/*

  * Copyright 2004-2008 the Seasar Foundation and the Others.

  *

  * Licensed under the Apache License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  *

  *     http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, 

  * either express or implied. See the License for the specific language

  * governing permissions and limitations under the License.

  */

 package org.seasar.uruma.rcp.core;

 import java.net.URL;

 import java.util.ArrayList;

 import java.util.Dictionary;

 import java.util.Hashtable;

 import java.util.List;

 import java.util.Properties;

 import org.eclipse.core.internal.preferences.exchange.IProductPreferencesService;

 import org.eclipse.core.internal.preferences.legacy.ProductPreferencesService;

 import org.eclipse.swt.widgets.Display;

 import org.eclipse.swt.widgets.Shell;

 import org.osgi.framework.Bundle;

 import org.osgi.framework.BundleActivator;

 import org.osgi.framework.BundleContext;

 import org.osgi.framework.Constants;

 import org.osgi.framework.ServiceReference;

 import org.seasar.uruma.core.UrumaConstants;

 import org.seasar.uruma.core.UrumaMessageCodes;

 import org.seasar.uruma.exception.UrumaAppInitException;

 import org.seasar.uruma.exception.UrumaAppNotFoundException;

 import org.seasar.uruma.log.UrumaLogger;

 import org.seasar.uruma.rcp.UrumaService;

 import org.seasar.uruma.rcp.core.UrumaBundleState.BundleState;

 import org.seasar.uruma.rcp.util.BundleInfoUtil;

 import org.seasar.uruma.rcp.util.BundleUtil;

 import org.seasar.uruma.ui.dialogs.UrumaErrorDialog;

 import org.seasar.uruma.util.MessageUtil;

 /**

  * Uruma のための {@link BundleActivator} です。<br />

  * 

  * @author y-komori

  */

 public class CoreActivator implements BundleActivator, UrumaConstants,

         UrumaMessageCodes {

     private static final UrumaLogger logger = UrumaLogger

             .getLogger(CoreActivator.class);

     public void start(final BundleContext context) throws Exception {

         logger.log(URUMA_BUNDLE_START);

         try {

             context.addBundleListener(new UrumaBundleListener());

             List<Bundle> activated = prepareUrumaService(context);

             if (activated.size() == 0) {

                 throw new UrumaAppNotFoundException();

             }

             registerProductPreferenceService(context);

             UrumaBundleState.getInstance().setUrumaBundleState(

                     BundleState.AVAILABLE);

         } catch (Throwable ex) {

             Display display = new Display();

             Shell shell = new Shell(display);

             String msg = MessageUtil.getMessageWithBundleName(

                     URUMA_MESSAGE_BASE, "RCP_START_FAILED");

             UrumaErrorDialog dialog = new UrumaErrorDialog(shell, "Uruma", msg,

                     ex);

             dialog.open();

             shell.dispose();

             display.dispose();

         }

     }

     public void stop(final BundleContext context) throws Exception {

         UrumaBundleState.getInstance().setUrumaBundleState(

                 BundleState.NOT_AVAILABLE);

         logger.log(URUMA_BUNDLE_STOP);

     }

     /**

      * Uruma アプリケーションを検索し、アクティベートします。<br />

      * 

      * @param context

      *            Uruma の {@link BundleContext}

      * @return アクティベートに成功した Uruma アプリケーションバンドルのリスト

      */

     @SuppressWarnings("unchecked")

     protected List<Bundle> prepareUrumaService(final BundleContext context) {

         List<Bundle> successedBundleList = new ArrayList<Bundle>();

         String serviceName = UrumaService.class.getName();

         List<Bundle> appBundles = findUrumaApplications(context);

         if (appBundles.size() == 0) {

             throw new UrumaAppNotFoundException();

         }

         Dictionary props = new Properties();

         props.put(URUMA_SERVICE_PROP_APPS, getBundleSymbolicNames(appBundles));

         UrumaServiceFactory factory = new UrumaServiceFactory();

         context.registerService(serviceName, factory, props);

         // Urumaアプリケーションのバンドルに対応する UrumaService を取得することで、

         // Urumaアプリケーションをアクティベートする

         // @see UrumaServiceFactory

         // @see UrumaServiceImpl#initialize()

         for (Bundle bundle : appBundles) {

             setupLog4jConfig(bundle);

             BundleContext appContext = bundle.getBundleContext();

             if (appContext == null) {

                 logger.log(INVALID_URUMA_APP_BUNDLE, bundle.getSymbolicName(),

                         BundleUtil.getBundleState(bundle));

                 continue;

             }

             ServiceReference ref = appContext

                     .getServiceReference(UrumaService.class.getName());

             UrumaServiceImpl service = (UrumaServiceImpl) appContext

                     .getService(ref);

             if (service != null

                     && UrumaBundleState.getInstance().getAppBundleState() == BundleState.AVAILABLE) {

                 service.registerExtensions();

                 successedBundleList.add(bundle);

             } else {

                 Throwable ex = UrumaBundleState.getInstance()

                         .getUrumaAppInitializingException();

                 throw new UrumaAppInitException(bundle, ex, ex.getMessage());

             }

         }

         return successedBundleList;

     }

     /**

      * インストールされているバンドルから Uruma に依存しているバンドルを探して登録します。

      * 

      * @param context

      *            {@link BundleContext} オブジェクト

      * @return Urumaアプリケーションバンドルのリスト

      */

     protected List<Bundle> findUrumaApplications(final BundleContext context) {

         Bundle[] bundles = context.getBundles();

         List<Bundle> appBundles = new ArrayList<Bundle>();

         for (Bundle bundle : bundles) {

             if (isUrumaApplication(bundle)) {

                 logger.log(URUMA_APPLICATION_FOUND, bundle.getSymbolicName());

                 appBundles.add(bundle);

             }

         }

         return appBundles;

     }

     @SuppressWarnings("unchecked")

     protected boolean isUrumaApplication(final Bundle bundle) {

         logger.log(ANALYZING_BUNDLE, bundle.getSymbolicName());

         String require = BundleInfoUtil.getHeader(bundle,

                 BundleInfoUtil.REQUIRE_BUNDLE);

         if (require != null) {

             if (require.indexOf(URUMA_BUNDLE_SYMBOLIC_NAME) > 0) {

                 return true;

             }

         }

         return false;

     }

     protected String[] getBundleSymbolicNames(final List<Bundle> bundles) {

         String[] names = new String[bundles.size()];

         for (int i = 0; i < bundles.size(); i++) {

             names[i] = bundles.get(i).getSymbolicName();

         }

         return names;

     }

     protected void setupLog4jConfig(final Bundle bundle) {

         URL xmlConfig = bundle.getResource(DEFAULT_LOG_XML);

         if (xmlConfig != null) {

             logger.addXmlConfig(xmlConfig);

         } else {

             URL propConfig = bundle.getResource(DEFAULT_LOG_PROPERTIES);

             if (propConfig != null) {

                 logger.addPropertyConfig(propConfig);

             }

         }

     }

     /**

      * {@link UrumaPreferencesService} を {@link IProductPreferencesService}

      * としてサービス登録します。<br />

      * {@link Constants#SERVICE_RANKING} プロパティを 1 に設定することで、 Eclipse の提供する

      * {@link ProductPreferencesService} クラスよりも高い優先度で使用されるようにしています。

      * 

      * @param context

      *            {@link BundleContext} オブジェクト

      */

     protected void registerProductPreferenceService(final BundleContext context) {

         IProductPreferencesService service = new UrumaPreferencesService();

         Dictionary<String, Integer> prop = new Hashtable<String, Integer>();

         prop.put(Constants.SERVICE_RANKING, 1);

         context.registerService(IProductPreferencesService.class.getName(),

                 service, prop);

     }

 }