core/app/Handlers/Registrators/SearchEngineRegistrator.php

<?php
namespace App\Handlers\Registrators;

use App\Enumerations\Exceptions\EnumerationExistsException;
use App\Handlers\Contracts\SearchHandler;
use App\Handlers\Contracts\SearchPresenterHandler;
use App\Handlers\Registrators\Items\SearchEngine;
use Symfony\Component\Process\Exception\InvalidArgumentException;

class SearchEngineRegistrator
{
    const ADMIN = 'admin';
    const VISITOR = 'visitor';
    protected $searchEngines;

    function __construct($app)
    {
        $this->searchEngines = [
            self::ADMIN   => [],
            self::VISITOR => []
        ];
    }

    /**
     * Method for registering new settings extensions/parts
     *
     * @param SearchHandler          $search
     * @param SearchPresenterHandler $presenter
     *
     * @param                        $type
     *
     * @throws EnumerationExistsException
     */
    public function register(SearchHandler $search, SearchPresenterHandler $presenter, $type)
    {
        $this->checkIfRegistered($type, $search->getId());

        // register new extension
        $this->searchEngines[$type][$search->getId()] = [$search, $presenter];
    }

    /**
     * Getter for all registered extensions
     *
     * @param $type
     *
     * @return array
     */
    public function get($type)
    {
        if (!isset($this->searchEngines[$type])) {
            throw new InvalidArgumentException('Invalid type ' . $type);
        }

        return $this->searchEngines[$type];
    }

    /**
     * Checks if this section is not already defined
     *
     * @param $type
     * @param $id
     *
     * @throws EnumerationExistsException
     */
    private function checkIfRegistered($type, $id)
    {
        if (isset($this->searchEngines[$type][$id])) {
            throw new EnumerationExistsException('Already existing search engine ' . $id . ' in ' . $type);
        }
    }
}