alevel_project/app/Models/Offer.php

<?php

namespace App\Models;

use App\Models\Item as Item;
use App\User;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\SoftDeletes;

class Offer extends Model
{
    use SoftDeletes;

    protected $dates = ['deleted_at'];
    protected $table = "offers";
    protected $guarded = ['id'];
    protected $fillable = ["item_id", "item_offer_id", 'status_id'];

    public function itemId()
    {
        return $this->hasOne('item', 'id', 'item_id');
    }

    public function itemOfferId()
    {
        return $this->hasOne('item', 'id', 'item_offer_id');
    }

    public function users()
    {
        return $this->hasManyThrough('App\Item', 'App\User');
    }

    public function items()
    {
        return $this->belongsTo(Item::class, 'id')->orWhere('items.id', $this->item_offer_id);
    }

    public function status()
    {
        return $this->$this->belongsTo('statuses', 'id', 'status_id');
    }

    public function getItems()
    {
        $this->attributes['items'] =[];
//        $items = $this->belongsTo(Item::class, 'id')->orWhere('items.id', $this->item_offer_id)->get();
//        foreach ($items as $item) {
//            if ($this->attributes['item_offer_id'] === $item->id) {
                $this->attributes['items'][0] = Item::find($this->attributes['item_id']);
//            } else {
                $this->attributes['items'][1] = Item::find($this->attributes['item_offer_id']);
//            }
//        }
        return $this->attributes['items'];
//        return $this->attributes['items'] = Item::find([$this->attributes['item_id'], $this->attributes['item_offer_id']]);
    }

    public function getUsers()
    {
        $this->attributes['users']['seller'] = User::where('items.id', $this->attributes['item_offer_id'])
            ->join('items', 'items.user_id', 'users.id')->first();
        $this->attributes['users']['buyer'] = User::where('items.id', $this->attributes['item_offer_id'])
            ->join('items', 'items.user_id', 'users.id')->first();
        return $this->attributes['users'];
    }

    public function buyer()
    {
        return $this->hasManyThrough('App\User', 'App\Models\Item', 'user_id', 'item_offer_id');
    }

    public function seller()
    {
        return $this->hasManyThrough('App\User', 'App\Models\Item', 'user_id', 'item_id');
    }

    public function __get($key)
    {
        if ($key === "items") {
            return $this->attributes['items'] ?? $this->getItems();
        }
        if ($key === "users") {
            return $this->attributes['users'] ?? $this->getUsers();
        }

        return parent::__get($key);
    }
}