/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

'use strict';

import 'vs/css!./media/workbench';

import { TPromise, ValueCallback } from 'vs/base/common/winjs.base';
import { IDisposable, dispose } from 'vs/base/common/lifecycle';
import Event, { Emitter } from 'vs/base/common/event';
import DOM = require('vs/base/browser/dom');
import { Builder, $ } from 'vs/base/browser/builder';
import { Delayer } from 'vs/base/common/async';
import * as browser from 'vs/base/browser/browser';
import assert = require('vs/base/common/assert');
import { StopWatch } from 'vs/base/common/stopwatch';
import errors = require('vs/base/common/errors');
import { BackupFileService } from 'vs/workbench/services/backup/node/backupFileService';
import { IBackupFileService } from 'vs/workbench/services/backup/common/backup';
import { toErrorMessage } from 'vs/base/common/errorMessage';
import { Registry } from 'vs/platform/platform';
import { isWindows, isLinux, isMacintosh } from 'vs/base/common/platform';
import { IOptions } from 'vs/workbench/common/options';
import { Position as EditorPosition } from 'vs/platform/editor/common/editor';
import { IWorkbenchContributionsRegistry, Extensions as WorkbenchExtensions } from 'vs/workbench/common/contributions';
import { BaseEditor } from 'vs/workbench/browser/parts/editor/baseEditor';
import { IEditorRegistry, Extensions as EditorExtensions, TextEditorOptions, EditorInput, EditorOptions } from 'vs/workbench/common/editor';
import { HistoryService } from 'vs/workbench/services/history/browser/history';
import { ActivitybarPart } from 'vs/workbench/browser/parts/activitybar/activitybarPart';
import { EditorPart } from 'vs/workbench/browser/parts/editor/editorPart';
import { SidebarPart } from 'vs/workbench/browser/parts/sidebar/sidebarPart';
import { PanelPart } from 'vs/workbench/browser/parts/panel/panelPart';
import { StatusbarPart } from 'vs/workbench/browser/parts/statusbar/statusbarPart';
import { TitlebarPart } from 'vs/workbench/browser/parts/titlebar/titlebarPart';
import { WorkbenchLayout } from 'vs/workbench/browser/layout';
import { IActionBarRegistry, Extensions as ActionBarExtensions } from 'vs/workbench/browser/actionBarRegistry';
import { PanelRegistry, Extensions as PanelExtensions } from 'vs/workbench/browser/panel';
import { QuickOpenController } from 'vs/workbench/browser/parts/quickopen/quickOpenController';
import { getServices } from 'vs/platform/instantiation/common/extensions';
import { IUntitledEditorService } from 'vs/workbench/services/untitled/common/untitledEditorService';
import { WorkbenchEditorService } from 'vs/workbench/services/editor/browser/editorService';
import { Position, Parts, IPartService, ILayoutOptions } from 'vs/workbench/services/part/common/partService';
import { IWorkspace, IWorkspaceContextService } from 'vs/platform/workspace/common/workspace';
import { IStorageService, StorageScope } from 'vs/platform/storage/common/storage';
import { ContextMenuService } from 'vs/workbench/services/contextview/electron-browser/contextmenuService';
import { WorkbenchKeybindingService } from 'vs/workbench/services/keybinding/electron-browser/keybindingService';
import { IConfigurationService } from 'vs/platform/configuration/common/configuration';
import { WorkspaceConfigurationService } from 'vs/workbench/services/configuration/node/configurationService';
import { IConfigurationEditingService } from 'vs/workbench/services/configuration/common/configurationEditing';
import { ConfigurationEditingService } from 'vs/workbench/services/configuration/node/configurationEditingService';
import { ContextKeyService } from 'vs/platform/contextkey/browser/contextKeyService';
import { IKeybindingService } from 'vs/platform/keybinding/common/keybinding';
import { ContextKeyExpr, RawContextKey, IContextKeyService, IContextKey } from 'vs/platform/contextkey/common/contextkey';
import { IActivityBarService } from 'vs/workbench/services/activity/common/activityBarService';
import { IViewletService } from 'vs/workbench/services/viewlet/browser/viewlet';
import { ViewletService } from 'vs/workbench/services/viewlet/browser/viewletService';
import { FileService } from 'vs/workbench/services/files/electron-browser/fileService';
import { IFileService } from 'vs/platform/files/common/files';
import { IConfigurationResolverService } from 'vs/workbench/services/configurationResolver/common/configurationResolver';
import { ConfigurationResolverService } from 'vs/workbench/services/configurationResolver/node/configurationResolverService';
import { IPanelService } from 'vs/workbench/services/panel/common/panelService';
import { ITitleService } from 'vs/workbench/services/title/common/titleService';
import { WorkbenchMessageService } from 'vs/workbench/services/message/browser/messageService';
import { IWorkbenchEditorService } from 'vs/workbench/services/editor/common/editorService';
import { IQuickOpenService } from 'vs/platform/quickOpen/common/quickOpen';
import { IEditorGroupService } from 'vs/workbench/services/group/common/groupService';
import { IHistoryService } from 'vs/workbench/services/history/common/history';
import { IInstantiationService } from 'vs/platform/instantiation/common/instantiation';
import { SyncDescriptor } from 'vs/platform/instantiation/common/descriptors';
import { TextFileService } from 'vs/workbench/services/textfile/electron-browser/textFileService';
import { ITextFileService } from 'vs/workbench/services/textfile/common/textfiles';
import { ISCMService } from 'vs/workbench/services/scm/common/scm';
import { SCMService } from 'vs/workbench/services/scm/common/scmService';
import { TextModelResolverService } from 'vs/workbench/services/textmodelResolver/common/textModelResolverService';
import { ITextModelResolverService } from 'vs/editor/common/services/resolverService';
import { ServiceCollection } from 'vs/platform/instantiation/common/serviceCollection';
import { ILifecycleService, ShutdownReason } from 'vs/platform/lifecycle/common/lifecycle';
import { IWindowService } from 'vs/platform/windows/common/windows';
import { IMessageService } from 'vs/platform/message/common/message';
import { IStatusbarService } from 'vs/platform/statusbar/common/statusbar';
import { IMenuService } from 'vs/platform/actions/common/actions';
import { MenuService } from 'vs/platform/actions/common/menuService';
import { IContextMenuService } from 'vs/platform/contextview/browser/contextView';
import { IEnvironmentService } from 'vs/platform/environment/common/environment';
import { ITelemetryService } from 'vs/platform/telemetry/common/telemetry';
import { IWindowConfiguration } from 'vs/workbench/electron-browser/common';

export const MessagesVisibleContext = new RawContextKey<boolean>('globalMessageVisible', false);
export const EditorsVisibleContext = new RawContextKey<boolean>('editorIsOpen', false);
export const InZenModeContext = new RawContextKey<boolean>('inZenMode', false);
export const NoEditorsVisibleContext: ContextKeyExpr = EditorsVisibleContext.toNegated();

interface WorkbenchParams {
	workspace?: IWorkspace;
	options: IOptions;
	serviceCollection: ServiceCollection;
}

export interface IWorkbenchStartedInfo {
	customKeybindingsCount: number;
	restoreViewletDuration: number;
	restoreEditorsDuration: number;
	pinnedViewlets: string[];
}

export interface IWorkbenchCallbacks {
	onServicesCreated?: () => void;
	onWorkbenchStarted?: (info: IWorkbenchStartedInfo) => void;
}

const Identifiers = {
	WORKBENCH_CONTAINER: 'workbench.main.container',
	TITLEBAR_PART: 'workbench.parts.titlebar',
	ACTIVITYBAR_PART: 'workbench.parts.activitybar',
	SIDEBAR_PART: 'workbench.parts.sidebar',
	PANEL_PART: 'workbench.parts.panel',
	EDITOR_PART: 'workbench.parts.editor',
	STATUSBAR_PART: 'workbench.parts.statusbar'
};

/**
 * The workbench creates and lays out all parts that make up the workbench.
 */
export class Workbench implements IPartService {

	private static sidebarHiddenSettingKey = 'workbench.sidebar.hidden';
	private static sidebarRestoreSettingKey = 'workbench.sidebar.restore';
	private static panelHiddenSettingKey = 'workbench.panel.hidden';

	private static sidebarPositionConfigurationKey = 'workbench.sideBar.location';
	private static statusbarVisibleConfigurationKey = 'workbench.statusBar.visible';
	private static activityBarVisibleConfigurationKey = 'workbench.activityBar.visible';

	private _onTitleBarVisibilityChange: Emitter<void>;

	public _serviceBrand: any;

	private parent: HTMLElement;
	private container: HTMLElement;
	private workbenchParams: WorkbenchParams;
	private workbenchContainer: Builder;
	private workbench: Builder;
	private workbenchStarted: boolean;
	private workbenchCreated: boolean;
	private workbenchShutdown: boolean;
	private editorService: WorkbenchEditorService;
	private viewletService: IViewletService;
	private contextKeyService: IContextKeyService;
	private keybindingService: IKeybindingService;
	private backupFileService: IBackupFileService;
	private configurationEditingService: IConfigurationEditingService;
	private titlebarPart: TitlebarPart;
	private activitybarPart: ActivitybarPart;
	private sidebarPart: SidebarPart;
	private panelPart: PanelPart;
	private editorPart: EditorPart;
	private statusbarPart: StatusbarPart;
	private quickOpen: QuickOpenController;
	private workbenchLayout: WorkbenchLayout;
	private toDispose: IDisposable[];
	private toShutdown: { shutdown: () => void; }[];
	private callbacks: IWorkbenchCallbacks;
	private creationPromise: TPromise<boolean>;
	private creationPromiseComplete: ValueCallback;
	private sideBarHidden: boolean;
	private statusBarHidden: boolean;
	private activityBarHidden: boolean;
	private sideBarPosition: Position;
	private panelHidden: boolean;
	private editorBackgroundDelayer: Delayer<void>;
	private messagesVisibleContext: IContextKey<boolean>;
	private editorsVisibleContext: IContextKey<boolean>;
	private inZenMode: IContextKey<boolean>;
	private hasFilesToCreateOpenOrDiff: boolean;
	private zenMode: {
		active: boolean;
		transitionedToFullScreen: boolean;
		wasSideBarVisible: boolean;
		wasPanelVisible: boolean;
	};

	constructor(
		parent: HTMLElement,
		container: HTMLElement,
		workspace: IWorkspace,
		options: IOptions,
		serviceCollection: ServiceCollection,
		@IInstantiationService private instantiationService: IInstantiationService,
		@IUntitledEditorService private untitledEditorService: IUntitledEditorService,
		@IWorkspaceContextService private contextService: IWorkspaceContextService,
		@IStorageService private storageService: IStorageService,
		@ILifecycleService private lifecycleService: ILifecycleService,
		@IMessageService private messageService: IMessageService,
		@IConfigurationService private configurationService: WorkspaceConfigurationService,
		@ITelemetryService private telemetryService: ITelemetryService,
		@IEnvironmentService private environmentService: IEnvironmentService,
		@IWindowService private windowService: IWindowService
	) {
		this.parent = parent;
		this.container = container;

		this.workbenchParams = {
			workspace: workspace,
			options,
			serviceCollection
		};

		this.hasFilesToCreateOpenOrDiff =
			(options.filesToCreate && options.filesToCreate.length > 0) ||
			(options.filesToOpen && options.filesToOpen.length > 0) ||
			(options.filesToDiff && options.filesToDiff.length > 0);

		this.toDispose = [];
		this.toShutdown = [];
		this.editorBackgroundDelayer = new Delayer<void>(50);

		this._onTitleBarVisibilityChange = new Emitter<void>();

		this.creationPromise = new TPromise<boolean>(c => {
			this.creationPromiseComplete = c;
		});
	}

	public get onTitleBarVisibilityChange(): Event<void> {
		return this._onTitleBarVisibilityChange.event;
	}

	/**
	 * Starts the workbench and creates the HTML elements on the container. A workbench can only be started
	 * once. Use the shutdown function to free up resources created by the workbench on startup.
	 */
	public startup(callbacks?: IWorkbenchCallbacks): void {
		assert.ok(!this.workbenchStarted, 'Can not start a workbench that was already started');
		assert.ok(!this.workbenchShutdown, 'Can not start a workbench that was shutdown');

		try {
			this.workbenchStarted = true;
			this.callbacks = callbacks;

			// Create Workbench
			this.createWorkbench();

			// Services
			this.initServices();
			if (this.callbacks && this.callbacks.onServicesCreated) {
				this.callbacks.onServicesCreated();
			}

			// Contexts
			this.messagesVisibleContext = MessagesVisibleContext.bindTo(this.contextKeyService);
			this.editorsVisibleContext = EditorsVisibleContext.bindTo(this.contextKeyService);
			this.inZenMode = InZenModeContext.bindTo(this.contextKeyService);

			// Register Listeners
			this.registerListeners();

			// Settings
			this.initSettings();

			// Create Workbench and Parts
			this.renderWorkbench();

			// Workbench Layout
			this.createWorkbenchLayout();

			// Load composits and editors in parallel
			const compositeAndEditorPromises: TPromise<any>[] = [];

			// Restore last opened viewlet
			let viewletRestoreStopWatch: StopWatch;
			if (!this.sideBarHidden) {
				let viewletIdToRestore: string;

				if (this.shouldRestoreLastOpenedViewlet()) {
					viewletIdToRestore = this.storageService.get(SidebarPart.activeViewletSettingsKey, StorageScope.WORKSPACE);
				}

				if (!viewletIdToRestore) {
					viewletIdToRestore = this.viewletService.getDefaultViewletId();
				}

				viewletRestoreStopWatch = StopWatch.create();
				compositeAndEditorPromises.push(this.viewletService.openViewlet(viewletIdToRestore).then(() => {
					viewletRestoreStopWatch.stop();
				}));
			}

			// Load Panel
			const panelRegistry = Registry.as<PanelRegistry>(PanelExtensions.Panels);
			const panelId = this.storageService.get(PanelPart.activePanelSettingsKey, StorageScope.WORKSPACE, panelRegistry.getDefaultPanelId());
			if (!this.panelHidden && !!panelId) {
				compositeAndEditorPromises.push(this.panelPart.openPanel(panelId, false));
			}

			// Load Editors
			const editorRestoreStopWatch = StopWatch.create();
			compositeAndEditorPromises.push(this.resolveEditorsToOpen().then(inputsWithOptions => {
				let editorOpenPromise: TPromise<BaseEditor[]>;
				if (inputsWithOptions.length) {
					const editors = inputsWithOptions.map(inputWithOptions => {
						return {
							input: inputWithOptions.input,
							options: inputWithOptions.options,
							position: EditorPosition.ONE
						};
					});

					editorOpenPromise = this.editorPart.openEditors(editors);
				} else {
					editorOpenPromise = this.editorPart.restoreEditors();
				}

				return editorOpenPromise.then(() => {
					this.onEditorsChanged(); // make sure we show the proper background in the editor area
					editorRestoreStopWatch.stop();
				});
			}));

			// Flag workbench as created once done
			const workbenchDone = (error?: Error) => {
				this.workbenchCreated = true;
				this.creationPromiseComplete(true);

				if (this.callbacks && this.callbacks.onWorkbenchStarted) {
					this.callbacks.onWorkbenchStarted({
						customKeybindingsCount: this.keybindingService.customKeybindingsCount(),
						restoreViewletDuration: viewletRestoreStopWatch ? viewletRestoreStopWatch.elapsed() : 0,
						restoreEditorsDuration: editorRestoreStopWatch.elapsed(),
						pinnedViewlets: this.activitybarPart.getPinned()
					});
				}

				if (error) {
					errors.onUnexpectedError(error);
				}
			};

			// Join viewlet, panel and editor promises
			TPromise.join(compositeAndEditorPromises).then(() => workbenchDone(), error => workbenchDone(error));
		} catch (error) {

			// Print out error
			console.error(toErrorMessage(error, true));

			// Rethrow
			throw error;
		}
	}

	private resolveEditorsToOpen(): TPromise<{ input: EditorInput, options?: EditorOptions }[]> {

		// Files to open, diff or create
		if (this.hasFilesToCreateOpenOrDiff) {
			const wbopt = this.workbenchParams.options;
			const filesToCreate = wbopt.filesToCreate || [];
			const filesToOpen = wbopt.filesToOpen || [];
			const filesToDiff = wbopt.filesToDiff;

			// Files to diff is exclusive
			if (filesToDiff && filesToDiff.length === 2) {
				return this.editorService.createInput({ leftResource: filesToDiff[0].resource, rightResource: filesToDiff[1].resource }).then(input => [{ input }]);
			}

			// Otherwise: Open/Create files
			else {
				const inputs: EditorInput[] = [];
				const options: EditorOptions[] = [];

				// Files to create
				inputs.push(...filesToCreate.map(resourceInput => this.untitledEditorService.createOrGet(resourceInput.resource)));
				options.push(...filesToCreate.map(r => null)); // fill empty options for files to create because we dont have options there

				// Files to open
				let filesToOpenInputPromise = filesToOpen.map(resourceInput => this.editorService.createInput(resourceInput));

				return TPromise.join<EditorInput>(filesToOpenInputPromise).then((inputsToOpen) => {
					inputs.push(...inputsToOpen);
					options.push(...filesToOpen.map(resourceInput => TextEditorOptions.from(resourceInput)));

					return inputs.map((input, index) => { return { input, options: options[index] }; });
				});
			}
		}

		// Empty workbench: some first time users will not have an untiled file; returning users will always have one
		else if (!this.workbenchParams.workspace && this.telemetryService.getExperiments().openUntitledFile) {
			return this.backupFileService.hasBackups().then(hasBackups => {
				if (hasBackups) {
					return TPromise.as([]); // do not open any empty untitled file if we have backups to restore
				}

				return TPromise.as([{ input: this.untitledEditorService.createOrGet() }]);
			});
		}

		return TPromise.as([]);
	}

	private initServices(): void {
		const {serviceCollection} = this.workbenchParams;

		this.toDispose.push(this.lifecycleService.onShutdown(this.shutdownComponents, this));

		// Services we contribute
		serviceCollection.set(IPartService, this);

		// Status bar
		this.statusbarPart = this.instantiationService.createInstance(StatusbarPart, Identifiers.STATUSBAR_PART);
		this.toDispose.push(this.statusbarPart);
		this.toShutdown.push(this.statusbarPart);
		serviceCollection.set(IStatusbarService, this.statusbarPart);

		// Keybindings
		this.contextKeyService = this.instantiationService.createInstance(ContextKeyService);
		serviceCollection.set(IContextKeyService, this.contextKeyService);

		this.keybindingService = this.instantiationService.createInstance(WorkbenchKeybindingService, window);
		serviceCollection.set(IKeybindingService, this.keybindingService);

		// Context Menu
		serviceCollection.set(IContextMenuService, new SyncDescriptor(ContextMenuService));

		// Menus/Actions
		serviceCollection.set(IMenuService, new SyncDescriptor(MenuService));

		// Title bar
		this.titlebarPart = this.instantiationService.createInstance(TitlebarPart, Identifiers.TITLEBAR_PART);
		this.toDispose.push(this.titlebarPart);
		this.toShutdown.push(this.titlebarPart);
		serviceCollection.set(ITitleService, this.titlebarPart);

		// Sidebar part
		this.sidebarPart = this.instantiationService.createInstance(SidebarPart, Identifiers.SIDEBAR_PART);
		this.toDispose.push(this.sidebarPart);
		this.toShutdown.push(this.sidebarPart);

		// Viewlet service
		this.viewletService = this.instantiationService.createInstance(ViewletService, this.sidebarPart);
		serviceCollection.set(IViewletService, this.viewletService);

		// Panel service (panel part)
		this.panelPart = this.instantiationService.createInstance(PanelPart, Identifiers.PANEL_PART);
		this.toDispose.push(this.panelPart);
		this.toShutdown.push(this.panelPart);
		serviceCollection.set(IPanelService, this.panelPart);

		// Activity service (activitybar part)
		this.activitybarPart = this.instantiationService.createInstance(ActivitybarPart, Identifiers.ACTIVITYBAR_PART);
		this.toDispose.push(this.activitybarPart);
		this.toShutdown.push(this.activitybarPart);
		serviceCollection.set(IActivityBarService, this.activitybarPart);

		// Editor service (editor part)
		this.editorPart = this.instantiationService.createInstance(EditorPart, Identifiers.EDITOR_PART, !this.hasFilesToCreateOpenOrDiff);
		this.toDispose.push(this.editorPart);
		this.toShutdown.push(this.editorPart);
		this.editorService = this.instantiationService.createInstance(WorkbenchEditorService, this.editorPart);
		serviceCollection.set(IWorkbenchEditorService, this.editorService);
		serviceCollection.set(IEditorGroupService, this.editorPart);

		// File Service
		const fileService = this.instantiationService.createInstance(FileService);
		serviceCollection.set(IFileService, fileService);
		this.toDispose.push(fileService.onFileChanges(e => this.configurationService.handleWorkspaceFileEvents(e)));

		// History
		serviceCollection.set(IHistoryService, new SyncDescriptor(HistoryService));

		// Backup File Service
		this.backupFileService = this.instantiationService.createInstance(BackupFileService);
		serviceCollection.set(IBackupFileService, this.backupFileService);

		// Text File Service
		serviceCollection.set(ITextFileService, new SyncDescriptor(TextFileService));

		// SCM Service
		serviceCollection.set(ISCMService, new SyncDescriptor(SCMService));

		// Text Model Resolver Service
		serviceCollection.set(ITextModelResolverService, new SyncDescriptor(TextModelResolverService));

		// Configuration Editing
		this.configurationEditingService = this.instantiationService.createInstance(ConfigurationEditingService);
		serviceCollection.set(IConfigurationEditingService, this.configurationEditingService);

		// Configuration Resolver
		const workspace = this.contextService.getWorkspace();
		serviceCollection.set(IConfigurationResolverService, new SyncDescriptor(ConfigurationResolverService, workspace ? workspace.resource : null, process.env));

		// Quick open service (quick open controller)
		this.quickOpen = this.instantiationService.createInstance(QuickOpenController);
		this.toDispose.push(this.quickOpen);
		this.toShutdown.push(this.quickOpen);
		serviceCollection.set(IQuickOpenService, this.quickOpen);

		// Contributed services
		const contributedServices = getServices();
		for (let contributedService of contributedServices) {
			serviceCollection.set(contributedService.id, contributedService.descriptor);
		}

		// Set the some services to registries that have been created eagerly
		Registry.as<IActionBarRegistry>(ActionBarExtensions.Actionbar).setInstantiationService(this.instantiationService);
		Registry.as<IWorkbenchContributionsRegistry>(WorkbenchExtensions.Workbench).setInstantiationService(this.instantiationService);
		Registry.as<IEditorRegistry>(EditorExtensions.Editors).setInstantiationService(this.instantiationService);
	}

	private initSettings(): void {

		// Sidebar visibility
		this.sideBarHidden = this.storageService.getBoolean(Workbench.sidebarHiddenSettingKey, StorageScope.WORKSPACE, false);
		if (!this.contextService.getWorkspace()) {
			this.sideBarHidden = true; // we hide sidebar in single-file-mode
		}

		// Panel part visibility
		const panelRegistry = Registry.as<PanelRegistry>(PanelExtensions.Panels);
		this.panelHidden = this.storageService.getBoolean(Workbench.panelHiddenSettingKey, StorageScope.WORKSPACE, true);
		if (!this.contextService.getWorkspace() || !panelRegistry.getDefaultPanelId()) {
			this.panelHidden = true; // we hide panel part in single-file-mode or if there is no default panel
		}

		// Sidebar position
		const sideBarPosition = this.configurationService.lookup<string>(Workbench.sidebarPositionConfigurationKey).value;
		this.sideBarPosition = (sideBarPosition === 'right') ? Position.RIGHT : Position.LEFT;

		// Statusbar visibility
		const statusBarVisible = this.configurationService.lookup<string>(Workbench.statusbarVisibleConfigurationKey).value;
		this.statusBarHidden = !statusBarVisible;

		// Activity bar visibility
		const activityBarVisible = this.configurationService.lookup<string>(Workbench.activityBarVisibleConfigurationKey).value;
		this.activityBarHidden = !activityBarVisible;

		// Zen mode
		this.zenMode = {
			active: false,
			transitionedToFullScreen: false,
			wasSideBarVisible: false,
			wasPanelVisible: false
		};
	}

	/**
	 * Returns whether the workbench has been started.
	 */
	public isStarted(): boolean {
		return this.workbenchStarted && !this.workbenchShutdown;
	}

	/**
	 * Returns whether the workbench has been fully created.
	 */
	public isCreated(): boolean {
		return this.workbenchCreated && this.workbenchStarted;
	}

	public joinCreation(): TPromise<boolean> {
		return this.creationPromise;
	}

	public hasFocus(part: Parts): boolean {
		const activeElement = document.activeElement;
		if (!activeElement) {
			return false;
		}

		const container = this.getContainer(part);
		return DOM.isAncestor(activeElement, container);
	}

	public getContainer(part: Parts): HTMLElement {
		let container: Builder = null;
		switch (part) {
			case Parts.TITLEBAR_PART:
				container = this.titlebarPart.getContainer();
				break;
			case Parts.ACTIVITYBAR_PART:
				container = this.activitybarPart.getContainer();
				break;
			case Parts.SIDEBAR_PART:
				container = this.sidebarPart.getContainer();
				break;
			case Parts.PANEL_PART:
				container = this.panelPart.getContainer();
				break;
			case Parts.EDITOR_PART:
				container = this.editorPart.getContainer();
				break;
			case Parts.STATUSBAR_PART:
				container = this.statusbarPart.getContainer();
				break;
		}
		return container && container.getHTMLElement();
	}

	public isVisible(part: Parts): boolean {
		switch (part) {
			case Parts.TITLEBAR_PART:
				return this.getCustomTitleBarStyle() && !browser.isFullscreen();
			case Parts.SIDEBAR_PART:
				return !this.sideBarHidden;
			case Parts.PANEL_PART:
				return !this.panelHidden;
			case Parts.STATUSBAR_PART:
				return !this.statusBarHidden;
			case Parts.ACTIVITYBAR_PART:
				return !this.activityBarHidden;
		}

		return true; // any other part cannot be hidden
	}

	public getTitleBarOffset(): number {
		let offset = 0;
		if (this.isVisible(Parts.TITLEBAR_PART)) {
			offset = 22 / browser.getZoomFactor(); // adjust the position based on title bar size and zoom factor
		}

		return offset;
	}

	private getCustomTitleBarStyle(): 'custom' {
		if (!isMacintosh) {
			return null; // custom title bar is only supported on Mac currently
		}

		const isDev = !this.environmentService.isBuilt || this.environmentService.isExtensionDevelopment;
		if (isDev) {
			return null; // not enabled when developing due to https://github.com/electron/electron/issues/3647
		}

		const windowConfig = this.configurationService.getConfiguration<IWindowConfiguration>();

		const style = windowConfig && windowConfig.window && windowConfig.window.titleBarStyle;

		if (style === 'custom') {
			return style;
		}

		return null;
	}

	private setStatusBarHidden(hidden: boolean, skipLayout?: boolean): void {
		this.statusBarHidden = hidden;


		// Layout
		if (!skipLayout) {
			this.workbenchLayout.layout({ forceStyleRecompute: true });
		}
	}

	public setActivityBarHidden(hidden: boolean, skipLayout?: boolean): void {
		this.activityBarHidden = hidden;


		// Layout
		if (!skipLayout) {
			this.workbenchLayout.layout({ forceStyleRecompute: true });
		}
	}

	public setSideBarHidden(hidden: boolean, skipLayout?: boolean): void {
		this.sideBarHidden = hidden;

		// Adjust CSS
		if (hidden) {
			this.workbench.addClass('nosidebar');
		} else {
			this.workbench.removeClass('nosidebar');
		}

		// Layout
		if (!skipLayout) {
			this.workbenchLayout.layout({ forceStyleRecompute: true });
		}

		// If sidebar becomes hidden, also hide the current active Viewlet if any
		if (hidden && this.sidebarPart.getActiveViewlet()) {
			this.sidebarPart.hideActiveViewlet();

			const activeEditor = this.editorPart.getActiveEditor();
			const activePanel = this.panelPart.getActivePanel();

			// Pass Focus to Editor or Panel if Sidebar is now hidden
			if (this.hasFocus(Parts.PANEL_PART) && activePanel) {
				activePanel.focus();
			} else if (activeEditor) {
				activeEditor.focus();
			}
		}

		// If sidebar becomes visible, show last active Viewlet or default viewlet
		else if (!hidden && !this.sidebarPart.getActiveViewlet()) {
			const viewletToOpen = this.sidebarPart.getLastActiveViewletId() || this.viewletService.getDefaultViewletId();
			if (viewletToOpen) {
				this.sidebarPart.openViewlet(viewletToOpen, true).done(null, errors.onUnexpectedError);
			}
		}

		// Remember in settings
		this.storageService.store(Workbench.sidebarHiddenSettingKey, hidden ? 'true' : 'false', StorageScope.WORKSPACE);
	}

	public setPanelHidden(hidden: boolean, skipLayout?: boolean): void {
		this.panelHidden = hidden;

		// Adjust CSS
		if (hidden) {
			this.workbench.addClass('nopanel');
		} else {
			this.workbench.removeClass('nopanel');
		}

		// Layout
		if (!skipLayout) {
			this.workbenchLayout.layout({ forceStyleRecompute: true });
		}

		// If panel part becomes hidden, also hide the current active panel if any
		if (hidden && this.panelPart.getActivePanel()) {
			this.panelPart.hideActivePanel();

			// Pass Focus to Editor if Panel part is now hidden
			const editor = this.editorPart.getActiveEditor();
			if (editor) {
				editor.focus();
			}
		}

		// If panel part becomes visible, show last active panel or default panel
		else if (!hidden && !this.panelPart.getActivePanel()) {
			const registry = Registry.as<PanelRegistry>(PanelExtensions.Panels);
			const panelToOpen = this.panelPart.getLastActivePanelId() || registry.getDefaultPanelId();
			if (panelToOpen) {
				this.panelPart.openPanel(panelToOpen, true).done(null, errors.onUnexpectedError);
			}
		}

		// Remember in settings
		this.storageService.store(Workbench.panelHiddenSettingKey, hidden ? 'true' : 'false', StorageScope.WORKSPACE);
	}

	public toggleMaximizedPanel(): void {
		this.workbenchLayout.layout({ forceStyleRecompute: true, toggleMaximizedPanel: true });
	}

	public getSideBarPosition(): Position {
		return this.sideBarPosition;
	}

	private setSideBarPosition(position: Position): void {
		if (this.sideBarHidden) {
			this.setSideBarHidden(false, true /* Skip Layout */);
		}

		const newPositionValue = (position === Position.LEFT) ? 'left' : 'right';
		const oldPositionValue = (this.sideBarPosition === Position.LEFT) ? 'left' : 'right';
		this.sideBarPosition = position;

		// Adjust CSS
		this.activitybarPart.getContainer().removeClass(oldPositionValue);
		this.sidebarPart.getContainer().removeClass(oldPositionValue);
		this.activitybarPart.getContainer().addClass(newPositionValue);
		this.sidebarPart.getContainer().addClass(newPositionValue);

		// Layout
		this.workbenchLayout.layout({ forceStyleRecompute: true });
	}

	public dispose(): void {
		if (this.isStarted()) {
			this.shutdownComponents();
			this.workbenchShutdown = true;
		}

		this.toDispose = dispose(this.toDispose);
	}

	/**
	 * Asks the workbench and all its UI components inside to lay out according to
	 * the containers dimension the workbench is living in.
	 */
	public layout(options?: ILayoutOptions): void {
		if (this.isStarted()) {
			this.workbenchLayout.layout(options);
		}
	}

	private shutdownComponents(reason = ShutdownReason.QUIT): void {

		// Restore sidebar if we are being shutdown as a matter of a reload
		if (reason === ShutdownReason.RELOAD) {
			this.storageService.store(Workbench.sidebarRestoreSettingKey, 'true', StorageScope.WORKSPACE);
		}

		// Pass shutdown on to each participant
		this.toShutdown.forEach(s => s.shutdown());
	}

	private registerListeners(): void {

		// Listen to editor changes
		this.toDispose.push(this.editorPart.onEditorsChanged(() => this.onEditorsChanged()));

		// Handle message service and quick open events
		this.toDispose.push((<WorkbenchMessageService>this.messageService).onMessagesShowing(() => this.messagesVisibleContext.set(true)));
		this.toDispose.push((<WorkbenchMessageService>this.messageService).onMessagesCleared(() => this.messagesVisibleContext.reset()));

		this.toDispose.push(this.quickOpen.onShow(() => (<WorkbenchMessageService>this.messageService).suspend())); // when quick open is open, don't show messages behind
		this.toDispose.push(this.quickOpen.onHide(() => (<WorkbenchMessageService>this.messageService).resume()));  // resume messages once quick open is closed again

		// Configuration changes
		this.toDispose.push(this.configurationService.onDidUpdateConfiguration(() => this.onDidUpdateConfiguration()));

		// Fullscreen changes
		this.toDispose.push(browser.onDidChangeFullscreen(() => this.onFullscreenChanged()));
	}

	private onFullscreenChanged(): void {
		if (!this.isCreated) {
			return; // we need to be ready
		}

		// Apply as CSS class
		const isFullscreen = browser.isFullscreen();
		if (isFullscreen) {
			this.addClass('fullscreen');
		} else {
			this.removeClass('fullscreen');
			if (this.zenMode.transitionedToFullScreen && this.zenMode.active) {
				this.toggleZenMode();
			}
		}

		// Changing fullscreen state of the window has an impact on custom title bar visibility, so we need to update
		const hasCustomTitle = this.getCustomTitleBarStyle() === 'custom';
		if (hasCustomTitle) {
			this._onTitleBarVisibilityChange.fire();
			this.layout(); // handle title bar when fullscreen changes
		}
	}

	private onEditorsChanged(): void {
		const visibleEditors = this.editorService.getVisibleEditors().length;

		// We update the editorpart class to indicate if an editor is opened or not
		// through a delay to accomodate for fast editor switching

		const editorContainer = this.editorPart.getContainer();
		if (visibleEditors === 0) {
			this.editorsVisibleContext.reset();
			this.editorBackgroundDelayer.trigger(() => editorContainer.addClass('empty'));
		} else {
			this.editorsVisibleContext.set(true);
			this.editorBackgroundDelayer.trigger(() => editorContainer.removeClass('empty'));
		}
	}

	private onDidUpdateConfiguration(skipLayout?: boolean): void {
		const newSidebarPositionValue = this.configurationService.lookup<string>(Workbench.sidebarPositionConfigurationKey).value;
		const newSidebarPosition = (newSidebarPositionValue === 'right') ? Position.RIGHT : Position.LEFT;
		if (newSidebarPosition !== this.getSideBarPosition()) {
			this.setSideBarPosition(newSidebarPosition);
		}

		if (!this.zenMode.active) {
			const newStatusbarHiddenValue = !this.configurationService.lookup<boolean>(Workbench.statusbarVisibleConfigurationKey).value;
			if (newStatusbarHiddenValue !== this.statusBarHidden) {
				this.setStatusBarHidden(newStatusbarHiddenValue, skipLayout);
			}

			const newActivityBarHiddenValue = !this.configurationService.lookup<boolean>(Workbench.activityBarVisibleConfigurationKey).value;
			if (newActivityBarHiddenValue !== this.activityBarHidden) {
				this.setActivityBarHidden(newActivityBarHiddenValue, skipLayout);
			}
		}
	}

	private createWorkbenchLayout(): void {
		this.workbenchLayout = this.instantiationService.createInstance(WorkbenchLayout,
			$(this.container),							// Parent
			this.workbench,								// Workbench Container
			{
				titlebar: this.titlebarPart,			// Title Bar
				activitybar: this.activitybarPart,		// Activity Bar
				editor: this.editorPart,				// Editor
				sidebar: this.sidebarPart,				// Sidebar
				panel: this.panelPart,					// Panel Part
				statusbar: this.statusbarPart,			// Statusbar
			},
			this.quickOpen								// Quickopen
		);

		this.toDispose.push(this.workbenchLayout);
	}

	private createWorkbench(): void {

		// Create Workbench DIV Off-DOM
		this.workbenchContainer = $('.monaco-workbench-container');
		this.workbench = $().div({ 'class': 'monaco-workbench ' + (isWindows ? 'windows' : isLinux ? 'linux' : 'mac'), id: Identifiers.WORKBENCH_CONTAINER }).appendTo(this.workbenchContainer);
	}

	private renderWorkbench(): void {

		// Apply sidebar state as CSS class
		if (this.sideBarHidden) {
			this.workbench.addClass('nosidebar');
		}
		if (this.panelHidden) {
			this.workbench.addClass('nopanel');
		}

		// Apply no-workspace state as CSS class
		if (!this.workbenchParams.workspace) {
			this.workbench.addClass('no-workspace');
		}

		// Apply title style if shown
		const titleStyle = this.getCustomTitleBarStyle();
		if (titleStyle) {
			DOM.addClass(this.parent, `titlebar-style-${titleStyle}`);
		}

		// Apply fullscreen state
		if (browser.isFullscreen()) {
			this.workbench.addClass('fullscreen');
		}

		// Create Parts
		this.createTitlebarPart();
		this.createActivityBarPart();
		this.createSidebarPart();
		this.createEditorPart();
		this.createPanelPart();
		this.createStatusbarPart();

		// Add Workbench to DOM
		this.workbenchContainer.build(this.container);
	}

	private createTitlebarPart(): void {
		const titlebarContainer = $(this.workbench).div({
			'class': ['part', 'titlebar'],
			id: Identifiers.TITLEBAR_PART,
			role: 'contentinfo'
		});

		this.titlebarPart.create(titlebarContainer);
	}

	private createActivityBarPart(): void {
		const activitybarPartContainer = $(this.workbench)
			.div({
				'class': ['part', 'activitybar', this.sideBarPosition === Position.LEFT ? 'left' : 'right'],
				id: Identifiers.ACTIVITYBAR_PART,
				role: 'navigation'
			});

		this.activitybarPart.create(activitybarPartContainer);
	}

	private createSidebarPart(): void {
		const sidebarPartContainer = $(this.workbench)
			.div({
				'class': ['part', 'sidebar', this.sideBarPosition === Position.LEFT ? 'left' : 'right'],
				id: Identifiers.SIDEBAR_PART,
				role: 'complementary'
			});

		this.sidebarPart.create(sidebarPartContainer);
	}

	private createPanelPart(): void {
		const panelPartContainer = $(this.workbench)
			.div({
				'class': ['part', 'panel', 'monaco-editor-background'],
				id: Identifiers.PANEL_PART,
				role: 'complementary'
			});

		this.panelPart.create(panelPartContainer);
	}

	private createEditorPart(): void {
		const editorContainer = $(this.workbench)
			.div({
				'class': ['part', 'editor', 'monaco-editor-background', 'empty'],
				id: Identifiers.EDITOR_PART,
				role: 'main'
			});

		this.editorPart.create(editorContainer);
	}

	private createStatusbarPart(): void {
		const statusbarContainer = $(this.workbench).div({
			'class': ['part', 'statusbar'],
			id: Identifiers.STATUSBAR_PART,
			role: 'contentinfo'
		});

		this.statusbarPart.create(statusbarContainer);
	}

	public getEditorPart(): EditorPart {
		assert.ok(this.workbenchStarted, 'Workbench is not started. Call startup() first.');

		return this.editorPart;
	}

	public getSidebarPart(): SidebarPart {
		assert.ok(this.workbenchStarted, 'Workbench is not started. Call startup() first.');

		return this.sidebarPart;
	}

	public getPanelPart(): PanelPart {
		assert.ok(this.workbenchStarted, 'Workbench is not started. Call startup() first.');

		return this.panelPart;
	}

	public getInstantiationService(): IInstantiationService {
		assert.ok(this.workbenchStarted, 'Workbench is not started. Call startup() first.');

		return this.instantiationService;
	}

	public addClass(clazz: string): void {
		if (this.workbench) {
			this.workbench.addClass(clazz);
		}
	}

	public removeClass(clazz: string): void {
		if (this.workbench) {
			this.workbench.removeClass(clazz);
		}
	}

	public getWorkbenchElementId(): string {
		return Identifiers.WORKBENCH_CONTAINER;
	}

	public toggleZenMode(): void {
		this.zenMode.active = !this.zenMode.active;
		// Check if zen mode transitioned to full screen and if now we are out of zen mode -> we need to go out of full screen
		let toggleFullScreen = false;
		if (this.zenMode.active) {
			const windowConfig = this.configurationService.getConfiguration<IWindowConfiguration>();
			toggleFullScreen = !browser.isFullscreen() && windowConfig.window.fullScreenZenMode;
			this.zenMode.transitionedToFullScreen = toggleFullScreen;
			this.zenMode.wasSideBarVisible = this.isVisible(Parts.SIDEBAR_PART);
			this.zenMode.wasPanelVisible = this.isVisible(Parts.PANEL_PART);
			this.setPanelHidden(true, true);
			this.setSideBarHidden(true, true);
			this.setActivityBarHidden(true, true);
			this.setStatusBarHidden(true, true);
		} else {
			if (this.zenMode.wasPanelVisible) {
				this.setPanelHidden(false, true);
			}
			if (this.zenMode.wasSideBarVisible) {
				this.setSideBarHidden(false, true);
			}
			// Status bar and activity bar visibility come from settings -> update their visibility.
			this.onDidUpdateConfiguration(true);
			const activeEditor = this.editorPart.getActiveEditor();
			if (activeEditor) {
				activeEditor.focus();
			}
			toggleFullScreen = this.zenMode.transitionedToFullScreen && browser.isFullscreen();
		}
		this.inZenMode.set(this.zenMode.active);

		this.layout();
		if (toggleFullScreen) {
			this.windowService.toggleFullScreen().done(undefined, errors.onUnexpectedError);
		}
	}

	private shouldRestoreLastOpenedViewlet(): boolean {
		if (!this.environmentService.isBuilt) {
			return true; // always restore sidebar when we are in development mode
		}

		const restore = this.storageService.getBoolean(Workbench.sidebarRestoreSettingKey, StorageScope.WORKSPACE);
		if (restore) {
			this.storageService.remove(Workbench.sidebarRestoreSettingKey, StorageScope.WORKSPACE); // only support once
		}

		return restore;
	}
}
