<?php 
$db = $GLOBALS['db'];
$r=$db->query("select * from ecmstockoperations where 
product_id='582' 
and stock_id='c7afd71a-4c3a-bde4-138d-4acaee1644e4' 
and in_id is null and used=0 and type=0");
$docs=array();
$l=0;
while($tmp=$db->fetchByAssoc($r)){
    
    $ii=$db->query("select * from ecmstockoperations where in_id='".$tmp['id']."' and type=1");
    if($ii->num_rows>0){
        $quantity_tmp=$tmp['quantity'];
        while($tmp2=$db->fetchByAssoc($ii)){
          
            $quantity_tmp-=$tmp2['quantity'];
        }
        $doc['quantity']=$quantity_tmp;
        $doc['parent_name']=$tmp['parent_name'];
        $docs[]=$doc;
    } else {
        $doc['quantity']=$tmp['quantity'];
        $doc['parent_name']=$tmp['parent_name'];
        $docs[]=$doc;
    }
}
var_dump($docs);
?>