WordPress plugin to progressively obfuscate text like MAKEbook.io

obfuscate.php

/*
--PIETZ OBFUSCATE CODE--
2019-06-01
from MAKEbook.io

Instructions:
1) put this in your functions.php file
2) add this to the post you want to obfuscate, on top
3) [obfuscate]
4) to start obfuscating, add a HTML code or HTML block with <start></start>
5) to end obfuscating, add a HTML code or HTML block with <stop></stop>
6) it starts obfuscating from character 30,000, to change that, find this and change 30000 to something more or less: if($y<30000 ||
7) .....
8) PROFIT!                                                                                                                                  


MIT licensed, no liability: u break ur site, ur problem not mine love ya <3

*/

function obfuscate() {
	if(!is_single()) return;

	ob_start("progressivelyObfuscateText");
}
add_shortcode('obfuscate', 'obfuscate');

$obfuscating='off';
function progressivelyObfuscateText($text) {

	$constant=0;
	$exponent=2;
	$multiplier=10;

	srand('1232993237');

	$chars=str_split($text);

	$alphabet='abcdefghijklmnopqrstuvwxyz';
	$alphabet=str_split($alphabet);

	$vowels='aeiouy';
	$vowels=str_split($vowels);

	$consonants='bcdfghjklmnpqrstvwxzw';
	$consonants=str_split($consonants);

	$obfuscatedText='';
	$i=0;
	$y=-1;
	$insideHTMLTag=false;
	foreach($chars as $char) {
		$i++;
		$y++;
		
		$progress=$i/1500*$multiplier + pow($i/1500,$exponent) -$constant;
		if($chars[$y-3].$chars[$y-2].$chars[$y-1].$chars[$y]=='<h1>') {
			// reset progress if we find <h1> because it means new chapter
			// so we progressively obfuscate again
			$i=0;
		}
		if($chars[$y-3].$chars[$y-2].$chars[$y-1].$chars[$y]=='<h2>') {
			// reset progress if we find <h2> because it means new head
			// so we progressively obfuscate again
			$i=0;
		}

		if($chars[$y-3].$chars[$y-2].$chars[$y-1].$chars[$y]=='<h3>') {
			// reset progress if we find <h3> because it means new head
			// so we progressively obfuscate again
			$i=0;
		}
		if($chars[$y-5].$chars[$y-4].$chars[$y-3].$chars[$y-2].$chars[$y-1].$chars[$y]=='<stop>') {
			// stop altogether with obfuscating if we get stop code
			$i=0;
			$obfuscating='off';
			$obfuscatedText.=$char;
			continue;
		}
		if($chars[$y-6].$chars[$y-5].$chars[$y-4].$chars[$y-3].$chars[$y-2].$chars[$y-1].$chars[$y]=='<start>') {
			$obfuscating='on';
		}
		if($obfuscating=='off') {
			$obfuscatedText.=$char;
			continue;
		}
		if($chars[$y-2].$chars[$y-1].$chars[$y]=='<b>') {
			$insideBoldTag=true;
			$obfuscatedText.=$char;
			// $obfuscatedText.='<hr>entering<hr>';
			continue;
		}
		if($chars[$y-3].$chars[$y-2].$chars[$y-1].$chars[$y]=='</b>') {
			$insideBoldTag=false;
			$obfuscatedText.=$char;
			// $obfuscatedText.='<hr>exiting<hr>';
			continue;
		}
		if($char=='<') {
			$insideHTMLTag=true;
			$obfuscatedText.=$char;
			continue;
		}
		if($char=='>') {
			$insideHTMLTag=false;
			$obfuscatedText.=$char;
			continue;
		}
		if($insideHTMLTag || $insideHeaderTag || $insideBoldTag || $insideLinkTag) {
			$obfuscatedText.=$char;
			continue;
		}
		if($y<30000 || !ctype_alnum($char) || $char==' ' || $char=='"' || $char=='$' || $char=='/' || $char==',' || $char=='http://'  || $char=="'"  || $char=="\n" || $char=="\t" || $char=="\r") {
			$obfuscatedText.=$char;
			continue;
		}
		if(floor(1-rand(0,$progress))==1) {
			$obfuscatedText.=$char;
			continue;
		}
		if(in_array($char,$consonants)) $char=$consonants[array_rand($consonants)];
		if(in_array($char,$vowels)) $char=$vowels[array_rand($vowels)];
		
		$obfuscatedText.=$char;
	}

	return $obfuscatedText;
}