<?php

namespace App\User;

/**
 * Class PreviousDataObjTrait
 * @package App\User
 * @mixin \Qs_Db_Obj
 */
trait PreviousDataObjTrait
{
    protected $_previousData = [];

    public function update(array $data = null)
    {
        $this->_initPreviousData();
        return parent::update($data);
    }

    protected function _initPreviousData()
    {
        if ($primaryKey = $this->getPrimaryKey()) {
            $this->_previousData = $this->_getFromDb($primaryKey);
        }
        return $this;
    }

    public function getPreviousData()
    {
        return $this->_previousData;
    }
}