Mrthdrb

There is an event that checks if the goods in the basket when we go to the product page. If there is an attribute in the goods that allows to deliver the goods on the day of the order, if this attribute is included in the product, then it returns "1" if it is disabled, then there is nothing.
Now how to show the popup when you click on "add to cart" on the product page if there is already a product in the basket with the possibility of delivery today, and the second product that we want to add does not have this possibility.
And on the pop-up there should be two buttons, "Continue" or "Cancel". If the user clicks "Continue" then we add the item to the basket, and if the user clicks "Cancel", then we close the popup and there is nothing to add to the basket.

Observer->DayDelivery.php

namespace RonisSameDayDeliveryObserver;

use MagentoFrameworkEventObserverInterface;
use MagentoCatalogModelResourceModelProductCollectionFactory;

class DayDelivery implements ObserverInterface

 protected $resultPageFactory;

 /**
 * @var MagentoCheckoutModelCart
 */
 protected $_cart;
 protected $_productCollectionFactory;
 protected $_resultJsonFactory;

 /**
 * [__construct description]
 * @param MagentoFrameworkAppActionContext $context [description]
 * @param MagentoFrameworkViewResultPageFactory $resultPageFactory [description]
 * @param MagentoCheckoutModelCart $cart [description]
 */
 public function __construct(
 MagentoFrameworkControllerResultJsonFactory $resultJsonFactory,
 MagentoFrameworkAppActionContext $context,
 MagentoFrameworkViewResultPageFactory $resultPageFactory,
 MagentoCheckoutModelCart $cart,
 CollectionFactory $productCollectionFactory
 )
 
 $this->resultPageFactory = $resultPageFactory;
 $this->_cart = $cart;
 $this->_resultJsonFactory = $resultJsonFactory;
 $this->_productCollectionFactory = $productCollectionFactory;
 

 public function execute(MagentoFrameworkEventObserver $observer)
 
 $writer = new ZendLogWriterStream(BP . '/var/log/samDayDelivery.log');
 $logger = new ZendLogLogger();
 $logger->addWriter($writer);

 $cartProductIds = $this->_cart->getQuoteProductIds();
 $productCollection = $this->_productCollectionFactory->create();
 if (!$cartProductIds) 
 return false;
 else 
 $productCollection->addFieldToFilter('entity_id', ['in' => [$cartProductIds]]);
 $productCollection->addAttributeToSelect('allow_same_day_delivery');
 foreach ($productCollection as $item) 
 $id = $item->getId();
 $check = $item->getData('allow_same_day_delivery');
 $logger->info('Delivery sam day id: ' . $id . ' status ' . $check);
 
// $result = $this->_resultJsonFactory->create()->setData(['Shipment check' => $check]);
// return $result;