Payment adapter custom for Boxbilling using Paylane gateway

Paylane.php

<?php
/**
 * filepath: __DIR__/bb-library/Payment/Adapter/Paylane.php
 */
class Payment_Adapter_Paylane implements \Box\InjectionAwareInterface
{
    private $config = array();
    protected $di;

    public function setDi($di) 
    {
        $this->di = $di;
    }

    public function getDi() 
    {
        return $this->di;
    }

    public function __construct($config) 
    {
        if(!function_exists('curl_exec')) {
            throw new Payment_Exception('PHP Curl extension not enabled');
        }
    
        if(!isset($this->config['merchant_id'])) {
            throw new Payment_Exception('Payment gateway "PayLane" is not configured properly. Please update configuration parameter "PayLane Merchant Id" at "Configuration -> Payments".');
        }
    
        if(!isset($this->config['salt'])) {
            throw new Payment_Exception('Payment gateway "PayLane" is not configured properly. Please update configuration parameter "PayLane Has Salt" at "Configuration -> Payments".');
        }

        if (!isset($config['test_mode'])) $config['test_mode'] = false;
        $this->config = $config;
    }

    public static function getConfig() 
    {
        return array(
            'can_load_in_iframe'   =>  true,
            'supports_one_time_payments'   =>  true,
            'supports_subscriptions'       =>  false,
            'description'     =>  'Enter your Paylane data to start accepting payments by Paylane.',
            'form'  => array(
                'merchant_id' => array('text', array(
                      'label' => 'Paylane Merchant ID',
                    ),
                ),
                'salt' => array('text', array(
                      'label' => 'Paylane Hash salt',
                    ),
                ),
          ),
        );
    }

    /**
     * Generate payment text
     * 
     * @param Api_Admin $api_admin
     * @param int $invoice_id
     * @param bool $subscription
     * 
     * @since BoxBilling v2.9.15
     * 
     * @return string - html form with auto submit javascript
     */
    public function getHtml($api_admin, $invoice_id, $subscription)
    {
        $invoice = $api_admin->invoice_get(array('id'=>$invoice_id));

        if($subscription) {
            $data = $this->getSubscriptionFields($invoice);
        } else {
            $data = $this->getOneTimePaymentFields($invoice);
        }

        $url = $this->serviceUrl();
        return $this->_generateForm($url, $data);
    }

    public function processTransaction($api_admin, $id, $data, $gateway_id)
    {
        $ipn = $data['post'];
        if($this->config['test_mode']) {
            return json_encode($ipn);
        }

        if ($this->isIpnDuplicate($ipn)){
            throw new Payment_Exception('IPN is duplicate');
        }

        $tx = $api_admin->invoice_transaction_get(array('id'=>$id));
        if(!$tx['invoice_id']) {
            $api_admin->invoice_transaction_update(array('id'=>$id, 'invoice_id'=>$data['get']['bb_invoice_id']));
        }
    
        if(!$tx['txn_id'] && isset($ipn['id_sale'])) {
            $api_admin->invoice_transaction_update(array('id'=>$id, 'txn_id'=>$ipn['id_sale']));
        }
    
        if(!$tx['txn_status'] && isset($ipn['status'])) {
            $api_admin->invoice_transaction_update(array('id'=>$id, 'txn_status'=>$ipn['status']));
        }
    
        if(!$tx['amount'] && isset($ipn['amount'])) {
            $api_admin->invoice_transaction_update(array('id'=>$id, 'amount'=>$ipn['amount']));
        }
    
        if(!$tx['currency'] && isset($ipn['currency'])) {
            $api_admin->invoice_transaction_update(array('id'=>$id, 'currency'=>$ipn['currency']));
        }

        $invoice = $api_admin->invoice_get(array('id'=>$data['get']['bb_invoice_id']));
        $client_id = $invoice['client']['id'];
        if($ipn['status'] == 'PERFORMED') {
            $bd = array(
                'id'            =>  $client_id,
                'amount'        =>  $ipn['amount'],
                'description'   =>  'Paylane transaction '.$ipn['id_sale'],
                'type'          =>  'Paylane',
                'rel_id'        =>  $ipn['id_sale'],
            );
            
            $api_admin->client_balance_add_funds($bd);
            if($tx['invoice_id']) {
                $api_admin->invoice_pay_with_credits(array('id'=>$tx['invoice_id']));
            }
            $api_admin->invoice_batch_pay_with_credits(array('client_id'=>$client_id));
        }
    
        $d = array(
            'id'        => $id,
            'error'     => '',
            'error_code'=> '',
            'status'    => 'processed',
            'updated_at'=> date('Y-m-d H:i:s'),
        );
        $api_admin->invoice_transaction_update($d);
    
        header("Location: ". $this->config['return_url']);
        exit;
    }

    public function isIpnDuplicate(array $ipn)
    {
        $sql = 'SELECT id
                FROM transaction
                WHERE txn_id = :transaction_id
                  AND txn_status = :transaction_status
                  AND amount = :transaction_amount
                LIMIT 2';

        $bindings = array(
            ':transaction_id' => $ipn['ik_trn_id'],
            ':transaction_status' => $ipn['ik_inv_st'],
            ':transaction_amount' => $ipn['ik_am'],
        );

        $rows = $this->di['db']->getAll($sql, $bindings);
        if (count($rows) > 1){
            return true;
        }


        return false;
    }

    public function getInvoiceItemDescription(array $invoice)
    {
        $desc = '';
        if (sizeof($invoice['lines']) > 0) {
            $desc = $invoice['lines'][0]['description'];
            for ($i=1; $i < sizeof($invoice['lines']); $i++) {
                $desc .= ", " . $invoice['lines'][$i]['description'];
            }
        }
        return substr($desc, 0, 10000);
    }

    /**
     * @see https://devzone.paylane.com/secure-form-guide/implementation/
     */
    public function getOneTimePaymentFields(array $invoice)
    {
        $data = array();
        $data['amount']                     = $this->moneyFormat($invoice['total'], $invoice['currency']); // Regular subscription price.
        $data['currency']                   = $invoice['currency'];
        $data['merchant_id']                = $this->config["merchant_id"];
        $data['description']                = substr($invoice['title'], 0, 20);
        $data['transaction_description']    = $this->getInvoiceItemDescription($invoice);
        $data['transaction_type']           = "S";
        $data['back_url']                   = $this->config['notify_url'];
        $data['language']                   = "en";
        $data['hash']                       = $this->setHash($data);
    }

    public function getSubscriptionFields(array $invoice)
    {
        throw new Payment_Exception('Not implemented yet');	
    }

    /**
     * @param string $url
     */
    private function _generateForm($url, $data, $method = 'post')
    {
        $form  = '';
        $form .= '<form name="payment_form" action="'.$url.'" method="'.$method.'">' . PHP_EOL;

        foreach($data as $key => $value) {
            $form .= sprintf('<input type="hidden" name="%s" value="%s" />', $key, $value) . PHP_EOL;
        }

        $form .=  '<input class="bb-button bb-button-submit" type="submit" value="Pay with PayLane" id="payment_button"/>'. PHP_EOL;
        $form .=  '</form>' . PHP_EOL . PHP_EOL;
        
        if(isset($this->config['auto_redirect']) && $this->config['auto_redirect']) {
            $form .= sprintf('<h2>%s</h2>', __('Redirecting to PayLane.com'));
            $form .= "<script type='text/javascript'>$(document).ready(function(){    document.getElementById('payment_button').style.display = 'none';    document.forms['payment_form'].submit();});</script>";
        }

        return $form;
    }

    private function setHash($data)
    {
        $array = array(
            $this->config["salt"],
            $data['description'],
            $data['amount'],
            $data['currency'],
            "S"
        );
        $string = implode("|", $array);
        return SHA1($string);
    }

    private function moneyFormat($amount, $currency)
    {
        //HUF currency do not accept decimal values
        if($currency == 'HUF') {
            return number_format($amount, 0);
        }
        return number_format($amount, 2, '.', '');
    }

    private function serviceUrl()
    {
        return 'https://secure.paylane.com/order/cart.html';
    }
}