<?php

/**
 * @package         EngageBox
 * @version         4.0.0 Pro
 *
 * @author          Tassos Marinos <info@tassos.gr>
 * @link            http://www.tassos.gr
 * @copyright       Copyright © 2020 Tassos Marinos All Rights Reserved
 * @license         GNU GPLv3 <http://www.gnu.org/licenses/gpl.html> or later
 */

defined('_JEXEC') or die;

if (!function_exists('bcadd'))
{
	function bcadd($Num1,$Num2,$Scale=null)
	{
		// check if they're valid positive numbers, extract the whole numbers and decimals
		if(!preg_match("/^\+?(\d+)(\.\d+)?$/",$Num1,$Tmp1)||
			!preg_match("/^\+?(\d+)(\.\d+)?$/",$Num2,$Tmp2)) return('0');

		// this is where the result is stored
		$Output=array();

		// remove ending zeroes from decimals and remove point
		$Dec1=isset($Tmp1[2])?rtrim(substr($Tmp1[2],1),'0'):'';
		$Dec2=isset($Tmp2[2])?rtrim(substr($Tmp2[2],1),'0'):'';

		// calculate the longest length of decimals
		$DLen=max(strlen($Dec1),strlen($Dec2));

		// if $Scale is null, automatically set it to the amount of decimal places for accuracy
		if($Scale==null) $Scale=$DLen;

		// remove leading zeroes and reverse the whole numbers, then append padded decimals on the end
		$Num1=strrev(ltrim($Tmp1[1],'0').str_pad($Dec1,$DLen,'0'));
		$Num2=strrev(ltrim($Tmp2[1],'0').str_pad($Dec2,$DLen,'0'));

		// calculate the longest length we need to process
		$MLen=max(strlen($Num1),strlen($Num2));

		// pad the two numbers so they are of equal length (both equal to $MLen)
		$Num1=str_pad($Num1,$MLen,'0');
		$Num2=str_pad($Num2,$MLen,'0');

		// process each digit, keep the ones, carry the tens (remainders)
		for($i=0;$i<$MLen;$i++) {
			$Sum=((int)$Num1{$i}+(int)$Num2{$i});
			if(isset($Output[$i])) $Sum+=$Output[$i];
			$Output[$i]=$Sum%10;
			if($Sum>9) $Output[$i+1]=1;
		}

		// convert the array to string and reverse it
		$Output=strrev(implode($Output));

		// substring the decimal digits from the result, pad if necessary (if $Scale > amount of actual decimals)
		// next, since actual zero values can cause a problem with the substring values, if so, just simply give '0'
		// next, append the decimal value, if $Scale is defined, and return result
		$Decimal=str_pad(substr($Output,-$DLen,$Scale),$Scale,'0');
		$Output=(($MLen-$DLen<1)?'0':substr($Output,0,-$DLen));
		$Output.=(($Scale>0)?".{$Decimal}":'');
		return($Output);
	}
}

if (!function_exists('bcmul'))
{
	function bcmul($Num1='0',$Num2='0') {
		// check if they're both plain numbers
		if(!preg_match("/^\d+$/",$Num1)||!preg_match("/^\d+$/",$Num2)) return(0);

		// remove zeroes from beginning of numbers
		for($i=0;$i<strlen($Num1);$i++) if(@$Num1{$i}!='0') {$Num1=substr($Num1,$i);break;}
		for($i=0;$i<strlen($Num2);$i++) if(@$Num2{$i}!='0') {$Num2=substr($Num2,$i);break;}

		// get both number lengths
		$Len1=strlen($Num1);
		$Len2=strlen($Num2);

		// $Rema is for storing the calculated numbers and $Rema2 is for carrying the remainders
		$Rema=$Rema2=array();

		// we start by making a $Len1 by $Len2 table (array)
		for($y=$i=0;$y<$Len1;$y++)
			for($x=0;$x<$Len2;$x++)
				// we use the classic lattice method for calculating the multiplication..
				// this will multiply each number in $Num1 with each number in $Num2 and store it accordingly
				@$Rema[$i++%$Len2].=sprintf('%02d',(int)$Num1{$y}*(int)$Num2{$x});

		// cycle through each stored number
		for($y=0;$y<$Len2;$y++)
			for($x=0;$x<$Len1*2;$x++)
				// add up the numbers in the diagonal fashion the lattice method uses
				@$Rema2[Floor(($x-1)/2)+1+$y]+=(int)$Rema[$y]{$x};

		// reverse the results around
		$Rema2=array_reverse($Rema2);

		// cycle through all the results again
		for($i=0;$i<count($Rema2);$i++) {
			// reverse this item, split, keep the first digit, spread the other digits down the array
			$Rema3=str_split(strrev($Rema2[$i]));
			for($o=0;$o<count($Rema3);$o++)
				if($o==0) @$Rema2[$i+$o]=$Rema3[$o];
				else @$Rema2[$i+$o]+=$Rema3[$o];
		}
		// implode $Rema2 so it's a string and reverse it, this is the result!
		$Rema2=strrev(implode($Rema2));

		// just to make sure, we delete the zeros from the beginning of the result and return
		while(strlen($Rema2)>1&&$Rema2{0}=='0') $Rema2=substr($Rema2,1);

		return($Rema2);
	}
}

if (!function_exists('bcpow'))
{
	function bcpow($num, $power)
	{
		$answer = "1";

		while ($power)
		{
			$answer = bcmul($answer, $num, 100);
			$power--;
		}
		return rtrim($answer, '0.');
	}
}