<?php
class Crypt {
	var $keys;
	
	function crypt_key($ckey){
		$this->keys = array();
		
		$c_key = base64_encode(sha1(md5($ckey)));
		$c_key = substr($c_key, 0, round(ord($ckey{0})/5));
		
		$c2_key = base64_encode(md5(sha1($ckey)));
		$last = strlen($ckey) - 1;
		$c2_key = substr($c2_key, 1, round(ord($ckey{$last})/7));
		
		$c3_key = base64_encode(sha1(md5($c_key).md5($c2_key)));
		$mid = round($last/2);
		$c3_key = substr($c3_key, 1, round(ord($ckey{$mid})/9));
		
		$c_key = $c_key.$c2_key.$c3_key;
		$c_key = base64_encode($c_key);
		
		for($i = 0; $i < strlen($c_key); $i++){
			$this->keys[] = $c_key[$i];
		}
	}
	
	function encrypt($string){
		$string = base64_encode($string);
		$keys = $this->keys;
		for($i = 0; $i < strlen($string); $i++){
		  if(count($keys)>0){	
				$id = $i % count($keys);
				$ord = ord($string{$i});
				$ord = $ord OR ord($keys[$id]);
				$id++;
				$ord = $ord AND ord($keys[$id]);
				$id++;
				$ord = $ord XOR ord($keys[$id]);
				$id++;
				$ord = $ord + ord($keys[$id]);
				$string{$i} = chr($ord);
		  }
		  else{
		    $id = $i % 1;
				$ord = ord($string{$i});
				$ord = $ord OR ord($keys[$id]);
				$id++;
				$ord = $ord AND ord($keys[$id]);
				$id++;
				$ord = $ord XOR ord($keys[$id]);
				$id++;
				$ord = $ord + ord($keys[$id]);
				$string{$i} = chr($ord);
		  }	
		}
		return base64_encode($string);
	}
	
	function decrypt($string){
		$string = base64_decode($string);
		$keys = $this->keys;
		for($i = 0; $i < strlen($string); $i++){
		  if(count($keys)>0)	{
				$id = $i % count($keys);
				$ord = ord($string{$i});
				$ord = $ord XOR ord($keys[$id]);
				$id++;
				$ord = $ord AND ord($keys[$id]);
				$id++;
				$ord = $ord OR ord($keys[$id]);
				$id++;
				$ord = $ord - ord($keys[$id]);
				$string{$i} = chr($ord);
		  }
		  else{
		    $id = $i % 1;
				$ord = ord($string{$i});
				$ord = $ord XOR ord($keys[$id]);
				$id++;
				$ord = $ord AND ord($keys[$id]);
				$id++;
				$ord = $ord OR ord($keys[$id]);
				$id++;
				$ord = $ord - ord($keys[$id]);
				$string{$i} = chr($ord);
		  }	
		}
		return base64_decode($string);
	}
}
?>