warehouse/app/Http/Controllers/Locations/ShowLocationsController.php

<?php

namespace App\Http\Controllers\Locations;

use App\Models\Location;
use App\Models\Stock;
use Framework\Routing\Router;

class ShowLocationsController
{
    public function handle(Router $router)
    {
        $locations = Location::all();
        $stock = Stock::all();

        $totalsByLocation = [];

        foreach ($stock as $row) {
            $totalsByLocation[$row->location_id] = ($totalsByLocation[$row->location_id] ?? 0) + $row->quantity;
        }

        foreach ($locations as $location) {
            $location->totalQuantity = $totalsByLocation[$location->id] ?? 0;
            $location->route = $router->route('view-location', ['location' => $location->id]);
        }

        return view('locations/index', [
            'locations' => $locations,
            'createAction' => $router->route('show-create-location-form'),
            'canManage' => session()->has('user_id'),
        ]);
    }
}