EDIT

/**

* Copyright (C) 2017 EDIT

* European Distributed Institute of Taxonomy

* http://www.e-taxonomy.eu

*

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.cdm.addon.config;

import java.io.IOException;

import java.util.Arrays;

import java.util.Properties;

import javax.servlet.annotation.WebServlet;

import org.apache.log4j.Logger;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.ComponentScan;

import org.springframework.context.annotation.ComponentScan.Filter;

import org.springframework.context.annotation.Configuration;

import org.springframework.context.annotation.FilterType;

import org.springframework.context.annotation.Lazy;

import com.vaadin.server.DeploymentConfiguration;

import com.vaadin.server.ServiceException;

import com.vaadin.server.VaadinServletService;

import com.vaadin.spring.annotation.EnableVaadin;

import com.vaadin.spring.annotation.SpringUI;

import com.vaadin.spring.annotation.UIScope;

import com.vaadin.spring.server.SpringVaadinServlet;

import com.vaadin.ui.UI;

import eu.etaxonomy.cdm.common.ConfigFileUtil;

import eu.etaxonomy.cdm.opt.config.DataSourceConfigurer;

import eu.etaxonomy.cdm.vaadin.security.annotation.EnableAnnotationBasedAccessControl;

import eu.etaxonomy.cdm.vaadin.server.CdmSpringVaadinServletService;

import eu.etaxonomy.cdm.vaadin.ui.ConceptRelationshipUI;

import eu.etaxonomy.cdm.vaadin.ui.DistributionStatusUI;

import eu.etaxonomy.cdm.vaadin.ui.InactiveUIException;

import eu.etaxonomy.cdm.vaadin.ui.RegistrationUI;

import eu.etaxonomy.cdm.vaadin.ui.StatusEditorUI;

import eu.etaxonomy.vaadin.ui.annotation.EnableVaadinSpringNavigation;

/**

 *

 * @author a.kohlbecker

 * @since Feb 8, 2017

 *

 */

@Configuration

@ComponentScan(basePackages={

        "eu.etaxonomy.vaadin.ui",

        "eu.etaxonomy.cdm.vaadin",

        "eu.etaxonomy.cdm.dataInserter",

        "eu.etaxonomy.cdm.service",

        "eu.etaxonomy.cdm.vaadin.component", // for the FieldFactories

        "org.springframework.context.event"

        },

        // exclude UI classes, these are provided via the @Bean annotated methods below

        excludeFilters={@Filter(

                pattern="eu\\.etaxonomy\\.cdm\\.vaadin\\.ui\\..*",

                type=FilterType.REGEX

                )

            })

@EnableVaadin   // this imports VaadinConfiguration

@EnableVaadinSpringNavigation // activate the NavigationManagerBean

@EnableAnnotationBasedAccessControl // enable annotation based per view access control

public class CdmVaadinConfiguration {

    /**

     *

     */

    private static final String CDM_VAADIN_UI_ACTIVATED = "cdm-vaadin.ui.activated";

    public static final Logger logger = Logger.getLogger(CdmVaadinConfiguration.class);

    @Autowired

    @Lazy

    //FIXME consider to set the instanceName (instanceID) in the spring environment to avoid a bean reference here

    private DataSourceConfigurer dataSourceConfigurer;

    /*

     * NOTE: It is necessary to map the URLs starting with /VAADIN/* since none of the

     * @WebServlets is mapped to the root path. It is sufficient to configure one of the

     * servlets with this path see BookOfVaadin 5.9.5. Servlet Mapping with URL Patterns

     */

    @WebServlet(value = {"/app/*", "/VAADIN/*"}, asyncSupported = true)

    public static class Servlet extends SpringVaadinServlet {

        private static final long serialVersionUID = -2615042297393028775L;

        @Override

        protected VaadinServletService createServletService(

                DeploymentConfiguration deploymentConfiguration)

                throws ServiceException {

            //  - The SpringVaadinServletService is needed when using a custom service URL

            //  - The CdmSpringVaadinServletService allows to attach listeners to the requestEnd and 

            //    requestStart method this is important for proper unbinding of Conversations from 

            //    the request threads.

            //    see ViewScopeConversationHolder

            CdmSpringVaadinServletService service = new CdmSpringVaadinServletService(

                    this, deploymentConfiguration, getServiceUrlPath());

            service.init();

            return service;

        }

        /**

         *

        @SuppressWarnings("serial")

        @Override

        protected void servletInitialized() throws ServletException {

            getService().addSessionInitListener(new SessionInitListener() {

                @Override

                public void sessionInit(SessionInitEvent sessionInitEvent) throws ServiceException {

                    VaadinSession session = sessionInitEvent.getSession();

                    session.setErrorHandler(new DefaultErrorHandler(){

                        @Override

                        public void error(ErrorEvent errorEvent) {

                            if(errorEvent.getThrowable() instanceof InactiveUIException){

                                //TODO redirect to an ErrorUI or show and error Page

                                // better use Spring MVC Error handlers instead?

                            } else {

                                doDefault(errorEvent);

                            }

                        }

                    });

                }});

        }

         */

    }

    public CdmVaadinConfiguration() {

        logger.debug("CdmVaadinConfiguration enabled");

    }

    @Bean

    @UIScope

    public ConceptRelationshipUI conceptRelationshipUI() throws InactiveUIException {

        if(isUIEnabled(ConceptRelationshipUI.class)){

            return new ConceptRelationshipUI();

        }

        return null;

    }

    @Bean

    @UIScope

    public RegistrationUI registrationUI() throws InactiveUIException {

        if(isUIEnabled(RegistrationUI.class)){

            return new RegistrationUI();

        }

        return null;

    }

    @Bean

    @UIScope

    public DistributionStatusUI distributionStatusUI() throws InactiveUIException {

        if(isUIEnabled(DistributionStatusUI.class)){

            return new DistributionStatusUI();

        }

        return null;

    }

    @Bean

    @UIScope

    public StatusEditorUI statusEditorUI() throws InactiveUIException {

        if(isUIEnabled(StatusEditorUI.class)){

            return new StatusEditorUI();

        }

        return null;

    }

    static final String PROPERTIES_NAME = "vaadin-apps";

    private Properties appProps = null;

    //@formatter:off

    private static final String APP_FILE_CONTENT=

            "########################################################\n"+

            "#                                                       \n"+

            "# Vaadin application specific configurations            \n"+

            "#                                                       \n"+

            "########################################################\n"+

            "                                                        \n"+

            "# Enablement of vaadin uis.                             \n"+

            "#                                                       \n"+

            "# Multiple uis can be defined as comma separated list.  \n"+

            "# Whitespace before and after the comma will be ignored.\n"+

            "# Valid values are the path properties of the @SpringUI \n"+

            "# annotation which is used for UI classes.              \n"+

            "cdm-vaadin.ui.activated=concept,distribution,editstatus \n";

    //@formatter:on

    /**

     * Checks if the ui class supplied is activated by listing it in the properties by its {@link SpringUI#path()} value.

     *

     * @param type

     * @return

     * @throws InactiveUIException

     */

    private boolean isUIEnabled(Class<? extends UI>uiClass) throws InactiveUIException {

        String path = uiClass.getAnnotation(SpringUI.class).path().trim();

        try {

            if(appProps == null){

                String currentDataSourceId = dataSourceConfigurer.dataSourceProperties().getCurrentDataSourceId();

                appProps = new ConfigFileUtil()

                        .setDefaultContent(APP_FILE_CONTENT)

                        .getProperties(currentDataSourceId, PROPERTIES_NAME);

            }

            if(appProps.get(CDM_VAADIN_UI_ACTIVATED) != null){

                String[] uiPaths = appProps.get(CDM_VAADIN_UI_ACTIVATED).toString().split("\\s*,\\s*");

                if(Arrays.asList(uiPaths).stream().anyMatch(p -> p.trim().equals(path))){

                    return true;

                }

            }

            throw new InactiveUIException(path);

        } catch (IOException e) {

            logger.error("Error reading the vaadin ui properties file. File corrupted?. Stopping instance ...");

            throw new RuntimeException(e);

        }

    }

}