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node.api.php

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    theme.inc 86.20 KiB
    <?php
    // $Id$
    
    /**
     * @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.
     *
     * @ingroup themeable
     */
    
    /**
     * @name Content markers
     * @{
     * Markers used by theme_mark() and node_mark() to designate content.
     * @see theme_mark(), node_mark()
     */
    
    /**
     * Mark content as read.
     */
    define('MARK_READ', 0);
    
    /**
     * Mark content as being new.
     */
    define('MARK_NEW', 1);
    
    /**
     * Mark content as being updated.
     */
    define('MARK_UPDATED', 2);
    
    /**
     * @} End of "Content markers".
     */
    
    /**
     * Determines if a theme is available to use.
     *
     * @param $theme
     *   An object representing the theme to check.
     * @return
     *   Boolean TRUE if the theme is enabled or is the site administration theme;
     *   FALSE otherwise.
     */
    function drupal_theme_access($theme) {
      $admin_theme = variable_get('admin_theme');
      return !empty($theme->status) || ($admin_theme && $theme->name == $admin_theme);
    }
    
    /**
     * 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) && isset($themes[$user->theme]) && drupal_theme_access($themes[$user->theme]) ? $user->theme : variable_get('theme_default', 'garland');
    
      // Allow modules to override the present theme... only select custom theme
      // if it is available in the list of themes that can be accessed.
      $custom_theme = menu_get_custom_theme();
      $theme = $custom_theme && isset($themes[$custom_theme]) && drupal_theme_access($themes[$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)) {
        $base_theme[] = $new_base_theme = $themes[$themes[$ancestor]->base_theme];
        $ancestor = $themes[$ancestor]->base_theme;
      }
      _drupal_theme_initialize($themes[$theme], array_reverse($base_theme));
    }
    
    /**
     * 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('weight' => CSS_THEME, '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('weight' => JS_THEME));
      }
    
      $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;
        }
      }
    
      if (function_exists($registry_callback)) {
        $registry_callback($theme, $base_theme, $theme_engine);
      }
    }
    
    /**
     * Get the theme registry.
     * @return
     *   The theme registry array if it has been stored in memory, NULL otherwise.
     */
    function theme_get_registry() {
      return _theme_set_registry();
    }
    
    /**
     * Store the theme registry in memory.
     * @param $registry
     *   A registry array as returned by _theme_build_registry()
     * @return
     *   The theme registry array stored in memory
     */
    function _theme_set_registry($registry = NULL) {
      static $theme_registry = NULL;
    
      if (isset($registry)) {
        $theme_registry = $registry;
      }
    
      return $theme_registry;
    }
    
    /**
     * Get the theme_registry cache from the database; 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 $theme objects representing the ancestor themes in
     *   oldest first order.
     * @param theme_engine
     *   The name of the theme engine.
     */
    function _theme_load_registry($theme, $base_theme = NULL, $theme_engine = NULL) {
      // Check the theme registry cache; if it exists, use it.
      $cache = cache_get("theme_registry:$theme->name", 'cache');
      if (isset($cache->data)) {
        $registry = $cache->data;
        _theme_set_registry($registry);
      }
      else {
        // If not, build one and cache it.
        $registry = _theme_build_registry($theme, $base_theme, $theme_engine);
       // Only persist this registry if all modules are loaded. This assures a 
       // complete set of theme hooks.
        if (drupal_get_bootstrap_phase() == DRUPAL_BOOTSTRAP_FULL) {
          _theme_save_registry($theme, $registry);
          _theme_set_registry($registry);
        }
      }
    }
    
    /**
     * Write the theme_registry cache into the database.
     */
    function _theme_save_registry($theme, $registry) {
      cache_set("theme_registry:$theme->name", $registry);
    }
    
    /**
     * 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() {
      cache_clear_all('theme_registry', 'cache', 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.
     *   - 'arguments': The arguments for this theme hook as defined in
     *     hook_theme(). If there is more than one implementation and 'arguments' is
     *     not specified in a later one, then the previous definition is kept.
     *   - 'theme paths': The paths where implementations of a theme hook can be
     *     found. Its definition is similarly inherited like 'arguments'. Each time
     *     _theme_process_registry() is called for this theme hook, either the
     *     'path' key from hook_theme() (if defined) or $path is added.
     *   - '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 $name is. For example, modules/system or
     *   themes/garland.
     *
     * @see theme()
     * @see _theme_process_registry()
     * @see hook_theme()
     * @see list_themes()
     */
    function _theme_process_registry(&$cache, $name, $type, $theme, $path) {
      $result = array();
      $function = $name . '_theme';
    
      // 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',
      );
    
      if (function_exists($function)) {
        $result = $function($cache, $type, $theme, $path);
        foreach ($result as $hook => $info) {
          $result[$hook]['type'] = $type;
          $result[$hook]['theme path'] = $path;
          // if function and file are left out, default to standard naming
          // conventions.
          if (!isset($info['template']) && !isset($info['function'])) {
            $result[$hook]['function'] = ($type == 'module' ? 'theme_' : $name . '_') . $hook;
          }
          // If a path is set in the info, use what was set. Otherwise use the
          // default path. This is mostly so system.module can declare theme
          // functions on behalf of core .include files.
          // All files are included to be safe. Conditionally included
          // files can prevent them from getting registered.
          if (isset($cache[$hook]['includes'])) {
            $result[$hook]['includes'] = $cache[$hook]['includes'];
          }
          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 'arguments' have been defined previously, carry them forward.
          // This should happen if a theme overrides a Drupal defined theme
          // function, for example.
          if (!isset($info['arguments']) && isset($cache[$hook])) {
            $result[$hook]['arguments'] = $cache[$hook]['arguments'];
          }
    
          // 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 . '/' . $info['template'];
            }
    
            // These are used for template naming suggestions. Theme implementations
            // can occur in multiple paths. Suggestions should follow.
            if (!isset($info['theme paths']) && isset($cache[$hook])) {
              $result[$hook]['theme paths'] = $cache[$hook]['theme paths'];
            }
            // Check for sub-directories.
            $result[$hook]['theme paths'][] = isset($info['path']) ? $info['path'] : $path;
          }
    
          // 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.
        $cache = array_merge($cache, $result);
      }
    
      // 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;
              }
              // Ensure uniqueness.
              $cache[$hook][$phase_key] = array_unique($cache[$hook][$phase_key]);
            }
          }
        }
      }
    }
    
    /**
     * Rebuild 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.
      foreach (module_implements('theme') as $module) {
        _theme_process_registry($cache, $module, 'module', $module, drupal_get_path('module', $module));
      }
    
      // 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 $refresh
     *   Whether to reload the list of themes from the database. Defaults to FALSE.
     * @return
     *   An associative array of the currently available themes. The keys are the
     *   names of the themes and the values are objects having the following
     *   properties:
     *   - 'filename': The name of the .info file.
     *   - 'name': The name of the theme.
     *   - 'status': 1 for enabled, 0 for disabled themes.
     *   - 'info': The contents of the .info file.
     *   - 'stylesheets': A two dimensional array, using the first key for the
     *     'media' attribute (e.g. 'all'), the second for the name of the file
     *     (e.g. style.css). The value is a complete filepath
     *     (e.g. themes/garland/style.css).
     *   - 'scripts': An associative array of JavaScripts, using the filename as key
     *     and the complete filepath as value.
     *   - 'engine': The name of the theme engine.
     *   - 'base theme': The name of the base theme.
     */
    function list_themes($refresh = FALSE) {
      static $list = array();
    
      if ($refresh) {
        $list = array();
      }
    
      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 (db_is_active() && !defined('MAINTENANCE_MODE')) {
          $result = db_query("SELECT * FROM {system} WHERE type = :theme", array(':theme' => 'theme'));
          foreach ($result as $theme) {
            if (file_exists($theme->filename)) {
              $theme->info = unserialize($theme->info);
              $themes[] = $theme;
            }
          }
        }
        else {
          // Scan the installation when the database should not be read.
          $themes = _system_get_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 => $path) {
            if (file_exists($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;
    }
    
    /**
     * Generate the themed output.
     *
     * All requests for theme hooks must go through this function. It examines
     * the request and routes it to the appropriate theme function. The theme
     * registry is checked to determine which implementation to use, which may
     * be a function or a template.
     *
     * If the implementation is a template, the arguments are converted to a
     * $variables array. This array is then modified by the module implementing
     * the hook, theme engine (if applicable) and the theme. The following
     * functions may be used to modify the $variables array. They are processed in
     * two distinct phases; "preprocess" and "process" functions. The order it is
     * listed here is the order in which it will execute.
     *
     * - template_preprocess(&$variables)
     *   This sets a default set of variables for all template implementations.
     *
     * - template_preprocess_HOOK(&$variables)
     *   This is the first preprocessor called specific to the hook; it should be
     *   implemented by the module that registers it.
     *
     * - MODULE_preprocess(&$variables)
     *   This will be called for all templates; it should only be used if there
     *   is a real need. It's purpose is similar to template_preprocess().
     *
     * - MODULE_preprocess_HOOK(&$variables)
     *   This is for modules that want to alter or provide extra variables for
     *   theming hooks not registered to itself. For example, if a module named
     *   "foo" wanted to alter the $classes_array variable for the hook "node" a
     *   preprocess function of foo_preprocess_node() can be created to intercept
     *   and alter the variable.
     *
     * - ENGINE_engine_preprocess(&$variables)
     *   This function should only be implemented by theme engines and exists
     *   so that it can set necessary variables for all hooks.
     *
     * - ENGINE_engine_preprocess_HOOK(&$variables)
     *   This is the same as the previous function, but it is called for a single
     *   theming hook.
     *
     * - THEME_preprocess(&$variables)
     *   This is for themes that want to alter or provide extra variables. For
     *   example, if a theme named "foo" wanted to alter the $classes_array variable
     *   for the hook "node" a preprocess function of foo_preprocess_node() can be
     *   created to intercept and alter the variable.
     *
     * - THEME_preprocess_HOOK(&$variables)
     *   The same applies from the previous function, but it is called for a
     *   specific hook.
     *
     * - template_process(&$variables)
     *   This sets a default set of variables for all template implementations.
     *
     * - template_process_HOOK(&$variables)
     *   This is the first processor called specific to the hook; it should be
     *   implemented by the module that registers it.
     *
     * - MODULE_process(&$variables)
     *   This will be called for all templates; it should only be used if there
     *   is a real need. It's purpose is similar to template_process().
     *
     * - MODULE_process_HOOK(&$variables)
     *   This is for modules that want to alter or provide extra variables for
     *   theming hooks not registered to itself. For example, if a module named
     *   "foo" wanted to alter the $classes_array variable for the hook "node" a
     *   process function of foo_process_node() can be created to intercept
     *   and alter the variable.
     *
     * - ENGINE_engine_process(&$variables)
     *   This function should only be implemented by theme engines and exists
     *   so that it can set necessary variables for all hooks.
     *
     * - ENGINE_engine_process_HOOK(&$variables)
     *   This is the same as the previous function, but it is called for a single
     *   theming hook.
     *
     * - ENGINE_process(&$variables)
     *   This is meant to be used by themes that utilize a theme engine. It is
     *   provided so that the processor is not locked into a specific theme.
     *   This makes it easy to share and transport code but theme authors must be
     *   careful to prevent fatal re-declaration errors when using sub-themes that
     *   have their own processor named exactly the same as its base theme. In
     *   the default theme engine (PHPTemplate), sub-themes will load their own
     *   template.php file in addition to the one used for its parent theme. This
     *   increases the risk for these errors. A good practice is to use the engine
     *   name for the base theme and the theme name for the sub-themes to minimize
     *   this possibility.
     *
     * - ENGINE_process_HOOK(&$variables)
     *   The same applies from the previous function, but it is called for a
     *   specific hook.
     *
     * - THEME_process(&$variables)
     *   These functions are based upon the raw theme; they should primarily be
     *   used by themes that do not use an engine or by sub-themes. It serves the
     *   same purpose as ENGINE_process().
     *
     * - THEME_process_HOOK(&$variables)
     *   The same applies from the previous function, but it is called for a
     *   specific hook.
     *
     * If the implementation is a function, only the hook-specific preprocess
     * and process functions (the ones ending in _HOOK) are called from the
     * above list. There are two reasons why the non-hook-specific preprocess
     * and process functions (the ones not ending in _HOOK) are not called for
     * function-implemented theme hooks:
     *
     * - Function-implemented theme hooks need to be fast, and calling the
     *   non-hook-specific preprocess and process functions on them would incur
     *   a noticeable performance penalty.
     *
     * - Function-implemented theme hooks can only make use of variables
     *   declared as arguments within the hook_theme() function that registers
     *   the theme hook, and cannot make use of additional generic variables.
     *   For the most part, non-hook-specific preprocess and process functions
     *   add/modify variables other than the theme hook's arguments, variables
     *   that are potentially useful in template files, but unavailable to
     *   function implementations.
     *
     * For template-implemented theme hooks, there are two special variables that
     * these preprocess and process functions can set:
     *   'template_file' and 'template_files'. These will be merged together
     *   to form a list of 'suggested' alternate template files to use, in
     *   reverse order of priority. template_file will always be a higher
     *   priority than items in template_files. theme() will then look for these
     *   files, one at a time, and use the first one that exists. If none exists,
     *   theme() will use the original registered file for the theme hook.
     *
     * For function-implemented theme hooks, there are two special variables that
     * these preprocess and process functions can set:
     *   'theme_function' and 'theme_functions'. These will be merged together
     *   to form a list of 'suggested' alternate functions to use, in
     *   reverse order of priority. theme_function will always be a higher
     *   priority than items in theme_functions. theme() will then call the
     *   highest priority function that exists. If none exists, theme() will call
     *   the original registered function for the theme hook.
     *
     * @param $hook
     *   The name of the theme function to call. May be an array, in which
     *   case the first hook that actually has an implementation registered
     *   will be used. This can be used to choose 'fallback' theme implementations,
     *   so that if the specific theme hook isn't implemented anywhere, a more
     *   generic one will be used. This can allow themes to create specific theme
     *   implementations for named objects.
     * @param ...
     *   Additional arguments to pass along to the theme function.
     * @return
     *   An HTML string that generates the themed output.
     */
    function theme() {
      $args = func_get_args();
      $hook = array_shift($args);
    
      static $hooks = NULL;
      if (!isset($hooks)) {
        drupal_theme_initialize();
        $hooks = theme_get_registry();
      }
    
      if (is_array($hook)) {
        foreach ($hook as $candidate) {
          if (isset($hooks[$candidate])) {
            break;
          }
        }
        $hook = $candidate;
      }
    
      if (!isset($hooks[$hook])) {
        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 . '/' . $include_file;
        }
      }
      if (isset($info['function'])) {
        // The theme call is a function.
    
        // If a theme function that does not expect a renderable array is called
        // with a renderable array as the only argument (via drupal_render), then
        // we take the arguments from the properties of the renderable array. If
        // missing, use hook_theme() defaults.
        if (isset($args[0]) && is_array($args[0]) && isset($args[0]['#theme']) && count($info['arguments']) > 1) {
          $new_args = array();
          foreach ($info['arguments'] as $name => $default) {
            $new_args[] = isset($args[0]["#$name"]) ? $args[0]["#$name"] : $default;
          }
          $args = $new_args;
        }
    
        // Invoke the variable processors, if any.
        // We minimize the overhead for theming hooks that have no processors and
        // are called many times per page request by caching '_no_processors'. If
        // we do have processors, then the overhead of calling them overshadows the
        // overhead of calling empty().
        if (!isset($info['_no_processors'])) {
          if (!empty($info['preprocess functions']) || !empty($info['process functions'])) {
            $variables = array(
              'theme_functions' => array(),
            );
            if (!empty($info['arguments'])) {
              $count = 0;
              foreach ($info['arguments'] as $name => $default) {
                $variables[$name] = isset($args[$count]) ? $args[$count] : $default;
                $count++;
              }
            }
            // We don't want a poorly behaved process function changing $hook.
            $hook_clone = $hook;
            foreach (array('preprocess functions', 'process functions') as $phase) {
              if (!empty($info[$phase])) {
                foreach ($info[$phase] as $processor_function) {
                  if (function_exists($processor_function)) {
                    $processor_function($variables, $hook_clone);
                  }
                }
              }
            }
            if (!empty($info['arguments'])) {
              $count = 0;
              foreach ($info['arguments'] as $name => $default) {
                $args[$count] = $variables[$name];
                $count++;
              }
            }
    
            // Get suggestions for alternate functions out of the variables that
            // were set. This lets us dynamically choose a function from a list.
            // The order is FILO, so this array is ordered from least appropriate
            // functions to most appropriate last.
            $suggestions = array();
            if (isset($variables['theme_functions'])) {
              $suggestions = $variables['theme_functions'];
            }
            if (isset($variables['theme_function'])) {
              $suggestions[] = $variables['theme_function'];
            }
            foreach (array_reverse($suggestions) as $suggestion) {
              if (function_exists($suggestion)) {
                $info['function'] = $suggestion;
                break;
              }
            }
          }
          else {
            $hooks[$hook]['_no_processors'] = TRUE;
          }
        }
    
        // Call the function.
        if (function_exists($info['function'])) {
          $output = call_user_func_array($info['function'], $args);
        }
      }
      else {
        // The theme call is a template.
        $variables = array(
          'template_files' => array()
        );
        if (!empty($info['arguments'])) {
          $count = 0;
          foreach ($info['arguments'] as $name => $default) {
            $variables[$name] = isset($args[$count]) ? $args[$count] : $default;
            $count++;
          }
        }
    
        // default render function and extension.
        $render_function = 'theme_render_template';
        $extension = '.tpl.php';
    
        // Run through the theme engine variables, if necessary
        global $theme_engine;
        if (isset($theme_engine)) {
          // If theme or theme engine is implementing this, it may have
          // a different extension and a different renderer.
          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();
            }
          }
        }
    
        // This construct ensures that we can keep a reference through
        // call_user_func_array.
        $args = array(&$variables, $hook);
        foreach (array('preprocess functions', 'process functions') as $phase) {
          if (!empty($info[$phase])) {
            foreach ($info[$phase] as $processor_function) {
              if (function_exists($processor_function)) {
                call_user_func_array($processor_function, $args);
              }
            }
          }
        }
    
        // Get suggestions for alternate templates out of the variables
        // that were set. This lets us dynamically choose a template
        // from a list. The order is FILO, so this array is ordered from
        // least appropriate first to most appropriate last.
        $suggestions = array();
    
        if (isset($variables['template_files'])) {
          $suggestions = $variables['template_files'];
        }
        if (isset($variables['template_file'])) {
          $suggestions[] = $variables['template_file'];
        }
    
        if ($suggestions) {
          $template_file = drupal_discover_template($info['theme paths'], $suggestions, $extension);
        }
    
        if (empty($template_file)) {
          $template_file = $info['template'] . $extension;
          if (isset($info['path'])) {
            $template_file = $info['path'] . '/' . $template_file;
          }
        }
        $output = $render_function($template_file, $variables);
      }
      // restore path_to_theme()
      $theme_path = $temp;
      return $output;
    }
    
    /**
     * Determine and return which template file will generate the output.
     *
     * This helper allows the theme system to pick the template at runtime instead
     * of build time.
     *
     * @see template_page_suggestions()
     * @see template_preprocess_block()
     *
     * @param $paths
     *   The paths where templates can be found. See _theme_process_registry()
     *   'theme paths' for more information.
     * @param $suggestions
     *   The possible template names. These are derived from
     *   $variables['template_files'] and $variables['template_file], defined by
     *   preprocess functions. Each file is checked on every path in the order of
     *   precedence defined by theme().
     * @return
     *   The filepath to the template that will generate the output. If none is
     *   found, then theme() will use the 'template' as set by
     *   _theme_process_registry().
     *
     * @see _theme_process_registry()
     * @see theme()
     */
    function drupal_discover_template($paths, $suggestions, $extension = '.tpl.php') {
      global $theme_engine;
    
      // Remove slashes or null to prevent files from being included from
      // an unexpected location (especially on Windows servers).
      $extension = str_replace(array("/", "\\", "\0"), '', $extension);
    
      // Loop through all paths and suggestions in FIFO order.
      $suggestions = array_reverse($suggestions);
      $paths = array_reverse($paths);
      foreach ($suggestions as $suggestion) {
        if (!empty($suggestion)) {
          $suggestion = str_replace(array("/", "\\", "\0"), '', $suggestion);
          foreach ($paths as $path) {
            if (file_exists($file = $path . '/' . $suggestion . $extension)) {
              return $file;
            }
          }
        }
      }
    }
    
    /**
     * 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;
    }
    
    /**
     * Find overridden theme functions. Called by themes and/or theme engines to
     * easily discover 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 $templates
     *   The functions found, suitable for returning from hook_theme;
     */
    function drupal_find_theme_functions($cache, $prefixes) {
      $templates = array();
      $functions = get_defined_functions();
    
      foreach ($cache as $hook => $info) {
        foreach ($prefixes as $prefix) {
          if (!empty($info['pattern'])) {
            $matches = preg_grep('/^' . $prefix . '_' . $info['pattern'] . '/', $functions['user']);
            if ($matches) {
              foreach ($matches as $match) {
                $new_hook = str_replace($prefix . '_', '', $match);
                $templates[$new_hook] = array(
                  'function' => $match,
                  'arguments' => $info['arguments'],
                );
              }
            }
          }
          if (function_exists($prefix . '_' . $hook)) {
            $templates[$hook] = array(
              'function' => $prefix . '_' . $hook,
            );
            // Ensure that the pattern is maintained from base themes to its sub-themes.
            // Each sub-theme will have their functions scanned so the pattern must be
            // held for subsequent runs.
            if (isset($info['pattern'])) {
              $templates[$hook]['pattern'] = $info['pattern'];
            }
          }
        }
      }
    
      return $templates;
    }
    
    /**
     * Find overridden theme templates. Called by themes and/or theme engines to
     * easily discover 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) {
      $templates = 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('.', '\.', $extension) . '$/';
      // Because drupal_system_listing works the way it does, we check for real
      // templates separately from checking for patterns.
      $files = drupal_system_listing($regex, $path, 'name', 0);
      foreach ($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 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($template, '.')) !== 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])) {
          $templates[$hook] = array(
            'template' => $template,
            'path' => dirname($file->uri),
          );
        }
        // Ensure that the pattern is maintained from base themes to its sub-themes.
        // Each sub-theme will have their templates scanned so the pattern must be
        // held for subsequent runs.
        if (isset($cache[$hook]['pattern'])) {
          $templates[$hook]['pattern'] = $cache[$hook]['pattern'];
        }
      }
    
      $patterns = array_keys($files);
    
      foreach ($cache as $hook => $info) {
        if (!empty($info['pattern'])) {
          // Transform _ in pattern to - to match file naming scheme
          // for the purposes of searching.
          $pattern = strtr($info['pattern'], '_', '-');
    
          $matches = preg_grep('/^' . $pattern . '/', $patterns);
          if ($matches) {
            foreach ($matches as $match) {
              $file = substr($match, 0, strpos($match, '.'));
              // Put the underscores back in for the hook name and register this pattern.
              $templates[strtr($file, '-', '_')] = array(
                'template' => $file,
                'path' => dirname($files[$match]->uri),
                'arguments' => $info['arguments'],
              );
            }
          }
        }
      }
      return $templates;
    }
    
    /**
     * Retrieve an associative array containing the settings for a theme.
     *
     * The final settings are arrived at by merging the default settings,
     * the site-wide settings, and the settings defined for the specific theme.
     * If no $key was specified, only the site-wide theme defaults are retrieved.
     *
     * The default values for each of settings are also defined in this function.
     * To add new settings, add their default values here, and then add form elements
     * to system_theme_settings() in system.module.
     *
     * @param $key
     *  The template/style value for a given theme.
     *
     * @return
     *   An associative array containing theme settings.
     */
    function theme_get_settings($key = NULL) {
      $defaults = 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',
        'main_menu'                        =>  1,
        'secondary_menu'                   =>  1,
        'toggle_logo'                      =>  1,
        'toggle_favicon'                   =>  1,
        'toggle_name'                      =>  1,
        'toggle_search'                    =>  0,
        'toggle_slogan'                    =>  0,
        'toggle_node_user_picture'         =>  0,
        'toggle_comment_user_picture'      =>  0,
        'toggle_comment_user_verification' =>  1,
        'toggle_main_menu'                 =>  1,
        'toggle_secondary_menu'            =>  1,
      );
    
      $settings = array_merge($defaults, variable_get('theme_settings', array()));
    
      if ($key) {
        $settings = array_merge($settings, variable_get(str_replace('/', '_', 'theme_' . $key . '_settings'), array()));
      }
    
      // Only offer search box if search.module is enabled.
      if (!defined('MAINTENANCE_MODE') && module_exists('search') && user_access('search content')) {
        $settings['toggle_search'] = 1;
      }
    
      return $settings;
    }
    
    /**
     * Retrieve a setting for the current theme.
     * This function is designed for use from within themes & engines
     * to determine theme settings made in the admin interface.
     *
     * Caches values for speed (use $refresh = TRUE to refresh cache)
     *
     * @param $setting_name
     *  The name of the setting to be retrieved.
     *
     * @param $refresh
     *  Whether to reload the cache of settings.
     *
     * @return
     *   The value of the requested setting, NULL if the setting does not exist.
     */
    function theme_get_setting($setting_name, $refresh = FALSE) {
      global $theme_key;
      static $settings;
    
      if (empty($settings) || $refresh) {
        $settings = theme_get_settings($theme_key);
    
        $themes = list_themes();
        $theme_object = $themes[$theme_key];
    
        if ($settings['toggle_logo']) {
          if ($settings['default_logo']) {
            $settings['logo'] = file_create_url(dirname($theme_object->filename) . '/logo.png');
          }
          elseif ($settings['logo_path']) {
            $settings['logo'] = file_create_url($settings['logo_path']);
          }
        }
    
        if ($settings['toggle_favicon']) {
          if ($settings['default_favicon']) {
            if (file_exists($favicon = dirname($theme_object->filename) . '/favicon.ico')) {
              $settings['favicon'] = file_create_url($favicon);
            }
            else {
              $settings['favicon'] = file_create_url('misc/favicon.ico');
            }
          }
          elseif ($settings['favicon_path']) {
            $settings['favicon'] = file_create_url($settings['favicon_path']);
          }
          else {
            $settings['toggle_favicon'] = FALSE;
          }
        }
      }
    
      return isset($settings[$setting_name]) ? $settings[$setting_name] : NULL;
    }
    
    /**
     * Render a system default template, which is essentially a PHP template.
     *
     * @param $template_file
     *   The filename of the template to render. Note that this will overwrite
     *   anything stored in $variables['template_file'] if using a variable processor hook.
     * @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
      $contents = ob_get_contents();                // Get the contents of the buffer
      ob_end_clean();                               // End buffering and discard
      return $contents;                             // Return the contents
    }
    
    /**
     * @defgroup themeable Default theme implementations
     * @{
     * Functions and templates that present output to the user, and can be
     * implemented by themes.
     *
     * Drupal's presentation layer is a pluggable system known as the theme
     * layer. Each theme can take control over most of Drupal's output, and
     * has complete control over the CSS.
     *
     * Inside Drupal, the theme layer is utilized by the use of the theme()
     * function, which is passed the name of a component (the theme hook)
     * and several arguments. For example, theme('table', $header, $rows);
     * Additionally, the theme() function can take an array of theme
     * hooks, which can be used to provide 'fallback' implementations to
     * allow for more specific control of output. For example, the function:
     * theme(array('table__foo', 'table'), $header, $rows) would look to see if
     * 'table__foo' is registered anywhere; if it is not, it would 'fall back'
     * to the generic 'table' implementation. This can be used to attach specific
     * theme functions to named objects, allowing the themer more control over
     * specific types of output.
     *
     * As of Drupal 6, every theme hook is required to be registered by the
     * module that owns it, so that Drupal can tell what to do with it and
     * to make it simple for themes to identify and override the behavior
     * for these calls.
     *
     * The theme hooks are registered via hook_theme(), which returns an
     * array of arrays with information about the hook. It describes the
     * arguments the function or template will need, and provides
     * defaults for the template in case they are not filled in. If the default
     * implementation is a function, by convention it is named theme_HOOK().
     *
     * Each module should provide a default implementation for theme_hooks that
     * it registers. This implementation may be either a function or a template;
     * if it is a function it must be specified via hook_theme(). By convention,
     * default implementations of theme hooks are named theme_HOOK. Default
     * template implementations are stored in the module directory.
     *
     * Drupal's default template renderer is a simple PHP parsing engine that
     * includes the template and stores the output. Drupal's theme engines
     * can provide alternate template engines, such as XTemplate, Smarty and
     * PHPTal. The most common template engine is PHPTemplate (included with
     * Drupal and implemented in phptemplate.engine, which uses Drupal's default
     * template renderer.
     *
     * In order to create theme-specific implementations of these hooks, themes can
     * implement their own version of theme hooks, either as functions or templates.
     * These implementations will be used instead of the default implementation. If
     * using a pure .theme without an engine, the .theme is required to implement
     * its own version of hook_theme() to tell Drupal what it is implementing;
     * themes utilizing an engine will have their well-named theming functions
     * automatically registered for them. While this can vary based upon the theme
     * engine, the standard set by phptemplate is that theme functions should be
     * named THEMENAME_HOOK. For example, for Drupal's default theme (Garland) to
     * implement the 'table' hook, the phptemplate.engine would find
     * garland_table().
     *
     * The theme system is described and defined in theme.inc.
     *
     * @see theme()
     * @see hook_theme()
     */
    
    /**
     * Formats text for emphasized display in a placeholder inside a sentence.
     * Used automatically by t().
     *
     * @param $text
     *   The text to format (plain-text).
     * @return
     *   The formatted text (html).
     */
    function theme_placeholder($text) {
      return '<em>' . check_plain($text) . '</em>';
    }
    
    /**
     * Return a themed set of status and/or error messages. The messages are 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 $display
     *   (optional) Set to 'status' or 'error' to display only messages of that type.
     *
     * @return
     *   A string containing the messages.
     */
    function theme_status_messages($display = NULL) {
      $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;
    }
    
    /**
     * Return a themed set of links.
     *
     * @param $links
     *   A keyed 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 keys:
     *    - 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) set this to TRUE if 'title' is HTML so it will be escaped.
     *   Array items are passed on to the l() function's $options parameter when creating the link.
     * @param $attributes
     *   A keyed array of attributes.
     * @param $heading
     *   An optional keyed array or a string for a heading to precede the links.
     *   When using an array the following keys can be used:
     *    - text: the heading text
     *    - level: the heading level (e.g. 'h2', 'h3')
     *    - class: (optional) an array of the CSS classes for the heading
     *   When using a string it will be used as the text of the heading and the
     *   level will default to 'h2'.
     *   Headings should be used on navigation menus and any list of links that
     *   consistently appears on multiple pages. To make the heading invisible
     *   use the 'element-invisible' CSS class. Do not use 'display:none', which
     *   removes it from screen-readers and assistive technology. Headings allow
     *   screen-reader and keyboard only users to navigate to or skip the links.
     *   See http://juicystudio.com/article/screen-readers-display-none.php
     *   and http://www.w3.org/TR/WCAG-TECHS/H42.html for more information.
     * @return
     *   A string containing an unordered list of links.
     */
    function theme_links($links, $attributes = array('class' => array('links')), $heading = array()) {
      global $language;
      $output = '';
    
      if (count($links) > 0) {
        $output = '';
    
        // Treat the heading first if it is present to prepend it to the
        // list of links.
        if (!empty($heading)) {
          if (is_string($heading)) {
            // Prepare the array that will be used when the passed heading
            // is a string.
            $heading = array(
              'text' => $heading,
              // Set the default level of the heading.
              'level' => 'h2',
            );
          }
          $output .= '<' . $heading['level'];
          if (!empty($heading['class'])) {
            $output .= drupal_attributes(array('class' => $heading['class']));
          }
          $output .= '>' . check_plain($heading['text']) . '</' . $heading['level'] . '>';
        }
    
        $output .= '<ul' . drupal_attributes($attributes) . '>';
    
        $num_links = count($links);
        $i = 1;
    
        foreach ($links as $key => $link) {
          $class = array($key);
    
          // Add first, last and active classes to the list of links to help out themers.
          if ($i == 1) {
            $class[] = 'first';
          }
          if ($i == $num_links) {
            $class[] = 'last';
          }
          if (isset($link['href']) && ($link['href'] == $_GET['q'] || ($link['href'] == '<front>' && drupal_is_front_page()))
              && (empty($link['language']) || $link['language']->language == $language->language)) {
            $class[] = 'active';
          }
          $output .= '<li' . drupal_attributes(array('class' => $class)) . '>';
    
          if (isset($link['href'])) {
            // Pass in $link as $options, they share the same keys.
            $output .= l($link['title'], $link['href'], $link);
          }
          elseif (!empty($link['title'])) {
            // Some links are actually not links, but we wrap these in <span> for adding title and class attributes.
            if (empty($link['html'])) {
              $link['title'] = check_plain($link['title']);
            }
            $span_attributes = '';
            if (isset($link['attributes'])) {
              $span_attributes = drupal_attributes($link['attributes']);
            }
            $output .= '<span' . $span_attributes . '>' . $link['title'] . '</span>';
          }
    
          $i++;
          $output .= "</li>\n";
        }
    
        $output .= '</ul>';
      }
    
      return $output;
    }
    
    /**
     * Return a themed image.
     *
     * @param $path
     *   Either the path of the image file (relative to base_path()) or a full URL.
     * @param $alt
     *   The alternative text for text-based browsers.
     * @param $title
     *   The title text is displayed when the image is hovered in some popular browsers.
     * @param $attributes
     *   Associative array of attributes to be placed in the img tag.
     * @param $getsize
     *   If set to TRUE, the image's dimension are fetched and added as width/height attributes.
     * @return
     *   A string containing the image tag.
     */
    function theme_image($path, $alt = '', $title = '', $attributes = array(), $getsize = TRUE) {
      if (!$getsize || (is_file($path) && (list($width, $height, $type, $image_attributes) = @getimagesize($path)))) {
        $attributes = drupal_attributes($attributes);
        $url = file_create_url($path);
        return '<img src="' . check_url($url) . '" alt="' . check_plain($alt) . '" title="' . check_plain($title) . '" ' . (isset($image_attributes) ? $image_attributes : '') . $attributes . ' />';
      }
    }
    
    /**
     * Return a themed breadcrumb trail.
     *
     * @param $breadcrumb
     *   An array containing the breadcrumb links.
     * @return a string containing the breadcrumb output.
     */
    function theme_breadcrumb($breadcrumb) {
      if (!empty($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 .= '<div class="breadcrumb">' . implode(' » ', $breadcrumb) . '</div>';
        return $output;
      }
    }
    
    /**
     * Return a themed submenu, typically displayed under the tabs.
     *
     * @param $links
     *   An array of links.
     */
    function theme_submenu($links) {
      return '<div class="submenu">' . implode(' | ', $links) . '</div>';
    }
    
    /**
     * Return a themed table.
     *
     * @param $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").
     *   - Any HTML attributes, such as "colspan", to apply to the column header cell.
     * @param $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.
     *
     *   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:
     *   @verbatim
     *   $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')
     *     )
     *   );
     *   @endverbatim
     *
     * @param $attributes
     *   An array of HTML attributes to apply to the table tag.
     * @param $caption
     *   A localized string to use for the <caption> tag.
     * @param $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:
     *   @verbatim
     *   $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.
     *     ),
     *   );
     *   @endverbatim
     *   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.
     * @param $sticky
     *   Use a "sticky" table header.
     * @return
     *   An HTML string representing the table.
     */
    function theme_table($header, $rows, $attributes = array(), $caption = NULL, $colgroups = array(), $sticky = TRUE) {
    
      // Add sticky headers, if applicable.
      if (count($header) && $sticky) {
        drupal_add_js('misc/tableheader.js');
        // 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';
      }
    
      $output = '<table' . drupal_attributes($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)) {
            $output .= ' <colgroup' . drupal_attributes($attributes) . '>';
            $i = 0;
            foreach ($cols as $col) {
              $output .= ' <col' . drupal_attributes($col) . ' />';
            }
            $output .= " </colgroup>\n";
          }
          else {
            $output .= ' <colgroup' . drupal_attributes($attributes) . " />\n";
          }
        }
      }
    
      // 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>');
        foreach ($header as $cell) {
          $cell = tablesort_header($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
            $class = $flip[$class];
            $attributes['class'][] = $class;
    
            // Build row
            $output .= ' <tr' . drupal_attributes($attributes) . '>';
            $i = 0;
            foreach ($cells as $cell) {
              $cell = tablesort_cell($cell, $header, $ts, $i++);
              $output .= _theme_table_cell($cell);
            }
            $output .= " </tr>\n";
          }
        }
        $output .= "</tbody>\n";
      }
    
      $output .= "</table>\n";
      return $output;
    }
    
    /**
     * Returns a header cell for tables that have a select all functionality.
     */
    function theme_table_select_header_cell() {
      drupal_add_js('misc/tableselect.js');
    
      return array('class' => array('select-all'));
    }
    
    /**
     * Return a themed sort icon.
     *
     * @param $style
     *   Set to either asc or desc. This sets which icon to show.
     * @return
     *   A themed sort icon.
     */
    function theme_tablesort_indicator($style) {
      if ($style == "asc") {
        return theme('image', 'misc/arrow-asc.png', t('sort icon'), t('sort ascending'));
      }
      else {
        return theme('image', 'misc/arrow-desc.png', t('sort icon'), t('sort descending'));
      }
    }
    
    /**
     * Return a themed marker, useful for marking new or updated
     * content.
     *
     * @param $type
     *   Number representing the marker type to display
     * @see MARK_NEW, MARK_UPDATED, MARK_READ
     * @return
     *   A string containing the marker.
     */
    function theme_mark($type = MARK_NEW) {
      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>';
        }
      }
    }
    
    /**
     * Return a themed list of items.
     *
     * @param $items
     *   An array of items to be displayed in the list. If an item is a string,
     *   then it is used as is. If an item is an array, then the "data" element of
     *   the array is used as the contents of the list item. If an item is an array
     *   with a "children" element, those children are displayed in a nested list.
     *   All other elements are treated as attributes of the list item element.
     * @param $title
     *   The title of the list.
     * @param $type
     *   The type of list to return (e.g. "ul", "ol")
     * @param $attributes
     *   The attributes applied to the list element.
     * @return
     *   A string containing the list output.
     */
    function theme_item_list($items = array(), $title = NULL, $type = 'ul', $attributes = array()) {
      $output = '<div class="item-list">';
      if (isset($title)) {
        $output .= '<h3>' . $title . '</h3>';
      }
    
      if (!empty($items)) {
        $output .= "<$type" . drupal_attributes($attributes) . '>';
        $num_items = count($items);
        foreach ($items as $i => $item) {
          $attributes = array();
          $children = array();
          if (is_array($item)) {
            foreach ($item as $key => $value) {
              if ($key == 'data') {
                $data = $value;
              }
              elseif ($key == 'children') {
                $children = $value;
              }
              else {
                $attributes[$key] = $value;
              }
            }
          }
          else {
            $data = $item;
          }
          if (count($children) > 0) {
            $data .= theme_item_list($children, NULL, $type, $attributes); // Render nested list
          }
          if ($i == 0) {
            $attributes['class'][] = 'first';
          }
          if ($i == $num_items - 1) {
            $attributes['class'][] = 'last';
          }
          $output .= '<li' . drupal_attributes($attributes) . '>' . $data . "</li>\n";
        }
        $output .= "</$type>";
      }
      $output .= '</div>';
      return $output;
    }
    
    /**
     * Returns code that emits the 'more help'-link.
     */
    function theme_more_help_link($url) {
      return '<div class="more-help-link">' . t('<a href="@link">More help</a>', array('@link' => check_url($url))) . '</div>';
    }
    
    /**
     * Return code that emits an feed icon.
     *
     * @param $url
     *   The url of the feed.
     * @param $title
     *   A descriptive title of the feed.
     */
    function theme_feed_icon($url, $title) {
      $text = t('Subscribe to @feed-title', array('@feed-title' => $title));
      if ($image = theme('image', 'misc/feed.png', $text)) {
        return '<a href="' . check_url($url) . '" title="' . $text . '" class="feed-icon">' . $image . '</a>';
      }
    }
    
    /**
     * Returns code that emits the 'more' link used on blocks.
     *
     * @param $url
     *   The url of the main page
     * @param $title
     *   A descriptive verb for the link, like 'Read more'
     */
    function theme_more_link($url, $title) {
      return '<div class="more-link">' . t('<a href="@link" title="@title">more</a>', array('@link' => check_url($url), '@title' => $title)) . '</div>';
    }
    
    /**
     * Preprocess variables for theme_username().
     *
     * Modules that make any changes to the $variables['object'] properties like
     * 'name' or 'extra' must insure that the final string is safe to include
     * directly in the ouput by using check_plain() or filter_xss().
     *
     * @see theme_username().
     */
    function template_preprocess_username(&$variables) {
      $account = $variables['object'];
      // Create a new empty object to populate with standardized data.
      $variables['object'] = new stdClass;
      // Keep a reference to the original data.
      $variables['object']->account = $account;
      $variables['object']->extra = '';
      if (empty($account->uid)) {
        $variables['object']->uid = 0;
        if (theme_get_setting('toggle_comment_user_verification')) {
          $variables['object']->extra = ' (' . t('not verified') . ')';
        }
      }
      else {
        $variables['object']->uid = (int)$account->uid;
      }
      if (empty($account->name)) {
        $variables['object']->name = variable_get('anonymous', t('Anonymous'));
      }
      else {
        $variables['object']->name = $account->name;
      }
    
      $variables['object']->profile_access = user_access('access user profiles');
      $variables['object']->link_attributes = array();
      // Populate link path and attributes if appropriate.
      if ($variables['object']->uid && $variables['object']->profile_access) {
        // We are linking to a local user.
        $variables['object']->link_attributes = array('title' => t('View user profile.'));
        $variables['object']->link_path = 'user/' . $variables['object']->uid;
      }
      elseif (!empty($account->homepage)) {
        $variables['object']->link_attributes = array('rel' => 'nofollow');
        $variables['object']->link_path = $account->homepage;
        $variables['object']->homepage = $account->homepage;
      }
      // We do not want the l() function to check_plain() a second time.
      $variables['object']->link_options['html'] = TRUE;
      // Set a default class.
      $variables['object']->attributes = array('class' => array('username'));
      // Shorten the name when it is too long or it will break many tables.
      if (drupal_strlen($variables['object']->name) > 20) {
        $variables['object']->name = drupal_substr($variables['object']->name, 0, 15) . '...';
      }
      // Make sure name is safe for use in the theme function.
      $variables['object']->name = check_plain($variables['object']->name);
    }
    
    /**
     * Process variables for theme_username().
     *
     * @see theme_username().
     */
    function template_process_username(&$variables) {
      // Finalize the link_options array for passing to the l() function.
      // This is done in the process phase so that attributes may be added by
      // modules or the theme during the preprocess phase.
      if (isset($variables['object']->link_path)) {
        $variables['object']->link_options['attributes'] = $variables['object']->link_attributes + $variables['object']->attributes;
      }
    }
    
    /**
     * Format a username.
     *
     * @param $object
     *   The user object to format, which has been processed to provide safe and
     *   standarized elements. The object keys 'name', and 'extra' are safe strings
     *   that can be used directly.
     *
     * @return
     *   A string containing an HTML link to the user's page if the passed object
     *   suggests that this is a site user. Otherwise, only the username is returned.
     *
     * @see template_preprocess_username()
     * @see template_process_username()
     */
    function theme_username($object) {
      if (isset($object->link_path)) {
        // We have a link path, so we should generate a link using l().
        // Additional classes may be added as array elements like
        // $object->link_options['attributes']['class'][] = 'myclass';
        $output = l($object->name . $object->extra, $object->link_path, $object->link_options);
      }
      else {
        // Modules may have added important attributes so they must be included
        // in the output. Additional classes may be added as array elements like
        // $object->attributes['class'][] = 'myclass';
        $output = '<span' . drupal_attributes($object->attributes) . '>' . $object->name . $object->extra . '</span>';
      }
      return $output;
    }
    
    /**
     * Return a themed progress bar.
     *
     * @param $percent
     *   The percentage of the progress.
     * @param $message
     *   A string containing information to be displayed.
     * @return
     *   A themed HTML string representing the progress bar.
     */
    function theme_progress_bar($percent, $message) {
      $output = '<div id="progress" class="progress">';
      $output .= '<div class="bar"><div class="filled" style="width: ' . $percent . '%"></div></div>';
      $output .= '<div class="percentage">' . $percent . '%</div>';
      $output .= '<div class="message">' . $message . '</div>';
      $output .= '</div>';
    
      return $output;
    }
    
    /**
     * Create a standard indentation div. Used for drag and drop tables.
     *
     * @param $size
     *   Optional. The number of indentations to create.
     * @return
     *   A string containing indentations.
     */
    function theme_indentation($size = 1) {
      $output = '';
      for ($n = 0; $n < $size; $n++) {
        $output .= '<div class="indentation">&nbsp;</div>';
      }
      return $output;
    }
    
    /**
     * @} End of "defgroup themeable".
     */
    
    function _theme_table_cell($cell, $header = FALSE) {
      $attributes = '';
    
      if (is_array($cell)) {
        $data = isset($cell['data']) ? $cell['data'] : '';
        $header |= isset($cell['header']);
        unset($cell['data']);
        unset($cell['header']);
        $attributes = drupal_attributes($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 comes in before any other preprocess function which makes it possible to
     * be used in default theme implementations (non-overriden theme functions).
     */
    function template_preprocess(&$variables, $hook) {
      global $user;
      static $count = array();
    
      // 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();
    
      // Initialize html class attribute for the current hook.
      $variables['classes_array'] = array($hook);
    
      // Initialize attributes for the top-level template entity and its title.
      $variables['attributes_array'] = array();
      $variables['title_attributes_array'] = array();
    
      // Set default variables that depend on the database.
      $variables['is_admin']            = FALSE;
      $variables['is_front']            = FALSE;
      $variables['logged_in']           = FALSE;
      if ($variables['db_is_active'] = db_is_active()  && !defined('MAINTENANCE_MODE')) {
        // Check for administrators.
        if (user_access('access administration pages')) {
          $variables['is_admin'] = TRUE;
        }
        // Flag front page status.
        $variables['is_front'] = drupal_is_front_page();
        // Tell all templates by which kind of user they're viewed.
        $variables['logged_in'] = ($user->uid > 0);
        // Provide user object to all templates
        $variables['user'] = $user;
      }
    }
    
    /**
     * A default process function used to alter variables as late as possible.
     */
    function template_process(&$variables, $hook) {
      // Flatten out classes.
      $variables['classes'] = implode(' ', $variables['classes_array']);
    
      // Flatten out attributes and title_attributes.
      $variables['attributes'] = drupal_attributes($variables['attributes_array']);
      $variables['title_attributes'] = drupal_attributes($variables['title_attributes_array']);
    }
    
    /**
     * Preprocess variables for html.tpl.php
     *
     * @see system_elements()
     * @see html.tpl.php
     */
    function template_preprocess_html(&$variables) {
      // 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['classes_array'][] = $variables['is_front'] ? 'front' : 'not-front';
      // Add a class that tells us whether the page is viewed by an authenticated user or not.
      $variables['classes_array'][] = $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'])) {
        $variables['classes_array'][] = 'two-sidebars';
      }
      elseif (!empty($variables['page']['sidebar_first'])) {
        $variables['classes_array'][] = 'one-sidebar sidebar-first';
      }
      elseif (!empty($variables['page']['sidebar_second'])) {
        $variables['classes_array'][] = 'one-sidebar sidebar-second';
      }
      else {
        $variables['classes_array'][] = 'no-sidebars';
      }
      
      // Populate the body classes.
      if ($suggestions = template_page_suggestions(arg(), 'page')) {
        foreach ($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.
            $variables['classes_array'][] = drupal_html_class($suggestion);
          }
        }
      }
      
      // If on an individual node page, add the node type to body classes.
      if ($node = menu_get_object()) {
        $variables['classes_array'][] = drupal_html_class('node-type-' . $node->type);
      }
    
      // RDFa allows annotation of XHTML pages with RDF data, while GRDDL provides
      // mechanisms for extraction of this RDF content via XSLT transformation
      // using an associated GRDDL profile.
      $variables['rdf_namespaces']    = drupal_get_rdf_namespaces();
      $variables['grddl_profile']     = 'http://ns.inria.fr/grddl/rdfa/';
      $variables['language']          = $GLOBALS['language'];
      $variables['language']->dir     = $GLOBALS['language']->direction ? 'rtl' : 'ltr';
    
      // Add favicon.
      if (theme_get_setting('toggle_favicon')) {
        $favicon = theme_get_setting('favicon');
        $type = theme_get_setting('favicon_mimetype');
        drupal_add_html_head('<link rel="shortcut icon" href="' . check_url($favicon) . '" type="' . check_plain($type) . '" />');
      }
    
      // Construct page title.
      if (drupal_get_title()) {
        $head_title = array(strip_tags(drupal_get_title()), variable_get('site_name', 'Drupal'));
      }
      else {
        $head_title = array(variable_get('site_name', 'Drupal'));
        if (variable_get('site_slogan', '')) {
          $head_title[] = variable_get('site_slogan', '');
        }
      }
      $variables['head_title'] = implode(' | ', $head_title);
      
      // Populate the page template suggestions.
      if ($suggestions = template_page_suggestions(arg(), 'html')) {
        $variables['template_files'] = $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) {
      // Move some variables to the top level for themer convenience and template cleanliness.
      $variables['show_messages'] = $variables['page']['#show_messages'];
    
      // Set up layout variable.
      $variables['layout'] = 'none';
      if (!empty($variables['page']['sidebar_first'])) {
        $variables['layout'] = 'first';
      }
      else {
        $variables['page']['sidebar_first'] = array();
      }
      if (!empty($variables['page']['sidebar_second'])) {
        $variables['layout'] = ($variables['layout'] == 'first') ? 'both' : 'second';
      }
      else {
        $variables['page']['sidebar_second'] = array();
      }
    
      $variables['base_path']         = base_path();
      $variables['front_page']        = url();
      $variables['breadcrumb']        = theme('breadcrumb', drupal_get_breadcrumb());
      $variables['feed_icons']        = drupal_get_feeds();
      $variables['language']          = $GLOBALS['language'];
      $variables['language']->dir     = $GLOBALS['language']->direction ? 'rtl' : 'ltr';
      $variables['logo']              = theme_get_setting('logo');
      $variables['messages']          = $variables['show_messages'] ? theme('status_messages') : '';
      $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') ? filter_xss_admin(variable_get('site_name', 'Drupal')) : '');
      $variables['site_slogan']       = (theme_get_setting('toggle_slogan') ? filter_xss_admin(variable_get('site_slogan', '')) : '');
      $variables['tabs']              = theme('menu_local_tasks');
      $variables['title']             = drupal_get_title();
    
      if ($node = menu_get_object()) {
        $variables['node'] = $node;
      }
    
      // Populate the page template suggestions.
      if ($suggestions = template_page_suggestions(arg(), 'page')) {
        $variables['template_files'] = $suggestions;
      }
    }
    /**
     * 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) {
      // 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 page template suggestions.
     *
     * @param $args
     *   An array of path arguments, such as from function arg().
     *
     * @return
     *   An array of suggested template files.
     */
    function template_page_suggestions($args, $suggestion) {
    
      // Build a list of suggested template files and 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, http://www.example.com/node/1/edit would result in the following
      // suggestions and body classes:
      //
      // page-node-edit.tpl.php  page-node-edit
      // page-node-1.tpl.php     page-node-1
      // page-node.tpl.php       page-node
      // page.tpl.php
    
      $suggestions = array();
      foreach ($args as $arg) {
        // Remove slashes or null per SA-CORE-2009-003.
        $arg = str_replace(array("/", "\\", "\0"), '', $arg);
        // The percent acts as a wildcard for numeric arguments since
        // asterisks are not valid filename characters on many filesystems.
        if (is_numeric($arg)) {
          $suggestions[] = $suggestion . '-%';
        }
        $suggestions[] = $suggestion . '-' . $arg;
        if (!is_numeric($arg)) {
          $suggestion .= '-' . $arg;
        }
      }
      if (drupal_is_front_page()) {
        $suggestions[] = $suggestion . '-front';
      }
    
      return $suggestions;
    }
    
    /**
     * The variables generated here is a mirror of template_preprocess_page().
     * This preprocessor will run it's course when theme_maintenance_page() is
     * invoked. It is also used in theme_install_page() and theme_update_page() to
     * keep all the variables consistent.
     *
     * 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) {
      // Add favicon
      if (theme_get_setting('toggle_favicon')) {
        $favicon = theme_get_setting('favicon');
        $type = theme_get_setting('favicon_mimetype');
        drupal_add_html_head('<link rel="shortcut icon" href="' . check_url($favicon) . '" type="' . check_plain($type) . '" />');
      }
    
      global $theme;
      // Retrieve the theme data to list all available regions.
      $theme_data = _system_get_theme_data();
      $regions = $theme_data[$theme]->info['regions'];
    
      // 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';
      }
    
      // Construct page title
      if (drupal_get_title()) {
        $head_title = array(strip_tags(drupal_get_title()), variable_get('site_name', 'Drupal'));
      }
      else {
        $head_title = array(variable_get('site_name', 'Drupal'));
        if (variable_get('site_slogan', '')) {
          $head_title[] = variable_get('site_slogan', '');
        }
      }
      $variables['head_title']        = implode(' | ', $head_title);
      $variables['base_path']         = base_path();
      $variables['front_page']        = url();
      $variables['breadcrumb']        = '';
      $variables['feed_icons']        = '';
      $variables['head']              = drupal_get_html_head();
      $variables['help']              = '';
      $variables['language']          = $GLOBALS['language'];
      $variables['language']->dir     = $GLOBALS['language']->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') ? variable_get('site_name', 'Drupal') : '');
      $variables['site_slogan']       = (theme_get_setting('toggle_slogan') ? variable_get('site_slogan', '') : '');
      $variables['css']               = drupal_add_css();
      $variables['styles']            = drupal_get_css();
      $variables['scripts']           = drupal_get_js();
      $variables['tabs']              = '';
      $variables['title']             = drupal_get_title();
      $variables['closure']           = '';
    
      // Compile a list of classes that are going to be applied to the body element.
      $variables['classes_array'][] = 'in-maintenance';
      if (isset($variables['db_is_active']) && !$variables['db_is_active']) {
        $variables['classes_array'][] = 'db-offline';
      }
      if ($variables['layout'] == 'both') {
        $variables['classes_array'][] = 'two-sidebars';
      }
      elseif ($variables['layout'] == 'none') {
        $variables['classes_array'][] = 'no-sidebars';
      }
      else {
        $variables['classes_array'][] = 'one-sidebar 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['template_file'] = 'maintenance-page-offline';
      }
    }