package org.argeo.cms.e4.rap;
   
   import java.security.AccessController;
   
   import javax.security.auth.Subject;
   import javax.security.auth.login.LoginContext;
   import javax.security.auth.login.LoginException;
   
   import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.argeo.api.NodeConstants;
  import org.argeo.cms.CmsException;
  import org.argeo.cms.auth.CurrentUser;
  import org.argeo.cms.ui.CmsImageManager;
  import org.argeo.cms.ui.CmsView;
  import org.argeo.cms.ui.UxContext;
  import org.argeo.cms.ui.dialogs.CmsFeedback;
  import org.argeo.cms.ui.util.SimpleImageManager;
  import org.argeo.cms.ui.util.SimpleUxContext;
  import org.argeo.cms.ui.widgets.auth.CmsLoginShell;
  import org.argeo.eclipse.ui.specific.UiContext;
  import org.eclipse.e4.core.services.events.IEventBroker;
  import org.eclipse.e4.ui.workbench.UIEvents;
  import org.eclipse.e4.ui.workbench.lifecycle.PostContextCreate;
  import org.eclipse.e4.ui.workbench.lifecycle.PreSave;
  import org.eclipse.rap.rwt.RWT;
  import org.eclipse.rap.rwt.client.service.BrowserNavigation;
  import org.eclipse.rap.rwt.client.service.BrowserNavigationEvent;
  import org.eclipse.rap.rwt.client.service.BrowserNavigationListener;
  import org.eclipse.swt.widgets.Display;
  import org.osgi.service.event.Event;
  import org.osgi.service.event.EventHandler;
  
  @SuppressWarnings("restriction")
  public class CmsLoginLifecycle implements CmsView {
  	private final static Log log = LogFactory.getLog(CmsLoginLifecycle.class);
  
  	private UxContext uxContext;
  	private CmsImageManager imageManager;
  
  	private LoginContext loginContext;
  	private BrowserNavigation browserNavigation;
  
  	private String state = null;
  
  	@PostContextCreate
  	boolean login(final IEventBroker eventBroker) {
  		browserNavigation = RWT.getClient().getService(BrowserNavigation.class);
  		if (browserNavigation != null)
  			browserNavigation.addBrowserNavigationListener(new BrowserNavigationListener() {
  				private static final long serialVersionUID = -3668136623771902865L;
  
  				@Override
  				public void navigated(BrowserNavigationEvent event) {
  					state = event.getState();
  					if (uxContext != null)// is logged in
  						stateChanged();
  				}
  			});
  
  		Subject subject = Subject.getSubject(AccessController.getContext());
  		Display display = Display.getCurrent();
  		UiContext.setData(CmsView.KEY, this);
  		CmsLoginShell loginShell = new CmsLoginShell(this);
  		loginShell.setSubject(subject);
  		try {
  			// try pre-auth
  			loginContext = new LoginContext(NodeConstants.LOGIN_CONTEXT_USER, subject, loginShell);
  			loginContext.login();
  		} catch (LoginException e) {
  			loginShell.createUi();
  			loginShell.open();
  
  			while (!loginShell.getShell().isDisposed()) {
  				if (!display.readAndDispatch())
  					display.sleep();
  			}
  		}
  		if (CurrentUser.getUsername(getSubject()) == null)
  			return false;
  		uxContext = new SimpleUxContext();
  		imageManager = new SimpleImageManager();
  
  		eventBroker.subscribe(UIEvents.UILifeCycle.APP_STARTUP_COMPLETE, new EventHandler() {
  			@Override
  			public void handleEvent(Event event) {
  				startupComplete();
  				eventBroker.unsubscribe(this);
  			}
  		});
  
  		// lcs.changeApplicationLocale(Locale.FRENCH);
  		return true;
  	}
  
  	@PreSave
  	void destroy() {
  		// logout();
  	}
 
 	@Override
 	public UxContext getUxContext() {
 		return uxContext;
 	}
 
 	@Override
 	public void navigateTo(String state) {
 		browserNavigation.pushState(state, state);
 	}
 
 	@Override
 	public void authChange(LoginContext loginContext) {
 		if (loginContext == null)
 			throw new CmsException("Login context cannot be null");
 		// logout previous login context
 		// if (this.loginContext != null)
 		// try {
 		// this.loginContext.logout();
 		// } catch (LoginException e1) {
 		// System.err.println("Could not log out: " + e1);
 		// }
 		this.loginContext = loginContext;
 	}
 
 	@Override
 	public void logout() {
 		if (loginContext == null)
 			throw new CmsException("Login context should not be null");
 		try {
 			CurrentUser.logoutCmsSession(loginContext.getSubject());
 			loginContext.logout();
 		} catch (LoginException e) {
 			throw new CmsException("Cannot log out", e);
 		}
 	}
 
 	@Override
 	public void exception(Throwable e) {
 		String msg = "Unexpected exception in Eclipse 4 RAP";
 		log.error(msg, e);
 		CmsFeedback.show(msg, e);
 	}
 
 	@Override
 	public CmsImageManager getImageManager() {
 		return imageManager;
 	}
 
 	protected Subject getSubject() {
 		return loginContext.getSubject();
 	}
 
 	@Override
 	public boolean isAnonymous() {
 		return CurrentUser.isAnonymous(getSubject());
 	}
 
 	// CALLBACKS
 	protected void startupComplete() {
 	}
 
 	protected void stateChanged() {
 
 	}
 
 	// GETTERS
 	protected BrowserNavigation getBrowserNavigation() {
 		return browserNavigation;
 	}
 
 	protected String getState() {
 		return state;
 	}
 
 }