its-fps-qrcodedata-class.php

<?php
if (!defined('ABSPATH')) {
    return;
}



if( !class_exists('ITS_FPS_QRCodeData') ){
    class ITS_FPS_QRCodeData {

        public function __construct($data){
            $this->data = $data;
        }
    
        public function getDataString(){
            $msg = $this->emvString($this->data);
            $crc = $this->pad(dechex($this->crc16ccitt($msg)),4);
            return $msg . strtoupper($crc);
        }
    
        private function pad($s, $size = 2) {
            while (strlen($s) < $size) {
                $s = "0" . $s;
            }
            return $s;
        }
    
        private function dataObject($id, $value){
            $paddedLength = $this->pad('' . strlen($value), 2);
            return $id . $paddedLength . $value;
        }
    
        private function emvString($data){
            $payloadFormatIndicator = $this->dataObject("00","01");
            $pointOfInitiationMethod = $this->dataObject("01", $data['amount'] === "" ? "11" : "12");
            $guid = $this->dataObject("00","hk.com.hkicl");
            $merchantAccountInformationTemplate = "";
    
            switch($data['account']){
                case "02":
                    $merchantAccountInformationTemplate = $this->dataObject("02", $data['fps_id']);
                    break;
                case "03":
                    $merchantAccountInformationTemplate = $this->dataObject("01", $data['bank_code']) . $this->dataObject("03", $data['mobile']);
                    break;
                case "04":
                    $merchantAccountInformationTemplate = $this->dataObject("01", $data['bank_code']) . $this->dataObject("04", strtoupper($data['email']));
                    break;
                default:
                    return null;
            }
    
            $merchantAccountInformation = $this->dataObject("26", $guid . $merchantAccountInformationTemplate);
            $merchantCategoryCode = $this->dataObject("52", $data['mcc']);
            $transactionCurrency = $this->dataObject("53", $data['currency']);
            $countryCode = $this->dataObject("58", "HK");
            $merchantName = $this->dataObject("59","NA");
            $merchantCity = $this->dataObject("60","HK");
            $transactionAmount = $data['amount'] === '' ? "" : $this->dataObject("54",$data['amount']);
            $reference = $data['reference'] === '' ? "" : $this->dataObject("05",$data['reference']);
            $additionalDataTemplate = $reference === "" ? "" : $this->dataObject("62", $reference);
    
            $msg = "";
    
            $msg .= $payloadFormatIndicator;
            $msg .= $pointOfInitiationMethod;
            $msg .= $merchantAccountInformation;
            $msg .= $merchantCategoryCode;
            $msg .= $transactionCurrency;
            $msg .= $countryCode;
            $msg .= $merchantName;
            $msg .= $merchantCity;
            $msg .= $transactionAmount;
            $msg .= $additionalDataTemplate;
            $msg .= "6304";
    
            return $msg;
    
    
        }
    
        private function crc16ccitt($s){
            $crcTable = [
                0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5,
                0x60c6, 0x70e7, 0x8108, 0x9129, 0xa14a, 0xb16b,
                0xc18c, 0xd1ad, 0xe1ce, 0xf1ef, 0x1231, 0x0210,
                0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
                0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c,
                0xf3ff, 0xe3de, 0x2462, 0x3443, 0x0420, 0x1401,
                0x64e6, 0x74c7, 0x44a4, 0x5485, 0xa56a, 0xb54b,
                0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
                0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6,
                0x5695, 0x46b4, 0xb75b, 0xa77a, 0x9719, 0x8738,
                0xf7df, 0xe7fe, 0xd79d, 0xc7bc, 0x48c4, 0x58e5,
                0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
                0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969,
                0xa90a, 0xb92b, 0x5af5, 0x4ad4, 0x7ab7, 0x6a96,
                0x1a71, 0x0a50, 0x3a33, 0x2a12, 0xdbfd, 0xcbdc,
                0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
                0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03,
                0x0c60, 0x1c41, 0xedae, 0xfd8f, 0xcdec, 0xddcd,
                0xad2a, 0xbd0b, 0x8d68, 0x9d49, 0x7e97, 0x6eb6,
                0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
                0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a,
                0x9f59, 0x8f78, 0x9188, 0x81a9, 0xb1ca, 0xa1eb,
                0xd10c, 0xc12d, 0xf14e, 0xe16f, 0x1080, 0x00a1,
                0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
                0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c,
                0xe37f, 0xf35e, 0x02b1, 0x1290, 0x22f3, 0x32d2,
                0x4235, 0x5214, 0x6277, 0x7256, 0xb5ea, 0xa5cb,
                0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
                0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447,
                0x5424, 0x4405, 0xa7db, 0xb7fa, 0x8799, 0x97b8,
                0xe75f, 0xf77e, 0xc71d, 0xd73c, 0x26d3, 0x36f2,
                0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
                0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9,
                0xb98a, 0xa9ab, 0x5844, 0x4865, 0x7806, 0x6827,
                0x18c0, 0x08e1, 0x3882, 0x28a3, 0xcb7d, 0xdb5c,
                0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
                0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0,
                0x2ab3, 0x3a92, 0xfd2e, 0xed0f, 0xdd6c, 0xcd4d,
                0xbdaa, 0xad8b, 0x9de8, 0x8dc9, 0x7c26, 0x6c07,
                0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
                0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba,
                0x8fd9, 0x9ff8, 0x6e17, 0x7e36, 0x4e55, 0x5e74,
                0x2e93, 0x3eb2, 0x0ed1, 0x1ef0
            ];
    
            $crc = 0xFFFF;
            $j = null;
    
            $slen = strlen($s);
            for ($i=0; $i < $slen; $i++) { 
                $c = ord(substr($s, $i));
                if( $c > 255 ){
                    echo "Range error";
                    exit;
                }
                $j = ($c ^ ($crc >> 8)) & 0xFF;
                $crc = $crcTable[$j] ^ ($crc << 8);
            }
    
            return (($crc ^ 0) & 0xFFFF);
    
        }
    }
}