Understanding Adapter Design Pattern

AdapterPattern.php

<?php

interface BankAccounts{
  
    public function createBankAccount();
}


interface PaymentGateways extends BankAccounts
{

    public function processpayment(float|int $amount);

    public function createAccount(string $name);

}

class Paystack implements PaymentGateways
{

    public $name = 'Paystack';

    public function __construct()
    {
    }

    function createBankAccount()
    {
        // TODO: Implement createBankAccount() method.
    }

    public function processpayment(float|int $amount)
    {
        // TODO: Implement processpayment() method.
    }

    public function createAccount(string $name)
    {
        return "{$name} has been created";
    }

}


class PaymentAdapter
{
    private $paymentGateway;


    public function __construct(PaymentGateways $paymentGateway)
    {
        $this->paymentGateway = $paymentGateway;
    }

    public function processPayment($amount) {
        $response = $this->paymentGateway->processPayment($amount);
        return array('status' => $response['status'], 'transaction_id' => $response['transaction_id'], 'payment_method' => get_class($this->paymentGateway));
    }

    public function createAccount(string $accountName){
        return $this->paymentGateway->createAccount($accountName);

    }
    
}

class TestController extends Controller{

    private $paymentAdapter;

    public function __construct(PaymentAdapter $paymentAdapter) {
        $this->paymentAdapter = $paymentAdapter;
    }

    public function createAccount($name) {
        $this->paymentAdapter = new PaymentAdapter(new Paystack());
        echo $this->paymentAdapter->createAccount($name);
    }
}