1: <?php
 2: /**
 3:  * Magento
 4:  *
 5:  * NOTICE OF LICENSE
 6:  *
 7:  * This source file is subject to the Open Software License (OSL 3.0)
 8:  * that is bundled with this package in the file LICENSE.txt.
 9:  * It is also available through the world-wide-web at this URL:
10:  * http://opensource.org/licenses/osl-3.0.php
11:  * If you did not receive a copy of the license and are unable to
12:  * obtain it through the world-wide-web, please send an email
13:  * to license@magentocommerce.com so we can send you a copy immediately.
14:  *
15:  * DISCLAIMER
16:  *
17:  * Do not edit or add to this file if you wish to upgrade Magento to newer
18:  * versions in the future. If you wish to customize Magento for your
19:  * needs please refer to http://www.magentocommerce.com for more information.
20:  *
21:  * @category    Mage
22:  * @package     Mage_Core
23:  * @copyright   Copyright (c) 2012 Magento Inc. (http://www.magentocommerce.com)
24:  * @license     http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
25:  */
26: 
27: 
28: /**
29:  * Calculations model
30:  *
31:  * @category    Mage
32:  * @package     Mage_Core
33:  * @author      Magento Core Team <core@magentocommerce.com>
34:  */
35: class Mage_Core_Model_Calculator
36: {
37:     /**
38:      * Delta collected during rounding steps
39:      *
40:      * @var float
41:      */
42:     protected $_delta = 0.0;
43: 
44:     /**
45:      * Store instance
46:      *
47:      * @var Mage_Core_Model_Store|null
48:      */
49:     protected $_store = null;
50: 
51:     /**
52:      * Initialize calculator
53:      *
54:      * @param Mage_Core_Model_Store|int $store
55:      */
56:     public function __construct($store)
57:     {
58:         if (!($store instanceof Mage_Core_Model_Store)) {
59:             $store = Mage::app()->getStore($store);
60:         }
61:         $this->_store = $store;
62:     }
63: 
64:     /**
65:      * Round price considering delta
66:      *
67:      * @param float $price
68:      * @param bool $negative Indicates if we perform addition (true) or subtraction (false) of rounded value
69:      * @return float
70:      */
71:     public function deltaRound($price, $negative = false)
72:     {
73:         $roundedPrice = $price;
74:         if ($roundedPrice) {
75:             if ($negative) {
76:                 $this->_delta = -$this->_delta;
77:             }
78:             $price  += $this->_delta;
79:             $roundedPrice = $this->_store->roundPrice($price);
80:             $this->_delta = $price - $roundedPrice;
81:             if ($negative) {
82:                 $this->_delta = -$this->_delta;
83:             }
84:         }
85:         return $roundedPrice;
86:     }
87: }
88: