BC - Code Metrics - Inspection of "added bitwise xor, or and "and" #20" - krowinski/bcmath-extended - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Pull Request — master (#28)

by kacper

created 2018-12-05 22:21 UTC

BC F

↳ Parent: Project

Complexity

Total Complexity

109

Size/Duplication

Total Lines	787
Duplicated Lines	17.28 %

Coupling/Cohesion

Components	1
Dependencies	0

Test Coverage

Coverage

99.03%

Importance

Changes

Metric	Value
wmc	109
lcom	1
cbo	0
dl	136
loc	787
ccs	307
cts	310
cp	0.9903
rs	1.813
c	0
b	0
f	0

41 Methods

Rating	Name	Duplication	Size	Complexity
A	round()	0	13	3
A	convertScientificNotationToString()	0	20	4
A	getDecimalsLengthFromNumber()	0	9	2
A	pow()	0	19	4
A	checkIsFloat()	0	4	1
A	powFractional()	0	21	2
A	getScale()	0	6	1
A	sqrt()	0	10	2
A	checkNumber()	0	9	3
A	mul()	11	11	2
A	exp()	0	10	2
A	add()	11	11	2
A	div()	11	11	2
A	log()	0	28	5
A	comp()	0	15	2
A	sub()	11	11	2
A	isNegative()	0	4	1
A	rand()	0	10	1
A	max()	18	18	5
A	min()	18	18	5
A	roundDown()	15	17	2
A	floor()	13	13	4
A	checkIsFloatCleanZeros()	0	4	1
A	roundUp()	15	17	2
A	ceil()	13	13	4
A	powMod()	0	17	5
A	mod()	0	16	2
A	fact()	0	18	4
A	hexdec()	0	11	2
A	dechex()	0	11	2
A	bitAnd()	0	4	1
C	bitOperatorHelper()	0	51	12
A	dec2bin()	0	17	3
A	decBaseHelper()	0	14	3
A	setScale()	0	4	1
A	abs()	0	10	2
A	alignBinLength()	0	4	1
A	recalculateNegative()	0	15	3
A	bin2dec()	0	14	2
A	bitOr()	0	4	1
A	bitXor()	0	4	1

How to fix Duplicated Code Complexity

Duplicated Code

Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.

Common duplication problems, and corresponding solutions are:

If you have the same expression in different places: Extract expression to a method
If you have the same method in different sub-classes: Extract method, and pull up field to the parent class
If you have the same code in unrelated classes: Consider extracting the code to a new class, and injecting that class

Complex Class

Tip: Before tackling complexity, make sure that you eliminate any duplication first. This often can reduce the size of classes significantly.

Complex classes like BC often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.

Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.

While breaking up the class, it is a good idea to analyze how other classes use BC, and based on these observations, apply Extract Interface, too.

<?php

namespace BCMathExtended;

/**
 * Class BC
 * @package BCMathExtended
 */
class BC
{
    const COMPARE_EQUAL = 0;
    const COMPARE_LEFT_GRATER = 1;
    const COMPARE_RIGHT_GRATER = -1;

    const DEFAULT_SCALE = 100;

    const MAX_BASE = 256;

    const BIT_OPERATOR_AND = 'and';
    const BIT_OPERATOR_OR = 'or';
    const BIT_OPERATOR_XOR = 'xor';

    /**
     * @param int|string $number
     * @param int $precision
     * @return string
     */
    public static function round($number, $precision = 0)
    {
        $number = self::convertScientificNotationToString($number);
        if (self::checkIsFloat($number)) {
            if (self::isNegative($number)) {
                return self::sub($number, '0.' . str_repeat('0', $precision) . '5', $precision);
            }

            return self::add($number, '0.' . str_repeat('0', $precision) . '5', $precision);
        }

        return self::checkNumber($number);
    }

    /**
     * @param int|string|float $number
     * @return string
     */
    public static function convertScientificNotationToString($number)
    {
        // check if number is in scientific notation, first use stripos as is faster then preg_match
        if (false !== stripos($number, 'E') && preg_match('/(-?(\d+\.)?\d+)E([+-]?)(\d+)/i', $number, $regs)) {
            // calculate final scale of number
            $scale = $regs[4] + self::getDecimalsLengthFromNumber($regs[1]);
            $pow = self::pow(10, $regs[4], $scale);
            if ('-' === $regs[3]) {
                $number = self::div($regs[1], $pow, $scale);
            } else {
                $number = self::mul($pow, $regs[1], $scale);
            }
            // remove unnecessary 0 from 0.000 is a 0
            $number = rtrim($number, '0');
            // if you remove 0 you must clean dot
            $number = rtrim($number, '.');
        }

        return self::checkNumber($number);
    }

    /**
     * @param int|string|float $number
     * @return int
     */
    public static function getDecimalsLengthFromNumber($number)
    {
        $check = explode('.', $number);
        if (!empty($check[1])) {
            return strlen($check[1]);
        }

        return 0;
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @param null|int $scale
     * @return string
     */
    public static function pow($leftOperand, $rightOperand, $scale = null)
    {
        $leftOperand = self::convertScientificNotationToString($leftOperand);
        $rightOperand = self::convertScientificNotationToString($rightOperand);

        if (self::checkIsFloat($rightOperand)) {
            if (null === $scale) {
                return self::powFractional($leftOperand, $rightOperand);
            }

            return self::powFractional($leftOperand, $rightOperand, $scale);
        }

        if (null === $scale) {
            return bcpow($leftOperand, $rightOperand);
        }

        return bcpow($leftOperand, $rightOperand, $scale);
    }

    /**
     * @param int|string $number
     * @return bool
     */
    private static function checkIsFloat($number)
    {
        return false !== strpos($number, '.');
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @param null|int $scale
     * @return string
     */
    private static function powFractional($leftOperand, $rightOperand, $scale = null)
    {
        // we need to increased scale to get correct results and avoid rounding error
        $increasedScale = null === $scale ? self::getScale() : $scale;
        $increasedScale *= 2;
        $decimals = explode('.', $rightOperand);

        return self::checkNumber(
            self::mul(
                self::exp(
                    self::mul(
                        self::log($leftOperand),
                        '0.' . $decimals[1],
                        $increasedScale
                    )
                ),
                self::pow($leftOperand, $decimals[0], $increasedScale),
                $scale
            )
        );
    }

    /**
     * @return int
     */
    public static function getScale()
    {
        $sqrt = self::sqrt('2');

        return strlen(substr($sqrt, strpos($sqrt, '.') + 1));
    }

    /**
     * @param string $operand
     * @param null|int $scale
     * @return string
     */
    public static function sqrt($operand, $scale = null)
    {
        $operand = self::convertScientificNotationToString($operand);

        if (null === $scale) {
            return bcsqrt($operand);
        }

        return bcsqrt($operand, $scale);
    }

    /**
     * @param int|string $number
     * @return int|string
     */
    private static function checkNumber($number)
    {
        $number = str_replace('+', '', filter_var($number, FILTER_SANITIZE_NUMBER_FLOAT, FILTER_FLAG_ALLOW_FRACTION));
        if ('-0' === $number || !is_numeric($number)) {
            return '0';
        }

        return $number;
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @param null|int $scale
     * @return string
     */
    public static function mul($leftOperand, $rightOperand, $scale = null)
    {
        $leftOperand = self::convertScientificNotationToString($leftOperand);
        $rightOperand = self::convertScientificNotationToString($rightOperand);

        if (null === $scale) {
            return bcmul($leftOperand, $rightOperand);
        }

        return bcmul($leftOperand, $rightOperand, $scale);
    }

    /**
     * @param string $arg
     * @return string
     */
    public static function exp($arg)
    {
        $scale = self::DEFAULT_SCALE;
        $result = '1';
        for ($i = 299; $i > 0; $i--) {
            $result = self::add(self::mul(self::div($result, $i, $scale), $arg, $scale), 1, $scale);
        }

        return $result;
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @param null|int $scale
     * @return string
     */
    public static function add($leftOperand, $rightOperand, $scale = null)
    {
        $leftOperand = self::convertScientificNotationToString($leftOperand);
        $rightOperand = self::convertScientificNotationToString($rightOperand);

        if (null === $scale) {
            return bcadd($leftOperand, $rightOperand);
        }

        return bcadd($leftOperand, $rightOperand, $scale);
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @param null|int $scale
     * @return string
     */
    public static function div($leftOperand, $rightOperand, $scale = null)
    {
        $leftOperand = self::convertScientificNotationToString($leftOperand);
        $rightOperand = self::convertScientificNotationToString($rightOperand);

        if (null === $scale) {
            return bcdiv($leftOperand, $rightOperand);
        }

        return bcdiv($leftOperand, $rightOperand, $scale);
    }

    /**
     * @param string $arg
     * @return string
     */
    public static function log($arg)
    {
        $arg = self::convertScientificNotationToString($arg);
        if ($arg === '0') {
            return '-INF';
        }
        if (self::COMPARE_RIGHT_GRATER === self::comp($arg, '0')) {
            return 'NAN';
        }
        $scale = self::DEFAULT_SCALE;
        $m = (string)log($arg);
        $x = self::sub(self::div($arg, self::exp($m), $scale), '1', $scale);
        $res = '0';
        $pow = '1';
        $i = 1;
        do {
            $pow = self::mul($pow, $x, $scale);
            $sum = self::div($pow, $i, $scale);
            if ($i % 2 === 1) {
                $res = self::add($res, $sum, $scale);
            } else {
                $res = self::sub($res, $sum, $scale);
            }
            $i++;
        } while (self::comp($sum, '0', $scale));

        return self::add($res, $m, $scale);
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @param null|int $scale
     * @return int
     */
    public static function comp($leftOperand, $rightOperand, $scale = null)
    {
        $leftOperand = self::convertScientificNotationToString($leftOperand);
        $rightOperand = self::convertScientificNotationToString($rightOperand);

        if (null === $scale) {
            return bccomp($leftOperand, $rightOperand, max(strlen($leftOperand), strlen($rightOperand)));
        }

        return bccomp(
            $leftOperand,
            $rightOperand,
            $scale
        );
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @param null|int $scale
     * @return string
     */
    public static function sub($leftOperand, $rightOperand, $scale = null)
    {
        $leftOperand = self::convertScientificNotationToString($leftOperand);
        $rightOperand = self::convertScientificNotationToString($rightOperand);

        if (null === $scale) {
            return bcsub($leftOperand, $rightOperand);
        }

        return bcsub($leftOperand, $rightOperand, $scale);
    }

    /**
     * @param $number
     * @return bool
     */
    private static function isNegative($number)
    {
        return 0 === strncmp('-', $number, 1);
    }

    /**
     * @param int|string $min
     * @param int|string $max
     * @return string
     */
    public static function rand($min, $max)
    {
        $max = self::convertScientificNotationToString($max);
        $min = self::convertScientificNotationToString($min);

        $difference = self::add(self::sub($max, $min), 1);
        $randPercent = self::div(mt_rand(), mt_getrandmax(), 8);

        return self::add($min, self::mul($difference, $randPercent, 8), 0);
    }

    /**
     * @param array|int|string,...
     * @return null|string
     */
    public static function max()

    {
        $max = null;
        $args = func_get_args();
        if (is_array($args[0])) {
            $args = $args[0];
        }
        foreach ($args as $number) {
            $number = self::convertScientificNotationToString($number);
            if (null === $max) {
                $max = $number;
            } elseif (self::comp($max, $number) === self::COMPARE_RIGHT_GRATER) {
                $max = $number;
            }
        }

        return $max;
    }

    /**
     * @param array|int|string,...
     * @return null|string
     */
    public static function min()

    {
        $min = null;
        $args = func_get_args();
        if (is_array($args[0])) {
            $args = $args[0];
        }
        foreach ($args as $number) {
            $number = self::convertScientificNotationToString($number);
            if (null === $min) {
                $min = $number;
            } elseif (self::comp($min, $number) === self::COMPARE_LEFT_GRATER) {
                $min = $number;
            }
        }

        return $min;
    }

    /**
     * @param int|string $number
     * @param int $precision
     * @return string
     */
    public static function roundDown($number, $precision = 0)

    {
        $number = self::convertScientificNotationToString($number);
        $multiply = self::pow(10, (string)abs($precision));

        return $precision < 0
            ?
            self::mul(
                self::floor(self::div($number, $multiply, self::getDecimalsLengthFromNumber($number))), $multiply,
                $precision
            )
            :
            self::div(
                self::floor(self::mul($number, $multiply, self::getDecimalsLengthFromNumber($number))), $multiply,
                $precision
            );
    }

    /**
     * @param int|string $number
     * @return string
     */
    public static function floor($number)

    {
        $number = self::convertScientificNotationToString($number);
        if (self::checkIsFloat($number) && self::checkIsFloatCleanZeros($number)) {
            $result = 0;
            if (self::isNegative($number)) {
                --$result;
            }
            $number = self::add($number, $result, 0);
        }

        return self::checkNumber($number);
    }

    /**
     * @param int|string $number
     * @return bool
     */
    private static function checkIsFloatCleanZeros(&$number)
    {
        return false !== strpos($number = rtrim(rtrim($number, '0'), '.'), '.');
    }

    /**
     * @param int|string $number
     * @param int $precision
     * @return string
     */
    public static function roundUp($number, $precision = 0)

    {
        $number = self::convertScientificNotationToString($number);
        $multiply = self::pow(10, (string)abs($precision));

        return $precision < 0
            ?
            self::mul(
                self::ceil(self::div($number, $multiply, self::getDecimalsLengthFromNumber($number))), $multiply,
                $precision
            )
            :
            self::div(
                self::ceil(self::mul($number, $multiply, self::getDecimalsLengthFromNumber($number))), $multiply,
                $precision
            );
    }

    /**
     * @param int|string $number
     * @return string
     */
    public static function ceil($number)

    {
        $number = self::convertScientificNotationToString($number);
        if (self::checkIsFloat($number) && self::checkIsFloatCleanZeros($number)) {
            $result = 1;
            if (self::isNegative($number)) {
                --$result;
            }
            $number = self::add($number, $result, 0);
        }

        return self::checkNumber($number);
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @param string $modulus
     * @param null|int $scale
     * @return string
     */
    public static function powMod($leftOperand, $rightOperand, $modulus, $scale = null)
    {
        $leftOperand = self::convertScientificNotationToString($leftOperand);
        $rightOperand = self::convertScientificNotationToString($rightOperand);

        // bcpowmod in 5.6 have don't calculate correct results if scale is empty
        if (null === $scale) {
            return self::mod(self::pow($leftOperand, $rightOperand), $modulus);
        }

        // cant use bcpowmod here as it don't support floats
        if (self::checkIsFloat($leftOperand) || self::checkIsFloat($rightOperand) || self::checkIsFloat($modulus)) {
            return self::mod(self::pow($leftOperand, $rightOperand, $scale), $modulus, $scale);
        }

        return bcpowmod($leftOperand, $rightOperand, $modulus, $scale);
    }

    /**
     * @param string $leftOperand
     * @param string $modulus
     * @param null $scale
     * @return string
     */
    public static function mod($leftOperand, $modulus, $scale = null)
    {
        $leftOperand = self::convertScientificNotationToString($leftOperand);

        // bcmod in 7.2 is not working properly - for example bcmod(9.9999E-10, -0.00056, 9) should return '-0.000559999' but returns 0.0000000

        // bcmod in php 5.6< don't support scale and floats
        // let use this $x - floor($x/$y) * $y;
        if (null === $scale) {
            return self::sub($leftOperand, self::mul(self::floor(self::div($leftOperand, $modulus)), $modulus));
        }

        return self::sub(
            $leftOperand, self::mul(self::floor(self::div($leftOperand, $modulus, $scale)), $modulus, $scale), $scale
        );
    }

    /**
     * @param string $arg
     * @return string
     * @throws \InvalidArgumentException
     */
    public static function fact($arg)
    {
        $arg = self::convertScientificNotationToString($arg);

        if (self::checkIsFloat($arg)) {
            throw new \InvalidArgumentException('Number has to be an integer');
        }
        if (self::isNegative($arg)) {
            throw new \InvalidArgumentException('Number has to be greater than or equal to 0');
        }

        $return = '1';
        for ($i = 2; $i <= $arg; ++$i) {
            $return = self::mul($return, $i);
        }

        return $return;
    }

    /**
     * @param string $hex
     * @return string
     */
    public static function hexdec($hex)
    {
        $remainingDigits = substr($hex, 0, -1);
        $lastDigitToDecimal = \hexdec(substr($hex, -1));

        if ('' === $remainingDigits) {
            return $lastDigitToDecimal;
        }

        return self::add(self::mul(16, self::hexdec($remainingDigits)), $lastDigitToDecimal, 0);
    }

    /**
     * @param int $decimal
     * @return string
     */
    public static function dechex($decimal)
    {
        $quotient = self::div($decimal, 16, 0);
        $remainderToHex = \dechex(self::mod($decimal, 16));

        if (self::comp($quotient, 0) === 0) {
            return $remainderToHex;
        }

        return self::dechex($quotient) . $remainderToHex;
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @return string
     */
    public static function bitAnd($leftOperand, $rightOperand)
    {
        return self::bitOperatorHelper($leftOperand, $rightOperand, self::BIT_OPERATOR_AND);
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @param string $operator
     * @return string
     */
    private static function bitOperatorHelper($leftOperand, $rightOperand, $operator)
    {
        $leftOperand = self::convertScientificNotationToString($leftOperand);
        $rightOperand = self::convertScientificNotationToString($rightOperand);

        if (self::checkIsFloat($leftOperand)) {
            throw new \InvalidArgumentException('Left operator has to be an integer');
        }
        if (self::checkIsFloat($rightOperand)) {
            throw new \InvalidArgumentException('Right operator has to be an integer');
        }

        $leftOperandNegative = self::isNegative($leftOperand);
        $rightOperandNegative = self::isNegative($rightOperand);

        $leftOperand = self::dec2bin(self::abs($leftOperand));
        $rightOperand = self::dec2bin(self::abs($rightOperand));

        $maxLength = max(strlen($leftOperand), strlen($rightOperand));

        $leftOperand = self::alignBinLength($leftOperand, $maxLength);
        $rightOperand = self::alignBinLength($rightOperand, $maxLength);

        if ($leftOperandNegative) {
            $leftOperand = self::recalculateNegative($leftOperand);
        }
        if ($rightOperandNegative) {
            $rightOperand = self::recalculateNegative($rightOperand);
        }

        if (self::BIT_OPERATOR_AND === $operator) {
            $result = $leftOperand & $rightOperand;
            $isNegative = ($leftOperandNegative and $rightOperandNegative);
        } elseif (self::BIT_OPERATOR_OR === $operator) {
            $result = $leftOperand | $rightOperand;
            $isNegative = ($leftOperandNegative or $rightOperandNegative);
        } elseif (self::BIT_OPERATOR_XOR === $operator) {
            $result = $leftOperand ^ $rightOperand;
            $isNegative = ($leftOperandNegative xor $rightOperandNegative);
        } else {
            throw new \InvalidArgumentException('Unknown operator');
        }

        if ($isNegative) {
            $result = self::recalculateNegative($result);
        }

        $result = self::bin2dec($result);

        return $isNegative ? '-' . $result : $result;
    }

    /**
     * @param string $number
     * @param int $base
     * @return string
     */
    public static function dec2bin($number, $base = self::MAX_BASE)
    {
        return self::decBaseHelper($base, function ($base) use ($number) {
            $value = '';
            if ('0' === $number) {
                return chr($number);
            }

            while (BC::comp($number, '0') !== BC::COMPARE_EQUAL) {
                $rest = BC::mod($number, $base);
                $number = BC::div($number, $base);
$x = 1;
$callable = function() use ($x) {
    $x = 2; // Not visible in outer scope. If you would like this, how
            // about using a different variable name than $x?
};

$callable();
var_dump($x); // integer(1)
                $value = chr((int)$rest) . $value;
            }

            return $value;
        });
    }

    /**
     * @param int $base
     * @param \Closure $closure
     * @return string
     */
    private static function decBaseHelper($base, \Closure $closure)
    {
        if ($base < 2 || $base > self::MAX_BASE) {
            throw new \InvalidArgumentException('Invalid Base: ' . $base);
        }
        $orgScale = self::getScale();
        self::setScale(0);

        $value = $closure($base);

        self::setScale($orgScale);

        return $value;
    }

    /**
     * @param null|int $scale
     */
    public static function setScale($scale)
    {
        bcscale($scale);
    }

    /**
     * @param int|string $number
     * @return string
     */
    public static function abs($number)
    {
        $number = self::convertScientificNotationToString($number);

        if (self::isNegative($number)) {
            $number = (string)substr($number, 1);
        }

        return self::checkNumber($number);
    }

    /**
     * @param string $string
     * @param int $length
     * @return string
     */
    private static function alignBinLength($string, $length)
    {
        return str_pad($string, $length, self::dec2bin('0'), STR_PAD_LEFT);
    }

    /**
     * @param string $number
     * @return string
     */
    private static function recalculateNegative($number)
    {
        $xor = str_repeat(self::dec2bin(self::MAX_BASE - 1), strlen($number));
        $number ^= $xor;
        for ($i = strlen($number) - 1; $i >= 0; $i--) {
            $byte = ord($number[$i]);
            if (++$byte !== self::MAX_BASE) {
                $number[$i] = chr($byte);
                break;
            }
            $number[$i] = chr(0);
        }

        return $number;
    }

    /**
     * @param string $value
     * @param int $base
     * @return string
     */
    public static function bin2dec($value, $base = self::MAX_BASE)
    {
        return self::decBaseHelper($base, function ($base) use ($value) {
            $size = strlen($value);
            $return = '0';
            for ($i = 0; $i < $size; ++$i) {
                $element = ord($value[$i]);
                $power = BC::pow($base, $size - $i - 1);
                $return = BC::add($return, BC::mul($element, $power));
            }

            return $return;
        });
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @return string
     */
    public static function bitOr($leftOperand, $rightOperand)
    {
        return self::bitOperatorHelper($leftOperand, $rightOperand, self::BIT_OPERATOR_OR);
    }

    /**
     * @param string $leftOperand
     * @param string $rightOperand
     * @return string
     */
    public static function bitXor($leftOperand, $rightOperand)
    {
        return self::bitOperatorHelper($leftOperand, $rightOperand, self::BIT_OPERATOR_XOR);
    }
}


Pull Request — master (#28)

BC F

Complexity

Size/Duplication

Coupling/Cohesion

Test Coverage

Importance

41 Methods

How to fix Duplicated Code Complexity

Duplicated Code

Complex Class

Change not visible in outer-scope

Change visible in outer-scope

krowinski / bcmath-extended

Pull Request — master (#28)

BC F

Complexity

Size/Duplication

Coupling/Cohesion

Test Coverage

Importance

41 Methods

How to fix Duplicated Code Complexity

Duplicated Code

Complex Class

Change not visible in outer-scope

Change visible in outer-scope

Duplication Side-by-Side

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