[$theme] = array_merge($cache[$theme], variable_get('theme_settings', array()));
    
        if ($theme) {
          // Get the saved theme-specific settings from the database.
          $cache[$theme] = array_merge($cache[$theme], variable_get('theme_' . $theme . '_settings', array()));
    
          // If the theme does not support a particular feature, override the global
          // setting and set the value to NULL.
          if (!empty($theme_object->info['features'])) {
            foreach ($features as $feature) {
              if (!in_array($feature, $theme_object->info['features'])) {
                $cache[$theme]['toggle_' . $feature] = NULL;
              }
            }
          }
    
          // Generate the path to the logo image.
          if ($cache[$theme]['toggle_logo']) {
            if ($cache[$theme]['default_logo']) {
              $cache[$theme]['logo'] = file_create_url(dirname($theme_object->filename) . '/logo.png');
            }
            elseif ($cache[$theme]['logo_path']) {
              $cache[$theme]['logo'] = file_create_url($cache[$theme]['logo_path']);
            }
          }
    
          // Generate the path to the favicon.
          if ($cache[$theme]['toggle_favicon']) {
            if ($cache[$theme]['default_favicon']) {
              if (file_exists($favicon = dirname($theme_object->filename) . '/favicon.ico')) {
                $cache[$theme]['favicon'] = file_create_url($favicon);
              }
              else {
                $cache[$theme]['favicon'] = file_create_url('core/misc/favicon.ico');
              }
            }
            elseif ($cache[$theme]['favicon_path']) {
              $cache[$theme]['favicon'] = file_create_url($cache[$theme]['favicon_path']);
            }
            else {
              $cache[$theme]['toggle_favicon'] = FALSE;
            }
          }
        }
      }
    
      return isset($cache[$theme][$setting_name]) ? $cache[$theme][$setting_name] : NULL;
    }
    
    /**
     * Render a system default template, which is essentially a PHP template.
     *
     * @param $template_file
     *   The filename of the template to render.
     * @param $variables
     *   A keyed array of variables that will appear in the output.
     *
     * @return
     *   The output generated by the template.
     */
    function theme_render_template($template_file, $variables) {
      extract($variables, EXTR_SKIP);               // Extract the variables to a local namespace
      ob_start();                                   // Start output buffering
      include DRUPAL_ROOT . '/' . $template_file;   // Include the template file
      return ob_get_clean();                        // End buffering and return its contents
    }
    
    /**
     * Enable a given list of themes.
     *
     * @param $theme_list
     *   An array of theme names.
     */
    function theme_enable($theme_list) {
      drupal_clear_css_cache();
      $theme_config = config('system.theme');
      $disabled_themes = config('system.theme.disabled');
      foreach ($theme_list as $key) {
        // The value is not used; the weight is ignored for themes currently.
        $theme_config->set("enabled.$key", 0);
        $disabled_themes->clear($key);
        // Install default configuration of the theme.
        config_install_default_config('theme', $key);
      }
      $theme_config->save();
      $disabled_themes->save();
    
      list_themes(TRUE);
      menu_router_rebuild();
      drupal_theme_rebuild();
    
      // Invoke hook_themes_enabled() after the themes have been enabled.
      module_invoke_all('themes_enabled', $theme_list);
    }
    
    /**
     * Disable a given list of themes.
     *
     * @param $theme_list
     *   An array of theme names.
     */
    function theme_disable($theme_list) {
      // Don't disable the default theme.
      if ($pos = array_search(variable_get('theme_default', 'stark'), $theme_list) !== FALSE) {
        unset($theme_list[$pos]);
        if (empty($theme_list)) {
          return;
        }
      }
    
      drupal_clear_css_cache();
    
      $theme_config = config('system.theme');
      $disabled_themes = config('system.theme.disabled');
      foreach ($theme_list as $key) {
        // The value is not used; the weight is ignored for themes currently.
        $theme_config->clear("enabled.$key");
        $disabled_themes->set($key, 0);
      }
      $theme_config->save();
      $disabled_themes->save();
    
      list_themes(TRUE);
      menu_router_rebuild();
      drupal_theme_rebuild();
    
      // Invoke hook_themes_disabled after the themes have been disabled.
      module_invoke_all('themes_disabled', $theme_list);
    }
    
    /**
     * @addtogroup themeable
     * @{
     */
    
    /**
     * Preprocess variables for theme_datetime().
     */
    function template_preprocess_datetime(&$variables) {
      // Format the 'datetime' attribute based on the timestamp.
      // @see http://www.w3.org/TR/html5-author/the-time-element.html#attr-time-datetime
      if (!isset($variables['attributes']['datetime']) && isset($variables['timestamp'])) {
        $variables['attributes']['datetime'] = format_date($variables['timestamp'], 'html_datetime', '', 'UTC');
      }
    
      // If no text was provided, try to auto-generate it.
      if (!isset($variables['text'])) {
        // Format and use a human-readable version of the timestamp, if any.
        if (isset($variables['timestamp'])) {
          $variables['text'] = format_date($variables['timestamp']);
          $variables['html'] = FALSE;
        }
        // Otherwise, use the literal datetime attribute.
        elseif (isset($variables['attributes']['datetime'])) {
          $variables['text'] = $variables['attributes']['datetime'];
          $variables['html'] = FALSE;
        }
      }
    }
    
    /**
     * Returns HTML for a date / time.
     *
     * @param $variables
     *   An associative array containing:
     *   - timestamp: (optional) A UNIX timestamp for the datetime attribute. If the
     *     datetime cannot be represented as a UNIX timestamp, use a valid datetime
     *     attribute value in $variables['attributes']['datetime'].
     *   - text: (optional) The content to display within the <time> element. Set
     *     'html' to TRUE if this value is already sanitized for output in HTML.
     *     Defaults to a human-readable representation of the timestamp value or the
     *     datetime attribute value using format_date().
     *     When invoked as #theme or #theme_wrappers of a render element, the
     *     rendered #children are autoamtically taken over as 'text', unless #text
     *     is explicitly set.
     *   - attributes: (optional) An associative array of HTML attributes to apply
     *     to the <time> element. A datetime attribute in 'attributes' overrides the
     *     'timestamp'. To create a valid datetime attribute value from a UNIX
     *     timestamp, use format_date() with one of the predefined 'html_*' formats.
     *   - html: (optional) Whether 'text' is HTML markup (TRUE) or plain-text
     *     (FALSE). Defaults to FALSE. For example, to use a SPAN tag within the
     *     TIME element, this must be set to TRUE, or the SPAN tag will be escaped.
     *     It is the responsibility of the caller to properly sanitize the value
     *     contained in 'text' (or within the SPAN tag in aforementioned example).
     *
     * @see template_preprocess_datetime()
     * @see http://www.w3.org/TR/html5-author/the-time-element.html#attr-time-datetime
     */
    function theme_datetime($variables) {
      $output = '<time' . new Attribute($variables['attributes']) . '>';
      $output .= !empty($variables['html']) ? $variables['text'] : check_plain($variables['text']);
      $output .= '</time>';
      return $output;
    }
    
    /**
     * Returns HTML for status and/or error messages, grouped by type.
     *
     * An invisible heading identifies the messages for assistive technology.
     * Sighted users see a colored box. See http://www.w3.org/TR/WCAG-TECHS/H69.html
     * for info.
     *
     * @param $variables
     *   An associative array containing:
     *   - display: (optional) Set to 'status' or 'error' to display only messages
     *     of that type.
     */
    function theme_status_messages($variables) {
      $display = $variables['display'];
      $output = '';
    
      $status_heading = array(
        'status' => t('Status message'),
        'error' => t('Error message'),
        'warning' => t('Warning message'),
      );
      foreach (drupal_get_messages($display) as $type => $messages) {
        $output .= "<div class=\"messages $type\">\n";
        if (!empty($status_heading[$type])) {
          $output .= '<h2 class="element-invisible">' . $status_heading[$type] . "</h2>\n";
        }
        if (count($messages) > 1) {
          $output .= " <ul>\n";
          foreach ($messages as $message) {
            $output .= '  <li>' . $message . "</li>\n";
          }
          $output .= " </ul>\n";
        }
        else {
          $output .= $messages[0];
        }
        $output .= "</div>\n";
      }
      return $output;
    }
    
    /**
     * Returns HTML for a link.
     *
     * All Drupal code that outputs a link should call the l() function. That
     * function performs some initial preprocessing, and then, if necessary, calls
     * theme('link') for rendering the anchor tag.
     *
     * To optimize performance for sites that don't need custom theming of links,
     * the l() function includes an inline copy of this function, and uses that copy
     * if none of the enabled modules or the active theme implement any preprocess
     * or process functions or override this theme implementation.
     *
     * @param $variables
     *   An associative array containing the keys 'text', 'path', and 'options'. See
     *   the l() function for information about these variables.
     *
     * @see l()
     */
    function theme_link($variables) {
      return '<a href="' . check_plain(url($variables['path'], $variables['options'])) . '"' . new Attribute($variables['options']['attributes']) . '>' . ($variables['options']['html'] ? $variables['text'] : check_plain($variables['text'])) . '</a>';
    }
    
    /**
     * Returns HTML for a set of links.
     *
     * @param $variables
     *   An associative array containing:
     *   - links: An associative array of links to be themed. The key for each link
     *     is used as its CSS class. Each link should be itself an array, with the
     *     following elements:
     *     - title: The link text.
     *     - href: The link URL. If omitted, the 'title' is shown as a plain text
     *       item in the links list.
     *     - html: (optional) Whether or not 'title' is HTML. If set, the title
     *       will not be passed through check_plain().
     *     - attributes: (optional) Attributes for the anchor, or for the <span> tag
     *       used in its place if no 'href' is supplied. If element 'class' is
     *       included, it must be an array of one or more class names.
     *     If the 'href' element is supplied, the entire link array is passed to l()
     *     as its $options parameter.
     *   - attributes: A keyed array of attributes for the UL containing the
     *     list of links.
     *   - heading: (optional) A heading to precede the links. May be an associative
     *     array or a string. If it's an array, it can have the following elements:
     *     - text: The heading text.
     *     - level: The heading level (e.g. 'h2', 'h3').
     *     - class: (optional) An array of the CSS classes for the heading.
     *     When using a string it will be used as the text of the heading and the
     *     level will default to 'h2'. Headings should be used on navigation menus
     *     and any list of links that consistently appears on multiple pages. To
     *     make the heading invisible use the 'element-invisible' CSS class. Do not
     *     use 'display:none', which removes it from screen-readers and assistive
     *     technology. Headings allow screen-reader and keyboard only users to
     *     navigate to or skip the links. See
     *     http://juicystudio.com/article/screen-readers-display-none.php and
     *     http://www.w3.org/TR/WCAG-TECHS/H42.html for more information.
     */
    function theme_links($variables) {
      $language_url = language(LANGUAGE_TYPE_URL);
    
      $links = $variables['links'];
      $attributes = $variables['attributes'];
      $heading = $variables['heading'];
      $output = '';
    
      if (!empty($links)) {
        // Prepend the heading to the list, if any.
        if (!empty($heading)) {
          // Convert a string heading into an array, using a H2 tag by default.
          if (is_string($heading)) {
            $heading = array('text' => $heading);
          }
          // Merge in default array properties into $heading.
          $heading += array(
            'level' => 'h2',
            'attributes' => array(),
          );
          // @todo Remove backwards compatibility for $heading['class'].
          if (isset($heading['class'])) {
            $heading['attributes']['class'] = $heading['class'];
          }
    
          $output .= '<' . $heading['level'] . new Attribute($heading['attributes']) . '>';
          $output .= check_plain($heading['text']);
          $output .= '</' . $heading['level'] . '>';
        }
    
        $output .= '<ul' . new Attribute($attributes) . '>';
    
        $num_links = count($links);
        $i = 0;
        foreach ($links as $key => $link) {
          $i++;
    
          $class = array();
          // Use the array key as class name.
          $class[] = drupal_html_class($key);
          // Add odd/even, first, and last classes.
          $class[] = ($i % 2 ? 'odd' : 'even');
          if ($i == 1) {
            $class[] = 'first';
          }
          if ($i == $num_links) {
            $class[] = 'last';
          }
    
          // Handle links.
          if (isset($link['href'])) {
            $is_current_path = ($link['href'] == current_path() || ($link['href'] == '<front>' && drupal_is_front_page()));
            $is_current_language = (empty($link['language']) || $link['language']->langcode == $language_url->langcode);
            if ($is_current_path && $is_current_language) {
              $class[] = 'active';
            }
            // Pass in $link as $options, they share the same keys.
            $item = l($link['title'], $link['href'], $link);
          }
          // Handle title-only text items.
          else {
            // Merge in default array properties into $link.
            $link += array(
              'html' => FALSE,
              'attributes' => array(),
            );
            $item = '<span' . new Attribute($link['attributes']) . '>';
            $item .= ($link['html'] ? $link['title'] : check_plain($link['title']));
            $item .= '</span>';
          }
    
          $output .= '<li' . new Attribute(array('class' => $class)) . '>';
          $output .= $item;
          $output .= '</li>';
        }
    
        $output .= '</ul>';
      }
    
      return $output;
    }
    
    /**
     * Returns HTML for wrapping a dropbutton menu.
     *
     * @param array $variables
     *   An associative array containing:
     *   - element: An associative array containing the properties and children of
     *     the dropbutton menu. Properties used: #children.
     */
    function theme_dropbutton_wrapper($variables) {
      if (!empty($variables['element']['#children'])) {
        return '<div class="dropbutton-wrapper"><div class="dropbutton-widget">' . $variables['element']['#children'] . '</div></div>';
      }
    }
    
    /**
     * Returns HTML for an image.
     *
     * @param $variables
     *   An associative array containing:
     *   - uri: Either the path of the image file (relative to base_path()) or a
     *     full URL.
     *   - width: The width of the image (if known).
     *   - height: The height of the image (if known).
     *   - alt: The alternative text for text-based browsers. HTML 4 and XHTML 1.0
     *     always require an alt attribute. The HTML 5 draft allows the alt
     *     attribute to be omitted in some cases. Therefore, this variable defaults
     *     to an empty string, but can be set to NULL for the attribute to be
     *     omitted. Usually, neither omission nor an empty string satisfies
     *     accessibility requirements, so it is strongly encouraged for code calling
     *     theme('image') to pass a meaningful value for this variable.
     *     - http://www.w3.org/TR/REC-html40/struct/objects.html#h-13.8
     *     - http://www.w3.org/TR/xhtml1/dtds.html
     *     - http://dev.w3.org/html5/spec/Overview.html#alt
     *   - title: The title text is displayed when the image is hovered in some
     *     popular browsers.
     *   - attributes: Associative array of attributes to be placed in the img tag.
     */
    function theme_image($variables) {
      $attributes = $variables['attributes'];
      $attributes['src'] = file_create_url($variables['uri']);
    
      foreach (array('width', 'height', 'alt', 'title') as $key) {
        if (isset($variables[$key])) {
          $attributes[$key] = $variables[$key];
        }
      }
    
      return '<img' . new Attribute($attributes) . ' />';
    }
    
    /**
     * Returns HTML for a breadcrumb trail.
     *
     * @param $variables
     *   An associative array containing:
     *   - breadcrumb: An array containing the breadcrumb links.
     */
    function theme_breadcrumb($variables) {
      $breadcrumb = $variables['breadcrumb'];
      $output = '';
      if (!empty($breadcrumb)) {
        $output .= '<nav role="navigation" class="breadcrumb">';
        // Provide a navigational heading to give context for breadcrumb links to
        // screen-reader users. Make the heading invisible with .element-invisible.
        $output .= '<h2 class="element-invisible">' . t('You are here') . '</h2>';
        $output .= '<ol><li>' . implode('</li><li>', $breadcrumb) . '</li></ol>';
        $output .= '</nav>';
      }
      return $output;
    }
    
    /**
     * Returns HTML for a table.
     *
     * @param $variables
     *   An associative array containing:
     *   - header: An array containing the table headers. Each element of the array
     *     can be either a localized string or an associative array with the
     *     following keys:
     *     - "data": The localized title of the table column.
     *     - "field": The database field represented in the table column (required
     *       if user is to be able to sort on this column).
     *     - "sort": A default sort order for this column ("asc" or "desc").
     *     - "class": An array of values for the 'class' attribute. In particular,
     *        the least important columns that can be hidden on narrow and medium
     *        width screens should have a 'priority-low' class, referenced with the
     *        RESPONSIVE_PRIORITY_LOW constant. Columns that should be shown on
     *        medium+ wide screens should be marked up with a class of
     *        'priority-medium', referenced by with the RESPONSIVE_PRIORITY_MEDIUM
     *        constant. Themes may hide columns with one of these two classes on
     *        narrow viewports to save horizontal space.
     *     - Any HTML attributes, such as "colspan", to apply to the column header
     *       cell.
     *   - rows: An array of table rows. Every row is an array of cells, or an
     *     associative array with the following keys:
     *     - "data": an array of cells
     *     - Any HTML attributes, such as "class", to apply to the table row.
     *     - "no_striping": a boolean indicating that the row should receive no
     *       'even / odd' styling. Defaults to FALSE.
     *     Each cell can be either a string or an associative array with the
     *     following keys:
     *     - "data": The string to display in the table cell.
     *     - "header": Indicates this cell is a header.
     *     - Any HTML attributes, such as "colspan", to apply to the table cell.
     *     Here's an example for $rows:
     *     @code
     *     $rows = array(
     *       // Simple row
     *       array(
     *         'Cell 1', 'Cell 2', 'Cell 3'
     *       ),
     *       // Row with attributes on the row and some of its cells.
     *       array(
     *         'data' => array('Cell 1', array('data' => 'Cell 2', 'colspan' => 2)), 'class' => array('funky')
     *       )
     *     );
     *     @endcode
     *   - attributes: An array of HTML attributes to apply to the table tag.
     *   - caption: A localized string to use for the <caption> tag.
     *   - colgroups: An array of column groups. Each element of the array can be
     *     either:
     *     - An array of columns, each of which is an associative array of HTML
     *       attributes applied to the COL element.
     *     - An array of attributes applied to the COLGROUP element, which must
     *       include a "data" attribute. To add attributes to COL elements, set the
     *       "data" attribute with an array of columns, each of which is an
     *       associative array of HTML attributes.
     *     Here's an example for $colgroup:
     *     @code
     *     $colgroup = array(
     *       // COLGROUP with one COL element.
     *       array(
     *         array(
     *           'class' => array('funky'), // Attribute for the COL element.
     *         ),
     *       ),
     *       // Colgroup with attributes and inner COL elements.
     *       array(
     *         'data' => array(
     *           array(
     *             'class' => array('funky'), // Attribute for the COL element.
     *           ),
     *         ),
     *         'class' => array('jazzy'), // Attribute for the COLGROUP element.
     *       ),
     *     );
     *     @endcode
     *     These optional tags are used to group and set properties on columns
     *     within a table. For example, one may easily group three columns and
     *     apply same background style to all.
     *   - sticky: Use a "sticky" table header.
     *   - empty: The message to display in an extra row if table does not have any
     *     rows.
     */
    function theme_table($variables) {
      $header = $variables['header'];
      $rows = $variables['rows'];
      $attributes = $variables['attributes'];
      $caption = $variables['caption'];
      $colgroups = $variables['colgroups'];
      $sticky = $variables['sticky'];
      $responsive = $variables['responsive'];
      $empty = $variables['empty'];
    
      // Add sticky headers, if applicable.
      if (count($header) && $sticky) {
        drupal_add_library('system', 'drupal.tableheader');
        // Add 'sticky-enabled' class to the table to identify it for JS.
        // This is needed to target tables constructed by this function.
        $attributes['class'][] = 'sticky-enabled';
      }
      // If the table has headers and it should react responsively to columns hidden
      // with the classes represented by the constants RESPONSIVE_PRIORITY_MEDIUM
      // and RESPONSIVE_PRIORITY_LOW, add the tableresponsive behaviors.
      if (count($header) && $responsive) {
        drupal_add_library('system', 'drupal.tableresponsive');
        // Add 'responsive-enabled' class to the table to identify it for JS.
        // This is needed to target tables constructed by this function.
        $attributes['class'][] = 'responsive-enabled';
      }
    
      $output = '<table' . new Attribute($attributes) . ">\n";
    
      if (isset($caption)) {
        $output .= '<caption>' . $caption . "</caption>\n";
      }
    
      // Format the table columns:
      if (count($colgroups)) {
        foreach ($colgroups as $number => $colgroup) {
          $attributes = array();
    
          // Check if we're dealing with a simple or complex column
          if (isset($colgroup['data'])) {
            foreach ($colgroup as $key => $value) {
              if ($key == 'data') {
                $cols = $value;
              }
              else {
                $attributes[$key] = $value;
              }
            }
          }
          else {
            $cols = $colgroup;
          }
    
          // Build colgroup
          if (is_array($cols) && count($cols)) {
            $output .= ' <colgroup' . new Attribute($attributes) . '>';
            $i = 0;
            foreach ($cols as $col) {
              $output .= ' <col' . new Attribute($col) . ' />';
            }
            $output .= " </colgroup>\n";
          }
          else {
            $output .= ' <colgroup' . new Attribute($attributes) . " />\n";
          }
        }
      }
    
      // Add the 'empty' row message if available.
      if (!count($rows) && $empty) {
        $header_count = 0;
        foreach ($header as $header_cell) {
          if (is_array($header_cell)) {
            $header_count += isset($header_cell['colspan']) ? $header_cell['colspan'] : 1;
          }
          else {
            $header_count++;
          }
        }
        $rows[] = array(array('data' => $empty, 'colspan' => $header_count, 'class' => array('empty', 'message')));
      }
    
      $responsive = array();
      // Format the table header:
      if (count($header)) {
        $ts = tablesort_init($header);
        // HTML requires that the thead tag has tr tags in it followed by tbody
        // tags. Using ternary operator to check and see if we have any rows.
        $output .= (count($rows) ? ' <thead><tr>' : ' <tr>');
        $i = 0;
        foreach ($header as $cell) {
          $i++;
          // Track responsive classes for each column as needed. Only the header
          // cells for a column are marked up with the responsive classes by a
          // module developer or themer. The responsive classes on the header cells
          // must be transferred to the content cells.
          if (!empty($cell['class']) && is_array($cell['class'])) {
            if (in_array(RESPONSIVE_PRIORITY_MEDIUM, $cell['class'])) {
              $responsive[$i] =  RESPONSIVE_PRIORITY_MEDIUM;
            }
            elseif (in_array(RESPONSIVE_PRIORITY_LOW, $cell['class'])) {
              $responsive[$i] =  RESPONSIVE_PRIORITY_LOW;
            }
          }
          $cell = tablesort_header($cell, $header, $ts);
          $output .= _theme_table_cell($cell, TRUE);
        }
        // Using ternary operator to close the tags based on whether or not there are rows
        $output .= (count($rows) ? " </tr></thead>\n" : "</tr>\n");
      }
      else {
        $ts = array();
      }
    
      // Format the table rows:
      if (count($rows)) {
        $output .= "<tbody>\n";
        $flip = array('even' => 'odd', 'odd' => 'even');
        $class = 'even';
        foreach ($rows as $number => $row) {
          $attributes = array();
    
          // Check if we're dealing with a simple or complex row
          if (isset($row['data'])) {
            foreach ($row as $key => $value) {
              if ($key == 'data') {
                $cells = $value;
              }
              else {
                $attributes[$key] = $value;
              }
            }
          }
          else {
            $cells = $row;
          }
          if (count($cells)) {
            // Add odd/even class
            if (empty($row['no_striping'])) {
              $class = $flip[$class];
              $attributes['class'][] = $class;
            }
    
            // Build row
            $output .= ' <tr' . new Attribute($attributes) . '>';
            $i = 0;
            foreach ($cells as $cell) {
              $i++;
              // Add active class if needed for sortable tables.
              $cell = tablesort_cell($cell, $header, $ts, $i);
              // Copy RESPONSIVE_PRIORITY_LOW/RESPONSIVE_PRIORITY_MEDIUM
              // class from header to cell as needed.
              if (isset($responsive[$i])) {
                if (is_array($cell)) {
                  $cell['class'][] = $responsive[$i];
                }
                else {
                  $cell = array('data' => $cell, 'class' => $responsive[$i]);
                }
              }
              $output .= _theme_table_cell($cell);
            }
            $output .= " </tr>\n";
          }
        }
        $output .= "</tbody>\n";
      }
    
      $output .= "</table>\n";
      return $output;
    }
    
    /**
     * Returns HTML for a sort icon.
     *
     * @param $variables
     *   An associative array containing:
     *   - style: Set to either 'asc' or 'desc', this determines which icon to show.
     */
    function theme_tablesort_indicator($variables) {
      if ($variables['style'] == "asc") {
        return theme('image', array('uri' => 'core/misc/arrow-asc.png', 'width' => 13, 'height' => 13, 'alt' => t('sort ascending'), 'title' => t('sort ascending')));
      }
      else {
        return theme('image', array('uri' => 'core/misc/arrow-desc.png', 'width' => 13, 'height' => 13, 'alt' => t('sort descending'), 'title' => t('sort descending')));
      }
    }
    
    /**
     * Returns HTML for a marker for new or updated content.
     *
     * @param $variables
     *   An associative array containing:
     *   - type: Number representing the marker type to display. See MARK_NEW,
     *     MARK_UPDATED, MARK_READ.
     */
    function theme_mark($variables) {
      $type = $variables['type'];
      global $user;
      if ($user->uid) {
        if ($type == MARK_NEW) {
          return ' <span class="marker">' . t('new') . '</span>';
        }
        elseif ($type == MARK_UPDATED) {
          return ' <span class="marker">' . t('updated') . '</span>';
        }
      }
    }
    
    /**
     * Preprocesses variables for theme_item_list().
     *
     * @param array $variables
     *   An associative array containing theme variables for theme_item_list().
     *   'items' in variables will be processed to automatically inherit the
     *   variables of this list to any possibly contained nested lists that do not
     *   specify custom render properties. This allows callers to specify larger
     *   nested lists, without having to explicitly specify and repeat the render
     *   properties for all nested child lists.
     */
    function template_preprocess_item_list(&$variables) {
      foreach ($variables['items'] as &$item) {
        // If the item value is an array, then it is a render array.
        if (is_array($item)) {
          // Determine whether there are any child elements in the item that are not
          // fully-specified render arrays. If there are any, then the child
          // elements present nested lists and we automatically inherit the render
          // array properties of the current list to them.
          foreach (element_children($item) as $key) {
            $child = &$item[$key];
            // If this child element does not specify how it can be rendered, then
            // we need to inherit the render properties of the current list.
            if (!isset($child['#type']) && !isset($child['#theme']) && !isset($child['#markup'])) {
              // Since theme_item_list() supports both strings and render arrays as
              // items, the items of the nested list may have been specified as the
              // child elements of the nested list, instead of #items. For
              // convenience, we automatically move them into #items.
              if (!isset($child['#items'])) {
                // This is the same condition as in element_children(), which cannot
                // be used here, since it triggers an error on string values.
                foreach ($child as $child_key => $child_value) {
                  if ($child_key[0] !== '#') {
                    $child['#items'][$child_key] = $child_value;
                    unset($child[$child_key]);
                  }
                }
              }
              // Lastly, inherit the original theme variables of the current list.
              $child['#theme'] = $variables['theme_hook_original'];
              $child['#type'] = $variables['type'];
            }
          }
        }
      }
    }
    
    /**
     * Returns HTML for a list or nested list of items.
     *
     * @param $variables
     *   An associative array containing:
     *   - items: A list of items to render. Allowed values are strings or
     *     render arrays. Render arrays can specify list item attributes in the
     *     #wrapper_attributes property.
     *   - title: The title of the list.
     *   - type: The type of list to return (e.g. "ul", "ol").
     *   - attributes: The attributes applied to the list element.
     */
    function theme_item_list($variables) {
      $items = $variables['items'];
      $title = (string) $variables['title'];
      // @todo 'type' clashes with '#type'. Rename to 'tag'.
      $type = $variables['type'];
      $list_attributes = $variables['attributes'];
    
      $output = '';
      if ($items) {
        $output .= '<' . $type . new Attribute($list_attributes) . '>';
    
        $num_items = count($items);
        $i = 0;
        foreach ($items as &$item) {
          $i++;
          $attributes = array();
          if (is_array($item)) {
            if (isset($item['#wrapper_attributes'])) {
              $attributes = $item['#wrapper_attributes'];
            }
            $item = drupal_render($item);
          }
          $attributes['class'][] = ($i % 2 ? 'odd' : 'even');
          if ($i == 1) {
            $attributes['class'][] = 'first';
          }
          if ($i == $num_items) {
            $attributes['class'][] = 'last';
          }
          $output .= '<li' . new Attribute($attributes) . '>' . $item . '</li>';
        }
        $output .= "</$type>";
      }
    
      // Only output the list container and title, if there are any list items.
      // Check to see whether the block title exists before adding a header.
      // Empty headers are not semantic and present accessibility challenges.
      if ($output !== '') {
        if ($title !== '') {
          $title = '<h3>' . $title . '</h3>';
        }
        $output = '<div class="item-list">' . $title . $output . '</div>';
      }
    
      return $output;
    }
    
    /**
     * Returns HTML for a "more help" link.
     *
     * @param $variables
     *   An associative array containing:
     *   - url: The URL for the link.
     */
    function theme_more_help_link($variables) {
      return '<div class="more-help-link">' . l(t('More help'), $variables['url']) . '</div>';
    }
    
    /**
     * Returns HTML for a feed icon.
     *
     * @param $variables
     *   An associative array containing:
     *   - url: An internal system path or a fully qualified external URL of the
     *     feed.
     *   - title: A descriptive title of the feed.
     */
    function theme_feed_icon($variables) {
      $text = t('Subscribe to !feed-title', array('!feed-title' => $variables['title']));
      if ($image = theme('image', array('uri' => 'core/misc/feed.png', 'width' => 16, 'height' => 16, 'alt' => $text))) {
        return l($image, $variables['url'], array('html' => TRUE, 'attributes' => array('class' => array('feed-icon'), 'title' => $text)));
      }
    }
    
    /**
     * Returns HTML for a generic HTML tag with attributes.
     *
     * @param $variables
     *   An associative array containing:
     *   - element: An associative array describing the tag:
     *     - #tag: The tag name to output. Typical tags added to the HTML HEAD:
     *       - meta: To provide meta information, such as a page refresh.
     *       - link: To refer to stylesheets and other contextual information.
     *       - script: To load JavaScript.
     *     - #attributes: (optional) An array of HTML attributes to apply to the
     *       tag.
     *     - #value: (optional) A string containing tag content, such as inline CSS.
     *     - #value_prefix: (optional) A string to prepend to #value, e.g. a CDATA
     *       wrapper prefix.
     *     - #value_suffix: (optional) A string to append to #value, e.g. a CDATA
     *       wrapper suffix.
     */
    function theme_html_tag($variables) {
      $element = $variables['element'];
      $attributes = isset($element['#attributes']) ? new Attribute($element['#attributes']) : '';
      if (!isset($element['#value'])) {
        return '<' . $element['#tag'] . $attributes . " />\n";
      }
      else {
        $output = '<' . $element['#tag'] . $attributes . '>';
        if (isset($element['#value_prefix'])) {
          $output .= $element['#value_prefix'];
        }
        $output .= $element['#value'];
        if (isset($element['#value_suffix'])) {
          $output .= $element['#value_suffix'];
        }
        $output .= '</' . $element['#tag'] . ">\n";
        return $output;
      }
    }
    
    /**
     * Returns HTML for a "more" link, like those used in blocks.
     *
     * @param $variables
     *   An associative array containing:
     *   - url: The URL of the main page.
     *   - title: A descriptive verb for the link, like 'Read more'.
     */
    function theme_more_link($variables) {
      return '<div class="more-link">' . l(t('More'), $variables['url'], array('attributes' => array('title' => $variables['title']))) . '</div>';
    }
    
    /**
     * Returns HTML for a progress bar.
     *
     * Note that the core Batch API uses this only for non-JavaScript batch jobs.
     *
     * @param $variables
     *   An associative array containing:
     *   - percent: The percentage of the progress.
     *   - message: A string containing information to be displayed.
     */
    function theme_progress_bar($variables) {
      $output = '<div id="progress" class="progress">';
      $output .= '<div class="bar"><div class="filled" style="width: ' . $variables['percent'] . '%"></div></div>';
      $output .= '<div class="percentage">' . $variables['percent'] . '%</div>';
      $output .= '<div class="message">' . $variables['message'] . '</div>';
      $output .= '</div>';
    
      return $output;
    }
    
    /**
     * Returns HTML for a meter.
     *
     * @param $variables
     *   An associative array containing:
     *   - display_value: The textual representation of the meter bar.
     *   - form: A string specifying one or more forms to which the <meter> element
     *     belongs separated by spaces.
     *   - high: A number specifying the range that is considered to be a high
     *     value.
     *   - low: A number specifying the range that is considered to be a low value.
     *   - max: A number specifying the maximum value of the range.
     *   - min: A number specifying the minimum value of the range.
     *   - optimum: A number specifying what value is the optimal value for the
     *     gauge.
     *   - value: A number specifying the current value of the gauge.
     *   - percentage: A number specifying the current percentage of the gauge.
     *   - attributes: Associative array of attributes to be placed in the meter
     *     tag.
     */
    function theme_meter($variables) {
      $attributes = $variables['attributes'];
    
      foreach (array('form', 'high', 'low', 'max', 'min', 'optimum', 'value') as $attribute) {
        if (!empty($variables[$attribute])) {
          // This function was initially designed for the <meter> tag, but due to
          // the lack of browser and styling support for it, we're currently using
          // it's attributes as HTML5 data attributes.
          $attributes['data-' . $attribute] = $variables[$attribute];
        }
      }
    
      $output = '<div' . new Attribute($attributes) . '>';
      $output .= '  <div style="width: '. $variables['percentage'] .'%;" class="foreground"></div>';
      $output .= "</div>\n";
    
      if (!empty($variables['display_value'])) {
        $output .= '<div class="percent">' . $variables['display_value'] . '</div>';
      }
    
      return $output;
    }
    
    /**
     * Returns HTML for an indentation div; used for drag and drop tables.
     *
     * @param $variables
     *   An associative array containing:
     *   - size: Optional. The number of indentations to create.
     */
    function theme_indentation($variables) {
      $output = '';
      for ($n = 0; $n < $variables['size']; $n++) {
        $output .= '<div class="indentation">&nbsp;</div>';
      }
      return $output;
    }
    
    /**
     * @} End of "addtogroup themeable".
     */
    
    /**
     * Returns HTML output for a single table cell for theme_table().
     *
     * @param $cell
     *   Array of cell information, or string to display in cell.
     * @param bool $header
     *   TRUE if this cell is a table header cell, FALSE if it is an ordinary
     *   table cell. If $cell is an array with element 'header' set to TRUE, that
     *   will override the $header parameter.
     *
     * @return
     *   HTML for the cell.
     */
    function _theme_table_cell($cell, $header = FALSE) {
      $attributes = '';
    
      if (is_array($cell)) {
        $data = isset($cell['data']) ? $cell['data'] : '';
        // Cell's data property can be a string or a renderable array.
        if (is_array($data)) {
          $data = drupal_render($data);
        }
        $header |= isset($cell['header']);
        unset($cell['data']);
        unset($cell['header']);
        $attributes = new Attribute($cell);
      }
      else {
        $data = $cell;
      }
    
      if ($header) {
        $output = "<th$attributes>$data</th>";
      }
      else {
        $output = "<td$attributes>$data</td>";
      }
    
      return $output;
    }
    
    /**
     * Adds a default set of helper variables for variable processors and templates.
     *
     * This function is called for theme hooks implemented as templates only, not
     * for theme hooks implemented as functions. This preprocess function is the
     * first in the sequence of preprocessing and processing functions that is
     * called when preparing variables for a template. See theme() for more details
     * about the full sequence.
     *
     * @see theme()
     * @see template_process()
     */
    function template_preprocess(&$variables, $hook) {
      global $user;
      static $count = array(), $default_attributes;
    
      // Track run count for each hook to provide zebra striping.
      // See "template_preprocess_block()" which provides the same feature specific to blocks.
      $count[$hook] = isset($count[$hook]) && is_int($count[$hook]) ? $count[$hook] : 1;
      $variables['zebra'] = ($count[$hook] % 2) ? 'odd' : 'even';
      $variables['id'] = $count[$hook]++;
    
      // Tell all templates where they are located.
      $variables['directory'] = path_to_theme();
    
      // Merge in variables that don't depend on hook and don't change during a
      // single page request.
      // Use the advanced drupal_static() pattern, since this is called very often.
      static $drupal_static_fast;
      if (!isset($drupal_static_fast)) {
        $drupal_static_fast['default_variables'] = &drupal_static(__FUNCTION__);
      }
      $default_variables = &$drupal_static_fast['default_variables'];
      if (!isset($default_variables)) {
        $default_variables = _template_preprocess_default_variables();
      }
      if (!isset($default_attributes)) {
        $default_attributes = new Attribute(array('class' => array()));
      }
      $variables += $default_variables + array(
        'attributes' => clone $default_attributes,
        'title_attributes' => clone $default_attributes,
        'content_attributes' => clone $default_attributes,
      );
    
      // Initialize html class attribute for the current hook.
      $variables['attributes']['class'][] = drupal_html_class($hook);
    }
    
    /**
     * Returns hook-independent variables to template_preprocess().
     */
    function _template_preprocess_default_variables() {
      // Variables that don't depend on a database connection.
      $variables = array(
        'title_prefix' => array(),
        'title_suffix' => array(),
        'db_is_active' => !defined('MAINTENANCE_MODE'),
        // User module overrides these when it is loaded.
        'user' => drupal_anonymous_user(),
        'is_admin' => FALSE,
        'logged_in' => FALSE,
      );
    
      // drupal_is_front_page() might throw an exception.
      try {
        $variables['is_front'] = drupal_is_front_page();
      }
      catch (Exception $e) {
        // If the database is not yet available, set default values for these
        // variables.
        $variables['is_front'] = FALSE;
        $variables['db_is_active'] = FALSE;
      }
    
      // Give modules a chance to alter the default template variables.
      drupal_alter('template_preprocess_default_variables', $variables);
    
      return $variables;
    }
    
    /**
     * Preprocess variables for html.tpl.php
     *
     * @see system_elements()
     * @see html.tpl.php
     */
    function template_preprocess_html(&$variables) {
      $language_interface = language(LANGUAGE_TYPE_INTERFACE);
    
      // Compile a list of classes that are going to be applied to the body element.
      // This allows advanced theming based on context (home page, node of certain type, etc.).
      // Add a class that tells us whether we're on the front page or not.
      $variables['attributes']['class'][] = $variables['is_front'] ? 'front' : 'not-front';
      // Add a class that tells us whether the page is viewed by an authenticated user or not.
      $variables['attributes']['class'][] = $variables['logged_in'] ? 'logged-in' : 'not-logged-in';
    
      // Add information about the number of sidebars.
      if (!empty($variables['page']['sidebar_first']) && !empty($variables['page']['sidebar_second'])) {
        $variables['attributes']['class'][] = 'two-sidebars';
      }
      elseif (!empty($variables['page']['sidebar_first'])) {
        $variables['attributes']['class'][] = 'one-sidebar';
        $variables['attributes']['class'][] = 'sidebar-first';
      }
      elseif (!empty($variables['page']['sidebar_second'])) {
        $variables['attributes']['class'][] = 'one-sidebar';
        $variables['attributes']['class'][] = 'sidebar-second';
      }
      else {
        $variables['attributes']['class'][] = 'no-sidebars';
      }
    
      // Populate the body classes.
      if ($suggestions = theme_get_suggestions(arg(), 'page', '-')) {
        foreach ($suggestions as $suggestion) {
          if ($suggestion != 'page-front') {
            // Add current suggestion to page classes to make it possible to theme
            // the page depending on the current page type (e.g. node, admin, user,
            // etc.) as well as more specific data like node-12 or node-edit.
            $variables['attributes']['class'][] = drupal_html_class($suggestion);
          }
        }
      }
    
      // If on an individual node page, add the node type to body classes.
      if ($node = menu_get_object()) {
        $variables['attributes']['class'][] = drupal_html_class('node-type-' . $node->type);
      }
    
      // Initializes attributes which are specific to the html and body elements.
      $variables['html_attributes'] = new Attribute;
    
      // HTML element attributes.
      $variables['html_attributes']['lang'] = $language_interface->langcode;
      $variables['html_attributes']['dir'] = $language_interface->direction ? 'rtl' : 'ltr';
    
      // Add favicon.
      if (theme_get_setting('toggle_favicon')) {
        $favicon = theme_get_setting('favicon');
        $type = theme_get_setting('favicon_mimetype');
        drupal_add_html_head_link(array('rel' => 'shortcut icon', 'href' => drupal_strip_dangerous_protocols($favicon), 'type' => $type));
      }
    
      $site_config = config('system.site');
      // Construct page title.
      if (drupal_get_title()) {
        $head_title = array(
          'title' => strip_tags(drupal_get_title()),
          'name' => check_plain($site_config->get('name')),
        );
      }
      else {
        $head_title = array('name' => check_plain($site_config->get('name')));
        if ($site_config->get('slogan')) {
          $head_title['slogan'] = strip_tags(filter_xss_admin($site_config->get('slogan')));
        }
      }
      $variables['head_title_array'] = $head_title;
      $variables['head_title'] = implode(' | ', $head_title);
    
      // Display the html.tpl.php's default mobile metatags for responsive design.
      $elements = array(
        'MobileOptimized' => array(
          '#tag' => 'meta',
          '#attributes' => array(
            'name' => 'MobileOptimized',
            'content' => 'width',
          ),
        ),
        'HandheldFriendly' => array(
          '#tag' => 'meta',
          '#attributes' => array(
            'name' => 'HandheldFriendly',
            'content' => 'true',
          ),
        ),
        'viewport' => array(
          '#tag' => 'meta',
          '#attributes' => array(
            'name' => 'viewport',
            'content' => 'width=device-width',
          ),
        ),
        'cleartype' => array(
          '#tag' => 'meta',
          '#attributes' => array(
            'http-equiv' => 'cleartype',
            'content' => 'on',
          ),
        ),
      );
      foreach ($elements as $name => $element) {
        drupal_add_html_head($element, $name);
      }
    
      // Populate the page template suggestions.
      if ($suggestions = theme_get_suggestions(arg(), 'html')) {
        $variables['theme_hook_suggestions'] = $suggestions;
      }
    }
    
    /**
     * Preprocess variables for page.tpl.php
     *
     * Most themes utilize their own copy of page.tpl.php. The default is located
     * inside "modules/system/page.tpl.php". Look in there for the full list of
     * variables.
     *
     * Uses the arg() function to generate a series of page template suggestions
     * based on the current path.
     *
     * Any changes to variables in this preprocessor should also be changed inside
     * template_preprocess_maintenance_page() to keep all of them consistent.
     *
     * @see drupal_render_page()
     * @see template_process_page()
     * @see page.tpl.php
     */
    function template_preprocess_page(&$variables) {
      $language_interface = language(LANGUAGE_TYPE_INTERFACE);
      $site_config = config('system.site');
    
      // Move some variables to the top level for themer convenience and template cleanliness.
      $variables['show_messages'] = $variables['page']['#show_messages'];
    
      foreach (system_region_list($GLOBALS['theme']) as $region_key => $region_name) {
        if (!isset($variables['page'][$region_key])) {
          $variables['page'][$region_key] = array();
        }
      }
    
      // Set up layout variable.
      $variables['layout'] = 'none';
      if (!empty($variables['page']['sidebar_first'])) {
        $variables['layout'] = 'first';
      }
      if (!empty($variables['page']['sidebar_second'])) {
        $variables['layout'] = ($variables['layout'] == 'first') ? 'both' : 'second';
      }
    
      $variables['base_path']         = base_path();
      $variables['front_page']        = url();
      $variables['feed_icons']        = drupal_get_feeds();
      $variables['language']          = $language_interface;
      $variables['language']->dir     = $language_interface->direction ? 'rtl' : 'ltr';
      $variables['logo']              = theme_get_setting('logo');
      $variables['main_menu']         = theme_get_setting('toggle_main_menu') ? menu_main_menu() : array();
      $variables['secondary_menu']    = theme_get_setting('toggle_secondary_menu') ? menu_secondary_menu() : array();
      $variables['action_links']      = menu_local_actions();
      $variables['site_name']         = (theme_get_setting('toggle_name') ? check_plain($site_config->get('name')) : '');
      $variables['site_slogan']       = (theme_get_setting('toggle_slogan') ? filter_xss_admin($site_config->get('slogan')) : '');
      $variables['tabs']              = menu_local_tabs();
    
      if ($node = menu_get_object()) {
        $variables['node'] = $node;
      }
    
      // Populate the page template suggestions.
      if ($suggestions = theme_get_suggestions(arg(), 'page')) {
        $variables['theme_hook_suggestions'] = $suggestions;
      }
    }
    
    /**
     * Process variables for page.tpl.php
     *
     * Perform final addition of variables before passing them into the template.
     * To customize these variables, simply set them in an earlier step.
     *
     * @see template_preprocess_page()
     * @see page.tpl.php
     */
    function template_process_page(&$variables) {
      if (!isset($variables['breadcrumb'])) {
        // Build the breadcrumb last, so as to increase the chance of being able to
        // re-use the cache of an already rendered menu containing the active link
        // for the current page.
        // @see menu_tree_page_data()
        $variables['breadcrumb'] = theme('breadcrumb', array('breadcrumb' => drupal_get_breadcrumb()));
      }
      if (!isset($variables['title'])) {
        $variables['title'] = drupal_get_title();
      }
    
      // Generate messages last in order to capture as many as possible for the
      // current page.
      if (!isset($variables['messages'])) {
        $variables['messages'] = $variables['show_messages'] ? theme('status_messages') : '';
      }
    }
    
    /**
     * Process variables for html.tpl.php
     *
     * Perform final addition and modification of variables before passing into
     * the template. To customize these variables, call drupal_render() on elements
     * in $variables['page'] during THEME_preprocess_page().
     *
     * @see template_preprocess_html()
     * @see html.tpl.php
     */
    function template_process_html(&$variables) {
      drupal_add_library('system', 'html5shiv', TRUE);
      // Render page_top and page_bottom into top level variables.
      $variables['page_top'] = drupal_render($variables['page']['page_top']);
      $variables['page_bottom'] = drupal_render($variables['page']['page_bottom']);
      // Place the rendered HTML for the page body into a top level variable.
      $variables['page']              = $variables['page']['#children'];
      $variables['page_bottom'] .= drupal_get_js('footer');
    
      $variables['head']    = drupal_get_html_head();
      $variables['css']     = drupal_add_css();
      $variables['styles']  = drupal_get_css();
      $variables['scripts'] = drupal_get_js();
    }
    
    /**
     * Generate an array of suggestions from path arguments.
     *
     * This is typically called for adding to the 'theme_hook_suggestions' or
     * 'attributes' class key variables from within preprocess functions, when
     * wanting to base the additional suggestions on the path of the current page.
     *
     * @param $args
     *   An array of path arguments, such as from function arg().
     * @param $base
     *   A string identifying the base 'thing' from which more specific suggestions
     *   are derived. For example, 'page' or 'html'.
     * @param $delimiter
     *   The string used to delimit increasingly specific information. The default
     *   of '__' is appropriate for theme hook suggestions. '-' is appropriate for
     *   extra classes.
     *
     * @return
     *   An array of suggestions, suitable for adding to
     *   $variables['theme_hook_suggestions'] within a preprocess function or to
     *   $variables['attributes']['class'] if the suggestions represent extra CSS classes.
     */
    function theme_get_suggestions($args, $base, $delimiter = '__') {
    
      // Build a list of suggested theme hooks or body classes in order of
      // specificity. One suggestion is made for every element of the current path,
      // though numeric elements are not carried to subsequent suggestions. For
      // example, for $base='page', http://www.example.com/node/1/edit would result
      // in the following suggestions and body classes:
      //
      // page__node              page-node
      // page__node__%           page-node-%
      // page__node__1           page-node-1
      // page__node__edit        page-node-edit
    
      $suggestions = array();
      $prefix = $base;
      foreach ($args as $arg) {
        // Remove slashes or null per SA-CORE-2009-003 and change - (hyphen) to _
        // (underscore).
        //
        // When we discover templates in @see drupal_find_theme_templates,
        // hyphens (-) are converted to underscores (_) before the theme hook
        // is registered. We do this because the hyphens used for delimiters
        // in hook suggestions cannot be used in the function names of the
        // associated preprocess functions. Any page templates designed to be used
        // on paths that contain a hyphen are also registered with these hyphens
        // converted to underscores so here we must convert any hyphens in path
        // arguments to underscores here before fetching theme hook suggestions
        // to ensure the templates are appropriately recognized.
        $arg = str_replace(array("/", "\\", "\0", '-'), array('', '', '', '_'), $arg);
        // The percent acts as a wildcard for numeric arguments since
        // asterisks are not valid filename characters on many filesystems.
        if (is_numeric($arg)) {
          $suggestions[] = $prefix . $delimiter . '%';
        }
        $suggestions[] = $prefix . $delimiter . $arg;
        if (!is_numeric($arg)) {
          $prefix .= $delimiter . $arg;
        }
      }
      if (drupal_is_front_page()) {
        // Front templates should be based on root only, not prefixed arguments.
        $suggestions[] = $base . $delimiter . 'front';
      }
    
      return $suggestions;
    }
    
    /**
     * The variables array generated here is a mirror of template_preprocess_page().
     * This preprocessor will run its course when theme_maintenance_page() is
     * invoked.
     *
     * An alternate template file of "maintenance-page--offline.tpl.php" can be
     * used when the database is offline to hide errors and completely replace the
     * content.
     *
     * The $variables array contains the following arguments:
     * - $content
     *
     * @see maintenance-page.tpl.php
     */
    function template_preprocess_maintenance_page(&$variables) {
      global $theme;
      $language_interface = language(LANGUAGE_TYPE_INTERFACE);
      // Retrieve the theme data to list all available regions.
      $theme_data = list_themes();
      $regions = $theme_data[$theme]->info['regions'];
    
      // Add favicon
      if (theme_get_setting('toggle_favicon')) {
        $favicon = theme_get_setting('favicon');
        $type = theme_get_setting('favicon_mimetype');
        drupal_add_html_head_link(array('rel' => 'shortcut icon', 'href' => drupal_strip_dangerous_protocols($favicon), 'type' => $type));
      }
    
      // Get all region content set with drupal_add_region_content().
      foreach (array_keys($regions) as $region) {
        // Assign region to a region variable.
        $region_content = drupal_get_region_content($region);
        isset($variables[$region]) ? $variables[$region] .= $region_content : $variables[$region] = $region_content;
      }
    
      // Setup layout variable.
      $variables['layout'] = 'none';
      if (!empty($variables['sidebar_first'])) {
        $variables['layout'] = 'first';
      }
      if (!empty($variables['sidebar_second'])) {
        $variables['layout'] = ($variables['layout'] == 'first') ? 'both' : 'second';
      }
    
      $site_config = config('system.site');
      $site_name = $site_config->get('name');
      $site_slogan = $site_config->get('slogan');
    
      // Construct page title
      if (drupal_get_title()) {
        $head_title = array(
          'title' => strip_tags(drupal_get_title()),
          'name' => check_plain($site_name),
        );
      }
      else {
        $head_title = array('name' => check_plain($site_name));
        if ($site_slogan) {
          $head_title['slogan'] = strip_tags(filter_xss_admin($site_slogan));
        }
      }
    
      $variables['head_title_array']  = $head_title;
      $variables['head_title']        = implode(' | ', $head_title);
      $variables['base_path']         = base_path();
      $variables['front_page']        = url();
      $variables['breadcrumb']        = '';
      $variables['feed_icons']        = '';
      $variables['help']              = '';
      $variables['language']          = $language_interface;
      $variables['language']->dir     = $language_interface->direction ? 'rtl' : 'ltr';
      $variables['logo']              = theme_get_setting('logo');
      $variables['messages']          = $variables['show_messages'] ? theme('status_messages') : '';
      $variables['main_menu']         = array();
      $variables['secondary_menu']    = array();
      $variables['site_name']         = (theme_get_setting('toggle_name') ? check_plain($site_name) : '');
      $variables['site_slogan']       = (theme_get_setting('toggle_slogan') ? filter_xss_admin($site_slogan) : '');
      $variables['tabs']              = '';
      $variables['title']             = drupal_get_title();
    
      // Compile a list of classes that are going to be applied to the body element.
      $variables['attributes']['class'][] = 'in-maintenance';
      if (isset($variables['db_is_active']) && !$variables['db_is_active']) {
        $variables['attributes']['class'][] = 'db-offline';
      }
      if ($variables['layout'] == 'both') {
        $variables['attributes']['class'][] = 'two-sidebars';
      }
      elseif ($variables['layout'] == 'none') {
        $variables['attributes']['class'][] = 'no-sidebars';
      }
      else {
        $variables['attributes']['class'][] = 'one-sidebar';
        $variables['attributes']['class'][] = 'sidebar-' . $variables['layout'];
      }
    
      // Dead databases will show error messages so supplying this template will
      // allow themers to override the page and the content completely.
      if (isset($variables['db_is_active']) && !$variables['db_is_active']) {
        $variables['theme_hook_suggestion'] = 'maintenance_page__offline';
      }
    }
    
    /**
     * The variables array generated here is a mirror of template_process_html().
     * This processor will run its course when theme_maintenance_page() is invoked.
     *
     * @see maintenance-page.tpl.php
     */
    function template_process_maintenance_page(&$variables) {
      $variables['head']    = drupal_get_html_head();
      $variables['css']     = drupal_add_css();
      $variables['styles']  = drupal_get_css();
      $variables['scripts'] = drupal_get_js();
    }
    
    /**
     * Preprocess variables for region.tpl.php
     *
     * Prepare the values passed to the theme_region function to be passed into a
     * pluggable template engine. Uses the region name to generate a template file
     * suggestions. If none are found, the default region.tpl.php is used.
     *
     * @see drupal_region_class()
     * @see region.tpl.php
     */
    function template_preprocess_region(&$variables) {
      // Create the $content variable that templates expect.
      $variables['content'] = $variables['elements']['#children'];
      $variables['region'] = $variables['elements']['#region'];
    
      $variables['attributes']['class'][] = drupal_region_class($variables['region']);
      $variables['theme_hook_suggestions'][] = 'region__' . $variables['region'];
    }
    
    /**
     * Provides theme registration for themes across .inc files.
     */
    function drupal_common_theme() {
      return array(
        // From theme.inc.
        'html' => array(
          'render element' => 'page',
          'template' => 'html',
        ),
        'page' => array(
          'render element' => 'page',
          'template' => 'page',
        ),
        'region' => array(
          'render element' => 'elements',
          'template' => 'region',
        ),
        'datetime' => array(
          'variables' => array('timestamp' => NULL, 'text' => NULL, 'attributes' => array(), 'html' => FALSE),
          'template' => 'datetime',
        ),
        'status_messages' => array(
          'variables' => array('display' => NULL),
        ),
        'link' => array(
          'variables' => array('text' => NULL, 'path' => NULL, 'options' => array()),
        ),
        'links' => array(
          'variables' => array('links' => array(), 'attributes' => array('class' => array('links')), 'heading' => array()),
        ),
        'dropbutton_wrapper' => array(
          'render element' => 'element',
        ),
        'image' => array(
          // HTML 4 and XHTML 1.0 always require an alt attribute. The HTML 5 draft
          // allows the alt attribute to be omitted in some cases. Therefore,
          // default the alt attribute to an empty string, but allow code calling
          // theme('image') to pass explicit NULL for it to be omitted. Usually,
          // neither omission nor an empty string satisfies accessibility
          // requirements, so it is strongly encouraged for code calling
          // theme('image') to pass a meaningful value for the alt variable.
          // - http://www.w3.org/TR/REC-html40/struct/objects.html#h-13.8
          // - http://www.w3.org/TR/xhtml1/dtds.html
          // - http://dev.w3.org/html5/spec/Overview.html#alt
          // The title attribute is optional in all cases, so it is omitted by
          // default.
          'variables' => array('uri' => NULL, 'width' => NULL, 'height' => NULL, 'alt' => '', 'title' => NULL, 'attributes' => array()),
        ),
        'breadcrumb' => array(
          'variables' => array('breadcrumb' => NULL),
        ),
        'help' => array(
          'variables' => array(),
        ),
        'table' => array(
          'variables' => array('header' => NULL, 'rows' => NULL, 'attributes' => array(), 'caption' => NULL, 'colgroups' => array(), 'sticky' => TRUE, 'responsive' => TRUE, 'empty' => ''),
        ),
        'meter' => array(
          'variables' => array('display_value' => NULL, 'form' => NULL, 'high' => NULL, 'low' => NULL, 'max' => NULL, 'min' => NULL, 'optimum' => NULL, 'value' => NULL, 'percentage' => NULL, 'attributes' => array()),
        ),
        'tablesort_indicator' => array(
          'variables' => array('style' => NULL),
        ),
        'mark' => array(
          'variables' => array('type' => MARK_NEW),
        ),
        'item_list' => array(
          'variables' => array('items' => array(), 'title' => '', 'type' => 'ul', 'attributes' => array()),
        ),
        'more_help_link' => array(
          'variables' => array('url' => NULL),
        ),
        'feed_icon' => array(
          'variables' => array('url' => NULL, 'title' => NULL),
        ),
        'more_link' => array(
          'variables' => array('url' => NULL, 'title' => NULL)
        ),
        'progress_bar' => array(
          'variables' => array('percent' => NULL, 'message' => NULL),
        ),
        'indentation' => array(
          'variables' => array('size' => 1),
        ),
        'html_tag' => array(
          'render element' => 'element',
        ),
        // From theme.maintenance.inc.
        'maintenance_page' => array(
          'variables' => array('content' => NULL, 'show_messages' => TRUE),
          'template' => 'maintenance-page',
        ),
        'update_page' => array(
          'variables' => array('content' => NULL, 'show_messages' => TRUE),
        ),
        'install_page' => array(
          'variables' => array('content' => NULL),
        ),
        'task_list' => array(
          'variables' => array('items' => NULL, 'active' => NULL),
        ),
        'authorize_message' => array(
          'variables' => array('message' => NULL, 'success' => TRUE),
        ),
        'authorize_report' => array(
          'variables' => array('messages' => array()),
        ),
        // From pager.inc.
        'pager' => array(
          'variables' => array('tags' => array(), 'element' => 0, 'parameters' => array(), 'quantity' => 9),
        ),
        'pager_first' => array(
          'variables' => array('text' => NULL, 'element' => 0, 'parameters' => array()),
        ),
        'pager_previous' => array(
          'variables' => array('text' => NULL, 'element' => 0, 'interval' => 1, 'parameters' => array()),
        ),
        'pager_next' => array(
          'variables' => array('text' => NULL, 'element' => 0, 'interval' => 1, 'parameters' => array()),
        ),
        'pager_last' => array(
          'variables' => array('text' => NULL, 'element' => 0, 'parameters' => array()),
        ),
        'pager_link' => array(
          'variables' => array('text' => NULL, 'page_new' => NULL, 'element' => NULL, 'parameters' => array(), 'attributes' => array()),
        ),
        // From menu.inc.
        'menu_link' => array(
          'render element' => 'element',
        ),
        'menu_tree' => array(
          'render element' => 'tree',
        ),
        'menu_local_task' => array(
          'render element' => 'element',
        ),
        'menu_local_action' => array(
          'render element' => 'element',
        ),
        'menu_local_tasks' => array(
          'variables' => array('primary' => array(), 'secondary' => array()),
        ),
        // From form.inc.
        'select' => array(
          'render element' => 'element',
        ),
        'fieldset' => array(
          'render element' => 'element',
        ),
        'radio' => array(
          'render element' => 'element',
        ),
        'radios' => array(
          'render element' => 'element',
        ),
        'date' => array(
          'render element' => 'element',
        ),
        'exposed_filters' => array(
          'render element' => 'form',
        ),
        'checkbox' => array(
          'render element' => 'element',
        ),
        'checkboxes' => array(
          'render element' => 'element',
        ),
        'button' => array(
          'render element' => 'element',
        ),
        'image_button' => array(
          'render element' => 'element',
        ),
        'hidden' => array(
          'render element' => 'element',
        ),
        'textfield' => array(
          'render element' => 'element',
        ),
        'tel' => array(
          'render element' => 'element',
        ),
        'email' => array(
          'render element' => 'element',
        ),
        'url' => array(
          'render element' => 'element',
        ),
        'number' => array(
          'render element' => 'element',
        ),
        'range' => array(
          'render element' => 'element',
        ),
        'color' => array(
          'render element' => 'element',
        ),
        'form' => array(
          'render element' => 'element',
        ),
        'textarea' => array(
          'render element' => 'element',
        ),
        'search' => array(
          'render element' => 'element',
        ),
        'password' => array(
          'render element' => 'element',
        ),
        'file' => array(
          'render element' => 'element',
        ),
        'tableselect' => array(
          'render element' => 'element',
        ),
        'form_element' => array(
          'render element' => 'element',
        ),
        'form_required_marker' => array(
          'render element' => 'element',
        ),
        'form_element_label' => array(
          'render element' => 'element',
        ),
        'vertical_tabs' => array(
          'render element' => 'element',
        ),
        'container' => array(
          'render element' => 'element',
        ),
      );
    }