AUI.add('aui-tool-set', function(A) {
var Lang = A.Lang,
	isArray = Lang.isArray,
	isNumber = Lang.isNumber,
	isString = Lang.isString,

	isToolItem = function(item) {
		return (item instanceof A.ToolItem);
	},

	getClassName = A.ClassNameManager.getClassName,

	NAME = 'toolset',

	CSS_FIRST = getClassName(NAME, 'first'),
	CSS_ITEM = getClassName(NAME, 'item'),
	CSS_ITEM_CONTENT = getClassName(NAME, 'item', 'content'),
	CSS_LAST = getClassName(NAME, 'last'),
	CSS_TOOLSET = getClassName(NAME),

	TPL_GENERIC = '<span></span>';

var ToolSet = function() {
	ToolSet.superclass.constructor.apply(this, arguments);
};

ToolSet.NAME = NAME;

ToolSet.ATTRS = {
	activeState: {},
	defaultState: {},
	hoverState: {},

	tools: {
		value: [],
		validator: isArray
	}
};

A.extend(
	ToolSet,
	A.Component,
	{
		BOUNDING_TEMPLATE: TPL_GENERIC,
		CONTENT_TEMPLATE: TPL_GENERIC,

		/*
		* Lifecycle
		*/
		initializer: function() {
			var instance = this;

			instance.tools = new A.DataSet();

			instance.tools.on('add', instance._afterAddToolItem, instance);
			instance.tools.on('remove', instance._afterRemoveToolItem, instance);
		},

		renderUI: function() {
			var instance = this;
			var toolItems = instance.get('tools');

			A.each(toolItems, function(item, i) {
				instance.add(item);
			});
		},

		syncUI: function() {
			var instance = this;
			var toolItems = instance.get('tools');
			var toolSet = instance.tools;
			var length = toolSet.size() - 1;

			// loop all items applying the CSS_FIRST and
			// CSS_LAST class names on the correct elements
			toolSet.each(function(item, index) {
				var itemBoundingBox = item.get('boundingBox');

				itemBoundingBox.removeClass(CSS_FIRST);
				itemBoundingBox.removeClass(CSS_LAST);

				if (index == 0) {
					itemBoundingBox.addClass(CSS_FIRST);
				}

				if (index == length) {
					itemBoundingBox.addClass(CSS_LAST);
				}
			});
		},

		/*
		* Methods
		*/
		add: function(toolItem) {
			var instance = this;
			var toolSet = instance.tools;

			// fix the toolItem argument the user passed, supports plain object, ToolItem and String
			// NOTE: if ToolItem passed as argument it will return the same instance
			toolItem = instance._createToolItem(toolItem);

			if (!toolSet.contains(toolItem)) {
				toolSet.add(toolItem);
			}
		},

		item: function(key) {
			var instance = this;

			return instance.tools.item(key);
		},

		remove: function(item) {
			var instance = this;
			var toolSet = instance.tools;

			if (isNumber(item)) {
				toolSet.removeAt(item);
			}
			if (isString(item)) {
				toolSet.removeKey(item);
			}
			else {
				toolSet.remove(item);
			}
		},

		_createToolItem: function(item) {
			var instance = this;
			var toolItem = null;

			// check if is needed to instantiate a new ToolItem
			if (isToolItem(item)) {
				toolItem = item;
			}
			else {
				var defaultToolConfig = {
					activeState: instance.get('activeState'),
					defaultState: instance.get('defaultState'),
					hoverState: instance.get('hoverState')
				};

				if (isString(item)) {
					item = {
						icon: item
					};
				}

				A.mix(item, defaultToolConfig);

				toolItem = new A.ToolItem(item);
			}

			var itemBoundingBox = toolItem.get('boundingBox');
			var itemContentBox = toolItem.get('contentBox');

			itemBoundingBox.addClass(CSS_ITEM);
			itemContentBox.addClass(CSS_ITEM_CONTENT);

			return toolItem;
		},

		/*
		* Listeners
		*/
		_afterAddToolItem: function(event) {
			var instance = this;
			var toolItem = event.item;
			var contentBox = instance.get('contentBox');

			if (isToolItem(toolItem)) {
				toolItem.render(contentBox);
			}

			instance.syncUI();
		},

		_afterRemoveToolItem: function(event) {
			var instance = this;
			var toolItem = event.item;
			var contentBox = instance.get('contentBox');

			if (isToolItem(toolItem)) {
				toolItem.destroy();
			}

			instance.syncUI();
		}
	}
);

A.ToolSet = ToolSet;

}, '0.1a' ,{requires:['aui-data-set','aui-tool-item'], skinnable:true});