exchange-2.0/app/Models/Transaction.php

<?php

namespace App\Models;

use App\Classes\General\Interfaces\Documentable;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Database\Eloquent\Relations\HasMany;
use Illuminate\Database\Eloquent\Relations\MorphMany;


class Transaction extends AbstractModel implements Documentable
{
    protected $table = 'transactions';

    /**
     * @return BelongsTo
     */
    public function booking(): BelongsTo
    {
        return $this->BelongsTo( booking::class, 'booking_id', 'id');
    }

    /**
     * @return MorphMany
     */
    public function documents(): morphMany
    {
        return $this->morphMany(Document::class, 'owner');
    }

    /**
     * @return BelongsTo
     */
    public function currency(): BelongsTo
    {
        return $this->BelongsTo(Currency::class, 'currency_id', 'id');
    }

    /**
     * @return BelongsTo
     */
    public function original_currency(): BelongsTo
    {
        return $this->BelongsTo(Currency::class, 'original_currency_id', 'id');
    }

    /**
     * @return HasMany
     */
    public function transactionDetails(): HasMany
    {
        return $this->HasMany(TransactionDetail::class, 'transaction_id', 'id');
    }

    public function convert_original_amount()
    {
        if($this->booking()->first()->fix_currency_id !== 1) {
            $currency_rate = $this->currency()->first()->rates()->where('payment_method_type', $this->payment_method)->first();
            return number_format($this->original_amount / $currency_rate->selling, 2);
        }
        return $this->original_amount;
    }
}