Del\Phi\Fraction

Complexity

Total Complexity

39

Size/Duplication

Total Lines	252
Duplicated Lines	0 %

Coupling/Cohesion

Components	1
Dependencies	1

Test Coverage

Coverage

100%

Importance

Changes	6
Bugs	1	Features	0

23 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	0	7	1
A	getWhole()	0	4	1
A	setWhole()	0	6	1
A	getNumerator()	0	4	1
A	setNumerator()	0	6	1
A	getDenominator()	0	4	1
A	setDenominator()	0	6	1
A	refactor()	0	10	3
A	shouldRefactorWhole()	0	5	2
A	shouldRefactorFraction()	0	5	2
A	refactorWhole()	0	8	2
A	refactorFraction()	0	6	1
A	getGreatestCommonDenominator()	0	14	1
A	getFactors()	0	11	3
A	isNegative()	0	4	1
A	setNegative()	0	5	1
A	isInteger()	0	4	1
A	__toString()	0	9	1
A	getStringWhole()	0	4	2
A	getStringFraction()	0	4	3
B	formatString()	0	6	5
A	toDecimal()	0	10	2
A	throwExceptionIfNegative()	0	6	2

<?php

namespace Del\Phi;

use Del\Phi\Exception\PhiException;
use InvalidArgumentException;

class Fraction
{
    /** @var int $whole */
    private $whole;

    /** @var int $numerator */
    private $numerator;

    /** @var int $denominator */
    private $denominator;

    /** @var bool $negative */
    private $negative;

    public function __construct($whole = 0, $numerator = 0, $denominator = 1)
    {
        $this->whole = $whole;
        $this->numerator = $numerator;
        $this->denominator = $denominator;
        $this->negative = false;
    }

    /**
     * @return int
     */
    public function getWhole()
    {
        return $this->whole;
    }

    /**
     * @param int $whole
     * @return Fraction
     */
    public function setWhole($whole)
    {
        $this->throwExceptionIfNegative($whole);
        $this->whole = $whole;
        return $this;
    }

    /**
     * @return int
     */
    public function getNumerator()
    {
        return $this->numerator;
    }

    /**
     * @param int $numerator
     * @return Fraction
     */
    public function setNumerator($numerator)
    {
        $this->throwExceptionIfNegative($numerator);
        $this->numerator = $numerator;
        return $this;
    }

    /**
     * @return int
     */
    public function getDenominator()
    {
        return $this->denominator;
    }

    /**
     * @param int $denominator
     * @return Fraction
     */
    public function setDenominator($denominator)
    {
        $this->throwExceptionIfNegative($denominator);
        $this->denominator = $denominator;
        return $this;
    }

    private function refactor()
    {
        // 9/8 would become 1 1/8 for instance
        if ($this->shouldRefactorWhole()) {
            $this->refactorWhole();
        }
        if ($this->shouldRefactorFraction()) {
            $this->refactorFraction();
        }
    }

    /**
     * @return bool
     */
    private function shouldRefactorWhole()
    {
        return $this->numerator >= $this->denominator
            && $this->denominator > 0;
    }

    /**
     * @return bool
     */
    private function shouldRefactorFraction()
    {
        return $this->numerator > 0
            && $this->denominator > 0;
    }

    private function refactorWhole()
    {
        // decrement $x and the numerator by the denominator each loop, and add to the whole
        for ($x = $this->numerator; $x >= $this->denominator; $x = $x - $this->denominator) {
            $this->whole ++;
            $this->numerator -= $this->denominator;
        }
    }

    private function refactorFraction()
    {
        $gcd = $this->getGreatestCommonDenominator($this->numerator, $this->denominator);
        $this->numerator = $this->numerator / $gcd;
        $this->denominator = $this->denominator / $gcd;
    }

    /**
     * @param int $x
     * @param int $y
     * @return int
     */
    private function getGreatestCommonDenominator($x, $y)
    {
        // first get the common denominators of both numerator and denominator
        $factorsX = $this->getFactors($x);
        $factorsY = $this->getFactors($y);

        // common denominators will be in both arrays, so get the intersect
        $commonDenominators = array_intersect($factorsX, $factorsY);

        // greatest common denominator is the highest number (last in the array)
        $gcd = array_pop($commonDenominators);

        return $gcd;
    }

    /**
     * @param int $num
     * @return array The common denominators of $num
     */
    private function getFactors($num)
    {
        $factors = [];
        // get factors of the numerator
        for ($x = 1; $x <= $num; $x ++) {
            if ($num % $x == 0) {
                $factors[] = $x;
            }
        }
        return $factors;
    }

    /**
     * @return bool
     */
    public function isNegative()
    {
        return $this->negative;
    }

    /**
     * @param bool $negative
     * @return Fraction
     */
    public function setNegative($negative)
    {
        $this->negative = $negative;
        return $this;
    }

    /**
     * @return bool
     */
    public function isInteger()
    {
        return $this->numerator % $this->denominator == 0;
    }

    /**
     * @return string
     */
    public function __toString()
    {
        $this->refactor();

        // if the whole is 0, don't display it
        $whole = $this->getStringWhole();
        $fraction = $this->getStringFraction();
        return $this->formatString($whole, $fraction);
    }

    /**
     * @return string
     */
    private function getStringWhole()
    {
        return $this->whole == 0 ? '' : (string) $this->whole;
    }

    /**
     * @return string
     */
    private function getStringFraction()
    {
        return $this->numerator > 0 && $this->denominator > 0 ? $this->numerator.'/'.$this->denominator : '';;
    }

    /**
     * @param string $whole
     * @param string $fraction
     * @return string
     */
    private function formatString($whole, $fraction)
    {
        $space = ($whole && $fraction) ? ' ' : '';
        $negative = $this->isNegative() ? '-' : '';
        return empty($negative.$whole.$space.$fraction) ? '0' : $negative.$whole.$space.$fraction;
    }

    /**
     * @return float
     */
    public function toDecimal()
    {
        /*
         * a divide symbol. so this is broken and will need refactoring to be accurate. ;-)
         */
        $decimal = $this->numerator / $this->denominator;
        $number =  $this->whole + $decimal;
        $number = $this->isNegative() ? $number - $number - $number : $number;
        return $number;
    }

    /**
     * @param $num
     * @throws PhiException
     */
    public function throwExceptionIfNegative($num)
    {
        if ($num < 0) {
            throw new PhiException(PhiException::ERROR_NEGATIVE_NUMBER);
        }
    }
}