<?php
// $Id: uc_attribute.module,v 1.12.2.38 2010/01/27 22:23:31 islandusurper Exp $

/**
 * @file
 * Ubercart Attribute module.
 *
 * Allows customers to buy slightly different products from the same listing.
 *
 * Many manufacturers provide options to their products. This module provides a way
 * for store administrators to consolidate these options into one product instead of
 * listing each combination separately. This is accomplished through the use of Drupal's
 * hook system.
 */

require_once('uc_attribute.ca.inc');

/******************************************************************************
 * Drupal Hooks                                                               *
 ******************************************************************************/

/**
 * Implementation of hook_help().
 */
function uc_attribute_help($path, $arg) {
  switch ($path) {
    // Help messages for the attributes overview on products and classes.
    case 'node/%/edit/attributes':
      return t('Add attributes to this product using the <a href="!url">add attributes form</a>. You may then adjust the settings for these attributes on this page and go on to configure their options in the <em>Options</em> tab.', array('!url' => url('node/'. $arg[1] .'/edit/attributes/add')));
    case 'admin/store/products/classes/%/attributes':
      return t('Add attributes to the product class using the <a href="!url">add attributes form</a>. You may then adjust the settings for these attributes on this page and go on to configure their options in the <em>Options</em> tab.', array('!url' => url('admin/store/products/classes/'. $arg[4] .'/attributes/add')));

    // Help message for adding an attribute to a product or class.
    case 'node/%/edit/attributes/add':
    case 'admin/store/products/classes/%/attributes/add':
      return t('Select the attributes you want to add and submit the form.');

    // Help message for adjusting the options on a product or class.
    case 'node/%/edit/options':
    case 'admin/store/products/classes/%/options':
      return t('Use the checkboxes to enable options for attributes and the radio buttons to specify defaults for the enabled options. Use the other fields to override the default settings for each option. Attributes with no enabled options will be displayed as text fields.');

    // Help message for the product Adjustments tab.
    case 'node/%/edit/adjustments':
      return t('Enter an alternate SKU to be used when the specified set of options are chosen and the product is added to the cart. <b>Warning:</b> Adding or removing attributes from this product will reset all the SKUs on this page to the default product SKU.');
  }
}

/**
 * Implementation of hook_menu().
 */
function uc_attribute_menu() {
  $items['admin/store/attributes'] = array(
    'title' => 'Attributes',
    'description' => 'Create and edit attributes and options.',
    'page callback' => 'uc_attribute_admin',
    'access arguments' => array('administer attributes'),
    'type' => MENU_NORMAL_ITEM,
    'weight' => -1,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['admin/store/attributes/overview'] = array(
    'title' => 'Overview',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => 0,
  );
  $items['admin/store/attributes/add'] = array(
    'title' => 'Add an attribute',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_attribute_form'),
    'access arguments' => array('administer attributes'),
    'type' => MENU_LOCAL_TASK,
    'weight' => 5,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['admin/store/settings/attributes'] = array(
    'title' => 'Attribute settings',
    'description' => 'Configure the attribute settings',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_attribute_admin_settings'),
    'access arguments' => array('administer attributes'),
    'type' => MENU_NORMAL_ITEM,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['admin/store/attributes/%uc_attribute/edit'] = array(
    'title' => 'Edit attribute',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_attribute_form', 3),
    'access arguments' => array('administer attributes'),
    'type' => MENU_CALLBACK,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['admin/store/attributes/%uc_attribute/delete'] = array(
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_attribute_delete_confirm', 3),
    'access arguments' => array('administer attributes'),
    'type' => MENU_CALLBACK,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['admin/store/attributes/%uc_attribute/options'] = array(
    'title' => 'Options',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_attribute_options_form', 3),
    'access arguments' => array('administer attributes'),
    'type' => MENU_CALLBACK,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['admin/store/attributes/%uc_attribute/options/overview'] = array(
    'title' => 'Overview',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => 0,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['admin/store/attributes/%uc_attribute/options/add'] = array(
    'title' => 'Add an option',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_attribute_option_form', 3, NULL),
    'access arguments' => array('administer attributes'),
    'type' => MENU_LOCAL_TASK,
    'weight' => 5,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['admin/store/attributes/%uc_attribute/options/%uc_attribute_option/edit'] = array(
    'title' => 'Edit option',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_attribute_option_form', 3, 5),
    'access arguments' => array('administer attributes'),
    'type' => MENU_CALLBACK,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['admin/store/attributes/%uc_attribute/options/%uc_attribute_option/delete'] = array(
    'title' => 'Delete option',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_attribute_option_delete_confirm', 3, 5),
    'access arguments' => array('administer attributes'),
    'type' => MENU_CALLBACK,
    'file' => 'uc_attribute.admin.inc',
  );

  // Menu items for default product class attributes and options.
  $items['admin/store/products/classes/%uc_product_class/attributes'] = array(
    'title' => 'Attributes',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_object_attributes_form', 4, 'class'),
    'access callback' => 'uc_attribute_product_class_access',
    'type' => MENU_LOCAL_TASK,
    'weight' => 1,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['admin/store/products/classes/%uc_product_class/options'] = array(
    'title' => 'Options',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_object_options_form', 4, 'class'),
    'access callback' => 'uc_attribute_product_class_access',
    'type' => MENU_LOCAL_TASK,
    'weight' => 2,
    'file' => 'uc_attribute.admin.inc',
  );

  // Insert subitems into the edit node page for product types.
  $items['node/%node/edit/attributes'] = array(
    'title' => 'Attributes',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_object_attributes_form', 1, 'product', 'overview'),
    'access callback' => 'uc_attribute_product_access',
    'access arguments' => array(1),
    'type' => MENU_LOCAL_TASK,
    'weight' => 1,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['node/%node/edit/attributes/add'] = array(
    'title' => 'Attributes',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_object_attributes_form', 1, 'product', 'add'),
    'access callback' => 'uc_attribute_product_access',
    'access arguments' => array(1),
    'type' => MENU_LOCAL_TASK,
    'weight' => 1,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['node/%node/edit/options'] = array(
    'title' => 'Options',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_object_options_form', 1, 'product'),
    'access callback' => 'uc_attribute_product_option_access',
    'access arguments' => array(1),
    'type' => MENU_LOCAL_TASK,
    'weight' => 2,
    'file' => 'uc_attribute.admin.inc',
  );
  $items['node/%node/edit/adjustments'] = array(
    'title' => 'Adjustments',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('uc_product_adjustments_form', 1),
    'access callback' => 'uc_attribute_product_option_access',
    'access arguments' => array(1),
    'type' => MENU_LOCAL_TASK,
    'weight' => 3,
    'file' => 'uc_attribute.admin.inc',
  );

  return $items;
}

/**
 * Access callback for editing a product class's attributes and options.
 */
function uc_attribute_product_class_access() {
  return user_access('administer product classes') && user_access('administer attributes');
}

/**
 * Access callback for editing a product's attributes.
 */
function uc_attribute_product_access($node) {
  if ($node->type == 'product_kit') {
    return FALSE;
  }

  return uc_product_is_product($node) && node_access('update', $node) && (user_access('administer attributes') || user_access('administer product attributes'));
}

/**
 * Access callback for editing a product's options.
 */
function uc_attribute_product_option_access($node) {
  if ($node->type == 'product_kit') {
    return FALSE;
  }

  return uc_product_is_product($node) && node_access('update', $node) && (user_access('administer attributes') || user_access('administer product attributes') || user_access('administer product options'));
}

/**
 * Implementation of hook_perm().
 */
function uc_attribute_perm() {
  return array('administer attributes', 'administer product attributes', 'administer product options');
}

/**
 * Implementation of hook_init().
 */
function uc_attribute_init() {
  drupal_add_css(drupal_get_path('module', 'uc_attribute') .'/uc_attribute.css');
}

/**
 * Implementation of hook_theme().
 */
function uc_attribute_theme() {
  return array(
    'uc_attribute_add_to_cart' => array(
      'arguments' => array('form' => NULL),
    ),
    'uc_object_attributes_form' => array(
      'arguments' => array('form' => NULL),
      'file' => 'uc_attribute.admin.inc',
    ),
    'uc_object_options_form' => array(
      'arguments' => array('form' => NULL),
      'file' => 'uc_attribute.admin.inc',
    ),
    'uc_attribute_options_form' => array(
      'arguments' => array('form' => NULL),
      'file' => 'uc_attribute.admin.inc',
    ),
    'uc_product_attributes' => array(
      'arguments' => array('product' => NULL),
      'file' => 'uc_attribute.admin.inc',
    ),
  );
}

/**
 * Implementation of hook_form_alter().
 */
function uc_attribute_form_alter(&$form, $form_state, $form_id) {
  if (strpos($form_id, 'add_product_form')) {
    $node =& $form['node']['#value'];
    // If the node has a product list, add attributes to them
    if (isset($form['sub_products']) && count(element_children($form['sub_products']))) {
      foreach (element_children($form['sub_products']) as $key) {
        $form['sub_products'][$key]['attributes'] = _uc_attribute_alter_form(node_load($key));
        if (is_array($form['sub_products'][$key]['attributes'])) {
          $form['sub_products'][$key]['attributes']['#tree'] = TRUE;
          $form['sub_products'][$key]['#type'] = 'fieldset';
        }
      }
    }
    // If not, add attributes to the node.
    else {
      $form['attributes'] = _uc_attribute_alter_form($node);

      if (is_array($form['attributes'])) {
        $form['attributes']['#tree'] = TRUE;
        $form['attributes']['#weight'] = -1;
      }
    }
  }
}

/**
 * Implementation of hook_uc_form_alter().
 *
 * Attach option selectors to the form with the "Add to Cart" button.
 *
 * This function also handles selecting attributes for products added to orders
 * manually.
 */
function uc_attribute_uc_form_alter(&$form, &$form_state, $form_id) {
  if (strpos($form_id, 'add_to_cart_form') || strpos($form_id, 'add_product_form')) {
    $node =& $form['node']['#value'];
    // If the node has a product list, add attributes to them
    if (isset($form['products']) && count(element_children($form['products']))) {
      foreach (element_children($form['products']) as $key) {
        $form['products'][$key]['attributes'] = _uc_attribute_alter_form(node_load($key));
        if (is_array($form['products'][$key]['attributes'])) {
          $form['products'][$key]['attributes']['#tree'] = TRUE;
          $form['products'][$key]['#type'] = 'fieldset';
        }
      }
    }
    // If not, add attributes to the node.
    else {
      $form['attributes'] = _uc_attribute_alter_form($node);

      if (is_array($form['attributes'])) {
        $form['attributes']['#tree'] = TRUE;
        $form['attributes']['#weight'] = -1;
      }
    }
  }
}

/**
 * Implementation of hook_nodeapi().
 */
function uc_attribute_nodeapi(&$node, $op, $arg3 = NULL, $arg4 = NULL) {
  if (uc_product_is_product($node->type)) {
    switch ($op) {
      case 'load':
        $attributes = uc_product_get_attributes($node->nid);
        if (is_array($attributes) && !empty($attributes)) {
          $node->attributes = $attributes;
          return array('attributes' => $attributes);
        }
        break;
      case 'insert':
        switch ($GLOBALS['db_type']) {
          case 'mysqli':
          case 'mysql':
            db_query("INSERT IGNORE INTO {uc_product_attributes} (nid, aid, label, ordering, required, display, default_option) SELECT %d, aid, label, ordering, required, display, default_option FROM {uc_class_attributes} WHERE pcid = '%s'", $node->nid, $node->type);
            db_query("INSERT IGNORE INTO {uc_product_options} (nid, oid, cost, price, weight, ordering) SELECT %d, oid, cost, price, weight, ordering FROM {uc_class_attribute_options} WHERE pcid = '%s'", $node->nid, $node->type);
            break;
          case 'pgsql':
            db_query("INSERT INTO {uc_product_attributes} (nid, aid, label, ordering, required, display, default_option) SELECT %d, aid, label, ordering, required, display, default_option FROM {uc_class_attributes} WHERE pcid = '%s'", $node->nid, $node->type);
            db_query("INSERT INTO {uc_product_options} (nid, oid, cost, price, weight, ordering) SELECT %d, oid, cost, price, weight, ordering FROM {uc_class_attribute_options} WHERE pcid = '%s'", $node->nid, $node->type);
            break;
        }

        break;
      case 'delete':
        db_query("DELETE FROM {uc_product_options} WHERE nid = %d", $node->nid);
        db_query("DELETE FROM {uc_product_adjustments} WHERE nid = %d", $node->nid);
        db_query("DELETE FROM {uc_product_attributes} WHERE nid = %d", $node->nid);
        break;
      case 'update index':
        $output = '';
        $attributes = uc_product_get_attributes($node->nid);
        foreach ($attributes as $attribute) {
          $output .= '<h3>'. _uc_attribute_get_name($attribute) .'</h3>';
          foreach ($attribute->options as $option) {
            $output .= $option->name .' ';
          }
          $output .= "\n";
        }
        $result = db_query("SELECT model FROM {uc_product_adjustments} WHERE nid = %d", $node->nid);
        while ($adjustment = db_fetch_object($result)) {
          $output .= '<h2>'. $adjustment->model ."</h2>\n";
        }
        return $output;
    }
  }
}

/******************************************************************************
 * Ubercart Hooks                                                             *
 ******************************************************************************/

/**
 * Implementation of hook_uc_product_models().
 */
function uc_attribute_uc_product_models($node) {
  $models = array();

  // Get all the SKUs for all the attributes on this node.
  $adjustments = db_query("SELECT model FROM {uc_product_adjustments} WHERE nid = %d", $node->nid);
  while ($adjustment = db_fetch_object($adjustments)) {
    if (!in_array($adjustment->model, $models)) {
      $models[] = $adjustment->model;
    }
  }

  return $models;
}

/**
 * Store the customer's choices in the cart.
 */
function uc_attribute_add_to_cart_data($form_values) {
  if (isset($form_values['attributes'])) {
    return array('attributes' => $form_values['attributes']);
  }
  else {
    return array('attributes' => array());
  }
}

/**
 * Implemenation of hook_order_product_alter().
 */
function uc_attribute_order_product_alter(&$product, $order) {
  // Convert the attribute and option ids to their current names. This
  // preserves the important data in case the attributes or options are
  // changed later.
  if (is_array($product->data['attributes']) && is_numeric(key($product->data['attributes']))) {
    $attributes = array();
    $options = _uc_cart_product_get_options($product);
    foreach ($options as $aid => $option) {
      $attributes[$option['attribute']][] = $option['name'];
    }
    $product->data['attributes'] = $attributes;
  }
}

/**
 * Implementation of hook_product_class().
 */
function uc_attribute_product_class($type, $op) {
  switch ($op) {
    case 'delete':
      db_query("DELETE FROM {uc_class_attributes} WHERE pcid = '%s'", $type);
      db_query("DELETE FROM {uc_class_attribute_options} WHERE pcid = '%s'", $type);
    break;
  }
}

/**
 * Implementation of hook_cart_item().
 */
function uc_attribute_cart_item($op, &$item) {
  switch ($op) {
    case 'load':
      $options = _uc_cart_product_get_options($item);

      $op_costs = 0;
      $op_prices = 0;
      $op_weight = 0;

      foreach ($options as $option) {
        $op_costs += $option['cost'];
        $op_prices += $option['price'];
        $op_weight += $option['weight'];
      }
      $item->cost += $op_costs;
      $item->price += $op_prices;
      $item->weight += $op_weight;

      $combination = array();
      foreach ((array)$item->data['attributes'] as $aid => $value) {
        if (is_numeric($value)) {
          $attribute = uc_attribute_load($aid, $item->nid, 'product');
          if ($attribute && ($attribute->display == 1 || $attribute->display == 2)) {
            $combination[$aid] = $value;
          }
        }
      }
      ksort($combination);

      $result = db_query("SELECT model FROM {uc_product_adjustments} WHERE nid = %d AND combination LIKE '%s'", $item->nid, serialize($combination));
      $model = db_result($result);

      if (!empty($model)) {
        $item->model = $model;
      }
      break;
  }
}

/**
 * Implementation of hook_product_description().
 */
function uc_attribute_product_description($product) {
  $description = array(
    'attributes' => array(
      '#product' => array(
        '#type' => 'value',
        '#value' => $product,
      ),
      '#theme' => 'uc_product_attributes',
      '#weight' => 1,
    ),
  );

  $desc =& $description['attributes'];

  // Cart version of the product has numeric attribute => option values so we
  // need to retrieve the right ones
  $weight = 0;
  if (empty($product->order_id)) {
    foreach (_uc_cart_product_get_options($product) as $option) {
      if (!isset($desc[$option['aid']])) {
        $desc[$option['aid']]['#attribute_name'] = $option['attribute'];
        $desc[$option['aid']]['#options'] = array($option['name']);
      }
      else {
        $desc[$option['aid']]['#options'][] = $option['name'];
      }
      $desc[$option['aid']]['#weight'] = $weight++;
    }
  }
  else {
    foreach ((array)$product->data['attributes'] as $attribute => $option) {
      $desc[] = array(
        '#attribute_name' => $attribute,
        '#options' => $option,
        '#weight' => $weight++,
      );
    }
  }

  return $description;
}

/******************************************************************************
 * Module Functions                                                           *
 ******************************************************************************/

/**
 * Load an attribute from the database.
 *
 * @param $attr_id
 *   The id of the attribute.
 * @param $nid
 *   If given, the attribute will have the options that have been assigned to
 *   that $type for the attribute.
 * @param $type
 *   Determines whether $nid refers to a node or product class. $nid is ignored
 *   if $type is not 'product' or 'class'.
 * @return
 *   An attribute object with its options.
 */
function uc_attribute_load($attr_id, $nid = NULL, $type = '') {
  if ($nid) {
    switch ($type) {
      case 'product':
        $attribute = db_fetch_object(db_query("SELECT a.aid, a.name, a.label AS default_label, a.ordering AS default_ordering, a.required AS default_required, a.display AS default_display, a.description, pa.label, pa.default_option, pa.required, pa.ordering, pa.display FROM {uc_attributes} AS a LEFT JOIN {uc_product_attributes} AS pa ON a.aid = pa.aid AND pa.nid = %d WHERE a.aid = %d", $nid, $attr_id));
        $result = db_query("SELECT po.nid, po.oid, po.cost, po.price, po.weight, po.ordering, ao.name, ao.aid FROM {uc_product_options} AS po LEFT JOIN {uc_attribute_options} AS ao ON po.oid = ao.oid AND nid = %d WHERE aid = %d ORDER BY po.ordering, ao.name", $nid, $attr_id);
        break;
      case 'class':
        $attribute = db_fetch_object(db_query("SELECT a.aid, a.name, a.label AS default_label, a.ordering AS default_ordering, a.required AS default_required, a.display AS default_display, a.description, ca.default_option, ca.label, ca.required, ca.ordering, ca.display FROM {uc_attributes} AS a LEFT JOIN {uc_class_attributes} AS ca ON a.aid = ca.aid AND ca.pcid = '%s' WHERE a.aid = %d", $nid, $attr_id));
        $result = db_query("SELECT co.pcid, co.oid, co.cost, co.price, co.weight, co.ordering, ao.name, ao.aid FROM {uc_class_attribute_options} AS co LEFT JOIN {uc_attribute_options} AS ao ON co.oid = ao.oid AND co.pcid = '%s' WHERE ao.aid = %d ORDER BY co.ordering, ao.name", $nid, $attr_id);
        break;
      default:
        $attribute = db_fetch_object(db_query("SELECT * FROM {uc_attributes} WHERE aid = %d", $attr_id));
        $result = db_query("SELECT * FROM {uc_attribute_options} WHERE aid = %d ORDER BY ordering, name, label", $attr_id);
        break;
    }
    if (isset($attribute->default_ordering) && is_null($attribute->ordering)) {
      $attribute->ordering = $attribute->default_ordering;
    }
    if (isset($attribute->default_required) && is_null($attribute->required)) {
      $attribute->required = $attribute->default_required;
    }
    if (isset($attribute->default_display) && is_null($attribute->display)) {
      $attribute->display = $attribute->default_display;
    }
    if (isset($attribute->default_label) && is_null($attribute->label)) {
      $attribute->label = $attribute->default_label;
    }
    if (empty($attribute->label)) {
      $attribute->label = $attribute->name;
    }
  }
  else {
    $attribute = db_fetch_object(db_query("SELECT * FROM {uc_attributes} WHERE aid = %d", $attr_id));
    $result = db_query("SELECT * FROM {uc_attribute_options} WHERE aid = %d ORDER BY ordering, name", $attr_id);
  }
  if ($attribute) {
    $attribute->options = array();
    while ($option = db_fetch_object($result)) {
      $attribute->options[$option->oid] = $option;
    }
  }
  return $attribute;
}

/**
 * Load the option identified by $oid.
 */
function uc_attribute_option_load($oid) {
  return db_fetch_object(db_query("SELECT * FROM {uc_attribute_options} WHERE oid = %d", $oid));
}

/**
 * Load all attributes associated with a product node.
 */
function uc_product_get_attributes($nid) {
  $attributes = array();

  $result = db_query("SELECT upa.aid FROM {uc_product_attributes} AS upa LEFT JOIN {uc_attributes} AS ua ON upa.aid = ua.aid WHERE upa.nid = %d ORDER BY upa.ordering, ua.name", $nid);
  while ($attribute = db_fetch_object($result)) {
    $attributes[$attribute->aid] = uc_attribute_load($attribute->aid, $nid, 'product');
  }

  return $attributes;
}

/**
 * Load all attributes associated with a product class.
 */
function uc_class_get_attributes($pcid) {
  $attributes = array();

  $result = db_query("SELECT uca.aid FROM {uc_class_attributes} AS uca LEFT JOIN {uc_attributes} AS ua ON uca.aid = ua.aid WHERE uca.pcid = '%s' ORDER BY uca.ordering, ua.name", $pcid);
  while ($attribute = db_fetch_object($result)) {
    $attributes[$attribute->aid] = uc_attribute_load($attribute->aid, $pcid, 'class');
  }

  return $attributes;
}

/**
 * Get the options chosen for a product that is in the cart.
 *
 * @param $item
 *   An element of the array returned by uc_cart_get_contents.
 * @return
 *   Array of options chosen by a customer, indexed by attribute ids. Each
 *   element stores the attribute name and the option object chosen.
 */
function _uc_cart_product_get_options($item) {
  $options = array();
  $data = $item->data;
  $node = node_load($item->nid);

  $index = 0;
  if (!empty($data['attributes']) && is_array($data['attributes'])) {
    foreach ($data['attributes'] as $aid => $selected) {
      if (isset($node->attributes[$aid])) {
        $attribute = $node->attributes[$aid];
        $name = _uc_attribute_get_name($attribute);
        // Only discrete options can affect the price of an item.
        if ($attribute->display && count($attribute->options)) {
          // There may be many selected options, or just one.
          foreach ((array)$selected as $oid) {
            if ($oid > 0) {
              $options[$index] = (array)$attribute->options[$oid];
              $options[$index]['attribute'] = $name;
              $index++;
            }
          }
        }
        else {
          // Handle textfield attributes.
          $options[$index] = array(
            'attribute' => $name,
            'aid' => $aid,
            'oid' => 0,
            'name' => $selected,
            'cost' => 0,
            'price' => 0,
            'weight' => 0,
          );
        }
        $index++;
      }
    }
  }
  else {
    $options = array();
  }
  return $options;
}

/**
 * Helper function for uc_attribute_form_alter().
 *
 * @see theme_uc_attribute_add_to_cart()
 */
function _uc_attribute_alter_form($product) {
  // If the product doesn't have attributes, return the form as it is.
  if (!isset($product->attributes)) {
    $product->attributes = uc_product_get_attributes($product->nid);
  }
  if (!is_array($product->attributes) || empty($product->attributes)) {
    return NULL;
  }

  $nid = $product->nid;
  $qty = $product->default_qty;
  if (!$qty) {
    $qty = 1;
  }

  // Load all product attributes for the given nid.
  $priced_attributes = uc_attribute_priced_attributes($nid);
  $attributes = $product->attributes;

  $form_attributes = array();

  $context = array(
    'revision' => 'formatted',
  );

  // Loop through each product attribute and generate its form element.
  foreach ($attributes as $attribute) {
    $context['subject']['attribute'] = $attribute;
    // Build the attribute's options array.
    $options = array();
    foreach ($attribute->options as $option) {
      $context['subject']['option'] = $option;
      switch (variable_get('uc_attribute_option_price_format', 'adjustment')) {
        case 'total':
          $context['type'] = 'product';
          $context['subject']['node'] = $product;
          $price_info = array(
            'price' => $product->sell_price + $option->price,
            'qty' => $qty,
          );
          $display_price = in_array($attribute->aid, $priced_attributes) ? ', '. uc_price($price_info, $context) : '';
          if (count($priced_attributes) == 1 && $attribute->display != 3) {
            break;
          }
        case 'adjustment':
          $context['type'] = 'attribute_option';
          $price_info = array(
            'price' => $option->price,
            'qty' => $qty,
          );
          $display_price = ($option->price != 0 ? ', '. ($option->price > 0 ? '+' : '') . uc_price($price_info, $context) : '');
          break;
        case 'none':
        default:
          $display_price = '';
          break;
      }
      $options[$option->oid] = $option->name;
      if ($attribute->display == 2) {
        // Select options are check_plain()ed, but radio button labels are not.
        $options[$option->oid] = check_plain($options[$option->oid]);
      }
      $options[$option->oid] .= $display_price;
    }

    if (count($attribute->options) && $attribute->display > 0) {
      if ($attribute->required) {
        if ($attribute->display == 1) {
          $options = array('' => t('Please select')) + $options;
        }
        unset($attribute->default_option);
      }
      switch ($attribute->display) {
        case 1:
          $attr_type = 'select';
          break;
        case 2:
          $attr_type = 'radios';
          break;
        case 3:
          $attr_type = 'checkboxes';
          break;
      }
      $form_attributes[$attribute->aid] = array(
        '#type' => $attr_type,
        '#description' => check_markup($attribute->description),
        '#default_value' => ($attr_type == "checkboxes" ? array() : $attribute->default_option),
        '#options' => $options,
        '#required' => $attribute->required,
      );
    }
    else {
      $form_attributes[$attribute->aid] = array(
        '#type' => 'textfield',
        '#description' => check_markup($attribute->description),
        '#default_value' => $attribute->required == FALSE ? $attribute->options[$attribute->default_option]->name : '',
        '#required' => $attribute->required,
      );
    }

    $name = _uc_attribute_get_name($attribute, FALSE);
    if (!is_null($name)) {
      $form_attributes[$attribute->aid]['#title'] = check_plain($name);
    }

    $form_attributes['#theme'] = 'uc_attribute_add_to_cart';
  }
  return $form_attributes;
}

/**
 * Return an array of display types used as options when creating attributes.
 */
function _uc_attribute_display_types() {
  return array(
    0 => t('Text field'),
    1 => t('Select box'),
    2 => t('Radio buttons'),
    3 => t('Checkboxes'),
  );
}

/**
 * Get the price affecting attributes for a product
 *
 * @param $nid
 *   The nid of a product.
 * @return
 *   Array of attribute ids that have price affecting options.
 */
function uc_attribute_priced_attributes($nid) {
  $attributes = db_query("SELECT DISTINCT (pa.aid) FROM {uc_product_attributes} AS pa INNER JOIN {uc_attribute_options} AS ao ON ao.aid = pa.aid INNER JOIN {uc_product_options} AS po ON (po.oid = ao.oid AND po.nid = pa.nid) WHERE pa.nid = %d AND po.price <> 0 AND pa.display <> 0", $nid);
  $aids = array();
  while ($attribute = db_fetch_array($attributes)) {
    $aids[] = $attribute['aid'];
  }
  return $aids;
}

/**
 * Display the attribute selection form elements.
 *
 * @ingroup themeable
 * @see _uc_attribute_alter_form()
 */
function theme_uc_attribute_add_to_cart($form) {
  $output = '<div class="attributes">';
  $stripes = array('even' => 'odd', 'odd' => 'even');
  $parity = 'even';
  foreach (element_children($form) as $aid) {
    $parity = $stripes[$parity];
    $classes = array('attribute', 'attribute-'. $aid, $parity);
    $output .= '<div class="'. implode(' ', $classes) .'">';
    $output .= drupal_render($form[$aid]);
    $output .= '</div>';
  }

  $output .= drupal_render($form) .'</div>';

  return $output;
}

/**
 * Returns the attribute name to display.
 *
 * An attribute with a label set returns that label except when set to
 * '<none>'. In this case, a NULL is returned. The $title argument forces the
 * function to return the name property instead of label when label is set to
 * '<none>'.
 *
 * The NULL return value is typically used by forms so they know to hide the
 * #title property of the element.
 *
 * @param $attribute
 *   Attribute object
 * @param $title
 *   TRUE indicates the function is to return the attribute name when its label
 *   is set to '<none>'.
 * @return
 *   When the attribute label is set and not '<none>', it is returned.
 *   Otherwise, the attribute name is returned when $title is TRUE and NULL is
 *   returned when $title is FALSE.
 */
function _uc_attribute_get_name($attribute, $title = TRUE) {
  if (!$title && $attribute->label == '<none>') {
    return NULL;
  }
  else {
    return (empty($attribute->label) || ($attribute->label == '<none>' && $title) ? $attribute->name : $attribute->label);
  }
}
