eatvio-infra/app/Http/Controllers/ChatController.php

<?php

namespace App\Http\Controllers;

use App\Events\ChatMessageUpdated;
use App\Models\Chat;
use App\Models\User;
use Illuminate\View\View;

class ChatMessage
{
    public $id;

    public $payload;

    public function __construct($id, $payload)
    {
        $this->id = $id;
        $this->payload = $payload;
    }

    public function someRandomFillFunction()
    {
        $users1 = User::all()->pluck('id');
        $users2 = User::all()->pluck('id');
        $faker = Faker\Factory::create();

        $users1->each(
            function ($user1, $key) use ($faker, $users2) {
                $users2->each(
                    function ($user2) use ($faker, $user1) {
                        if ($user1 === $user2) {
                            return;
                        }
                        $data1 = [
                            'from_user_id' => $user2,
                            'to_user_id' => $user1,
                            'data' => $faker->text(),
                        ];

                        $data2 = [
                            'from_user_id' => $user1,
                            'to_user_id' => $user2,
                            'data' => $faker->text(),
                        ];

                        $newMessage = (new Chat())->forceFill($data1);
                        $newMessage->save();
                        $newMessage = (new Chat())->forceFill($data2);
                        $newMessage->save();
                    }
                );
            }
        );
    }
}

class ChatController extends Controller
{
    public function index(): View
    {
        // $_ = "from_user_id to_user_id";
        $curUserId = Auth()->user()->id;
        $lastChatUsers = Chat::select(['from_user_id', 'to_user_id'])
            ->where('from_user_id', $curUserId)
            ->orWhere('to_user_id', $curUserId)
            ->get()
            ->map(fn ($e) => [$e['from_user_id'], $e['to_user_id']])
            ->flatten()
            ->unique()
            ->filter(fn ($e) => $e !== $curUserId)
            ->values()
            ->map(fn ($id) => User::find($id));

        $lastChatMessage = Chat::withLastUserMessage($curUserId);

        $lastChatRecipientUserId = $lastChatMessage->count() ? $lastChatMessage['from_user_id'] : null;

        if (! is_null($lastChatRecipientUserId) && $lastChatMessage['from_user_id'] === $curUserId) {
            $lastChatRecipientUserId = $lastChatMessage['to_user_id'];
        }

        return view(
            'chat.index',
            [
                'lastChatRecipientUserId' => $lastChatRecipientUserId,
                'lastChatUsers' => $lastChatUsers,
                'curUserId' => $curUserId,
                'chanId' => $this->makeChanName($curUserId, $lastChatRecipientUserId),
            ]
        );
    }

    /**
     * Show the form for creating a new resource.
     *
     * @return \Illuminate\Http\Response
     */
    public function create()
    {
        ChatMessageUpdated::dispatch(new ChatMessage(time(), 'some text '.md5(time())));
    }

    public function show(int $lastChatUser): View
    {
        $lastChatUser = User::find($lastChatUser);
        // $_ = "from_user_id to_user_id";
        $curUserId = Auth()->user()->id;

        $lastChatUsers = Chat::select(['from_user_id', 'to_user_id'])
            ->where('from_user_id', $curUserId)
            ->orWhere('to_user_id', $curUserId)
            ->get()
            ->map(fn ($e) => [$e['from_user_id'], $e['to_user_id']])
            ->flatten()
            ->unique()
            ->filter(fn ($e) => $e !== $curUserId)
            ->values()
            ->map(fn ($id) => User::find($id));

        return view(
            'chat.index',
            [
                'lastChatRecipientUserId' => $lastChatUser->id,
                'lastChatUsers' => $lastChatUsers,
                'curUserId' => $curUserId,
                'chanId' => $this->makeChanName($curUserId, $lastChatUser->id),
            ]
        );
    }

    private function makeChanName($from, $to)
    {
        return (int) $from < (int) $to
            ? $from.'_'.$to
            : $to.'_'.$from;
    }
}