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

<?php

namespace App\Http\Controllers;

use App\Models\Diary;
use Carbon\Carbon;
use Carbon\CarbonPeriod;
use Illuminate\Contracts\View\Factory as ViewFactory;
use Illuminate\Contracts\View\View;
use Illuminate\Support\Facades\Auth;
use Mcamara\LaravelLocalization\Facades\LaravelLocalization;

class CalendarController extends Controller
{
    public int $weekStartsAt;

    public int $weekEndsAt;

    public Carbon $startsAt;

    public Carbon $endsAt;

    public Carbon $gridStartsAt;

    public Carbon $gridEndsAt;

    public function __construct(?int $initialYear = null, ?int $initialMonth = null, ?int $weekStartsAt = null)
    {
        $this->weekStartsAt = $weekStartsAt ?? Carbon::MONDAY;
        $this->weekEndsAt = $this->weekStartsAt === Carbon::MONDAY
            ? Carbon::SUNDAY
            : collect([0, 1, 2, 3, 4, 5, 6])->get($this->weekStartsAt + 6 - 7);

        $initialYear = $initialYear ?? Carbon::today()->year;
        $initialMonth = $initialMonth ?? Carbon::today()->month;

        $this->startsAt = Carbon::createFromDate($initialYear, $initialMonth, 1)->startOfDay();
        $this->endsAt = $this->startsAt->clone()->endOfMonth()->startOfDay();
        $this->calculateGridStartsEnds();
    }

    public function calculateGridStartsEnds(): void
    {
        $this->gridStartsAt = $this->startsAt->clone()->startOfWeek($this->weekStartsAt);
        $this->gridEndsAt = $this->endsAt->clone()->endOfWeek($this->weekEndsAt);
    }

    public function index(): View|ViewFactory
    {
        $curUser = Auth::user();
        $fullGridPeriod = CarbonPeriod::create(
            $this->gridStartsAt,
            '1 day',
            $this->gridEndsAt
        );

        $filledDays = Diary::where('user_id', $curUser->id)
            ->whereMonth('date', (string) now()->month)
            ->get()
            ->keyBy('date');

        return view(
            'calendar.index',
            [
                'fullGridPeriod' => $fullGridPeriod,
                'currentLocale' => LaravelLocalization::getCurrentLocale(),
                'filledDays' => $filledDays,
                'curUser' => $curUser,
            ]
        );
    }
}