//funkce nutne pro treemenu
//Použití: mod_catalogue,mod_eshop,mod_ck

//prekresluje obrazky plusu a minusu
function swap_image(id)
{
	image_menu=document.getElementById(id);
	var old_src=image_menu.src;
	var match_string_minus=/minus/;
	var match_string_plus=/plus/;
	if(old_src.search(match_string_minus)!=-1)
	{
		var temp=old_src;
		new_src=temp.replace(match_string_minus,"plus");
	}
	if(old_src.search(match_string_plus)!=-1)
	{
		var temp=old_src;
		new_src=temp.replace(match_string_plus,"minus");
	}	 
	image_menu.src=new_src;
}

//zobrazuje a skryva uzly menu
//type je typ menu (eshop,ck,catalogue, kvuli kolizi id vrstev a images)
//id je cislo prvku
//display_type je typ elementu bud block nebo inline
//sw_image je hodnota 1 pokud se ma volat swap image a 0 pokud ne
function switch_menu(display_type,type,id,sw_image)
{   
	var layer_id=type+"_tree_layer"+id;
	var tree_item_id=type+"_tree_item"+id;
	var kat_layer=document.getElementById(layer_id);
	
	if(kat_layer.style.display==display_type)
	{
		kat_layer.style.display="none";
		
		if(sw_image==1)
		{
			swap_image(tree_item_id);
		}
	}
	else
	{
		kat_layer.style.display=display_type;
		
		if(sw_image==1)
		{
			swap_image(tree_item_id);
		}
	}   
}