/**
 * Pushes pending state changes and client RPC calls to the client. If
 * {@code isConnected()} is false, defers the push until a connection is
 * established.
 *
 * @param async True if this push asynchronously originates from the server,
 *              false if it is a response to a client request.
 */
void push(boolean async) {
    if (!isConnected()) {
        if (async && state != State.RESPONSE_PENDING) {
            state = State.PUSH_PENDING;
        } else {
            state = State.RESPONSE_PENDING;
        }
    } else {
        try {
            UI ui = VaadinSession.getCurrent().getUIById(this.uiId);
            Writer writer = new StringWriter();
            new UidlWriter().write(ui, writer, async);
            sendMessage("for(;;);[{" + writer + "}]");
        } catch (Exception e) {
            throw new PushException("Push failed", e);
        }
    }
}
 

@Override
public String getMainDivId(VaadinSession session, VaadinRequest request, Class<? extends UI> uiClass) {
    String appId = request.getPathInfo();
    if (appId == null || "".equals(appId) || "/".equals(appId)) {
        appId = "ROOT";
    }
    appId = appId.replaceAll("[^a-zA-Z0-9]", "");
    // Add hashCode to the end, so that it is still (sort of)
    // predictable, but indicates that it should not be used in CSS
    // and
    // such:
    int hashCode = appId.hashCode();
    if (hashCode < 0) {
        hashCode = -hashCode;
    }
    appId = appId + "-" + hashCode;
    return appId;
}
 

public void setLocale(Locale locale) {
    UserSession session = getConnection().getSession();
    if (session != null) {
        session.setLocale(locale);
    }

    AppUI currentUi = AppUI.getCurrent();
    // it can be null if we handle request in a custom RequestHandler
    if (currentUi != null) {
        currentUi.setLocale(locale);
        currentUi.updateClientSystemMessages(locale);
    }

    VaadinSession.getCurrent().setLocale(locale);

    for (AppUI ui : getAppUIs()) {
        if (ui != currentUi) {
            ui.accessSynchronously(() -> {
                ui.setLocale(locale);
                ui.updateClientSystemMessages(locale);
            });
        }
    }
}
 

@Override
protected void initExpectations() {
    super.initExpectations();

    new Expectations() {
        {
            vaadinSession.getLocale(); result = Locale.ENGLISH; minTimes = 0;
            VaadinSession.getCurrent(); result = vaadinSession; minTimes = 0;

            vaadinSession.getConverterFactory(); result = new DefaultConverterFactory(); minTimes = 0;

            globalConfig.getAvailableLocales(); result = ImmutableMap.of("en", Locale.ENGLISH); minTimes = 0;
            AppContext.getProperty("cuba.mainMessagePack"); result = "com.haulmont.cuba.web"; minTimes = 0;
        }
    };

    this.uiComponents = new TestUiComponents(applicationContext);
}
 

@Override
protected void initExpectations() {
    super.initExpectations();

    new Expectations() {
        {
            vaadinSession.getLocale(); result = Locale.ENGLISH; minTimes = 0;
            VaadinSession.getCurrent(); result = vaadinSession; minTimes = 0;

            vaadinSession.getConverterFactory(); result = new DefaultConverterFactory(); minTimes = 0;

            globalConfig.getAvailableLocales(); result = ImmutableMap.of("en", Locale.ENGLISH); minTimes = 0;
            AppContext.getProperty("cuba.mainMessagePack"); result = "com.haulmont.cuba.web"; minTimes = 0;
        }
    };
}
 

@Override
protected void initExpectations() {
    super.initExpectations();

    new Expectations() {
        {
            vaadinSession.getLocale(); result = Locale.ENGLISH; minTimes = 0;
            VaadinSession.getCurrent(); result = vaadinSession; minTimes = 0;

            vaadinSession.getConverterFactory(); result = new DefaultConverterFactory(); minTimes = 0;

            globalConfig.getAvailableLocales(); result = ImmutableMap.of("en", Locale.ENGLISH); minTimes = 0;
            AppContext.getProperty("cuba.mainMessagePack"); result = "com.haulmont.cuba.web"; minTimes = 0;
        }
    };

    this.uiComponents = new TestUiComponents(applicationContext);
}
 

@Override
protected void initExpectations() {
    super.initExpectations();

    new Expectations() {
        {
            vaadinSession.getLocale(); result = Locale.ENGLISH; minTimes = 0;
            VaadinSession.getCurrent(); result = vaadinSession; minTimes = 0;

            vaadinSession.getConverterFactory(); result = new DefaultConverterFactory(); minTimes = 0;

            globalConfig.getAvailableLocales(); result = ImmutableMap.of("en", Locale.ENGLISH); minTimes = 0;
            AppContext.getProperty("cuba.mainMessagePack"); result = "com.haulmont.cuba.web"; minTimes = 0;
        }
    };

    this.uiComponents = new TestUiComponents(applicationContext);
}
 

@Override
protected void initExpectations() {
    super.initExpectations();

    new Expectations() {
        {
            vaadinSession.getLocale(); result = Locale.ENGLISH; minTimes = 0;
            VaadinSession.getCurrent(); result = vaadinSession; minTimes = 0;

            vaadinSession.getConverterFactory(); result = new DefaultConverterFactory(); minTimes = 0;

            globalConfig.getAvailableLocales(); result = ImmutableMap.of("en", Locale.ENGLISH); minTimes = 0;
            AppContext.getProperty("cuba.mainMessagePack"); result = "com.haulmont.cuba.web"; minTimes = 0;
        }
    };

    this.uiComponents = new TestUiComponents(applicationContext);
}
 

@Override
protected void initExpectations() {
    super.initExpectations();

    new Expectations() {
        {
            vaadinSession.getLocale(); result = Locale.ENGLISH; minTimes = 0;
            VaadinSession.getCurrent(); result = vaadinSession; minTimes = 0;

            globalConfig.getAvailableLocales(); result = ImmutableMap.of("en", Locale.ENGLISH); minTimes = 0;
            AppContext.getProperty("cuba.mainMessagePack"); result = "com.haulmont.cuba.web"; minTimes = 0;
        }
    };

    this.uiComponents = new TestUiComponents(applicationContext);
}
 

@Override
protected void initExpectations() {
    super.initExpectations();

    new Expectations() {
        {
            vaadinSession.getLocale(); result = Locale.ENGLISH; minTimes = 0;
            VaadinSession.getCurrent(); result = vaadinSession; minTimes = 0;

            vaadinSession.getConverterFactory(); result = new DefaultConverterFactory(); minTimes = 0;

            globalConfig.getAvailableLocales(); result = ImmutableMap.of("en", Locale.ENGLISH); minTimes = 0;
            AppContext.getProperty("cuba.mainMessagePack"); result = "com.haulmont.cuba.web"; minTimes = 0;
        }
    };

    this.uiComponents = new TestUiComponents(applicationContext);
}
 

@Override
protected void initExpectations() {
    super.initExpectations();

    new Expectations() {
        {
            vaadinSession.getLocale(); result = Locale.ENGLISH; minTimes = 0;
            VaadinSession.getCurrent(); result = vaadinSession; minTimes = 0;

            globalConfig.getAvailableLocales(); result = ImmutableMap.of("en", Locale.ENGLISH); minTimes = 0;
            AppContext.getProperty("cuba.mainMessagePack"); result = "com.haulmont.cuba.web"; minTimes = 0;
        }
    };

    this.uiComponents = new TestUiComponents(applicationContext);
}
 

@Override
protected void initExpectations() {
    super.initExpectations();

    new Expectations() {
        {
            vaadinSession.getLocale(); result = Locale.ENGLISH; minTimes = 0;
            VaadinSession.getCurrent(); result = vaadinSession; minTimes = 0;

            vaadinSession.getConverterFactory(); result = new DefaultConverterFactory(); minTimes = 0;

            globalConfig.getAvailableLocales(); result = ImmutableMap.of("en", Locale.ENGLISH); minTimes = 0;
            AppContext.getProperty("cuba.mainMessagePack"); result = "com.haulmont.cuba.web"; minTimes = 0;
        }
    };
    this.uiComponents = new TestUiComponents(applicationContext);
}
 

@Override
public void attach() {
    super.attach();

    service = createService();
    String url = service.getAuthorizationUrl(null);
    
    gplusLoginButton = new Link("Login with Google", new ExternalResource(url));
    gplusLoginButton.addStyleName(ValoTheme.LINK_LARGE);

    VaadinSession.getCurrent().addRequestHandler(this);

    setContent(new MVerticalLayout(gplusLoginButton).alignAll(
            Alignment.MIDDLE_CENTER).withFullHeight());
    setModal(true);
    setWidth("300px");
    setHeight("200px");

}
 

@Override
public boolean synchronizedHandleRequest(VaadinSession session, VaadinRequest request, VaadinResponse response) throws IOException {
  response.setContentType("text/css");

  byte[] text = generateCss();

  response.setCacheTime(-1);
  response.setStatus(HttpURLConnection.HTTP_OK);

  try (OutputStream stream = response.getOutputStream()) {
    response.setContentLength(text.length);
    stream.write(text);
  }

  return true;
}
 

/**
 * {@inheritDoc}
 */
public String getConversationId() {
	Integer uiId = null;
	
	UI ui =  UI.getCurrent();
	if (ui == null) {
		UIid id = CurrentInstance.get(UIid.class);
		if (id != null) {
			uiId = id.getUiId();
		}
	}
	else if (ui != null) {
		if (!sessions.containsKey(ui)) {
			ui.addDetachListener(this);
			sessions.put(ui, VaadinSession.getCurrent().getSession().getId());
		}

		uiId = ui.getUIId();
	}
	
	return uiId != null ? getConversationId(uiId) : null;
}
 

@Override
public boolean validate(String username, String password) {
	UsernamePasswordAuthenticationToken token = new UsernamePasswordAuthenticationToken(username, password);
	try {
		Authentication auth = this.authenticationManager.authenticate(token);
		if (auth.isAuthenticated()) {
			// execute session authentication strategy
			if (this.sessionStrategy != null)
				this.sessionStrategy.onAuthentication(auth, VaadinServletService.getCurrentServletRequest(),
						VaadinServletService.getCurrentResponse());
			SecurityContextHolder.getContext().setAuthentication(auth);
			// save request in context session
			VaadinSession.getCurrent().getSession().setAttribute(
					HttpSessionSecurityContextRepository.SPRING_SECURITY_CONTEXT_KEY,
					SecurityContextHolder.getContext());
			
			return  true;
		}
		SecurityContextHolder.clearContext();
		return false;
	}
	catch(AuthenticationException ae) {
		SecurityContextHolder.clearContext();
		return false;
	}
}
 

private void readUiFromEnclosingClass(JsonObject vaadinConfig) {
    Class<?> enclosingClass = getClass().getEnclosingClass();

    if (enclosingClass != null && UI.class.isAssignableFrom(enclosingClass)) {
        vaadinConfig.put(VaadinSession.UI_PARAMETER, enclosingClass.getName());
    }
}
 

/**
 * Call the session's {@link ErrorHandler}, if it has one, with the given
 * exception wrapped in an {@link ErrorEvent}.
 */
private void callErrorHandler(VaadinSession session, Exception e) {
    try {
        ErrorHandler errorHandler = ErrorEvent.findErrorHandler(session);
        if (errorHandler != null) {
            errorHandler.error(new ErrorEvent(e));
        }
    } catch (Exception ex) {
        // Let's not allow error handling to cause trouble; log fails
        logger.warn("ErrorHandler call failed", ex);
    }
}
 

protected WebBrowser getWebBrowserDetails() {
    // timezone info is passed only on VaadinSession creation
    WebBrowser webBrowser = VaadinSession.getCurrent().getBrowser();
    VaadinRequest currentRequest = VaadinService.getCurrentRequest();
    // update web browser instance if current request is not null
    // it can be null in case of background/async processing of login request
    if (currentRequest != null) {
        webBrowser.updateRequestDetails(currentRequest);
    }
    return webBrowser;
}
 

protected void setSessionInternal(@Nullable ClientUserSession userSession) {
    VaadinSession.getCurrent().setAttribute(UserSession.class, userSession);
    if (userSession != null) {
        AppContext.setSecurityContext(new SecurityContext(userSession));
    } else {
        AppContext.setSecurityContext(null);
    }
}
 

@Override
public Object get(String name, ObjectFactory<?> objectFactory) {
    VaadinSession session = VaadinSession.getCurrent();
    if (session == null || !session.hasLock()) {
        throw new IllegalStateException("Unable to use VaadinSessionScope from non-Vaadin thread");
    }

    Object object = session.getAttribute(name);
    if (object == null) {
        object = objectFactory.getObject();
        session.setAttribute(name, object);
    }
    return object;
}
 

@Override
public Object remove(String name) {
    VaadinSession session = VaadinSession.getCurrent();
    if (session == null || !session.hasLock()) {
        throw new IllegalStateException("Unable to use VaadinSessionScope from non-Vaadin thread");
    }

    Object bean = session.getAttribute(name);
    session.setAttribute(name, null);
    return bean;
}
 

@Override
public String getConversationId() {
    if (VaadinSession.getCurrent() == null || !VaadinSession.getCurrent().hasLock()) {
        throw new IllegalStateException("Unable to use VaadinSessionScope from non-Vaadin thread");
    }

    return VaadinSession.getCurrent().getSession().getId();
}
 

@Override
public SecurityContext get() {
    VaadinSession vaadinSession = VaadinSession.getCurrent();
    if (vaadinSession != null && vaadinSession.hasLock()) {
        return vaadinSession.getAttribute(SecurityContext.class);
    }

    return super.get();
}
 

@Override
public void set(SecurityContext securityContext) {
    VaadinSession vaadinSession = VaadinSession.getCurrent();
    if (vaadinSession != null && vaadinSession.hasLock()) {
        vaadinSession.setAttribute(SecurityContext.class, securityContext);
    } else {
        super.set(securityContext);
    }
}
 

public void clearCache() {
    VaadinSession session = VaadinSession.getCurrent();
    if (session == null || !session.hasLock()) {
        throw new IllegalConcurrentAccessException("Illegal access to settings client from background thread");
    }

    session.setAttribute(SettingsClient.NAME, null);
}
 

protected Map<String, Optional<String>> getCache() {
    VaadinSession session = VaadinSession.getCurrent();
    if (session == null || !session.hasLock()) {
        throw new IllegalConcurrentAccessException("Illegal access to settings client from background thread");
    }

    @SuppressWarnings("unchecked")
    Map<String, Optional<String>> settings = (Map<String, Optional<String>>) session.getAttribute(SettingsClient.NAME);
    if (settings == null) {
        settings = new HashMap<>();
        session.setAttribute(SettingsClient.NAME, settings);
    }
    return settings;
}
 

public List<AppUI> getAppUIs() {
    List<AppUI> list = new ArrayList<>();
    for (UI ui : VaadinSession.getCurrent().getUIs()) {
        if (ui instanceof AppUI)
            list.add((AppUI) ui);
        else
            log.warn("Invalid UI in the session: {}", ui);
    }
    return list;
}
 

/**
 * Called when <em>the first</em> UI of the session is initialized.
 */
protected void init(Locale requestLocale) {
    VaadinSession vSession = VaadinSession.getCurrent();
    vSession.setAttribute(App.class, this);

    vSession.setLocale(messageTools.getDefaultLocale());

    // set root error handler for all session
    vSession.setErrorHandler(event -> {
        try {
            getExceptionHandlers().handle(event);
            getAppLog().log(event);
        } catch (Throwable e) {
            log.error("Error handling exception\nOriginal exception:\n{}\nException in handlers:\n{}",
                    ExceptionUtils.getStackTrace(event.getThrowable()), ExceptionUtils.getStackTrace(e)
            );
        }
    });

    log.debug("Initializing application");

    appLog = new AppLog(webConfig.getAppLogMaxItemsCount(), beanLocator.get(TimeSource.NAME));

    connection = createConnection();
    exceptionHandlers = new ExceptionHandlers(this, beanLocator);
    cookies = new AppCookies();

    themeConstants = loadTheme();

    // get default locale from config
    Locale targetLocale = resolveLocale(requestLocale);
    setLocale(targetLocale);
}
 

/**
 * @return Current App instance. Can be invoked anywhere in application code.
 * @throws IllegalStateException if no application instance is bound to the current {@link VaadinSession}
 */
public static App getInstance() {
    VaadinSession vSession = VaadinSession.getCurrent();
    if (vSession == null) {
        throw new IllegalStateException("No VaadinSession found");
    }
    if (!vSession.hasLock()) {
        throw new IllegalStateException("VaadinSession is not owned by the current thread");
    }
    App app = vSession.getAttribute(App.class);
    if (app == null) {
        throw new IllegalStateException("No App is bound to the current VaadinSession");
    }
    return app;
}