/**
 * Copyright (c) 2006-2015, JGraph Holdings Ltd
 * Copyright (c) 2006-2015, draw.io AG
 */
mxCodecRegistry.register(function()
{
	/**
	 * Class: mxRootChangeCodec
	 *
	 * Codec for <mxRootChange>s. This class is created and registered
	 * dynamically at load time and used implicitly via <mxCodec> and
	 * the <mxCodecRegistry>.
	 *
	 * Transient Fields:
	 *
	 * - model
	 * - previous
	 * - root
	 */
	var codec = new mxObjectCodec(new mxRootChange(),
		['model', 'previous', 'root']);

	/**
	 * Function: onEncode
	 *
	 * Encodes the child recursively.
	 */
	codec.afterEncode = function(enc, obj, node)
	{
		enc.encodeCell(obj.root, node);
		
		return node;
	};

	/**
	 * Function: beforeDecode
	 *
	 * Decodes the optional children as cells
	 * using the respective decoder.
	 */
	codec.beforeDecode = function(dec, node, obj)
	{
		if (node.firstChild != null &&
			node.firstChild.nodeType == mxConstants.NODETYPE_ELEMENT)
		{
			// Makes sure the original node isn't modified
			node = node.cloneNode(true);
			
			var tmp = node.firstChild;
			obj.root = dec.decodeCell(tmp, false);

			var tmp2 = tmp.nextSibling;
			tmp.parentNode.removeChild(tmp);
			tmp = tmp2;
		
			while (tmp != null)
			{
				tmp2 = tmp.nextSibling;
				dec.decodeCell(tmp);
				tmp.parentNode.removeChild(tmp);
				tmp = tmp2;
			}
		}
		
		return node;
	};
	
	/**
	 * Function: afterDecode
	 *
	 * Restores the state by assigning the previous value.
	 */
	codec.afterDecode = function(dec, node, obj)
	{
		obj.previous = obj.root;
		
		return obj;
	};

	// Returns the codec into the registry
	return codec;

}());
