<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * If you did not receive a copy of the license and are unable to

 * obtain it through the world-wide-web, please send an email

 * to license@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Locale

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 * @version    $Id: PhpMath.php 20096 2010-01-06 02:05:09Z bkarwin $

 */

/**

 * Utility class for proxying math function to bcmath functions, if present,

 * otherwise to PHP builtin math operators, with limited detection of overflow conditions.

 * Sampling of PHP environments and platforms suggests that at least 80% to 90% support bcmath.

 * This file should only be loaded for the 10% to 20% lacking access to the bcmath extension.

 *

 * @category   Zend

 * @package    Zend_Locale

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

class Zend_Locale_Math_PhpMath extends Zend_Locale_Math

{

    public static function disable()

    {

        self::$_bcmathDisabled = true;

        self::$add   = array('Zend_Locale_Math_PhpMath', 'Add');

        self::$sub   = array('Zend_Locale_Math_PhpMath', 'Sub');

        self::$pow   = array('Zend_Locale_Math_PhpMath', 'Pow');

        self::$mul   = array('Zend_Locale_Math_PhpMath', 'Mul');

        self::$div   = array('Zend_Locale_Math_PhpMath', 'Div');

        self::$comp  = array('Zend_Locale_Math_PhpMath', 'Comp');

        self::$sqrt  = array('Zend_Locale_Math_PhpMath', 'Sqrt');

        self::$mod   = array('Zend_Locale_Math_PhpMath', 'Mod');

        self::$scale = array('Zend_Locale_Math_PhpMath', 'Scale');

        self::$defaultScale     = 0;

        self::$defaultPrecision = 1;

    }

    public static $defaultScale;

    public static $defaultPrecision;

    public static function Add($op1, $op2, $scale = null)

    {

        if ($scale === null) {

            $scale     = Zend_Locale_Math_PhpMath::$defaultScale;

            $precision = Zend_Locale_Math_PhpMath::$defaultPrecision;

        } else {

            $precision = pow(10, -$scale);

        }

        if (empty($op1)) {

            $op1 = 0;

        }

        $op1 = self::normalize($op1);

        $op2 = self::normalize($op2);

        $result = $op1 + $op2;

        if (is_infinite($result)  or  (abs($result - $op2 - $op1) > $precision)) {

            require_once 'Zend/Locale/Math/Exception.php';

            throw new Zend_Locale_Math_Exception("addition overflow: $op1 + $op2 != $result", $op1, $op2, $result);

        }

        return self::round(self::normalize($result), $scale);

    }

    public static function Sub($op1, $op2, $scale = null)

    {

        if ($scale === null) {

            $scale     = Zend_Locale_Math_PhpMath::$defaultScale;

            $precision = Zend_Locale_Math_PhpMath::$defaultPrecision;

        } else {

            $precision = pow(10, -$scale);

        }

        if (empty($op1)) {

            $op1 = 0;

        }

        $op1  = self::normalize($op1);

        $op2  = self::normalize($op2);

        $result = $op1 - $op2;

        if (is_infinite($result)  or  (abs($result + $op2 - $op1) > $precision)) {

            require_once 'Zend/Locale/Math/Exception.php';

            throw new Zend_Locale_Math_Exception("subtraction overflow: $op1 - $op2 != $result", $op1, $op2, $result);

        }

        return self::round(self::normalize($result), $scale);

    }

    public static function Pow($op1, $op2, $scale = null)

    {

        if ($scale === null) {

            $scale = Zend_Locale_Math_PhpMath::$defaultScale;

        }

        $op1 = self::normalize($op1);

        $op2 = self::normalize($op2);

        // BCMath extension doesn't use decimal part of the power

        // Provide the same behavior

        $op2 = ($op2 > 0) ? floor($op2) : ceil($op2);

        $result = pow($op1, $op2);

        if (is_infinite($result)  or  is_nan($result)) {

            require_once 'Zend/Locale/Math/Exception.php';

            throw new Zend_Locale_Math_Exception("power overflow: $op1 ^ $op2", $op1, $op2, $result);

        }

        return self::round(self::normalize($result), $scale);

    }

    public static function Mul($op1, $op2, $scale = null)

    {

        if ($scale === null) {

            $scale = Zend_Locale_Math_PhpMath::$defaultScale;

        }

        if (empty($op1)) {

            $op1 = 0;

        }

        $op1 = self::normalize($op1);

        $op2 = self::normalize($op2);

        $result = $op1 * $op2;

        if (is_infinite($result)  or  is_nan($result)) {

            require_once 'Zend/Locale/Math/Exception.php';

            throw new Zend_Locale_Math_Exception("multiplication overflow: $op1 * $op2 != $result", $op1, $op2, $result);

        }

        return self::round(self::normalize($result), $scale);

    }

    public static function Div($op1, $op2, $scale = null)

    {

        if ($scale === null) {

            $scale = Zend_Locale_Math_PhpMath::$defaultScale;

        }

        if (empty($op2)) {

            require_once 'Zend/Locale/Math/Exception.php';

            throw new Zend_Locale_Math_Exception("can not divide by zero", $op1, $op2, null);

        }

        if (empty($op1)) {

            $op1 = 0;

        }

        $op1 = self::normalize($op1);

        $op2 = self::normalize($op2);

        $result = $op1 / $op2;

        if (is_infinite($result)  or  is_nan($result)) {

            require_once 'Zend/Locale/Math/Exception.php';

            throw new Zend_Locale_Math_Exception("division overflow: $op1 / $op2 != $result", $op1, $op2, $result);

        }

        return self::round(self::normalize($result), $scale);

    }

    public static function Sqrt($op1, $scale = null)

    {

        if ($scale === null) {

            $scale = Zend_Locale_Math_PhpMath::$defaultScale;

        }

        if (empty($op1)) {

            $op1 = 0;

        }

        $op1 = self::normalize($op1);

        $result = sqrt($op1);

        if (is_nan($result)) {

            return NULL;

        }

        return self::round(self::normalize($result), $scale);

    }

    public static function Mod($op1, $op2)

    {

        if (empty($op1)) {

            $op1 = 0;

        }

        if (empty($op2)) {

            return NULL;

        }

        $op1 = self::normalize($op1);

        $op2 = self::normalize($op2);

        if ((int)$op2 == 0) {

            return NULL;

        }

        $result = $op1 % $op2;

        if (is_nan($result)  or  (($op1 - $result) % $op2 != 0)) {

            require_once 'Zend/Locale/Math/Exception.php';

            throw new Zend_Locale_Math_Exception("modulus calculation error: $op1 % $op2 != $result", $op1, $op2, $result);

        }

        return self::normalize($result);

    }

    public static function Comp($op1, $op2, $scale = null)

    {

        if ($scale === null) {

            $scale     = Zend_Locale_Math_PhpMath::$defaultScale;

        }

        if (empty($op1)) {

            $op1 = 0;

        }

        $op1 = self::normalize($op1);

        $op2 = self::normalize($op2);

        if ($scale <> 0) {

            $op1 = self::round($op1, $scale);

            $op2 = self::round($op2, $scale);

        } else {

            $op1 = ($op1 > 0) ? floor($op1) : ceil($op1);

            $op2 = ($op2 > 0) ? floor($op2) : ceil($op2);

        }

        if ($op1 > $op2) {

            return 1;

        } else if ($op1 < $op2) {

            return -1;

        }

        return 0;

    }

    public static function Scale($scale)

    {

        if ($scale > 9) {

            require_once 'Zend/Locale/Math/Exception.php';

            throw new Zend_Locale_Math_Exception("can not scale to precision $scale", $scale, null, null);

        }

        self::$defaultScale     = $scale;

        self::$defaultPrecision = pow(10, -$scale);

        return true;

    }

}

Zend_Locale_Math_PhpMath::disable(); // disable use of bcmath functions