system/libraries/Cart.php - code-igniter-v3-giggi - Gitiles

 <?php
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP
  *
  * This content is released under the MIT License (MIT)
  *
  * Copyright (c) 2014 - 2018, British Columbia Institute of Technology
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  *
  * @package	CodeIgniter
  * @author	EllisLab Dev Team
  * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
  * @copyright	Copyright (c) 2014 - 2018, British Columbia Institute of Technology (http://bcit.ca/)
  * @license	http://opensource.org/licenses/MIT	MIT License
  * @link	https://codeigniter.com
  * @since	Version 1.0.0
  * @filesource
  */
 defined('BASEPATH') OR exit('No direct script access allowed');

 /**
  * Shopping Cart Class
  *
  * @package		CodeIgniter
  * @subpackage	Libraries
  * @category	Shopping Cart
  * @author		EllisLab Dev Team
  * @link		https://codeigniter.com/user_guide/libraries/cart.html
  * @deprecated	3.0.0	This class is too specific for CI.
  */
 class CI_Cart {

 	/**
 	 * These are the regular expression rules that we use to validate the product ID and product name
 	 * alpha-numeric, dashes, underscores, or periods
 	 *
 	 * @var string
 	 */
 	public $product_id_rules = '\.a-z0-9_-';

 	/**
 	 * These are the regular expression rules that we use to validate the product ID and product name
 	 * alpha-numeric, dashes, underscores, colons or periods
 	 *
 	 * @var string
 	 */
 	public $product_name_rules = '\w \-\.\:';

 	/**
 	 * only allow safe product names
 	 *
 	 * @var bool
 	 */
 	public $product_name_safe = TRUE;

 	// --------------------------------------------------------------------------

 	/**
 	 * Reference to CodeIgniter instance
 	 *
 	 * @var object
 	 */
 	protected $CI;

 	/**
 	 * Contents of the cart
 	 *
 	 * @var array
 	 */
 	protected $_cart_contents = array();

 	/**
 	 * Shopping Class Constructor
 	 *
 	 * The constructor loads the Session class, used to store the shopping cart contents.
 	 *
 	 * @param	array
 	 * @return	void
 	 */
 	public function __construct($params = array())
 	{
 		// Set the super object to a local variable for use later
 		$this->CI =& get_instance();

 		// Are any config settings being passed manually?  If so, set them
 		$config = is_array($params) ? $params : array();

 		// Load the Sessions class
 		$this->CI->load->driver('session', $config);

 		// Grab the shopping cart array from the session table
 		$this->_cart_contents = $this->CI->session->userdata('cart_contents');
 		if ($this->_cart_contents === NULL)
 		{
 			// No cart exists so we'll set some base values
 			$this->_cart_contents = array('cart_total' => 0, 'total_items' => 0);
 		}

 		log_message('info', 'Cart Class Initialized');
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Insert items into the cart and save it to the session table
 	 *
 	 * @param	array
 	 * @return	bool
 	 */
 	public function insert($items = array())
 	{
 		// Was any cart data passed? No? Bah...
 		if ( ! is_array($items) OR count($items) === 0)
 		{
 			log_message('error', 'The insert method must be passed an array containing data.');
 			return FALSE;
 		}

 		// You can either insert a single product using a one-dimensional array,
 		// or multiple products using a multi-dimensional one. The way we
 		// determine the array type is by looking for a required array key named "id"
 		// at the top level. If it's not found, we will assume it's a multi-dimensional array.

 		$save_cart = FALSE;
 		if (isset($items['id']))
 		{
 			if (($rowid = $this->_insert($items)))
 			{
 				$save_cart = TRUE;
 			}
 		}
 		else
 		{
 			foreach ($items as $val)
 			{
 				if (is_array($val) && isset($val['id']))
 				{
 					if ($this->_insert($val))
 					{
 						$save_cart = TRUE;
 					}
 				}
 			}
 		}

 		// Save the cart data if the insert was successful
 		if ($save_cart === TRUE)
 		{
 			$this->_save_cart();
 			return isset($rowid) ? $rowid : TRUE;
 		}

 		return FALSE;
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Insert
 	 *
 	 * @param	array
 	 * @return	bool
 	 */
 	protected function _insert($items = array())
 	{
 		// Was any cart data passed? No? Bah...
 		if ( ! is_array($items) OR count($items) === 0)
 		{
 			log_message('error', 'The insert method must be passed an array containing data.');
 			return FALSE;
 		}

 		// --------------------------------------------------------------------

 		// Does the $items array contain an id, quantity, price, and name?  These are required
 		if ( ! isset($items['id'], $items['qty'], $items['price'], $items['name']))
 		{
 			log_message('error', 'The cart array must contain a product ID, quantity, price, and name.');
 			return FALSE;
 		}

 		// --------------------------------------------------------------------

 		// Prep the quantity. It can only be a number.  Duh... also trim any leading zeros
 		$items['qty'] = (float) $items['qty'];

 		// If the quantity is zero or blank there's nothing for us to do
 		if ($items['qty'] == 0)
 		{
 			return FALSE;
 		}

 		// --------------------------------------------------------------------

 		// Validate the product ID. It can only be alpha-numeric, dashes, underscores or periods
 		// Not totally sure we should impose this rule, but it seems prudent to standardize IDs.
 		// Note: These can be user-specified by setting the $this->product_id_rules variable.
 		if ( ! preg_match('/^['.$this->product_id_rules.']+$/i', $items['id']))
 		{
 			log_message('error', 'Invalid product ID.  The product ID can only contain alpha-numeric characters, dashes, and underscores');
 			return FALSE;
 		}

 		// --------------------------------------------------------------------

 		// Validate the product name. It can only be alpha-numeric, dashes, underscores, colons or periods.
 		// Note: These can be user-specified by setting the $this->product_name_rules variable.
 		if ($this->product_name_safe && ! preg_match('/^['.$this->product_name_rules.']+$/i'.(UTF8_ENABLED ? 'u' : ''), $items['name']))
 		{
 			log_message('error', 'An invalid name was submitted as the product name: '.$items['name'].' The name can only contain alpha-numeric characters, dashes, underscores, colons, and spaces');
 			return FALSE;
 		}

 		// --------------------------------------------------------------------

 		// Prep the price. Remove leading zeros and anything that isn't a number or decimal point.
 		$items['price'] = (float) $items['price'];

 		// We now need to create a unique identifier for the item being inserted into the cart.
 		// Every time something is added to the cart it is stored in the master cart array.
 		// Each row in the cart array, however, must have a unique index that identifies not only
 		// a particular product, but makes it possible to store identical products with different options.
 		// For example, what if someone buys two identical t-shirts (same product ID), but in
 		// different sizes?  The product ID (and other attributes, like the name) will be identical for
 		// both sizes because it's the same shirt. The only difference will be the size.
 		// Internally, we need to treat identical submissions, but with different options, as a unique product.
 		// Our solution is to convert the options array to a string and MD5 it along with the product ID.
 		// This becomes the unique "row ID"
 		if (isset($items['options']) && count($items['options']) > 0)
 		{
 			$rowid = md5($items['id'].serialize($items['options']));
 		}
 		else
 		{
 			// No options were submitted so we simply MD5 the product ID.
 			// Technically, we don't need to MD5 the ID in this case, but it makes
 			// sense to standardize the format of array indexes for both conditions
 			$rowid = md5($items['id']);
 		}

 		// --------------------------------------------------------------------

 		// Now that we have our unique "row ID", we'll add our cart items to the master array
 		// grab quantity if it's already there and add it on
 		$old_quantity = isset($this->_cart_contents[$rowid]['qty']) ? (int) $this->_cart_contents[$rowid]['qty'] : 0;

 		// Re-create the entry, just to make sure our index contains only the data from this submission
 		$items['rowid'] = $rowid;
 		$items['qty'] += $old_quantity;
 		$this->_cart_contents[$rowid] = $items;

 		return $rowid;
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Update the cart
 	 *
 	 * This function permits the quantity of a given item to be changed.
 	 * Typically it is called from the "view cart" page if a user makes
 	 * changes to the quantity before checkout. That array must contain the
 	 * product ID and quantity for each item.
 	 *
 	 * @param	array
 	 * @return	bool
 	 */
 	public function update($items = array())
 	{
 		// Was any cart data passed?
 		if ( ! is_array($items) OR count($items) === 0)
 		{
 			return FALSE;
 		}

 		// You can either update a single product using a one-dimensional array,
 		// or multiple products using a multi-dimensional one.  The way we
 		// determine the array type is by looking for a required array key named "rowid".
 		// If it's not found we assume it's a multi-dimensional array
 		$save_cart = FALSE;
 		if (isset($items['rowid']))
 		{
 			if ($this->_update($items) === TRUE)
 			{
 				$save_cart = TRUE;
 			}
 		}
 		else
 		{
 			foreach ($items as $val)
 			{
 				if (is_array($val) && isset($val['rowid']))
 				{
 					if ($this->_update($val) === TRUE)
 					{
 						$save_cart = TRUE;
 					}
 				}
 			}
 		}

 		// Save the cart data if the insert was successful
 		if ($save_cart === TRUE)
 		{
 			$this->_save_cart();
 			return TRUE;
 		}

 		return FALSE;
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Update the cart
 	 *
 	 * This function permits changing item properties.
 	 * Typically it is called from the "view cart" page if a user makes
 	 * changes to the quantity before checkout. That array must contain the
 	 * rowid and quantity for each item.
 	 *
 	 * @param	array
 	 * @return	bool
 	 */
 	protected function _update($items = array())
 	{
 		// Without these array indexes there is nothing we can do
 		if ( ! isset($items['rowid'], $this->_cart_contents[$items['rowid']]))
 		{
 			return FALSE;
 		}

 		// Prep the quantity
 		if (isset($items['qty']))
 		{
 			$items['qty'] = (float) $items['qty'];
 			// Is the quantity zero?  If so we will remove the item from the cart.
 			// If the quantity is greater than zero we are updating
 			if ($items['qty'] == 0)
 			{
 				unset($this->_cart_contents[$items['rowid']]);
 				return TRUE;
 			}
 		}

 		// find updatable keys
 		$keys = array_intersect(array_keys($this->_cart_contents[$items['rowid']]), array_keys($items));
 		// if a price was passed, make sure it contains valid data
 		if (isset($items['price']))
 		{
 			$items['price'] = (float) $items['price'];
 		}

 		// product id & name shouldn't be changed
 		foreach (array_diff($keys, array('id', 'name')) as $key)
 		{
 			$this->_cart_contents[$items['rowid']][$key] = $items[$key];
 		}

 		return TRUE;
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Save the cart array to the session DB
 	 *
 	 * @return	bool
 	 */
 	protected function _save_cart()
 	{
 		// Let's add up the individual prices and set the cart sub-total
 		$this->_cart_contents['total_items'] = $this->_cart_contents['cart_total'] = 0;
 		foreach ($this->_cart_contents as $key => $val)
 		{
 			// We make sure the array contains the proper indexes
 			if ( ! is_array($val) OR ! isset($val['price'], $val['qty']))
 			{
 				continue;
 			}

 			$this->_cart_contents['cart_total'] += ($val['price'] * $val['qty']);
 			$this->_cart_contents['total_items'] += $val['qty'];
 			$this->_cart_contents[$key]['subtotal'] = ($this->_cart_contents[$key]['price'] * $this->_cart_contents[$key]['qty']);
 		}

 		// Is our cart empty? If so we delete it from the session
 		if (count($this->_cart_contents) <= 2)
 		{
 			$this->CI->session->unset_userdata('cart_contents');

 			// Nothing more to do... coffee time!
 			return FALSE;
 		}

 		// If we made it this far it means that our cart has data.
 		// Let's pass it to the Session class so it can be stored
 		$this->CI->session->set_userdata(array('cart_contents' => $this->_cart_contents));

 		// Woot!
 		return TRUE;
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Cart Total
 	 *
 	 * @return	int
 	 */
 	public function total()
 	{
 		return $this->_cart_contents['cart_total'];
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Remove Item
 	 *
 	 * Removes an item from the cart
 	 *
 	 * @param	int
 	 * @return	bool
 	 */
 	 public function remove($rowid)
 	 {
 		// unset & save
 		unset($this->_cart_contents[$rowid]);
 		$this->_save_cart();
 		return TRUE;
 	 }

 	// --------------------------------------------------------------------

 	/**
 	 * Total Items
 	 *
 	 * Returns the total item count
 	 *
 	 * @return	int
 	 */
 	public function total_items()
 	{
 		return $this->_cart_contents['total_items'];
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Cart Contents
 	 *
 	 * Returns the entire cart array
 	 *
 	 * @param	bool
 	 * @return	array
 	 */
 	public function contents($newest_first = FALSE)
 	{
 		// do we want the newest first?
 		$cart = ($newest_first) ? array_reverse($this->_cart_contents) : $this->_cart_contents;

 		// Remove these so they don't create a problem when showing the cart table
 		unset($cart['total_items']);
 		unset($cart['cart_total']);

 		return $cart;
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Get cart item
 	 *
 	 * Returns the details of a specific item in the cart
 	 *
 	 * @param	string	$row_id
 	 * @return	array
 	 */
 	public function get_item($row_id)
 	{
 		return (in_array($row_id, array('total_items', 'cart_total'), TRUE) OR ! isset($this->_cart_contents[$row_id]))
 			? FALSE
 			: $this->_cart_contents[$row_id];
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Has options
 	 *
 	 * Returns TRUE if the rowid passed to this function correlates to an item
 	 * that has options associated with it.
 	 *
 	 * @param	string	$row_id = ''
 	 * @return	bool
 	 */
 	public function has_options($row_id = '')
 	{
 		return (isset($this->_cart_contents[$row_id]['options']) && count($this->_cart_contents[$row_id]['options']) !== 0);
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Product options
 	 *
 	 * Returns the an array of options, for a particular product row ID
 	 *
 	 * @param	string	$row_id = ''
 	 * @return	array
 	 */
 	public function product_options($row_id = '')
 	{
 		return isset($this->_cart_contents[$row_id]['options']) ? $this->_cart_contents[$row_id]['options'] : array();
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Format Number
 	 *
 	 * Returns the supplied number with commas and a decimal point.
 	 *
 	 * @param	float
 	 * @return	string
 	 */
 	public function format_number($n = '')
 	{
 		return ($n === '') ? '' : number_format( (float) $n, 2, '.', ',');
 	}

 	// --------------------------------------------------------------------

 	/**
 	 * Destroy the cart
 	 *
 	 * Empties the cart and kills the session
 	 *
 	 * @return	void
 	 */
 	public function destroy()
 	{
 		$this->_cart_contents = array('cart_total' => 0, 'total_items' => 0);
 		$this->CI->session->unset_userdata('cart_contents');
 	}

 }
	<?php
	/**
	* CodeIgniter
	*
	* An open source application development framework for PHP
	*
	* This content is released under the MIT License (MIT)
	*
	* Copyright (c) 2014 - 2018, British Columbia Institute of Technology
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	* THE SOFTWARE.
	*
	* @package CodeIgniter
	* @author EllisLab Dev Team
	* @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
	* @copyright Copyright (c) 2014 - 2018, British Columbia Institute of Technology (http://bcit.ca/)
	* @license http://opensource.org/licenses/MIT MIT License
	* @link https://codeigniter.com
	* @since Version 1.0.0
	* @filesource
	*/
	defined('BASEPATH') OR exit('No direct script access allowed');

	/**
	* Shopping Cart Class
	*
	* @package CodeIgniter
	* @subpackage Libraries
	* @category Shopping Cart
	* @author EllisLab Dev Team
	* @link https://codeigniter.com/user_guide/libraries/cart.html
	* @deprecated 3.0.0 This class is too specific for CI.
	*/
	class CI_Cart {

	/**
	* These are the regular expression rules that we use to validate the product ID and product name
	* alpha-numeric, dashes, underscores, or periods
	*
	* @var string
	*/
	public $product_id_rules = '\.a-z0-9_-';

	/**
	* These are the regular expression rules that we use to validate the product ID and product name
	* alpha-numeric, dashes, underscores, colons or periods
	*
	* @var string
	*/
	public $product_name_rules = '\w \-\.\:';

	/**
	* only allow safe product names
	*
	* @var bool
	*/
	public $product_name_safe = TRUE;

	// --------------------------------------------------------------------------

	/**
	* Reference to CodeIgniter instance
	*
	* @var object
	*/
	protected $CI;

	/**
	* Contents of the cart
	*
	* @var array
	*/
	protected $_cart_contents = array();

	/**
	* Shopping Class Constructor
	*
	* The constructor loads the Session class, used to store the shopping cart contents.
	*
	* @param array
	* @return void
	*/
	public function __construct($params = array())
	{
	// Set the super object to a local variable for use later
	$this->CI =& get_instance();

	// Are any config settings being passed manually? If so, set them
	$config = is_array($params) ? $params : array();

	// Load the Sessions class
	$this->CI->load->driver('session', $config);

	// Grab the shopping cart array from the session table
	$this->_cart_contents = $this->CI->session->userdata('cart_contents');
	if ($this->_cart_contents === NULL)
	{
	// No cart exists so we'll set some base values
	$this->_cart_contents = array('cart_total' => 0, 'total_items' => 0);
	}

	log_message('info', 'Cart Class Initialized');
	}

	// --------------------------------------------------------------------

	/**
	* Insert items into the cart and save it to the session table
	*
	* @param array
	* @return bool
	*/
	public function insert($items = array())
	{
	// Was any cart data passed? No? Bah...
	if ( ! is_array($items) OR count($items) === 0)
	{
	log_message('error', 'The insert method must be passed an array containing data.');
	return FALSE;
	}

	// You can either insert a single product using a one-dimensional array,
	// or multiple products using a multi-dimensional one. The way we
	// determine the array type is by looking for a required array key named "id"
	// at the top level. If it's not found, we will assume it's a multi-dimensional array.

	$save_cart = FALSE;
	if (isset($items['id']))
	{
	if (($rowid = $this->_insert($items)))
	{
	$save_cart = TRUE;
	}
	}
	else
	{
	foreach ($items as $val)
	{
	if (is_array($val) && isset($val['id']))
	{
	if ($this->_insert($val))
	{
	$save_cart = TRUE;
	}
	}
	}
	}

	// Save the cart data if the insert was successful
	if ($save_cart === TRUE)
	{
	$this->_save_cart();
	return isset($rowid) ? $rowid : TRUE;
	}

	return FALSE;
	}

	// --------------------------------------------------------------------

	/**
	* Insert
	*
	* @param array
	* @return bool
	*/
	protected function _insert($items = array())
	{
	// Was any cart data passed? No? Bah...
	if ( ! is_array($items) OR count($items) === 0)
	{
	log_message('error', 'The insert method must be passed an array containing data.');
	return FALSE;
	}

	// --------------------------------------------------------------------

	// Does the $items array contain an id, quantity, price, and name? These are required
	if ( ! isset($items['id'], $items['qty'], $items['price'], $items['name']))
	{
	log_message('error', 'The cart array must contain a product ID, quantity, price, and name.');
	return FALSE;
	}

	// --------------------------------------------------------------------

	// Prep the quantity. It can only be a number. Duh... also trim any leading zeros
	$items['qty'] = (float) $items['qty'];

	// If the quantity is zero or blank there's nothing for us to do
	if ($items['qty'] == 0)
	{
	return FALSE;
	}

	// --------------------------------------------------------------------

	// Validate the product ID. It can only be alpha-numeric, dashes, underscores or periods
	// Not totally sure we should impose this rule, but it seems prudent to standardize IDs.
	// Note: These can be user-specified by setting the $this->product_id_rules variable.
	if ( ! preg_match('/^['.$this->product_id_rules.']+$/i', $items['id']))
	{
	log_message('error', 'Invalid product ID. The product ID can only contain alpha-numeric characters, dashes, and underscores');
	return FALSE;
	}

	// --------------------------------------------------------------------

	// Validate the product name. It can only be alpha-numeric, dashes, underscores, colons or periods.
	// Note: These can be user-specified by setting the $this->product_name_rules variable.
	if ($this->product_name_safe && ! preg_match('/^['.$this->product_name_rules.']+$/i'.(UTF8_ENABLED ? 'u' : ''), $items['name']))
	{
	log_message('error', 'An invalid name was submitted as the product name: '.$items['name'].' The name can only contain alpha-numeric characters, dashes, underscores, colons, and spaces');
	return FALSE;
	}

	// --------------------------------------------------------------------

	// Prep the price. Remove leading zeros and anything that isn't a number or decimal point.
	$items['price'] = (float) $items['price'];

	// We now need to create a unique identifier for the item being inserted into the cart.
	// Every time something is added to the cart it is stored in the master cart array.
	// Each row in the cart array, however, must have a unique index that identifies not only
	// a particular product, but makes it possible to store identical products with different options.
	// For example, what if someone buys two identical t-shirts (same product ID), but in
	// different sizes? The product ID (and other attributes, like the name) will be identical for
	// both sizes because it's the same shirt. The only difference will be the size.
	// Internally, we need to treat identical submissions, but with different options, as a unique product.
	// Our solution is to convert the options array to a string and MD5 it along with the product ID.
	// This becomes the unique "row ID"
	if (isset($items['options']) && count($items['options']) > 0)
	{
	$rowid = md5($items['id'].serialize($items['options']));
	}
	else
	{
	// No options were submitted so we simply MD5 the product ID.
	// Technically, we don't need to MD5 the ID in this case, but it makes
	// sense to standardize the format of array indexes for both conditions
	$rowid = md5($items['id']);
	}

	// --------------------------------------------------------------------

	// Now that we have our unique "row ID", we'll add our cart items to the master array
	// grab quantity if it's already there and add it on
	$old_quantity = isset($this->_cart_contents[$rowid]['qty']) ? (int) $this->_cart_contents[$rowid]['qty'] : 0;

	// Re-create the entry, just to make sure our index contains only the data from this submission
	$items['rowid'] = $rowid;
	$items['qty'] += $old_quantity;
	$this->_cart_contents[$rowid] = $items;

	return $rowid;
	}

	// --------------------------------------------------------------------

	/**
	* Update the cart
	*
	* This function permits the quantity of a given item to be changed.
	* Typically it is called from the "view cart" page if a user makes
	* changes to the quantity before checkout. That array must contain the
	* product ID and quantity for each item.
	*
	* @param array
	* @return bool
	*/
	public function update($items = array())
	{
	// Was any cart data passed?
	if ( ! is_array($items) OR count($items) === 0)
	{
	return FALSE;
	}

	// You can either update a single product using a one-dimensional array,
	// or multiple products using a multi-dimensional one. The way we
	// determine the array type is by looking for a required array key named "rowid".
	// If it's not found we assume it's a multi-dimensional array
	$save_cart = FALSE;
	if (isset($items['rowid']))
	{
	if ($this->_update($items) === TRUE)
	{
	$save_cart = TRUE;
	}
	}
	else
	{
	foreach ($items as $val)
	{
	if (is_array($val) && isset($val['rowid']))
	{
	if ($this->_update($val) === TRUE)
	{
	$save_cart = TRUE;
	}
	}
	}
	}

	// Save the cart data if the insert was successful
	if ($save_cart === TRUE)
	{
	$this->_save_cart();
	return TRUE;
	}

	return FALSE;
	}

	// --------------------------------------------------------------------

	/**
	* Update the cart
	*
	* This function permits changing item properties.
	* Typically it is called from the "view cart" page if a user makes
	* changes to the quantity before checkout. That array must contain the
	* rowid and quantity for each item.
	*
	* @param array
	* @return bool
	*/
	protected function _update($items = array())
	{
	// Without these array indexes there is nothing we can do
	if ( ! isset($items['rowid'], $this->_cart_contents[$items['rowid']]))
	{
	return FALSE;
	}

	// Prep the quantity
	if (isset($items['qty']))
	{
	$items['qty'] = (float) $items['qty'];
	// Is the quantity zero? If so we will remove the item from the cart.
	// If the quantity is greater than zero we are updating
	if ($items['qty'] == 0)
	{
	unset($this->_cart_contents[$items['rowid']]);
	return TRUE;
	}
	}

	// find updatable keys
	$keys = array_intersect(array_keys($this->_cart_contents[$items['rowid']]), array_keys($items));
	// if a price was passed, make sure it contains valid data
	if (isset($items['price']))
	{
	$items['price'] = (float) $items['price'];
	}

	// product id & name shouldn't be changed
	foreach (array_diff($keys, array('id', 'name')) as $key)
	{
	$this->_cart_contents[$items['rowid']][$key] = $items[$key];
	}

	return TRUE;
	}

	// --------------------------------------------------------------------

	/**
	* Save the cart array to the session DB
	*
	* @return bool
	*/
	protected function _save_cart()
	{
	// Let's add up the individual prices and set the cart sub-total
	$this->_cart_contents['total_items'] = $this->_cart_contents['cart_total'] = 0;
	foreach ($this->_cart_contents as $key => $val)
	{
	// We make sure the array contains the proper indexes
	if ( ! is_array($val) OR ! isset($val['price'], $val['qty']))
	{
	continue;
	}

	$this->_cart_contents['cart_total'] += ($val['price'] * $val['qty']);
	$this->_cart_contents['total_items'] += $val['qty'];
	$this->_cart_contents[$key]['subtotal'] = ($this->_cart_contents[$key]['price'] * $this->_cart_contents[$key]['qty']);
	}

	// Is our cart empty? If so we delete it from the session
	if (count($this->_cart_contents) <= 2)
	{
	$this->CI->session->unset_userdata('cart_contents');

	// Nothing more to do... coffee time!
	return FALSE;
	}

	// If we made it this far it means that our cart has data.
	// Let's pass it to the Session class so it can be stored
	$this->CI->session->set_userdata(array('cart_contents' => $this->_cart_contents));

	// Woot!
	return TRUE;
	}

	// --------------------------------------------------------------------

	/**
	* Cart Total
	*
	* @return int
	*/
	public function total()
	{
	return $this->_cart_contents['cart_total'];
	}

	// --------------------------------------------------------------------

	/**
	* Remove Item
	*
	* Removes an item from the cart
	*
	* @param int
	* @return bool
	*/
	public function remove($rowid)
	{
	// unset & save
	unset($this->_cart_contents[$rowid]);
	$this->_save_cart();
	return TRUE;
	}

	// --------------------------------------------------------------------

	/**
	* Total Items
	*
	* Returns the total item count
	*
	* @return int
	*/
	public function total_items()
	{
	return $this->_cart_contents['total_items'];
	}

	// --------------------------------------------------------------------

	/**
	* Cart Contents
	*
	* Returns the entire cart array
	*
	* @param bool
	* @return array
	*/
	public function contents($newest_first = FALSE)
	{
	// do we want the newest first?
	$cart = ($newest_first) ? array_reverse($this->_cart_contents) : $this->_cart_contents;

	// Remove these so they don't create a problem when showing the cart table
	unset($cart['total_items']);
	unset($cart['cart_total']);

	return $cart;
	}

	// --------------------------------------------------------------------

	/**
	* Get cart item
	*
	* Returns the details of a specific item in the cart
	*
	* @param string $row_id
	* @return array
	*/
	public function get_item($row_id)
	{
	return (in_array($row_id, array('total_items', 'cart_total'), TRUE) OR ! isset($this->_cart_contents[$row_id]))
	? FALSE
	: $this->_cart_contents[$row_id];
	}

	// --------------------------------------------------------------------

	/**
	* Has options
	*
	* Returns TRUE if the rowid passed to this function correlates to an item
	* that has options associated with it.
	*
	* @param string $row_id = ''
	* @return bool
	*/
	public function has_options($row_id = '')
	{
	return (isset($this->_cart_contents[$row_id]['options']) && count($this->_cart_contents[$row_id]['options']) !== 0);
	}

	// --------------------------------------------------------------------

	/**
	* Product options
	*
	* Returns the an array of options, for a particular product row ID
	*
	* @param string $row_id = ''
	* @return array
	*/
	public function product_options($row_id = '')
	{
	return isset($this->_cart_contents[$row_id]['options']) ? $this->_cart_contents[$row_id]['options'] : array();
	}

	// --------------------------------------------------------------------

	/**
	* Format Number
	*
	* Returns the supplied number with commas and a decimal point.
	*
	* @param float
	* @return string
	*/
	public function format_number($n = '')
	{
	return ($n === '') ? '' : number_format( (float) $n, 2, '.', ',');
	}

	// --------------------------------------------------------------------

	/**
	* Destroy the cart
	*
	* Empties the cart and kills the session
	*
	* @return void
	*/
	public function destroy()
	{
	$this->_cart_contents = array('cart_total' => 0, 'total_items' => 0);
	$this->CI->session->unset_userdata('cart_contents');
	}

	}