<?php

################### https://www.dotpay.pl/developer/doc/api_payment/   ######################################################################
#
#    Exemplary function (PHP) generating  the correct payment redirection (POST / GET) to Dotpay payment api with parametr 'chk' (checksum).
#    You enter the payment data in the parameter: $ParametersArray.
#
#
#    PayPro S.A. 
#    Tech Customer Service: tech@dotpay.pl
#       Date: 2020-05-19
#
##############################################################################################################################################


/** ---------  BASE CONFIG  ---------  **/

// Your Dotpay ID shop (6 digits)
$DotpayId = "123456";

// PIN for Your Dotpay ID (copy this from your dotpay panel carefully, without space)
$DotpayPin = "MyDotpayPIN000000j7yytSgMPXlg200";

// Dotpay Environment, available: "test" or "production"
$Environment = "test";

//Redirection method: POST or GET ; recommended method is "POST"
$RedirectionMethod = "POST";

// Auto submit form: available: true or false:
// If true - you do not need to do a click to the form. Forwarding to the API will be automatically
$autosubmit = true;

/**  ---------  end config  ---------  **/



// ** -----------------------   SAMPLE DATA ------------------------- **/

/*  ## SAMPLE PAYMENT DATA IN ##  */
// Note! You can use more parameters if You need
// You must give at least: 'amount', 'currency', 'description' (and of course ID and PIN in the configuration of this script)
// see more: https://www.dotpay.pl/developer/doc/api_payment/en/index.html#tabela-1-podstawowe-parametry-przesylane-do-serwisu-dotpay
// and: https://www.dotpay.pl/developer/doc/api_payment/en/index.html#tabela-2-dodatkowe-parametry-przesylane-do-serwisu-dotpay


/*  Important!

    All values should be string.
    If you use a variable here, put a declaration (string) before the value.
    Other values should be enclosed in quotation marks, especially numerical ones.
*/

$ParametersArray = array(
    "id" => (string) $DotpayId,
    "api_version" => "next",
    "amount" => "345.12",
    "currency" => "PLN",
    "description" => "Order no. 8765GfdC6",
    "url" => "https://www.example.com/thanks_page.php",
    "type" => "0",
    "urlc" => "https://www.example.com/urlc_receiver.php",
    "control" => "8765GfdC6-dsgfdg-2342235",
    "firstname" => "Jan",
    "lastname" => "Nowak",
    "email" => "jan.nowak@example.com"
);

// ** -----------------------   SAMPLE DATA  end ------------------------- **/


// if you do not know what configuration is on your account, add this parameter safely

if(!(isset($ParametersArray['api_version']) && $ParametersArray['api_version'] == "next")){
	$ParametersArray['api_version'] = "next";
}


## function: counts the checksum from the defined array of all parameters

function GenerateChk($DotpayPin, $ParametersArray)
{
    
    //sorting the parameter list
    ksort($ParametersArray);
    
    // Display the semicolon separated list
    $paramList = implode(';', array_keys($ParametersArray));
    
    //adding the parameter 'paramList' with sorted list of parameters to the array
    $ParametersArray['paramsList'] = $paramList;
    
    //re-sorting the parameter list
    ksort($ParametersArray);
    
    //json encoding  
    $json = json_encode($ParametersArray, JSON_UNESCAPED_SLASHES);
    
    
    return hash_hmac('sha256', $json, $DotpayPin, false);
    
}


## Function: Generate simple FORM to DOTPAY

function GenerateChkDotpayRedirection($DotpayPin, $Environment, $RedirectionMethod, $ParametersArray, $next_chk, $autosubmit)
{       
    
    if ($Environment == 'production') {
        $EnvironmentAddress = 'https://ssl.dotpay.pl/t2/';
    } elseif ($Environment == 'test') {
        $EnvironmentAddress = 'https://ssl.dotpay.pl/test_payment/';
    }
    
    
    
    if ($RedirectionMethod == 'POST') {
        $RedirectionCode = '<form action="' . $EnvironmentAddress . '" method="POST" id="dotpay_redirection_form" accept-charset="UTF-8">' . PHP_EOL;
        
        foreach ($ParametersArray as $key => $value) {
            $RedirectionCode .= "\t" . '<input name="' . $key . '" value="' . $value . '" type="hidden"/>' . PHP_EOL;
        }
        $RedirectionCode .= "\t" . '<input name="chk" value="' . $next_chk . '" type="hidden"/>' . PHP_EOL;
        $RedirectionCode .= '</form>' . PHP_EOL . '<button id="dotpay_redirection_button" type="submit" form="dotpay_redirection_form" value="Submit">Confirm and Pay</button>' . PHP_EOL;
        
        //auto submit form
        if ($autosubmit == true) {
            $RedirectionCode .= "<script type=\"text/javascript\">setTimeout(function(){document.getElementById('dotpay_redirection_form').submit();}, 10);</script>";
        }
        
        return $RedirectionCode;
        
    } elseif ($RedirectionMethod == 'GET') {
        $RedirectionCode = $EnvironmentAddress . '?';
        
        foreach ($ParametersArray as $key => $value) {
            $RedirectionCode .= $key . '=' . rawurlencode($value) . '&';
        }
        
        $RedirectionCode .= 'chk=' . $next_chk;
        
        return '<a href="' . $RedirectionCode . '">Link to Pay</a>';
    } else {
        return 'configuration error';
        
    }
        
}


####  

// Calculate checksum for 'chk' parameter:

$next_chk = GenerateChk($DotpayPin, $ParametersArray);

/*   
     Print the form according to the settings: 
     get form (POST method) or payment link (GET method) 
     ("account PIN","[test|production]","[POST|GET]","payment data","chk_value","[true|false]")

*/

echo GenerateChkDotpayRedirection($DotpayPin, $Environment, $RedirectionMethod, $ParametersArray, $next_chk, $autosubmit);

?>