shipping-portal/app/Http/Resources/ScheduleResource.php

<?php

namespace App\Http\Resources;

use Illuminate\Http\Resources\Json\JsonResource;
use Carbon\Carbon;

class ScheduleResource extends JsonResource
{
    /**
     * Transform the resource into an array.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return array
     */
    public function toArray($request)
    {
        return [
            'id' => $this->id,
            'etd' => $this->etd ? $this->etd->format('d-m-Y') : 'n/a',
            'eta' => $this->eta ? $this->eta->format('d-m-Y') : 'n/a',
            'billing_days_left' => [
                'value' => (Carbon::parse($this->eta)->subDays(7)->gt(Carbon::now())) ? '+' : '-' ,
                'duration' => Carbon::parse($this->eta)->subDays(7)->diffInDays(Carbon::now()),
            ],
            'status' => $this->status,
        ];
    }
}