<?php
// $Id: dhtml_menu.module,v 1.27 2008-06-30 14:49:06 arancaytar Exp $

/**
 * @file dhtml_menu.module
 * Allow click expansion of the menu tree via javascript, with
 * graceful degradation.
 */

define('DHTML_MENU_DUPLICATE_DEFAULT', "admin\nadmin/build/menu\nnode/add");

/**
 * Implementation of hook_menu().
 */
function dhtml_menu_menu() {
  $items['admin/settings/dhtml_menu'] = array(
    'title'            => 'DHTML Menu',
    'description'      => 'Adds new menus with DHTML to reduce page refreshes',
    'page callback'    => 'drupal_get_form',
    'page arguments'   => array('dhtml_menu_settings'),
    'access arguments' => array('administer site configuration'),
    'file'             => 'dhtml_menu.admin.inc',
  );

  return $items;
}

/**
 * Implementation of hook_form_alter().
 * @ingroup form
 */
function dhtml_menu_form_block_admin_configure_alter(&$form, $form_state) {
  // Modify the form if it is a menu or the navigation block.
  if ($form['module']['#value'] == 'menu' || ($form['module']['#value'] == 'user' && $form['delta']['#value'] == 1)) {
    $dhtml = variable_get('dhtml_menu_menus', array());
    
    $form['dhtml_menu'] = array(
      '#default_value'  => !empty($dhtml[$form['module']['#value']][$form['delta']['#value']]),
      '#title'          => t('Use the DHTML effect'),
      '#type'           => 'checkbox',
      '#weight'         => -3,
    );
    $form['#submit']['_dhtml_menu_form_block_submit'] = '_dhtml_menu_form_block_submit';
  }
}

/**
 * Save the DHTML options
 *
 * @ingroup form
 */
function _dhtml_menu_form_block_submit(&$form, $form_state) {
  $dhtml = variable_get('dhtml_menu_menus', array());
  $dhtml[$form_state['values']['module']][$form_state['values']['delta']] = $form_state['values']['dhtml_menu'];
  variable_set('dhtml_menu_menus', $dhtml);
}

/**
 * Implementation of hook_preprocess().
 * Change the normal behaviour ('theming') of hook_block().
 *
 * @ingroup themable
 */
function dhtml_menu_preprocess_block(&$variables) {
  $delta = $variables['block']->delta;
  $module = $variables['block']->module;
  $dhtml = variable_get('dhtml_menu_menus', array());
  
  // If the menu has the DHTML menu option enabled,
  // replace the entire block content with its DHTML equivalent
  if (!empty($dhtml[$module][$delta])) {
    $variables['block']->content = _dhtml_menu_build_block($module, $delta);
  }
}

/** 
 * Build a specific DHTML Menu block's content.
 */
function _dhtml_menu_build_block($module, $delta) {
  $menu_name = $module == 'user' ? 'navigation' : $delta;
  // Retrieve menu tree data and build a DHTML menu from it.
  return theme('dhtml_menu_tree', menu_tree_all_data($menu_name));
}

/**
 * Implementation of hook_theme().
 */
function dhtml_menu_theme($existing, $type) {
  $theme['dhtml_menu_item'] = array(
    'file'      => 'dhtml_menu.theme.inc',
    'arguments' => array('item' => array(), 'id' => NULL),
  );
  $theme['dhtml_menu_tree'] = array(
    'file'      => 'dhtml_menu.theme.inc',
    'arguments' => array('tree' => array(), 'parent' => NULL, 'pid' => NULL),
  );
  return $theme;
}