var openFolder = "";  // id of the currently open folder (or empty string for none)

function base_id(id)
{
	return id.substr(0, id.length-1);
}

function show_hide_children(id, show)
{
	var div = document.getElementById(base_id(id)+"C");
	div.style.display = show ? "block" : "none";

}

// folder click
function fc(folder)
{
	show_hide_children(folder.id, true);
	
	// to do: update the knot too
	
	if (openFolder != folder.id)
	{
		var img, text, textId;
		
		img = document.getElementById(folder.id);
		img.src = "images/kb/folder_open.gif";
		
		if (openFolder != "")
		{
			img = document.getElementById(openFolder);
			img.src = "images/kb/folder_closed.gif"
		}
		
		show_docs(folder.id);
		go_to_browse_mode();
	}
	
	if (openFolder != "")
	{
		textId = base_id(openFolder) + "T";
		text = document.getElementById(textId);
		text.style.color = "black";
		text.style.backgroundColor = "white";
	}

	openFolder = folder.id;
	
	textId = base_id(folder.id) + "T";
	text = document.getElementById(textId);
	text.style.color = "white";
	text.style.backgroundColor = "black";
}

// knot click
function kc(knot)
{
	var img = document.getElementById(knot.id);
	var knotOpen = (img.src.substr(img.src.length-13,13) == "knot_open.gif");
	
	show_hide_children(knot.id, !knotOpen);
	img.src = knotOpen ? "images/kb/knot_closed.gif" : "images/kb/knot_open.gif";
	go_to_browse_mode();
}

function show_docs(id)
{
	var docDiv = document.getElementById(base_id(id)+"D");
	if (openFolder != "")
	{
		oldDiv = document.getElementById(base_id(openFolder)+"D");
		oldDiv.style.display = "none";
	}
	docDiv.style.display = "block";
}

function go_to_browse_mode()
{
	var p = document.getElementById("prevbutt");
	if (p != null) p.disabled = false;
	
	var r = document.getElementById("resultsDiv");
	if (r != null) r.style.display = "none";
}


function display_folder(folderName)
{
	var spans = document.getElementsByTagName("SPAN");
	
	for(var i=0;i<spans.length;i++)
	{
		if(spans[i].innerHTML == folderName)
		{
			fc(spans[i].parentNode);
			return true;
		}
	}
}