invoiceninja/app/Services/Invoice/AutoBillInvoice.php

<?php
/**
 * Invoice Ninja (https://invoiceninja.com)
 *
 * @link https://github.com/invoiceninja/invoiceninja source repository
 *
 * @copyright Copyright (c) 2020. Invoice Ninja LLC (https://invoiceninja.com)
 *
 * @license https://opensource.org/licenses/AAL
 */

namespace App\Services\Invoice;

use App\DataMapper\InvoiceItem;
use App\Events\Payment\PaymentWasCreated;
use App\Factory\PaymentFactory;
use App\Models\Client;
use App\Models\Invoice;
use App\Models\Payment;
use App\Services\AbstractService;
use App\Services\Client\ClientService;
use App\Services\Payment\PaymentService;
use App\Utils\Traits\GeneratesCounter;

class AutoBillInvoice extends AbstractService
{

    private $invoice;

    private $client; 

    public function __construct(Invoice $invoice)
    {
        $this->invoice = $invoice;
    
        $this->client = $invoice->client;
    }

    public function run()
    {

        if(!$this->invoice->isPayable())
            return $this->invoice;

        if($this->invoice->balance > 0)
            $gateway_token = $this->getGateway($this->invoice->balance);
        else
            return $this->invoice->service()->markPaid()->save();

        $fee = $gateway_token->gateway->calcGatewayFee($this->invoice->balance);

        if($fee > 0)
            $this->addFeeToInvoice($fee);

        $response = $gateway_token->gateway->driver($this->client)->tokenBilling($gateway_token, $amount);

        //if response was successful, toggle the fee type_id to paid
    }

    private function getGateway($amount)
    {

        $gateway_tokens = $this->client->gateway_tokens()->orderBy('is_default', 'DESC');

        return $gateway_tokens->filter(function ($token) use ($amount){

            return $this->validGatewayLimits($token, $amount);

        })->all()->first();

    }

    private function addFeeToInvoice(float $fee)
    {
        $item = new InvoiceItem;
        $item->quantity = 1;
        $item->cost = $fee;
        $item->notes = ctrans('texts.online_payment_surcharge');
        $item->type_id = 3;

        $items = (array)$this->invoice->line_items;
        $items[] = $item;

        $this->invoice->line_items = $items;
        $this->invoice->save();

        $this->invoice = $this->invoice->calc()->getInvoice()->save();

        return $this;
    }

    /**
     * Checks whether a given gateway token is able
     * to process the payment after passing through the
     * fees and limits check
     *     
     * @param  CompanyGateway $cg     The CompanyGateway instance
     * @param  float          $amount The amount to be paid
     * @return bool
     */
    public function validGatewayLimits($cg, $amount) : bool
    {
        if(isset($cg->fees_and_limits))
            $fees_and_limits = $cg->fees_and_limits->{"1"};
        else
            $passes = true;

        if ((property_exists($fees_and_limits, 'min_limit')) && $fees_and_limits->min_limit !==  null && $amount < $fees_and_limits->min_limit) {
            info("amount {$amount} less than ". $fees_and_limits->min_limit);
            $passes = false;   
        }
        else if ((property_exists($fees_and_limits, 'max_limit')) && $fees_and_limits->max_limit !==  null && $amount > $fees_and_limits->max_limit){ 
            info("amount {$amount} greater than ". $fees_and_limits->max_limit);
            $passes = false;
        }
        else
            $passes = true;

        return $passes;
    }

}