/*
 * Content-seperated javascript tree widget
 * Copyright (C) 2005 SilverStripe Limited
 * Feel free to use this on your websites, but please leave this message in the fies
 * http://www.silverstripe.com/blog
*/

/*
 * Initialise all trees identified by <ul class="tree">
 */
/*
 * Initialise a tree node, converting all its LIs appropriately
 */
function initTree(el) {
	var i,j;
	var spanA, spanB, spanC;
	var startingPoint, stoppingPoint, childUL;
	

	// Find all LIs to process
	for(i=0;i<el.childNodes.length;i++) {
		if(el.childNodes[i].tagName && el.childNodes[i].tagName.toLowerCase() == 'li') {
			var li = el.childNodes[i];

			// Create our extra spans
			spanA = document.createElement('span');
			spanB = document.createElement('span');
			//spanC = document.createElement('span');
			spanA.appendChild(spanB);
			//spanB.appendChild(spanC);
			spanA.className = 'a ' + li.className.replace('closed','spanClosed');
			spanA.onMouseOver = function() {}
			spanB.className = 'b';
			spanB.onclick = treeToggle;
			//spanC.className = 'c';
			
			
			// Find the UL within the LI, if it exists
			stoppingPoint = li.childNodes.length;
			startingPoint = 0;
			childUL = null;
			for(j=0;j<li.childNodes.length;j++) {
				if(li.childNodes[j].tagName && li.childNodes[j].tagName.toLowerCase() == 'div') {
					startingPoint = j + 1;
					continue;
				}

				if(li.childNodes[j].tagName && li.childNodes[j].tagName.toLowerCase() == 'ul') {
					childUL = li.childNodes[j];
					stoppingPoint = j;
					break;					
				}
			}
				
			// Move all the nodes up until that point into spanC
			for(j=startingPoint;j<stoppingPoint;j++) {
				spanB.appendChild(li.childNodes[startingPoint]);
			}
			
			// Insert the outermost extra span into the tree
			if(li.childNodes.length > startingPoint) li.insertBefore(spanA, li.childNodes[startingPoint]);
			else li.appendChild(spanA);
			
			// Process the children
			if(childUL != null) {
				if(initTree(childUL)) {
					$(li).addClassName('children', 'closed');
					$(spanA).addClassName('children', 'spanClosed');
				}
			}
		}
	}
	
	if(li) {
		// li and spanA will still be set to the last item

		$(li).addClassName('last', 'closed');
		$(spanA).addClassName('last', 'spanClosed');
		return true;
	} else {
		return false;
	}
		
}
 

/*
 * +/- toggle the tree, where el is the <span class="b"> node
 * force, will force it to "open" or "close"
 */
function treeToggle(el, force) {
	el = this;
	
	while(el != null && (!el.tagName || el.tagName.toLowerCase() != "li")) el = el.parentNode;
	
	// Get UL within the LI
	var childSet = findChildWithTag(el, 'ul');
	var topSpan = findChildWithTag(el, 'span');

  //First get the contents of this treenode if that's not already done
	if(! $(childSet).hasClassName('clicked')) {	
    new Ajax.Updater(childSet.id, '/sampler/update_tree/' + childSet.id, 
                    {asynchronous:true, evalScripts:true, onComplete:function(request){initTree($(childSet.id));}});
	 $(childSet).addClassName('clicked');
  }

	if( force != null ){
		
		if( force == "open"){
			treeOpen( topSpan, el )
		}
		else if( force == "close" ){
			treeClose( topSpan, el )
		}
		
	}
	
	else if( childSet != null) {
		// Is open, close it
		if(!el.className.match(/(^| )closed($| )/)) {		
			treeClose( topSpan, el );
		// Is closed, open it
		} else {
			treeOpen( topSpan, el );
		}
	}
}


function treeOpen( a, b ){
  $(a).removeClassName('spanClosed');
  $(b).removeClassName('closed');
}
	
	
function treeClose( a, b ){
  $(a).addClassName('spanClosed');
  $(b).addClassName('closed');
}

/*
 * Find the a child of el of type tag
 */
function findChildWithTag(el, tag) {
	for(var i=0;i<el.childNodes.length;i++) {
		if(el.childNodes[i].tagName != null && el.childNodes[i].tagName.toLowerCase() == tag) return el.childNodes[i];
	}
	return null;
}