Skip to content
Snippets Groups Projects
Select Git revision
  • 7.x-1.7
  • 5.x default
  • str
  • bump-ddev-contrib2
  • no-libraries
  • Navigation-Extra-Tools
  • devel-5.x
  • phpcs
  • remove-kint
  • fix-tests
  • 4.x
  • refs
  • fix-webprofiler-test
  • 395-terms-with-deleted-parent-ids
  • 394-when-generating-terms-pass-the-devel_generate-settings-to-3rd-party-hooks
  • remove-min-stablility
  • use-1.6.0
  • 8.x-3.x
  • 8.x-2.x
  • refactor-gitlab-ci.yml
  • composer-runserver
  • 5.4.0
  • 5.3.1
  • 5.3.0
  • 5.2.1
  • 5.2.0
  • 5.1.2
  • 5.1.1
  • 5.1.0
  • 4.2.1
  • 5.0.2
  • 5.0.1
  • 5.0.0
  • 4.2.0
  • 4.2.0-beta1
  • 5.0.0-beta1
  • 4.1.5
  • 4.1.4
  • 4.1.3
  • 4.1.2
  • 4.1.1
41 results

devel_generate.inc

Blame
  • Code owners
    Assign users and groups as approvers for specific file changes. Learn more.
    form.inc 87.56 KiB
    <?php
    // $Id$
    
    /**
     * @defgroup form Form generation
     * @{
     * Functions to enable the processing and display of HTML forms.
     *
     * Drupal uses these functions to achieve consistency in its form processing and
     * presentation, while simplifying code and reducing the amount of HTML that
     * must be explicitly generated by modules.
     *
     * The drupal_get_form() function handles retrieving, processing, and
     * displaying a rendered HTML form for modules automatically. For example:
     *
     * @code
     * // Display the user registration form.
     * $output = drupal_get_form('user_register');
     * @endcode
     *
     * Forms can also be built and submitted programmatically without any user input
     * using the drupal_execute() function.
     *
     * For information on the format of the structured arrays used to define forms,
     * and more detailed explanations of the Form API workflow, see the
     * @link http://api.drupal.org/api/file/developer/topics/forms_api_reference.html reference @endlink
     * and the @link http://api.drupal.org/api/file/developer/topics/forms_api.html quickstart guide. @endlink
     */
    
    /**
     * Retrieves a form from a constructor function, or from the cache if
     * the form was built in a previous page-load. The form is then passesed
     * on for processing, after and rendered for display if necessary.
     *
     * @param $form_id
     *   The unique string identifying the desired form. If a function
     *   with that name exists, it is called to build the form array.
     *   Modules that need to generate the same form (or very similar forms)
     *   using different $form_ids can implement hook_forms(), which maps
     *   different $form_id values to the proper form constructor function. Examples
     *   may be found in node_forms(), search_forms(), and user_forms().
     * @param ...
     *   Any additional arguments are passed on to the functions called by
     *   drupal_get_form(), including the unique form constructor function.
     *   For example, the node_edit form requires that a node object be passed
     *   in here when it is called.
     * @return
     *   The rendered form.
     */
    function drupal_get_form($form_id) {
      $form_state = array('storage' => NULL, 'submitted' => FALSE);
    
      $args = func_get_args();
      $cacheable = FALSE;
    
      if (isset($_SESSION['batch_form_state'])) {
        // We've been redirected here after a batch processing : the form has
        // already been processed, so we grab the post-process $form_state value
        // and move on to form display. See _batch_finished() function.
        $form_state = $_SESSION['batch_form_state'];
        unset($_SESSION['batch_form_state']);
      }
      else {
        // If the incoming $_POST contains a form_build_id, we'll check the
        // cache for a copy of the form in question. If it's there, we don't
        // have to rebuild the form to proceed. In addition, if there is stored
        // form_state data from a previous step, we'll retrieve it so it can
        // be passed on to the form processing code.
        if (isset($_POST['form_id']) && $_POST['form_id'] == $form_id && !empty($_POST['form_build_id'])) {
          $form = form_get_cache($_POST['form_build_id'], $form_state);
        }
    
        // If the previous bit of code didn't result in a populated $form
        // object, we're hitting the form for the first time and we need
        // to build it from scratch.
        if (!isset($form)) {
          $form_state['post'] = $_POST;
          // Use a copy of the function's arguments for manipulation
          $args_temp = $args;
          array_shift($args_temp);
          array_unshift($args_temp, $form_state);
          array_unshift($args_temp, $form_id);
    
          $form = call_user_func_array('drupal_retrieve_form', $args_temp);
          $form_build_id = 'form-'. md5(mt_rand());
          $form['#build_id'] = $form_build_id;
          drupal_prepare_form($form_id, $form, $form_state);
          // Store a copy of the unprocessed form for caching and indicate that it
          // is cacheable if #cache will be set.
          $original_form = $form;
          $cacheable = TRUE;
          unset($form_state['post']);
        }
        $form['#post'] = $_POST;
    
        // Now that we know we have a form, we'll process it (validating,
        // submitting, and handling the results returned by its submission
        // handlers. Submit handlers accumulate data in the form_state by
        // altering the $form_state variable, which is passed into them by
        // reference.
        drupal_process_form($form_id, $form, $form_state);
        if ($cacheable && !empty($form['#cache'])) {
          // Caching is done past drupal_process_form so #process callbacks can
          // set #cache. By not sending the form state, we avoid storing
          // $form_state['storage'].
          form_set_cache($form_build_id, $original_form, NULL);
        }
      }
    
      // Most simple, single-step forms will be finished by this point --
      // drupal_process_form() usually redirects to another page (or to
      // a 'fresh' copy of the form) once processing is complete. If one
      // of the form's handlers has set $form_state['redirect'] to FALSE,
      // the form will simply be re-rendered with the values still in its
      // fields.
      //
      // If $form_state['storage'] or $form_state['rebuild'] have been
      // set by any submit or validate handlers, however, we know that
      // we're in a complex multi-part process of some sort and the form's
      // workflow is NOT complete. We need to construct a fresh copy of
      // the form, passing in the latest $form_state in addition to any
      // other variables passed into drupal_get_form().
    
      if (!empty($form_state['rebuild']) || !empty($form_state['storage'])) {
        $form = drupal_rebuild_form($form_id, $form_state, $args);
      }
    
      // If we haven't redirected to a new location by now, we want to
      // render whatever form array is currently in hand.
      return drupal_render_form($form_id, $form);
    }
    
    /**
     * Retrieves a form, caches it and processes it with an empty $_POST.
     *
     * This function clears $_POST and passes the empty $_POST to the form_builder.
     * To preserve some parts from $_POST, pass them in $form_state.
     *
     * If your AHAH callback simulates the pressing of a button, then your AHAH
     * callback will need to do the same as what drupal_get_form would do when the
     * button is pressed: get the form from the cache, run drupal_process_form over
     * it and then if it needs rebuild, run drupal_rebuild_form over it. Then send
     * back a part of the returned form.
     * $form_state['clicked_button']['#array_parents'] will help you to find which
     * part.
     *
     * @param $form_id
     *   The unique string identifying the desired form. If a function
     *   with that name exists, it is called to build the form array.
     *   Modules that need to generate the same form (or very similar forms)
     *   using different $form_ids can implement hook_forms(), which maps
     *   different $form_id values to the proper form constructor function. Examples
     *   may be found in node_forms(), search_forms(), and user_forms().
     * @param $form_state
     *   A keyed array containing the current state of the form. Most
     *   important is the $form_state['storage'] collection.
     * @param $args
     *   Any additional arguments are passed on to the functions called by
     *   drupal_get_form(), plus the original form_state in the beginning. If you
     *   are getting a form from the cache, use $form['#parameters'] to shift off
     *   the $form_id from its beginning then the resulting array can be used as
     *   $arg here.
     * @param $form_build_id
     *   If the AHAH callback calling this function only alters part of the form,
     *   then pass in the existing form_build_id so we can re-cache with the same
     *   csid.
     * @return
     *   The newly built form.
     */
    function drupal_rebuild_form($form_id, &$form_state, $args, $form_build_id = NULL) {
      // Remove the first argument. This is $form_id.when called from
      // drupal_get_form and the original $form_state when called from some AHAH
      // callback. Neither is needed.
      array_shift($args);
      // Put in the current state.
      array_unshift($args, $form_state);
      // And the form_id.
      array_unshift($args, $form_id);
      $form = call_user_func_array('drupal_retrieve_form', $args);
    
      if (!isset($form_build_id)) {
        // We need a new build_id for the new version of the form.
        $form_build_id = 'form-'. md5(mt_rand());
      }
      $form['#build_id'] = $form_build_id;
      drupal_prepare_form($form_id, $form, $form_state);
    
      // Now, we cache the form structure so it can be retrieved later for
      // validation. If $form_state['storage'] is populated, we'll also cache
      // it so that it can be used to resume complex multi-step processes.
      form_set_cache($form_build_id, $form, $form_state);
    
      // Clear out all post data, as we don't want the previous step's
      // data to pollute this one and trigger validate/submit handling,
      // then process the form for rendering.
      $_POST = array();
      $form['#post'] = array();
      drupal_process_form($form_id, $form, $form_state);
      return $form;
    }
    
    /**
     * Fetch a form from cache.
     */
    function form_get_cache($form_build_id, &$form_state) {
      if ($cached = cache_get('form_'. $form_build_id, 'cache_form')) {
        $form = $cached->data;
        if ($cached = cache_get('storage_'. $form_build_id, 'cache_form')) {
          $form_state['storage'] = $cached->data;
        }
        return $form;
      }
    }
    
    /**
     * Store a form in the cache
     */
    function form_set_cache($form_build_id, $form, $form_state) {
      $expire = max(ini_get('session.cookie_lifetime'), 86400);
    
      cache_set('form_'. $form_build_id, $form, 'cache_form', $expire);
      if (!empty($form_state['storage'])) {
        cache_set('storage_'. $form_build_id, $form_state['storage'], 'cache_form', $expire);
      }
    }
    
    /**
     * Retrieves a form using a form_id, populates it with $form_state['values'],
     * processes it, and returns any validation errors encountered. This
     * function is the programmatic counterpart to drupal_get_form().
     *
     * @param $form_id
     *   The unique string identifying the desired form. If a function
     *   with that name exists, it is called to build the form array.
     *   Modules that need to generate the same form (or very similar forms)
     *   using different $form_ids can implement hook_forms(), which maps
     *   different $form_id values to the proper form constructor function. Examples
     *   may be found in node_forms(), search_forms(), and user_forms().
     * @param $form_state
     *   A keyed array containing the current state of the form. Most
     *   important is the $form_state['values'] collection, a tree of data
     *   used to simulate the incoming $_POST information from a user's
     *   form submission.
     * @param ...
     *   Any additional arguments are passed on to the functions called by
     *   drupal_execute(), including the unique form constructor function.
     *   For example, the node_edit form requires that a node object be passed
     *   in here when it is called.
     * For example:
     *
     * // register a new user
     * $form_state = array();
     * $form_state['values']['name'] = 'robo-user';
     * $form_state['values']['mail'] = 'robouser@example.com';
     * $form_state['values']['pass'] = 'password';
     * $form_state['values']['op'] = t('Create new account');
     * drupal_execute('user_register', $form_state);
     *
     * // Create a new node
     * $form_state = array();
     * $node = array('type' => 'story');
     * $form_state['values']['title'] = 'My node';
     * $form_state['values']['body'] = 'This is the body text!';
     * $form_state['values']['name'] = 'robo-user';
     * $form_state['values']['op'] = t('Save');
     * drupal_execute('story_node_form', $form_state, $node);
     */
    function drupal_execute($form_id, &$form_state) {
      $args = func_get_args();
      $form = call_user_func_array('drupal_retrieve_form', $args);
      $form['#post'] = $form_state['values'];
      drupal_prepare_form($form_id, $form, $form_state);
      drupal_process_form($form_id, $form, $form_state);
    }
    
    /**
     * Retrieves the structured array that defines a given form.
     *
     * @param $form_id
     *   The unique string identifying the desired form. If a function
     *   with that name exists, it is called to build the form array.
     *   Modules that need to generate the same form (or very similar forms)
     *   using different $form_ids can implement hook_forms(), which maps
     *   different $form_id values to the proper form constructor function.
     * @param $form_state
     *   A keyed array containing the current state of the form.
     * @param ...
     *   Any additional arguments needed by the unique form constructor
     *   function. Generally, these are any arguments passed into the
     *   drupal_get_form() or drupal_execute() functions after the first
     *   argument. If a module implements hook_forms(), it can examine
     *   these additional arguments and conditionally return different
     *   builder functions as well.
     */
    function drupal_retrieve_form($form_id, &$form_state) {
      static $forms;
    
      // We save two copies of the incoming arguments: one for modules to use
      // when mapping form ids to constructor functions, and another to pass to
      // the constructor function itself. We shift out the first argument -- the
      // $form_id itself -- from the list to pass into the constructor function,
      // since it's already known.
      $args = func_get_args();
      $saved_args = $args;
      array_shift($args);
      if (isset($form_state)) {
        array_shift($args);
      }
    
      // We first check to see if there's a function named after the $form_id.
      // If there is, we simply pass the arguments on to it to get the form.
      if (!function_exists($form_id)) {
        // In cases where many form_ids need to share a central constructor function,
        // such as the node editing form, modules can implement hook_forms(). It
        // maps one or more form_ids to the correct constructor functions.
        //
        // We cache the results of that hook to save time, but that only works
        // for modules that know all their form_ids in advance. (A module that
        // adds a small 'rate this comment' form to each comment in a list
        // would need a unique form_id for each one, for example.)
        //
        // So, we call the hook if $forms isn't yet populated, OR if it doesn't
        // yet have an entry for the requested form_id.
        if (!isset($forms) || !isset($forms[$form_id])) {
          $forms = module_invoke_all('forms', $form_id, $args);
        }
        $form_definition = $forms[$form_id];
        if (isset($form_definition['callback arguments'])) {
          $args = array_merge($form_definition['callback arguments'], $args);
        }
        if (isset($form_definition['callback'])) {
          $callback = $form_definition['callback'];
        }
      }
    
      array_unshift($args, $form_state);
    
      // If $callback was returned by a hook_forms() implementation, call it.
      // Otherwise, call the function named after the form id.
      $form = call_user_func_array(isset($callback) ? $callback : $form_id, $args);
    
      // We store the original function arguments, rather than the final $arg
      // value, so that form_alter functions can see what was originally
      // passed to drupal_retrieve_form(). This allows the contents of #parameters
      // to be saved and passed in at a later date to recreate the form.
      $form['#parameters'] = $saved_args;
      return $form;
    }
    
    /**
     * This function is the heart of form API. The form gets built, validated and in
     * appropriate cases, submitted.
     *
     * @param $form_id
     *   The unique string identifying the current form.
     * @param $form
     *   An associative array containing the structure of the form.
     * @param $form_state
     *   A keyed array containing the current state of the form. This
     *   includes the current persistent storage data for the form, and
     *   any data passed along by earlier steps when displaying a
     *   multi-step form. Additional information, like the sanitized $_POST
     *   data, is also accumulated here.
     */
    function drupal_process_form($form_id, &$form, &$form_state) {
      $form_state['values'] = array();
    
      $form = form_builder($form_id, $form, $form_state);
      // Only process the form if it is programmed or the form_id coming
      // from the POST data is set and matches the current form_id.
      if ((!empty($form['#programmed'])) || (!empty($form['#post']) && (isset($form['#post']['form_id']) && ($form['#post']['form_id'] == $form_id)))) {
        drupal_validate_form($form_id, $form, $form_state);
    
        // form_clean_id() maintains a cache of element IDs it has seen,
        // so it can prevent duplicates. We want to be sure we reset that
        // cache when a form is processed, so scenerios that result in
        // the form being built behind the scenes and again for the
        // browser don't increment all the element IDs needlessly.
        form_clean_id(NULL, TRUE);
    
        if ((!empty($form_state['submitted'])) && !form_get_errors() && empty($form_state['rebuild'])) {
          $form_state['redirect'] = NULL;
          form_execute_handlers('submit', $form, $form_state);
    
          // We'll clear out the cached copies of the form and its stored data
          // here, as we've finished with them. The in-memory copies are still
          // here, though.
          if (variable_get('cache', CACHE_DISABLED) == CACHE_DISABLED && !empty($form_state['values']['form_build_id'])) {
            cache_clear_all('form_'. $form_state['values']['form_build_id'], 'cache_form');
            cache_clear_all('storage_'. $form_state['values']['form_build_id'], 'cache_form');
          }
    
          // If batches were set in the submit handlers, we process them now,
          // possibly ending execution. We make sure we do not react to the batch
          // that is already being processed (if a batch operation performs a
          // drupal_execute).
          if ($batch =& batch_get() && !isset($batch['current_set'])) {
            // The batch uses its own copies of $form and $form_state for
            // late execution of submit handers and post-batch redirection.
            $batch['form'] = $form;
            $batch['form_state'] = $form_state;
            $batch['progressive'] = !$form['#programmed'];
            batch_process();
            // Execution continues only for programmatic forms.
            // For 'regular' forms, we get redirected to the batch processing
            // page. Form redirection will be handled in _batch_finished(),
            // after the batch is processed.
          }
    
          // If no submit handlers have populated the $form_state['storage']
          // bundle, and the $form_state['rebuild'] flag has not been set,
          // we're finished and should redirect to a new destination page
          // if one has been set (and a fresh, unpopulated copy of the form
          // if one hasn't). If the form was called by drupal_execute(),
          // however, we'll skip this and let the calling function examine
          // the resulting $form_state bundle itself.
          if (!$form['#programmed'] && empty($form_state['rebuild']) && empty($form_state['storage'])) {
             drupal_redirect_form($form, $form_state['redirect']);
          }
        }
      }
    }
    
    /**
     * Prepares a structured form array by adding required elements,
     * executing any hook_form_alter functions, and optionally inserting
     * a validation token to prevent tampering.
     *
     * @param $form_id
     *   A unique string identifying the form for validation, submission,
     *   theming, and hook_form_alter functions.
     * @param $form
     *   An associative array containing the structure of the form.
     * @param $form_state
     *   A keyed array containing the current state of the form. Passed
     *   in here so that hook_form_alter() calls can use it, as well.
     */
    function drupal_prepare_form($form_id, &$form, &$form_state) {
      global $user;
    
      $form['#type'] = 'form';
      $form['#programmed'] = isset($form['#post']);
    
      if (isset($form['#build_id'])) {
        $form['form_build_id'] = array(
          '#type' => 'hidden',
          '#value' => $form['#build_id'],
          '#id' => $form['#build_id'],
          '#name' => 'form_build_id',
        );
      }
    
      // Add a token, based on either #token or form_id, to any form displayed to
      // authenticated users. This ensures that any submitted form was actually
      // requested previously by the user and protects against cross site request
      // forgeries.
      if (isset($form['#token'])) {
        if ($form['#token'] === FALSE || $user->uid == 0 || $form['#programmed']) {
          unset($form['#token']);
        }
        else {
          $form['form_token'] = array('#type' => 'token', '#default_value' => drupal_get_token($form['#token']));
        }
      }
      else if (isset($user->uid) && $user->uid && !$form['#programmed']) {
        $form['#token'] = $form_id;
        $form['form_token'] = array(
          '#id' => form_clean_id('edit-'. $form_id .'-form-token'),
          '#type' => 'token',
          '#default_value' => drupal_get_token($form['#token']),
        );
      }
    
      if (isset($form_id)) {
        $form['form_id'] = array(
          '#type' => 'hidden',
          '#value' => $form_id,
          '#id' => form_clean_id("edit-$form_id"),
        );
      }
      if (!isset($form['#id'])) {
        $form['#id'] = form_clean_id($form_id);
      }
    
      $form += _element_info('form');
    
      if (!isset($form['#validate'])) {
        if (function_exists($form_id .'_validate')) {
          $form['#validate'] = array($form_id .'_validate');
        }
      }
    
      if (!isset($form['#submit'])) {
        if (function_exists($form_id .'_submit')) {
          // We set submit here so that it can be altered.
          $form['#submit'] = array($form_id .'_submit');
        }
      }
    
      drupal_alter('form_'. $form_id, $form, $form_state);
      drupal_alter('form', $form, $form_state, $form_id);
    }
    
    
    /**
     * Validates user-submitted form data from the $form_state using
     * the validate functions defined in a structured form array.
     *
     * @param $form_id
     *   A unique string identifying the form for validation, submission,
     *   theming, and hook_form_alter functions.
     * @param $form
     *   An associative array containing the structure of the form.
     * @param $form_state
     *   A keyed array containing the current state of the form. The current
     *   user-submitted data is stored in $form_state['values'], though
     *   form validation functions are passed an explicit copy of the
     *   values for the sake of simplicity. Validation handlers can also
     *   $form_state to pass information on to submit handlers. For example:
     *     $form_state['data_for_submision'] = $data;
     *   This technique is useful when validation requires file parsing,
     *   web service requests, or other expensive requests that should
     *   not be repeated in the submission step.
     */
    function drupal_validate_form($form_id, $form, &$form_state) {
      static $validated_forms = array();
    
      if (isset($validated_forms[$form_id])) {
        return;
      }
    
      // If the session token was set by drupal_prepare_form(), ensure that it
      // matches the current user's session.
      if (isset($form['#token'])) {
        if (!drupal_valid_token($form_state['values']['form_token'], $form['#token'])) {
          // Setting this error will cause the form to fail validation.
          form_set_error('form_token', t('Validation error, please try again. If this error persists, please contact the site administrator.'));
        }
      }
    
      _form_validate($form, $form_state, $form_id);
      $validated_forms[$form_id] = TRUE;
    }
    
    /**
     * Renders a structured form array into themed HTML.
     *
     * @param $form_id
     *   A unique string identifying the form for validation, submission,
     *   theming, and hook_form_alter functions.
     * @param $form
     *   An associative array containing the structure of the form.
     * @return
     *   A string containing the path of the page to display when processing
     *   is complete.
     */
    function drupal_render_form($form_id, &$form) {
      // Don't override #theme if someone already set it.
      if (!isset($form['#theme'])) {
        init_theme();
        $registry = theme_get_registry();
        if (isset($registry[$form_id])) {
          $form['#theme'] = $form_id;
        }
      }
    
      $output = drupal_render($form);
      return $output;
    }
    
    /**
     * Redirect the user to a URL after a form has been processed.
     *
     * @param $form
     *   An associative array containing the structure of the form.
     * @param $redirect
     *   An optional value containing the destination path to redirect
     *   to if none is specified by the form.
     */
    function drupal_redirect_form($form, $redirect = NULL) {
      $goto = NULL;
      if (isset($redirect)) {
        $goto = $redirect;
      }
      if ($goto !== FALSE && isset($form['#redirect'])) {
        $goto = $form['#redirect'];
      }
      if (!isset($goto) || ($goto !== FALSE)) {
        if (isset($goto)) {
          if (is_array($goto)) {
            call_user_func_array('drupal_goto', $goto);
          }
          else {
            drupal_goto($goto);
          }
        }
        drupal_goto($_GET['q']);
      }
    }
    
    /**
     * Performs validation on form elements. First ensures required fields are
     * completed, #maxlength is not exceeded, and selected options were in the
     * list of options given to the user. Then calls user-defined validators.
     *
     * @param $elements
     *   An associative array containing the structure of the form.
     * @param $form_state
     *   A keyed array containing the current state of the form. The current
     *   user-submitted data is stored in $form_state['values'], though
     *   form validation functions are passed an explicit copy of the
     *   values for the sake of simplicity. Validation handlers can also
     *   $form_state to pass information on to submit handlers. For example:
     *     $form_state['data_for_submision'] = $data;
     *   This technique is useful when validation requires file parsing,
     *   web service requests, or other expensive requests that should
     *   not be repeated in the submission step.
     * @param $form_id
     *   A unique string identifying the form for validation, submission,
     *   theming, and hook_form_alter functions.
     */
    function _form_validate($elements, &$form_state, $form_id = NULL) {
      // Also used in the installer, pre-database setup.
      $t = get_t();
    
      // Recurse through all children.
      foreach (element_children($elements) as $key) {
        if (isset($elements[$key]) && $elements[$key]) {
          _form_validate($elements[$key], $form_state);
        }
      }
      /* Validate the current input */
      if (!isset($elements['#validated']) || !$elements['#validated']) {
        if (isset($elements['#needs_validation'])) {
          // An empty textfield returns '' so we use empty(). An empty checkbox
          // and a textfield could return '0' and empty('0') returns TRUE so we
          // need a special check for the '0' string.
          if ($elements['#required'] && empty($elements['#value']) && $elements['#value'] !== '0') {
            form_error($elements, $t('!name field is required.', array('!name' => $elements['#title'])));
          }
    
          // Verify that the value is not longer than #maxlength.
          if (isset($elements['#maxlength']) && drupal_strlen($elements['#value']) > $elements['#maxlength']) {
            form_error($elements, $t('!name cannot be longer than %max characters but is currently %length characters long.', array('!name' => empty($elements['#title']) ? $elements['#parents'][0] : $elements['#title'], '%max' => $elements['#maxlength'], '%length' => drupal_strlen($elements['#value']))));
          }
    
          if (isset($elements['#options']) && isset($elements['#value'])) {
            if ($elements['#type'] == 'select') {
              $options = form_options_flatten($elements['#options']);
            }
            else {
              $options = $elements['#options'];
            }
            if (is_array($elements['#value'])) {
              $value = $elements['#type'] == 'checkboxes' ? array_keys(array_filter($elements['#value'])) : $elements['#value'];
              foreach ($value as $v) {
                if (!isset($options[$v])) {
                  form_error($elements, $t('An illegal choice has been detected. Please contact the site administrator.'));
                  watchdog('form', 'Illegal choice %choice in !name element.', array('%choice' => $v, '!name' => empty($elements['#title']) ? $elements['#parents'][0] : $elements['#title']), WATCHDOG_ERROR);
                }
              }
            }
            elseif (!isset($options[$elements['#value']])) {
              form_error($elements, $t('An illegal choice has been detected. Please contact the site administrator.'));
              watchdog('form', 'Illegal choice %choice in %name element.', array('%choice' => $elements['#value'], '%name' => empty($elements['#title']) ? $elements['#parents'][0] : $elements['#title']), WATCHDOG_ERROR);
            }
          }
        }
    
        // Call user-defined form level validators.
        if (isset($form_id)) {
          form_execute_handlers('validate', $elements, $form_state);
        }
        // Call any element-specific validators. These must act on the element
        // #value data.
        elseif (isset($elements['#element_validate'])) {
          foreach ($elements['#element_validate'] as $function) {
            if (function_exists($function))  {
              $function($elements, $form_state);
            }
          }
        }
        $elements['#validated'] = TRUE;
      }
    }
    
    /**
     * A helper function used to execute custom validation and submission
     * handlers for a given form. Button-specific handlers are checked
     * first. If none exist, the function falls back to form-level handlers.
     *
     * @param $type
     *   The type of handler to execute. 'validate' or 'submit' are the
     *   defaults used by Form API.
     * @param $form
     *   An associative array containing the structure of the form.
     * @param $form_state
     *   A keyed array containing the current state of the form. If the user
     *   submitted the form by clicking a button with custom handler functions
     *   defined, those handlers will be stored here.
     */
    function form_execute_handlers($type, &$form, &$form_state) {
      $return = FALSE;
      if (isset($form_state[$type .'_handlers'])) {
        $handlers = $form_state[$type .'_handlers'];
      }
      elseif (isset($form['#'. $type])) {
        $handlers = $form['#'. $type];
      }
      else {
        $handlers = array();
      }
    
      foreach ($handlers as $function) {
        if (function_exists($function))  {
          if ($type == 'submit' && ($batch =& batch_get())) {
            // Some previous _submit handler has set a batch. We store the call
            // in a special 'control' batch set, for execution at the correct
            // time during the batch processing workflow.
            $batch['sets'][] = array('form_submit' => $function);
          }
          else {
            $function($form, $form_state);
          }
          $return = TRUE;
        }
      }
      return $return;
    }
    
    /**
     * File an error against a form element. If the name of the element is
     * edit[foo][bar] then you may pass either foo or foo][bar as $name
     * foo will set an error for all its children.
     */
    function form_set_error($name = NULL, $message = '') {
      static $form = array();
      if (isset($name) && !isset($form[$name])) {
        $form[$name] = $message;
        if ($message) {
          drupal_set_message($message, 'error');
        }
      }
      return $form;
    }
    
    /**
     * Return an associative array of all errors.
     */
    function form_get_errors() {
      $form = form_set_error();
      if (!empty($form)) {
        return $form;
      }
    }
    
    /**
     * Return the error message filed against the form with the specified name.
     */
    function form_get_error($element) {
      $form = form_set_error();
      $key = $element['#parents'][0];
      if (isset($form[$key])) {
        return $form[$key];
      }
      $key = implode('][', $element['#parents']);
      if (isset($form[$key])) {
        return $form[$key];
      }
    }
    
    /**
     * Flag an element as having an error.
     */
    function form_error(&$element, $message = '') {
      form_set_error(implode('][', $element['#parents']), $message);
    }
    
    /**
     * Walk through the structured form array, adding any required
     * properties to each element and mapping the incoming $_POST
     * data to the proper elements.
     *
     * @param $form_id
     *   A unique string identifying the form for validation, submission,
     *   theming, and hook_form_alter functions.
     * @param $form
     *   An associative array containing the structure of the form.
     * @param $form_state
     *   A keyed array containing the current state of the form. In this
     *   context, it is used to accumulate information about which button
     *   was clicked when the form was submitted, as well as the sanitized
     *   $_POST data.
     */
    function form_builder($form_id, $form, &$form_state) {
      static $complete_form, $cache;
    
      // Initialize as unprocessed.
      $form['#processed'] = FALSE;
    
      /* Use element defaults */
      if ((!empty($form['#type'])) && ($info = _element_info($form['#type']))) {
        // Overlay $info onto $form, retaining preexisting keys in $form.
        $form += $info;
      }
    
      if (isset($form['#type']) && $form['#type'] == 'form') {
        $complete_form = $form;
        if (!empty($form['#programmed'])) {
          $form_state['submitted'] = TRUE;
        }
      }
    
      if (isset($form['#input']) && $form['#input']) {
        _form_builder_handle_input_element($form_id, $form, $form_state, $complete_form);
      }
      $form['#defaults_loaded'] = TRUE;
    
      // We start off assuming all form elements are in the correct order.
      $form['#sorted'] = TRUE;
    
      // Recurse through all child elements.
      $count = 0;
      foreach (element_children($form) as $key) {
        $form[$key]['#post'] = $form['#post'];
        $form[$key]['#programmed'] = $form['#programmed'];
        // Don't squash an existing tree value.
        if (!isset($form[$key]['#tree'])) {
          $form[$key]['#tree'] = $form['#tree'];
        }
    
        // Deny access to child elements if parent is denied.
        if (isset($form['#access']) && !$form['#access']) {
          $form[$key]['#access'] = FALSE;
        }
    
        // Don't squash existing parents value.
        if (!isset($form[$key]['#parents'])) {
          // Check to see if a tree of child elements is present. If so,
          // continue down the tree if required.
          $form[$key]['#parents'] = $form[$key]['#tree'] && $form['#tree'] ? array_merge($form['#parents'], array($key)) : array($key);
          $array_parents = isset($form['#array_parents']) ? $form['#array_parents'] : array();
          $array_parents[] = $key;
          $form[$key]['#array_parents'] = $array_parents;
        }
    
        // Assign a decimal placeholder weight to preserve original array order.
        if (!isset($form[$key]['#weight'])) {
          $form[$key]['#weight'] = $count/1000;
        }
        else {
          // If one of the child elements has a weight then we will need to sort
          // later.
          unset($form['#sorted']);
        }
        $form[$key] = form_builder($form_id, $form[$key], $form_state);
        $count++;
      }
    
      // The #after_build flag allows any piece of a form to be altered
      // after normal input parsing has been completed.
      if (isset($form['#after_build']) && !isset($form['#after_build_done'])) {
        foreach ($form['#after_build'] as $function) {
          $form = $function($form, $form_state);
          $form['#after_build_done'] = TRUE;
        }
      }
    
      // Now that we've processed everything, we can go back to handle the funky
      // Internet Explorer button-click scenario.
      _form_builder_ie_cleanup($form, $form_state);
    
      // After handling the special IE case, we no longer need the buttons collection.
      unset($form_state['buttons']);
    
      // If some callback set #cache, we need to flip a static flag so later it
      // can be found.
      if (isset($form['#cache'])) {
        $cache = $form['#cache'];
      }
      // We are on the top form, we can copy back #cache if it's set.
      if (isset($form['#type']) && $form['#type'] == 'form' && isset($cache)) {
        $form['#cache'] = TRUE;
      }
      return $form;
    }
    
    /**
     * Populate the #value and #name properties of input elements so they
     * can be processed and rendered. Also, execute any #process handlers
     * attached to a specific element.
     */
    function _form_builder_handle_input_element($form_id, &$form, &$form_state, $complete_form) {
      if (!isset($form['#name'])) {
        $name = array_shift($form['#parents']);
        $form['#name'] = $name;
        if ($form['#type'] == 'file') {
          // To make it easier to handle $_FILES in file.inc, we place all
          // file fields in the 'files' array. Also, we do not support
          // nested file names.
          $form['#name'] = 'files['. $form['#name'] .']';
        }
        elseif (count($form['#parents'])) {
          $form['#name'] .= '['. implode('][', $form['#parents']) .']';
        }
        array_unshift($form['#parents'], $name);
      }
      if (!isset($form['#id'])) {
        $form['#id'] = form_clean_id('edit-'. implode('-', $form['#parents']));
      }
    
      unset($edit);
      if (!empty($form['#disabled'])) {
        $form['#attributes']['disabled'] = 'disabled';
      }
    
      if (!isset($form['#value']) && !array_key_exists('#value', $form)) {
        $function = !empty($form['#value_callback']) ? $form['#value_callback'] : 'form_type_'. $form['#type'] .'_value';
        if (($form['#programmed']) || ((!isset($form['#access']) || $form['#access']) && isset($form['#post']) && (isset($form['#post']['form_id']) && $form['#post']['form_id'] == $form_id))) {
          $edit = $form['#post'];
          foreach ($form['#parents'] as $parent) {
            $edit = isset($edit[$parent]) ? $edit[$parent] : NULL;
          }
          if (!$form['#programmed'] || isset($edit)) {
            // Call #type_value to set the form value;
            if (function_exists($function)) {
              $form['#value'] = $function($form, $edit);
            }
            if (!isset($form['#value']) && isset($edit)) {
              $form['#value'] = $edit;
            }
          }
          // Mark all posted values for validation.
          if (isset($form['#value']) || (isset($form['#required']) && $form['#required'])) {
            $form['#needs_validation'] = TRUE;
          }
        }
        // Load defaults.
        if (!isset($form['#value'])) {
          // Call #type_value without a second argument to request default_value handling.
          if (function_exists($function)) {
            $form['#value'] = $function($form);
          }
          // Final catch. If we haven't set a value yet, use the explicit default value.
          if (!isset($form['#value'])) {
            $form['#value'] = isset($form['#default_value']) ? $form['#default_value'] : '';
          }
        }
      }
    
      // Determine which button (if any) was clicked to submit the form.
      // We compare the incoming values with the buttons defined in the form,
      // and flag the one that matches. We have to do some funky tricks to
      // deal with Internet Explorer's handling of single-button forms, though.
      if (!empty($form['#post']) && isset($form['#executes_submit_callback'])) {
        // First, accumulate a collection of buttons, divided into two bins:
        // those that execute full submit callbacks and those that only validate.
        $button_type = $form['#executes_submit_callback'] ? 'submit' : 'button';
        $form_state['buttons'][$button_type][] = $form;
    
        if (_form_button_was_clicked($form)) {
          $form_state['submitted'] = $form_state['submitted'] || $form['#executes_submit_callback'];
    
          // In most cases, we want to use form_set_value() to manipulate
          // the global variables. In this special case, we want to make sure that
          // the value of this element is listed in $form_variables under 'op'.
          $form_state['values'][$form['#name']] = $form['#value'];
          $form_state['clicked_button'] = $form;
    
          if (isset($form['#validate'])) {
            $form_state['validate_handlers'] = $form['#validate'];
          }
          if (isset($form['#submit'])) {
            $form_state['submit_handlers'] = $form['#submit'];
          }
        }
      }
      // Allow for elements to expand to multiple elements, e.g., radios,
      // checkboxes and files.
      if (isset($form['#process']) && !$form['#processed']) {
        foreach ($form['#process'] as $process) {
          if (function_exists($process)) {
            $form = $process($form, isset($edit) ? $edit : NULL, $form_state, $complete_form);
          }
        }
        $form['#processed'] = TRUE;
      }
      form_set_value($form, $form['#value'], $form_state);
    }
    
    /**
     * Helper function to handle the sometimes-convoluted logic of button
     * click detection.
     *
     * In Internet Explorer, if ONLY one submit button is present, AND the
     * enter key is used to submit the form, no form value is sent for it
     * and we'll never detect a match. That special case is handled by
     * _form_builder_ie_cleanup().
     */
    function _form_button_was_clicked($form) {
      // First detect normal 'vanilla' button clicks. Traditionally, all
      // standard buttons on a form share the same name (usually 'op'),
      // and the specific return value is used to determine which was
      // clicked. This ONLY works as long as $form['#name'] puts the
      // value at the top level of the tree of $_POST data.
      if (isset($form['#post'][$form['#name']]) && $form['#post'][$form['#name']] == $form['#value']) {
        return TRUE;
      }
      // When image buttons are clicked, browsers do NOT pass the form element
      // value in $_POST. Instead they pass an integer representing the
      // coordinates of the click on the button image. This means that image
      // buttons MUST have unique $form['#name'] values, but the details of
      // their $_POST data should be ignored.
      elseif (!empty($form['#has_garbage_value']) && isset($form['#value']) && $form['#value'] !== '') {
        return TRUE;
      }
      return FALSE;
    }
    
    /**
     * In IE, if only one submit button is present, AND the enter key is
     * used to submit the form, no form value is sent for it and our normal
     * button detection code will never detect a match. We call this
     * function after all other button-detection is complete to check
     * for the proper conditions, and treat the single button on the form
     * as 'clicked' if they are met.
     */
    function _form_builder_ie_cleanup($form, &$form_state) {
      // Quick check to make sure we're always looking at the full form
      // and not a sub-element.
      if (!empty($form['#type']) && $form['#type'] == 'form') {
        // If we haven't recognized a submission yet, and there's a single
        // submit button, we know that we've hit the right conditions. Grab
        // the first one and treat it as the clicked button.
        if (empty($form_state['submitted']) && !empty($form_state['buttons']['submit']) && empty($form_state['buttons']['button'])) {
          $button = $form_state['buttons']['submit'][0];
    
          // Set up all the $form_state information that would have been
          // populated had the button been recognized earlier.
          $form_state['submitted'] = TRUE;
          $form_state['submit_handlers'] = empty($button['#submit']) ? NULL : $button['#submit'];
          $form_state['validate_handlers'] = empty($button['#validate']) ? NULL : $button['#validate'];
          $form_state['values'][$button['#name']] = $button['#value'];
          $form_state['clicked_button'] = $button;
        }
      }
    }
    
    /**
     * Helper function to determine the value for an image button form element.
     *
     * @param $form
     *   The form element whose value is being populated.
     * @param $edit
     *   The incoming POST data to populate the form element. If this is FALSE,
     *   the element's default value should be returned.
     * @return
     *   The data that will appear in the $form_state['values'] collection
     *   for this element. Return nothing to use the default.
     */
    function form_type_image_button_value($form, $edit = FALSE) {
      if ($edit !== FALSE) {
        if (!empty($edit)) {
          // If we're dealing with Mozilla or Opera, we're lucky. It will
          // return a proper value, and we can get on with things.
          return $form['#return_value'];
        }
        else {
          // Unfortunately, in IE we never get back a proper value for THIS
          // form element. Instead, we get back two split values: one for the
          // X and one for the Y coordinates on which the user clicked the
          // button. We'll find this element in the #post data, and search
          // in the same spot for its name, with '_x'.
          $post = $form['#post'];
          foreach (split('\[', $form['#name']) as $element_name) {
            // chop off the ] that may exist.
            if (substr($element_name, -1) == ']') {
              $element_name = substr($element_name, 0, -1);
            }
    
            if (!isset($post[$element_name])) {
              if (isset($post[$element_name .'_x'])) {
                return $form['#return_value'];
              }
              return NULL;
            }
            $post = $array[$element_name];
          }
          return $form['#return_value'];
        }
      }
    }
    
    /**
     * Helper function to determine the value for a checkbox form element.
     *
     * @param $form
     *   The form element whose value is being populated.
     * @param $edit
     *   The incoming POST data to populate the form element. If this is FALSE,
     *   the element's default value should be returned.
     * @return
     *   The data that will appear in the $form_state['values'] collection
     *   for this element. Return nothing to use the default.
     */
    function form_type_checkbox_value($form, $edit = FALSE) {
      if ($edit !== FALSE) {
        return !empty($edit) ? $form['#return_value'] : 0;
      }
    }
    
    /**
     * Helper function to determine the value for a checkboxes form element.
     *
     * @param $form
     *   The form element whose value is being populated.
     * @param $edit
     *   The incoming POST data to populate the form element. If this is FALSE,
     *   the element's default value should be returned.
     * @return
     *   The data that will appear in the $form_state['values'] collection
     *   for this element. Return nothing to use the default.
     */
    function form_type_checkboxes_value($form, $edit = FALSE) {
      if ($edit === FALSE) {
        $value = array();
        $form += array('#default_value' => array());
        foreach ($form['#default_value'] as $key) {
          $value[$key] = 1;
        }
        return $value;
      }
      elseif (!isset($edit)) {
        return array();
      }
    }
    
    /**
     * Helper function to determine the value for a password_confirm form
     * element.
     *
     * @param $form
     *   The form element whose value is being populated.
     * @param $edit
     *   The incoming POST data to populate the form element. If this is FALSE,
     *   the element's default value should be returned.
     * @return
     *   The data that will appear in the $form_state['values'] collection
     *   for this element. Return nothing to use the default.
     */
    function form_type_password_confirm_value($form, $edit = FALSE) {
      if ($edit === FALSE) {
        $form += array('#default_value' => array());
        return $form['#default_value'] + array('pass1' => '', 'pass2' => '');
      }
    }
    
    /**
     * Helper function to determine the value for a select form element.
     *
     * @param $form
     *   The form element whose value is being populated.
     * @param $edit
     *   The incoming POST data to populate the form element. If this is FALSE,
     *   the element's default value should be returned.
     * @return
     *   The data that will appear in the $form_state['values'] collection
     *   for this element. Return nothing to use the default.
     */
    function form_type_select_value($form, $edit = FALSE) {
      if ($edit !== FALSE) {
        if (isset($form['#multiple']) && $form['#multiple']) {
          return (is_array($edit)) ? drupal_map_assoc($edit) : array();
        }
        else {
          return $edit;
        }
      }
    }
    
    /**
     * Helper function to determine the value for a textfield form element.
     *
     * @param $form
     *   The form element whose value is being populated.
     * @param $edit
     *   The incoming POST data to populate the form element. If this is FALSE,
     *   the element's default value should be returned.
     * @return
     *   The data that will appear in the $form_state['values'] collection
     *   for this element. Return nothing to use the default.
     */
    function form_type_textfield_value($form, $edit = FALSE) {
      if ($edit !== FALSE) {
        // Equate $edit to the form value to ensure it's marked for
        // validation.
        return str_replace(array("\r", "\n"), '', $edit);
      }
    }
    
    /**
     * Helper function to determine the value for form's token value.
     *
     * @param $form
     *   The form element whose value is being populated.
     * @param $edit
     *   The incoming POST data to populate the form element. If this is FALSE,
     *   the element's default value should be returned.
     * @return
     *   The data that will appear in the $form_state['values'] collection
     *   for this element. Return nothing to use the default.
     */
    function form_type_token_value($form, $edit = FALSE) {
      if ($edit !== FALSE) {
        return (string)$edit;
      }
    }
    
    /**
     * Use this function to make changes to form values in the form validate
     * phase, so they will be available in the submit phase in $form_state.
     *
     * Specifically, if $form['#parents'] is array('foo', 'bar')
     * and $value is 'baz' then this function will make
     * $form_state['values']['foo']['bar'] to be 'baz'.
     *
     * @param $form
     *   The form item. Keys used: #parents, #value
     * @param $value
     *   The value for the form item.
     */
    function form_set_value($form, $value, &$form_state) {
      _form_set_value($form_state['values'], $form, $form['#parents'], $value);
    }
    
    /**
     * Helper function for form_set_value().
     *
     * We iterate over $parents and create nested arrays for them
     * in $form_state['values'] if needed. Then we insert the value into
     * the right array.
     */
    function _form_set_value(&$form_values, $form, $parents, $value) {
      $parent = array_shift($parents);
      if (empty($parents)) {
        $form_values[$parent] = $value;
      }
      else {
        if (!isset($form_values[$parent])) {
          $form_values[$parent] = array();
        }
        _form_set_value($form_values[$parent], $form, $parents, $value);
      }
    }
    
    /**
     * Retrieve the default properties for the defined element type.
     */
    function _element_info($type, $refresh = NULL) {
      static $cache;
    
      $basic_defaults = array(
        '#description' => NULL,
        '#attributes' => array(),
        '#required' => FALSE,
        '#tree' => FALSE,
        '#parents' => array()
      );
      if (!isset($cache) || $refresh) {
        $cache = array();
        foreach (module_implements('elements') as $module) {
          $elements = module_invoke($module, 'elements');
          if (isset($elements) && is_array($elements)) {
            $cache = array_merge_recursive($cache, $elements);
          }
        }
        if (sizeof($cache)) {
          foreach ($cache as $element_type => $info) {
            $cache[$element_type] = array_merge_recursive($basic_defaults, $info);
          }
        }
      }
    
      return $cache[$type];
    }
    
    function form_options_flatten($array, $reset = TRUE) {
      static $return;
    
      if ($reset) {
        $return = array();
      }
    
      foreach ($array as $key => $value) {
        if (is_object($value)) {
          form_options_flatten($value->option, FALSE);
        }
        else if (is_array($value)) {
          form_options_flatten($value, FALSE);
        }
        else {
          $return[$key] = 1;
        }
      }
    
      return $return;
    }
    
    /**
     * Format a dropdown menu or scrolling selection box.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used: title, value, options, description, extra, multiple, required
     * @return
     *   A themed HTML string representing the form element.
     *
     * @ingroup themeable
     *
     * It is possible to group options together; to do this, change the format of
     * $options to an associative array in which the keys are group labels, and the
     * values are associative arrays in the normal $options format.
     */
    function theme_select($element) {
      $select = '';
      $size = $element['#size'] ? ' size="'. $element['#size'] .'"' : '';
      _form_set_class($element, array('form-select'));
      $multiple = $element['#multiple'];
      return theme('form_element', $element, '<select name="'. $element['#name'] .''. ($multiple ? '[]' : '') .'"'. ($multiple ? ' multiple="multiple" ' : '') . drupal_attributes($element['#attributes']) .' id="'. $element['#id'] .'" '. $size .'>'. form_select_options($element) .'</select>');
    }
    
    function form_select_options($element, $choices = NULL) {
      if (!isset($choices)) {
        $choices = $element['#options'];
      }
      // array_key_exists() accommodates the rare event where $element['#value'] is NULL.
      // isset() fails in this situation.
      $value_valid = isset($element['#value']) || array_key_exists('#value', $element);
      $value_is_array = is_array($element['#value']);
      $options = '';
      foreach ($choices as $key => $choice) {
        if (is_array($choice)) {
          $options .= '<optgroup label="'. $key .'">';
          $options .= form_select_options($element, $choice);
          $options .= '</optgroup>';
        }
        elseif (is_object($choice)) {
          $options .= form_select_options($element, $choice->option);
        }
        else {
          $key = (string)$key;
          if ($value_valid && (!$value_is_array && (string)$element['#value'] === $key || ($value_is_array && in_array($key, $element['#value'])))) {
            $selected = ' selected="selected"';
          }
          else {
            $selected = '';
          }
          $options .= '<option value="'. check_plain($key) .'"'. $selected .'>'. check_plain($choice) .'</option>';
        }
      }
      return $options;
    }
    
    /**
     * Traverses a select element's #option array looking for any values
     * that hold the given key. Returns an array of indexes that match.
     *
     * This function is useful if you need to modify the options that are
     * already in a form element; for example, to remove choices which are
     * not valid because of additional filters imposed by another module.
     * One example might be altering the choices in a taxonomy selector.
     * To correctly handle the case of a multiple hierarchy taxonomy,
     * #options arrays can now hold an array of objects, instead of a
     * direct mapping of keys to labels, so that multiple choices in the
     * selector can have the same key (and label). This makes it difficult
     * to manipulate directly, which is why this helper function exists.
     *
     * This function does not support optgroups (when the elements of the
     * #options array are themselves arrays), and will return FALSE if
     * arrays are found. The caller must either flatten/restore or
     * manually do their manipulations in this case, since returning the
     * index is not sufficient, and supporting this would make the
     * "helper" too complicated and cumbersome to be of any help.
     *
     * As usual with functions that can return array() or FALSE, do not
     * forget to use === and !== if needed.
     *
     * @param $element
     *   The select element to search.
     * @param $key
     *   The key to look for.
     * @return
     *   An array of indexes that match the given $key. Array will be
     *   empty if no elements were found. FALSE if optgroups were found.
     */
    function form_get_options($element, $key) {
      $keys = array();
      foreach ($element['#options'] as $index => $choice) {
        if (is_array($choice)) {
          return FALSE;
        }
        else if (is_object($choice)) {
          if (isset($choice->option[$key])) {
            $keys[] = $index;
          }
        }
        else if ($index == $key) {
          $keys[] = $index;
        }
      }
      return $keys;
    }
    
    /**
     * Format a group of form items.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used: attributes, title, value, description, children, collapsible, collapsed
     * @return
     *   A themed HTML string representing the form item group.
     *
     * @ingroup themeable
     */
    function theme_fieldset($element) {
      if ($element['#collapsible']) {
        drupal_add_js('misc/collapse.js');
    
        if (!isset($element['#attributes']['class'])) {
          $element['#attributes']['class'] = '';
        }
    
        $element['#attributes']['class'] .= ' collapsible';
        if ($element['#collapsed']) {
         $element['#attributes']['class'] .= ' collapsed';
        }
      }
    
      return '<fieldset'. drupal_attributes($element['#attributes']) .'>'. ($element['#title'] ? '<legend>'. $element['#title'] .'</legend>' : '') . (isset($element['#description']) && $element['#description'] ? '<div class="description">'. $element['#description'] .'</div>' : '') . (!empty($element['#children']) ? $element['#children'] : '') . $element['#value'] ."</fieldset>\n";
    }
    
    /**
     * Format a radio button.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used: required, return_value, value, attributes, title, description
     * @return
     *   A themed HTML string representing the form item group.
     *
     * @ingroup themeable
     */
    function theme_radio($element) {
      _form_set_class($element, array('form-radio'));
      $output = '<input type="radio" ';
      $output .= 'name="'. $element['#name'] .'" ';
      $output .= 'value="'. $element['#return_value'] .'" ';
      $output .= (check_plain($element['#value']) == $element['#return_value']) ? ' checked="checked" ' : ' ';
      $output .= drupal_attributes($element['#attributes']) .' />';
      if (!is_null($element['#title'])) {
        $output = '<label class="option">'. $output .' '. $element['#title'] .'</label>';
      }
    
      unset($element['#title']);
      return theme('form_element', $element, $output);
    }
    
    /**
     * Format a set of radio buttons.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used: title, value, options, description, required and attributes.
     * @return
     *   A themed HTML string representing the radio button set.
     *
     * @ingroup themeable
     */
    function theme_radios($element) {
      $class = 'form-radios';
      if (isset($element['#attributes']['class'])) {
        $class .= ' '. $element['#attributes']['class'];
      }
      $element['#children'] = '<div class="'. $class .'">'. (!empty($element['#children']) ? $element['#children'] : '') .'</div>';
      if ($element['#title'] || $element['#description']) {
        unset($element['#id']);
        return theme('form_element', $element, $element['#children']);
      }
      else {
        return $element['#children'];
      }
    }
    
    /**
     * Format a password_confirm item.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used: title, value, id, required, error.
     * @return
     *   A themed HTML string representing the form item.
     *
     * @ingroup themeable
     */
    function theme_password_confirm($element) {
      return theme('form_element', $element, $element['#children']);
    }
    
    /*
     * Expand a password_confirm field into two text boxes.
     */
    function expand_password_confirm($element) {
      $element['pass1'] =  array(
        '#type' => 'password',
        '#title' => t('Password'),
        '#value' => empty($element['#value']) ? NULL : $element['#value']['pass1'],
        '#required' => $element['#required'],
        '#attributes' => array('class' => 'password-field'),
      );
      $element['pass2'] =  array(
        '#type' => 'password',
        '#title' => t('Confirm password'),
        '#value' => empty($element['#value']) ? NULL : $element['#value']['pass2'],
        '#required' => $element['#required'],
        '#attributes' => array('class' => 'password-confirm'),
      );
      $element['#element_validate'] = array('password_confirm_validate');
      $element['#tree'] = TRUE;
    
      if (isset($element['#size'])) {
        $element['pass1']['#size'] = $element['pass2']['#size'] = $element['#size'];
      }
    
      return $element;
    }
    
    /**
     * Validate password_confirm element.
     */
    function password_confirm_validate($form, &$form_state) {
      $pass1 = trim($form['pass1']['#value']);
      if (!empty($pass1)) {
        $pass2 = trim($form['pass2']['#value']);
        if ($pass1 != $pass2) {
          form_error($form, t('The specified passwords do not match.'));
        }
      }
      elseif ($form['#required'] && !empty($form['#post'])) {
        form_error($form, t('Password field is required.'));
      }
    
      // Password field must be converted from a two-element array into a single
      // string regardless of validation results.
      form_set_value($form['pass1'], NULL, $form_state);
      form_set_value($form['pass2'], NULL, $form_state);
      form_set_value($form, $pass1, $form_state);
    
      return $form;
    
    }
    
    /**
     * Format a date selection element.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used: title, value, options, description, required and attributes.
     * @return
     *   A themed HTML string representing the date selection boxes.
     *
     * @ingroup themeable
     */
    function theme_date($element) {
      return theme('form_element', $element, '<div class="container-inline">'. $element['#children'] .'</div>');
    }
    
    /**
     * Roll out a single date element.
     */
    function expand_date($element) {
      // Default to current date
      if (empty($element['#value'])) {
        $element['#value'] = array('day' => format_date(time(), 'custom', 'j'),
                                'month' => format_date(time(), 'custom', 'n'),
                                'year' => format_date(time(), 'custom', 'Y'));
      }
    
      $element['#tree'] = TRUE;
    
      // Determine the order of day, month, year in the site's chosen date format.
      $format = variable_get('date_format_short', 'm/d/Y - H:i');
      $sort = array();
      $sort['day'] = max(strpos($format, 'd'), strpos($format, 'j'));
      $sort['month'] = max(strpos($format, 'm'), strpos($format, 'M'));
      $sort['year'] = strpos($format, 'Y');
      asort($sort);
      $order = array_keys($sort);
    
      // Output multi-selector for date.
      foreach ($order as $type) {
        switch ($type) {
          case 'day':
            $options = drupal_map_assoc(range(1, 31));
            break;
          case 'month':
            $options = drupal_map_assoc(range(1, 12), 'map_month');
            break;
          case 'year':
            $options = drupal_map_assoc(range(1900, 2050));
            break;
        }
        $parents = $element['#parents'];
        $parents[] = $type;
        $element[$type] = array(
          '#type' => 'select',
          '#value' => $element['#value'][$type],
          '#attributes' => $element['#attributes'],
          '#options' => $options,
        );
      }
    
      return $element;
    }
    
    /**
     * Validates the date type to stop dates like February 30, 2006.
     */
    function date_validate($form) {
      if (!checkdate($form['#value']['month'], $form['#value']['day'], $form['#value']['year'])) {
        form_error($form, t('The specified date is invalid.'));
      }
    }
    
    /**
     * Helper function for usage with drupal_map_assoc to display month names.
     */
    function map_month($month) {
      return format_date(gmmktime(0, 0, 0, $month, 2, 1970), 'custom', 'M', 0);
    }
    
    /**
     * If no default value is set for weight select boxes, use 0.
     */
    function weight_value(&$form) {
      if (isset($form['#default_value'])) {
        $form['#value'] = $form['#default_value'];
      }
      else {
        $form['#value'] = 0;
      }
    }
    
    /**
     * Roll out a single radios element to a list of radios,
     * using the options array as index.
     */
    function expand_radios($element) {
      if (count($element['#options']) > 0) {
        foreach ($element['#options'] as $key => $choice) {
          if (!isset($element[$key])) {
            // Generate the parents as the autogenerator does, so we will have a
            // unique id for each radio button.
            $parents_for_id = array_merge($element['#parents'], array($key));
            $element[$key] = array(
              '#type' => 'radio',
              '#title' => $choice,
              '#return_value' => check_plain($key),
              '#default_value' => isset($element['#default_value']) ? $element['#default_value'] : NULL,
              '#attributes' => $element['#attributes'],
              '#parents' => $element['#parents'],
              '#id' => form_clean_id('edit-'. implode('-', $parents_for_id)),
            );
          }
        }
      }
      return $element;
    }
    
    /**
     * Add AHAH information about a form element to the page to communicate with
     * javascript. If #ahah[path] is set on an element, this additional javascript is
     * added to the page header to attach the AHAH behaviors. See ahah.js for more
     * information.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used: ahah_event, ahah_path, ahah_wrapper, ahah_parameters,
     *   ahah_effect.
     * @return
     *   None. Additional code is added to the header of the page using
     *   drupal_add_js.
     */
    function form_expand_ahah($element) {
      static $js_added = array();
      // Add a reasonable default event handler if none specified.
      if (isset($element['#ahah']['path']) && !isset($element['#ahah']['event'])) {
        switch ($element['#type']) {
          case 'submit':
          case 'button':
          case 'image_button':
            $element['#ahah']['event'] = 'click';
            break;
          case 'password':
          case 'textfield':
          case 'textarea':
            $element['#ahah']['event'] = 'blur';
            break;
          case 'radio':
          case 'checkbox':
          case 'select':
            $element['#ahah']['event'] = 'change';
            break;
        }
      }
    
      // Adding the same javascript settings twice will cause a recursion error,
      // we avoid the problem by checking if the javascript has already been added.
      if (isset($element['#ahah']['path']) && isset($element['#ahah']['event']) && !isset($js_added[$element['#id']])) {
        drupal_add_js('misc/jquery.form.js');
        drupal_add_js('misc/ahah.js');
    
        $ahah_binding = array(
          'url'      => url($element['#ahah']['path']),
          'event'    => $element['#ahah']['event'],
          'wrapper'  => empty($element['#ahah']['wrapper']) ? NULL : $element['#ahah']['wrapper'],
          'selector' => empty($element['#ahah']['selector']) ? '#'. $element['#id'] : $element['#ahah']['selector'],
          'effect'   => empty($element['#ahah']['effect']) ? 'none' : $element['#ahah']['effect'],
          'method'   => empty($element['#ahah']['method']) ? 'replace' : $element['#ahah']['method'],
          'progress' => empty($element['#ahah']['progress']) ? array('type' => 'throbber') : $element['#ahah']['progress'],
          'button'   => $element['#type'] == 'submit' ? array($element['#name'] => $element['#value']) : FALSE,
        );
    
        // Convert a simple #ahah[progress] type string into an array.
        if (is_string($ahah_binding['progress'])) {
          $ahah_binding['progress'] = array('type' => $ahah_binding['progress']);
        }
        // Change progress path to a full url.
        if (isset($ahah_binding['progress']['path'])) {
          $ahah_binding['progress']['url'] = url($ahah_binding['progress']['path']);
        }
    
        // Add progress.js if we're doing a bar display.
        if ($ahah_binding['progress']['type'] == 'bar') {
          drupal_add_js('misc/progress.js');
        }
    
        drupal_add_js(array('ahah' => array($element['#id'] => $ahah_binding)), 'setting');
    
        $js_added[$element['#id']] = TRUE;
        $element['#cache'] = TRUE;
      }
      return $element;
    }
    
    /**
     * Format a form item.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used:  title, value, description, required, error
     * @return
     *   A themed HTML string representing the form item.
     *
     * @ingroup themeable
     */
    function theme_item($element) {
      return theme('form_element', $element, $element['#value'] . (!empty($element['#children']) ? $element['#children'] : ''));
    }
    
    /**
     * Format a checkbox.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used:  title, value, return_value, description, required
     * @return
     *   A themed HTML string representing the checkbox.
     *
     * @ingroup themeable
     */
    function theme_checkbox($element) {
      _form_set_class($element, array('form-checkbox'));
      $checkbox = '<input ';
      $checkbox .= 'type="checkbox" ';
      $checkbox .= 'name="'. $element['#name'] .'" ';
      $checkbox .= 'id="'. $element['#id'] .'" ' ;
      $checkbox .= 'value="'. $element['#return_value'] .'" ';
      $checkbox .= $element['#value'] ? ' checked="checked" ' : ' ';
      $checkbox .= drupal_attributes($element['#attributes']) .' />';
    
      if (!is_null($element['#title'])) {
        $checkbox = '<label class="option">'. $checkbox .' '. $element['#title'] .'</label>';
      }
    
      unset($element['#title']);
      return theme('form_element', $element, $checkbox);
    }
    
    /**
     * Format a set of checkboxes.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     * @return
     *   A themed HTML string representing the checkbox set.
     *
     * @ingroup themeable
     */
    function theme_checkboxes($element) {
      $class = 'form-checkboxes';
      if (isset($element['#attributes']['class'])) {
        $class .= ' '. $element['#attributes']['class'];
      }
      $element['#children'] = '<div class="'. $class .'">'. (!empty($element['#children']) ? $element['#children'] : '') .'</div>';
      if ($element['#title'] || $element['#description']) {
        unset($element['#id']);
        return theme('form_element', $element, $element['#children']);
      }
      else {
        return $element['#children'];
      }
    }
    
    function expand_checkboxes($element) {
      $value = is_array($element['#value']) ? $element['#value'] : array();
      $element['#tree'] = TRUE;
      if (count($element['#options']) > 0) {
        if (!isset($element['#default_value']) || $element['#default_value'] == 0) {
          $element['#default_value'] = array();
        }
        foreach ($element['#options'] as $key => $choice) {
          if (!isset($element[$key])) {
            $element[$key] = array('#type' => 'checkbox', '#processed' => TRUE, '#title' => $choice, '#return_value' => $key, '#default_value' => isset($value[$key]), '#attributes' => $element['#attributes']);
          }
        }
      }
      return $element;
    }
    
    /**
     * Theme a form submit button.
     *
     * @ingroup themeable
     */
    function theme_submit($element) {
      return theme('button', $element);
    }
    
    /**
     * Theme a form button.
     *
     * @ingroup themeable
     */
    function theme_button($element) {
      // Make sure not to overwrite classes.
      if (isset($element['#attributes']['class'])) {
        $element['#attributes']['class'] = 'form-'. $element['#button_type'] .' '. $element['#attributes']['class'];
      }
      else {
        $element['#attributes']['class'] = 'form-'. $element['#button_type'];
      }
    
      return '<input type="submit" '. (empty($element['#name']) ? '' : 'name="'. $element['#name'] .'" ') .'id="'. $element['#id'] .'" value="'. check_plain($element['#value']) .'" '. drupal_attributes($element['#attributes']) ." />\n";
    }
    
    /**
     * Theme a form image button.
     *
     * @ingroup themeable
     */
    function theme_image_button($element) {
      // Make sure not to overwrite classes.
      if (isset($element['#attributes']['class'])) {
        $element['#attributes']['class'] = 'form-'. $element['#button_type'] .' '. $element['#attributes']['class'];
      }
      else {
        $element['#attributes']['class'] = 'form-'. $element['#button_type'];
      }
    
      return '<input type="image" name="'. $element['#name'] .'" '.
        (!empty($element['#value']) ? ('value="'. check_plain($element['#value']) .'" ') : '') .
        'id="'. $element['#id'] .'" '.
        drupal_attributes($element['#attributes']) .
        ' src="'. base_path() . $element['#src'] .'" '.
        (!empty($element['#title']) ? 'alt="'. check_plain($element['#title']) .'" title="'. check_plain($element['#title']) .'" ' : '' ) .
        "/>\n";
    }
    
    /**
     * Format a hidden form field.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used:  value, edit
     * @return
     *   A themed HTML string representing the hidden form field.
     *
     * @ingroup themeable
     */
    function theme_hidden($element) {
      return '<input type="hidden" name="'. $element['#name'] .'" id="'. $element['#id'] .'" value="'. check_plain($element['#value']) ."\" ". drupal_attributes($element['#attributes']) ." />\n";
    }
    
    /**
     * Format a form token.
     *
     * @ingroup themeable
     */
    function theme_token($element) {
      return theme('hidden', $element);
    }
    
    /**
     * Format a textfield.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used:  title, value, description, size, maxlength, required, attributes autocomplete_path
     * @return
     *   A themed HTML string representing the textfield.
     *
     * @ingroup themeable
     */
    function theme_textfield($element) {
      $size = empty($element['#size']) ? '' : ' size="'. $element['#size'] .'"';
      $maxlength = empty($element['#maxlength']) ? '' : ' maxlength="'. $element['#maxlength'] .'"';
      $class = array('form-text');
      $extra = '';
      $output = '';
    
      if ($element['#autocomplete_path']) {
        drupal_add_js('misc/autocomplete.js');
        $class[] = 'form-autocomplete';
        $extra =  '<input class="autocomplete" type="hidden" id="'. $element['#id'] .'-autocomplete" value="'. check_url(url($element['#autocomplete_path'], array('absolute' => TRUE))) .'" disabled="disabled" />';
      }
      _form_set_class($element, $class);
    
      if (isset($element['#field_prefix'])) {
        $output .= '<span class="field-prefix">'. $element['#field_prefix'] .'</span> ';
      }
    
      $output .= '<input type="text"'. $maxlength .' name="'. $element['#name'] .'" id="'. $element['#id'] .'"'. $size .' value="'. check_plain($element['#value']) .'"'. drupal_attributes($element['#attributes']) .' />';
    
      if (isset($element['#field_suffix'])) {
        $output .= ' <span class="field-suffix">'. $element['#field_suffix'] .'</span>';
      }
    
      return theme('form_element', $element, $output) . $extra;
    }
    
    /**
     * Format a form.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used: action, method, attributes, children
     * @return
     *   A themed HTML string representing the form.
     *
     * @ingroup themeable
     */
    function theme_form($element) {
      // Anonymous div to satisfy XHTML compliance.
      $action = $element['#action'] ? 'action="'. check_url($element['#action']) .'" ' : '';
      return '<form '. $action .' accept-charset="UTF-8" method="'. $element['#method'] .'" id="'. $element['#id'] .'"'. drupal_attributes($element['#attributes']) .">\n<div>". $element['#children'] ."\n</div></form>\n";
    }
    
    /**
     * Format a textarea.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used: title, value, description, rows, cols, required, attributes
     * @return
     *   A themed HTML string representing the textarea.
     *
     * @ingroup themeable
     */
    function theme_textarea($element) {
      $class = array('form-textarea');
    
      // Add teaser behavior (must come before resizable)
      if (!empty($element['#teaser'])) {
        drupal_add_js('misc/teaser.js');
        // Note: arrays are merged in drupal_get_js().
        drupal_add_js(array('teaserCheckbox' => array($element['#id'] => $element['#teaser_checkbox'])), 'setting');
        drupal_add_js(array('teaser' => array($element['#id'] => $element['#teaser'])), 'setting');
        $class[] = 'teaser';
      }
    
      // Add resizable behavior
      if ($element['#resizable'] !== FALSE) {
        drupal_add_js('misc/textarea.js');
        $class[] = 'resizable';
      }
    
      _form_set_class($element, $class);
      return theme('form_element', $element, '<textarea cols="'. $element['#cols'] .'" rows="'. $element['#rows'] .'" name="'. $element['#name'] .'" id="'. $element['#id'] .'" '. drupal_attributes($element['#attributes']) .'>'. check_plain($element['#value']) .'</textarea>');
    }
    
    /**
     * Format HTML markup for use in forms.
     *
     * This is used in more advanced forms, such as theme selection and filter format.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used: value, children.
     * @return
     *   A themed HTML string representing the HTML markup.
     *
     * @ingroup themeable
     */
    
    function theme_markup($element) {
      return (isset($element['#value']) ? $element['#value'] : '') . (isset($element['#children']) ? $element['#children'] : '');
    }
    
    /**
     * Format a password field.
     *
     * @param $element
     *   An associative array containing the properties of the element.
     *   Properties used:  title, value, description, size, maxlength, required, attributes
     * @return
     *   A themed HTML string representing the form.
     *
     * @ingroup themeable
     */
    function theme_password($element) {
      $size = $element['#size'] ? ' size="'. $element['#size'] .'" ' : '';
      $maxlength = $element['#maxlength'] ? ' maxlength="'. $element['#maxlength'] .'" ' : '';
    
      _form_set_class($element, array('form-text'));
      $output = '<input type="password" name="'. $element['#name'] .'" id="'. $element['#id'] .'" '. $maxlength . $size . drupal_attributes($element['#attributes']) .' />';
      return theme('form_element', $element, $output);
    }
    
    /**
     * Expand weight elements into selects.
     */
    function process_weight($element) {
      for ($n = (-1 * $element['#delta']); $n <= $element['#delta']; $n++) {
        $weights[$n] = $n;
      }
      $element['#options'] = $weights;
      $element['#type'] = 'select';
      $element['#is_weight'] = TRUE;
      $element += _element_info('select');
      return $element;
    }
    
    /**
     * Format a file upload field.
     *
     * @param $title
     *   The label for the file upload field.
     * @param $name
     *   The internal name used to refer to the field.
     * @param $size
     *   A measure of the visible size of the field (passed directly to HTML).
     * @param $description
     *   Explanatory text to display after the form item.
     * @param $required
     *   Whether the user must upload a file to the field.
     * @return
     *   A themed HTML string representing the field.
     *
     * @ingroup themeable
     *
     * For assistance with handling the uploaded file correctly, see the API
     * provided by file.inc.
     */
    function theme_file($element) {
      _form_set_class($element, array('form-file'));
      return theme('form_element', $element, '<input type="file" name="'. $element['#name'] .'"'. ($element['#attributes'] ? ' '. drupal_attributes($element['#attributes']) : '') .' id="'. $element['#id'] .'" size="'. $element['#size'] ."\" />\n");
    }
    
    /**
     * Return a themed form element.
     *
     * @param element
     *   An associative array containing the properties of the element.
     *   Properties used: title, description, id, required
     * @param $value
     *   The form element's data.
     * @return
     *   A string representing the form element.
     *
     * @ingroup themeable
     */
    function theme_form_element($element, $value) {
      // This is also used in the installer, pre-database setup.
      $t = get_t();
    
      $output  = '<div class="form-item"';
      if (!empty($element['#id'])) {
        $output .= ' id="'. $element['#id'] .'-wrapper"';
      }
      $output .= ">\n";
      $required = !empty($element['#required']) ? '<span class="form-required" title="'. $t('This field is required.') .'">*</span>' : '';
    
      if (!empty($element['#title'])) {
        $title = $element['#title'];
        if (!empty($element['#id'])) {
          $output .= ' <label for="'. $element['#id'] .'">'. $t('!title: !required', array('!title' => filter_xss_admin($title), '!required' => $required)) ."</label>\n";
        }
        else {
          $output .= ' <label>'. $t('!title: !required', array('!title' => filter_xss_admin($title), '!required' => $required)) ."</label>\n";
        }
      }
    
      $output .= " $value\n";
    
      if (!empty($element['#description'])) {
        $output .= ' <div class="description">'. $element['#description'] ."</div>\n";
      }
    
      $output .= "</div>\n";
    
      return $output;
    }
    
    /**
     * Sets a form element's class attribute.
     *
     * Adds 'required' and 'error' classes as needed.
     *
     * @param &$element
     *   The form element.
     * @param $name
     *   Array of new class names to be added.
     */
    function _form_set_class(&$element, $class = array()) {
      if ($element['#required']) {
        $class[] = 'required';
      }
      if (form_get_error($element)) {
        $class[] = 'error';
      }
      if (isset($element['#attributes']['class'])) {
        $class[] = $element['#attributes']['class'];
      }
      $element['#attributes']['class'] = implode(' ', $class);
    }
    
    /**
     * Prepare an HTML ID attribute string for a form item.
     *
     * Remove invalid characters and guarantee uniqueness.
     *
     * @param $id
     *   The ID to clean.
     * @param $flush
     *   If set to TRUE, the function will flush and reset the static array
     *   which is built to test the uniqueness of element IDs. This is only
     *   used if a form has completed the validation process. This parameter
     *   should never be set to TRUE if this function is being called to
     *   assign an ID to the #ID element.
     * @return
     *   The cleaned ID.
     */
    function form_clean_id($id = NULL, $flush = FALSE) {
      static $seen_ids = array();
    
      if ($flush) {
        $seen_ids = array();
        return;
      }
      $id = str_replace(array('][', '_', ' '), '-', $id);
    
      // Ensure IDs are unique. The first occurrence is held but left alone.
      // Subsequent occurrences get a number appended to them. This incrementing
      // will almost certainly break code that relies on explicit HTML IDs in
      // forms that appear more than once on the page, but the alternative is
      // outputting duplicate IDs, which would break JS code and XHTML
      // validity anyways. For now, it's an acceptable stopgap solution.
      if (isset($seen_ids[$id])) {
        $id = $id .'-'. $seen_ids[$id]++;
      }
      else {
        $seen_ids[$id] = 1;
      }
    
      return $id;
    }
    
    /**
     * @} End of "defgroup form".
     */
    
    /**
     * @defgroup batch Batch operations
     * @{
     * Functions allowing forms processing to be spread out over several page
     * requests, thus ensuring that the processing does not get interrupted
     * because of a PHP timeout, while allowing the user to receive feedback
     * on the progress of the ongoing operations.
     *
     * The API is primarily designed to integrate nicely with the Form API
     * workflow, but can also be used by non-FAPI scripts (like update.php)
     * or even simple page callbacks (which should probably be used sparingly).
     *
     * Example:
     * @code
     * $batch = array(
     *   'title' => t('Exporting'),
     *   'operations' => array(
     *     array('my_function_1', array($account->uid, 'story')),
     *     array('my_function_2', array()),
     *   ),
     *   'finished' => 'my_finished_callback',
     * );
     * batch_set($batch);
     * // only needed if not inside a form _submit handler :
     * batch_process();
     * @endcode
     *
     * Sample batch operations:
     * @code
     * // Simple and artificial: load a node of a given type for a given user
     * function my_function_1($uid, $type, &$context) {
     *   // The $context array gathers batch context information about the execution (read),
     *   // as well as 'return values' for the current operation (write)
     *   // The following keys are provided :
     *   // 'results' (read / write): The array of results gathered so far by
     *   //   the batch processing, for the current operation to append its own.
     *   // 'message' (write): A text message displayed in the progress page.
     *   // The following keys allow for multi-step operations :
     *   // 'sandbox' (read / write): An array that can be freely used to
     *   //   store persistent data between iterations. It is recommended to
     *   //   use this instead of $_SESSION, which is unsafe if the user
     *   //   continues browsing in a separate window while the batch is processing.
     *   // 'finished' (write): A float number between 0 and 1 informing
     *   //   the processing engine of the completion level for the operation.
     *   //   1 (or no value explicitly set) means the operation is finished
     *   //   and the batch processing can continue to the next operation.
     *
     *   $node = node_load(array('uid' => $uid, 'type' => $type));
     *   $context['results'][] = $node->nid .' : '. $node->title;
     *   $context['message'] = $node->title;
     * }
     *
     * // More advanced example: multi-step operation - load all nodes, five by five
     * function my_function_2(&$context) {
     *   if (empty($context['sandbox'])) {
     *     $context['sandbox']['progress'] = 0;
     *     $context['sandbox']['current_node'] = 0;
     *     $context['sandbox']['max'] = db_result(db_query('SELECT COUNT(DISTINCT nid) FROM {node}'));
     *   }
     *   $limit = 5;
     *   $result = db_query_range("SELECT nid FROM {node} WHERE nid > %d ORDER BY nid ASC", $context['sandbox']['current_node'], 0, $limit);
     *   while ($row = db_fetch_array($result)) {
     *     $node = node_load($row['nid'], NULL, TRUE);
     *     $context['results'][] = $node->nid .' : '. $node->title;
     *     $context['sandbox']['progress']++;
     *     $context['sandbox']['current_node'] = $node->nid;
     *     $context['message'] = $node->title;
     *   }
     *   if ($context['sandbox']['progress'] != $context['sandbox']['max']) {
     *     $context['finished'] = $context['sandbox']['progress'] / $context['sandbox']['max'];
     *   }
     * }
     * @endcode
     *
     * Sample 'finished' callback:
     * @code
     * function batch_test_finished($success, $results, $operations) {
     *   if ($success) {
     *     $message = format_plural(count($results), 'One post processed.', '@count posts processed.');
     *   }
     *   else {
     *     $message = t('Finished with an error.');
     *   }
     *   drupal_set_message($message);
     *   // Providing data for the redirected page is done through $_SESSION.
     *   foreach ($results as $result) {
     *     $items[] = t('Loaded node %title.', array('%title' => $result));
     *   }
     *   $_SESSION['my_batch_results'] = $items;
     * }
     * @endcode
     */
    
    /**
     * Open a new batch.
     *
     * @param $batch
     *   An array defining the batch. The following keys can be used:
     *     'operations': an array of function calls to be performed.
     *        Example:
     *        @code
     *        array(
     *          array('my_function_1', array($arg1)),
     *          array('my_function_2', array($arg2_1, $arg2_2)),
     *        )
     *        @endcode
     *     All the other values below are optional.
     *     batch_init() provides default values for the messages.
     *     'title': title for the progress page.
     *       Defaults to t('Processing').
     *     'init_message': message displayed while the processing is initialized.
     *       Defaults to t('Initializing.').
     *     'progress_message': message displayed while processing the batch.
     *       Available placeholders are @current, @remaining, @total and @percent.
     *       Defaults to t('Remaining @remaining of @total.').
     *     'error_message': message displayed if an error occurred while processing
     *       the batch.
     *       Defaults to t('An error has occurred.').
     *     'finished': the name of a function to be executed after the batch has
     *       completed. This should be used to perform any result massaging that
     *       may be needed, and possibly save data in $_SESSION for display after
     *       final page redirection.
     *     'file': the path to the file containing the definitions of the
     *       'operations' and 'finished' functions, for instance if they don't
     *       reside in the original '.module' file. The path should be relative to
     *       the base_path(), and thus should be built using drupal_get_path().
     *
     * Operations are added as new batch sets. Batch sets are used to ensure
     * clean code independence, ensuring that several batches submitted by
     * different parts of the code (core / contrib modules) can be processed
     * correctly while not interfering or having to cope with each other. Each
     * batch set gets to specify his own UI messages, operates on its own set
     * of operations and results, and triggers its own 'finished' callback.
     * Batch sets are processed sequentially, with the progress bar starting
     * fresh for every new set.
     */
    function batch_set($batch_definition) {
      if ($batch_definition) {
        $batch =& batch_get();
        // Initialize the batch
        if (empty($batch)) {
          $batch = array(
            'sets' => array(),
          );
        }
    
        $init = array(
          'sandbox' => array(),
          'results' => array(),
          'success' => FALSE,
        );
        // Use get_t() to allow batches at install time.
        $t = get_t();
        $defaults = array(
          'title' => $t('Processing'),
          'init_message' => $t('Initializing.'),
          'progress_message' => $t('Remaining @remaining of @total.'),
          'error_message' => $t('An error has occurred.'),
        );
        $batch_set = $init + $batch_definition + $defaults;
    
        // Tweak init_message to avoid the bottom of the page flickering down after init phase.
        $batch_set['init_message'] .= '<br/>&nbsp;';
        $batch_set['total'] = count($batch_set['operations']);
    
        // If the batch is being processed (meaning we are executing a stored submit handler),
        // insert the new set after the current one.
        if (isset($batch['current_set'])) {
          // array_insert does not exist...
          $slice1 = array_slice($batch['sets'], 0, $batch['current_set'] + 1);
          $slice2 = array_slice($batch['sets'], $batch['current_set'] + 1);
          $batch['sets'] = array_merge($slice1, array($batch_set), $slice2);
        }
        else {
          $batch['sets'][] = $batch_set;
        }
      }
    }
    
    /**
     * Process the batch.
     *
     * Unless the batch has been marked with 'progressive' = FALSE, the function
     * issues a drupal_goto and thus ends page execution.
     *
     * This function is not needed in form submit handlers; Form API takes care
     * of batches that were set during form submission.
     *
     * @param $redirect
     *   (optional) Path to redirect to when the batch has finished processing.
     * @param $url
     *   (optional - should only be used for separate scripts like update.php)
     *   URL of the batch processing page.
     */
    function batch_process($redirect = NULL, $url = NULL) {
      $batch =& batch_get();
    
      if (isset($batch)) {
        // Add process information
        $url = isset($url) ? $url : 'batch';
        $process_info = array(
          'current_set' => 0,
          'progressive' => TRUE,
          'url' => isset($url) ? $url : 'batch',
          'source_page' => $_GET['q'],
          'redirect' => $redirect,
        );
        $batch += $process_info;
    
        if ($batch['progressive']) {
          // Clear the way for the drupal_goto redirection to the batch processing
          // page, by saving and unsetting the 'destination' if any, on both places
          // drupal_goto looks for it.
          if (isset($_REQUEST['destination'])) {
            $batch['destination'] = $_REQUEST['destination'];
            unset($_REQUEST['destination']);
          }
          elseif (isset($_REQUEST['edit']['destination'])) {
            $batch['destination'] = $_REQUEST['edit']['destination'];
            unset($_REQUEST['edit']['destination']);
          }
    
          // Initiate db storage in order to get a batch id. We have to provide
          // at least an empty string for the (not null) 'token' column.
          db_query("INSERT INTO {batch} (token, timestamp) VALUES ('', %d)", time());
          $batch['id'] = db_last_insert_id('batch', 'bid');
    
          // Now that we have a batch id, we can generate the redirection link in
          // the generic error message.
          $t = get_t();
          $batch['error_message'] = $t('Please continue to <a href="@error_url">the error page</a>', array('@error_url' => url($url, array('query' => array('id' => $batch['id'], 'op' => 'finished')))));
    
          // Actually store the batch data and the token generated form the batch id.
          db_query("UPDATE {batch} SET token = '%s', batch = '%s' WHERE bid = %d", drupal_get_token($batch['id']), serialize($batch), $batch['id']);
    
          drupal_goto($batch['url'], 'op=start&id='. $batch['id']);
        }
        else {
          // Non-progressive execution: bypass the whole progressbar workflow
          // and execute the batch in one pass.
          require_once './includes/batch.inc';
          _batch_process();
        }
      }
    }
    
    /**
     * Retrieve the current batch.
     */
    function &batch_get() {
      static $batch = array();
      return $batch;
    }
    
    /**
     * @} End of "defgroup batch".
     */