<?php
declare(strict_types=1);
/*
* The MIT License (MIT)
*
* Copyright (c) 2014-2021 Spomky-Labs
*
* This software may be modified and distributed under the terms
* of the MIT license. See the LICENSE file for details.
*/
namespace Cose;
use Brick\Math\BigInteger as BrickBigInteger;
use function chr;
use function hex2bin;
use InvalidArgumentException;
use function unpack;
/**
* @internal
*/
class BigInteger
{
/**
* Holds the BigInteger's value.
*
* @var BrickBigInteger
*/
private $value;
private function __construct(BrickBigInteger $value)
{
$this->value = $value;
}
public static function createFromBinaryString(string $value): self
{
$res = unpack('H*', $value);
if (false === $res) {
throw new InvalidArgumentException('Unable to convert the data from binary');
}
$data = current($res);
return new self(BrickBigInteger::fromBase($data, 16));
}
public static function createFromDecimal(int $value): self
{
return new self(BrickBigInteger::of($value));
}
/**
* Converts a BigInteger to a binary string.
*/
public function toBytes(): string
{
if ($this->value->isEqualTo(BrickBigInteger::zero())) {
return '';
}
$temp = $this->value->toBase(16);
$temp = 0 !== (mb_strlen($temp, '8bit') & 1) ? '0'.$temp : $temp;
$temp = hex2bin($temp);
if (false === $temp) {
throw new InvalidArgumentException('Unable to convert the data into binary');
}
return ltrim($temp, chr(0));
}
/**
* Adds two BigIntegers.
*
* @param BigInteger $y
*
* @return BigInteger
*/
public function add(self $y): self
{
$value = $this->value->plus($y->value);
return new self($value);
}
/**
* Subtracts two BigIntegers.
*
* @param BigInteger $y
*
* @return BigInteger
*/
public function subtract(self $y): self
{
$value = $this->value->minus($y->value);
return new self($value);
}
/**
* Multiplies two BigIntegers.
*
* @param BigInteger $x
*
* @return BigInteger
*/
public function multiply(self $x): self
{
$value = $this->value->multipliedBy($x->value);
return new self($value);
}
/**
* Performs modular exponentiation.
*
* @param BigInteger $e
* @param BigInteger $n
*
* @return BigInteger
*/
public function modPow(self $e, self $n): self
{
$value = $this->value->modPow($e->value, $n->value);
return new self($value);
}
/**
* Performs modular exponentiation.
*
* @param BigInteger $d
*
* @return BigInteger
*/
public function mod(self $d): self
{
$value = $this->value->mod($d->value);
return new self($value);
}
/**
* Compares two numbers.
*
* @param BigInteger $y
*/
public function compare(self $y): int
{
return $this->value->compareTo($y->value);
}
}