function showCategoryTree($module) {
$category_tree = '';
$category_tree .= '<div class="clearfix"></div><div id="menutree" class="row">';
$root_level='';
$second_level='';
$third_level='';
$stmt = DBi::$conn->query('SELECT * from kategorie WHERE id_cat_parent= 0 ORDER BY id_cat DESC');
foreach($stmt as $row) {
$root_level++;
$category_tree .='<div class="col-md-12 col-sm-12 col-xs-12">';
$category_tree .= '<div class="cat_head menu_label">';
$category_tree .= $row['nazwa'];
$category_tree .= '</div>';
$category_tree .= '<div class="cat_head_2 menu_label">';
$category_tree .= '<a href="index.php?modul='.$module.'&kasuj=TRUE&id='.$row['id_cat'].'&action_get=remove_category">';
$category_tree .= '<i class="fa fa-remove"></i> KASUJ</a>';
$category_tree .= '</div>';
$category_tree .= '<a data-toggle="collapse" data-target="#tree-menu-'.$root_level.'">';
$category_tree .= '<i class="fa-3x fa fa-toggle-down"></i></a>';
$category_tree .= '</div>';
$category_tree .= '<div id="tree-menu-'.$root_level.'" class="col-md-12 col-sm-12 col-xs-12 collapse">';
$stmtB = DBi::$conn->query('SELECT * from kategorie WHERE id_cat_parent= '.$row['id_cat'].' ORDER BY id_cat DESC');
foreach($stmtB as $rowB) {
$second_level++;
$category_tree .= '<div class="tree-level-2 col-md-12 col-sm-12 col-xs-12">';
$category_tree .= '<div class="col-md-3 col-sm-3 col-xs-3">';
$category_tree .= '<i class="fa-2x fa fa-rotate-90 fa-level-up" aria-hidden="true"></i> ';
$category_tree .= '<div class="cat_head menu_label">'.$rowB['nazwa'];
if (IlePodkategorii($rowB['id_cat']) > '0') {
$category_tree .=' <i class="fa fa-level-down" aria-hidden="true"></i>';
}
$category_tree .= '</div>';
$category_tree .= '</div>';
$category_tree .= '<div class="col-md-2 col-sm-2 col-xs-2">';
if (IlePodkategorii($rowB['id_cat']) > '0') {
$category_tree .= '<a data-toggle="collapse" data-target="#tree-menu-second'.$second_level.'">';
$category_tree .= '<i class="fa-3x fa fa-toggle-down"></i>';
$category_tree .= '</a>';
}
$category_tree .= '</div>';
$category_tree .= '<div class="col-md-7 col-sm-7 col-xs-7">';
$category_tree .= '<div class="cat_head_2 menu_label">';
$category_tree .= '<a href="index.php?modul='.$module.'&kasuj=TRUE&id='.$rowB['id_cat'].'&action_get=remove_category">';
$category_tree .= '<i class="fa fa-remove"></i> KASUJ</a>';
$category_tree .= '</div>';
$category_tree .= '<div class="cat_head_2 menu_label">';
$category_tree .= '<a href="index.php?modul='.$module.'&edytuj=TRUE&id='.$rowB['id_cat'].'">';
$category_tree .= '<i class="fa fa-pencil"></i> EDYTUJ</a>';
$category_tree .= '</div>';
$category_tree .= '</div>';
$category_tree .= '</div>';
$category_tree .= '<div id="tree-menu-second'.$second_level.'" class="col-md-12 col-sm-12 col-xs-12 collapse">';
$stmtC = DBi::$conn->query('SELECT * from kategorie WHERE id_cat_parent= '.$rowB['id_cat'].' ORDER BY id_cat DESC');
foreach($stmtC as $rowC) {
$third_level++;
$category_tree .= '<div class="tree-level-3 col-md-12 col-sm-12 col-xs-12">';
$category_tree .= '<div class="col-md-4 col-sm-4 col-xs-4">';
$category_tree .= '<i class="fa-2x fa fa-rotate-90 fa-level-up" aria-hidden="true"></i> ';
$category_tree .= '<div class="cat_head menu_label">'.$rowC['nazwa'];
$category_tree .= '</div>';
$category_tree .= '</div>';
$category_tree .= '<div class="col-md-2 col-sm-2 col-xs-2">';
$category_tree .= '</div>';
$category_tree .= '<div class="col-md-7 col-sm-7 col-xs-7">';
$category_tree .= '<div class="cat_head_2 menu_label">';
$category_tree .= '<a href="index.php?modul='.$module.'&kasuj=TRUE&id='.$rowC['id_cat'].'&action=remove_category">';
$category_tree .= '<i class="fa fa-remove"></i> KASUJ</a>';
$category_tree .= '</div>';
$category_tree .= '<div class="cat_head_2 menu_label">';
$category_tree .= '<a href="index.php?modul='.$module.'&edytuj=TRUE&id='.$rowC['id_cat'].'">';
$category_tree .= '<i class="fa fa-pencil"></i> EDYTUJ</a>';
$category_tree .= '</div>';
$category_tree .= '</div>';
$category_tree .= '</div>';
}
$category_tree .= '</div>';
}
$category_tree .= '</div>';
}
$category_tree .= '</div><div class="clearfix"></div>';
}