/**
 * A utility function that sets the listeners for a tab which are then passed in the generated VDom.  The function
 * returns a handle that can be used to clean up the listeners
 * @param tabbed The tabbed mixin that should be effected when the listeners fire
 * @param tab The tab that the listeners are referring to
 */
function setTabListeners(tabbed: TabbedMixin<TabbedChild, TabbedState>, tab: TabbedChild): Handle {
	/* TODO: There is an edge case where if a child tab is moved from one tabbed panel to another without being destroyed */
	tabListenersMap.set(tab, {
		onclickTabListener(evt: MouseEvent): boolean {
			evt.preventDefault();
			setActiveTab(tabbed, tab);
			return true;
		},
		onclickTabCloseListener(evt: MouseEvent): boolean {
			evt.preventDefault();
			tab.close().then((result) => {
				/* while Maquette schedules a render on DOM events, close happens async, therefore we have to
				 * invalidate the tabbed when resolved, otherwise the tab panel won't reflect the actual
				 * children */
				if (result) {
					tabbed.invalidate();
				};
			});
			return true;
		}
	});
	return {
		destroy() {
			const tabListeners = tabListenersMap.get(tab);
			if (tabListeners) {
				tabListenersMap.delete(tab);
			}
		}
	};
}

		return new Promise((resolve) => {
			handlesWeakMap.get(this).forEach((handle) => {
				handle && handle.destroy && handle.destroy();
			});
			handlesWeakMap.delete(this);
			this.destroy = noop;
			this.own = destroyed;
			resolve(true);
		});

/**
 * A utility function that sets the listeners for a tab which are then passed in the generated VDom.  The function
 * returns a handle that can be used to clean up the listeners
 * @param tabbed The tabbed mixin that should be effected when the listeners fire
 * @param tab The tab that the listeners are referring to
 */
function setTabListeners(tabbed: TabbedMixin<TabbedChild, TabbedState>, tab: TabbedChild): Handle {
	/* TODO: There is an edge case where if a child tab is moved from one tabbed panel to another without being destroyed */
	tabListenersMap.set(tab, {
		onclickTabListener(evt: MouseEvent): boolean {
			evt.preventDefault();
			setActiveTab(tabbed, tab);
			return true;
		},
		onclickTabCloseListener(evt: MouseEvent): boolean {
			evt.preventDefault();
			/* TODO: actually close the tab */
			console.log('close');
			return;
		}
	});
	return {
		destroy() {
			const tabListeners = tabListenersMap.get(tab);
			if (tabListeners) {
				tabListenersMap.delete(tab);
			}
		}
	};
}

				}, (err) => { /* error handler */
					stateful.emit({
						type: 'error',
						target: stateful,
						error: err
					});
					unobserve(stateful);
				}, () => { /* completed handler */
					unobserve(stateful);
				}),
				handle: {
					destroy() {
						const observedState = observedStateMap.get(stateful);
						if (observedState) {
							observedState.subscription.unsubscribe();
							observedStateMap.delete(stateful);
						}
					}
				}
			};
			observedStateMap.set(stateful, observedState);
			return observedState.handle;
		}
	}, (instance: any, options: StatefulOptions<State>) => {
		const state = {};
		stateWeakMap.set(instance, state);
		if (options) {
			if (options.state) {
				instance.setState(options.state);
			}
			if (options.id && options.stateFrom) {

				tabbed.children.forEach((tab, key) => {
					const isActiveTab = tab === activeTab;
					if (isActiveTab || (childrenNodes[key] && childrenNodes[key].properties.classes['visible'])) {
						tab.invalidate();
						const tabVNode = tab.render();
						tabVNode.properties.classes['visible'] = isActiveTab;
						childrenNodes[key] = tabVNode;
					}
					/* else, this tab isn't active and hasn't been previously rendered */

					tabs.push(h(tabbed.tagNames.tab, { key: tab, classes: { active: isActiveTab } }, getTabChildVNode(tab)));
				});

				return [ h(tabbed.tagNames.tabBar, tabs), h('div.panels', childrenNodes) ];
			}
		}
	})
	.mixin({
		mixin: createDestroyable,
		initialize(instance: TabbedMixin<TabbedChild, TabbedState>) {
			instance.own({
				destroy() {
					childrenNodesCache.delete(instance);
				}
			});
		}
	}) as TabbedMixinFactory;

export default createTabbedMixin;