modules/simplelist/simplelist.module

<?php
// $Id$

require_once(drupal_get_path('module', 'simplelist') .'/SimpleListController.php');
  
define('SIMPLELIST_UNPUBLISHED_NODES', 0);
define('SIMPLELIST_PUBLISHED_NODES', 1);
define('SIMPLELIST_ALL_NODES', 2);

define('SIMPLELIST_FORMAT_TEASER', 0);
define('SIMPLELIST_FORMAT_FULL', 1);
define('SIMPLELIST_FORMAT_THEME', 2);
define('SIMPLELIST_FORMAT_TITLE_LINK', 3);

/**
 * Implements hook_block.
 *
 * @param unknown_type $op
 * @param unknown_type $delta
 * @param unknown_type $edit
 * @return unknown
 */
function simplelist_block($op = 'list', $delta = 0, $edit = array()) {
  if ($op == 'list') {
    $items = array();
    $query = "SELECT sl.slid, sl.name, sl.cache, sld.display_title FROM {simplelist} sl INNER JOIN {simplelist_display} sld ON (sl.slid = sld.slid AND sld.display_context = '%s')";
    $result = db_query($query, "block");
    while ($simple_list = db_fetch_object($result)) {
      $items[$simple_list->name] = array('info' => ($simple_list->display_title?$simple_list->display_title:$simple_list->name), 'cache' => $simple_list->cache);
    }
    return $items;
  }
  else if ($op == 'view') {
    $sl_controller = new SimpleListController($delta, 'block');
    return $sl_controller->getRenderedList();
  }
}

/**
 * Implements hook_help().
 *
 * @param unknown_type $path
 * @param unknown_type $arg
 */
function simplelist_help($path, $arg) {
  switch ($path) {
    case 'admin/build/simplelist':
      return '<p>'. t('Simplelists are lists of nodes (or other items in the future).  From this page you can edit, clone, or delete any existing simplelists, or add a new one.') .'</p>';
    case 'admin/build/simplelist/add':
      return '<p>'. t('Set a name for your list, choose a Filter and block display and/or page display options.  A filter is the method you want to use to choose what nodes to display in the list.  If you choose a block, you\'ll need to set how the nodes will display in the block.  If you choose a page, you\'ll need to set how the nodes will display, and the path to display on. If you choose to use a theme function to display your nodes, the theme is named "simplelist__<name of simplelist>" - note that is two underscores.') .'</p>';
  }
}

/**
 * Implements hook_perm().
 *
 * @return unknown
 */
function simplelist_perm() {
  return array('administer simplelist');
}

/**
 * Implements hook_menu().
 *
 * @return array
 */
function simplelist_menu() {
  $item = array();

  $item['simplelist/filter/ahah'] = array(
    'page callback' => '_simplelist_filter_ahah',
    'access arguments' => array('administer simplelist'),
    'type' => MENU_CALLBACK,
  );
  $item['simplelist/display/ahah'] = array(
    'page callback' => '_simplelist_display_ahah',
    'access arguments' => array('administer simplelist'),
    'type' => MENU_CALLBACK,
  );
  $item['admin/build/simplelist'] = array(
    'title' => 'SimpleList',
    'page callback' => '_simplelist_admin_page',
    'access arguments' => array('administer simplelist'),
    'description' => 'Simplelist makes it easy to present nodes in list form without much/any coding.',
    'type' => MENU_NORMAL_ITEM,
  );
  $item['admin/build/simplelist/list'] = array(
    'title' => 'List',
    'page callback' => '_simplelist_admin_page',
    'access arguments' => array('administer simplelist'),
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => '-1',
  );
  $item['admin/build/simplelist/add'] = array(
    'title' => 'Add',
    'page callback' => '_simplelist_admin_add_page',
    'access arguments' => array('administer simplelist'),
    'type' => MENU_LOCAL_TASK,
  );
  $item['admin/build/simplelist/delete/%'] = array(
    'title' => 'Delete',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('_simplelist_admin_delete_confirm', 4),
    'access arguments' => array('administer simplelist'),
    'type' => MENU_CALLBACK,
  );
  $item['admin/build/simplelist/%simplelist/edit'] = array(
    'title' => 'Edit',
    'page callback' => '_simplelist_admin_edit_page',
    'page arguments' => array(3),
    'access arguments' => array('administer simplelist'),
    'weight' => -5,
    'type' => MENU_CALLBACK,
  );
  $item['admin/build/simplelist/%simplelist/clone'] = array(
    'title' => 'Clone',
    'page callback' => '_simplelist_admin_clone_page',
    'page arguments' => array(3),
    'access arguments' => array('administer simplelist'),
    'type' => MENU_CALLBACK,
  );
  
  // This section pulls out the simplelist pages to add to the menu.
  $query = "SELECT slid, display_title, display_path FROM {simplelist_display} WHERE display_context = 'page'";
  $result = db_query($query);
  
  while ($row = db_fetch_object($result)) {
    $count = 0;
    $args = array($row->slid);
    $path = $row->display_path;
    if ($wild_pos = strpos($path, '%tid')) {
      $arg_pos = substr_count($path, '/', 0, $wild_pos);
      $path = str_replace('%tid', '%', $path, $count);
      $args[] = 'tid';
      $args[] = $arg_pos;
    }
    if ($wild_pos = strpos($path, '%node_type')) {
      $arg_pos = substr_count($path, '/', 0, $wild_pos);
      $path = str_replace('%node_type', '%simplelist_node_type', $path, $count);
      $args[] = 'node_type';
      $args[] = $arg_pos;
    }
    
    $item[$path] = array(
      'title' => $row->display_title,
      'page callback' => '_simplelist_path_display',
      'page arguments' => $args, 
      'access callback' => '_simplelist_menu_access',
      'access arguments' => array($row->slid),
      'type' => MENU_CALLBACK,
    ); 
  }
  
  return $item;
}

/**
 * Wrapper function that is used by menu wildcards to load a simplelist for editing.
 *
 * @param int $slid
 * @return simplelist
 */
function simplelist_load($slid) {
  return SimpleListController::load_simple_list($slid, 'all');
}

/**
 * Wrapper function that is used by menu wildcards to load a path.
 */
function simplelist_node_type_load($node_type) {
  return node_get_types('type', $node_type);
}

/**
 * A wrapper function to help a menu entry to easily check access rights.
 *
 * @param unknown_type $slid
 * @return unknown
 */
function _simplelist_menu_access($slid) {
  $access_rights = db_result(db_query("SELECT access FROM {simplelist} WHERE slid = %d", $slid));
  
  if ($access_rights) {
    global $user;
    return SimpleListController::checkSimpleListAccess(unserialize($access_rights), $user->roles);
  }
  return TRUE;
}

/**
 * Implements hook_theme, so that folks can define how to theme their blocks.
 *
 * @return array
 *   Theme function information
 */
function simplelist_theme() {
  return array(
    'simplelist' => array(
      'arguments' => array('node' => NULL, 'simplelist' => NULL),
      'pattern' => 'simplelist__',
    ),
    'simplelist__simplelist_test_theme_list' => array(
      'arguments' => array('node' => NULL, 'simplelist' => NULL),
    ),
  );
}

/**
 * Base default theme of a node, if the developer hasn't defined theme_simplelist__$simplelist->name.
 *
 * @param unknown_type $node
 * @param unknown_type $simplelist
 * @return unknown
 */
function theme_simplelist($node, $simplelist) {
  return check_plain($node->title);
}

/**
 * This is a test theme, just done to make sure the proper overrides work.
 *
 * @param unknown_type $node
 * @param unknown_type $simplelist
 * @return unknown
 */
function theme_simplelist__simplelist_test_theme_list($node, $simplelist) {
  return 'I love '. check_plain($node->title);
}

/**
 * This function handles the page-based simplelists - first it tries to set up any path arguments, then renders the page.
 * 
 * The arguments may or may not be there, but will be set up in the dynamically set hook_menu items.  The Controller knows what to do with them...
 *
 * @param unknown_type $slid
 * @param unknown_type $type1
 * @param unknown_type $id1
 * @param unknown_type $type2
 * @param unknown_type $id2
 * @return unknown
 */
function _simplelist_path_display($slid, $type1 = '', $id1 = -1, $type2 = '', $id2 = -1) {
  $controller = new SimpleListController($slid, 'page');
  if ($type1 != '') {
    $controller->setArgument($type1, $id1);
    if ($type2 != '') {
      $controller->setArgument($type2, $id2);
    }
  }
  
  return $controller->getRenderedList();
}

/**
 * Implements hook_simplelist_filter_list().
 *
 * @return unknown
 */
function simplelist_simplelist_filter_info() {
  return array(
    array('name' => 'SimpleListNodeFilter', 'title' => t('Simple Node Filter'), 'provides' => 'node'),
    array('name' => 'SimpleListFilterNodeByUser', 'title' => t('Filter Node By User'), 'provides' => 'node'),
  );
}

/**
 * Implements hook_simplelist_filter_require().
 *
 */
function simplelist_simplelist_filter_require() {
  require_once(drupal_get_path('module', 'simplelist') .'/SimpleListNodeFilter.php');
  require_once(drupal_get_path('module', 'simplelist') .'/SimpleListFilterNodeByUser.php');
}

/**
 * Implements hook_simplelist_display_info().
 *
 * @param unknown_type $op
 * @return unknown
 */
function simplelist_simplelist_display_info($op = 'list') {
  return array(
    array('name' => 'SimpleListDisplay', 'title' => t('Display as List'), 'accepts' => 'node'),
    array('name' => 'SimpleListDisplayCascade', 'title' => t('Display as series of items'), 'accepts' => 'node'),
  );
}

/**
 * Implements hook_simplelist_display_require().
 *
 */
function simplelist_simplelist_display_require() {
  require_once(drupal_get_path('module', 'simplelist') .'/SimpleListDisplay.php');
  require_once(drupal_get_path('module', 'simplelist') .'/SimpleListDisplayCascade.php');
}

/**
 * Requires/includes all of the filter classes that simplelist knows of.
 *
 */
function simplelist_require_all_filter_classes() {
  module_invoke_all('simplelist_filter_require');
}

/**
 * Requires/includes all of the display classes that simplelist knows of.
 *
 */
function simplelist_require_all_display_classes() {
  module_invoke_all('simplelist_display_require');
}

/**
 * Returns the list of filter classes available to list from.
 *
 * @return unknown
 */
function _simplelist_get_filter_options() {
  $filter_array = array();
  
  $modules = module_implements('simplelist_filter_info');
  foreach ($modules as $module) {
    $items = module_invoke($module, 'simplelist_filter_info');
    foreach ($items as $detail) {
      $filter_array[$detail['name']] = $detail['title'];
    }
  }
  
  return $filter_array;
}

/**
 * Given a filter name, we fetch the type of objects that filter provides.
 *
 * @param unknown_type $filter_name
 * @return unknown
 */
function _simplelist_get_filter_provides($filter_name) {
  static $filter_provides = array();
  if (!count($filter_provides)) {
    $modules = module_implements('simplelist_filter_info');
    foreach ($modules as $module) {
      $items = module_invoke($module, 'simplelist_filter_info');
      foreach ($items as $detail) {
        $filter_provides[$detail['name']] = $detail['provides'];
      }
    }
  }
  
  if (isset($filter_provides[$filter_name])) {
    return $filter_provides[$filter_name];
  }
  return NULL;
}

/**
 * Returns the list of display classes available to list from.
 *
 * Placeholder as well.
 * 
 * @return unknown
 */
function _simplelist_get_display_options($type = 'all') {
  $display_array = array();
  
  $modules = module_implements('simplelist_display_info');
  foreach ($modules as $module) {
    $items = module_invoke($module, 'simplelist_display_info');
    foreach ($items as $detail) {
      if ($type == 'all' || $type == $detail['accepts']) {
        $display_array[$detail['name']] = $detail['title'];
      }
    }
  }
  
  return $display_array;
}

/*
 * ADMIN SECTION STARTS HERE
 */

/**
 * Page callback that displays a list of simplelists that have been defined.
 *
 */
function _simplelist_admin_page() {
  $num_rows = 25;

  drupal_set_title(t('Administer Simplelists'));

  $result = pager_query("SELECT sl.slid, name, description, display_context FROM {simplelist} sl INNER JOIN {simplelist_display} sld ON (sl.slid = sld.slid) ORDER BY sl.name", $num_rows);

  $table_items = array();
  while ($row = db_fetch_object($result)) {
    $size = count($table_items) - 1;
    if (size >= 0 && $row->name == $table_items[$size][0]) {
      $table_items[$size][2] .= ', '. $row->display_context;
    }
    else {
      $table_items[] = array(
        $row->name,
        $row->description,
        $row->display_context,
        theme('links', array(
          array('title' => t('Edit'), 'href' => "admin/build/simplelist/$row->slid/edit"),
          array('title' => t('Delete'), 'href' => "admin/build/simplelist/delete/$row->slid"),
          array('title' => t('Clone'), 'href' => "admin/build/simplelist/$row->slid/clone"),
        ))
      );
    }
  }

  if ($table_items) {
    $output = theme('table', array(t('Name'), t('Description'), t('Contexts'), t('Actions')), $table_items, array("cellpadding" => "4"), t('Existing Simplelists'));
    $output .= theme('pager', NULL, $num_rows);
  }
  else {
    $output .= t('<p>No Simplelists have currently been defined.</p>');
  }

  return $output;
}

/**
 * Wrapper function callback to display the edit form when user wants to add a simplelist.
 *
 * @return unknown
 */
function _simplelist_admin_add_page() {
  $simplelist = SimpleListController::getDefault();

  drupal_set_title(t('Add a Simplelist'));

  return drupal_get_form('_simplelist_edit_form', $simplelist, 'add');
}

/**
 * Wrapper function callback to display the edit form (filled) when user wants to add a simplelist.
 *
 * @param unknown_type $simplelist
 * @return unknown
 */
function _simplelist_admin_edit_page($simplelist = NULL) {

  drupal_set_title(t('Edit a Simplelist'));

  return drupal_get_form('_simplelist_edit_form', $simplelist);
}

/**
 * Displays the simplelist edit page, with the fields pre-filled to clone the given simplelist.
 *
 * @param unknown_type $simplelist
 * @return unknown
 */
function _simplelist_admin_clone_page($simplelist = NULL) {
  
  drupal_set_title(t('Clone a Simplelist'));
  
  $simplelist->slid = 0;
  $simplelist->displays['block']->sldid = 0;
  $simplelist->displays['page']->sldid = 0;
  
  return drupal_get_form('_simplelist_edit_form', $simplelist);
}

/**
 * Displays the confirm form to make sure the user really wants to delete a simplelist.
 *
 * @param unknown_type $form_state
 * @param unknown_type $slid
 * @return unknown
 */
function _simplelist_admin_delete_confirm(&$form_state, $slid = '') {
  $simplelist = simplelist_load($slid);

  if (!$simplelist) {
    return drupal_goto('admin/build/simplelist');
  }

  $form['slid'] = array('#type' => 'value', '#value' => $simplelist->slid);

  $form = confirm_form($form,
    t('Are you sure you want to delete %title?', array('%title' => $nc->name)),
    $_GET['destination'] ? $_GET['destination'] : 'admin/build/simplelist',
    t('This action cannot be undone.'),
    t('Delete'), t('Cancel')
  );
  return $form;
}

/**
 * Handle the submit button to delete a nodecarousel.
 *
 * @param string $form_id
 *   Standard form_id for submit functions in formapi.
 * @param array $form_state
 *   Array of form values for deletion.
 */
function _simplelist_admin_delete_confirm_submit($form, &$form_state) {
  _simplelist_delete((object) $form_state['values']);
  $form_state['redirect'] = 'admin/build/simplelist';
}

/**
 * Deletes a given simplelist.
 *
 * @param unknown_type $form_values
 */
function _simplelist_delete($form_values) {
  $form_values->slid = intval($form_values->slid);

  if (!$form_values->slid) {
    return;
  }

  db_query("DELETE FROM {simplelist_display} WHERE slid = %d", $form_values->slid);
  db_query("DELETE FROM {simplelist_terms} WHERE slid = %d", $form_values->slid);
  db_query("DELETE FROM {simplelist_types} WHERE slid = %d", $form_values->slid);
  db_query("DELETE FROM {simplelist} WHERE slid = %d", $form_values->slid);
}

/**
 * Rebuilds form for AHAH display call, and returns to the page the new fields.
 * 
 * This is liberally poached from the Poll module.  The tricky part of passing back form elements in AHAH is that the 
 * Form API checks with form_cache to make sure that the data it's sent matches with the form it's supposed to have.
 *
 * @param unknown_type $type
 */
function _simplelist_display_ahah($type = 'block') {
  simplelist_require_all_display_classes();
  if ($type == 'block') {
    $class_name = $_POST['block_display_name'];
    $form_area = 'block_display'; 
  }
  else {
    $class_name = $_POST['page_display_name'];
    $form_area = 'page_display';
  }
  _simplelist_common_ahah($type, $class_name, 'get_display_form', $form_area);
}

/**
 * Rebuilds form for AHAH filter call, and returns to the page the new fields.
 * 
 * This is liberally poached from the Poll module.  The tricky part of passing back form elements in AHAH is that the 
 * Form API checks with form_cache to make sure that the data it's sent matches with the form it's supposed to have.
 *
 */
function _simplelist_filter_ahah() {
  simplelist_require_all_filter_classes();
  $class_name = $_POST['filter_name'];
  _simplelist_common_ahah('filter', $class_name, 'get_filter_form', 'SimpleListNodeFilter');
}

/**
 * The common ahah form handling functionality.  
 *
 * @param unknown_type $type
 *   The type of form elements - 'filter', 'block', or 'page'.
 * @param unknown_type $class_name 
 *   The name of the class providing the new form elements
 * @param unknown_type $function_name
 *   The name of the function to get the form elements from on $class_name
 * @param unknown_type $form_area
 *   The sub-section of the form which we're changing.
 */
function _simplelist_common_ahah($type, $class_name, $function_name, $form_area) {
  
  // Get the form out of the cache.
  $form_state = array('submitted' => FALSE);
  $form_build_id = $_POST['form_build_id'];
  $form = form_get_cache($form_build_id, $form_state);
  
  // Get the new form elements from the display class.
  if ($form['slid']['#value'] == 0) {
    $simplelist = SimpleListController::getDefault();
  }
  else {
    $simplelist = simplelist_load($form['slid']['#value']);
  }
  $form_elements = call_user_func(array($class_name, $function_name), $simplelist, $type);
  
  if ($type == 'filter') {
    $form_section = $form;
  }
  else {
    $form_section = $form['display'];
  }
  // Remove the unwanted elements from the form, add in the new elements in $form_elements, and then put the form back in the cache.
  foreach ($form_section[$type][$form_area] as $key => $item) {
    unset($form_section[$type][$form_area][$key]);
  }
  $require_js = array();
  foreach ($form_elements as $delta => $item) {
    $form_section[$type][$form_area][$delta] = $item;
  }
  if ($type == 'filter') {
    $form = $form_section;
  }
  else {
    $form['display'] = $form_section;
  }

  form_set_cache($form_build_id, $form, $form_state);
  $form += array(
    '#post' => $_POST,
    '#programmed' => FALSE,
  );
  
  // Rebuild the form.
  $form = form_builder('_simplelist_edit_form', $form, $form_state);
  
  // Render the new output.
  if ($type == 'filter') {
    $choice_form = $form[$type][$form_area];
  }
  else {
    $choice_form = $form['display'][$type][$form_area];
  }
  unset($choice_form['#prefix'], $choice_form['#suffix']); // Prevent duplicate wrappers.

  $output = theme('status_messages') . drupal_render($choice_form);
  
  drupal_json(array('status' => TRUE, 'data' => $output));
}

/**
 * Basic edit form - displays form for user to add/edit a simplelist.
 * 
 * Note that filter and display-specific simplelist elements are handled by their class in the get_filter_form_submit 
 *   or get_display_form_submit methods.
 *
 * @param unknown_type $form_state
 * @param unknown_type $simplelist
 * @param unknown_type $op
 * @return unknown
 */
function _simplelist_edit_form(&$form_state, $simplelist, $op = '') {
  simplelist_require_all_filter_classes();
  simplelist_require_all_display_classes();
  drupal_add_js('misc/autocomplete.js'); // Because if we need it it's better to have it now than mess with it in the AHAH.
  $form = array();

  $form['slid'] = array('#type' => 'value', '#value' => $simplelist->slid);
  $form['simplelist'] = array('#type' => 'value', '#value' => $simplelist);

  $form['basic-info'] = array(
    '#type' => 'fieldset',
    '#collapsible' => true,
    '#collapsed' => false,
    '#title' => t('Basic Information'),
  );

  $form['basic-info']['name'] = array(
    '#type' => 'textfield',
    '#title' => t('Name'),
    '#default_value' => $simplelist->name,
    '#size' => 20,
    '#maxlength' => 32,
    '#description' => t('The unique identifier of the simplelist. Only alphanumeric and _ allowed here'),
    '#required' => true,
  );

  $form['basic-info']['access'] = array(
    '#type' => 'checkboxes',
    '#title' => t('Access'),
    '#default_value' => $simplelist->access,
    '#options' => user_roles(),
    '#description' => t('Only the checked roles will be able to see this simplelist block or page in any form; if no roles are checked, access will not be restricted.'),
  );

  $form['basic-info']['description'] = array(
    '#type' => 'textfield',
    '#title' => t('Description'),
    '#default_value' => $simplelist->description,
    '#size' => 60,
    '#maxlength' => 255,
    '#description' => t('A description of the simplelist for the admin list.'),
  );
  
  $form['basic-info']['cache'] = array(
    '#type' => 'select',
    '#title' => 'Block Caching',
    '#default_value' => $simplelist->cache,
    '#options' => array(
       BLOCK_NO_CACHE => t('No Caching'),
       BLOCK_CACHE_PER_ROLE => t('Cache by role'),
       BLOCK_CACHE_PER_USER => t('Cache by user'),
       BLOCK_CACHE_PER_PAGE => t('Cache by page'),
       BLOCK_CACHE_GLOBAL => t('Cache Globally')),
    '#multiple' => FALSE,
    '#required' => TRUE,
    '#description' => t('How the block should be cached by drupal.'),
  );
  
  $form['basic-info']['published'] = array(
    '#type' => 'select',
    '#title' => 'Show Published Nodes?',
    '#default_value' => $simplelist->published,
    '#options' => array(
      SIMPLELIST_UNPUBLISHED_NODES => t('Show only unpublished nodes'),
      SIMPLELIST_PUBLISHED_NODES => t('Show only published nodes - Recommended'),
      SIMPLELIST_ALL_NODES => t('Show all nodes'),
    ),
    '#multiple' => FALSE,
    '#required' => TRUE,
    '#description' => t('Indicate if the list should filter nodes by their status.  It\'s recommended that you leave it at \'Show only published nodes\'.'),
  );

  $form['filter'] = array(
    '#type' => 'fieldset',
    '#collapsible' => true,
    '#collapsed' => false,
    '#title' => t('Filter Options'),
  );
  
  $form['filter']['help'] = array(
    '#value' => '<p>This section is where you indicate what sort of information you want to display, and the order to display it in.</p>',
    '#weight' => -10,
  );
  
  $form['filter']['filter_name'] = array(
    '#type' => 'select',
    '#title' => t('Filter'),
    '#default_value' => $simplelist->filter_name,
    '#options' => _simplelist_get_filter_options(),
    '#multiple' => FALSE,
    '#required' => TRUE,
    '#description' => t('What sort of a search for information you want.'),
    '#weight' => -9,
    '#ahah' => array(
      'path' => 'simplelist/filter/ahah',
      'wrapper' => 'filter-choices',
      'method' => 'replace',
      'effect' => 'fade',
    ),
  );
  
  // Container for just the filter choices.
  $form['filter']['SimpleListNodeFilter'] = array(
    '#prefix' => '<div id="filter-choices">',
    '#suffix' => '</div>',
    '#theme' => 'filter_choices',
  );
  
  $form_elements = call_user_func(array($simplelist->filter_name, 'get_filter_form'), $simplelist);

  foreach ($form_elements as $delta => $item) {
    $form['filter']['SimpleListNodeFilter'][$delta] = $item;
  }
  
  $form['display'] = array(
    '#type' => 'fieldset',
    '#collapsible' => true,
    '#collapsed' => false,
    '#title' => t('Display Options'),
  );
  
  $form['display']['block'] = array(
    '#type' => 'fieldset',
    '#collapsible' => TRUE,
    '#collapsed' => FALSE,
    '#title' => t('Block Display Options'),
  );
  
  $form['display']['block']['block_select'] = array(
    '#type' => 'checkbox',
    '#title' => 'Use Block?',
    '#default_value' => (!empty($simplelist->displays['block']) && $simplelist->displays['block']->display_name != ''),
    '#weight' => -9,
  );
  
  $block_display_options = _simplelist_get_display_options();
  $form['display']['block']['block_display_name'] = array(
    '#type' => 'select',
    '#title' => t('Display'),
    '#default_value' => $simplelist->displays['block']->display_name,
    '#options' => $block_display_options,
    '#multiple' => FALSE,
    '#required' => TRUE,
    '#description' => t('What sort of a block you want.'),
    '#weight' => -7,
    '#ahah' => array(
      'path' => 'simplelist/display/ahah/block',
      'wrapper' => 'block-display-choices',
      'method' => 'replace',
      'effect' => 'fade',
    ),
  );
  
  // Container for just the block display choices.
  $form['display']['block']['block_display'] = array(
    '#prefix' => '<div id="block-display-choices">',
    '#suffix' => '</div>',
    /*'#theme' => 'block_filter_choices',*/
  );
  
  $block_display_keys = array_keys($block_display_options);
  $block_display_name = isset($simplelist->displays['block']->display_name) ? $simplelist->displays['block']->display_name : $block_display_keys[0];
  $form_elements = call_user_func(array($block_display_name, 'get_display_form'), $simplelist, 'block');

  foreach ($form_elements as $delta => $item) {
    $form['display']['block']['block_display'][$delta] = $item;
  }
  
  $form['display']['page'] = array(
    '#type' => 'fieldset',
    '#collapsible' => TRUE,
    '#collapsed' => FALSE,
    '#title' => t('Page Display Options'),
  );
  
  $form['display']['page']['page_select'] = array(
    '#type' => 'checkbox',
    '#title' => 'Use Page?',
    '#default_value' => (!empty($simplelist->displays['page']) && $simplelist->displays['page']->display_name != ''),
    '#weight' => -9,
  );
  
  $page_display_options = _simplelist_get_display_options();
  $form['display']['page']['page_display_name'] = array(
    '#type' => 'select',
    '#title' => t('Display'),
    '#default_value' => $simplelist->displays['page']->display_name,
    '#options' => $page_display_options,
    '#multiple' => FALSE,
    '#required' => TRUE,
    '#description' => t('What sort of a page you want.'),
    '#weight' => -9,
    '#ahah' => array(
      'path' => 'simplelist/display/ahah/page',
      'wrapper' => 'page-display-choices',
      'method' => 'replace',
      'effect' => 'fade',
    ),
  );
  
  // Container for just the block display choices.
  $form['display']['page']['page_display'] = array(
    '#prefix' => '<div id="page-display-choices">',
    '#suffix' => '</div>',
    /*'#theme' => 'block_filter_choices',*/
  );
  
  $page_display_keys = array_keys($page_display_options);
  $page_display_name = isset($simplelist->displays['page']->display_name) ? $simplelist->displays['page']->display_name : $page_display_keys[0];
  
  $form_elements = call_user_func(array($page_display_name, 'get_display_form'), $simplelist, 'page');

  foreach ($form_elements as $delta => $item) {
    $form['display']['page']['page_display'][$delta] = $item;
  }

  $form['submit'] = array('#type' => 'submit', '#value' => t('Save'));

  return $form;
}

/**
 * Validates that a given value is a whole number between 1 and 999
 *
 * @param string $value
 *   The value to check
 * @return boolean
 *   True if the value is an integer between 1 and 999.
 */
function _simplelist_validate_numeric($value) {
  return (is_numeric($value) && $value > 0 && $value <= 999 && $value == (int)$value );
}

/**
 * Simplelist add/edit for validation.
 * 
 * Note that we also call the filters and displays to use their own form validates.
 *
 * @param unknown_type $form
 * @param unknown_type $form_state
 */
function _simplelist_edit_form_validate(&$form, &$form_state) {
  simplelist_require_all_filter_classes();
  simplelist_require_all_display_classes();
  
  // Validate the name is good.
  if (preg_match('![^a-z0-9_]!i', $form_state['values']['name'])) {
    form_set_error('name', t('Simplelist Names can only contain the letters a-z, numbers, and the underscore character.'));
  }
  else {
    // Assure that the name is unique.
    $count = db_result(db_query("SELECT COUNT(slid) FROM {simplelist} WHERE name = '%s' AND slid <> %d", $form_state['values']['name'], $form_state['values']['slid']));
    if ($count) {
      form_set_error('name', t('Simplelist names must be unique - please choose a different name, as this one is already in use.'));
    }
  }
  
  call_user_func(array($form_state['values']['filter_name'], 'get_filter_form_validate'), $form, $form_state);
  
  if ($form_state['values']['block_select']) {
    call_user_func(array($form_state['values']['block_display_name'], 'get_display_form_validate'), $form, $form_state, 'block');
  }
  
  if ($form_state['values']['page_select']) {
    call_user_func(array($form_state['values']['page_display_name'], 'get_display_form_validate'), $form, $form_state, 'page');
  }
  
  // Make sure that *one* of the display areas is enabled, for goodness sakes.
  if (! ($form_state['values']['block_select'] || $form_state['values']['page_select'])) {
    form_set_error('block_select', t('A simplelist requires either the <em>Use Block?</em> or <em>Use Page?</em> to be displayed.'));
  }
}

/**
 * Simplelist add/edit submit function
 *
 * @param unknown_type $form_id
 * @param unknown_type $form_state
 */
function _simplelist_edit_form_submit($form_id, &$form_state) {
  simplelist_require_all_filter_classes();
  simplelist_require_all_display_classes();

  
  if ($form_state['values']['slid'] == 0) { // Inserting new simplelist.
    _simplelist_insert($form_id, $form_state);
    if ($form_state['values']['slid'] != 0) {
      drupal_set_message('Simplelist '. $form_state['values']['name'] .' has been created');
    }
  }
  else {
    _simplelist_update($form_id, $form_state);
    drupal_set_message('Simplelist '. $form_state['values']['name'] .' has been updated');
  }
  
  
  $form_state['redirect'] = 'admin/build/simplelist';
}

/**
 * Prepare the access choices for writing to the db.
 *
 * @param unknown_type $form_state
 * @return unknown
 */
function _simplelist_prepare_access($form_state) {
  $access = array();
  foreach ($form_state['values']['access'] as $key => $value) {
    if ($value) {
      $access[] = $key;
    }
  }
  return $access;
}

/**
 * Writes the new simplelist into the database.
 *
 * @param unknown_type $form_id
 * @param unknown_type $form_state
 */
function _simplelist_insert($form_id, &$form_state) {
  $query = "INSERT INTO {simplelist} (name, description, access, filter_name, filter_data, sort_name, sort_data, cache, published) ". 
    "VALUES ('%s', '%s', '%s', '%s', '%s', '%s', '%s', %d, %d)";
  db_query($query, $form_state['values']['name'], $form_state['values']['description'], serialize(_simplelist_prepare_access($form_state)), $form_state['values']['filter_name'],
    $form_state['values']['filter_data'], $form_state['values']['sort_name'], $form_state['values']['sort_data'], 
    $form_state['values']['cache'], $form_state['values']['published']);
    
  $slid = db_last_insert_id('simplelist', 'slid');
  $form_state['values']['slid'] = $slid;
  call_user_func(array($form_state['values']['filter_name'], 'get_filter_form_submit'), $form_id, $form_state);
  
  if ($form_state['values']['block_select']) {
    call_user_func(array($form_state['values']['block_display_name'], 'get_display_form_submit'), $form_id, $form_state, 'block');
  }
  if ($form_state['values']['page_select']) {
    call_user_func(array($form_state['values']['page_display_name'], 'get_display_form_submit'), $form_id, $form_state, 'page');
    menu_rebuild();
  }
}

/**
 * Updates the simplelist into the database.
 *
 * @param unknown_type $form_id
 * @param unknown_type $form_state
 */
function _simplelist_update($form_id, &$form_state) {
  $slid = $form_state['values']['slid'];
  $old_simplelist = $form_state['values']['simplelist'];
  
  $query = "UPDATE {simplelist} SET name = '%s', description = '%s', access = '%s', filter_name = '%s', filter_data = '%s', ".
    "sort_name = '%s', sort_data = '%s', cache = %d, published = %d WHERE slid = %d";
  db_query($query, $form_state['values']['name'], $form_state['values']['description'], serialize(_simplelist_prepare_access($form_state)), $form_state['values']['filter_name'],
    $form_state['values']['filter_data'], $form_state['values']['sort_name'], $form_state['values']['sort_data'], 
    $form_state['values']['cache'], $form_state['values']['published'], $slid);

  // Are we changing filters?  If so, we need to clean up after the old one...
  if ($old_simplelist->filter_name != $form_state['values']['filter_name']) {
    call_user_func(array($old_simplelist->filter_name, 'clear_existing_settings'), $slid, $form_id, $form_state);
  }
  call_user_func(array($form_state['values']['filter_name'], 'get_filter_form_submit'), $form_id, $form_state);

  // Are we changing the block display?  If so, we'll need to clean up after the old one...
  if ($old_simplelist->displays['block']->display_name != '' && $old_simplelist->displays['block']->display_name != $form_state['values']['block_display_name']) {
    call_user_func(array($old_simplelist->displays['block']->display_name, 'clear_existing_settings'), $slid, $form_id, $form_state, 'block');
  }
  call_user_func(array($form_state['values']['block_display_name'], 'get_display_form_submit'), $form_id, $form_state, 'block');

  // And again, if we're changing the page display, we'll need to clean up after the old one...
  if ($old_simplelist->displays['page']->display_name != '' && $old_simplelist->displays['page']->display_name != $form_state['values']['page_display_name']) {
    call_user_func(array($old_simplelist->displays['page']->display_name, 'clear_existing_settings'), $slid, $form_id, $form_state, 'page');
  }
  $menu_rebuild = call_user_func(array($form_state['values']['page_display_name'], 'get_display_form_submit'), $form_id, $form_state, 'page');

  if ($menu_rebuild) {
    menu_rebuild();
  }
}