/*
    * Copyright (C) 2007-2012 Argeo GmbH
    *
    * 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.argeo.cms.ui.workbench.internal.useradmin.commands;
  
  import javax.transaction.Status;
  import javax.transaction.UserTransaction;
  
  import org.argeo.cms.CmsException;
  import org.argeo.cms.ui.workbench.WorkbenchUiPlugin;
  import org.argeo.cms.ui.workbench.internal.useradmin.UiAdminUtils;
  import org.argeo.cms.ui.workbench.internal.useradmin.UserAdminWrapper;
  import org.eclipse.core.commands.AbstractHandler;
  import org.eclipse.core.commands.ExecutionEvent;
  import org.eclipse.core.commands.ExecutionException;
  import org.osgi.service.useradmin.UserAdminEvent;
  
  /** Manage the transaction that is bound to the current perspective */
  public class UserTransactionHandler extends AbstractHandler {
  	public final static String ID = WorkbenchUiPlugin.PLUGIN_ID
  			+ ".userTransactionHandler";
  
  	public final static String PARAM_COMMAND_ID = "param.commandId";
  
  	public final static String TRANSACTION_BEGIN = "transaction.begin";
  	public final static String TRANSACTION_COMMIT = "transaction.commit";
  	public final static String TRANSACTION_ROLLBACK = "transaction.rollback";
  
  	/* DEPENDENCY INJECTION */
  	private UserAdminWrapper userAdminWrapper;
  
  	public Object execute(ExecutionEvent event) throws ExecutionException {
  		String commandId = event.getParameter(PARAM_COMMAND_ID);
  		final UserTransaction userTransaction = userAdminWrapper
  				.getUserTransaction();
  		try {
  			if (TRANSACTION_BEGIN.equals(commandId)) {
  				if (userTransaction.getStatus() != Status.STATUS_NO_TRANSACTION)
  					throw new CmsException("A transaction already exists");
  				else
  					userTransaction.begin();
  			} else if (TRANSACTION_COMMIT.equals(commandId)) {
  				if (userTransaction.getStatus() == Status.STATUS_NO_TRANSACTION)
  					throw new CmsException("No transaction.");
  				else
  					userTransaction.commit();
  			} else if (TRANSACTION_ROLLBACK.equals(commandId)) {
  				if (userTransaction.getStatus() == Status.STATUS_NO_TRANSACTION)
  					throw new CmsException("No transaction to rollback.");
  				else {
  					userTransaction.rollback();
  					userAdminWrapper.notifyListeners(new UserAdminEvent(null,
  							UserAdminEvent.ROLE_CHANGED, null));
  				}
  			}
  
  			UiAdminUtils.notifyTransactionStateChange(userTransaction);
  			// Try to remove invalid thread access errors when managing users.
  			// HandlerUtil.getActivePart(event).getSite().getShell().getDisplay()
  			// .asyncExec(new Runnable() {
  			// @Override
  			// public void run() {
  			// UiAdminUtils
  			// .notifyTransactionStateChange(userTransaction);
  			// }
  			// });
  
  		} catch (CmsException e) {
  			throw e;
  		} catch (Exception e) {
  			throw new CmsException("Unable to call " + commandId + " on "
  					+ userTransaction, e);
  		}
  		return null;
  	}
  
  	/* DEPENDENCY INJECTION */
  	public void setUserAdminWrapper(UserAdminWrapper userAdminWrapper) {
  		this.userAdminWrapper = userAdminWrapper;
  	}
  }