ldc-mesbr-app/app/Models/Campaign.php

<?php

namespace App\Models;

use App\Enums\CampaignTypes;
use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Database\Eloquent\Relations\BelongsToMany;

class Campaign extends Model
{
    use HasFactory;

    /**
     * The attributes that should be cast.
     *
     * @var array
     */
    protected $casts = [
        'type' => CampaignTypes::class,
    ];

    // * RELATIONS

    /**
     * Get the brand that owns the Campaign
     *
     * @return \Illuminate\Database\Eloquent\Relations\BelongsTo
     */
    public function brand(): BelongsTo
    {
        return $this->belongsTo(Brand::class);
    }

    /**
     * Get coupons that owned by the Campaign
     *
     * @return \Illuminate\Database\Eloquent\Relations\BelongsToMany
     */
    public function coupons(): BelongsToMany
    {
        return $this->belongsToMany(Coupon::class);
    }
}