Class version of PHP Bitcoin Address Validator

<?php
// From http://pastebin.com/vmRQC7ha
//hex input must be in uppercase, with no leading 0x

class BitCoinValidator {

    public $addressversion = "00"; //this is a hex byte

    public function __construct($testnet = false)
    {
        $this->addressversion = ($testnet) ? "6F" : "00"; //TestNet vs ProductionNet
    }
    public function decodeHex($hex)
    {
        $hex=strtoupper($hex);
        $chars="0123456789ABCDEF";
        $return="0";
        for($i=0;$i<strlen($hex);$i++)
        {
            $current=(string)strpos($chars,$hex[$i]);
            $return=(string)bcmul($return,"16",0);
            $return=(string)bcadd($return,$current,0);
        }
        return $return;
    }

    public function encodeHex($dec)
    {
        $chars="0123456789ABCDEF";
        $return="";
        while (bccomp($dec,0)==1)
        {
            $dv=(string)bcdiv($dec,"16",0);
            $rem=(integer)bcmod($dec,"16");
            $dec=$dv;
            $return=$return.$chars[$rem];
        }
        return strrev($return);
    }

    public function decodeBase58($base58)
    {
        $origbase58=$base58;

        $chars="123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";
        $return="0";
        for($i=0;$i<strlen($base58);$i++)
        {
            $current=(string)strpos($chars,$base58[$i]);
            $return=(string)bcmul($return,"58",0);
            $return=(string)bcadd($return,$current,0);
        }

        $return=$this->encodeHex($return);

        //leading zeros
        for($i=0;$i<strlen($origbase58)&&$origbase58[$i]=="1";$i++)
        {
            $return="00".$return;
        }

        if(strlen($return)%2!=0)
        {
            $return="0".$return;
        }

        return $return;
    }

    public function encodeBase58($hex)
    {
        if(strlen($hex)%2!=0)
        {
            die("encodeBase58: uneven number of hex characters");
        }
        $orighex=$hex;

        $chars="123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";
        $hex=$this->decodeHex($hex);
        $return="";
        while (bccomp($hex,0)==1)
        {
            $dv=(string)bcdiv($hex,"58",0);
            $rem=(integer)bcmod($hex,"58");
            $hex=$dv;
            $return=$return.$chars[$rem];
        }
        $return=strrev($return);

        //leading zeros
        for($i=0;$i<strlen($orighex)&&substr($orighex,$i,2)=="00";$i+=2)
        {
            $return="1".$return;
        }

        return $return;
    }

    public function hash160ToAddress($hash160)
    {
        $hash160=$this->addressversion.$hash160;
        $check=pack("H*" , $hash160);
        $check=hash("sha256",hash("sha256",$check,true));
        $check=substr($check,0,8);
        $hash160=strtoupper($hash160.$check);
        return $this->encodeBase58($hash160);
    }

    public function addressToHash160($addr)
    {
        $addr=$this->decodeBase58($addr);
        $addr=substr($addr,2,strlen($addr)-10);
        return $addr;
    }

    public function _checkAddress($addr)
    {
        $addr=$this->decodeBase58($addr);
        if(strlen($addr)!=50)
        {
            return false;
        }
        $version=substr($addr,0,2);
        if(hexdec($version)>hexdec($this->addressversion))
        {
            return false;
        }
        $check=substr($addr,0,strlen($addr)-8);
        $check=pack("H*" , $check);
        $check=strtoupper(hash("sha256",hash("sha256",$check,true)));
        $check=substr($check,0,8);
        return $check==substr($addr,strlen($addr)-8);
    }

    public function hash160($data)
    {
        $data=pack("H*" , $data);
        return strtoupper(hash("ripemd160",hash("sha256",$data,true)));
    }

    public function pubKeyToAddress($pubkey)
    {
        return $this->hash160ToAddress($this->hash160($pubkey));
    }

    public function remove0x($string)
    {
        if(substr($string,0,2)=="0x"||substr($string,0,2)=="0X")
        {
            $string=substr($string,2);
        }
        return $string;
    }
    public static function checkAddress($addr, $testnet = false)
    {
        $obj = new self($testnet);
        return $obj->_checkAddress($addr);
    }
}