<?php
// $Id: uc_cart.module,v 1.15.2.36 2010/08/11 15:09:54 islandusurper Exp $

/**
 * @file
 * Handles all things concerning Ubercart's shopping cart.
 *
 * The Ubercart cart system functions much like the e-commerce cart at its base
 * level... in fact, most carts do.  This module handles the cart display,
 * adding items to a cart, and checking out.  The module enables the cart,
 * products, and checkout to be extensible.
 */

require_once('uc_cart_checkout_pane.inc');
require_once('uc_cart.ca.inc');

/*******************************************************************************
 * Hook Functions (Drupal)
 ******************************************************************************/

/**
 * Implementation of hook_menu().
 */
function uc_cart_menu() {
  $items = array();

  $items['admin/store/settings/cart'] = array(
    'title' => 'Cart settings',
    'description' => 'Configure the cart settings.',
    'page callback' => 'uc_cart_cart_settings_overview',
    'access arguments' => array('administer store'),
    'file' => 'uc_cart.admin.inc',
  );
  $items['admin/store/settings/cart/overview'] = array(
    'title' => 'Overview',
    'description' => 'View the cart settings.',
    'access arguments' => array('administer store'),
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['admin/store/settings/cart/edit'] = array(
    'title' => 'Edit',
    'description' => 'Edit the cart settings.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_cart_cart_settings_form'),
    'access arguments' => array('administer store'),
    'type' => MENU_LOCAL_TASK,
    'weight' => -5,
    'file' => 'uc_cart.admin.inc',
  );
  $items['admin/store/settings/cart/edit/basic'] = array(
    'title' => 'Cart settings',
    'description' => 'Edit the basic cart settings.',
    'access arguments' => array('administer store'),
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['admin/store/settings/cart/edit/panes'] = array(
    'title' => 'Cart panes',
    'description' => 'Edit the pane settings for the cart view page.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_cart_cart_panes_form'),
    'access arguments' => array('administer store'),
    'type' => MENU_LOCAL_TASK,
    'weight' => -5,
    'file' => 'uc_cart.admin.inc',
  );
  $items['admin/store/settings/cart/edit/block'] = array(
    'title' => 'Cart block',
    'description' => 'Edit the settings for the shopping cart block.',
    'page callback' => 'uc_cart_block_edit_info',
    'access arguments' => array('administer store'),
    'type' => MENU_LOCAL_TASK,
    'weight' => 0,
    'file' => 'uc_cart.admin.inc',
  );

  $items['admin/store/settings/checkout'] = array(
    'title' => 'Checkout settings',
    'description' => 'Configure the checkout settings.',
    'page callback' => 'uc_cart_checkout_settings_overview',
    'access arguments' => array('administer store'),
    'file' => 'uc_cart.admin.inc',
  );
  $items['admin/store/settings/checkout/overview'] = array(
    'title' => 'Overview',
    'description' => 'View the checkout settings.',
    'access arguments' => array('administer store'),
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
    'file' => 'uc_cart.admin.inc',
  );
  $items['admin/store/settings/checkout/edit'] = array(
    'title' => 'Edit',
    'description' => 'Edit the cart settings.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_cart_checkout_settings_form'),
    'access arguments' => array('administer store'),
    'type' => MENU_LOCAL_TASK,
    'weight' => -5,
    'file' => 'uc_cart.admin.inc',
  );
  $items['admin/store/settings/checkout/edit/basic'] = array(
    'title' => 'Checkout settings',
    'description' => 'Edit the basic checkout settings.',
    'access arguments' => array('administer store'),
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['admin/store/settings/checkout/edit/panes'] = array(
    'title' => 'Checkout panes',
    'description' => 'Edit the pane settings for the checkout page.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_cart_checkout_panes_form'),
    'access arguments' => array('administer store'),
    'type' => MENU_LOCAL_TASK,
    'weight' => -5,
    'file' => 'uc_cart.admin.inc',
  );
  $items['admin/store/settings/checkout/edit/messages'] = array(
    'title' => 'Checkout messages',
    'description' => 'Edit the messages for the checkout completion page.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_cart_checkout_messages_form'),
    'access arguments' => array('administer store'),
    'type' => MENU_LOCAL_TASK,
    'weight' => 0,
    'file' => 'uc_cart.admin.inc',
  );
  $items['admin/store/settings/checkout/edit/fields'] = array(
    'title' => 'Address fields',
    'description' => 'Edit the address field settings.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_store_address_fields_form'), // missing?
    'access arguments' => array('administer store'),
    'type' => MENU_LOCAL_TASK,
    'weight' => 5,
    'file' => 'uc_cart.admin.inc',
  );

  $items['cart'] = array(
    'title' => 'Shopping cart',
    'description' => 'View/modify the contents of your shopping cart or proceed to checkout.',
    'page callback' => 'uc_cart_view',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
    'file' => 'uc_cart.pages.inc',
  );
  $items['cart/checkout'] = array(
    'title' => 'Checkout',
    'description' => 'Purchase the items in your shopping cart.',
    'page callback' => 'uc_cart_checkout',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
    'file' => 'uc_cart.pages.inc',
  );
  $items['cart/checkout/review'] = array(
    'title' => 'Review order',
    'description' => 'Review an order before final submission.',
    'page callback' => 'uc_cart_checkout_review',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
    'file' => 'uc_cart.pages.inc',
  );
  $items['cart/checkout/complete'] = array(
    'title' => 'Order complete',
    'description' => 'Display information upon completion of an order.',
    'page callback' => 'uc_cart_checkout_complete',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
    'file' => 'uc_cart.pages.inc',
  );

  return $items;
}

/**
 * Implementation of hook_imagecache_default_presets().
 */
function uc_cart_imagecache_default_presets() {
  $presets = array();

  $presets['cart'] = array(
    'presetname' => 'cart',
    'actions' => array(
      array(
        'weight' => '0',
        'module' => 'uc_cart',
        'action' => 'imagecache_scale',
        'data' => array(
          'width' => '50',
          'height' => '50',
          'upscale' => 0,
        ),
      ),
    ),
  );

  return $presets;
}

/**
 * Implementation of hook_theme().
 */
function uc_cart_theme() {
  return array(
    'uc_cart_block_title' => array(
      'arguments' => array('title' => NULL, 'icon_class' => FALSE, 'collapsible' => FALSE),
    ),
     'uc_cart_block_title_icon' => array(
      'arguments' => array('icon_class' => NULL),
     ),
     'uc_cart_block_content_cachable' => array(
       'arguments' => array(),
     ),
     'uc_cart_block_content' => array(
      'arguments' => array('help_text' => NULL, 'items' => NULL, 'item_count' => NULL, 'item_text' => NULL, 'total' => NULL, 'summary_links' => NULL),
     ),
     'uc_cart_block_items' => array(
      'arguments' => array('items' => NULL),
     ),
     'uc_cart_block_summary' => array(
      'arguments' => array('item_count' => NULL, 'item_text' => NULL, 'total' => NULL, 'summary_links' => NULL),
     ),
    'uc_empty_cart' => array(
      'arguments' => array(),
    ),
    'uc_cart_view_form' => array(
      'arguments' => array('form' => NULL),
    ),
    'uc_cart_view_price' => array(
      'arguments' => array('form' => NULL),
    ),
    'address_pane' => array(
      'arguments' => array('form' => NULL),
    ),
    'cart_review_table' => array(
      'arguments' => array('show_subtotal' => TRUE),
    ),
    'uc_cart_checkout_form' => array(
      'arguments' => array('form' => NULL),
      'file' => 'uc_cart.pages.inc',
    ),
    'uc_cart_checkout_review' => array(
      'arguments' => array('panes' => NULL, 'form' => NULL),
      'file' => 'uc_cart.pages.inc',
    ),
    'uc_cart_complete_sale' => array(
      'arguments' => array('message' => ''),
    ),
  );
}

/**
 * Implementation of hook_init().
 */
function uc_cart_init() {
  global $conf;
  $conf['i18n_variables'][] = 'uc_cart_breadcrumb_text';
  $conf['i18n_variables'][] = 'uc_cart_help_text';
  $conf['i18n_variables'][] = 'uc_cart_new_account_details';
  $conf['i18n_variables'][] = 'uc_checkout_instructions';
  $conf['i18n_variables'][] = 'uc_checkout_review_instructions';
  $conf['i18n_variables'][] = 'uc_continue_shopping_text';
  $conf['i18n_variables'][] = 'uc_minimum_subtotal_text';
  $conf['i18n_variables'][] = 'uc_msg_continue_shopping';
  $conf['i18n_variables'][] = 'uc_msg_order_existing_user';
  $conf['i18n_variables'][] = 'uc_msg_order_logged_in';
  $conf['i18n_variables'][] = 'uc_msg_order_new_user';
  $conf['i18n_variables'][] = 'uc_msg_order_submit';
}

/**
 * Implementation of hook_cron().
 */
function uc_cart_cron() {
  // Empty anonymous carts.
  $time = strtotime(variable_get('uc_cart_anon_duration', '4') .' '. variable_get('uc_cart_anon_unit', 'hours') .' ago');
  $result = db_query("SELECT DISTINCT cart_id FROM {uc_cart_products} WHERE changed <= %d AND CHAR_LENGTH(cart_id) > 8", $time);
  while ($row = db_fetch_object($result)) {
    uc_cart_empty($row->cart_id);
  }

  // Empty authenticated carts.
  $time = strtotime(variable_get('uc_cart_auth_duration', '1') .' '. variable_get('uc_cart_auth_unit', 'years') .' ago');
  $result = db_query("SELECT DISTINCT cart_id FROM {uc_cart_products} WHERE changed <= %d AND CHAR_LENGTH(cart_id) <= 8", $time);
  while ($row = db_fetch_object($result)) {
    uc_cart_empty($row->cart_id);
  }
}

/**
 * Implementation of hook_exit().
 *
 * Code from CacheExclude - http://drupal.org/project/cacheexclude
 */
function uc_cart_exit() {
  global $base_root;

  $pages = array('cart', 'cart/checkout', 'cart/checkout/review', 'cart/checkout/complete');
  $this_page = request_uri();
  foreach ($pages as $page) {
    if ($page && strstr($this_page, $page) !== FALSE) {
      cache_clear_all($base_root . $this_page, 'cache_page');
      return;
    }
  }
}

/**
 * Implementation of hook_nodeapi().
 */
function uc_cart_nodeapi(&$node, $op, $arg3, $arg4) {
  if (uc_product_is_product($node->type)) {
    switch ($op) {
      case 'delete':
        db_query("DELETE FROM {uc_cart_products} WHERE nid = %d", $node->nid);
      break;
    }
  }
}

/**
 * Implementation of hook_user().
 */
function uc_cart_user($op, &$edit, &$user, $category = NULL) {
  switch ($op) {
    case 'load':
      // Fall through if this a new user load prior to checkout.
      if (request_uri() != '/user/register?destination=cart/checkout' || $user->uid == 0) {
        break;
      }
    case 'login':
      // Add items from an anonymous cart to a user's permanent cart on login.
      uc_cart_login_update($user->uid);
      break;
  }
}

/**
 * Implementation of hook_form_alter().
 */
function uc_cart_form_alter(&$form, $form_state, $form_id) {
  global $language;

  // Redirect shopper back to checkout page if they go to login from there.
  if ($form_id == 'user_login' || $form_id == 'user_edit' || $form_id == 'user_register') {

    // Figure out the destination.
    if (empty($_SESSION['checkout-redirect'])) {
      // Compare the referer to checkout page URLs.
      if (uc_referer_check('cart/checkout') && uc_referer_uri() != '') {
        $_SESSION['checkout-redirect'] = TRUE;
      }
      elseif (uc_referer_check(array('cart/checkout/review', 'cart/checkout/complete')) && uc_referer_uri() != '') {
        unset($_SESSION['checkout-redirect']);
      }
    }

    if (!empty($_SESSION['checkout-redirect'])) {
      $form['#redirect'] = 'cart/checkout';
    }
  }

  if ($form_id == 'user_login' || $form_id == 'user_login_block') {
    $form['#submit'] = array_merge(array('uc_cart_user_login_form_submit'), (array) $form['#submit']);
  }
}

/**
 * Implementation of hook_block().
 */
function uc_cart_block($op = 'list', $delta = 0, $edit = array()) {
  global $user;

  switch ($op) {
    case 'list':
      $blocks = array();

      // TODO: Add sensible default settings for the cart block based on the
      // docs at http://api.drupal.org/api/function/hook_block/6.
      $blocks[0] = array(
        'info' => t('Shopping cart'),
        'cache' => BLOCK_NO_CACHE,
      );

      return $blocks;

    case 'configure':
      // 0 = Default shopping cart block.
      if ($delta == 0) {
        return uc_cart_block_settings_form();
      }
      break;

    case 'save':
      // 0 = Default shopping cart block.
      if ($delta == 0) {
        uc_cart_block_settings_form_submit($edit);
      }
      break;

    case 'view':
      // 0 = Default shopping cart block.
      if ($delta == 0) {
        $cachable = !$user->uid && variable_get('cache', CACHE_DISABLED) != CACHE_DISABLED;
        $uc_cart_path = drupal_get_path('module', 'uc_cart');
        $product_count = count(uc_cart_get_contents());

        // Display nothing if the block is set to hide on empty and there are no
        // items in the cart.
        if (!$cachable && variable_get('uc_cart_block_empty_hide', FALSE) && !$product_count) {
          return;
        }

        // Add the cart block CSS.
        drupal_add_css(drupal_get_path('module', 'uc_cart') .'/uc_cart_block.css');

        // If the block is collapsible, add the appropriate JS.
        if (!$cachable && variable_get('uc_cart_block_collapsible', TRUE)) {
          drupal_add_js(array('ucCollapsedBlock' => variable_get('uc_cart_block_collapsed', TRUE)), 'setting');
          drupal_add_js(drupal_get_path('module', 'uc_cart') .'/uc_cart_block.js');
          $collapsible = TRUE;
        }
        else {
          $collapsible = FALSE;
        }

        // Hack in some CSS to hide the block if necessary. drupal_add_css() is in Drupal 7 for this...
        if (variable_get('uc_cart_block_collapsed', TRUE)) {
          drupal_set_html_head("<style type='text/css'>#cart-block-contents { display: none; }</style>");
        }

        // Build the cart image if enabled.
        if (variable_get('uc_cart_block_image', TRUE)) {
          // If the cart is empty or we need a cachable cart block...
          if ($cachable || !$product_count) {
            // Use the "empty" cart icon.
            $icon_class = 'cart-block-icon-empty';
          }
          else {
            // Otherwise use the "full" cart icon.
            $icon_class = 'cart-block-icon-full';
          }
        }
        else {
          $icon_class = FALSE;
        }

        // Set the text of the block title.
        $title = check_plain(trim(variable_get('uc_cart_block_title', '')));

        if (empty($title)) {
          $title = t('Shopping cart');
        }

        // Build the block array for display based on cache settings.
        if ($cachable) {
          // Caching is turned on and the user is not logged in, so we should
          // deliver a block that is safe for caching.
          $block = array(
            'subject' => theme('uc_cart_block_title', $title, $icon_class, $collapsible),
            'content' => theme('uc_cart_block_content_cachable'),
          );
        }
        else {
          // Otherwise build the whole shebang.

          // First build the help text.
          $help_text = FALSE;

          if (variable_get('uc_cart_show_help_text', FALSE) && ($text = variable_get('uc_cart_help_text', t('Click title to display cart contents.')))) {
            $help_text = check_plain($text);
          }

          $items = FALSE;
          $item_count = 0;
          $total = 0;

          if ($product_count) {
            foreach (uc_cart_get_contents() as $item) {
              $display_item = module_invoke($item->module, 'cart_display', $item);

              if (!empty($display_item)) {
                $items[] = array(
                  'nid' => $display_item['nid']['#value'],
                  'qty' => t('@qty&times;', array('@qty' => $display_item['qty']['#default_value'])),
                  'title' => $display_item['title']['#value'],
                  'price' => $display_item['#total'],
                  'desc' => isset($display_item['description']['#value']) ? $display_item['description']['#value'] : FALSE,
                );
              }

              $item_count += $item->qty;
              $total += $display_item['#total'];
            }
          }

          // Build the item count text and cart links.
          $item_text = format_plural($item_count, '<span class="num-items">@count</span> Item', '<span class="num-items">@count</span> Items');

          $summary_links = array(
            'cart-block-view-cart' => array(
              'title' => t('View cart'),
              'href' => 'cart',
              'attributes' => array('rel' => 'nofollow'),
            ),
          );

          // Only add the checkout link if checkout is enabled.
          if (variable_get('uc_checkout_enabled', TRUE)) {
            $summary_links['cart-block-checkout'] = array(
              'title' => t('Checkout'),
              'href' => 'cart/checkout',
              'attributes' => array('rel' => 'nofollow'),
            );
          }

          $block = array(
            'subject' => theme('uc_cart_block_title', $title, $icon_class, $collapsible),
            'content' => theme('uc_cart_block_content', $help_text, $items, $item_count, $item_text, $total, $summary_links),
          );
        }

        return $block;
      }
      break;
  }
}

/**
 * Build the settings form used by the shopping cart block.
 *
 * @ingroup forms
 * @see uc_cart_block_settings_form_submit()
 */
function uc_cart_block_settings_form() {
  $form = array();

  $form['uc_cart_block_empty_hide'] = array(
    '#type' => 'checkbox',
    '#title' => t('Hide block if cart is empty.'),
    '#default_value' => variable_get('uc_cart_block_empty_hide', FALSE),
  );
  $form['uc_cart_block_image'] = array(
    '#type' => 'checkbox',
    '#title' => t('Display the shopping cart icon in the block title.'),
    '#default_value' => variable_get('uc_cart_block_image', TRUE),
  );
  $form['uc_cart_block_title'] = array(
    '#type' => 'textfield',
    '#title' => t('Cart name'),
    '#description' => t('This name will be displayed when using the default block title.<br />Leaving this blank defaults to the translatable name "Shopping Cart."'),
    '#default_value' => variable_get('uc_cart_block_title', ''),
  );
  $form['uc_cart_block_collapsible'] = array(
    '#type' => 'checkbox',
    '#title' => t('Make the shopping cart block collapsible by clicking the name or arrow.'),
    '#default_value' => variable_get('uc_cart_block_collapsible', TRUE),
  );
  $form['uc_cart_block_collapsed'] = array(
    '#type' => 'checkbox',
    '#title' => t('Display the shopping cart block collapsed by default.'),
    '#default_value' => variable_get('uc_cart_block_collapsed', TRUE),
  );
  $form['uc_cart_show_help_text'] = array(
    '#type' => 'checkbox',
    '#title' => t('Display small help text in the shopping cart block.'),
    '#default_value' => variable_get('uc_cart_show_help_text', FALSE),
  );
  $form['uc_cart_help_text'] = array(
    '#type' => 'textfield',
    '#title' => t('Cart help text'),
    '#description' => t('Displayed if the above box is checked.'),
    '#default_value' => variable_get('uc_cart_help_text', t('Click title to display cart contents.')),
    '#size' => 32,
  );

  return $form;
}

/**
 * Save the shopping cart block settings.
 *
 * @see uc_cart_block_settings_form()
 */
function uc_cart_block_settings_form_submit($edit = array()) {
  variable_set('uc_cart_block_empty_hide', $edit['uc_cart_block_empty_hide']);
  variable_set('uc_cart_block_image', $edit['uc_cart_block_image']);
  variable_set('uc_cart_block_title', $edit['uc_cart_block_title']);
  variable_set('uc_cart_block_collapsible', $edit['uc_cart_block_collapsible']);
  variable_set('uc_cart_block_collapsed', $edit['uc_cart_block_collapsed']);
  variable_set('uc_cart_show_help_text', $edit['uc_cart_show_help_text']);
  variable_set('uc_cart_help_text', $edit['uc_cart_help_text']);
}

/**
 * Theme the shopping cart block title
 *
 * @param $title
 *   The text to use for the title of the block.
 * @param $icon_class
 *   Class to use for the cart icon image or FALSE if the icon is disabled.
 * @param $collapsible
 *   TRUE or FALSE indicating whether or not the cart block is collapsible.
 * @ingroup themeable
 */
function theme_uc_cart_block_title($title, $icon_class = 'cart-empty', $collapsible = TRUE) {
  $output = '';

  // Add in the cart image if specified.
  if ($icon_class) {
    $output .= theme('uc_cart_block_title_icon', $icon_class);
  }

  // Add the main title span and text, with or without the arrow based on the
  // cart block collapsibility settings.
  if ($collapsible) {
    $output .= '<span class="cart-block-title-bar" title="'. t('Show/hide shopping cart contents.') .'">'. $title .'<span class="cart-block-arrow"></span></span>';
  }
  else {
    $output .= '<span class="cart-block-title-bar">'. $title .'</span>';
  }

  return $output;
}

/**
 * Theme the shopping cart icon.
 *
 * @param $icon_class
 *   Class to use for the cart icon image, either cart-full or cart-empty.
 * @ingroup themeable
 */
function theme_uc_cart_block_title_icon($icon_class) {
  return l('<span class="'. $icon_class .'" title="'. t('View your shopping cart.') .'"></span>', 'cart', array('html' => TRUE));
}

 /**
 * Theme the cachable shopping cart block content.
 *
 * @ingroup themeable
 */
function theme_uc_cart_block_content_cachable() {
  return t('<a href="!url">View</a> your shopping cart.', array('!url' => url('cart')));
}

/**
 * Theme the shopping cart block content.
 *
 * @param $help_text
 *   Text to place in the small help text area beneath the cart block title or
 *     FALSE if disabled.
 * @param $items
 *   An associative array of item information containing the keys 'qty',
 *      'title', 'price', and 'desc'.
 * @param $item_count
 *   The number of items in the shopping cart.
 * @param $item_text
 *   A textual representation of the number of items in the shopping cart.
 * @param $total
 *   The unformatted total of all the products in the shopping cart.
 * @param $summary_links
 *   An array of links used in the cart summary.
 * @ingroup themeable
 */
function theme_uc_cart_block_content($help_text, $items, $item_count, $item_text, $total, $summary_links) {
  $output = '';

  // Add the help text if enabled.
  if ($help_text) {
    $output .= '<span class="cart-help-text">'. $help_text .'</span>';
  }

  // Add a wrapper div for use when collapsing the block.
  $output .= '<div id="cart-block-contents">';

  // Add a table of items in the cart or the empty message.
  $output .= theme('uc_cart_block_items', $items);

  $output .= '</div>';

  // Add the summary section beneath the items table.
  $output .= theme('uc_cart_block_summary', $item_count, $item_text, $total, $summary_links);

  return $output;
}

/**
 * Theme the table listing the items in the shopping cart block.
 *
 * @param $items
 *   An associative array of item information containing the keys 'qty',
 *      'title', 'price', and 'desc'.
 * @ingroup themeable
 */
function theme_uc_cart_block_items($items) {
  // If there are items in the shopping cart...
  if ($items) {
    $output = '<table class="cart-block-items"><tbody>';
    $row_class = 'odd';

    $context = array(
      'revision' => 'themed',
      'type' => 'price',
    );

    // Loop through each item.
    foreach ($items as $item) {
      $context['subject'] = array(
        'cart_item' => $item,
        'node' => node_load($item->nid),
      );
      // Add the basic row with quantity, title, and price.
      $output .= '<tr class="'. $row_class .'"><td class="cart-block-item-qty">'. $item['qty'] .'</td>'
                .'<td class="cart-block-item-title">'. $item['title'] .'</td>'
                .'<td class="cart-block-item-price">'. uc_price($item['price'], $context) .'</td></tr>';

      // Add a row of description if necessary.
      if ($item['desc']) {
        $output .= '<tr class="'. $row_class .'"><td colspan="3" class="cart-block-item-desc">'. $item['desc'] .'</td></tr>';
      }

      // Alternate the class for the rows.
      $row_class = ($row_class == 'odd') ? 'even' : 'odd';
    }

    $output .= '</tbody></table>';
  }
  else {
    // Otherwise display an empty message.
    $output = '<p>'. t('There are no products in your shopping cart.') .'</p>';
  }

  return $output;
}

/**
 * Theme the summary table at the bottom of the default shopping cart block.
 *
 * @param $item_count
 *   The number of items in the shopping cart.
 * @param $item_text
 *   A textual representation of the number of items in the shopping cart.
 * @param $total
 *   The unformatted total of all the products in the shopping cart.
 * @param $summary_links
 *   An array of links used in the summary.
 * @ingroup themeable
 */
function theme_uc_cart_block_summary($item_count, $item_text, $total, $summary_links) {
  $context = array(
    'revision' => 'themed-original',
    'type' => 'amount',
  );
  // Build the basic table with the number of items in the cart and total.
  $output = '<table class="cart-block-summary"><tbody><tr>'
           .'<td class="cart-block-summary-items">'. $item_text .'</td>'
           .'<td class="cart-block-summary-total"><label>'. t('Total:')
           .'</label> '. uc_price($total, $context) .'</td></tr>';

  // If there are products in the cart...
  if ($item_count > 0) {
    // Add a view cart link.
    $output .= '<tr class="cart-block-summary-links"><td colspan="2">'
             . theme('links', $summary_links) .'</td></tr>';
  }

  $output .= '</tbody></table>';

  return $output;
}


/*******************************************************************************
 * Hook Functions (Ubercart)
 ******************************************************************************/

/**
 * Implementation of hook_uc_message().
 */
function uc_cart_uc_message() {
  global $user;

  $messages['checkout_instructions'] = '';
  $messages['review_instructions'] = t("Your order is almost complete. Please review the details below and click 'Submit order' if all the information is correct.  You may use the 'Back' button to make changes to your order if necessary.");
  $messages['completion_message'] = t('Your order is complete! Your order number is [order-id].');
  $messages['completion_logged_in'] = t('Thank you for shopping at [store-name]. While logged in, you may continue shopping or <a href="[order-url]">view your current order status</a> and order history.');
  $messages['completion_existing_user'] = t("Thank you for shopping at [store-name]. Your current order has been attached to the account we found matching your e-mail address.\n\n<a href=\"!user_url\">Login</a> to view your current order status and order history. Remember to login when you make your next purchase for a faster checkout experience!", array('!user_url' => url('user')));
  $messages['completion_new_user'] = t("Thank you for shopping at [store-name]. A new account has been created for you here that you may use to view your current order status.\n\n<a href=\"!user_url\">Login</a> to your new account using the following information:\n\n<strong>Username:</strong> !new_username\n<strong>Password:</strong> !new_password", array('!user_url' => url('user')));
  $messages['continue_shopping'] = t('<a href="[site-url]">Return to the front page.</a>');

  return $messages;
}

/**
 * Implementation of hook_cart_pane().
 */
function uc_cart_cart_pane($items) {
  $panes[] = array(
    'id' => 'cart_form',
    'title' => t('Default cart form'),
    'enabled' => TRUE,
    'weight' => 0,
    'body' => !is_null($items) ? '<div id="cart-form-pane">'. drupal_get_form('uc_cart_view_form', $items) .'</div>': '',
  );

  return $panes;
}

/**
 * Implementation of hook_checkout_pane().
 */
function uc_cart_checkout_pane() {
  $panes[] = array(
    'id' => 'cart',
    'callback' => 'uc_checkout_pane_cart',
    'title' => t('Cart contents'),
    'desc' => t("Display the contents of a customer's shopping cart."),
    'weight' => 1,
    'process' => FALSE,
    'collapsible' => FALSE,
  );
  $panes[] = array(
    'id' => 'customer',
    'callback' => 'uc_checkout_pane_customer',
    'title' => t('Customer information'),
    'desc' => t('Get the necessary information to create a customer on the site.'),
    'weight' => 2,
  );
  $panes[] = array(
    'id' => 'delivery',
    'callback' => 'uc_checkout_pane_delivery',
    'title' => t('Delivery information'),
    'desc' => t('Get the information for where the order needs to ship.'),
    'weight' => 3,
    'shippable' => TRUE,
  );
  $panes[] = array(
    'id' => 'billing',
    'callback' => 'uc_checkout_pane_billing',
    'title' => t('Billing information'),
    'desc' => t('Get basic information needed to collect payment.'),
    'weight' => 4,
  );
  $panes[] = array(
    'id' => 'comments',
    'callback' => 'uc_checkout_pane_comments',
    'title' => t('Order comments'),
    'desc' => t('Allow a customer to put comments on an order.'),
    'weight' => 7,
  );

  return $panes;
}

/*******************************************************************************
 * Callback Functions, Forms, and Tables
 ******************************************************************************/

/**
 * When a user logs in, update their cart items before the session changes.
 */
function uc_cart_user_login_form_submit($form, &$form_state) {
  global $user;
  unset($_SESSION['checkout-redirect']);
  uc_cart_login_update($user->uid);
}

/**
 * Update a user's cart to include items from their anonymous session.
 */
function uc_cart_login_update($uid) {
  // Get the current contents of the cart.
  $items = uc_cart_get_contents($uid);

  // Update the cart so the ID is switched from the session to user ID.
  db_query("UPDATE {uc_cart_products} SET cart_id = %d WHERE cart_id = '%s'", $uid, $_SESSION['uc_cart_id']);

  // If there were items before the update, we need to re-add them all to
  // take care of item consolidation.
  if (count($items) > 0) {
    // Store again what items these are.
    $items = uc_cart_get_contents($uid, 'rebuild');

    // Remove from the table all the items in the cart.
    // Should be a function call instead of a single query. -RS
    db_query("DELETE FROM {uc_cart_products} WHERE cart_id = '%s'", $uid);

    // Reset the cart item cache.
    uc_cart_get_contents($uid, 'rebuild');

    // Loop through what the items should be and re-add them to the cart.
    foreach ($items as $key => $item) {
      uc_cart_add_item($item->nid, $item->qty, $item->data, $uid, FALSE, FALSE, FALSE);
    }

    // Unset the anonymous cart ID, it's no longer needed
    unset($_SESSION['uc_cart_id']);

    // Rebuild the cart item cache.
    uc_cart_get_contents($uid, 'rebuild');
  }
}

/**
 * Return the text displayed for an empty shopping cart.
 *
 * @ingroup themeable
 */
function theme_uc_empty_cart() {
  return '<p>'. t('There are no products in your shopping cart.') .'</p>';
}

/**
 * Display a page allowing the customer to view the contents of his or her cart.
 *
 * Handles simple or complex objects. Some cart items may have a list of products
 * that they represent. These are displayed but are not able to be changed by the
 * customer.
 *
 * @ingroup forms
 * @see
 *   uc_cart_view_form_submit()
 *   theme_uc_cart_view_form()
 *   theme_uc_cart_view_price()
 *   uc_cart_view_table()
 */
function uc_cart_view_form($form_state, $items = NULL) {
  $form['items'] = array(
    '#type' => 'tapir_table',
    '#tree' => TRUE,
  );

  $context = array(
    'revision' => 'themed-original',
    'type' => 'amount',
  );
  $i = 0;
  foreach ($items as $item) {
    $display_item = module_invoke($item->module, 'cart_display', $item);
    if (!empty($display_item)) {
      $form['items'][$i] = $display_item;
      $form['items'][$i]['image']['#value'] = uc_product_get_picture($display_item['nid']['#value'], 'cart');

      $description = $display_item['title']['#value'] . $display_item['description']['#value'];
      $form['items'][$i]['desc']['#value'] = $description;

      $form['items'][$i]['title']['#type'] = 'value';
      $form['items'][$i]['description']['#type'] = 'value';

      if (empty($display_item['qty'])) {
        $form['items'][$i]['qty'] = array(
          '#value' => '',
        );
      }

      $form['items'][$i]['total'] = array(
        '#value' => uc_price($display_item['#total'], $context),
        '#theme' => 'uc_cart_view_price',
      );
      $i++;
    }
  }

  $form['items'] = tapir_get_table('uc_cart_view_table', $form['items']);

  // If the continue shopping element is enabled...
  if (($cs_type = variable_get('uc_continue_shopping_type', 'link')) !== 'none') {
    // Setup the text used for the element.
    $cs_text = variable_get('uc_continue_shopping_text', '') ? variable_get('uc_continue_shopping_text', '') : t('Continue shopping');

    // Add the element to the form based on the element type.
    if (variable_get('uc_continue_shopping_type', 'link') == 'link') {
      $form['continue_shopping'] = array(
        '#value' => l($cs_text, uc_cart_continue_shopping_url()),
      );
    }
    elseif (variable_get('uc_continue_shopping_type', 'link') == 'button') {
      $form['continue_shopping'] = array(
        '#type' => 'submit',
        '#value' => $cs_text,
        '#submit' => array('uc_cart_view_form_submit'),
      );
      $form['continue_shopping_text'] = array(
        '#type' => 'hidden',
        '#value' => $cs_text,
      );
    }
  }

  // Add the control buttons for updating and proceeding to checkout.
  $form['update'] = array(
    '#type' => 'submit',
    '#value' => t('Update cart'),
    '#submit' => array('uc_cart_view_form_submit'),
  );
  if (variable_get('uc_checkout_enabled', TRUE)) {
    $form['checkout'] = array(
      '#type' => 'submit',
      '#value' => t('Checkout'),
      '#submit' => array('uc_cart_view_form_submit'),
    );
  }

  return $form;
}

/**
 * @see uc_cart_view_form()
 */
function uc_cart_view_form_submit($form, &$form_state) {
  // Remove the cart order variable if the customer came here during checkout.
  if (isset($_SESSION['cart_order'])) {
    unset($_SESSION['cart_order']);
  }

  // Update the items in the shopping cart based on the form values.
  uc_cart_update_item_object((object)$form_state['values']);

  // Specify the appropriate redirect based on the button used to submit.
  switch ($form_state['values']['op']) {
    // Continue shopping button.
    case $form_state['values']['continue_shopping_text']:
      $form_state['redirect'] = uc_cart_continue_shopping_url();
      break;

    // Update cart button.
    case t('Update cart'):
      // No redirect.  Just display a message and preserve the last URL.
      drupal_set_message(t('Your cart has been updated.'));
      break;

    // Checkout button.
    case t('Checkout'):
      $form_state['redirect'] = variable_get('uc_checkout_enabled', TRUE) ? 'cart/checkout' : 'cart';
      break;
  }
}

/**
 * @ingroup themeable
 * @see uc_cart_view_form()
 */
function theme_uc_cart_view_form($form) {
  drupal_add_css(drupal_get_path('module', 'uc_cart') .'/uc_cart.css');

  $output = '<div id="cart-form-products">'
          . drupal_render($form['items']) .'</div>';

  foreach (element_children($form['items']) as $i) {
    foreach (array('title', 'options', 'remove', 'image', 'qty') as $column) {
      $form['items'][$i][$column]['#printed'] = TRUE;
    }
    $form['items'][$i]['#printed'] = TRUE;
  }

  // Add the continue shopping element and cart submit buttons.
  if (($type = variable_get('uc_continue_shopping_type', 'link')) != 'none') {
    // Render the continue shopping element into a variable.
    $cs_element = drupal_render($form['continue_shopping']);

    // Add the element with the appropriate markup based on the display type.
    if ($type == 'link') {
      $output .= '<div id="cart-form-buttons"><div id="continue-shopping-link">'
               . $cs_element .'</div>'. drupal_render($form) .'</div>';
    }
    elseif ($type == 'button') {
      $output .= '<div id="cart-form-buttons"><div id="update-checkout-buttons">'
               . drupal_render($form) .'</div><div id="continue-shopping-button">'
               . $cs_element .'</div></div>';
    }
  }
  else {
    $output .= '<div id="cart-form-buttons">'. drupal_render($form) .'</div>';
  }

  return $output;
}

/**
 * Dumb wrapper function, as the price has been themed by uc_price() already.
 *
 * @ingroup themeable
 * @see uc_cart_view_form()
 */
function theme_uc_cart_view_price($form) {
  return $form['#value'];
}

/**
 * List the products in the cart in a TAPIr table.
 */
function uc_cart_view_table($table) {
  $table['#attributes'] = array('width' => '100%');

  $table['#columns'] = array(
    'remove' => array(
      'cell' => t('Remove'),
      'weight' => 0,
    ),
    'image' => array(
      'cell' => t('Products'),
      'weight' => 1,
    ),
    'desc' => array(
      'cell' => '',
      'weight' => 2,
    ),
    'qty' => array(
      'cell' => t('Qty.'),
      'weight' => 3,
    ),
    'total' => array(
      'cell' => t('Total'),
      'weight' => 4,
    ),
  );

  foreach (element_children($table) as $i) {
    $subtotal += $table[$i]['#total'];

    $table[$i]['remove']['#cell_attributes'] = array('align' => 'center', 'class' => 'remove');
    $table[$i]['image']['#cell_attributes'] = array('class' => 'image');
    $table[$i]['desc']['#cell_attributes'] = array('class' => 'desc');
    $table[$i]['qty']['#cell_attributes'] = array('class' => 'qty');
    $table[$i]['total']['#cell_attributes'] = array('class' => 'price');
    $table[$i]['#attributes'] = array('valign' => 'top');
  }

  $context = array(
    'revision' => 'themed-original',
    'type' => 'amount',
  );
  $table[] = array(
    'total' => array(
      '#value' => '<strong>'. t('Subtotal:') .'</strong> '. uc_price($subtotal, $context),
      '#cell_attributes' => array(
        'colspan' => 'full',
        'align' => 'right',
        'class' => 'subtotal',
      ),
    ),
  );

  return $table;
}


/*******************************************************************************
 * Module and Helper Functions
 ******************************************************************************/

/**
 * Return the URL redirect for the continue shopping element on the cart page.
 *
 * @param $unset
 *   TRUE or FALSE indicating whether or not to unset the last URL variable.
 * @return
 *   The URL or Drupal path that will be used for the continue shopping element.
 */
function uc_cart_continue_shopping_url($unset = TRUE) {
  $url = '';

  // Use the last URL if enabled and available.
  if (variable_get('uc_continue_shopping_use_last_url', TRUE)) {
    $url = $_SESSION['uc_cart_last_url'];
  }

  // If the URL is still empty, fall back to the default.
  if (empty($url)) {
    $url = variable_get('uc_continue_shopping_url', '');
  }

  // Unset the last URL if specified.
  if ($unset) {
    unset($_SESSION['uc_cart_last_url']);
  }

  return $url;
}

/**
 * Complete a sale, including adjusting order status and creating user account.
 *
 * @param $order
 *   The order object that has just been completed.
 * @param $login
 *   Whether or not to login a new user when this function is called.
 * @return
 *   The HTML text of the default order completion page.
 */
function uc_cart_complete_sale($order, $login = FALSE) {
  global $user;

  // Logic to create new user if necessary:
  if ($order->uid == 0) {
    // Check for an existing user account with the e-mail address from checkout.
    $result = db_query("SELECT uid FROM {users} WHERE mail = '%s'", $order->primary_email);

    // If it was found, update the order.
    if ($account = db_fetch_object($result)) {
      $order->uid = $account->uid;
      $account = user_load($account->uid);
      db_query("UPDATE {uc_orders} SET uid = %d WHERE order_id = %d", $order->uid, $order->order_id);
      $message_type = 'existing_user';
    }
    else {
      // Get a valid new username.
      if (empty($order->data['new_user']['name'])) {
        $name = uc_store_email_to_username($order->primary_email);
      }
      else {
        $name = $order->data['new_user']['name'];
      }

      // Setup the account fields array and save it as a new user.
      $fields = array(
        'name' => $name,
        'mail' => $order->primary_email,
        'init' => $order->primary_email,
        'pass' => empty($order->data['new_user']['pass']) ? user_password(variable_get('uc_pwd_length', 6)) : $order->data['new_user']['pass'],
        'roles' => array(),
        'status' => variable_get('uc_new_customer_status_active', TRUE) ? 1 : 0,
      );
      $account = user_save('', $fields);

      // Send the customer their account details if enabled.
      if (variable_get('uc_new_customer_email', TRUE)) {
        // Manually set the password so it appears in the e-mail.
        $account->password = $fields['pass'];

        // Send the e-mail through the user module.
        drupal_mail('user', 'register_no_approval_required', $order->primary_email, NULL, array('account' => $account), uc_store_email_from());
      }

      // Store the login details in the session for use on the page display.
      $_SESSION['new_user'] = array('name' => $fields['name'], 'pass' => $fields['pass']);

      // Update the order's uid in this request and in the database.
      $order->uid = $account->uid;
      unset($order->data['new_user']['pass']);
      db_query("UPDATE {uc_orders} SET uid = %d, data = '%s' WHERE order_id = %d", $order->uid, serialize($order->data), $order->order_id);

      // Login the user if specified.
      if ($login) {
        $form_state = array('values' => $fields);
        drupal_execute('user_login', $form_state);
      }

      $message_type = 'new_user';
    }
  }
  else {
    if ($order->uid == $user->uid) {
      $message_type = 'logged_in';
      $account = clone $user;
    }
    else {
      $message_type = 'existing_user';
      $account = user_load($order->uid);
    }
  }

  $messages['uc_msg_order_submit_format'] = variable_get('uc_msg_order_submit', uc_get_message('completion_message'));
  $message = variable_get('uc_msg_order_'.$message_type, uc_get_message('completion_'.$message_type));
  if ($message != '') {
    $variables['!new_username'] = check_plain($_SESSION['new_user']['name']);
    $variables['!new_password'] = check_plain($_SESSION['new_user']['pass']);
    $messages['uc_msg_order_'.$message_type.'_format'] = strtr($message, $variables);
  }
  $messages['uc_msg_continue_shopping_format'] = variable_get('uc_msg_continue_shopping', uc_get_message('continue_shopping'));

  $output_message = '';
  foreach ($messages as $format => $message) {
    $message = token_replace_multiple($message, array('global' => NULL, 'order' => $order));
    $message = check_markup($message, variable_get($format, FILTER_FORMAT_DEFAULT), FALSE);
    $output_message .= $message;
  }
  $themed_output = theme('uc_cart_complete_sale', $output_message);

  // Move an order's status from "In Checkout" to "Pending"
  $status = db_result(db_query("SELECT order_status FROM {uc_orders} WHERE order_id = %d", $order->order_id));
  if (uc_order_status_data($status, 'state') == 'in_checkout') {
    uc_order_update_status($order->order_id, uc_order_state_default('post_checkout'));
  }

  // Empty that cart...
  uc_cart_empty(uc_cart_get_id());

  // Clear our the session variables used to force the cart workflow.
  unset($_SESSION['cart_order'], $_SESSION['do_complete'], $_SESSION['new_user']);

  module_invoke_all('uc_checkout_complete', $order, $account);
  ca_pull_trigger('uc_checkout_complete', $order, $account);

  return $themed_output;
}

/**
 * Theme the sale completion page.
 *
 * @param $message
 *   Message containing order number info, account info, and link to continue shopping.
 * @ingroup themeable
 */
function theme_uc_cart_complete_sale($message) {
  return $message;
}

/**
 * Return the unique cart_id of the user.
 *
 * @param $create
 * Toggle auto creation of cart id.
 * @return
 * Cart id. If $create is FALSE will return FALSE if there is no cart id.
 */
function uc_cart_get_id($create = TRUE) {
  global $user;

  if ($user->uid) {
    return $user->uid;
  }
  elseif (!isset($_SESSION['uc_cart_id']) && $create) {
    $_SESSION['uc_cart_id'] = md5(uniqid(rand(), TRUE));
  }

  return isset($_SESSION['uc_cart_id']) ? $_SESSION['uc_cart_id'] : FALSE;
}

/**
 * Grab the items in a shopping cart for a user.
 *
 * If $cid is not passed in, this function uses the uid of the person currently
 * accessing this function.
 */
function uc_cart_get_contents($cid = NULL, $action = NULL) {
  static $items = array();

  $cid = $cid ? $cid : uc_cart_get_id(FALSE);

  // If we didn't get a cid, return empty.
  if (!$cid) {
    return array();
  }

  if ($action == 'rebuild') {
    unset($items[$cid]);
  }

  if (!isset($items[$cid])) {
    $items[$cid] = array();
    $result = db_query("SELECT c.*, n.title, n.vid FROM {node} n INNER JOIN {uc_cart_products} c ON n.nid = c.nid WHERE c.cart_id = '%s'", $cid);

    while ($item = db_fetch_object($result)) {
      for ($i = 0; $i < count($items[$cid]); $i++) {
        if ($items[$cid][$i]->nid == $item->nid && $items[$cid][$i]->data == $item->data) {
          $items[$cid][$i]->qty += $item->qty;
          continue 2;
        }
      }
      $product = node_load($item->nid);
      $item->cost = $product->cost;
      $item->price = $product->sell_price;
      $item->weight = $product->weight;
      $item->data = unserialize($item->data);
      $item->module = $item->data['module'];
      $item->model = $product->model;

      // Invoke hook_cart_item() with $op = 'load' in enabled modules.
      foreach (module_list() as $module) {
        $func = $module .'_cart_item';
        if (function_exists($func)) {
          // $item must be passed by reference.
          $func('load', $item);
        }
      }

      $items[$cid][] = $item;
    }

    // Allow other modules a chance to alter the fully loaded cart object.
    drupal_alter('uc_cart', $items[$cid]);

    // When there are no longer any items in the cart, the anonymous cart ID is no longer required.
    // To guard against unsetting the session ID in the middle of an uc_cart_add_item() call, we only do this on rebuild
    // See issue 858816 for details.
    if ($action == 'rebuild' && empty($items[$cid]) && isset($_SESSION['uc_cart_id']) && $_SESSION['uc_cart_id'] == $cid) {
      unset($_SESSION['uc_cart_id']);
    }
  }

  return $items[$cid];
}

/**
 * Return the total number of items in the shopping cart.
 *
 * The total number of items in the cart isn't simply queried directly from the
 * database, because when the shopping cart is loaded items may in fact be
 * altered or removed. Hence we actually load the cart and tally up the total
 * number of items from the fully loaded cart instead.
 *
 * @param $cid
 *   The cart ID of the shopping cart whose items we're totalling; defaults to
 *     the current user's cart.
 * @return
 *   An integer representing the total number of items in the cart.
 */
function uc_cart_get_total_qty($cid = NULL) {

  $qty = 0;

  if (empty($cid)) {
    $cid = uc_cart_get_id(FALSE);
  }

  if ($cid) {
    foreach (uc_cart_get_contents($cid) as $item) {
      $qty += $item->qty;
    }
  }

  return $qty;
}

/**
 * Allow us to get one single line item in a cart
 *
 * @param $cart_item_id
 *   cart_item_id to fetch
 * @return
 *   Fully loaded cart item or NULL if item not found
 */
function uc_cart_get_item($cart_item_id) {
  $result = db_query("SELECT c.*, n.title, n.vid FROM {node} n INNER JOIN {uc_cart_products} c ON n.nid = c.nid WHERE c.cart_item_id = '%d'", $cart_item_id);
  $item = db_fetch_object($result);
  if (empty($item)) {
    return;
  }
  $product = node_load($item->nid);
  $item->cost = $product->cost;
  $item->price = $product->sell_price;
  $item->weight = $product->weight;
  $item->data = unserialize($item->data);
  $item->module = $item->data['module'];
  $item->model = $product->model;

  // Invoke hook_cart_item() with $op = 'load' in enabled modules.
  foreach (module_list() as $module) {
    $func = $module .'_cart_item';
    if (function_exists($func)) {
      // $item must be passed by reference.
      $func('load', $item);
    }
  }

  return $item;
}

/**
 * Update a cart item.
 *
 * @param $item
 *   The loaded cart item.
 * @return unknown_type
 */
function uc_cart_update_item($item) {
  db_query("UPDATE {uc_cart_products} SET qty = %d, changed = UNIX_TIMESTAMP(), data = '%s' WHERE cart_item_id = %d",
    $item->qty, serialize($item->data), $item->cart_item_id);
}

/**
 * Add an item to a user's cart.
 */
function uc_cart_add_item($nid, $qty = 1, $data = NULL, $cid = NULL, $msg = TRUE, $check_redirect = TRUE, $rebuild = TRUE) {
  if (isset($_SESSION['cart_order'])) {
    unset($_SESSION['cart_order']);
  }

  $cid = $cid ? $cid : uc_cart_get_id();
  $node = node_load($nid);

  if (is_null($data)) {
    $data = array('module' => 'uc_product');
  }
  if (!isset($data['module'])) {
    $data['module'] = 'uc_product';
  }

  if (!uc_product_is_product($node->type)) {
    drupal_set_message(t('@title is not a product. Unable to add to cart.', array('@title' => $node->title)), 'error');
    return;
  }

  $result = module_invoke_all('add_to_cart', $nid, $qty, $data);
  if (is_array($result) && !empty($result)) {
    foreach ($result as $row) {
      if ($row['success'] === FALSE) {
        if (isset($row['message']) && !empty($row['message'])) {
          $message = $row['message'];
        }
        else {
          $message = t('Sorry, that item is not available for purchase at this time.');
        }
        if ($row['silent'] === TRUE) {
          if ($check_redirect) {
            if (isset($_GET['destination'])) {
              drupal_goto();
            }
            $redirect = variable_get('uc_add_item_redirect', 'cart');
            if ($redirect != '<none>') {
              $_SESSION['uc_cart_last_url'] = uc_referer_uri();
              return $redirect;
            }
            else {
              return uc_referer_uri();
            }
          }
        }
        else {
          drupal_set_message($message, 'error');
        }
        return;
      }
    }
  }

  $item = db_fetch_object(db_query("SELECT * FROM {uc_cart_products} WHERE cart_id = '%s' AND nid = %d AND data = '%s'", $cid, $node->nid, serialize($data)));

  // If the item isn't in the cart yet, add it.
  if (is_null($item) || $item === FALSE) {
    db_query("INSERT INTO {uc_cart_products} (cart_id, nid, qty, changed, data) VALUES ('%s', %d, %d, %d, '%s')", $cid, $node->nid, $qty, time(), serialize($data));
    if ($msg) {
      drupal_set_message(t('<strong>@product-title</strong> added to <a href="!url">your shopping cart</a>.', array('@product-title' => $node->title, '!url' => url('cart'))));
    }
  }
  else {
    // Update the item instead.
    if ($msg) {
      drupal_set_message(t('Your item(s) have been updated.'));
    }
    $qty += $item->qty;
    module_invoke($data['module'], 'update_cart_item', $node->nid, $data, min($qty, 999999), $cid);
  }

  // If specified, rebuild the cached cart items array.
  if ($rebuild) {
    uc_cart_get_contents($cid, 'rebuild');
  }

  if ($check_redirect) {
    if (isset($_GET['destination'])) {
      drupal_goto();
    }

    $redirect = variable_get('uc_add_item_redirect', 'cart');
    if ($redirect != '<none>') {
      $_SESSION['uc_cart_last_url'] = uc_referer_uri();
      return $redirect;
    }
    else {
      return uc_referer_uri();
    }
  }
}

/**
 * Remove an item from the cart
 */
function uc_cart_remove_item($nid, $cid = NULL, $data = array()) {
  if (empty($nid)) {
    return;
  }

  $cart_id = !(is_null($cid) || empty($cid)) ? $cid : uc_cart_get_id();

  // Invoke hook_cart_item() with $op = 'remove' in enabled modules.
  $result = db_query("SELECT c.*, n.title, n.vid FROM {node} n INNER JOIN {uc_cart_products} c ON n.nid = c.nid WHERE c.cart_id = '%s' AND c.nid = %d", $cart_id, $nid);
  if ($item = db_fetch_object($result)) {
    foreach (module_list() as $module) {
      $func = $module .'_cart_item';
      if (function_exists($func)) {
        // $item must be passed by reference.
        $func('remove', $item);
      }
    }
  }

  db_query("DELETE FROM {uc_cart_products} WHERE cart_id = '%s' AND nid = %d AND data = '%s'", $cart_id, $nid, serialize($data));
}

/**
 * Update the quantity of all the items in a cart object
 */
function uc_cart_update_item_object($cart) {
  if (is_object($cart)) {
    foreach ($cart->items as $item) {
      if ($item['remove']) {
        module_invoke($item['module'], 'update_cart_item', $item['nid'], unserialize($item['data']), 0);
      }
      else {
        module_invoke($item['module'], 'update_cart_item', $item['nid'], unserialize($item['data']), $item['qty']);
      }
    }

    // Rebuild the cached cart items.
    uc_cart_get_contents(NULL, 'rebuild');
  }
}

/**
 * Empty a cart of its contents.
 */
function uc_cart_empty($cart_id) {
  if (is_null($cart_id) || empty($cart_id)) {
    return;
  }

  // Empty cart one item at a time.  This will ensure the cart_item hook is fired with $op set to 'remove' for each item.
  $items = uc_cart_get_contents($cart_id);
  foreach($items as $item) {
    uc_cart_remove_item($item->nid, $cart_id, $item->data);
  }

  // Probably don't need this query, but it will ensure anything not removed with the above loop is removed here.
  db_query("DELETE FROM {uc_cart_products} WHERE cart_id = '%s'", $cart_id);

  // Remove cached cart.
  uc_cart_get_contents($cart_id, 'rebuild');
}

/**
 * Get all of the enabled, sorted cart panes.
 *
 * @param $items
 *   The contents of the cart.
 * @param $action
 *   If 'rebuild' is passed, the static pane cache is cleared.
 */
function uc_cart_cart_pane_list($items, $action = NULL) {
  static $panes;

  if (count($panes) > 0 && $action !== 'rebuild') {
    return $panes;
  }

  $panes = module_invoke_all('cart_pane', $items);

  // Allow other modules to alter the panes.
  drupal_alter('cart_pane', $panes, $items);

  if (!is_array($panes) || count($panes) == 0) {
    return array();
  }
  foreach ($panes as $i => $value) {
    $panes[$i]['enabled'] = variable_get('uc_cap_'. $panes[$i]['id'] .'_enabled', (!isset($panes[$i]['enabled']) ? TRUE : $panes[$i]['enabled']));
    $panes[$i]['weight'] = variable_get('uc_cap_'. $panes[$i]['id'] .'_weight', (!isset($panes[$i]['weight']) ? 0 : $panes[$i]['weight']));
  }
  usort($panes, 'uc_weight_sort');

  return $panes;
}

/**
 * Determine whether a cart contains shippable items or not.
 */
function uc_cart_is_shippable($cart_id = NULL, $action = '') {
  static $shippable;

  if ($action != 'refresh' && ($shippable === FALSE || $shippable === TRUE)) {
    return $shippable;
  }

  $shippable = FALSE;
  $items = uc_cart_get_contents($cart_id);

  // Return FALSE if the cart is empty!
  if (empty($items)) {
    return FALSE;
  }

  foreach ($items as $item) {
    $result[] = uc_cart_product_is_shippable($item);
  }

  // Return TRUE if any product in the cart is shippable.
  if (in_array(TRUE, $result)) {
    $shippable = TRUE;
    return TRUE;
  }

  return FALSE;
}

/**
 * Determine whether a product is shippable or not.
 */
function uc_cart_product_is_shippable($product) {
  // Return FALSE if the product form specifies this as not shippable.
  if ($product->data['shippable'] == FALSE) {
    return FALSE;
  }

  $result = array();

  // See if any other modules have a say in the matter...
  foreach (module_list() as $module) {
    $func = $module .'_cart_item';
    if (function_exists($func)) {
      // $product must be passed by reference.
      $return = $func('can_ship', $product);

      if (!is_null($return)) {
        $result[] = $return;
      }
    }
  }

  // Return TRUE by default.
  if (empty($result) || in_array(TRUE, $result)) {
    return TRUE;
  }

  return FALSE;
}

/**
 * Remove panes from the list that match the given conditions.
 *
 * Return a checkout pane array with panes filtered out that have key values
 * matching the combinations in the $remove array.
 */
function uc_cart_filter_checkout_panes($panes, $remove = NULL) {
  if (is_array($remove)) {
    for ($i = 0, $j = count($panes); $i < $j; $i++) {
      foreach ($remove as $key => $value) {
        if ($panes[$i][$key] == $value) {
          unset($panes[$i]);
        }
      }
    }
  }

  return $panes;
}